drivers/hwmon/smsc47b397.c

0001 // SPDX-License-Identifier: GPL-2.0-or-later
0002 /*
0003  * smsc47b397.c - Part of lm_sensors, Linux kernel modules
0004  * for hardware monitoring
0005  *
0006  * Supports the SMSC LPC47B397-NC Super-I/O chip.
0007  *
0008  * Author/Maintainer: Mark M. Hoffman <mhoffman@lightlink.com>
0009  * Copyright (C) 2004 Utilitek Systems, Inc.
0010  *
0011  * derived in part from smsc47m1.c:
0012  * Copyright (C) 2002 Mark D. Studebaker <mdsxyz123@yahoo.com>
0013  * Copyright (C) 2004 Jean Delvare <jdelvare@suse.de>
0014  */
0015
0016 #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
0017
0018 #include <linux/module.h>
0019 #include <linux/slab.h>
0020 #include <linux/ioport.h>
0021 #include <linux/jiffies.h>
0022 #include <linux/platform_device.h>
0023 #include <linux/hwmon.h>
0024 #include <linux/hwmon-sysfs.h>
0025 #include <linux/err.h>
0026 #include <linux/init.h>
0027 #include <linux/mutex.h>
0028 #include <linux/acpi.h>
0029 #include <linux/io.h>
0030
0031 static unsigned short force_id;
0032 module_param(force_id, ushort, 0);
0033 MODULE_PARM_DESC(force_id, "Override the detected device ID");
0034
0035 static struct platform_device *pdev;
0036
0037 #define DRVNAME "smsc47b397"
0038
0039 /* Super-I/0 registers and commands */
0040
0041 #define REG 0x2e    /* The register to read/write */
0042 #define VAL 0x2f    /* The value to read/write */
0043
0044 static inline void superio_outb(int reg, int val)
0045 {
0046     outb(reg, REG);
0047     outb(val, VAL);
0048 }
0049
0050 static inline int superio_inb(int reg)
0051 {
0052     outb(reg, REG);
0053     return inb(VAL);
0054 }
0055
0056 /* select superio logical device */
0057 static inline void superio_select(int ld)
0058 {
0059     superio_outb(0x07, ld);
0060 }
0061
0062 static inline int superio_enter(void)
0063 {
0064     if (!request_muxed_region(REG, 2, DRVNAME))
0065         return -EBUSY;
0066
0067     outb(0x55, REG);
0068     return 0;
0069 }
0070
0071 static inline void superio_exit(void)
0072 {
0073     outb(0xAA, REG);
0074     release_region(REG, 2);
0075 }
0076
0077 #define SUPERIO_REG_DEVID   0x20
0078 #define SUPERIO_REG_DEVREV  0x21
0079 #define SUPERIO_REG_BASE_MSB    0x60
0080 #define SUPERIO_REG_BASE_LSB    0x61
0081 #define SUPERIO_REG_LD8     0x08
0082
0083 #define SMSC_EXTENT     0x02
0084
0085 /* 0 <= nr <= 3 */
0086 static u8 smsc47b397_reg_temp[] = {0x25, 0x26, 0x27, 0x80};
0087 #define SMSC47B397_REG_TEMP(nr) (smsc47b397_reg_temp[(nr)])
0088
0089 /* 0 <= nr <= 3 */
0090 #define SMSC47B397_REG_FAN_LSB(nr) (0x28 + 2 * (nr))
0091 #define SMSC47B397_REG_FAN_MSB(nr) (0x29 + 2 * (nr))
0092
0093 struct smsc47b397_data {
0094     unsigned short addr;
0095     struct mutex lock;
0096
0097     struct mutex update_lock;
0098     unsigned long last_updated; /* in jiffies */
0099     bool valid;
0100
0101     /* register values */
0102     u16 fan[4];
0103     u8 temp[4];
0104 };
0105
0106 static int smsc47b397_read_value(struct smsc47b397_data *data, u8 reg)
0107 {
0108     int res;
0109
0110     mutex_lock(&data->lock);
0111     outb(reg, data->addr);
0112     res = inb_p(data->addr + 1);
0113     mutex_unlock(&data->lock);
0114     return res;
0115 }
0116
0117 static struct smsc47b397_data *smsc47b397_update_device(struct device *dev)
0118 {
0119     struct smsc47b397_data *data = dev_get_drvdata(dev);
0120     int i;
0121
0122     mutex_lock(&data->update_lock);
0123
0124     if (time_after(jiffies, data->last_updated + HZ) || !data->valid) {
0125         dev_dbg(dev, "starting device update...\n");
0126
0127         /* 4 temperature inputs, 4 fan inputs */
0128         for (i = 0; i < 4; i++) {
0129             data->temp[i] = smsc47b397_read_value(data,
0130                     SMSC47B397_REG_TEMP(i));
0131
0132             /* must read LSB first */
0133             data->fan[i]  = smsc47b397_read_value(data,
0134                     SMSC47B397_REG_FAN_LSB(i));
0135             data->fan[i] |= smsc47b397_read_value(data,
0136                     SMSC47B397_REG_FAN_MSB(i)) << 8;
0137         }
0138
0139         data->last_updated = jiffies;
0140         data->valid = true;
0141
0142         dev_dbg(dev, "... device update complete\n");
0143     }
0144
0145     mutex_unlock(&data->update_lock);
0146
0147     return data;
0148 }
0149
0150 /*
0151  * TEMP: 0.001C/bit (-128C to +127C)
0152  * REG: 1C/bit, two's complement
0153  */
0154 static int temp_from_reg(u8 reg)
0155 {
0156     return (s8)reg * 1000;
0157 }
0158
0159 static ssize_t temp_show(struct device *dev, struct device_attribute *devattr,
0160              char *buf)
0161 {
0162     struct sensor_device_attribute *attr = to_sensor_dev_attr(devattr);
0163     struct smsc47b397_data *data = smsc47b397_update_device(dev);
0164     return sprintf(buf, "%d\n", temp_from_reg(data->temp[attr->index]));
0165 }
0166
0167 static SENSOR_DEVICE_ATTR_RO(temp1_input, temp, 0);
0168 static SENSOR_DEVICE_ATTR_RO(temp2_input, temp, 1);
0169 static SENSOR_DEVICE_ATTR_RO(temp3_input, temp, 2);
0170 static SENSOR_DEVICE_ATTR_RO(temp4_input, temp, 3);
0171
0172 /*
0173  * FAN: 1 RPM/bit
0174  * REG: count of 90kHz pulses / revolution
0175  */
0176 static int fan_from_reg(u16 reg)
0177 {
0178     if (reg == 0 || reg == 0xffff)
0179         return 0;
0180     return 90000 * 60 / reg;
0181 }
0182
0183 static ssize_t fan_show(struct device *dev, struct device_attribute *devattr,
0184             char *buf)
0185 {
0186     struct sensor_device_attribute *attr = to_sensor_dev_attr(devattr);
0187     struct smsc47b397_data *data = smsc47b397_update_device(dev);
0188     return sprintf(buf, "%d\n", fan_from_reg(data->fan[attr->index]));
0189 }
0190 static SENSOR_DEVICE_ATTR_RO(fan1_input, fan, 0);
0191 static SENSOR_DEVICE_ATTR_RO(fan2_input, fan, 1);
0192 static SENSOR_DEVICE_ATTR_RO(fan3_input, fan, 2);
0193 static SENSOR_DEVICE_ATTR_RO(fan4_input, fan, 3);
0194
0195 static struct attribute *smsc47b397_attrs[] = {
0196     &sensor_dev_attr_temp1_input.dev_attr.attr,
0197     &sensor_dev_attr_temp2_input.dev_attr.attr,
0198     &sensor_dev_attr_temp3_input.dev_attr.attr,
0199     &sensor_dev_attr_temp4_input.dev_attr.attr,
0200     &sensor_dev_attr_fan1_input.dev_attr.attr,
0201     &sensor_dev_attr_fan2_input.dev_attr.attr,
0202     &sensor_dev_attr_fan3_input.dev_attr.attr,
0203     &sensor_dev_attr_fan4_input.dev_attr.attr,
0204
0205     NULL
0206 };
0207
0208 ATTRIBUTE_GROUPS(smsc47b397);
0209
0210 static int smsc47b397_probe(struct platform_device *pdev);
0211
0212 static struct platform_driver smsc47b397_driver = {
0213     .driver = {
0214         .name   = DRVNAME,
0215     },
0216     .probe      = smsc47b397_probe,
0217 };
0218
0219 static int smsc47b397_probe(struct platform_device *pdev)
0220 {
0221     struct device *dev = &pdev->dev;
0222     struct smsc47b397_data *data;
0223     struct device *hwmon_dev;
0224     struct resource *res;
0225
0226     res = platform_get_resource(pdev, IORESOURCE_IO, 0);
0227     if (!devm_request_region(dev, res->start, SMSC_EXTENT,
0228                  smsc47b397_driver.driver.name)) {
0229         dev_err(dev, "Region 0x%lx-0x%lx already in use!\n",
0230             (unsigned long)res->start,
0231             (unsigned long)res->start + SMSC_EXTENT - 1);
0232         return -EBUSY;
0233     }
0234
0235     data = devm_kzalloc(dev, sizeof(struct smsc47b397_data), GFP_KERNEL);
0236     if (!data)
0237         return -ENOMEM;
0238
0239     data->addr = res->start;
0240     mutex_init(&data->lock);
0241     mutex_init(&data->update_lock);
0242
0243     hwmon_dev = devm_hwmon_device_register_with_groups(dev, "smsc47b397",
0244                                data,
0245                                smsc47b397_groups);
0246     return PTR_ERR_OR_ZERO(hwmon_dev);
0247 }
0248
0249 static int __init smsc47b397_device_add(unsigned short address)
0250 {
0251     struct resource res = {
0252         .start  = address,
0253         .end    = address + SMSC_EXTENT - 1,
0254         .name   = DRVNAME,
0255         .flags  = IORESOURCE_IO,
0256     };
0257     int err;
0258
0259     err = acpi_check_resource_conflict(&res);
0260     if (err)
0261         goto exit;
0262
0263     pdev = platform_device_alloc(DRVNAME, address);
0264     if (!pdev) {
0265         err = -ENOMEM;
0266         pr_err("Device allocation failed\n");
0267         goto exit;
0268     }
0269
0270     err = platform_device_add_resources(pdev, &res, 1);
0271     if (err) {
0272         pr_err("Device resource addition failed (%d)\n", err);
0273         goto exit_device_put;
0274     }
0275
0276     err = platform_device_add(pdev);
0277     if (err) {
0278         pr_err("Device addition failed (%d)\n", err);
0279         goto exit_device_put;
0280     }
0281
0282     return 0;
0283
0284 exit_device_put:
0285     platform_device_put(pdev);
0286 exit:
0287     return err;
0288 }
0289
0290 static int __init smsc47b397_find(void)
0291 {
0292     u8 id, rev;
0293     char *name;
0294     unsigned short addr;
0295     int err;
0296
0297     err = superio_enter();
0298     if (err)
0299         return err;
0300
0301     id = force_id ? force_id : superio_inb(SUPERIO_REG_DEVID);
0302
0303     switch (id) {
0304     case 0x81:
0305         name = "SCH5307-NS";
0306         break;
0307     case 0x6f:
0308         name = "LPC47B397-NC";
0309         break;
0310     case 0x85:
0311     case 0x8c:
0312         name = "SCH5317";
0313         break;
0314     default:
0315         superio_exit();
0316         return -ENODEV;
0317     }
0318
0319     rev = superio_inb(SUPERIO_REG_DEVREV);
0320
0321     superio_select(SUPERIO_REG_LD8);
0322     addr = (superio_inb(SUPERIO_REG_BASE_MSB) << 8)
0323          |  superio_inb(SUPERIO_REG_BASE_LSB);
0324
0325     pr_info("found SMSC %s (base address 0x%04x, revision %u)\n",
0326         name, addr, rev);
0327
0328     superio_exit();
0329     return addr;
0330 }
0331
0332 static int __init smsc47b397_init(void)
0333 {
0334     unsigned short address;
0335     int ret;
0336
0337     ret = smsc47b397_find();
0338     if (ret < 0)
0339         return ret;
0340     address = ret;
0341
0342     ret = platform_driver_register(&smsc47b397_driver);
0343     if (ret)
0344         goto exit;
0345
0346     /* Sets global pdev as a side effect */
0347     ret = smsc47b397_device_add(address);
0348     if (ret)
0349         goto exit_driver;
0350
0351     return 0;
0352
0353 exit_driver:
0354     platform_driver_unregister(&smsc47b397_driver);
0355 exit:
0356     return ret;
0357 }
0358
0359 static void __exit smsc47b397_exit(void)
0360 {
0361     platform_device_unregister(pdev);
0362     platform_driver_unregister(&smsc47b397_driver);
0363 }
0364
0365 MODULE_AUTHOR("Mark M. Hoffman <mhoffman@lightlink.com>");
0366 MODULE_DESCRIPTION("SMSC LPC47B397 driver");
0367 MODULE_LICENSE("GPL");
0368
0369 module_init(smsc47b397_init);
0370 module_exit(smsc47b397_exit);