wm8739.c

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/*
 * wm8739
 *
 * Copyright (C) 2005 T. Adachi <[email protected]>
 *
 * Copyright (C) 2005 Hans Verkuil <[email protected]>
 * - Cleanup
 *
 * 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.
 */

#include <linux/module.h>
#include <linux/types.h>
#include <linux/slab.h>
#include <linux/ioctl.h>
#include <asm/uaccess.h>
#include <linux/i2c.h>
#include <linux/videodev2.h>
#include <media/v4l2-device.h>
#include <media/v4l2-chip-ident.h>
#include <media/v4l2-ctrls.h>

MODULE_DESCRIPTION("wm8739 driver");
MODULE_AUTHOR("T. Adachi, Hans Verkuil");
MODULE_LICENSE("GPL");

static int debug;

module_param(debug, int, 0644);

MODULE_PARM_DESC(debug, "Debug level (0-1)");


/* ------------------------------------------------------------------------ */

enum {
    R0 = 0, R1,
    R5 = 5, R6, R7, R8, R9, R15 = 15,
    TOT_REGS
};

struct wm8739_state {
    struct v4l2_subdev sd;
    struct v4l2_ctrl_handler hdl;
    struct {
        /* audio cluster */
        struct v4l2_ctrl *volume;
        struct v4l2_ctrl *mute;
        struct v4l2_ctrl *balance;
    };
    u32 clock_freq;
};

static inline struct wm8739_state *to_state(struct v4l2_subdev *sd)
{
    return container_of(sd, struct wm8739_state, sd);
}

static inline struct v4l2_subdev *to_sd(struct v4l2_ctrl *ctrl)
{
    return &container_of(ctrl->handler, struct wm8739_state, hdl)->sd;
}

/* ------------------------------------------------------------------------ */

static int wm8739_write(struct v4l2_subdev *sd, int reg, u16 val)
{
    struct i2c_client *client = v4l2_get_subdevdata(sd);
    int i;

    if (reg < 0 || reg >= TOT_REGS) {
        v4l2_err(sd, "Invalid register R%d\n", reg);
        return -1;
    }

    v4l2_dbg(1, debug, sd, "write: %02x %02x\n", reg, val);

    for (i = 0; i < 3; i++)
        if (i2c_smbus_write_byte_data(client,
                (reg << 1) | (val >> 8), val & 0xff) == 0)
            return 0;
    v4l2_err(sd, "I2C: cannot write %03x to register R%d\n", val, reg);
    return -1;
}

static int wm8739_s_ctrl(struct v4l2_ctrl *ctrl)
{
    struct v4l2_subdev *sd = to_sd(ctrl);
    struct wm8739_state *state = to_state(sd);
    unsigned int work_l, work_r;
    u8 vol_l;   /* +12dB to -34.5dB 1.5dB step (5bit) def:0dB */
    u8 vol_r;   /* +12dB to -34.5dB 1.5dB step (5bit) def:0dB */
    u16 mute;

    switch (ctrl->id) {
    case V4L2_CID_AUDIO_VOLUME:
        break;

    default:
        return -EINVAL;
    }

    /* normalize ( 65535 to 0 -> 31 to 0 (12dB to -34.5dB) ) */
    work_l = (min(65536 - state->balance->val, 32768) * state->volume->val) / 32768;
    work_r = (min(state->balance->val, 32768) * state->volume->val) / 32768;

    vol_l = (long)work_l * 31 / 65535;
    vol_r = (long)work_r * 31 / 65535;

    /* set audio volume etc. */
    mute = state->mute->val ? 0x80 : 0;

    /* Volume setting: bits 0-4, 0x1f = 12 dB, 0x00 = -34.5 dB
     * Default setting: 0x17 = 0 dB
     */
    wm8739_write(sd, R0, (vol_l & 0x1f) | mute);
    wm8739_write(sd, R1, (vol_r & 0x1f) | mute);
    return 0;
}

/* ------------------------------------------------------------------------ */

static int wm8739_s_clock_freq(struct v4l2_subdev *sd, u32 audiofreq)
{
    struct wm8739_state *state = to_state(sd);

    state->clock_freq = audiofreq;
    /* de-activate */
    wm8739_write(sd, R9, 0x000);
    switch (audiofreq) {
    case 44100:
        /* 256fps, fs=44.1k */
        wm8739_write(sd, R8, 0x020);
        break;
    case 48000:
        /* 256fps, fs=48k */
        wm8739_write(sd, R8, 0x000);
        break;
    case 32000:
        /* 256fps, fs=32k */
        wm8739_write(sd, R8, 0x018);
        break;
    default:
        break;
    }
    /* activate */
    wm8739_write(sd, R9, 0x001);
    return 0;
}

static int wm8739_g_chip_ident(struct v4l2_subdev *sd, struct v4l2_dbg_chip_ident *chip)
{
    struct i2c_client *client = v4l2_get_subdevdata(sd);

    return v4l2_chip_ident_i2c_client(client, chip, V4L2_IDENT_WM8739, 0);
}

static int wm8739_log_status(struct v4l2_subdev *sd)
{
    struct wm8739_state *state = to_state(sd);

    v4l2_info(sd, "Frequency: %u Hz\n", state->clock_freq);
    v4l2_ctrl_handler_log_status(&state->hdl, sd->name);
    return 0;
}

/* ----------------------------------------------------------------------- */

static const struct v4l2_ctrl_ops wm8739_ctrl_ops = {
    .s_ctrl = wm8739_s_ctrl,
};

static const struct v4l2_subdev_core_ops wm8739_core_ops = {
    .log_status = wm8739_log_status,
    .g_chip_ident = wm8739_g_chip_ident,
    .g_ext_ctrls = v4l2_subdev_g_ext_ctrls,
    .try_ext_ctrls = v4l2_subdev_try_ext_ctrls,
    .s_ext_ctrls = v4l2_subdev_s_ext_ctrls,
    .g_ctrl = v4l2_subdev_g_ctrl,
    .s_ctrl = v4l2_subdev_s_ctrl,
    .queryctrl = v4l2_subdev_queryctrl,
    .querymenu = v4l2_subdev_querymenu,
};

static const struct v4l2_subdev_audio_ops wm8739_audio_ops = {
    .s_clock_freq = wm8739_s_clock_freq,
};

static const struct v4l2_subdev_ops wm8739_ops = {
    .core = &wm8739_core_ops,
    .audio = &wm8739_audio_ops,
};

/* ------------------------------------------------------------------------ */

/* i2c implementation */

static int wm8739_probe(struct i2c_client *client,
            const struct i2c_device_id *id)
{
    struct wm8739_state *state;
    struct v4l2_subdev *sd;

    /* Check if the adapter supports the needed features */
    if (!i2c_check_functionality(client->adapter, I2C_FUNC_SMBUS_BYTE_DATA))
        return -EIO;

    v4l_info(client, "chip found @ 0x%x (%s)\n",
            client->addr << 1, client->adapter->name);

    state = kzalloc(sizeof(struct wm8739_state), GFP_KERNEL);
    if (state == NULL)
        return -ENOMEM;
    sd = &state->sd;
    v4l2_i2c_subdev_init(sd, client, &wm8739_ops);
    v4l2_ctrl_handler_init(&state->hdl, 2);
    state->volume = v4l2_ctrl_new_std(&state->hdl, &wm8739_ctrl_ops,
            V4L2_CID_AUDIO_VOLUME, 0, 65535, 65535 / 100, 50736);
    state->mute = v4l2_ctrl_new_std(&state->hdl, &wm8739_ctrl_ops,
            V4L2_CID_AUDIO_MUTE, 0, 1, 1, 0);
    state->balance = v4l2_ctrl_new_std(&state->hdl, &wm8739_ctrl_ops,
            V4L2_CID_AUDIO_BALANCE, 0, 65535, 65535 / 100, 32768);
    sd->ctrl_handler = &state->hdl;
    if (state->hdl.error) {
        int err = state->hdl.error;

        v4l2_ctrl_handler_free(&state->hdl);
        kfree(state);
        return err;
    }
    v4l2_ctrl_cluster(3, &state->volume);

    state->clock_freq = 48000;

    /* Initialize wm8739 */

    /* reset */
    wm8739_write(sd, R15, 0x00);
    /* filter setting, high path, offet clear */
    wm8739_write(sd, R5, 0x000);
    /* ADC, OSC, Power Off mode Disable */
    wm8739_write(sd, R6, 0x000);
    /* Digital Audio interface format:
       Enable Master mode, 24 bit, MSB first/left justified */
    wm8739_write(sd, R7, 0x049);
    /* sampling control: normal, 256fs, 48KHz sampling rate */
    wm8739_write(sd, R8, 0x000);
    /* activate */
    wm8739_write(sd, R9, 0x001);
    /* set volume/mute */
    v4l2_ctrl_handler_setup(&state->hdl);
    return 0;
}

static int wm8739_remove(struct i2c_client *client)
{
    struct v4l2_subdev *sd = i2c_get_clientdata(client);
    struct wm8739_state *state = to_state(sd);

    v4l2_device_unregister_subdev(sd);
    v4l2_ctrl_handler_free(&state->hdl);
    kfree(to_state(sd));
    return 0;
}

static const struct i2c_device_id wm8739_id[] = {
    { "wm8739", 0 },
    { }
};
MODULE_DEVICE_TABLE(i2c, wm8739_id);

static struct i2c_driver wm8739_driver = {
    .driver = {
        .owner  = THIS_MODULE,
        .name   = "wm8739",
    },
    .probe      = wm8739_probe,
    .remove     = wm8739_remove,
    .id_table   = wm8739_id,
};

module_i2c_driver(wm8739_driver);