smsc47b397.c

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/*
 * smsc47b397.c - Part of lm_sensors, Linux kernel modules
 * for hardware monitoring
 *
 * Supports the SMSC LPC47B397-NC Super-I/O chip.
 *
 * Author/Maintainer: Mark M. Hoffman <[email protected]>
 * Copyright (C) 2004 Utilitek Systems, Inc.
 *
 * derived in part from smsc47m1.c:
 * Copyright (C) 2002 Mark D. Studebaker <[email protected]>
 * Copyright (C) 2004 Jean Delvare <[email protected]>
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation; either version 2 of the License, or
 * (at your option) any later version.
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program; if not, write to the Free Software
 * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
 */

#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt

#include <linux/module.h>
#include <linux/slab.h>
#include <linux/ioport.h>
#include <linux/jiffies.h>
#include <linux/platform_device.h>
#include <linux/hwmon.h>
#include <linux/hwmon-sysfs.h>
#include <linux/err.h>
#include <linux/init.h>
#include <linux/mutex.h>
#include <linux/acpi.h>
#include <linux/io.h>

static unsigned short force_id;
module_param(force_id, ushort, 0);
MODULE_PARM_DESC(force_id, "Override the detected device ID");

static struct platform_device *pdev;

#define DRVNAME "smsc47b397"

/* Super-I/0 registers and commands */

#define REG 0x2e    /* The register to read/write */
#define VAL 0x2f    /* The value to read/write */

static inline void superio_outb(int reg, int val)
{
    outb(reg, REG);
    outb(val, VAL);
}

static inline int superio_inb(int reg)
{
    outb(reg, REG);
    return inb(VAL);
}

/* select superio logical device */
static inline void superio_select(int ld)
{
    superio_outb(0x07, ld);
}

static inline void superio_enter(void)
{
    outb(0x55, REG);
}

static inline void superio_exit(void)
{
    outb(0xAA, REG);
}

#define SUPERIO_REG_DEVID   0x20
#define SUPERIO_REG_DEVREV  0x21
#define SUPERIO_REG_BASE_MSB    0x60
#define SUPERIO_REG_BASE_LSB    0x61
#define SUPERIO_REG_LD8     0x08

#define SMSC_EXTENT     0x02

/* 0 <= nr <= 3 */
static u8 smsc47b397_reg_temp[] = {0x25, 0x26, 0x27, 0x80};
#define SMSC47B397_REG_TEMP(nr) (smsc47b397_reg_temp[(nr)])

/* 0 <= nr <= 3 */
#define SMSC47B397_REG_FAN_LSB(nr) (0x28 + 2 * (nr))
#define SMSC47B397_REG_FAN_MSB(nr) (0x29 + 2 * (nr))

struct smsc47b397_data {
    unsigned short addr;
    const char *name;
    struct device *hwmon_dev;
    struct mutex lock;

    struct mutex update_lock;
    unsigned long last_updated; /* in jiffies */
    int valid;

    /* register values */
    u16 fan[4];
    u8 temp[4];
};

static int smsc47b397_read_value(struct smsc47b397_data *data, u8 reg)
{
    int res;

    mutex_lock(&data->lock);
    outb(reg, data->addr);
    res = inb_p(data->addr + 1);
    mutex_unlock(&data->lock);
    return res;
}

static struct smsc47b397_data *smsc47b397_update_device(struct device *dev)
{
    struct smsc47b397_data *data = dev_get_drvdata(dev);
    int i;

    mutex_lock(&data->update_lock);

    if (time_after(jiffies, data->last_updated + HZ) || !data->valid) {
        dev_dbg(dev, "starting device update...\n");

        /* 4 temperature inputs, 4 fan inputs */
        for (i = 0; i < 4; i++) {
            data->temp[i] = smsc47b397_read_value(data,
                    SMSC47B397_REG_TEMP(i));

            /* must read LSB first */
            data->fan[i]  = smsc47b397_read_value(data,
                    SMSC47B397_REG_FAN_LSB(i));
            data->fan[i] |= smsc47b397_read_value(data,
                    SMSC47B397_REG_FAN_MSB(i)) << 8;
        }

        data->last_updated = jiffies;
        data->valid = 1;

        dev_dbg(dev, "... device update complete\n");
    }

    mutex_unlock(&data->update_lock);

    return data;
}

/*
 * TEMP: 0.001C/bit (-128C to +127C)
 * REG: 1C/bit, two's complement
 */
static int temp_from_reg(u8 reg)
{
    return (s8)reg * 1000;
}

static ssize_t show_temp(struct device *dev, struct device_attribute
             *devattr, char *buf)
{
    struct sensor_device_attribute *attr = to_sensor_dev_attr(devattr);
    struct smsc47b397_data *data = smsc47b397_update_device(dev);
    return sprintf(buf, "%d\n", temp_from_reg(data->temp[attr->index]));
}

static SENSOR_DEVICE_ATTR(temp1_input, S_IRUGO, show_temp, NULL, 0);
static SENSOR_DEVICE_ATTR(temp2_input, S_IRUGO, show_temp, NULL, 1);
static SENSOR_DEVICE_ATTR(temp3_input, S_IRUGO, show_temp, NULL, 2);
static SENSOR_DEVICE_ATTR(temp4_input, S_IRUGO, show_temp, NULL, 3);

/*
 * FAN: 1 RPM/bit
 * REG: count of 90kHz pulses / revolution
 */
static int fan_from_reg(u16 reg)
{
    if (reg == 0 || reg == 0xffff)
        return 0;
    return 90000 * 60 / reg;
}

static ssize_t show_fan(struct device *dev, struct device_attribute
            *devattr, char *buf)
{
    struct sensor_device_attribute *attr = to_sensor_dev_attr(devattr);
    struct smsc47b397_data *data = smsc47b397_update_device(dev);
    return sprintf(buf, "%d\n", fan_from_reg(data->fan[attr->index]));
}
static SENSOR_DEVICE_ATTR(fan1_input, S_IRUGO, show_fan, NULL, 0);
static SENSOR_DEVICE_ATTR(fan2_input, S_IRUGO, show_fan, NULL, 1);
static SENSOR_DEVICE_ATTR(fan3_input, S_IRUGO, show_fan, NULL, 2);
static SENSOR_DEVICE_ATTR(fan4_input, S_IRUGO, show_fan, NULL, 3);

static ssize_t show_name(struct device *dev, struct device_attribute
             *devattr, char *buf)
{
    struct smsc47b397_data *data = dev_get_drvdata(dev);
    return sprintf(buf, "%s\n", data->name);
}
static DEVICE_ATTR(name, S_IRUGO, show_name, NULL);

static struct attribute *smsc47b397_attributes[] = {
    &sensor_dev_attr_temp1_input.dev_attr.attr,
    &sensor_dev_attr_temp2_input.dev_attr.attr,
    &sensor_dev_attr_temp3_input.dev_attr.attr,
    &sensor_dev_attr_temp4_input.dev_attr.attr,
    &sensor_dev_attr_fan1_input.dev_attr.attr,
    &sensor_dev_attr_fan2_input.dev_attr.attr,
    &sensor_dev_attr_fan3_input.dev_attr.attr,
    &sensor_dev_attr_fan4_input.dev_attr.attr,

    &dev_attr_name.attr,
    NULL
};

static const struct attribute_group smsc47b397_group = {
    .attrs = smsc47b397_attributes,
};

static int __devexit smsc47b397_remove(struct platform_device *pdev)
{
    struct smsc47b397_data *data = platform_get_drvdata(pdev);

    hwmon_device_unregister(data->hwmon_dev);
    sysfs_remove_group(&pdev->dev.kobj, &smsc47b397_group);

    return 0;
}

static int smsc47b397_probe(struct platform_device *pdev);

static struct platform_driver smsc47b397_driver = {
    .driver = {
        .owner  = THIS_MODULE,
        .name   = DRVNAME,
    },
    .probe      = smsc47b397_probe,
    .remove     = __devexit_p(smsc47b397_remove),
};

static int __devinit smsc47b397_probe(struct platform_device *pdev)
{
    struct device *dev = &pdev->dev;
    struct smsc47b397_data *data;
    struct resource *res;
    int err = 0;

    res = platform_get_resource(pdev, IORESOURCE_IO, 0);
    if (!devm_request_region(dev, res->start, SMSC_EXTENT,
                 smsc47b397_driver.driver.name)) {
        dev_err(dev, "Region 0x%lx-0x%lx already in use!\n",
            (unsigned long)res->start,
            (unsigned long)res->start + SMSC_EXTENT - 1);
        return -EBUSY;
    }

    data = devm_kzalloc(dev, sizeof(struct smsc47b397_data), GFP_KERNEL);
    if (!data)
        return -ENOMEM;

    data->addr = res->start;
    data->name = "smsc47b397";
    mutex_init(&data->lock);
    mutex_init(&data->update_lock);
    platform_set_drvdata(pdev, data);

    err = sysfs_create_group(&dev->kobj, &smsc47b397_group);
    if (err)
        return err;

    data->hwmon_dev = hwmon_device_register(dev);
    if (IS_ERR(data->hwmon_dev)) {
        err = PTR_ERR(data->hwmon_dev);
        goto error_remove;
    }

    return 0;

error_remove:
    sysfs_remove_group(&dev->kobj, &smsc47b397_group);
    return err;
}

static int __init smsc47b397_device_add(unsigned short address)
{
    struct resource res = {
        .start  = address,
        .end    = address + SMSC_EXTENT - 1,
        .name   = DRVNAME,
        .flags  = IORESOURCE_IO,
    };
    int err;

    err = acpi_check_resource_conflict(&res);
    if (err)
        goto exit;

    pdev = platform_device_alloc(DRVNAME, address);
    if (!pdev) {
        err = -ENOMEM;
        pr_err("Device allocation failed\n");
        goto exit;
    }

    err = platform_device_add_resources(pdev, &res, 1);
    if (err) {
        pr_err("Device resource addition failed (%d)\n", err);
        goto exit_device_put;
    }

    err = platform_device_add(pdev);
    if (err) {
        pr_err("Device addition failed (%d)\n", err);
        goto exit_device_put;
    }

    return 0;

exit_device_put:
    platform_device_put(pdev);
exit:
    return err;
}

static int __init smsc47b397_find(void)
{
    u8 id, rev;
    char *name;
    unsigned short addr;

    superio_enter();
    id = force_id ? force_id : superio_inb(SUPERIO_REG_DEVID);

    switch (id) {
    case 0x81:
        name = "SCH5307-NS";
        break;
    case 0x6f:
        name = "LPC47B397-NC";
        break;
    case 0x85:
    case 0x8c:
        name = "SCH5317";
        break;
    default:
        superio_exit();
        return -ENODEV;
    }

    rev = superio_inb(SUPERIO_REG_DEVREV);

    superio_select(SUPERIO_REG_LD8);
    addr = (superio_inb(SUPERIO_REG_BASE_MSB) << 8)
         |  superio_inb(SUPERIO_REG_BASE_LSB);

    pr_info("found SMSC %s (base address 0x%04x, revision %u)\n",
        name, addr, rev);

    superio_exit();
    return addr;
}

static int __init smsc47b397_init(void)
{
    unsigned short address;
    int ret;

    ret = smsc47b397_find();
    if (ret < 0)
        return ret;
    address = ret;

    ret = platform_driver_register(&smsc47b397_driver);
    if (ret)
        goto exit;

    /* Sets global pdev as a side effect */
    ret = smsc47b397_device_add(address);
    if (ret)
        goto exit_driver;

    return 0;

exit_driver:
    platform_driver_unregister(&smsc47b397_driver);
exit:
    return ret;
}

static void __exit smsc47b397_exit(void)
{
    platform_device_unregister(pdev);
    platform_driver_unregister(&smsc47b397_driver);
}

MODULE_AUTHOR("Mark M. Hoffman <[email protected]>");
MODULE_DESCRIPTION("SMSC LPC47B397 driver");
MODULE_LICENSE("GPL");

module_init(smsc47b397_init);
module_exit(smsc47b397_exit);