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	Version: linux-6.0.1 spark-3.0.0 hadoop-3.2.0-src hadoop-3.3.0-src spark-2.4.7 linux-4.15.13 hadoop-2.7.4-src Revert   Change

 // SPDX-License-Identifier: GPL-2.0
 #include <linux/acpi.h>
 #include <linux/ctype.h>
 #include <linux/debugfs.h>
 #include <linux/delay.h>
 #include <linux/gpio/consumer.h>
 #include <linux/hwmon.h>
 #include <linux/i2c.h>
 #include <linux/interrupt.h>
 #include <linux/jiffies.h>
 #include <linux/mdio/mdio-i2c.h>
 #include <linux/module.h>
 #include <linux/mutex.h>
 #include <linux/of.h>
 #include <linux/phy.h>
 #include <linux/platform_device.h>
 #include <linux/rtnetlink.h>
 #include <linux/slab.h>
 #include <linux/workqueue.h>
 
 #include "sfp.h"
 #include "swphy.h"
 
 enum {
     GPIO_MODDEF0,
     GPIO_LOS,
     GPIO_TX_FAULT,
     GPIO_TX_DISABLE,
     GPIO_RATE_SELECT,
     GPIO_MAX,
 
     SFP_F_PRESENT = BIT(GPIO_MODDEF0),
     SFP_F_LOS = BIT(GPIO_LOS),
     SFP_F_TX_FAULT = BIT(GPIO_TX_FAULT),
     SFP_F_TX_DISABLE = BIT(GPIO_TX_DISABLE),
     SFP_F_RATE_SELECT = BIT(GPIO_RATE_SELECT),
 
     SFP_E_INSERT = 0,
     SFP_E_REMOVE,
     SFP_E_DEV_ATTACH,
     SFP_E_DEV_DETACH,
     SFP_E_DEV_DOWN,
     SFP_E_DEV_UP,
     SFP_E_TX_FAULT,
     SFP_E_TX_CLEAR,
     SFP_E_LOS_HIGH,
     SFP_E_LOS_LOW,
     SFP_E_TIMEOUT,
 
     SFP_MOD_EMPTY = 0,
     SFP_MOD_ERROR,
     SFP_MOD_PROBE,
     SFP_MOD_WAITDEV,
     SFP_MOD_HPOWER,
     SFP_MOD_WAITPWR,
     SFP_MOD_PRESENT,
 
     SFP_DEV_DETACHED = 0,
     SFP_DEV_DOWN,
     SFP_DEV_UP,
 
     SFP_S_DOWN = 0,
     SFP_S_FAIL,
     SFP_S_WAIT,
     SFP_S_INIT,
     SFP_S_INIT_PHY,
     SFP_S_INIT_TX_FAULT,
     SFP_S_WAIT_LOS,
     SFP_S_LINK_UP,
     SFP_S_TX_FAULT,
     SFP_S_REINIT,
     SFP_S_TX_DISABLE,
 };
 
 static const char  * const mod_state_strings[] = {
     [SFP_MOD_EMPTY] = "empty",
     [SFP_MOD_ERROR] = "error",
     [SFP_MOD_PROBE] = "probe",
     [SFP_MOD_WAITDEV] = "waitdev",
     [SFP_MOD_HPOWER] = "hpower",
     [SFP_MOD_WAITPWR] = "waitpwr",
     [SFP_MOD_PRESENT] = "present",
 };
 
 static const char *mod_state_to_str(unsigned short mod_state)
 {
     if (mod_state >= ARRAY_SIZE(mod_state_strings))
         return "Unknown module state";
     return mod_state_strings[mod_state];
 }
 
 static const char * const dev_state_strings[] = {
     [SFP_DEV_DETACHED] = "detached",
     [SFP_DEV_DOWN] = "down",
     [SFP_DEV_UP] = "up",
 };
 
 static const char *dev_state_to_str(unsigned short dev_state)
 {
     if (dev_state >= ARRAY_SIZE(dev_state_strings))
         return "Unknown device state";
     return dev_state_strings[dev_state];
 }
 
 static const char * const event_strings[] = {
     [SFP_E_INSERT] = "insert",
     [SFP_E_REMOVE] = "remove",
     [SFP_E_DEV_ATTACH] = "dev_attach",
     [SFP_E_DEV_DETACH] = "dev_detach",
     [SFP_E_DEV_DOWN] = "dev_down",
     [SFP_E_DEV_UP] = "dev_up",
     [SFP_E_TX_FAULT] = "tx_fault",
     [SFP_E_TX_CLEAR] = "tx_clear",
     [SFP_E_LOS_HIGH] = "los_high",
     [SFP_E_LOS_LOW] = "los_low",
     [SFP_E_TIMEOUT] = "timeout",
 };
 
 static const char *event_to_str(unsigned short event)
 {
     if (event >= ARRAY_SIZE(event_strings))
         return "Unknown event";
     return event_strings[event];
 }
 
 static const char * const sm_state_strings[] = {
     [SFP_S_DOWN] = "down",
     [SFP_S_FAIL] = "fail",
     [SFP_S_WAIT] = "wait",
     [SFP_S_INIT] = "init",
     [SFP_S_INIT_PHY] = "init_phy",
     [SFP_S_INIT_TX_FAULT] = "init_tx_fault",
     [SFP_S_WAIT_LOS] = "wait_los",
     [SFP_S_LINK_UP] = "link_up",
     [SFP_S_TX_FAULT] = "tx_fault",
     [SFP_S_REINIT] = "reinit",
     [SFP_S_TX_DISABLE] = "tx_disable",
 };
 
 static const char *sm_state_to_str(unsigned short sm_state)
 {
     if (sm_state >= ARRAY_SIZE(sm_state_strings))
         return "Unknown state";
     return sm_state_strings[sm_state];
 }
 
 static const char *gpio_of_names[] = {
     "mod-def0",
     "los",
     "tx-fault",
     "tx-disable",
     "rate-select0",
 };
 
 static const enum gpiod_flags gpio_flags[] = {
     GPIOD_IN,
     GPIOD_IN,
     GPIOD_IN,
     GPIOD_ASIS,
     GPIOD_ASIS,
 };
 
 /* t_start_up (SFF-8431) or t_init (SFF-8472) is the time required for a
  * non-cooled module to initialise its laser safety circuitry. We wait
  * an initial T_WAIT period before we check the tx fault to give any PHY
  * on board (for a copper SFP) time to initialise.
  */
 #define T_WAIT          msecs_to_jiffies(50)
 #define T_START_UP      msecs_to_jiffies(300)
 #define T_START_UP_BAD_GPON msecs_to_jiffies(60000)
 
 /* t_reset is the time required to assert the TX_DISABLE signal to reset
  * an indicated TX_FAULT.
  */
 #define T_RESET_US      10
 #define T_FAULT_RECOVER     msecs_to_jiffies(1000)
 
 /* N_FAULT_INIT is the number of recovery attempts at module initialisation
  * time. If the TX_FAULT signal is not deasserted after this number of
  * attempts at clearing it, we decide that the module is faulty.
  * N_FAULT is the same but after the module has initialised.
  */
 #define N_FAULT_INIT        5
 #define N_FAULT         5
 
 /* T_PHY_RETRY is the time interval between attempts to probe the PHY.
  * R_PHY_RETRY is the number of attempts.
  */
 #define T_PHY_RETRY     msecs_to_jiffies(50)
 #define R_PHY_RETRY     12
 
 /* SFP module presence detection is poor: the three MOD DEF signals are
  * the same length on the PCB, which means it's possible for MOD DEF 0 to
  * connect before the I2C bus on MOD DEF 1/2.
  *
  * The SFF-8472 specifies t_serial ("Time from power on until module is
  * ready for data transmission over the two wire serial bus.") as 300ms.
  */
 #define T_SERIAL        msecs_to_jiffies(300)
 #define T_HPOWER_LEVEL      msecs_to_jiffies(300)
 #define T_PROBE_RETRY_INIT  msecs_to_jiffies(100)
 #define R_PROBE_RETRY_INIT  10
 #define T_PROBE_RETRY_SLOW  msecs_to_jiffies(5000)
 #define R_PROBE_RETRY_SLOW  12
 
 /* SFP modules appear to always have their PHY configured for bus address
  * 0x56 (which with mdio-i2c, translates to a PHY address of 22).
  */
 #define SFP_PHY_ADDR    22
 
 struct sff_data {
     unsigned int gpios;
     bool (*module_supported)(const struct sfp_eeprom_id *id);
 };
 
 struct sfp {
     struct device *dev;
     struct i2c_adapter *i2c;
     struct mii_bus *i2c_mii;
     struct sfp_bus *sfp_bus;
     struct phy_device *mod_phy;
     const struct sff_data *type;
     size_t i2c_block_size;
     u32 max_power_mW;
 
     unsigned int (*get_state)(struct sfp *);
     void (*set_state)(struct sfp *, unsigned int);
     int (*read)(struct sfp *, bool, u8, void *, size_t);
     int (*write)(struct sfp *, bool, u8, void *, size_t);
 
     struct gpio_desc *gpio[GPIO_MAX];
     int gpio_irq[GPIO_MAX];
 
     bool need_poll;
 
     struct mutex st_mutex;          /* Protects state */
     unsigned int state_soft_mask;
     unsigned int state;
     struct delayed_work poll;
     struct delayed_work timeout;
     struct mutex sm_mutex;          /* Protects state machine */
     unsigned char sm_mod_state;
     unsigned char sm_mod_tries_init;
     unsigned char sm_mod_tries;
     unsigned char sm_dev_state;
     unsigned short sm_state;
     unsigned char sm_fault_retries;
     unsigned char sm_phy_retries;
 
     struct sfp_eeprom_id id;
     unsigned int module_power_mW;
     unsigned int module_t_start_up;
     bool tx_fault_ignore;
 
 #if IS_ENABLED(CONFIG_HWMON)
     struct sfp_diag diag;
     struct delayed_work hwmon_probe;
     unsigned int hwmon_tries;
     struct device *hwmon_dev;
     char *hwmon_name;
 #endif
 
 #if IS_ENABLED(CONFIG_DEBUG_FS)
     struct dentry *debugfs_dir;
 #endif
 };
 
 static bool sff_module_supported(const struct sfp_eeprom_id *id)
 {
     return id->base.phys_id == SFF8024_ID_SFF_8472 &&
            id->base.phys_ext_id == SFP_PHYS_EXT_ID_SFP;
 }
 
 static const struct sff_data sff_data = {
     .gpios = SFP_F_LOS | SFP_F_TX_FAULT | SFP_F_TX_DISABLE,
     .module_supported = sff_module_supported,
 };
 
 static bool sfp_module_supported(const struct sfp_eeprom_id *id)
 {
     if (id->base.phys_id == SFF8024_ID_SFP &&
         id->base.phys_ext_id == SFP_PHYS_EXT_ID_SFP)
         return true;
 
     /* SFP GPON module Ubiquiti U-Fiber Instant has in its EEPROM stored
      * phys id SFF instead of SFP. Therefore mark this module explicitly
      * as supported based on vendor name and pn match.
      */
     if (id->base.phys_id == SFF8024_ID_SFF_8472 &&
         id->base.phys_ext_id == SFP_PHYS_EXT_ID_SFP &&
         !memcmp(id->base.vendor_name, "UBNT            ", 16) &&
         !memcmp(id->base.vendor_pn, "UF-INSTANT      ", 16))
         return true;
 
     return false;
 }
 
 static const struct sff_data sfp_data = {
     .gpios = SFP_F_PRESENT | SFP_F_LOS | SFP_F_TX_FAULT |
          SFP_F_TX_DISABLE | SFP_F_RATE_SELECT,
     .module_supported = sfp_module_supported,
 };
 
 static const struct of_device_id sfp_of_match[] = {
     { .compatible = "sff,sff", .data = &sff_data, },
     { .compatible = "sff,sfp", .data = &sfp_data, },
     { },
 };
 MODULE_DEVICE_TABLE(of, sfp_of_match);
 
 static unsigned long poll_jiffies;
 
 static unsigned int sfp_gpio_get_state(struct sfp *sfp)
 {
     unsigned int i, state, v;
 
     for (i = state = 0; i < GPIO_MAX; i++) {
         if (gpio_flags[i] != GPIOD_IN || !sfp->gpio[i])
             continue;
 
         v = gpiod_get_value_cansleep(sfp->gpio[i]);
         if (v)
             state |= BIT(i);
     }
 
     return state;
 }
 
 static unsigned int sff_gpio_get_state(struct sfp *sfp)
 {
     return sfp_gpio_get_state(sfp) | SFP_F_PRESENT;
 }
 
 static void sfp_gpio_set_state(struct sfp *sfp, unsigned int state)
 {
     if (state & SFP_F_PRESENT) {
         /* If the module is present, drive the signals */
         if (sfp->gpio[GPIO_TX_DISABLE])
             gpiod_direction_output(sfp->gpio[GPIO_TX_DISABLE],
                            state & SFP_F_TX_DISABLE);
         if (state & SFP_F_RATE_SELECT)
             gpiod_direction_output(sfp->gpio[GPIO_RATE_SELECT],
                            state & SFP_F_RATE_SELECT);
     } else {
         /* Otherwise, let them float to the pull-ups */
         if (sfp->gpio[GPIO_TX_DISABLE])
             gpiod_direction_input(sfp->gpio[GPIO_TX_DISABLE]);
         if (state & SFP_F_RATE_SELECT)
             gpiod_direction_input(sfp->gpio[GPIO_RATE_SELECT]);
     }
 }
 
 static int sfp_i2c_read(struct sfp *sfp, bool a2, u8 dev_addr, void *buf,
             size_t len)
 {
     struct i2c_msg msgs[2];
     u8 bus_addr = a2 ? 0x51 : 0x50;
     size_t block_size = sfp->i2c_block_size;
     size_t this_len;
     int ret;
 
     msgs[0].addr = bus_addr;
     msgs[0].flags = 0;
     msgs[0].len = 1;
     msgs[0].buf = &dev_addr;
     msgs[1].addr = bus_addr;
     msgs[1].flags = I2C_M_RD;
     msgs[1].len = len;
     msgs[1].buf = buf;
 
     while (len) {
         this_len = len;
         if (this_len > block_size)
             this_len = block_size;
 
         msgs[1].len = this_len;
 
         ret = i2c_transfer(sfp->i2c, msgs, ARRAY_SIZE(msgs));
         if (ret < 0)
             return ret;
 
         if (ret != ARRAY_SIZE(msgs))
             break;
 
         msgs[1].buf += this_len;
         dev_addr += this_len;
         len -= this_len;
     }
 
     return msgs[1].buf - (u8 *)buf;
 }
 
 static int sfp_i2c_write(struct sfp *sfp, bool a2, u8 dev_addr, void *buf,
     size_t len)
 {
     struct i2c_msg msgs[1];
     u8 bus_addr = a2 ? 0x51 : 0x50;
     int ret;
 
     msgs[0].addr = bus_addr;
     msgs[0].flags = 0;
     msgs[0].len = 1 + len;
     msgs[0].buf = kmalloc(1 + len, GFP_KERNEL);
     if (!msgs[0].buf)
         return -ENOMEM;
 
     msgs[0].buf[0] = dev_addr;
     memcpy(&msgs[0].buf[1], buf, len);
 
     ret = i2c_transfer(sfp->i2c, msgs, ARRAY_SIZE(msgs));
 
     kfree(msgs[0].buf);
 
     if (ret < 0)
         return ret;
 
     return ret == ARRAY_SIZE(msgs) ? len : 0;
 }
 
 static int sfp_i2c_configure(struct sfp *sfp, struct i2c_adapter *i2c)
 {
     struct mii_bus *i2c_mii;
     int ret;
 
     if (!i2c_check_functionality(i2c, I2C_FUNC_I2C))
         return -EINVAL;
 
     sfp->i2c = i2c;
     sfp->read = sfp_i2c_read;
     sfp->write = sfp_i2c_write;
 
     i2c_mii = mdio_i2c_alloc(sfp->dev, i2c);
     if (IS_ERR(i2c_mii))
         return PTR_ERR(i2c_mii);
 
     i2c_mii->name = "SFP I2C Bus";
     i2c_mii->phy_mask = ~0;
 
     ret = mdiobus_register(i2c_mii);
     if (ret < 0) {
         mdiobus_free(i2c_mii);
         return ret;
     }
 
     sfp->i2c_mii = i2c_mii;
 
     return 0;
 }
 
 /* Interface */
 static int sfp_read(struct sfp *sfp, bool a2, u8 addr, void *buf, size_t len)
 {
     return sfp->read(sfp, a2, addr, buf, len);
 }
 
 static int sfp_write(struct sfp *sfp, bool a2, u8 addr, void *buf, size_t len)
 {
     return sfp->write(sfp, a2, addr, buf, len);
 }
 
 static unsigned int sfp_soft_get_state(struct sfp *sfp)
 {
     unsigned int state = 0;
     u8 status;
     int ret;
 
     ret = sfp_read(sfp, true, SFP_STATUS, &status, sizeof(status));
     if (ret == sizeof(status)) {
         if (status & SFP_STATUS_RX_LOS)
             state |= SFP_F_LOS;
         if (status & SFP_STATUS_TX_FAULT)
             state |= SFP_F_TX_FAULT;
     } else {
         dev_err_ratelimited(sfp->dev,
                     "failed to read SFP soft status: %pe\n",
                     ERR_PTR(ret));
         /* Preserve the current state */
         state = sfp->state;
     }
 
     return state & sfp->state_soft_mask;
 }
 
 static void sfp_soft_set_state(struct sfp *sfp, unsigned int state)
 {
     u8 status;
 
     if (sfp_read(sfp, true, SFP_STATUS, &status, sizeof(status)) ==
              sizeof(status)) {
         if (state & SFP_F_TX_DISABLE)
             status |= SFP_STATUS_TX_DISABLE_FORCE;
         else
             status &= ~SFP_STATUS_TX_DISABLE_FORCE;
 
         sfp_write(sfp, true, SFP_STATUS, &status, sizeof(status));
     }
 }
 
 static void sfp_soft_start_poll(struct sfp *sfp)
 {
     const struct sfp_eeprom_id *id = &sfp->id;
 
     sfp->state_soft_mask = 0;
     if (id->ext.enhopts & SFP_ENHOPTS_SOFT_TX_DISABLE &&
         !sfp->gpio[GPIO_TX_DISABLE])
         sfp->state_soft_mask |= SFP_F_TX_DISABLE;
     if (id->ext.enhopts & SFP_ENHOPTS_SOFT_TX_FAULT &&
         !sfp->gpio[GPIO_TX_FAULT])
         sfp->state_soft_mask |= SFP_F_TX_FAULT;
     if (id->ext.enhopts & SFP_ENHOPTS_SOFT_RX_LOS &&
         !sfp->gpio[GPIO_LOS])
         sfp->state_soft_mask |= SFP_F_LOS;
 
     if (sfp->state_soft_mask & (SFP_F_LOS | SFP_F_TX_FAULT) &&
         !sfp->need_poll)
         mod_delayed_work(system_wq, &sfp->poll, poll_jiffies);
 }
 
 static void sfp_soft_stop_poll(struct sfp *sfp)
 {
     sfp->state_soft_mask = 0;
 }
 
 static unsigned int sfp_get_state(struct sfp *sfp)
 {
     unsigned int state = sfp->get_state(sfp);
 
     if (state & SFP_F_PRESENT &&
         sfp->state_soft_mask & (SFP_F_LOS | SFP_F_TX_FAULT))
         state |= sfp_soft_get_state(sfp);
 
     return state;
 }
 
 static void sfp_set_state(struct sfp *sfp, unsigned int state)
 {
     sfp->set_state(sfp, state);
 
     if (state & SFP_F_PRESENT &&
         sfp->state_soft_mask & SFP_F_TX_DISABLE)
         sfp_soft_set_state(sfp, state);
 }
 
 static unsigned int sfp_check(void *buf, size_t len)
 {
     u8 *p, check;
 
     for (p = buf, check = 0; len; p++, len--)
         check += *p;
 
     return check;
 }
 
 /* hwmon */
 #if IS_ENABLED(CONFIG_HWMON)
 static umode_t sfp_hwmon_is_visible(const void *data,
                     enum hwmon_sensor_types type,
                     u32 attr, int channel)
 {
     const struct sfp *sfp = data;
 
     switch (type) {
     case hwmon_temp:
         switch (attr) {
         case hwmon_temp_min_alarm:
         case hwmon_temp_max_alarm:
         case hwmon_temp_lcrit_alarm:
         case hwmon_temp_crit_alarm:
         case hwmon_temp_min:
         case hwmon_temp_max:
         case hwmon_temp_lcrit:
         case hwmon_temp_crit:
             if (!(sfp->id.ext.enhopts & SFP_ENHOPTS_ALARMWARN))
                 return 0;
             fallthrough;
         case hwmon_temp_input:
         case hwmon_temp_label:
             return 0444;
         default:
             return 0;
         }
     case hwmon_in:
         switch (attr) {
         case hwmon_in_min_alarm:
         case hwmon_in_max_alarm:
         case hwmon_in_lcrit_alarm:
         case hwmon_in_crit_alarm:
         case hwmon_in_min:
         case hwmon_in_max:
         case hwmon_in_lcrit:
         case hwmon_in_crit:
             if (!(sfp->id.ext.enhopts & SFP_ENHOPTS_ALARMWARN))
                 return 0;
             fallthrough;
         case hwmon_in_input:
         case hwmon_in_label:
             return 0444;
         default:
             return 0;
         }
     case hwmon_curr:
         switch (attr) {
         case hwmon_curr_min_alarm:
         case hwmon_curr_max_alarm:
         case hwmon_curr_lcrit_alarm:
         case hwmon_curr_crit_alarm:
         case hwmon_curr_min:
         case hwmon_curr_max:
         case hwmon_curr_lcrit:
         case hwmon_curr_crit:
             if (!(sfp->id.ext.enhopts & SFP_ENHOPTS_ALARMWARN))
                 return 0;
             fallthrough;
         case hwmon_curr_input:
         case hwmon_curr_label:
             return 0444;
         default:
             return 0;
         }
     case hwmon_power:
         /* External calibration of receive power requires
          * floating point arithmetic. Doing that in the kernel
          * is not easy, so just skip it. If the module does
          * not require external calibration, we can however
          * show receiver power, since FP is then not needed.
          */
         if (sfp->id.ext.diagmon & SFP_DIAGMON_EXT_CAL &&
             channel == 1)
             return 0;
         switch (attr) {
         case hwmon_power_min_alarm:
         case hwmon_power_max_alarm:
         case hwmon_power_lcrit_alarm:
         case hwmon_power_crit_alarm:
         case hwmon_power_min:
         case hwmon_power_max:
         case hwmon_power_lcrit:
         case hwmon_power_crit:
             if (!(sfp->id.ext.enhopts & SFP_ENHOPTS_ALARMWARN))
                 return 0;
             fallthrough;
         case hwmon_power_input:
         case hwmon_power_label:
             return 0444;
         default:
             return 0;
         }
     default:
         return 0;
     }
 }
 
 static int sfp_hwmon_read_sensor(struct sfp *sfp, int reg, long *value)
 {
     __be16 val;
     int err;
 
     err = sfp_read(sfp, true, reg, &val, sizeof(val));
     if (err < 0)
         return err;
 
     *value = be16_to_cpu(val);
 
     return 0;
 }
 
 static void sfp_hwmon_to_rx_power(long *value)
 {
     *value = DIV_ROUND_CLOSEST(*value, 10);
 }
 
 static void sfp_hwmon_calibrate(struct sfp *sfp, unsigned int slope, int offset,
                 long *value)
 {
     if (sfp->id.ext.diagmon & SFP_DIAGMON_EXT_CAL)
         *value = DIV_ROUND_CLOSEST(*value * slope, 256) + offset;
 }
 
 static void sfp_hwmon_calibrate_temp(struct sfp *sfp, long *value)
 {
     sfp_hwmon_calibrate(sfp, be16_to_cpu(sfp->diag.cal_t_slope),
                 be16_to_cpu(sfp->diag.cal_t_offset), value);
 
     if (*value >= 0x8000)
         *value -= 0x10000;
 
     *value = DIV_ROUND_CLOSEST(*value * 1000, 256);
 }
 
 static void sfp_hwmon_calibrate_vcc(struct sfp *sfp, long *value)
 {
     sfp_hwmon_calibrate(sfp, be16_to_cpu(sfp->diag.cal_v_slope),
                 be16_to_cpu(sfp->diag.cal_v_offset), value);
 
     *value = DIV_ROUND_CLOSEST(*value, 10);
 }
 
 static void sfp_hwmon_calibrate_bias(struct sfp *sfp, long *value)
 {
     sfp_hwmon_calibrate(sfp, be16_to_cpu(sfp->diag.cal_txi_slope),
                 be16_to_cpu(sfp->diag.cal_txi_offset), value);
 
     *value = DIV_ROUND_CLOSEST(*value, 500);
 }
 
 static void sfp_hwmon_calibrate_tx_power(struct sfp *sfp, long *value)
 {
     sfp_hwmon_calibrate(sfp, be16_to_cpu(sfp->diag.cal_txpwr_slope),
                 be16_to_cpu(sfp->diag.cal_txpwr_offset), value);
 
     *value = DIV_ROUND_CLOSEST(*value, 10);
 }
 
 static int sfp_hwmon_read_temp(struct sfp *sfp, int reg, long *value)
 {
     int err;
 
     err = sfp_hwmon_read_sensor(sfp, reg, value);
     if (err < 0)
         return err;
 
     sfp_hwmon_calibrate_temp(sfp, value);
 
     return 0;
 }
 
 static int sfp_hwmon_read_vcc(struct sfp *sfp, int reg, long *value)
 {
     int err;
 
     err = sfp_hwmon_read_sensor(sfp, reg, value);
     if (err < 0)
         return err;
 
     sfp_hwmon_calibrate_vcc(sfp, value);
 
     return 0;
 }
 
 static int sfp_hwmon_read_bias(struct sfp *sfp, int reg, long *value)
 {
     int err;
 
     err = sfp_hwmon_read_sensor(sfp, reg, value);
     if (err < 0)
         return err;
 
     sfp_hwmon_calibrate_bias(sfp, value);
 
     return 0;
 }
 
 static int sfp_hwmon_read_tx_power(struct sfp *sfp, int reg, long *value)
 {
     int err;
 
     err = sfp_hwmon_read_sensor(sfp, reg, value);
     if (err < 0)
         return err;
 
     sfp_hwmon_calibrate_tx_power(sfp, value);
 
     return 0;
 }
 
 static int sfp_hwmon_read_rx_power(struct sfp *sfp, int reg, long *value)
 {
     int err;
 
     err = sfp_hwmon_read_sensor(sfp, reg, value);
     if (err < 0)
         return err;
 
     sfp_hwmon_to_rx_power(value);
 
     return 0;
 }
 
 static int sfp_hwmon_temp(struct sfp *sfp, u32 attr, long *value)
 {
     u8 status;
     int err;
 
     switch (attr) {
     case hwmon_temp_input:
         return sfp_hwmon_read_temp(sfp, SFP_TEMP, value);
 
     case hwmon_temp_lcrit:
         *value = be16_to_cpu(sfp->diag.temp_low_alarm);
         sfp_hwmon_calibrate_temp(sfp, value);
         return 0;
 
     case hwmon_temp_min:
         *value = be16_to_cpu(sfp->diag.temp_low_warn);
         sfp_hwmon_calibrate_temp(sfp, value);
         return 0;
     case hwmon_temp_max:
         *value = be16_to_cpu(sfp->diag.temp_high_warn);
         sfp_hwmon_calibrate_temp(sfp, value);
         return 0;
 
     case hwmon_temp_crit:
         *value = be16_to_cpu(sfp->diag.temp_high_alarm);
         sfp_hwmon_calibrate_temp(sfp, value);
         return 0;
 
     case hwmon_temp_lcrit_alarm:
         err = sfp_read(sfp, true, SFP_ALARM0, &status, sizeof(status));
         if (err < 0)
             return err;
 
         *value = !!(status & SFP_ALARM0_TEMP_LOW);
         return 0;
 
     case hwmon_temp_min_alarm:
         err = sfp_read(sfp, true, SFP_WARN0, &status, sizeof(status));
         if (err < 0)
             return err;
 
         *value = !!(status & SFP_WARN0_TEMP_LOW);
         return 0;
 
     case hwmon_temp_max_alarm:
         err = sfp_read(sfp, true, SFP_WARN0, &status, sizeof(status));
         if (err < 0)
             return err;
 
         *value = !!(status & SFP_WARN0_TEMP_HIGH);
         return 0;
 
     case hwmon_temp_crit_alarm:
         err = sfp_read(sfp, true, SFP_ALARM0, &status, sizeof(status));
         if (err < 0)
             return err;
 
         *value = !!(status & SFP_ALARM0_TEMP_HIGH);
         return 0;
     default:
         return -EOPNOTSUPP;
     }
 
     return -EOPNOTSUPP;
 }
 
 static int sfp_hwmon_vcc(struct sfp *sfp, u32 attr, long *value)
 {
     u8 status;
     int err;
 
     switch (attr) {
     case hwmon_in_input:
         return sfp_hwmon_read_vcc(sfp, SFP_VCC, value);
 
     case hwmon_in_lcrit:
         *value = be16_to_cpu(sfp->diag.volt_low_alarm);
         sfp_hwmon_calibrate_vcc(sfp, value);
         return 0;
 
     case hwmon_in_min:
         *value = be16_to_cpu(sfp->diag.volt_low_warn);
         sfp_hwmon_calibrate_vcc(sfp, value);
         return 0;
 
     case hwmon_in_max:
         *value = be16_to_cpu(sfp->diag.volt_high_warn);
         sfp_hwmon_calibrate_vcc(sfp, value);
         return 0;
 
     case hwmon_in_crit:
         *value = be16_to_cpu(sfp->diag.volt_high_alarm);
         sfp_hwmon_calibrate_vcc(sfp, value);
         return 0;
 
     case hwmon_in_lcrit_alarm:
         err = sfp_read(sfp, true, SFP_ALARM0, &status, sizeof(status));
         if (err < 0)
             return err;
 
         *value = !!(status & SFP_ALARM0_VCC_LOW);
         return 0;
 
     case hwmon_in_min_alarm:
         err = sfp_read(sfp, true, SFP_WARN0, &status, sizeof(status));
         if (err < 0)
             return err;
 
         *value = !!(status & SFP_WARN0_VCC_LOW);
         return 0;
 
     case hwmon_in_max_alarm:
         err = sfp_read(sfp, true, SFP_WARN0, &status, sizeof(status));
         if (err < 0)
             return err;
 
         *value = !!(status & SFP_WARN0_VCC_HIGH);
         return 0;
 
     case hwmon_in_crit_alarm:
         err = sfp_read(sfp, true, SFP_ALARM0, &status, sizeof(status));
         if (err < 0)
             return err;
 
         *value = !!(status & SFP_ALARM0_VCC_HIGH);
         return 0;
     default:
         return -EOPNOTSUPP;
     }
 
     return -EOPNOTSUPP;
 }
 
 static int sfp_hwmon_bias(struct sfp *sfp, u32 attr, long *value)
 {
     u8 status;
     int err;
 
     switch (attr) {
     case hwmon_curr_input:
         return sfp_hwmon_read_bias(sfp, SFP_TX_BIAS, value);
 
     case hwmon_curr_lcrit:
         *value = be16_to_cpu(sfp->diag.bias_low_alarm);
         sfp_hwmon_calibrate_bias(sfp, value);
         return 0;
 
     case hwmon_curr_min:
         *value = be16_to_cpu(sfp->diag.bias_low_warn);
         sfp_hwmon_calibrate_bias(sfp, value);
         return 0;
 
     case hwmon_curr_max:
         *value = be16_to_cpu(sfp->diag.bias_high_warn);
         sfp_hwmon_calibrate_bias(sfp, value);
         return 0;
 
     case hwmon_curr_crit:
         *value = be16_to_cpu(sfp->diag.bias_high_alarm);
         sfp_hwmon_calibrate_bias(sfp, value);
         return 0;
 
     case hwmon_curr_lcrit_alarm:
         err = sfp_read(sfp, true, SFP_ALARM0, &status, sizeof(status));
         if (err < 0)
             return err;
 
         *value = !!(status & SFP_ALARM0_TX_BIAS_LOW);
         return 0;
 
     case hwmon_curr_min_alarm:
         err = sfp_read(sfp, true, SFP_WARN0, &status, sizeof(status));
         if (err < 0)
             return err;
 
         *value = !!(status & SFP_WARN0_TX_BIAS_LOW);
         return 0;
 
     case hwmon_curr_max_alarm:
         err = sfp_read(sfp, true, SFP_WARN0, &status, sizeof(status));
         if (err < 0)
             return err;
 
         *value = !!(status & SFP_WARN0_TX_BIAS_HIGH);
         return 0;
 
     case hwmon_curr_crit_alarm:
         err = sfp_read(sfp, true, SFP_ALARM0, &status, sizeof(status));
         if (err < 0)
             return err;
 
         *value = !!(status & SFP_ALARM0_TX_BIAS_HIGH);
         return 0;
     default:
         return -EOPNOTSUPP;
     }
 
     return -EOPNOTSUPP;
 }
 
 static int sfp_hwmon_tx_power(struct sfp *sfp, u32 attr, long *value)
 {
     u8 status;
     int err;
 
     switch (attr) {
     case hwmon_power_input:
         return sfp_hwmon_read_tx_power(sfp, SFP_TX_POWER, value);
 
     case hwmon_power_lcrit:
         *value = be16_to_cpu(sfp->diag.txpwr_low_alarm);
         sfp_hwmon_calibrate_tx_power(sfp, value);
         return 0;
 
     case hwmon_power_min:
         *value = be16_to_cpu(sfp->diag.txpwr_low_warn);
         sfp_hwmon_calibrate_tx_power(sfp, value);
         return 0;
 
     case hwmon_power_max:
         *value = be16_to_cpu(sfp->diag.txpwr_high_warn);
         sfp_hwmon_calibrate_tx_power(sfp, value);
         return 0;
 
     case hwmon_power_crit:
         *value = be16_to_cpu(sfp->diag.txpwr_high_alarm);
         sfp_hwmon_calibrate_tx_power(sfp, value);
         return 0;
 
     case hwmon_power_lcrit_alarm:
         err = sfp_read(sfp, true, SFP_ALARM0, &status, sizeof(status));
         if (err < 0)
             return err;
 
         *value = !!(status & SFP_ALARM0_TXPWR_LOW);
         return 0;
 
     case hwmon_power_min_alarm:
         err = sfp_read(sfp, true, SFP_WARN0, &status, sizeof(status));
         if (err < 0)
             return err;
 
         *value = !!(status & SFP_WARN0_TXPWR_LOW);
         return 0;
 
     case hwmon_power_max_alarm:
         err = sfp_read(sfp, true, SFP_WARN0, &status, sizeof(status));
         if (err < 0)
             return err;
 
         *value = !!(status & SFP_WARN0_TXPWR_HIGH);
         return 0;
 
     case hwmon_power_crit_alarm:
         err = sfp_read(sfp, true, SFP_ALARM0, &status, sizeof(status));
         if (err < 0)
             return err;
 
         *value = !!(status & SFP_ALARM0_TXPWR_HIGH);
         return 0;
     default:
         return -EOPNOTSUPP;
     }
 
     return -EOPNOTSUPP;
 }
 
 static int sfp_hwmon_rx_power(struct sfp *sfp, u32 attr, long *value)
 {
     u8 status;
     int err;
 
     switch (attr) {
     case hwmon_power_input:
         return sfp_hwmon_read_rx_power(sfp, SFP_RX_POWER, value);
 
     case hwmon_power_lcrit:
         *value = be16_to_cpu(sfp->diag.rxpwr_low_alarm);
         sfp_hwmon_to_rx_power(value);
         return 0;
 
     case hwmon_power_min:
         *value = be16_to_cpu(sfp->diag.rxpwr_low_warn);
         sfp_hwmon_to_rx_power(value);
         return 0;
 
     case hwmon_power_max:
         *value = be16_to_cpu(sfp->diag.rxpwr_high_warn);
         sfp_hwmon_to_rx_power(value);
         return 0;
 
     case hwmon_power_crit:
         *value = be16_to_cpu(sfp->diag.rxpwr_high_alarm);
         sfp_hwmon_to_rx_power(value);
         return 0;
 
     case hwmon_power_lcrit_alarm:
         err = sfp_read(sfp, true, SFP_ALARM1, &status, sizeof(status));
         if (err < 0)
             return err;
 
         *value = !!(status & SFP_ALARM1_RXPWR_LOW);
         return 0;
 
     case hwmon_power_min_alarm:
         err = sfp_read(sfp, true, SFP_WARN1, &status, sizeof(status));
         if (err < 0)
             return err;
 
         *value = !!(status & SFP_WARN1_RXPWR_LOW);
         return 0;
 
     case hwmon_power_max_alarm:
         err = sfp_read(sfp, true, SFP_WARN1, &status, sizeof(status));
         if (err < 0)
             return err;
 
         *value = !!(status & SFP_WARN1_RXPWR_HIGH);
         return 0;
 
     case hwmon_power_crit_alarm:
         err = sfp_read(sfp, true, SFP_ALARM1, &status, sizeof(status));
         if (err < 0)
             return err;
 
         *value = !!(status & SFP_ALARM1_RXPWR_HIGH);
         return 0;
     default:
         return -EOPNOTSUPP;
     }
 
     return -EOPNOTSUPP;
 }
 
 static int sfp_hwmon_read(struct device *dev, enum hwmon_sensor_types type,
               u32 attr, int channel, long *value)
 {
     struct sfp *sfp = dev_get_drvdata(dev);
 
     switch (type) {
     case hwmon_temp:
         return sfp_hwmon_temp(sfp, attr, value);
     case hwmon_in:
         return sfp_hwmon_vcc(sfp, attr, value);
     case hwmon_curr:
         return sfp_hwmon_bias(sfp, attr, value);
     case hwmon_power:
         switch (channel) {
         case 0:
             return sfp_hwmon_tx_power(sfp, attr, value);
         case 1:
             return sfp_hwmon_rx_power(sfp, attr, value);
         default:
             return -EOPNOTSUPP;
         }
     default:
         return -EOPNOTSUPP;
     }
 }
 
 static const char *const sfp_hwmon_power_labels[] = {
     "TX_power",
     "RX_power",
 };
 
 static int sfp_hwmon_read_string(struct device *dev,
                  enum hwmon_sensor_types type,
                  u32 attr, int channel, const char **str)
 {
     switch (type) {
     case hwmon_curr:
         switch (attr) {
         case hwmon_curr_label:
             *str = "bias";
             return 0;
         default:
             return -EOPNOTSUPP;
         }
         break;
     case hwmon_temp:
         switch (attr) {
         case hwmon_temp_label:
             *str = "temperature";
             return 0;
         default:
             return -EOPNOTSUPP;
         }
         break;
     case hwmon_in:
         switch (attr) {
         case hwmon_in_label:
             *str = "VCC";
             return 0;
         default:
             return -EOPNOTSUPP;
         }
         break;
     case hwmon_power:
         switch (attr) {
         case hwmon_power_label:
             *str = sfp_hwmon_power_labels[channel];
             return 0;
         default:
             return -EOPNOTSUPP;
         }
         break;
     default:
         return -EOPNOTSUPP;
     }
 
     return -EOPNOTSUPP;
 }
 
 static const struct hwmon_ops sfp_hwmon_ops = {
     .is_visible = sfp_hwmon_is_visible,
     .read = sfp_hwmon_read,
     .read_string = sfp_hwmon_read_string,
 };
 
 static u32 sfp_hwmon_chip_config[] = {
     HWMON_C_REGISTER_TZ,
     0,
 };
 
 static const struct hwmon_channel_info sfp_hwmon_chip = {
     .type = hwmon_chip,
     .config = sfp_hwmon_chip_config,
 };
 
 static u32 sfp_hwmon_temp_config[] = {
     HWMON_T_INPUT |
     HWMON_T_MAX | HWMON_T_MIN |
     HWMON_T_MAX_ALARM | HWMON_T_MIN_ALARM |
     HWMON_T_CRIT | HWMON_T_LCRIT |
     HWMON_T_CRIT_ALARM | HWMON_T_LCRIT_ALARM |
     HWMON_T_LABEL,
     0,
 };
 
 static const struct hwmon_channel_info sfp_hwmon_temp_channel_info = {
     .type = hwmon_temp,
     .config = sfp_hwmon_temp_config,
 };
 
 static u32 sfp_hwmon_vcc_config[] = {
     HWMON_I_INPUT |
     HWMON_I_MAX | HWMON_I_MIN |
     HWMON_I_MAX_ALARM | HWMON_I_MIN_ALARM |
     HWMON_I_CRIT | HWMON_I_LCRIT |
     HWMON_I_CRIT_ALARM | HWMON_I_LCRIT_ALARM |
     HWMON_I_LABEL,
     0,
 };
 
 static const struct hwmon_channel_info sfp_hwmon_vcc_channel_info = {
     .type = hwmon_in,
     .config = sfp_hwmon_vcc_config,
 };
 
 static u32 sfp_hwmon_bias_config[] = {
     HWMON_C_INPUT |
     HWMON_C_MAX | HWMON_C_MIN |
     HWMON_C_MAX_ALARM | HWMON_C_MIN_ALARM |
     HWMON_C_CRIT | HWMON_C_LCRIT |
     HWMON_C_CRIT_ALARM | HWMON_C_LCRIT_ALARM |
     HWMON_C_LABEL,
     0,
 };
 
 static const struct hwmon_channel_info sfp_hwmon_bias_channel_info = {
     .type = hwmon_curr,
     .config = sfp_hwmon_bias_config,
 };
 
 static u32 sfp_hwmon_power_config[] = {
     /* Transmit power */
     HWMON_P_INPUT |
     HWMON_P_MAX | HWMON_P_MIN |
     HWMON_P_MAX_ALARM | HWMON_P_MIN_ALARM |
     HWMON_P_CRIT | HWMON_P_LCRIT |
     HWMON_P_CRIT_ALARM | HWMON_P_LCRIT_ALARM |
     HWMON_P_LABEL,
     /* Receive power */
     HWMON_P_INPUT |
     HWMON_P_MAX | HWMON_P_MIN |
     HWMON_P_MAX_ALARM | HWMON_P_MIN_ALARM |
     HWMON_P_CRIT | HWMON_P_LCRIT |
     HWMON_P_CRIT_ALARM | HWMON_P_LCRIT_ALARM |
     HWMON_P_LABEL,
     0,
 };
 
 static const struct hwmon_channel_info sfp_hwmon_power_channel_info = {
     .type = hwmon_power,
     .config = sfp_hwmon_power_config,
 };
 
 static const struct hwmon_channel_info *sfp_hwmon_info[] = {
     &sfp_hwmon_chip,
     &sfp_hwmon_vcc_channel_info,
     &sfp_hwmon_temp_channel_info,
     &sfp_hwmon_bias_channel_info,
     &sfp_hwmon_power_channel_info,
     NULL,
 };
 
 static const struct hwmon_chip_info sfp_hwmon_chip_info = {
     .ops = &sfp_hwmon_ops,
     .info = sfp_hwmon_info,
 };
 
 static void sfp_hwmon_probe(struct work_struct *work)
 {
     struct sfp *sfp = container_of(work, struct sfp, hwmon_probe.work);
     int err;
 
     /* hwmon interface needs to access 16bit registers in atomic way to
      * guarantee coherency of the diagnostic monitoring data. If it is not
      * possible to guarantee coherency because EEPROM is broken in such way
      * that does not support atomic 16bit read operation then we have to
      * skip registration of hwmon device.
      */
     if (sfp->i2c_block_size < 2) {
         dev_info(sfp->dev,
              "skipping hwmon device registration due to broken EEPROM\n");
         dev_info(sfp->dev,
              "diagnostic EEPROM area cannot be read atomically to guarantee data coherency\n");
         return;
     }
 
     err = sfp_read(sfp, true, 0, &sfp->diag, sizeof(sfp->diag));
     if (err < 0) {
         if (sfp->hwmon_tries--) {
             mod_delayed_work(system_wq, &sfp->hwmon_probe,
                      T_PROBE_RETRY_SLOW);
         } else {
             dev_warn(sfp->dev, "hwmon probe failed: %pe\n",
                  ERR_PTR(err));
         }
         return;
     }
 
     sfp->hwmon_name = hwmon_sanitize_name(dev_name(sfp->dev));
     if (IS_ERR(sfp->hwmon_name)) {
         dev_err(sfp->dev, "out of memory for hwmon name\n");
         return;
     }
 
     sfp->hwmon_dev = hwmon_device_register_with_info(sfp->dev,
                              sfp->hwmon_name, sfp,
                              &sfp_hwmon_chip_info,
                              NULL);
     if (IS_ERR(sfp->hwmon_dev))
         dev_err(sfp->dev, "failed to register hwmon device: %ld\n",
             PTR_ERR(sfp->hwmon_dev));
 }
 
 static int sfp_hwmon_insert(struct sfp *sfp)
 {
     if (sfp->id.ext.sff8472_compliance == SFP_SFF8472_COMPLIANCE_NONE)
         return 0;
 
     if (!(sfp->id.ext.diagmon & SFP_DIAGMON_DDM))
         return 0;
 
     if (sfp->id.ext.diagmon & SFP_DIAGMON_ADDRMODE)
         /* This driver in general does not support address
          * change.
          */
         return 0;
 
     mod_delayed_work(system_wq, &sfp->hwmon_probe, 1);
     sfp->hwmon_tries = R_PROBE_RETRY_SLOW;
 
     return 0;
 }
 
 static void sfp_hwmon_remove(struct sfp *sfp)
 {
     cancel_delayed_work_sync(&sfp->hwmon_probe);
     if (!IS_ERR_OR_NULL(sfp->hwmon_dev)) {
         hwmon_device_unregister(sfp->hwmon_dev);
         sfp->hwmon_dev = NULL;
         kfree(sfp->hwmon_name);
     }
 }
 
 static int sfp_hwmon_init(struct sfp *sfp)
 {
     INIT_DELAYED_WORK(&sfp->hwmon_probe, sfp_hwmon_probe);
 
     return 0;
 }
 
 static void sfp_hwmon_exit(struct sfp *sfp)
 {
     cancel_delayed_work_sync(&sfp->hwmon_probe);
 }
 #else
 static int sfp_hwmon_insert(struct sfp *sfp)
 {
     return 0;
 }
 
 static void sfp_hwmon_remove(struct sfp *sfp)
 {
 }
 
 static int sfp_hwmon_init(struct sfp *sfp)
 {
     return 0;
 }
 
 static void sfp_hwmon_exit(struct sfp *sfp)
 {
 }
 #endif
 
 /* Helpers */
 static void sfp_module_tx_disable(struct sfp *sfp)
 {
     dev_dbg(sfp->dev, "tx disable %u -> %u\n",
         sfp->state & SFP_F_TX_DISABLE ? 1 : 0, 1);
     sfp->state |= SFP_F_TX_DISABLE;
     sfp_set_state(sfp, sfp->state);
 }
 
 static void sfp_module_tx_enable(struct sfp *sfp)
 {
     dev_dbg(sfp->dev, "tx disable %u -> %u\n",
         sfp->state & SFP_F_TX_DISABLE ? 1 : 0, 0);
     sfp->state &= ~SFP_F_TX_DISABLE;
     sfp_set_state(sfp, sfp->state);
 }
 
 #if IS_ENABLED(CONFIG_DEBUG_FS)
 static int sfp_debug_state_show(struct seq_file *s, void *data)
 {
     struct sfp *sfp = s->private;
 
     seq_printf(s, "Module state: %s\n",
            mod_state_to_str(sfp->sm_mod_state));
     seq_printf(s, "Module probe attempts: %d %d\n",
            R_PROBE_RETRY_INIT - sfp->sm_mod_tries_init,
            R_PROBE_RETRY_SLOW - sfp->sm_mod_tries);
     seq_printf(s, "Device state: %s\n",
            dev_state_to_str(sfp->sm_dev_state));
     seq_printf(s, "Main state: %s\n",
            sm_state_to_str(sfp->sm_state));
     seq_printf(s, "Fault recovery remaining retries: %d\n",
            sfp->sm_fault_retries);
     seq_printf(s, "PHY probe remaining retries: %d\n",
            sfp->sm_phy_retries);
     seq_printf(s, "moddef0: %d\n", !!(sfp->state & SFP_F_PRESENT));
     seq_printf(s, "rx_los: %d\n", !!(sfp->state & SFP_F_LOS));
     seq_printf(s, "tx_fault: %d\n", !!(sfp->state & SFP_F_TX_FAULT));
     seq_printf(s, "tx_disable: %d\n", !!(sfp->state & SFP_F_TX_DISABLE));
     return 0;
 }
 DEFINE_SHOW_ATTRIBUTE(sfp_debug_state);
 
 static void sfp_debugfs_init(struct sfp *sfp)
 {
     sfp->debugfs_dir = debugfs_create_dir(dev_name(sfp->dev), NULL);
 
     debugfs_create_file("state", 0600, sfp->debugfs_dir, sfp,
                 &sfp_debug_state_fops);
 }
 
 static void sfp_debugfs_exit(struct sfp *sfp)
 {
     debugfs_remove_recursive(sfp->debugfs_dir);
 }
 #else
 static void sfp_debugfs_init(struct sfp *sfp)
 {
 }
 
 static void sfp_debugfs_exit(struct sfp *sfp)
 {
 }
 #endif
 
 static void sfp_module_tx_fault_reset(struct sfp *sfp)
 {
     unsigned int state = sfp->state;
 
     if (state & SFP_F_TX_DISABLE)
         return;
 
     sfp_set_state(sfp, state | SFP_F_TX_DISABLE);
 
     udelay(T_RESET_US);
 
     sfp_set_state(sfp, state);
 }
 
 /* SFP state machine */
 static void sfp_sm_set_timer(struct sfp *sfp, unsigned int timeout)
 {
     if (timeout)
         mod_delayed_work(system_power_efficient_wq, &sfp->timeout,
                  timeout);
     else
         cancel_delayed_work(&sfp->timeout);
 }
 
 static void sfp_sm_next(struct sfp *sfp, unsigned int state,
             unsigned int timeout)
 {
     sfp->sm_state = state;
     sfp_sm_set_timer(sfp, timeout);
 }
 
 static void sfp_sm_mod_next(struct sfp *sfp, unsigned int state,
                 unsigned int timeout)
 {
     sfp->sm_mod_state = state;
     sfp_sm_set_timer(sfp, timeout);
 }
 
 static void sfp_sm_phy_detach(struct sfp *sfp)
 {
     sfp_remove_phy(sfp->sfp_bus);
     phy_device_remove(sfp->mod_phy);
     phy_device_free(sfp->mod_phy);
     sfp->mod_phy = NULL;
 }
 
 static int sfp_sm_probe_phy(struct sfp *sfp, bool is_c45)
 {
     struct phy_device *phy;
     int err;
 
     phy = get_phy_device(sfp->i2c_mii, SFP_PHY_ADDR, is_c45);
     if (phy == ERR_PTR(-ENODEV))
         return PTR_ERR(phy);
     if (IS_ERR(phy)) {
         dev_err(sfp->dev, "mdiobus scan returned %pe\n", phy);
         return PTR_ERR(phy);
     }
 
     err = phy_device_register(phy);
     if (err) {
         phy_device_free(phy);
         dev_err(sfp->dev, "phy_device_register failed: %pe\n",
             ERR_PTR(err));
         return err;
     }
 
     err = sfp_add_phy(sfp->sfp_bus, phy);
     if (err) {
         phy_device_remove(phy);
         phy_device_free(phy);
         dev_err(sfp->dev, "sfp_add_phy failed: %pe\n", ERR_PTR(err));
         return err;
     }
 
     sfp->mod_phy = phy;
 
     return 0;
 }
 
 static void sfp_sm_link_up(struct sfp *sfp)
 {
     sfp_link_up(sfp->sfp_bus);
     sfp_sm_next(sfp, SFP_S_LINK_UP, 0);
 }
 
 static void sfp_sm_link_down(struct sfp *sfp)
 {
     sfp_link_down(sfp->sfp_bus);
 }
 
 static void sfp_sm_link_check_los(struct sfp *sfp)
 {
     const __be16 los_inverted = cpu_to_be16(SFP_OPTIONS_LOS_INVERTED);
     const __be16 los_normal = cpu_to_be16(SFP_OPTIONS_LOS_NORMAL);
     __be16 los_options = sfp->id.ext.options & (los_inverted | los_normal);
     bool los = false;
 
     /* If neither SFP_OPTIONS_LOS_INVERTED nor SFP_OPTIONS_LOS_NORMAL
      * are set, we assume that no LOS signal is available. If both are
      * set, we assume LOS is not implemented (and is meaningless.)
      */
     if (los_options == los_inverted)
         los = !(sfp->state & SFP_F_LOS);
     else if (los_options == los_normal)
         los = !!(sfp->state & SFP_F_LOS);
 
     if (los)
         sfp_sm_next(sfp, SFP_S_WAIT_LOS, 0);
     else
         sfp_sm_link_up(sfp);
 }
 
 static bool sfp_los_event_active(struct sfp *sfp, unsigned int event)
 {
     const __be16 los_inverted = cpu_to_be16(SFP_OPTIONS_LOS_INVERTED);
     const __be16 los_normal = cpu_to_be16(SFP_OPTIONS_LOS_NORMAL);
     __be16 los_options = sfp->id.ext.options & (los_inverted | los_normal);
 
     return (los_options == los_inverted && event == SFP_E_LOS_LOW) ||
            (los_options == los_normal && event == SFP_E_LOS_HIGH);
 }
 
 static bool sfp_los_event_inactive(struct sfp *sfp, unsigned int event)
 {
     const __be16 los_inverted = cpu_to_be16(SFP_OPTIONS_LOS_INVERTED);
     const __be16 los_normal = cpu_to_be16(SFP_OPTIONS_LOS_NORMAL);
     __be16 los_options = sfp->id.ext.options & (los_inverted | los_normal);
 
     return (los_options == los_inverted && event == SFP_E_LOS_HIGH) ||
            (los_options == los_normal && event == SFP_E_LOS_LOW);
 }
 
 static void sfp_sm_fault(struct sfp *sfp, unsigned int next_state, bool warn)
 {
     if (sfp->sm_fault_retries && !--sfp->sm_fault_retries) {
         dev_err(sfp->dev,
             "module persistently indicates fault, disabling\n");
         sfp_sm_next(sfp, SFP_S_TX_DISABLE, 0);
     } else {
         if (warn)
             dev_err(sfp->dev, "module transmit fault indicated\n");
 
         sfp_sm_next(sfp, next_state, T_FAULT_RECOVER);
     }
 }
 
 /* Probe a SFP for a PHY device if the module supports copper - the PHY
  * normally sits at I2C bus address 0x56, and may either be a clause 22
  * or clause 45 PHY.
  *
  * Clause 22 copper SFP modules normally operate in Cisco SGMII mode with
  * negotiation enabled, but some may be in 1000base-X - which is for the
  * PHY driver to determine.
  *
  * Clause 45 copper SFP+ modules (10G) appear to switch their interface
  * mode according to the negotiated line speed.
  */
 static int sfp_sm_probe_for_phy(struct sfp *sfp)
 {
     int err = 0;
 
     switch (sfp->id.base.extended_cc) {
     case SFF8024_ECC_10GBASE_T_SFI:
     case SFF8024_ECC_10GBASE_T_SR:
     case SFF8024_ECC_5GBASE_T:
     case SFF8024_ECC_2_5GBASE_T:
         err = sfp_sm_probe_phy(sfp, true);
         break;
 
     default:
         if (sfp->id.base.e1000_base_t)
             err = sfp_sm_probe_phy(sfp, false);
         break;
     }
     return err;
 }
 
 static int sfp_module_parse_power(struct sfp *sfp)
 {
     u32 power_mW = 1000;
     bool supports_a2;
 
     if (sfp->id.ext.options & cpu_to_be16(SFP_OPTIONS_POWER_DECL))
         power_mW = 1500;
     if (sfp->id.ext.options & cpu_to_be16(SFP_OPTIONS_HIGH_POWER_LEVEL))
         power_mW = 2000;
 
     supports_a2 = sfp->id.ext.sff8472_compliance !=
                 SFP_SFF8472_COMPLIANCE_NONE ||
               sfp->id.ext.diagmon & SFP_DIAGMON_DDM;
 
     if (power_mW > sfp->max_power_mW) {
         /* Module power specification exceeds the allowed maximum. */
         if (!supports_a2) {
             /* The module appears not to implement bus address
              * 0xa2, so assume that the module powers up in the
              * indicated mode.
              */
             dev_err(sfp->dev,
                 "Host does not support %u.%uW modules\n",
                 power_mW / 1000, (power_mW / 100) % 10);
             return -EINVAL;
         } else {
             dev_warn(sfp->dev,
                  "Host does not support %u.%uW modules, module left in power mode 1\n",
                  power_mW / 1000, (power_mW / 100) % 10);
             return 0;
         }
     }
 
     if (power_mW <= 1000) {
         /* Modules below 1W do not require a power change sequence */
         sfp->module_power_mW = power_mW;
         return 0;
     }
 
     if (!supports_a2) {
         /* The module power level is below the host maximum and the
          * module appears not to implement bus address 0xa2, so assume
          * that the module powers up in the indicated mode.
          */
         return 0;
     }
 
     /* If the module requires a higher power mode, but also requires
      * an address change sequence, warn the user that the module may
      * not be functional.
      */
     if (sfp->id.ext.diagmon & SFP_DIAGMON_ADDRMODE) {
         dev_warn(sfp->dev,
              "Address Change Sequence not supported but module requires %u.%uW, module may not be functional\n",
              power_mW / 1000, (power_mW / 100) % 10);
         return 0;
     }
 
     sfp->module_power_mW = power_mW;
 
     return 0;
 }
 
 static int sfp_sm_mod_hpower(struct sfp *sfp, bool enable)
 {
     u8 val;
     int err;
 
     err = sfp_read(sfp, true, SFP_EXT_STATUS, &val, sizeof(val));
     if (err != sizeof(val)) {
         dev_err(sfp->dev, "Failed to read EEPROM: %pe\n", ERR_PTR(err));
         return -EAGAIN;
     }
 
     /* DM7052 reports as a high power module, responds to reads (with
      * all bytes 0xff) at 0x51 but does not accept writes.  In any case,
      * if the bit is already set, we're already in high power mode.
      */
     if (!!(val & BIT(0)) == enable)
         return 0;
 
     if (enable)
         val |= BIT(0);
     else
         val &= ~BIT(0);
 
     err = sfp_write(sfp, true, SFP_EXT_STATUS, &val, sizeof(val));
     if (err != sizeof(val)) {
         dev_err(sfp->dev, "Failed to write EEPROM: %pe\n",
             ERR_PTR(err));
         return -EAGAIN;
     }
 
     if (enable)
         dev_info(sfp->dev, "Module switched to %u.%uW power level\n",
              sfp->module_power_mW / 1000,
              (sfp->module_power_mW / 100) % 10);
 
     return 0;
 }
 
 /* GPON modules based on Realtek RTL8672 and RTL9601C chips (e.g. V-SOL
  * V2801F, CarlitoxxPro CPGOS03-0490, Ubiquiti U-Fiber Instant, ...) do
  * not support multibyte reads from the EEPROM. Each multi-byte read
  * operation returns just one byte of EEPROM followed by zeros. There is
  * no way to identify which modules are using Realtek RTL8672 and RTL9601C
  * chips. Moreover every OEM of V-SOL V2801F module puts its own vendor
  * name and vendor id into EEPROM, so there is even no way to detect if
  * module is V-SOL V2801F. Therefore check for those zeros in the read
  * data and then based on check switch to reading EEPROM to one byte
  * at a time.
  */
 static bool sfp_id_needs_byte_io(struct sfp *sfp, void *buf, size_t len)
 {
     size_t i, block_size = sfp->i2c_block_size;
 
     /* Already using byte IO */
     if (block_size == 1)
         return false;
 
     for (i = 1; i < len; i += block_size) {
         if (memchr_inv(buf + i, '\0', min(block_size - 1, len - i)))
             return false;
     }
     return true;
 }
 
 static int sfp_cotsworks_fixup_check(struct sfp *sfp, struct sfp_eeprom_id *id)
 {
     u8 check;
     int err;
 
     if (id->base.phys_id != SFF8024_ID_SFF_8472 ||
         id->base.phys_ext_id != SFP_PHYS_EXT_ID_SFP ||
         id->base.connector != SFF8024_CONNECTOR_LC) {
         dev_warn(sfp->dev, "Rewriting fiber module EEPROM with corrected values\n");
         id->base.phys_id = SFF8024_ID_SFF_8472;
         id->base.phys_ext_id = SFP_PHYS_EXT_ID_SFP;
         id->base.connector = SFF8024_CONNECTOR_LC;
         err = sfp_write(sfp, false, SFP_PHYS_ID, &id->base, 3);
         if (err != 3) {
             dev_err(sfp->dev,
                 "Failed to rewrite module EEPROM: %pe\n",
                 ERR_PTR(err));
             return err;
         }
 
         /* Cotsworks modules have been found to require a delay between write operations. */
         mdelay(50);
 
         /* Update base structure checksum */
         check = sfp_check(&id->base, sizeof(id->base) - 1);
         err = sfp_write(sfp, false, SFP_CC_BASE, &check, 1);
         if (err != 1) {
             dev_err(sfp->dev,
                 "Failed to update base structure checksum in fiber module EEPROM: %pe\n",
                 ERR_PTR(err));
             return err;
         }
     }
     return 0;
 }
 
 static int sfp_sm_mod_probe(struct sfp *sfp, bool report)
 {
     /* SFP module inserted - read I2C data */
     struct sfp_eeprom_id id;
     bool cotsworks_sfbg;
     bool cotsworks;
     u8 check;
     int ret;
 
     /* Some SFP modules and also some Linux I2C drivers do not like reads
      * longer than 16 bytes, so read the EEPROM in chunks of 16 bytes at
      * a time.
      */
     sfp->i2c_block_size = 16;
 
     ret = sfp_read(sfp, false, 0, &id.base, sizeof(id.base));
     if (ret < 0) {
         if (report)
             dev_err(sfp->dev, "failed to read EEPROM: %pe\n",
                 ERR_PTR(ret));
         return -EAGAIN;
     }
 
     if (ret != sizeof(id.base)) {
         dev_err(sfp->dev, "EEPROM short read: %pe\n", ERR_PTR(ret));
         return -EAGAIN;
     }
 
     /* Some SFP modules (e.g. Nokia 3FE46541AA) lock up if read from
      * address 0x51 is just one byte at a time. Also SFF-8472 requires
      * that EEPROM supports atomic 16bit read operation for diagnostic
      * fields, so do not switch to one byte reading at a time unless it
      * is really required and we have no other option.
      */
     if (sfp_id_needs_byte_io(sfp, &id.base, sizeof(id.base))) {
         dev_info(sfp->dev,
              "Detected broken RTL8672/RTL9601C emulated EEPROM\n");
         dev_info(sfp->dev,
              "Switching to reading EEPROM to one byte at a time\n");
         sfp->i2c_block_size = 1;
 
         ret = sfp_read(sfp, false, 0, &id.base, sizeof(id.base));
         if (ret < 0) {
             if (report)
                 dev_err(sfp->dev,
                     "failed to read EEPROM: %pe\n",
                     ERR_PTR(ret));
             return -EAGAIN;
         }
 
         if (ret != sizeof(id.base)) {
             dev_err(sfp->dev, "EEPROM short read: %pe\n",
                 ERR_PTR(ret));
             return -EAGAIN;
         }
     }
 
     /* Cotsworks do not seem to update the checksums when they
      * do the final programming with the final module part number,
      * serial number and date code.
      */
     cotsworks = !memcmp(id.base.vendor_name, "COTSWORKS       ", 16);
     cotsworks_sfbg = !memcmp(id.base.vendor_pn, "SFBG", 4);
 
     /* Cotsworks SFF module EEPROM do not always have valid phys_id,
      * phys_ext_id, and connector bytes.  Rewrite SFF EEPROM bytes if
      * Cotsworks PN matches and bytes are not correct.
      */
     if (cotsworks && cotsworks_sfbg) {
         ret = sfp_cotsworks_fixup_check(sfp, &id);
         if (ret < 0)
             return ret;
     }
 
     /* Validate the checksum over the base structure */
     check = sfp_check(&id.base, sizeof(id.base) - 1);
     if (check != id.base.cc_base) {
         if (cotsworks) {
             dev_warn(sfp->dev,
                  "EEPROM base structure checksum failure (0x%02x != 0x%02x)\n",
                  check, id.base.cc_base);
         } else {
             dev_err(sfp->dev,
                 "EEPROM base structure checksum failure: 0x%02x != 0x%02x\n",
                 check, id.base.cc_base);
             print_hex_dump(KERN_ERR, "sfp EE: ", DUMP_PREFIX_OFFSET,
                        16, 1, &id, sizeof(id), true);
             return -EINVAL;
         }
     }
 
     ret = sfp_read(sfp, false, SFP_CC_BASE + 1, &id.ext, sizeof(id.ext));
     if (ret < 0) {
         if (report)
             dev_err(sfp->dev, "failed to read EEPROM: %pe\n",
                 ERR_PTR(ret));
         return -EAGAIN;
     }
 
     if (ret != sizeof(id.ext)) {
         dev_err(sfp->dev, "EEPROM short read: %pe\n", ERR_PTR(ret));
         return -EAGAIN;
     }
 
     check = sfp_check(&id.ext, sizeof(id.ext) - 1);
     if (check != id.ext.cc_ext) {
         if (cotsworks) {
             dev_warn(sfp->dev,
                  "EEPROM extended structure checksum failure (0x%02x != 0x%02x)\n",
                  check, id.ext.cc_ext);
         } else {
             dev_err(sfp->dev,
                 "EEPROM extended structure checksum failure: 0x%02x != 0x%02x\n",
                 check, id.ext.cc_ext);
             print_hex_dump(KERN_ERR, "sfp EE: ", DUMP_PREFIX_OFFSET,
                        16, 1, &id, sizeof(id), true);
             memset(&id.ext, 0, sizeof(id.ext));
         }
     }
 
     sfp->id = id;
 
     dev_info(sfp->dev, "module %.*s %.*s rev %.*s sn %.*s dc %.*s\n",
          (int)sizeof(id.base.vendor_name), id.base.vendor_name,
          (int)sizeof(id.base.vendor_pn), id.base.vendor_pn,
          (int)sizeof(id.base.vendor_rev), id.base.vendor_rev,
          (int)sizeof(id.ext.vendor_sn), id.ext.vendor_sn,
          (int)sizeof(id.ext.datecode), id.ext.datecode);
 
     /* Check whether we support this module */
     if (!sfp->type->module_supported(&id)) {
         dev_err(sfp->dev,
             "module is not supported - phys id 0x%02x 0x%02x\n",
             sfp->id.base.phys_id, sfp->id.base.phys_ext_id);
         return -EINVAL;
     }
 
     /* If the module requires address swap mode, warn about it */
     if (sfp->id.ext.diagmon & SFP_DIAGMON_ADDRMODE)
         dev_warn(sfp->dev,
              "module address swap to access page 0xA2 is not supported.\n");
 
     /* Parse the module power requirement */
     ret = sfp_module_parse_power(sfp);
     if (ret < 0)
         return ret;
 
     if (!memcmp(id.base.vendor_name, "ALCATELLUCENT   ", 16) &&
         !memcmp(id.base.vendor_pn, "3FE46541AA      ", 16))
         sfp->module_t_start_up = T_START_UP_BAD_GPON;
     else
         sfp->module_t_start_up = T_START_UP;
 
     if (!memcmp(id.base.vendor_name, "HUAWEI          ", 16) &&
         !memcmp(id.base.vendor_pn, "MA5671A         ", 16))
         sfp->tx_fault_ignore = true;
     else
         sfp->tx_fault_ignore = false;
 
     return 0;
 }
 
 static void sfp_sm_mod_remove(struct sfp *sfp)
 {
     if (sfp->sm_mod_state > SFP_MOD_WAITDEV)
         sfp_module_remove(sfp->sfp_bus);
 
     sfp_hwmon_remove(sfp);
 
     memset(&sfp->id, 0, sizeof(sfp->id));
     sfp->module_power_mW = 0;
 
     dev_info(sfp->dev, "module removed\n");
 }
 
 /* This state machine tracks the upstream's state */
 static void sfp_sm_device(struct sfp *sfp, unsigned int event)
 {
     switch (sfp->sm_dev_state) {
     default:
         if (event == SFP_E_DEV_ATTACH)
             sfp->sm_dev_state = SFP_DEV_DOWN;
         break;
 
     case SFP_DEV_DOWN:
         if (event == SFP_E_DEV_DETACH)
             sfp->sm_dev_state = SFP_DEV_DETACHED;
         else if (event == SFP_E_DEV_UP)
             sfp->sm_dev_state = SFP_DEV_UP;
         break;
 
     case SFP_DEV_UP:
         if (event == SFP_E_DEV_DETACH)
             sfp->sm_dev_state = SFP_DEV_DETACHED;
         else if (event == SFP_E_DEV_DOWN)
             sfp->sm_dev_state = SFP_DEV_DOWN;
         break;
     }
 }
 
 /* This state machine tracks the insert/remove state of the module, probes
  * the on-board EEPROM, and sets up the power level.
  */
 static void sfp_sm_module(struct sfp *sfp, unsigned int event)
 {
     int err;
 
     /* Handle remove event globally, it resets this state machine */
     if (event == SFP_E_REMOVE) {
         if (sfp->sm_mod_state > SFP_MOD_PROBE)
             sfp_sm_mod_remove(sfp);
         sfp_sm_mod_next(sfp, SFP_MOD_EMPTY, 0);
         return;
     }
 
     /* Handle device detach globally */
     if (sfp->sm_dev_state < SFP_DEV_DOWN &&
         sfp->sm_mod_state > SFP_MOD_WAITDEV) {
         if (sfp->module_power_mW > 1000 &&
             sfp->sm_mod_state > SFP_MOD_HPOWER)
             sfp_sm_mod_hpower(sfp, false);
         sfp_sm_mod_next(sfp, SFP_MOD_WAITDEV, 0);
         return;
     }
 
     switch (sfp->sm_mod_state) {
     default:
         if (event == SFP_E_INSERT) {
             sfp_sm_mod_next(sfp, SFP_MOD_PROBE, T_SERIAL);
             sfp->sm_mod_tries_init = R_PROBE_RETRY_INIT;
             sfp->sm_mod_tries = R_PROBE_RETRY_SLOW;
         }
         break;
 
     case SFP_MOD_PROBE:
         /* Wait for T_PROBE_INIT to time out */
         if (event != SFP_E_TIMEOUT)
             break;
 
         err = sfp_sm_mod_probe(sfp, sfp->sm_mod_tries == 1);
         if (err == -EAGAIN) {
             if (sfp->sm_mod_tries_init &&
                --sfp->sm_mod_tries_init) {
                 sfp_sm_set_timer(sfp, T_PROBE_RETRY_INIT);
                 break;
             } else if (sfp->sm_mod_tries && --sfp->sm_mod_tries) {
                 if (sfp->sm_mod_tries == R_PROBE_RETRY_SLOW - 1)
                     dev_warn(sfp->dev,
                          "please wait, module slow to respond\n");
                 sfp_sm_set_timer(sfp, T_PROBE_RETRY_SLOW);
                 break;
             }
         }
         if (err < 0) {
             sfp_sm_mod_next(sfp, SFP_MOD_ERROR, 0);
             break;
         }
 
         err = sfp_hwmon_insert(sfp);
         if (err)
             dev_warn(sfp->dev, "hwmon probe failed: %pe\n",
                  ERR_PTR(err));
 
         sfp_sm_mod_next(sfp, SFP_MOD_WAITDEV, 0);
         fallthrough;
     case SFP_MOD_WAITDEV:
         /* Ensure that the device is attached before proceeding */
         if (sfp->sm_dev_state < SFP_DEV_DOWN)
             break;
 
         /* Report the module insertion to the upstream device */
         err = sfp_module_insert(sfp->sfp_bus, &sfp->id);
         if (err < 0) {
             sfp_sm_mod_next(sfp, SFP_MOD_ERROR, 0);
             break;
         }
 
         /* If this is a power level 1 module, we are done */
         if (sfp->module_power_mW <= 1000)
             goto insert;
 
         sfp_sm_mod_next(sfp, SFP_MOD_HPOWER, 0);
         fallthrough;
     case SFP_MOD_HPOWER:
         /* Enable high power mode */
         err = sfp_sm_mod_hpower(sfp, true);
         if (err < 0) {
             if (err != -EAGAIN) {
                 sfp_module_remove(sfp->sfp_bus);
                 sfp_sm_mod_next(sfp, SFP_MOD_ERROR, 0);
             } else {
                 sfp_sm_set_timer(sfp, T_PROBE_RETRY_INIT);
             }
             break;
         }
 
         sfp_sm_mod_next(sfp, SFP_MOD_WAITPWR, T_HPOWER_LEVEL);
         break;
 
     case SFP_MOD_WAITPWR:
         /* Wait for T_HPOWER_LEVEL to time out */
         if (event != SFP_E_TIMEOUT)
             break;
 
     insert:
         sfp_sm_mod_next(sfp, SFP_MOD_PRESENT, 0);
         break;
 
     case SFP_MOD_PRESENT:
     case SFP_MOD_ERROR:
         break;
     }
 }
 
 static void sfp_sm_main(struct sfp *sfp, unsigned int event)
 {
     unsigned long timeout;
     int ret;
 
     /* Some events are global */
     if (sfp->sm_state != SFP_S_DOWN &&
         (sfp->sm_mod_state != SFP_MOD_PRESENT ||
          sfp->sm_dev_state != SFP_DEV_UP)) {
         if (sfp->sm_state == SFP_S_LINK_UP &&
             sfp->sm_dev_state == SFP_DEV_UP)
             sfp_sm_link_down(sfp);
         if (sfp->sm_state > SFP_S_INIT)
             sfp_module_stop(sfp->sfp_bus);
         if (sfp->mod_phy)
             sfp_sm_phy_detach(sfp);
         sfp_module_tx_disable(sfp);
         sfp_soft_stop_poll(sfp);
         sfp_sm_next(sfp, SFP_S_DOWN, 0);
         return;
     }
 
     /* The main state machine */
     switch (sfp->sm_state) {
     case SFP_S_DOWN:
         if (sfp->sm_mod_state != SFP_MOD_PRESENT ||
             sfp->sm_dev_state != SFP_DEV_UP)
             break;
 
         if (!(sfp->id.ext.diagmon & SFP_DIAGMON_ADDRMODE))
             sfp_soft_start_poll(sfp);
 
         sfp_module_tx_enable(sfp);
 
         /* Initialise the fault clearance retries */
         sfp->sm_fault_retries = N_FAULT_INIT;
 
         /* We need to check the TX_FAULT state, which is not defined
          * while TX_DISABLE is asserted. The earliest we want to do
          * anything (such as probe for a PHY) is 50ms.
          */
         sfp_sm_next(sfp, SFP_S_WAIT, T_WAIT);
         break;
 
     case SFP_S_WAIT:
         if (event != SFP_E_TIMEOUT)
             break;
 
         if (sfp->state & SFP_F_TX_FAULT) {
             /* Wait up to t_init (SFF-8472) or t_start_up (SFF-8431)
              * from the TX_DISABLE deassertion for the module to
              * initialise, which is indicated by TX_FAULT
              * deasserting.
              */
             timeout = sfp->module_t_start_up;
             if (timeout > T_WAIT)
                 timeout -= T_WAIT;
             else
                 timeout = 1;
 
             sfp_sm_next(sfp, SFP_S_INIT, timeout);
         } else {
             /* TX_FAULT is not asserted, assume the module has
              * finished initialising.
              */
             goto init_done;
         }
         break;
 
     case SFP_S_INIT:
         if (event == SFP_E_TIMEOUT && sfp->state & SFP_F_TX_FAULT) {
             /* TX_FAULT is still asserted after t_init
              * or t_start_up, so assume there is a fault.
              */
             sfp_sm_fault(sfp, SFP_S_INIT_TX_FAULT,
                      sfp->sm_fault_retries == N_FAULT_INIT);
         } else if (event == SFP_E_TIMEOUT || event == SFP_E_TX_CLEAR) {
     init_done:
             sfp->sm_phy_retries = R_PHY_RETRY;
             goto phy_probe;
         }
         break;
 
     case SFP_S_INIT_PHY:
         if (event != SFP_E_TIMEOUT)
             break;
     phy_probe:
         /* TX_FAULT deasserted or we timed out with TX_FAULT
          * clear.  Probe for the PHY and check the LOS state.
          */
         ret = sfp_sm_probe_for_phy(sfp);
         if (ret == -ENODEV) {
             if (--sfp->sm_phy_retries) {
                 sfp_sm_next(sfp, SFP_S_INIT_PHY, T_PHY_RETRY);
                 break;
             } else {
                 dev_info(sfp->dev, "no PHY detected\n");
             }
         } else if (ret) {
             sfp_sm_next(sfp, SFP_S_FAIL, 0);
             break;
         }
         if (sfp_module_start(sfp->sfp_bus)) {
             sfp_sm_next(sfp, SFP_S_FAIL, 0);
             break;
         }
         sfp_sm_link_check_los(sfp);
 
         /* Reset the fault retry count */
         sfp->sm_fault_retries = N_FAULT;
         break;
 
     case SFP_S_INIT_TX_FAULT:
         if (event == SFP_E_TIMEOUT) {
             sfp_module_tx_fault_reset(sfp);
             sfp_sm_next(sfp, SFP_S_INIT, sfp->module_t_start_up);
         }
         break;
 
     case SFP_S_WAIT_LOS:
         if (event == SFP_E_TX_FAULT)
             sfp_sm_fault(sfp, SFP_S_TX_FAULT, true);
         else if (sfp_los_event_inactive(sfp, event))
             sfp_sm_link_up(sfp);
         break;
 
     case SFP_S_LINK_UP:
         if (event == SFP_E_TX_FAULT) {
             sfp_sm_link_down(sfp);
             sfp_sm_fault(sfp, SFP_S_TX_FAULT, true);
         } else if (sfp_los_event_active(sfp, event)) {
             sfp_sm_link_down(sfp);
             sfp_sm_next(sfp, SFP_S_WAIT_LOS, 0);
         }
         break;
 
     case SFP_S_TX_FAULT:
         if (event == SFP_E_TIMEOUT) {
             sfp_module_tx_fault_reset(sfp);
             sfp_sm_next(sfp, SFP_S_REINIT, sfp->module_t_start_up);
         }
         break;
 
     case SFP_S_REINIT:
         if (event == SFP_E_TIMEOUT && sfp->state & SFP_F_TX_FAULT) {
             sfp_sm_fault(sfp, SFP_S_TX_FAULT, false);
         } else if (event == SFP_E_TIMEOUT || event == SFP_E_TX_CLEAR) {
             dev_info(sfp->dev, "module transmit fault recovered\n");
             sfp_sm_link_check_los(sfp);
         }
         break;
 
     case SFP_S_TX_DISABLE:
         break;
     }
 }
 
 static void sfp_sm_event(struct sfp *sfp, unsigned int event)
 {
     mutex_lock(&sfp->sm_mutex);
 
     dev_dbg(sfp->dev, "SM: enter %s:%s:%s event %s\n",
         mod_state_to_str(sfp->sm_mod_state),
         dev_state_to_str(sfp->sm_dev_state),
         sm_state_to_str(sfp->sm_state),
         event_to_str(event));
 
     sfp_sm_device(sfp, event);
     sfp_sm_module(sfp, event);
     sfp_sm_main(sfp, event);
 
     dev_dbg(sfp->dev, "SM: exit %s:%s:%s\n",
         mod_state_to_str(sfp->sm_mod_state),
         dev_state_to_str(sfp->sm_dev_state),
         sm_state_to_str(sfp->sm_state));
 
     mutex_unlock(&sfp->sm_mutex);
 }
 
 static void sfp_attach(struct sfp *sfp)
 {
     sfp_sm_event(sfp, SFP_E_DEV_ATTACH);
 }
 
 static void sfp_detach(struct sfp *sfp)
 {
     sfp_sm_event(sfp, SFP_E_DEV_DETACH);
 }
 
 static void sfp_start(struct sfp *sfp)
 {
     sfp_sm_event(sfp, SFP_E_DEV_UP);
 }
 
 static void sfp_stop(struct sfp *sfp)
 {
     sfp_sm_event(sfp, SFP_E_DEV_DOWN);
 }
 
 static int sfp_module_info(struct sfp *sfp, struct ethtool_modinfo *modinfo)
 {
     /* locking... and check module is present */
 
     if (sfp->id.ext.sff8472_compliance &&
         !(sfp->id.ext.diagmon & SFP_DIAGMON_ADDRMODE)) {
         modinfo->type = ETH_MODULE_SFF_8472;
         modinfo->eeprom_len = ETH_MODULE_SFF_8472_LEN;
     } else {
         modinfo->type = ETH_MODULE_SFF_8079;
         modinfo->eeprom_len = ETH_MODULE_SFF_8079_LEN;
     }
     return 0;
 }
 
 static int sfp_module_eeprom(struct sfp *sfp, struct ethtool_eeprom *ee,
                  u8 *data)
 {
     unsigned int first, last, len;
     int ret;
 
     if (ee->len == 0)
         return -EINVAL;
 
     first = ee->offset;
     last = ee->offset + ee->len;
     if (first < ETH_MODULE_SFF_8079_LEN) {
         len = min_t(unsigned int, last, ETH_MODULE_SFF_8079_LEN);
         len -= first;
 
         ret = sfp_read(sfp, false, first, data, len);
         if (ret < 0)
             return ret;
 
         first += len;
         data += len;
     }
     if (first < ETH_MODULE_SFF_8472_LEN && last > ETH_MODULE_SFF_8079_LEN) {
         len = min_t(unsigned int, last, ETH_MODULE_SFF_8472_LEN);
         len -= first;
         first -= ETH_MODULE_SFF_8079_LEN;
 
         ret = sfp_read(sfp, true, first, data, len);
         if (ret < 0)
             return ret;
     }
     return 0;
 }
 
 static int sfp_module_eeprom_by_page(struct sfp *sfp,
                      const struct ethtool_module_eeprom *page,
                      struct netlink_ext_ack *extack)
 {
     if (page->bank) {
         NL_SET_ERR_MSG(extack, "Banks not supported");
         return -EOPNOTSUPP;
     }
 
     if (page->page) {
         NL_SET_ERR_MSG(extack, "Only page 0 supported");
         return -EOPNOTSUPP;
     }
 
     if (page->i2c_address != 0x50 &&
         page->i2c_address != 0x51) {
         NL_SET_ERR_MSG(extack, "Only address 0x50 and 0x51 supported");
         return -EOPNOTSUPP;
     }
 
     return sfp_read(sfp, page->i2c_address == 0x51, page->offset,
             page->data, page->length);
 };
 
 static const struct sfp_socket_ops sfp_module_ops = {
     .attach = sfp_attach,
     .detach = sfp_detach,
     .start = sfp_start,
     .stop = sfp_stop,
     .module_info = sfp_module_info,
     .module_eeprom = sfp_module_eeprom,
     .module_eeprom_by_page = sfp_module_eeprom_by_page,
 };
 
 static void sfp_timeout(struct work_struct *work)
 {
     struct sfp *sfp = container_of(work, struct sfp, timeout.work);
 
     rtnl_lock();
     sfp_sm_event(sfp, SFP_E_TIMEOUT);
     rtnl_unlock();
 }
 
 static void sfp_check_state(struct sfp *sfp)
 {
     unsigned int state, i, changed;
 
     mutex_lock(&sfp->st_mutex);
     state = sfp_get_state(sfp);
     changed = state ^ sfp->state;
     if (sfp->tx_fault_ignore)
         changed &= SFP_F_PRESENT | SFP_F_LOS;
     else
         changed &= SFP_F_PRESENT | SFP_F_LOS | SFP_F_TX_FAULT;
 
     for (i = 0; i < GPIO_MAX; i++)
         if (changed & BIT(i))
             dev_dbg(sfp->dev, "%s %u -> %u\n", gpio_of_names[i],
                 !!(sfp->state & BIT(i)), !!(state & BIT(i)));
 
     state |= sfp->state & (SFP_F_TX_DISABLE | SFP_F_RATE_SELECT);
     sfp->state = state;
 
     rtnl_lock();
     if (changed & SFP_F_PRESENT)
         sfp_sm_event(sfp, state & SFP_F_PRESENT ?
                 SFP_E_INSERT : SFP_E_REMOVE);
 
     if (changed & SFP_F_TX_FAULT)
         sfp_sm_event(sfp, state & SFP_F_TX_FAULT ?
                 SFP_E_TX_FAULT : SFP_E_TX_CLEAR);
 
     if (changed & SFP_F_LOS)
         sfp_sm_event(sfp, state & SFP_F_LOS ?
                 SFP_E_LOS_HIGH : SFP_E_LOS_LOW);
     rtnl_unlock();
     mutex_unlock(&sfp->st_mutex);
 }
 
 static irqreturn_t sfp_irq(int irq, void *data)
 {
     struct sfp *sfp = data;
 
     sfp_check_state(sfp);
 
     return IRQ_HANDLED;
 }
 
 static void sfp_poll(struct work_struct *work)
 {
     struct sfp *sfp = container_of(work, struct sfp, poll.work);
 
     sfp_check_state(sfp);
 
     if (sfp->state_soft_mask & (SFP_F_LOS | SFP_F_TX_FAULT) ||
         sfp->need_poll)
         mod_delayed_work(system_wq, &sfp->poll, poll_jiffies);
 }
 
 static struct sfp *sfp_alloc(struct device *dev)
 {
     struct sfp *sfp;
 
     sfp = kzalloc(sizeof(*sfp), GFP_KERNEL);
     if (!sfp)
         return ERR_PTR(-ENOMEM);
 
     sfp->dev = dev;
 
     mutex_init(&sfp->sm_mutex);
     mutex_init(&sfp->st_mutex);
     INIT_DELAYED_WORK(&sfp->poll, sfp_poll);
     INIT_DELAYED_WORK(&sfp->timeout, sfp_timeout);
 
     sfp_hwmon_init(sfp);
 
     return sfp;
 }
 
 static void sfp_cleanup(void *data)
 {
     struct sfp *sfp = data;
 
     sfp_hwmon_exit(sfp);
 
     cancel_delayed_work_sync(&sfp->poll);
     cancel_delayed_work_sync(&sfp->timeout);
     if (sfp->i2c_mii) {
         mdiobus_unregister(sfp->i2c_mii);
         mdiobus_free(sfp->i2c_mii);
     }
     if (sfp->i2c)
         i2c_put_adapter(sfp->i2c);
     kfree(sfp);
 }
 
 static int sfp_probe(struct platform_device *pdev)
 {
     const struct sff_data *sff;
     struct i2c_adapter *i2c;
     char *sfp_irq_name;
     struct sfp *sfp;
     int err, i;
 
     sfp = sfp_alloc(&pdev->dev);
     if (IS_ERR(sfp))
         return PTR_ERR(sfp);
 
     platform_set_drvdata(pdev, sfp);
 
     err = devm_add_action_or_reset(sfp->dev, sfp_cleanup, sfp);
     if (err < 0)
         return err;
 
     sff = sfp->type = &sfp_data;
 
     if (pdev->dev.of_node) {
         struct device_node *node = pdev->dev.of_node;
         const struct of_device_id *id;
         struct device_node *np;
 
         id = of_match_node(sfp_of_match, node);
         if (WARN_ON(!id))
             return -EINVAL;
 
         sff = sfp->type = id->data;
 
         np = of_parse_phandle(node, "i2c-bus", 0);
         if (!np) {
             dev_err(sfp->dev, "missing 'i2c-bus' property\n");
             return -ENODEV;
         }
 
         i2c = of_find_i2c_adapter_by_node(np);
         of_node_put(np);
     } else if (has_acpi_companion(&pdev->dev)) {
         struct acpi_device *adev = ACPI_COMPANION(&pdev->dev);
         struct fwnode_handle *fw = acpi_fwnode_handle(adev);
         struct fwnode_reference_args args;
         struct acpi_handle *acpi_handle;
         int ret;
 
         ret = acpi_node_get_property_reference(fw, "i2c-bus", 0, &args);
         if (ret || !is_acpi_device_node(args.fwnode)) {
             dev_err(&pdev->dev, "missing 'i2c-bus' property\n");
             return -ENODEV;
         }
 
         acpi_handle = ACPI_HANDLE_FWNODE(args.fwnode);
         i2c = i2c_acpi_find_adapter_by_handle(acpi_handle);
     } else {
         return -EINVAL;
     }
 
     if (!i2c)
         return -EPROBE_DEFER;
 
     err = sfp_i2c_configure(sfp, i2c);
     if (err < 0) {
         i2c_put_adapter(i2c);
         return err;
     }
 
     for (i = 0; i < GPIO_MAX; i++)
         if (sff->gpios & BIT(i)) {
             sfp->gpio[i] = devm_gpiod_get_optional(sfp->dev,
                        gpio_of_names[i], gpio_flags[i]);
             if (IS_ERR(sfp->gpio[i]))
                 return PTR_ERR(sfp->gpio[i]);
         }
 
     sfp->get_state = sfp_gpio_get_state;
     sfp->set_state = sfp_gpio_set_state;
 
     /* Modules that have no detect signal are always present */
     if (!(sfp->gpio[GPIO_MODDEF0]))
         sfp->get_state = sff_gpio_get_state;
 
     device_property_read_u32(&pdev->dev, "maximum-power-milliwatt",
                  &sfp->max_power_mW);
     if (!sfp->max_power_mW)
         sfp->max_power_mW = 1000;
 
     dev_info(sfp->dev, "Host maximum power %u.%uW\n",
          sfp->max_power_mW / 1000, (sfp->max_power_mW / 100) % 10);
 
     /* Get the initial state, and always signal TX disable,
      * since the network interface will not be up.
      */
     sfp->state = sfp_get_state(sfp) | SFP_F_TX_DISABLE;
 
     if (sfp->gpio[GPIO_RATE_SELECT] &&
         gpiod_get_value_cansleep(sfp->gpio[GPIO_RATE_SELECT]))
         sfp->state |= SFP_F_RATE_SELECT;
     sfp_set_state(sfp, sfp->state);
     sfp_module_tx_disable(sfp);
     if (sfp->state & SFP_F_PRESENT) {
         rtnl_lock();
         sfp_sm_event(sfp, SFP_E_INSERT);
         rtnl_unlock();
     }
 
     for (i = 0; i < GPIO_MAX; i++) {
         if (gpio_flags[i] != GPIOD_IN || !sfp->gpio[i])
             continue;
 
         sfp->gpio_irq[i] = gpiod_to_irq(sfp->gpio[i]);
         if (sfp->gpio_irq[i] < 0) {
             sfp->gpio_irq[i] = 0;
             sfp->need_poll = true;
             continue;
         }
 
         sfp_irq_name = devm_kasprintf(sfp->dev, GFP_KERNEL,
                           "%s-%s", dev_name(sfp->dev),
                           gpio_of_names[i]);
 
         if (!sfp_irq_name)
             return -ENOMEM;
 
         err = devm_request_threaded_irq(sfp->dev, sfp->gpio_irq[i],
                         NULL, sfp_irq,
                         IRQF_ONESHOT |
                         IRQF_TRIGGER_RISING |
                         IRQF_TRIGGER_FALLING,
                         sfp_irq_name, sfp);
         if (err) {
             sfp->gpio_irq[i] = 0;
             sfp->need_poll = true;
         }
     }
 
     if (sfp->need_poll)
         mod_delayed_work(system_wq, &sfp->poll, poll_jiffies);
 
     /* We could have an issue in cases no Tx disable pin is available or
      * wired as modules using a laser as their light source will continue to
      * be active when the fiber is removed. This could be a safety issue and
      * we should at least warn the user about that.
      */
     if (!sfp->gpio[GPIO_TX_DISABLE])
         dev_warn(sfp->dev,
              "No tx_disable pin: SFP modules will always be emitting.\n");
 
     sfp->sfp_bus = sfp_register_socket(sfp->dev, sfp, &sfp_module_ops);
     if (!sfp->sfp_bus)
         return -ENOMEM;
 
     sfp_debugfs_init(sfp);
 
     return 0;
 }
 
 static int sfp_remove(struct platform_device *pdev)
 {
     struct sfp *sfp = platform_get_drvdata(pdev);
 
     sfp_debugfs_exit(sfp);
     sfp_unregister_socket(sfp->sfp_bus);
 
     rtnl_lock();
     sfp_sm_event(sfp, SFP_E_REMOVE);
     rtnl_unlock();
 
     return 0;
 }
 
 static void sfp_shutdown(struct platform_device *pdev)
 {
     struct sfp *sfp = platform_get_drvdata(pdev);
     int i;
 
     for (i = 0; i < GPIO_MAX; i++) {
         if (!sfp->gpio_irq[i])
             continue;
 
         devm_free_irq(sfp->dev, sfp->gpio_irq[i], sfp);
     }
 
     cancel_delayed_work_sync(&sfp->poll);
     cancel_delayed_work_sync(&sfp->timeout);
 }
 
 static struct platform_driver sfp_driver = {
     .probe = sfp_probe,
     .remove = sfp_remove,
     .shutdown = sfp_shutdown,
     .driver = {
         .name = "sfp",
         .of_match_table = sfp_of_match,
     },
 };
 
 static int sfp_init(void)
 {
     poll_jiffies = msecs_to_jiffies(100);
 
     return platform_driver_register(&sfp_driver);
 }
 module_init(sfp_init);
 
 static void sfp_exit(void)
 {
     platform_driver_unregister(&sfp_driver);
 }
 module_exit(sfp_exit);
 
 MODULE_ALIAS("platform:sfp");
 MODULE_AUTHOR("Russell King");
 MODULE_LICENSE("GPL v2");