apanel.c

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/*
 *  Fujitsu Lifebook Application Panel button drive
 *
 *  Copyright (C) 2007 Stephen Hemminger <[email protected]>
 *  Copyright (C) 2001-2003 Jochen Eisinger <[email protected]>
 *
 * This program is free software; you can redistribute it and/or modify it
 * under the terms of the GNU General Public License version 2 as published by
 * the Free Software Foundation.
 *
 * Many Fujitsu Lifebook laptops have a small panel of buttons that are
 * accessible via the i2c/smbus interface. This driver polls those
 * buttons and generates input events.
 *
 * For more details see:
 *  http://apanel.sourceforge.net/tech.php
 */

#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/ioport.h>
#include <linux/io.h>
#include <linux/input-polldev.h>
#include <linux/i2c.h>
#include <linux/workqueue.h>
#include <linux/leds.h>

#define APANEL_NAME "Fujitsu Application Panel"
#define APANEL_VERSION  "1.3.1"
#define APANEL      "apanel"

/* How often we poll keys - msecs */
#define POLL_INTERVAL_DEFAULT   1000

/* Magic constants in BIOS that tell about buttons */
enum apanel_devid {
    APANEL_DEV_NONE   = 0,
    APANEL_DEV_APPBTN = 1,
    APANEL_DEV_CDBTN  = 2,
    APANEL_DEV_LCD    = 3,
    APANEL_DEV_LED    = 4,

    APANEL_DEV_MAX,
};

enum apanel_chip {
    CHIP_NONE    = 0,
    CHIP_OZ992C  = 1,
    CHIP_OZ163T  = 2,
    CHIP_OZ711M3 = 4,
};

/* Result of BIOS snooping/probing -- what features are supported */
static enum apanel_chip device_chip[APANEL_DEV_MAX];

#define MAX_PANEL_KEYS  12

struct apanel {
    struct input_polled_dev *ipdev;
    struct i2c_client *client;
    unsigned short keymap[MAX_PANEL_KEYS];
    u16    nkeys;
    u16    led_bits;
    struct work_struct led_work;
    struct led_classdev mail_led;
};


static int apanel_probe(struct i2c_client *, const struct i2c_device_id *);

static void report_key(struct input_dev *input, unsigned keycode)
{
    pr_debug(APANEL ": report key %#x\n", keycode);
    input_report_key(input, keycode, 1);
    input_sync(input);

    input_report_key(input, keycode, 0);
    input_sync(input);
}

/* Poll for key changes
 *
 * Read Application keys via SMI
 *  A (0x4), B (0x8), Internet (0x2), Email (0x1).
 *
 * CD keys:
 * Forward (0x100), Rewind (0x200), Stop (0x400), Pause (0x800)
 */
static void apanel_poll(struct input_polled_dev *ipdev)
{
    struct apanel *ap = ipdev->private;
    struct input_dev *idev = ipdev->input;
    u8 cmd = device_chip[APANEL_DEV_APPBTN] == CHIP_OZ992C ? 0 : 8;
    s32 data;
    int i;

    data = i2c_smbus_read_word_data(ap->client, cmd);
    if (data < 0)
        return; /* ignore errors (due to ACPI??) */

    /* write back to clear latch */
    i2c_smbus_write_word_data(ap->client, cmd, 0);

    if (!data)
        return;

    dev_dbg(&idev->dev, APANEL ": data %#x\n", data);
    for (i = 0; i < idev->keycodemax; i++)
        if ((1u << i) & data)
            report_key(idev, ap->keymap[i]);
}

/* Track state changes of LED */
static void led_update(struct work_struct *work)
{
    struct apanel *ap = container_of(work, struct apanel, led_work);

    i2c_smbus_write_word_data(ap->client, 0x10, ap->led_bits);
}

static void mail_led_set(struct led_classdev *led,
             enum led_brightness value)
{
    struct apanel *ap = container_of(led, struct apanel, mail_led);

    if (value != LED_OFF)
        ap->led_bits |= 0x8000;
    else
        ap->led_bits &= ~0x8000;

    schedule_work(&ap->led_work);
}

static int apanel_remove(struct i2c_client *client)
{
    struct apanel *ap = i2c_get_clientdata(client);

    if (device_chip[APANEL_DEV_LED] != CHIP_NONE)
        led_classdev_unregister(&ap->mail_led);

    input_unregister_polled_device(ap->ipdev);
    input_free_polled_device(ap->ipdev);

    return 0;
}

static void apanel_shutdown(struct i2c_client *client)
{
    apanel_remove(client);
}

static const struct i2c_device_id apanel_id[] = {
    { "fujitsu_apanel", 0 },
    { }
};
MODULE_DEVICE_TABLE(i2c, apanel_id);

static struct i2c_driver apanel_driver = {
    .driver = {
        .name = APANEL,
    },
    .probe      = &apanel_probe,
    .remove     = &apanel_remove,
    .shutdown   = &apanel_shutdown,
    .id_table   = apanel_id,
};

static struct apanel apanel = {
    .keymap = {
        [0] = KEY_MAIL,
        [1] = KEY_WWW,
        [2] = KEY_PROG2,
        [3] = KEY_PROG1,

        [8] = KEY_FORWARD,
        [9] = KEY_REWIND,
        [10] = KEY_STOPCD,
        [11] = KEY_PLAYPAUSE,

    },
    .mail_led = {
        .name = "mail:blue",
        .brightness_set = mail_led_set,
    },
};

/* NB: Only one panel on the i2c. */
static int apanel_probe(struct i2c_client *client,
            const struct i2c_device_id *id)
{
    struct apanel *ap;
    struct input_polled_dev *ipdev;
    struct input_dev *idev;
    u8 cmd = device_chip[APANEL_DEV_APPBTN] == CHIP_OZ992C ? 0 : 8;
    int i, err = -ENOMEM;

    ap = &apanel;

    ipdev = input_allocate_polled_device();
    if (!ipdev)
        goto out1;

    ap->ipdev = ipdev;
    ap->client = client;

    i2c_set_clientdata(client, ap);

    err = i2c_smbus_write_word_data(client, cmd, 0);
    if (err) {
        dev_warn(&client->dev, APANEL ": smbus write error %d\n",
             err);
        goto out3;
    }

    ipdev->poll = apanel_poll;
    ipdev->poll_interval = POLL_INTERVAL_DEFAULT;
    ipdev->private = ap;

    idev = ipdev->input;
    idev->name = APANEL_NAME " buttons";
    idev->phys = "apanel/input0";
    idev->id.bustype = BUS_HOST;
    idev->dev.parent = &client->dev;

    set_bit(EV_KEY, idev->evbit);

    idev->keycode = ap->keymap;
    idev->keycodesize = sizeof(ap->keymap[0]);
    idev->keycodemax = (device_chip[APANEL_DEV_CDBTN] != CHIP_NONE) ? 12 : 4;

    for (i = 0; i < idev->keycodemax; i++)
        if (ap->keymap[i])
            set_bit(ap->keymap[i], idev->keybit);

    err = input_register_polled_device(ipdev);
    if (err)
        goto out3;

    INIT_WORK(&ap->led_work, led_update);
    if (device_chip[APANEL_DEV_LED] != CHIP_NONE) {
        err = led_classdev_register(&client->dev, &ap->mail_led);
        if (err)
            goto out4;
    }

    return 0;
out4:
    input_unregister_polled_device(ipdev);
out3:
    input_free_polled_device(ipdev);
out1:
    return err;
}

/* Scan the system ROM for the signature "FJKEYINF" */
static __init const void __iomem *bios_signature(const void __iomem *bios)
{
    ssize_t offset;
    const unsigned char signature[] = "FJKEYINF";

    for (offset = 0; offset < 0x10000; offset += 0x10) {
        if (check_signature(bios + offset, signature,
                    sizeof(signature)-1))
            return bios + offset;
    }
    pr_notice(APANEL ": Fujitsu BIOS signature '%s' not found...\n",
          signature);
    return NULL;
}

static int __init apanel_init(void)
{
    void __iomem *bios;
    const void __iomem *p;
    u8 devno;
    unsigned char i2c_addr;
    int found = 0;

    bios = ioremap(0xF0000, 0x10000); /* Can't fail */

    p = bios_signature(bios);
    if (!p) {
        iounmap(bios);
        return -ENODEV;
    }

    /* just use the first address */
    p += 8;
    i2c_addr = readb(p + 3) >> 1;

    for ( ; (devno = readb(p)) & 0x7f; p += 4) {
        unsigned char method, slave, chip;

        method = readb(p + 1);
        chip = readb(p + 2);
        slave = readb(p + 3) >> 1;

        if (slave != i2c_addr) {
            pr_notice(APANEL ": only one SMBus slave "
                  "address supported, skiping device...\n");
            continue;
        }

        /* translate alternative device numbers */
        switch (devno) {
        case 6:
            devno = APANEL_DEV_APPBTN;
            break;
        case 7:
            devno = APANEL_DEV_LED;
            break;
        }

        if (devno >= APANEL_DEV_MAX)
            pr_notice(APANEL ": unknown device %u found\n", devno);
        else if (device_chip[devno] != CHIP_NONE)
            pr_warning(APANEL ": duplicate entry for devno %u\n", devno);

        else if (method != 1 && method != 2 && method != 4) {
            pr_notice(APANEL ": unknown method %u for devno %u\n",
                  method, devno);
        } else {
            device_chip[devno] = (enum apanel_chip) chip;
            ++found;
        }
    }
    iounmap(bios);

    if (found == 0) {
        pr_info(APANEL ": no input devices reported by BIOS\n");
        return -EIO;
    }

    return i2c_add_driver(&apanel_driver);
}
module_init(apanel_init);

static void __exit apanel_cleanup(void)
{
    i2c_del_driver(&apanel_driver);
}
module_exit(apanel_cleanup);

MODULE_AUTHOR("Stephen Hemminger <[email protected]>");
MODULE_DESCRIPTION(APANEL_NAME " driver");
MODULE_LICENSE("GPL");
MODULE_VERSION(APANEL_VERSION);

MODULE_ALIAS("dmi:*:svnFUJITSU:pnLifeBook*:pvr*:rvnFUJITSU:*");
MODULE_ALIAS("dmi:*:svnFUJITSU:pnLifebook*:pvr*:rvnFUJITSU:*");