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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 OR BSD-3-Clause)
 // Copyright(c) 2015-17 Intel Corporation.
 
 #include <linux/acpi.h>
 #include <linux/delay.h>
 #include <linux/mod_devicetable.h>
 #include <linux/pm_runtime.h>
 #include <linux/soundwire/sdw_registers.h>
 #include <linux/soundwire/sdw.h>
 #include <linux/soundwire/sdw_type.h>
 #include "bus.h"
 #include "sysfs_local.h"
 
 static DEFINE_IDA(sdw_ida);
 
 static int sdw_get_id(struct sdw_bus *bus)
 {
     int rc = ida_alloc(&sdw_ida, GFP_KERNEL);
 
     if (rc < 0)
         return rc;
 
     bus->id = rc;
     return 0;
 }
 
 /**
  * sdw_bus_master_add() - add a bus Master instance
  * @bus: bus instance
  * @parent: parent device
  * @fwnode: firmware node handle
  *
  * Initializes the bus instance, read properties and create child
  * devices.
  */
 int sdw_bus_master_add(struct sdw_bus *bus, struct device *parent,
                struct fwnode_handle *fwnode)
 {
     struct sdw_master_prop *prop = NULL;
     int ret;
 
     if (!parent) {
         pr_err("SoundWire parent device is not set\n");
         return -ENODEV;
     }
 
     ret = sdw_get_id(bus);
     if (ret < 0) {
         dev_err(parent, "Failed to get bus id\n");
         return ret;
     }
 
     ret = sdw_master_device_add(bus, parent, fwnode);
     if (ret < 0) {
         dev_err(parent, "Failed to add master device at link %d\n",
             bus->link_id);
         return ret;
     }
 
     if (!bus->ops) {
         dev_err(bus->dev, "SoundWire Bus ops are not set\n");
         return -EINVAL;
     }
 
     if (!bus->compute_params) {
         dev_err(bus->dev,
             "Bandwidth allocation not configured, compute_params no set\n");
         return -EINVAL;
     }
 
     mutex_init(&bus->msg_lock);
     mutex_init(&bus->bus_lock);
     INIT_LIST_HEAD(&bus->slaves);
     INIT_LIST_HEAD(&bus->m_rt_list);
 
     /*
      * Initialize multi_link flag
      * TODO: populate this flag by reading property from FW node
      */
     bus->multi_link = false;
     if (bus->ops->read_prop) {
         ret = bus->ops->read_prop(bus);
         if (ret < 0) {
             dev_err(bus->dev,
                 "Bus read properties failed:%d\n", ret);
             return ret;
         }
     }
 
     sdw_bus_debugfs_init(bus);
 
     /*
      * Device numbers in SoundWire are 0 through 15. Enumeration device
      * number (0), Broadcast device number (15), Group numbers (12 and
      * 13) and Master device number (14) are not used for assignment so
      * mask these and other higher bits.
      */
 
     /* Set higher order bits */
     *bus->assigned = ~GENMASK(SDW_BROADCAST_DEV_NUM, SDW_ENUM_DEV_NUM);
 
     /* Set enumuration device number and broadcast device number */
     set_bit(SDW_ENUM_DEV_NUM, bus->assigned);
     set_bit(SDW_BROADCAST_DEV_NUM, bus->assigned);
 
     /* Set group device numbers and master device number */
     set_bit(SDW_GROUP12_DEV_NUM, bus->assigned);
     set_bit(SDW_GROUP13_DEV_NUM, bus->assigned);
     set_bit(SDW_MASTER_DEV_NUM, bus->assigned);
 
     /*
      * SDW is an enumerable bus, but devices can be powered off. So,
      * they won't be able to report as present.
      *
      * Create Slave devices based on Slaves described in
      * the respective firmware (ACPI/DT)
      */
     if (IS_ENABLED(CONFIG_ACPI) && ACPI_HANDLE(bus->dev))
         ret = sdw_acpi_find_slaves(bus);
     else if (IS_ENABLED(CONFIG_OF) && bus->dev->of_node)
         ret = sdw_of_find_slaves(bus);
     else
         ret = -ENOTSUPP; /* No ACPI/DT so error out */
 
     if (ret < 0) {
         dev_err(bus->dev, "Finding slaves failed:%d\n", ret);
         return ret;
     }
 
     /*
      * Initialize clock values based on Master properties. The max
      * frequency is read from max_clk_freq property. Current assumption
      * is that the bus will start at highest clock frequency when
      * powered on.
      *
      * Default active bank will be 0 as out of reset the Slaves have
      * to start with bank 0 (Table 40 of Spec)
      */
     prop = &bus->prop;
     bus->params.max_dr_freq = prop->max_clk_freq * SDW_DOUBLE_RATE_FACTOR;
     bus->params.curr_dr_freq = bus->params.max_dr_freq;
     bus->params.curr_bank = SDW_BANK0;
     bus->params.next_bank = SDW_BANK1;
 
     return 0;
 }
 EXPORT_SYMBOL(sdw_bus_master_add);
 
 static int sdw_delete_slave(struct device *dev, void *data)
 {
     struct sdw_slave *slave = dev_to_sdw_dev(dev);
     struct sdw_bus *bus = slave->bus;
 
     pm_runtime_disable(dev);
 
     sdw_slave_debugfs_exit(slave);
 
     mutex_lock(&bus->bus_lock);
 
     if (slave->dev_num) /* clear dev_num if assigned */
         clear_bit(slave->dev_num, bus->assigned);
 
     list_del_init(&slave->node);
     mutex_unlock(&bus->bus_lock);
 
     device_unregister(dev);
     return 0;
 }
 
 /**
  * sdw_bus_master_delete() - delete the bus master instance
  * @bus: bus to be deleted
  *
  * Remove the instance, delete the child devices.
  */
 void sdw_bus_master_delete(struct sdw_bus *bus)
 {
     device_for_each_child(bus->dev, NULL, sdw_delete_slave);
     sdw_master_device_del(bus);
 
     sdw_bus_debugfs_exit(bus);
     ida_free(&sdw_ida, bus->id);
 }
 EXPORT_SYMBOL(sdw_bus_master_delete);
 
 /*
  * SDW IO Calls
  */
 
 static inline int find_response_code(enum sdw_command_response resp)
 {
     switch (resp) {
     case SDW_CMD_OK:
         return 0;
 
     case SDW_CMD_IGNORED:
         return -ENODATA;
 
     case SDW_CMD_TIMEOUT:
         return -ETIMEDOUT;
 
     default:
         return -EIO;
     }
 }
 
 static inline int do_transfer(struct sdw_bus *bus, struct sdw_msg *msg)
 {
     int retry = bus->prop.err_threshold;
     enum sdw_command_response resp;
     int ret = 0, i;
 
     for (i = 0; i <= retry; i++) {
         resp = bus->ops->xfer_msg(bus, msg);
         ret = find_response_code(resp);
 
         /* if cmd is ok or ignored return */
         if (ret == 0 || ret == -ENODATA)
             return ret;
     }
 
     return ret;
 }
 
 static inline int do_transfer_defer(struct sdw_bus *bus,
                     struct sdw_msg *msg,
                     struct sdw_defer *defer)
 {
     int retry = bus->prop.err_threshold;
     enum sdw_command_response resp;
     int ret = 0, i;
 
     defer->msg = msg;
     defer->length = msg->len;
     init_completion(&defer->complete);
 
     for (i = 0; i <= retry; i++) {
         resp = bus->ops->xfer_msg_defer(bus, msg, defer);
         ret = find_response_code(resp);
         /* if cmd is ok or ignored return */
         if (ret == 0 || ret == -ENODATA)
             return ret;
     }
 
     return ret;
 }
 
 static int sdw_reset_page(struct sdw_bus *bus, u16 dev_num)
 {
     int retry = bus->prop.err_threshold;
     enum sdw_command_response resp;
     int ret = 0, i;
 
     for (i = 0; i <= retry; i++) {
         resp = bus->ops->reset_page_addr(bus, dev_num);
         ret = find_response_code(resp);
         /* if cmd is ok or ignored return */
         if (ret == 0 || ret == -ENODATA)
             return ret;
     }
 
     return ret;
 }
 
 static int sdw_transfer_unlocked(struct sdw_bus *bus, struct sdw_msg *msg)
 {
     int ret;
 
     ret = do_transfer(bus, msg);
     if (ret != 0 && ret != -ENODATA)
         dev_err(bus->dev, "trf on Slave %d failed:%d %s addr %x count %d\n",
             msg->dev_num, ret,
             (msg->flags & SDW_MSG_FLAG_WRITE) ? "write" : "read",
             msg->addr, msg->len);
 
     if (msg->page)
         sdw_reset_page(bus, msg->dev_num);
 
     return ret;
 }
 
 /**
  * sdw_transfer() - Synchronous transfer message to a SDW Slave device
  * @bus: SDW bus
  * @msg: SDW message to be xfered
  */
 int sdw_transfer(struct sdw_bus *bus, struct sdw_msg *msg)
 {
     int ret;
 
     mutex_lock(&bus->msg_lock);
 
     ret = sdw_transfer_unlocked(bus, msg);
 
     mutex_unlock(&bus->msg_lock);
 
     return ret;
 }
 
 /**
  * sdw_transfer_defer() - Asynchronously transfer message to a SDW Slave device
  * @bus: SDW bus
  * @msg: SDW message to be xfered
  * @defer: Defer block for signal completion
  *
  * Caller needs to hold the msg_lock lock while calling this
  */
 int sdw_transfer_defer(struct sdw_bus *bus, struct sdw_msg *msg,
                struct sdw_defer *defer)
 {
     int ret;
 
     if (!bus->ops->xfer_msg_defer)
         return -ENOTSUPP;
 
     ret = do_transfer_defer(bus, msg, defer);
     if (ret != 0 && ret != -ENODATA)
         dev_err(bus->dev, "Defer trf on Slave %d failed:%d\n",
             msg->dev_num, ret);
 
     if (msg->page)
         sdw_reset_page(bus, msg->dev_num);
 
     return ret;
 }
 
 int sdw_fill_msg(struct sdw_msg *msg, struct sdw_slave *slave,
          u32 addr, size_t count, u16 dev_num, u8 flags, u8 *buf)
 {
     memset(msg, 0, sizeof(*msg));
     msg->addr = addr; /* addr is 16 bit and truncated here */
     msg->len = count;
     msg->dev_num = dev_num;
     msg->flags = flags;
     msg->buf = buf;
 
     if (addr < SDW_REG_NO_PAGE) /* no paging area */
         return 0;
 
     if (addr >= SDW_REG_MAX) { /* illegal addr */
         pr_err("SDW: Invalid address %x passed\n", addr);
         return -EINVAL;
     }
 
     if (addr < SDW_REG_OPTIONAL_PAGE) { /* 32k but no page */
         if (slave && !slave->prop.paging_support)
             return 0;
         /* no need for else as that will fall-through to paging */
     }
 
     /* paging mandatory */
     if (dev_num == SDW_ENUM_DEV_NUM || dev_num == SDW_BROADCAST_DEV_NUM) {
         pr_err("SDW: Invalid device for paging :%d\n", dev_num);
         return -EINVAL;
     }
 
     if (!slave) {
         pr_err("SDW: No slave for paging addr\n");
         return -EINVAL;
     }
 
     if (!slave->prop.paging_support) {
         dev_err(&slave->dev,
             "address %x needs paging but no support\n", addr);
         return -EINVAL;
     }
 
     msg->addr_page1 = FIELD_GET(SDW_SCP_ADDRPAGE1_MASK, addr);
     msg->addr_page2 = FIELD_GET(SDW_SCP_ADDRPAGE2_MASK, addr);
     msg->addr |= BIT(15);
     msg->page = true;
 
     return 0;
 }
 
 /*
  * Read/Write IO functions.
  * no_pm versions can only be called by the bus, e.g. while enumerating or
  * handling suspend-resume sequences.
  * all clients need to use the pm versions
  */
 
 static int
 sdw_nread_no_pm(struct sdw_slave *slave, u32 addr, size_t count, u8 *val)
 {
     struct sdw_msg msg;
     int ret;
 
     ret = sdw_fill_msg(&msg, slave, addr, count,
                slave->dev_num, SDW_MSG_FLAG_READ, val);
     if (ret < 0)
         return ret;
 
     ret = sdw_transfer(slave->bus, &msg);
     if (slave->is_mockup_device)
         ret = 0;
     return ret;
 }
 
 static int
 sdw_nwrite_no_pm(struct sdw_slave *slave, u32 addr, size_t count, const u8 *val)
 {
     struct sdw_msg msg;
     int ret;
 
     ret = sdw_fill_msg(&msg, slave, addr, count,
                slave->dev_num, SDW_MSG_FLAG_WRITE, (u8 *)val);
     if (ret < 0)
         return ret;
 
     ret = sdw_transfer(slave->bus, &msg);
     if (slave->is_mockup_device)
         ret = 0;
     return ret;
 }
 
 int sdw_write_no_pm(struct sdw_slave *slave, u32 addr, u8 value)
 {
     return sdw_nwrite_no_pm(slave, addr, 1, &value);
 }
 EXPORT_SYMBOL(sdw_write_no_pm);
 
 static int
 sdw_bread_no_pm(struct sdw_bus *bus, u16 dev_num, u32 addr)
 {
     struct sdw_msg msg;
     u8 buf;
     int ret;
 
     ret = sdw_fill_msg(&msg, NULL, addr, 1, dev_num,
                SDW_MSG_FLAG_READ, &buf);
     if (ret < 0)
         return ret;
 
     ret = sdw_transfer(bus, &msg);
     if (ret < 0)
         return ret;
 
     return buf;
 }
 
 static int
 sdw_bwrite_no_pm(struct sdw_bus *bus, u16 dev_num, u32 addr, u8 value)
 {
     struct sdw_msg msg;
     int ret;
 
     ret = sdw_fill_msg(&msg, NULL, addr, 1, dev_num,
                SDW_MSG_FLAG_WRITE, &value);
     if (ret < 0)
         return ret;
 
     return sdw_transfer(bus, &msg);
 }
 
 int sdw_bread_no_pm_unlocked(struct sdw_bus *bus, u16 dev_num, u32 addr)
 {
     struct sdw_msg msg;
     u8 buf;
     int ret;
 
     ret = sdw_fill_msg(&msg, NULL, addr, 1, dev_num,
                SDW_MSG_FLAG_READ, &buf);
     if (ret < 0)
         return ret;
 
     ret = sdw_transfer_unlocked(bus, &msg);
     if (ret < 0)
         return ret;
 
     return buf;
 }
 EXPORT_SYMBOL(sdw_bread_no_pm_unlocked);
 
 int sdw_bwrite_no_pm_unlocked(struct sdw_bus *bus, u16 dev_num, u32 addr, u8 value)
 {
     struct sdw_msg msg;
     int ret;
 
     ret = sdw_fill_msg(&msg, NULL, addr, 1, dev_num,
                SDW_MSG_FLAG_WRITE, &value);
     if (ret < 0)
         return ret;
 
     return sdw_transfer_unlocked(bus, &msg);
 }
 EXPORT_SYMBOL(sdw_bwrite_no_pm_unlocked);
 
 int sdw_read_no_pm(struct sdw_slave *slave, u32 addr)
 {
     u8 buf;
     int ret;
 
     ret = sdw_nread_no_pm(slave, addr, 1, &buf);
     if (ret < 0)
         return ret;
     else
         return buf;
 }
 EXPORT_SYMBOL(sdw_read_no_pm);
 
 int sdw_update_no_pm(struct sdw_slave *slave, u32 addr, u8 mask, u8 val)
 {
     int tmp;
 
     tmp = sdw_read_no_pm(slave, addr);
     if (tmp < 0)
         return tmp;
 
     tmp = (tmp & ~mask) | val;
     return sdw_write_no_pm(slave, addr, tmp);
 }
 EXPORT_SYMBOL(sdw_update_no_pm);
 
 /* Read-Modify-Write Slave register */
 int sdw_update(struct sdw_slave *slave, u32 addr, u8 mask, u8 val)
 {
     int tmp;
 
     tmp = sdw_read(slave, addr);
     if (tmp < 0)
         return tmp;
 
     tmp = (tmp & ~mask) | val;
     return sdw_write(slave, addr, tmp);
 }
 EXPORT_SYMBOL(sdw_update);
 
 /**
  * sdw_nread() - Read "n" contiguous SDW Slave registers
  * @slave: SDW Slave
  * @addr: Register address
  * @count: length
  * @val: Buffer for values to be read
  */
 int sdw_nread(struct sdw_slave *slave, u32 addr, size_t count, u8 *val)
 {
     int ret;
 
     ret = pm_runtime_resume_and_get(&slave->dev);
     if (ret < 0 && ret != -EACCES)
         return ret;
 
     ret = sdw_nread_no_pm(slave, addr, count, val);
 
     pm_runtime_mark_last_busy(&slave->dev);
     pm_runtime_put(&slave->dev);
 
     return ret;
 }
 EXPORT_SYMBOL(sdw_nread);
 
 /**
  * sdw_nwrite() - Write "n" contiguous SDW Slave registers
  * @slave: SDW Slave
  * @addr: Register address
  * @count: length
  * @val: Buffer for values to be written
  */
 int sdw_nwrite(struct sdw_slave *slave, u32 addr, size_t count, const u8 *val)
 {
     int ret;
 
     ret = pm_runtime_resume_and_get(&slave->dev);
     if (ret < 0 && ret != -EACCES)
         return ret;
 
     ret = sdw_nwrite_no_pm(slave, addr, count, val);
 
     pm_runtime_mark_last_busy(&slave->dev);
     pm_runtime_put(&slave->dev);
 
     return ret;
 }
 EXPORT_SYMBOL(sdw_nwrite);
 
 /**
  * sdw_read() - Read a SDW Slave register
  * @slave: SDW Slave
  * @addr: Register address
  */
 int sdw_read(struct sdw_slave *slave, u32 addr)
 {
     u8 buf;
     int ret;
 
     ret = sdw_nread(slave, addr, 1, &buf);
     if (ret < 0)
         return ret;
 
     return buf;
 }
 EXPORT_SYMBOL(sdw_read);
 
 /**
  * sdw_write() - Write a SDW Slave register
  * @slave: SDW Slave
  * @addr: Register address
  * @value: Register value
  */
 int sdw_write(struct sdw_slave *slave, u32 addr, u8 value)
 {
     return sdw_nwrite(slave, addr, 1, &value);
 }
 EXPORT_SYMBOL(sdw_write);
 
 /*
  * SDW alert handling
  */
 
 /* called with bus_lock held */
 static struct sdw_slave *sdw_get_slave(struct sdw_bus *bus, int i)
 {
     struct sdw_slave *slave;
 
     list_for_each_entry(slave, &bus->slaves, node) {
         if (slave->dev_num == i)
             return slave;
     }
 
     return NULL;
 }
 
 int sdw_compare_devid(struct sdw_slave *slave, struct sdw_slave_id id)
 {
     if (slave->id.mfg_id != id.mfg_id ||
         slave->id.part_id != id.part_id ||
         slave->id.class_id != id.class_id ||
         (slave->id.unique_id != SDW_IGNORED_UNIQUE_ID &&
          slave->id.unique_id != id.unique_id))
         return -ENODEV;
 
     return 0;
 }
 EXPORT_SYMBOL(sdw_compare_devid);
 
 /* called with bus_lock held */
 static int sdw_get_device_num(struct sdw_slave *slave)
 {
     int bit;
 
     bit = find_first_zero_bit(slave->bus->assigned, SDW_MAX_DEVICES);
     if (bit == SDW_MAX_DEVICES) {
         bit = -ENODEV;
         goto err;
     }
 
     /*
      * Do not update dev_num in Slave data structure here,
      * Update once program dev_num is successful
      */
     set_bit(bit, slave->bus->assigned);
 
 err:
     return bit;
 }
 
 static int sdw_assign_device_num(struct sdw_slave *slave)
 {
     struct sdw_bus *bus = slave->bus;
     int ret, dev_num;
     bool new_device = false;
 
     /* check first if device number is assigned, if so reuse that */
     if (!slave->dev_num) {
         if (!slave->dev_num_sticky) {
             mutex_lock(&slave->bus->bus_lock);
             dev_num = sdw_get_device_num(slave);
             mutex_unlock(&slave->bus->bus_lock);
             if (dev_num < 0) {
                 dev_err(bus->dev, "Get dev_num failed: %d\n",
                     dev_num);
                 return dev_num;
             }
             slave->dev_num = dev_num;
             slave->dev_num_sticky = dev_num;
             new_device = true;
         } else {
             slave->dev_num = slave->dev_num_sticky;
         }
     }
 
     if (!new_device)
         dev_dbg(bus->dev,
             "Slave already registered, reusing dev_num:%d\n",
             slave->dev_num);
 
     /* Clear the slave->dev_num to transfer message on device 0 */
     dev_num = slave->dev_num;
     slave->dev_num = 0;
 
     ret = sdw_write_no_pm(slave, SDW_SCP_DEVNUMBER, dev_num);
     if (ret < 0) {
         dev_err(bus->dev, "Program device_num %d failed: %d\n",
             dev_num, ret);
         return ret;
     }
 
     /* After xfer of msg, restore dev_num */
     slave->dev_num = slave->dev_num_sticky;
 
     return 0;
 }
 
 void sdw_extract_slave_id(struct sdw_bus *bus,
               u64 addr, struct sdw_slave_id *id)
 {
     dev_dbg(bus->dev, "SDW Slave Addr: %llx\n", addr);
 
     id->sdw_version = SDW_VERSION(addr);
     id->unique_id = SDW_UNIQUE_ID(addr);
     id->mfg_id = SDW_MFG_ID(addr);
     id->part_id = SDW_PART_ID(addr);
     id->class_id = SDW_CLASS_ID(addr);
 
     dev_dbg(bus->dev,
         "SDW Slave class_id 0x%02x, mfg_id 0x%04x, part_id 0x%04x, unique_id 0x%x, version 0x%x\n",
         id->class_id, id->mfg_id, id->part_id, id->unique_id, id->sdw_version);
 }
 EXPORT_SYMBOL(sdw_extract_slave_id);
 
 static int sdw_program_device_num(struct sdw_bus *bus)
 {
     u8 buf[SDW_NUM_DEV_ID_REGISTERS] = {0};
     struct sdw_slave *slave, *_s;
     struct sdw_slave_id id;
     struct sdw_msg msg;
     bool found;
     int count = 0, ret;
     u64 addr;
 
     /* No Slave, so use raw xfer api */
     ret = sdw_fill_msg(&msg, NULL, SDW_SCP_DEVID_0,
                SDW_NUM_DEV_ID_REGISTERS, 0, SDW_MSG_FLAG_READ, buf);
     if (ret < 0)
         return ret;
 
     do {
         ret = sdw_transfer(bus, &msg);
         if (ret == -ENODATA) { /* end of device id reads */
             dev_dbg(bus->dev, "No more devices to enumerate\n");
             ret = 0;
             break;
         }
         if (ret < 0) {
             dev_err(bus->dev, "DEVID read fail:%d\n", ret);
             break;
         }
 
         /*
          * Construct the addr and extract. Cast the higher shift
          * bits to avoid truncation due to size limit.
          */
         addr = buf[5] | (buf[4] << 8) | (buf[3] << 16) |
             ((u64)buf[2] << 24) | ((u64)buf[1] << 32) |
             ((u64)buf[0] << 40);
 
         sdw_extract_slave_id(bus, addr, &id);
 
         found = false;
         /* Now compare with entries */
         list_for_each_entry_safe(slave, _s, &bus->slaves, node) {
             if (sdw_compare_devid(slave, id) == 0) {
                 found = true;
 
                 /*
                  * Assign a new dev_num to this Slave and
                  * not mark it present. It will be marked
                  * present after it reports ATTACHED on new
                  * dev_num
                  */
                 ret = sdw_assign_device_num(slave);
                 if (ret < 0) {
                     dev_err(bus->dev,
                         "Assign dev_num failed:%d\n",
                         ret);
                     return ret;
                 }
 
                 break;
             }
         }
 
         if (!found) {
             /* TODO: Park this device in Group 13 */
 
             /*
              * add Slave device even if there is no platform
              * firmware description. There will be no driver probe
              * but the user/integration will be able to see the
              * device, enumeration status and device number in sysfs
              */
             sdw_slave_add(bus, &id, NULL);
 
             dev_err(bus->dev, "Slave Entry not found\n");
         }
 
         count++;
 
         /*
          * Check till error out or retry (count) exhausts.
          * Device can drop off and rejoin during enumeration
          * so count till twice the bound.
          */
 
     } while (ret == 0 && count < (SDW_MAX_DEVICES * 2));
 
     return ret;
 }
 
 static void sdw_modify_slave_status(struct sdw_slave *slave,
                     enum sdw_slave_status status)
 {
     struct sdw_bus *bus = slave->bus;
 
     mutex_lock(&bus->bus_lock);
 
     dev_vdbg(bus->dev,
          "%s: changing status slave %d status %d new status %d\n",
          __func__, slave->dev_num, slave->status, status);
 
     if (status == SDW_SLAVE_UNATTACHED) {
         dev_dbg(&slave->dev,
             "%s: initializing enumeration and init completion for Slave %d\n",
             __func__, slave->dev_num);
 
         init_completion(&slave->enumeration_complete);
         init_completion(&slave->initialization_complete);
 
     } else if ((status == SDW_SLAVE_ATTACHED) &&
            (slave->status == SDW_SLAVE_UNATTACHED)) {
         dev_dbg(&slave->dev,
             "%s: signaling enumeration completion for Slave %d\n",
             __func__, slave->dev_num);
 
         complete(&slave->enumeration_complete);
     }
     slave->status = status;
     mutex_unlock(&bus->bus_lock);
 }
 
 static int sdw_slave_clk_stop_callback(struct sdw_slave *slave,
                        enum sdw_clk_stop_mode mode,
                        enum sdw_clk_stop_type type)
 {
     int ret = 0;
 
     mutex_lock(&slave->sdw_dev_lock);
 
     if (slave->probed)  {
         struct device *dev = &slave->dev;
         struct sdw_driver *drv = drv_to_sdw_driver(dev->driver);
 
         if (drv->ops && drv->ops->clk_stop)
             ret = drv->ops->clk_stop(slave, mode, type);
     }
 
     mutex_unlock(&slave->sdw_dev_lock);
 
     return ret;
 }
 
 static int sdw_slave_clk_stop_prepare(struct sdw_slave *slave,
                       enum sdw_clk_stop_mode mode,
                       bool prepare)
 {
     bool wake_en;
     u32 val = 0;
     int ret;
 
     wake_en = slave->prop.wake_capable;
 
     if (prepare) {
         val = SDW_SCP_SYSTEMCTRL_CLK_STP_PREP;
 
         if (mode == SDW_CLK_STOP_MODE1)
             val |= SDW_SCP_SYSTEMCTRL_CLK_STP_MODE1;
 
         if (wake_en)
             val |= SDW_SCP_SYSTEMCTRL_WAKE_UP_EN;
     } else {
         ret = sdw_read_no_pm(slave, SDW_SCP_SYSTEMCTRL);
         if (ret < 0) {
             if (ret != -ENODATA)
                 dev_err(&slave->dev, "SDW_SCP_SYSTEMCTRL read failed:%d\n", ret);
             return ret;
         }
         val = ret;
         val &= ~(SDW_SCP_SYSTEMCTRL_CLK_STP_PREP);
     }
 
     ret = sdw_write_no_pm(slave, SDW_SCP_SYSTEMCTRL, val);
 
     if (ret < 0 && ret != -ENODATA)
         dev_err(&slave->dev, "SDW_SCP_SYSTEMCTRL write failed:%d\n", ret);
 
     return ret;
 }
 
 static int sdw_bus_wait_for_clk_prep_deprep(struct sdw_bus *bus, u16 dev_num)
 {
     int retry = bus->clk_stop_timeout;
     int val;
 
     do {
         val = sdw_bread_no_pm(bus, dev_num, SDW_SCP_STAT);
         if (val < 0) {
             if (val != -ENODATA)
                 dev_err(bus->dev, "SDW_SCP_STAT bread failed:%d\n", val);
             return val;
         }
         val &= SDW_SCP_STAT_CLK_STP_NF;
         if (!val) {
             dev_dbg(bus->dev, "clock stop prep/de-prep done slave:%d\n",
                 dev_num);
             return 0;
         }
 
         usleep_range(1000, 1500);
         retry--;
     } while (retry);
 
     dev_err(bus->dev, "clock stop prep/de-prep failed slave:%d\n",
         dev_num);
 
     return -ETIMEDOUT;
 }
 
 /**
  * sdw_bus_prep_clk_stop: prepare Slave(s) for clock stop
  *
  * @bus: SDW bus instance
  *
  * Query Slave for clock stop mode and prepare for that mode.
  */
 int sdw_bus_prep_clk_stop(struct sdw_bus *bus)
 {
     bool simple_clk_stop = true;
     struct sdw_slave *slave;
     bool is_slave = false;
     int ret = 0;
 
     /*
      * In order to save on transition time, prepare
      * each Slave and then wait for all Slave(s) to be
      * prepared for clock stop.
      * If one of the Slave devices has lost sync and
      * replies with Command Ignored/-ENODATA, we continue
      * the loop
      */
     list_for_each_entry(slave, &bus->slaves, node) {
         if (!slave->dev_num)
             continue;
 
         if (slave->status != SDW_SLAVE_ATTACHED &&
             slave->status != SDW_SLAVE_ALERT)
             continue;
 
         /* Identify if Slave(s) are available on Bus */
         is_slave = true;
 
         ret = sdw_slave_clk_stop_callback(slave,
                           SDW_CLK_STOP_MODE0,
                           SDW_CLK_PRE_PREPARE);
         if (ret < 0 && ret != -ENODATA) {
             dev_err(&slave->dev, "clock stop pre-prepare cb failed:%d\n", ret);
             return ret;
         }
 
         /* Only prepare a Slave device if needed */
         if (!slave->prop.simple_clk_stop_capable) {
             simple_clk_stop = false;
 
             ret = sdw_slave_clk_stop_prepare(slave,
                              SDW_CLK_STOP_MODE0,
                              true);
             if (ret < 0 && ret != -ENODATA) {
                 dev_err(&slave->dev, "clock stop prepare failed:%d\n", ret);
                 return ret;
             }
         }
     }
 
     /* Skip remaining clock stop preparation if no Slave is attached */
     if (!is_slave)
         return 0;
 
     /*
      * Don't wait for all Slaves to be ready if they follow the simple
      * state machine
      */
     if (!simple_clk_stop) {
         ret = sdw_bus_wait_for_clk_prep_deprep(bus,
                                SDW_BROADCAST_DEV_NUM);
         /*
          * if there are no Slave devices present and the reply is
          * Command_Ignored/-ENODATA, we don't need to continue with the
          * flow and can just return here. The error code is not modified
          * and its handling left as an exercise for the caller.
          */
         if (ret < 0)
             return ret;
     }
 
     /* Inform slaves that prep is done */
     list_for_each_entry(slave, &bus->slaves, node) {
         if (!slave->dev_num)
             continue;
 
         if (slave->status != SDW_SLAVE_ATTACHED &&
             slave->status != SDW_SLAVE_ALERT)
             continue;
 
         ret = sdw_slave_clk_stop_callback(slave,
                           SDW_CLK_STOP_MODE0,
                           SDW_CLK_POST_PREPARE);
 
         if (ret < 0 && ret != -ENODATA) {
             dev_err(&slave->dev, "clock stop post-prepare cb failed:%d\n", ret);
             return ret;
         }
     }
 
     return 0;
 }
 EXPORT_SYMBOL(sdw_bus_prep_clk_stop);
 
 /**
  * sdw_bus_clk_stop: stop bus clock
  *
  * @bus: SDW bus instance
  *
  * After preparing the Slaves for clock stop, stop the clock by broadcasting
  * write to SCP_CTRL register.
  */
 int sdw_bus_clk_stop(struct sdw_bus *bus)
 {
     int ret;
 
     /*
      * broadcast clock stop now, attached Slaves will ACK this,
      * unattached will ignore
      */
     ret = sdw_bwrite_no_pm(bus, SDW_BROADCAST_DEV_NUM,
                    SDW_SCP_CTRL, SDW_SCP_CTRL_CLK_STP_NOW);
     if (ret < 0) {
         if (ret != -ENODATA)
             dev_err(bus->dev, "ClockStopNow Broadcast msg failed %d\n", ret);
         return ret;
     }
 
     return 0;
 }
 EXPORT_SYMBOL(sdw_bus_clk_stop);
 
 /**
  * sdw_bus_exit_clk_stop: Exit clock stop mode
  *
  * @bus: SDW bus instance
  *
  * This De-prepares the Slaves by exiting Clock Stop Mode 0. For the Slaves
  * exiting Clock Stop Mode 1, they will be de-prepared after they enumerate
  * back.
  */
 int sdw_bus_exit_clk_stop(struct sdw_bus *bus)
 {
     bool simple_clk_stop = true;
     struct sdw_slave *slave;
     bool is_slave = false;
     int ret;
 
     /*
      * In order to save on transition time, de-prepare
      * each Slave and then wait for all Slave(s) to be
      * de-prepared after clock resume.
      */
     list_for_each_entry(slave, &bus->slaves, node) {
         if (!slave->dev_num)
             continue;
 
         if (slave->status != SDW_SLAVE_ATTACHED &&
             slave->status != SDW_SLAVE_ALERT)
             continue;
 
         /* Identify if Slave(s) are available on Bus */
         is_slave = true;
 
         ret = sdw_slave_clk_stop_callback(slave, SDW_CLK_STOP_MODE0,
                           SDW_CLK_PRE_DEPREPARE);
         if (ret < 0)
             dev_warn(&slave->dev, "clock stop pre-deprepare cb failed:%d\n", ret);
 
         /* Only de-prepare a Slave device if needed */
         if (!slave->prop.simple_clk_stop_capable) {
             simple_clk_stop = false;
 
             ret = sdw_slave_clk_stop_prepare(slave, SDW_CLK_STOP_MODE0,
                              false);
 
             if (ret < 0)
                 dev_warn(&slave->dev, "clock stop deprepare failed:%d\n", ret);
         }
     }
 
     /* Skip remaining clock stop de-preparation if no Slave is attached */
     if (!is_slave)
         return 0;
 
     /*
      * Don't wait for all Slaves to be ready if they follow the simple
      * state machine
      */
     if (!simple_clk_stop) {
         ret = sdw_bus_wait_for_clk_prep_deprep(bus, SDW_BROADCAST_DEV_NUM);
         if (ret < 0)
             dev_warn(bus->dev, "clock stop deprepare wait failed:%d\n", ret);
     }
 
     list_for_each_entry(slave, &bus->slaves, node) {
         if (!slave->dev_num)
             continue;
 
         if (slave->status != SDW_SLAVE_ATTACHED &&
             slave->status != SDW_SLAVE_ALERT)
             continue;
 
         ret = sdw_slave_clk_stop_callback(slave, SDW_CLK_STOP_MODE0,
                           SDW_CLK_POST_DEPREPARE);
         if (ret < 0)
             dev_warn(&slave->dev, "clock stop post-deprepare cb failed:%d\n", ret);
     }
 
     return 0;
 }
 EXPORT_SYMBOL(sdw_bus_exit_clk_stop);
 
 int sdw_configure_dpn_intr(struct sdw_slave *slave,
                int port, bool enable, int mask)
 {
     u32 addr;
     int ret;
     u8 val = 0;
 
     if (slave->bus->params.s_data_mode != SDW_PORT_DATA_MODE_NORMAL) {
         dev_dbg(&slave->dev, "TEST FAIL interrupt %s\n",
             enable ? "on" : "off");
         mask |= SDW_DPN_INT_TEST_FAIL;
     }
 
     addr = SDW_DPN_INTMASK(port);
 
     /* Set/Clear port ready interrupt mask */
     if (enable) {
         val |= mask;
         val |= SDW_DPN_INT_PORT_READY;
     } else {
         val &= ~(mask);
         val &= ~SDW_DPN_INT_PORT_READY;
     }
 
     ret = sdw_update(slave, addr, (mask | SDW_DPN_INT_PORT_READY), val);
     if (ret < 0)
         dev_err(&slave->dev,
             "SDW_DPN_INTMASK write failed:%d\n", val);
 
     return ret;
 }
 
 static int sdw_slave_set_frequency(struct sdw_slave *slave)
 {
     u32 mclk_freq = slave->bus->prop.mclk_freq;
     u32 curr_freq = slave->bus->params.curr_dr_freq >> 1;
     unsigned int scale;
     u8 scale_index;
     u8 base;
     int ret;
 
     /*
      * frequency base and scale registers are required for SDCA
      * devices. They may also be used for 1.2+/non-SDCA devices,
      * but we will need a DisCo property to cover this case
      */
     if (!slave->id.class_id)
         return 0;
 
     if (!mclk_freq) {
         dev_err(&slave->dev,
             "no bus MCLK, cannot set SDW_SCP_BUS_CLOCK_BASE\n");
         return -EINVAL;
     }
 
     /*
      * map base frequency using Table 89 of SoundWire 1.2 spec.
      * The order of the tests just follows the specification, this
      * is not a selection between possible values or a search for
      * the best value but just a mapping.  Only one case per platform
      * is relevant.
      * Some BIOS have inconsistent values for mclk_freq but a
      * correct root so we force the mclk_freq to avoid variations.
      */
     if (!(19200000 % mclk_freq)) {
         mclk_freq = 19200000;
         base = SDW_SCP_BASE_CLOCK_19200000_HZ;
     } else if (!(24000000 % mclk_freq)) {
         mclk_freq = 24000000;
         base = SDW_SCP_BASE_CLOCK_24000000_HZ;
     } else if (!(24576000 % mclk_freq)) {
         mclk_freq = 24576000;
         base = SDW_SCP_BASE_CLOCK_24576000_HZ;
     } else if (!(22579200 % mclk_freq)) {
         mclk_freq = 22579200;
         base = SDW_SCP_BASE_CLOCK_22579200_HZ;
     } else if (!(32000000 % mclk_freq)) {
         mclk_freq = 32000000;
         base = SDW_SCP_BASE_CLOCK_32000000_HZ;
     } else {
         dev_err(&slave->dev,
             "Unsupported clock base, mclk %d\n",
             mclk_freq);
         return -EINVAL;
     }
 
     if (mclk_freq % curr_freq) {
         dev_err(&slave->dev,
             "mclk %d is not multiple of bus curr_freq %d\n",
             mclk_freq, curr_freq);
         return -EINVAL;
     }
 
     scale = mclk_freq / curr_freq;
 
     /*
      * map scale to Table 90 of SoundWire 1.2 spec - and check
      * that the scale is a power of two and maximum 64
      */
     scale_index = ilog2(scale);
 
     if (BIT(scale_index) != scale || scale_index > 6) {
         dev_err(&slave->dev,
             "No match found for scale %d, bus mclk %d curr_freq %d\n",
             scale, mclk_freq, curr_freq);
         return -EINVAL;
     }
     scale_index++;
 
     ret = sdw_write_no_pm(slave, SDW_SCP_BUS_CLOCK_BASE, base);
     if (ret < 0) {
         dev_err(&slave->dev,
             "SDW_SCP_BUS_CLOCK_BASE write failed:%d\n", ret);
         return ret;
     }
 
     /* initialize scale for both banks */
     ret = sdw_write_no_pm(slave, SDW_SCP_BUSCLOCK_SCALE_B0, scale_index);
     if (ret < 0) {
         dev_err(&slave->dev,
             "SDW_SCP_BUSCLOCK_SCALE_B0 write failed:%d\n", ret);
         return ret;
     }
     ret = sdw_write_no_pm(slave, SDW_SCP_BUSCLOCK_SCALE_B1, scale_index);
     if (ret < 0)
         dev_err(&slave->dev,
             "SDW_SCP_BUSCLOCK_SCALE_B1 write failed:%d\n", ret);
 
     dev_dbg(&slave->dev,
         "Configured bus base %d, scale %d, mclk %d, curr_freq %d\n",
         base, scale_index, mclk_freq, curr_freq);
 
     return ret;
 }
 
 static int sdw_initialize_slave(struct sdw_slave *slave)
 {
     struct sdw_slave_prop *prop = &slave->prop;
     int status;
     int ret;
     u8 val;
 
     ret = sdw_slave_set_frequency(slave);
     if (ret < 0)
         return ret;
 
     if (slave->bus->prop.quirks & SDW_MASTER_QUIRKS_CLEAR_INITIAL_CLASH) {
         /* Clear bus clash interrupt before enabling interrupt mask */
         status = sdw_read_no_pm(slave, SDW_SCP_INT1);
         if (status < 0) {
             dev_err(&slave->dev,
                 "SDW_SCP_INT1 (BUS_CLASH) read failed:%d\n", status);
             return status;
         }
         if (status & SDW_SCP_INT1_BUS_CLASH) {
             dev_warn(&slave->dev, "Bus clash detected before INT mask is enabled\n");
             ret = sdw_write_no_pm(slave, SDW_SCP_INT1, SDW_SCP_INT1_BUS_CLASH);
             if (ret < 0) {
                 dev_err(&slave->dev,
                     "SDW_SCP_INT1 (BUS_CLASH) write failed:%d\n", ret);
                 return ret;
             }
         }
     }
     if ((slave->bus->prop.quirks & SDW_MASTER_QUIRKS_CLEAR_INITIAL_PARITY) &&
         !(slave->prop.quirks & SDW_SLAVE_QUIRKS_INVALID_INITIAL_PARITY)) {
         /* Clear parity interrupt before enabling interrupt mask */
         status = sdw_read_no_pm(slave, SDW_SCP_INT1);
         if (status < 0) {
             dev_err(&slave->dev,
                 "SDW_SCP_INT1 (PARITY) read failed:%d\n", status);
             return status;
         }
         if (status & SDW_SCP_INT1_PARITY) {
             dev_warn(&slave->dev, "PARITY error detected before INT mask is enabled\n");
             ret = sdw_write_no_pm(slave, SDW_SCP_INT1, SDW_SCP_INT1_PARITY);
             if (ret < 0) {
                 dev_err(&slave->dev,
                     "SDW_SCP_INT1 (PARITY) write failed:%d\n", ret);
                 return ret;
             }
         }
     }
 
     /*
      * Set SCP_INT1_MASK register, typically bus clash and
      * implementation-defined interrupt mask. The Parity detection
      * may not always be correct on startup so its use is
      * device-dependent, it might e.g. only be enabled in
      * steady-state after a couple of frames.
      */
     val = slave->prop.scp_int1_mask;
 
     /* Enable SCP interrupts */
     ret = sdw_update_no_pm(slave, SDW_SCP_INTMASK1, val, val);
     if (ret < 0) {
         dev_err(&slave->dev,
             "SDW_SCP_INTMASK1 write failed:%d\n", ret);
         return ret;
     }
 
     /* No need to continue if DP0 is not present */
     if (!slave->prop.dp0_prop)
         return 0;
 
     /* Enable DP0 interrupts */
     val = prop->dp0_prop->imp_def_interrupts;
     val |= SDW_DP0_INT_PORT_READY | SDW_DP0_INT_BRA_FAILURE;
 
     ret = sdw_update_no_pm(slave, SDW_DP0_INTMASK, val, val);
     if (ret < 0)
         dev_err(&slave->dev,
             "SDW_DP0_INTMASK read failed:%d\n", ret);
     return ret;
 }
 
 static int sdw_handle_dp0_interrupt(struct sdw_slave *slave, u8 *slave_status)
 {
     u8 clear, impl_int_mask;
     int status, status2, ret, count = 0;
 
     status = sdw_read_no_pm(slave, SDW_DP0_INT);
     if (status < 0) {
         dev_err(&slave->dev,
             "SDW_DP0_INT read failed:%d\n", status);
         return status;
     }
 
     do {
         clear = status & ~SDW_DP0_INTERRUPTS;
 
         if (status & SDW_DP0_INT_TEST_FAIL) {
             dev_err(&slave->dev, "Test fail for port 0\n");
             clear |= SDW_DP0_INT_TEST_FAIL;
         }
 
         /*
          * Assumption: PORT_READY interrupt will be received only for
          * ports implementing Channel Prepare state machine (CP_SM)
          */
 
         if (status & SDW_DP0_INT_PORT_READY) {
             complete(&slave->port_ready[0]);
             clear |= SDW_DP0_INT_PORT_READY;
         }
 
         if (status & SDW_DP0_INT_BRA_FAILURE) {
             dev_err(&slave->dev, "BRA failed\n");
             clear |= SDW_DP0_INT_BRA_FAILURE;
         }
 
         impl_int_mask = SDW_DP0_INT_IMPDEF1 |
             SDW_DP0_INT_IMPDEF2 | SDW_DP0_INT_IMPDEF3;
 
         if (status & impl_int_mask) {
             clear |= impl_int_mask;
             *slave_status = clear;
         }
 
         /* clear the interrupts but don't touch reserved and SDCA_CASCADE fields */
         ret = sdw_write_no_pm(slave, SDW_DP0_INT, clear);
         if (ret < 0) {
             dev_err(&slave->dev,
                 "SDW_DP0_INT write failed:%d\n", ret);
             return ret;
         }
 
         /* Read DP0 interrupt again */
         status2 = sdw_read_no_pm(slave, SDW_DP0_INT);
         if (status2 < 0) {
             dev_err(&slave->dev,
                 "SDW_DP0_INT read failed:%d\n", status2);
             return status2;
         }
         /* filter to limit loop to interrupts identified in the first status read */
         status &= status2;
 
         count++;
 
         /* we can get alerts while processing so keep retrying */
     } while ((status & SDW_DP0_INTERRUPTS) && (count < SDW_READ_INTR_CLEAR_RETRY));
 
     if (count == SDW_READ_INTR_CLEAR_RETRY)
         dev_warn(&slave->dev, "Reached MAX_RETRY on DP0 read\n");
 
     return ret;
 }
 
 static int sdw_handle_port_interrupt(struct sdw_slave *slave,
                      int port, u8 *slave_status)
 {
     u8 clear, impl_int_mask;
     int status, status2, ret, count = 0;
     u32 addr;
 
     if (port == 0)
         return sdw_handle_dp0_interrupt(slave, slave_status);
 
     addr = SDW_DPN_INT(port);
     status = sdw_read_no_pm(slave, addr);
     if (status < 0) {
         dev_err(&slave->dev,
             "SDW_DPN_INT read failed:%d\n", status);
 
         return status;
     }
 
     do {
         clear = status & ~SDW_DPN_INTERRUPTS;
 
         if (status & SDW_DPN_INT_TEST_FAIL) {
             dev_err(&slave->dev, "Test fail for port:%d\n", port);
             clear |= SDW_DPN_INT_TEST_FAIL;
         }
 
         /*
          * Assumption: PORT_READY interrupt will be received only
          * for ports implementing CP_SM.
          */
         if (status & SDW_DPN_INT_PORT_READY) {
             complete(&slave->port_ready[port]);
             clear |= SDW_DPN_INT_PORT_READY;
         }
 
         impl_int_mask = SDW_DPN_INT_IMPDEF1 |
             SDW_DPN_INT_IMPDEF2 | SDW_DPN_INT_IMPDEF3;
 
         if (status & impl_int_mask) {
             clear |= impl_int_mask;
             *slave_status = clear;
         }
 
         /* clear the interrupt but don't touch reserved fields */
         ret = sdw_write_no_pm(slave, addr, clear);
         if (ret < 0) {
             dev_err(&slave->dev,
                 "SDW_DPN_INT write failed:%d\n", ret);
             return ret;
         }
 
         /* Read DPN interrupt again */
         status2 = sdw_read_no_pm(slave, addr);
         if (status2 < 0) {
             dev_err(&slave->dev,
                 "SDW_DPN_INT read failed:%d\n", status2);
             return status2;
         }
         /* filter to limit loop to interrupts identified in the first status read */
         status &= status2;
 
         count++;
 
         /* we can get alerts while processing so keep retrying */
     } while ((status & SDW_DPN_INTERRUPTS) && (count < SDW_READ_INTR_CLEAR_RETRY));
 
     if (count == SDW_READ_INTR_CLEAR_RETRY)
         dev_warn(&slave->dev, "Reached MAX_RETRY on port read");
 
     return ret;
 }
 
 static int sdw_handle_slave_alerts(struct sdw_slave *slave)
 {
     struct sdw_slave_intr_status slave_intr;
     u8 clear = 0, bit, port_status[15] = {0};
     int port_num, stat, ret, count = 0;
     unsigned long port;
     bool slave_notify;
     u8 sdca_cascade = 0;
     u8 buf, buf2[2], _buf, _buf2[2];
     bool parity_check;
     bool parity_quirk;
 
     sdw_modify_slave_status(slave, SDW_SLAVE_ALERT);
 
     ret = pm_runtime_resume_and_get(&slave->dev);
     if (ret < 0 && ret != -EACCES) {
         dev_err(&slave->dev, "Failed to resume device: %d\n", ret);
         return ret;
     }
 
     /* Read Intstat 1, Intstat 2 and Intstat 3 registers */
     ret = sdw_read_no_pm(slave, SDW_SCP_INT1);
     if (ret < 0) {
         dev_err(&slave->dev,
             "SDW_SCP_INT1 read failed:%d\n", ret);
         goto io_err;
     }
     buf = ret;
 
     ret = sdw_nread_no_pm(slave, SDW_SCP_INTSTAT2, 2, buf2);
     if (ret < 0) {
         dev_err(&slave->dev,
             "SDW_SCP_INT2/3 read failed:%d\n", ret);
         goto io_err;
     }
 
     if (slave->prop.is_sdca) {
         ret = sdw_read_no_pm(slave, SDW_DP0_INT);
         if (ret < 0) {
             dev_err(&slave->dev,
                 "SDW_DP0_INT read failed:%d\n", ret);
             goto io_err;
         }
         sdca_cascade = ret & SDW_DP0_SDCA_CASCADE;
     }
 
     do {
         slave_notify = false;
 
         /*
          * Check parity, bus clash and Slave (impl defined)
          * interrupt
          */
         if (buf & SDW_SCP_INT1_PARITY) {
             parity_check = slave->prop.scp_int1_mask & SDW_SCP_INT1_PARITY;
             parity_quirk = !slave->first_interrupt_done &&
                 (slave->prop.quirks & SDW_SLAVE_QUIRKS_INVALID_INITIAL_PARITY);
 
             if (parity_check && !parity_quirk)
                 dev_err(&slave->dev, "Parity error detected\n");
             clear |= SDW_SCP_INT1_PARITY;
         }
 
         if (buf & SDW_SCP_INT1_BUS_CLASH) {
             if (slave->prop.scp_int1_mask & SDW_SCP_INT1_BUS_CLASH)
                 dev_err(&slave->dev, "Bus clash detected\n");
             clear |= SDW_SCP_INT1_BUS_CLASH;
         }
 
         /*
          * When bus clash or parity errors are detected, such errors
          * are unlikely to be recoverable errors.
          * TODO: In such scenario, reset bus. Make this configurable
          * via sysfs property with bus reset being the default.
          */
 
         if (buf & SDW_SCP_INT1_IMPL_DEF) {
             if (slave->prop.scp_int1_mask & SDW_SCP_INT1_IMPL_DEF) {
                 dev_dbg(&slave->dev, "Slave impl defined interrupt\n");
                 slave_notify = true;
             }
             clear |= SDW_SCP_INT1_IMPL_DEF;
         }
 
         /* the SDCA interrupts are cleared in the codec driver .interrupt_callback() */
         if (sdca_cascade)
             slave_notify = true;
 
         /* Check port 0 - 3 interrupts */
         port = buf & SDW_SCP_INT1_PORT0_3;
 
         /* To get port number corresponding to bits, shift it */
         port = FIELD_GET(SDW_SCP_INT1_PORT0_3, port);
         for_each_set_bit(bit, &port, 8) {
             sdw_handle_port_interrupt(slave, bit,
                           &port_status[bit]);
         }
 
         /* Check if cascade 2 interrupt is present */
         if (buf & SDW_SCP_INT1_SCP2_CASCADE) {
             port = buf2[0] & SDW_SCP_INTSTAT2_PORT4_10;
             for_each_set_bit(bit, &port, 8) {
                 /* scp2 ports start from 4 */
                 port_num = bit + 3;
                 sdw_handle_port_interrupt(slave,
                         port_num,
                         &port_status[port_num]);
             }
         }
 
         /* now check last cascade */
         if (buf2[0] & SDW_SCP_INTSTAT2_SCP3_CASCADE) {
             port = buf2[1] & SDW_SCP_INTSTAT3_PORT11_14;
             for_each_set_bit(bit, &port, 8) {
                 /* scp3 ports start from 11 */
                 port_num = bit + 10;
                 sdw_handle_port_interrupt(slave,
                         port_num,
                         &port_status[port_num]);
             }
         }
 
         /* Update the Slave driver */
         if (slave_notify) {
             mutex_lock(&slave->sdw_dev_lock);
 
             if (slave->probed) {
                 struct device *dev = &slave->dev;
                 struct sdw_driver *drv = drv_to_sdw_driver(dev->driver);
 
                 if (drv->ops && drv->ops->interrupt_callback) {
                     slave_intr.sdca_cascade = sdca_cascade;
                     slave_intr.control_port = clear;
                     memcpy(slave_intr.port, &port_status,
                            sizeof(slave_intr.port));
 
                     drv->ops->interrupt_callback(slave, &slave_intr);
                 }
             }
 
             mutex_unlock(&slave->sdw_dev_lock);
         }
 
         /* Ack interrupt */
         ret = sdw_write_no_pm(slave, SDW_SCP_INT1, clear);
         if (ret < 0) {
             dev_err(&slave->dev,
                 "SDW_SCP_INT1 write failed:%d\n", ret);
             goto io_err;
         }
 
         /* at this point all initial interrupt sources were handled */
         slave->first_interrupt_done = true;
 
         /*
          * Read status again to ensure no new interrupts arrived
          * while servicing interrupts.
          */
         ret = sdw_read_no_pm(slave, SDW_SCP_INT1);
         if (ret < 0) {
             dev_err(&slave->dev,
                 "SDW_SCP_INT1 recheck read failed:%d\n", ret);
             goto io_err;
         }
         _buf = ret;
 
         ret = sdw_nread_no_pm(slave, SDW_SCP_INTSTAT2, 2, _buf2);
         if (ret < 0) {
             dev_err(&slave->dev,
                 "SDW_SCP_INT2/3 recheck read failed:%d\n", ret);
             goto io_err;
         }
 
         if (slave->prop.is_sdca) {
             ret = sdw_read_no_pm(slave, SDW_DP0_INT);
             if (ret < 0) {
                 dev_err(&slave->dev,
                     "SDW_DP0_INT recheck read failed:%d\n", ret);
                 goto io_err;
             }
             sdca_cascade = ret & SDW_DP0_SDCA_CASCADE;
         }
 
         /*
          * Make sure no interrupts are pending, but filter to limit loop
          * to interrupts identified in the first status read
          */
         buf &= _buf;
         buf2[0] &= _buf2[0];
         buf2[1] &= _buf2[1];
         stat = buf || buf2[0] || buf2[1] || sdca_cascade;
 
         /*
          * Exit loop if Slave is continuously in ALERT state even
          * after servicing the interrupt multiple times.
          */
         count++;
 
         /* we can get alerts while processing so keep retrying */
     } while (stat != 0 && count < SDW_READ_INTR_CLEAR_RETRY);
 
     if (count == SDW_READ_INTR_CLEAR_RETRY)
         dev_warn(&slave->dev, "Reached MAX_RETRY on alert read\n");
 
 io_err:
     pm_runtime_mark_last_busy(&slave->dev);
     pm_runtime_put_autosuspend(&slave->dev);
 
     return ret;
 }
 
 static int sdw_update_slave_status(struct sdw_slave *slave,
                    enum sdw_slave_status status)
 {
     int ret = 0;
 
     mutex_lock(&slave->sdw_dev_lock);
 
     if (slave->probed) {
         struct device *dev = &slave->dev;
         struct sdw_driver *drv = drv_to_sdw_driver(dev->driver);
 
         if (drv->ops && drv->ops->update_status)
             ret = drv->ops->update_status(slave, status);
     }
 
     mutex_unlock(&slave->sdw_dev_lock);
 
     return ret;
 }
 
 /**
  * sdw_handle_slave_status() - Handle Slave status
  * @bus: SDW bus instance
  * @status: Status for all Slave(s)
  */
 int sdw_handle_slave_status(struct sdw_bus *bus,
                 enum sdw_slave_status status[])
 {
     enum sdw_slave_status prev_status;
     struct sdw_slave *slave;
     bool attached_initializing;
     int i, ret = 0;
 
     /* first check if any Slaves fell off the bus */
     for (i = 1; i <= SDW_MAX_DEVICES; i++) {
         mutex_lock(&bus->bus_lock);
         if (test_bit(i, bus->assigned) == false) {
             mutex_unlock(&bus->bus_lock);
             continue;
         }
         mutex_unlock(&bus->bus_lock);
 
         slave = sdw_get_slave(bus, i);
         if (!slave)
             continue;
 
         if (status[i] == SDW_SLAVE_UNATTACHED &&
             slave->status != SDW_SLAVE_UNATTACHED) {
             dev_warn(&slave->dev, "Slave %d state check1: UNATTACHED, status was %d\n",
                  i, slave->status);
             sdw_modify_slave_status(slave, SDW_SLAVE_UNATTACHED);
         }
     }
 
     if (status[0] == SDW_SLAVE_ATTACHED) {
         dev_dbg(bus->dev, "Slave attached, programming device number\n");
         ret = sdw_program_device_num(bus);
         if (ret < 0)
             dev_err(bus->dev, "Slave attach failed: %d\n", ret);
         /*
          * programming a device number will have side effects,
          * so we deal with other devices at a later time
          */
         return ret;
     }
 
     /* Continue to check other slave statuses */
     for (i = 1; i <= SDW_MAX_DEVICES; i++) {
         mutex_lock(&bus->bus_lock);
         if (test_bit(i, bus->assigned) == false) {
             mutex_unlock(&bus->bus_lock);
             continue;
         }
         mutex_unlock(&bus->bus_lock);
 
         slave = sdw_get_slave(bus, i);
         if (!slave)
             continue;
 
         attached_initializing = false;
 
         switch (status[i]) {
         case SDW_SLAVE_UNATTACHED:
             if (slave->status == SDW_SLAVE_UNATTACHED)
                 break;
 
             dev_warn(&slave->dev, "Slave %d state check2: UNATTACHED, status was %d\n",
                  i, slave->status);
 
             sdw_modify_slave_status(slave, SDW_SLAVE_UNATTACHED);
             break;
 
         case SDW_SLAVE_ALERT:
             ret = sdw_handle_slave_alerts(slave);
             if (ret < 0)
                 dev_err(&slave->dev,
                     "Slave %d alert handling failed: %d\n",
                     i, ret);
             break;
 
         case SDW_SLAVE_ATTACHED:
             if (slave->status == SDW_SLAVE_ATTACHED)
                 break;
 
             prev_status = slave->status;
             sdw_modify_slave_status(slave, SDW_SLAVE_ATTACHED);
 
             if (prev_status == SDW_SLAVE_ALERT)
                 break;
 
             attached_initializing = true;
 
             ret = sdw_initialize_slave(slave);
             if (ret < 0)
                 dev_err(&slave->dev,
                     "Slave %d initialization failed: %d\n",
                     i, ret);
 
             break;
 
         default:
             dev_err(&slave->dev, "Invalid slave %d status:%d\n",
                 i, status[i]);
             break;
         }
 
         ret = sdw_update_slave_status(slave, status[i]);
         if (ret < 0)
             dev_err(&slave->dev,
                 "Update Slave status failed:%d\n", ret);
         if (attached_initializing) {
             dev_dbg(&slave->dev,
                 "%s: signaling initialization completion for Slave %d\n",
                 __func__, slave->dev_num);
 
             complete(&slave->initialization_complete);
 
             /*
              * If the manager became pm_runtime active, the peripherals will be
              * restarted and attach, but their pm_runtime status may remain
              * suspended. If the 'update_slave_status' callback initiates
              * any sort of deferred processing, this processing would not be
              * cancelled on pm_runtime suspend.
              * To avoid such zombie states, we queue a request to resume.
              * This would be a no-op in case the peripheral was being resumed
              * by e.g. the ALSA/ASoC framework.
              */
             pm_request_resume(&slave->dev);
         }
     }
 
     return ret;
 }
 EXPORT_SYMBOL(sdw_handle_slave_status);
 
 void sdw_clear_slave_status(struct sdw_bus *bus, u32 request)
 {
     struct sdw_slave *slave;
     int i;
 
     /* Check all non-zero devices */
     for (i = 1; i <= SDW_MAX_DEVICES; i++) {
         mutex_lock(&bus->bus_lock);
         if (test_bit(i, bus->assigned) == false) {
             mutex_unlock(&bus->bus_lock);
             continue;
         }
         mutex_unlock(&bus->bus_lock);
 
         slave = sdw_get_slave(bus, i);
         if (!slave)
             continue;
 
         if (slave->status != SDW_SLAVE_UNATTACHED) {
             sdw_modify_slave_status(slave, SDW_SLAVE_UNATTACHED);
             slave->first_interrupt_done = false;
             sdw_update_slave_status(slave, SDW_SLAVE_UNATTACHED);
         }
 
         /* keep track of request, used in pm_runtime resume */
         slave->unattach_request = request;
     }
 }
 EXPORT_SYMBOL(sdw_clear_slave_status);

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