bf5xx-ac97.c

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/*
 * bf5xx-ac97.c -- AC97 support for the ADI blackfin chip.
 *
 * Author:  Roy Huang
 * Created: 11th. June 2007
 * Copyright:   Analog Device Inc.
 *
 * 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.
 */

#include <linux/init.h>
#include <linux/module.h>
#include <linux/platform_device.h>
#include <linux/interrupt.h>
#include <linux/wait.h>
#include <linux/delay.h>
#include <linux/slab.h>

#include <sound/core.h>
#include <sound/pcm.h>
#include <sound/ac97_codec.h>
#include <sound/initval.h>
#include <sound/soc.h>

#include <asm/irq.h>
#include <asm/portmux.h>
#include <linux/mutex.h>
#include <linux/gpio.h>

#include "bf5xx-sport.h"
#include "bf5xx-ac97.h"

/* Anomaly notes:
 *  05000250 -  AD1980 is running in TDM mode and RFS/TFS are generated by SPORT
 *      contrtoller. But, RFSDIV and TFSDIV are always set to 16*16-1,
 *      while the max AC97 data size is 13*16. The DIV is always larger
 *      than data size. AD73311 and ad2602 are not running in TDM mode.
 *      AD1836 and AD73322 depend on external RFS/TFS only. So, this
 *      anomaly does not affect blackfin sound drivers.
*/

static struct sport_device *ac97_sport_handle;

void bf5xx_pcm_to_ac97(struct ac97_frame *dst, const __u16 *src,
        size_t count, unsigned int chan_mask)
{
    while (count--) {
        dst->ac97_tag = TAG_VALID;
        if (chan_mask & SP_FL) {
            dst->ac97_pcm_r = *src++;
            dst->ac97_tag |= TAG_PCM_RIGHT;
        }
        if (chan_mask & SP_FR) {
            dst->ac97_pcm_l = *src++;
            dst->ac97_tag |= TAG_PCM_LEFT;

        }
#if defined(CONFIG_SND_BF5XX_MULTICHAN_SUPPORT)
        if (chan_mask & SP_SR) {
            dst->ac97_sl = *src++;
            dst->ac97_tag |= TAG_PCM_SL;
        }
        if (chan_mask & SP_SL) {
            dst->ac97_sr = *src++;
            dst->ac97_tag |= TAG_PCM_SR;
        }
        if (chan_mask & SP_LFE) {
            dst->ac97_lfe = *src++;
            dst->ac97_tag |= TAG_PCM_LFE;
        }
        if (chan_mask & SP_FC) {
            dst->ac97_center = *src++;
            dst->ac97_tag |= TAG_PCM_CENTER;
        }
#endif
        dst++;
    }
}
EXPORT_SYMBOL(bf5xx_pcm_to_ac97);

void bf5xx_ac97_to_pcm(const struct ac97_frame *src, __u16 *dst,
        size_t count)
{
    while (count--) {
        *(dst++) = src->ac97_pcm_l;
        *(dst++) = src->ac97_pcm_r;
        src++;
    }
}
EXPORT_SYMBOL(bf5xx_ac97_to_pcm);

static unsigned int sport_tx_curr_frag(struct sport_device *sport)
{
    return sport->tx_curr_frag = sport_curr_offset_tx(sport) /
            sport->tx_fragsize;
}

static void enqueue_cmd(struct snd_ac97 *ac97, __u16 addr, __u16 data)
{
    struct sport_device *sport = ac97_sport_handle;
    int *cmd_count = sport->private_data;
    int nextfrag = sport_tx_curr_frag(sport);
    struct ac97_frame *nextwrite;

    sport_incfrag(sport, &nextfrag, 1);

    nextwrite = (struct ac97_frame *)(sport->tx_buf +
            nextfrag * sport->tx_fragsize);
    pr_debug("sport->tx_buf:%p, nextfrag:0x%x nextwrite:%p, cmd_count:%d\n",
        sport->tx_buf, nextfrag, nextwrite, cmd_count[nextfrag]);
    nextwrite[cmd_count[nextfrag]].ac97_tag |= TAG_CMD;
    nextwrite[cmd_count[nextfrag]].ac97_addr = addr;
    nextwrite[cmd_count[nextfrag]].ac97_data = data;
    ++cmd_count[nextfrag];
    pr_debug("ac97_sport: Inserting %02x/%04x into fragment %d\n",
            addr >> 8, data, nextfrag);
}

static unsigned short bf5xx_ac97_read(struct snd_ac97 *ac97,
    unsigned short reg)
{
    struct sport_device *sport_handle = ac97_sport_handle;
    struct ac97_frame out_frame[2], in_frame[2];

    pr_debug("%s enter 0x%x\n", __func__, reg);

    /* When dma descriptor is enabled, the register should not be read */
    if (sport_handle->tx_run || sport_handle->rx_run) {
        pr_err("Could you send a mail to [email protected] "
                "to report this?\n");
        return -EFAULT;
    }

    memset(&out_frame, 0, 2 * sizeof(struct ac97_frame));
    memset(&in_frame, 0, 2 * sizeof(struct ac97_frame));
    out_frame[0].ac97_tag = TAG_VALID | TAG_CMD;
    out_frame[0].ac97_addr = ((reg << 8) | 0x8000);
    sport_send_and_recv(sport_handle, (unsigned char *)&out_frame,
            (unsigned char *)&in_frame,
            2 * sizeof(struct ac97_frame));
    return in_frame[1].ac97_data;
}

void bf5xx_ac97_write(struct snd_ac97 *ac97, unsigned short reg,
    unsigned short val)
{
    struct sport_device *sport_handle = ac97_sport_handle;

    pr_debug("%s enter 0x%x:0x%04x\n", __func__, reg, val);

    if (sport_handle->tx_run) {
        enqueue_cmd(ac97, (reg << 8), val); /* write */
        enqueue_cmd(ac97, (reg << 8) | 0x8000, 0); /* read back */
    } else {
        struct ac97_frame frame;
        memset(&frame, 0, sizeof(struct ac97_frame));
        frame.ac97_tag = TAG_VALID | TAG_CMD;
        frame.ac97_addr = (reg << 8);
        frame.ac97_data = val;
        sport_send_and_recv(sport_handle, (unsigned char *)&frame, \
                NULL, sizeof(struct ac97_frame));
    }
}

static void bf5xx_ac97_warm_reset(struct snd_ac97 *ac97)
{
    struct sport_device *sport_handle = ac97_sport_handle;
    u16 gpio = P_IDENT(sport_handle->pin_req[3]);

    pr_debug("%s enter\n", __func__);

    peripheral_free_list(sport_handle->pin_req);
    gpio_request(gpio, "bf5xx-ac97");
    gpio_direction_output(gpio, 1);
    udelay(2);
    gpio_set_value(gpio, 0);
    udelay(1);
    gpio_free(gpio);
    peripheral_request_list(sport_handle->pin_req, "soc-audio");
}

static void bf5xx_ac97_cold_reset(struct snd_ac97 *ac97)
{
#ifdef CONFIG_SND_BF5XX_HAVE_COLD_RESET
    pr_debug("%s enter\n", __func__);

    /* It is specified for bf548-ezkit */
    gpio_set_value(CONFIG_SND_BF5XX_RESET_GPIO_NUM, 0);
    /* Keep reset pin low for 1 ms */
    mdelay(1);
    gpio_set_value(CONFIG_SND_BF5XX_RESET_GPIO_NUM, 1);
    /* Wait for bit clock recover */
    mdelay(1);
#else
    pr_info("%s: Not implemented\n", __func__);
#endif
}

struct snd_ac97_bus_ops soc_ac97_ops = {
    .read   = bf5xx_ac97_read,
    .write  = bf5xx_ac97_write,
    .warm_reset = bf5xx_ac97_warm_reset,
    .reset  = bf5xx_ac97_cold_reset,
};
EXPORT_SYMBOL_GPL(soc_ac97_ops);

#ifdef CONFIG_PM
static int bf5xx_ac97_suspend(struct snd_soc_dai *dai)
{
    struct sport_device *sport = snd_soc_dai_get_drvdata(dai);

    pr_debug("%s : sport %d\n", __func__, dai->id);
    if (!dai->active)
        return 0;
    if (dai->capture_active)
        sport_rx_stop(sport);
    if (dai->playback_active)
        sport_tx_stop(sport);
    return 0;
}

static int bf5xx_ac97_resume(struct snd_soc_dai *dai)
{
    int ret;
    struct sport_device *sport = snd_soc_dai_get_drvdata(dai);

    pr_debug("%s : sport %d\n", __func__, dai->id);
    if (!dai->active)
        return 0;

#if defined(CONFIG_SND_BF5XX_MULTICHAN_SUPPORT)
    ret = sport_set_multichannel(sport, 16, 0x3FF, 1);
#else
    ret = sport_set_multichannel(sport, 16, 0x1F, 1);
#endif
    if (ret) {
        pr_err("SPORT is busy!\n");
        return -EBUSY;
    }

    ret = sport_config_rx(sport, IRFS, 0xF, 0, (16*16-1));
    if (ret) {
        pr_err("SPORT is busy!\n");
        return -EBUSY;
    }

    ret = sport_config_tx(sport, ITFS, 0xF, 0, (16*16-1));
    if (ret) {
        pr_err("SPORT is busy!\n");
        return -EBUSY;
    }

    return 0;
}

#else
#define bf5xx_ac97_suspend  NULL
#define bf5xx_ac97_resume   NULL
#endif

static struct snd_soc_dai_driver bfin_ac97_dai = {
    .ac97_control = 1,
    .suspend = bf5xx_ac97_suspend,
    .resume = bf5xx_ac97_resume,
    .playback = {
        .stream_name = "AC97 Playback",
        .channels_min = 2,
#if defined(CONFIG_SND_BF5XX_MULTICHAN_SUPPORT)
        .channels_max = 6,
#else
        .channels_max = 2,
#endif
        .rates = SNDRV_PCM_RATE_48000,
        .formats = SNDRV_PCM_FMTBIT_S16_LE, },
    .capture = {
        .stream_name = "AC97 Capture",
        .channels_min = 2,
        .channels_max = 2,
        .rates = SNDRV_PCM_RATE_48000,
        .formats = SNDRV_PCM_FMTBIT_S16_LE, },
};

static int __devinit asoc_bfin_ac97_probe(struct platform_device *pdev)
{
    struct sport_device *sport_handle;
    int ret;

#ifdef CONFIG_SND_BF5XX_HAVE_COLD_RESET
    /* Request PB3 as reset pin */
    if (gpio_request(CONFIG_SND_BF5XX_RESET_GPIO_NUM, "SND_AD198x RESET")) {
        pr_err("Failed to request GPIO_%d for reset\n",
                CONFIG_SND_BF5XX_RESET_GPIO_NUM);
        ret =  -1;
        goto gpio_err;
    }
    gpio_direction_output(CONFIG_SND_BF5XX_RESET_GPIO_NUM, 1);
#endif

    sport_handle = sport_init(pdev, 2, sizeof(struct ac97_frame),
        PAGE_SIZE);
    if (!sport_handle) {
        ret = -ENODEV;
        goto sport_err;
    }

    /*SPORT works in TDM mode to simulate AC97 transfers*/
#if defined(CONFIG_SND_BF5XX_MULTICHAN_SUPPORT)
    ret = sport_set_multichannel(sport_handle, 16, 0x3FF, 1);
#else
    ret = sport_set_multichannel(sport_handle, 16, 0x1F, 1);
#endif
    if (ret) {
        pr_err("SPORT is busy!\n");
        ret = -EBUSY;
        goto sport_config_err;
    }

    ret = sport_config_rx(sport_handle, IRFS, 0xF, 0, (16*16-1));
    if (ret) {
        pr_err("SPORT is busy!\n");
        ret = -EBUSY;
        goto sport_config_err;
    }

    ret = sport_config_tx(sport_handle, ITFS, 0xF, 0, (16*16-1));
    if (ret) {
        pr_err("SPORT is busy!\n");
        ret = -EBUSY;
        goto sport_config_err;
    }

    ret = snd_soc_register_dai(&pdev->dev, &bfin_ac97_dai);
    if (ret) {
        pr_err("Failed to register DAI: %d\n", ret);
        goto sport_config_err;
    }

    ac97_sport_handle = sport_handle;

    return 0;

sport_config_err:
    sport_done(sport_handle);
sport_err:
#ifdef CONFIG_SND_BF5XX_HAVE_COLD_RESET
    gpio_free(CONFIG_SND_BF5XX_RESET_GPIO_NUM);
gpio_err:
#endif

    return ret;
}

static int __devexit asoc_bfin_ac97_remove(struct platform_device *pdev)
{
    struct sport_device *sport_handle = platform_get_drvdata(pdev);

    snd_soc_unregister_dai(&pdev->dev);
    sport_done(sport_handle);
#ifdef CONFIG_SND_BF5XX_HAVE_COLD_RESET
    gpio_free(CONFIG_SND_BF5XX_RESET_GPIO_NUM);
#endif

    return 0;
}

static struct platform_driver asoc_bfin_ac97_driver = {
    .driver = {
            .name = "bfin-ac97",
            .owner = THIS_MODULE,
    },

    .probe = asoc_bfin_ac97_probe,
    .remove = __devexit_p(asoc_bfin_ac97_remove),
};

module_platform_driver(asoc_bfin_ac97_driver);

MODULE_AUTHOR("Roy Huang");
MODULE_DESCRIPTION("AC97 driver for ADI Blackfin");
MODULE_LICENSE("GPL");