ASoC: Add driver for s6000 I2S interface

This patch adds a driver for the I2S interface found on Stretch s6000
family processors.

Signed-off-by: Daniel Glöckner <dg@emlix.com>
Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>

1 files changed, 497 insertions, 0 deletions

diff --git a/sound/soc/s6000/s6000-pcm.c b/sound/soc/s6000/s6000-pcm.c
new file mode 100644
index 000000000000..83b8028e209d
--- /dev/null
+++ b/sound/soc/s6000/s6000-pcm.c
@@ -0,0 +1,497 @@
+/*
+ * ALSA PCM interface for the Stetch s6000 family
+ *
+ * Author:      Daniel Gloeckner, <dg@emlix.com>
+ * Copyright:   (C) 2009 emlix GmbH <info@emlix.com>
+ *
+ * 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/module.h>
+#include <linux/init.h>
+#include <linux/platform_device.h>
+#include <linux/slab.h>
+#include <linux/dma-mapping.h>
+#include <linux/interrupt.h>
+
+#include <sound/core.h>
+#include <sound/pcm.h>
+#include <sound/pcm_params.h>
+#include <sound/soc.h>
+
+#include <asm/dma.h>
+#include <variant/dmac.h>
+
+#include "s6000-pcm.h"
+
+#define S6_PCM_PREALLOCATE_SIZE (96 * 1024)
+#define S6_PCM_PREALLOCATE_MAX  (2048 * 1024)
+
+static struct snd_pcm_hardware s6000_pcm_hardware = {
+        .info = (SNDRV_PCM_INFO_INTERLEAVED | SNDRV_PCM_INFO_BLOCK_TRANSFER |
+                 SNDRV_PCM_INFO_MMAP | SNDRV_PCM_INFO_MMAP_VALID |
+                 SNDRV_PCM_INFO_PAUSE | SNDRV_PCM_INFO_JOINT_DUPLEX),
+        .formats = (SNDRV_PCM_FMTBIT_S16_LE | SNDRV_PCM_FMTBIT_S32_LE),
+        .rates = (SNDRV_PCM_RATE_CONTINUOUS | SNDRV_PCM_RATE_5512 | \
+                  SNDRV_PCM_RATE_8000_192000),
+        .rate_min = 0,
+        .rate_max = 1562500,
+        .channels_min = 2,
+        .channels_max = 8,
+        .buffer_bytes_max = 0x7ffffff0,
+        .period_bytes_min = 16,
+        .period_bytes_max = 0xfffff0,
+        .periods_min = 2,
+        .periods_max = 1024, /* no limit */
+        .fifo_size = 0,
+};
+
+struct s6000_runtime_data {
+        spinlock_t lock;
+        int period;             /* current DMA period */
+};
+
+static void s6000_pcm_enqueue_dma(struct snd_pcm_substream *substream)
+{
+        struct snd_pcm_runtime *runtime = substream->runtime;
+        struct s6000_runtime_data *prtd = runtime->private_data;
+        struct snd_soc_pcm_runtime *soc_runtime = substream->private_data;
+        struct s6000_pcm_dma_params *par = soc_runtime->dai->cpu_dai->dma_data;
+        int channel;
+        unsigned int period_size;
+        unsigned int dma_offset;
+        dma_addr_t dma_pos;
+        dma_addr_t src, dst;
+
+        period_size = snd_pcm_lib_period_bytes(substream);
+        dma_offset = prtd->period * period_size;
+        dma_pos = runtime->dma_addr + dma_offset;
+
+        if (substream->stream == SNDRV_PCM_STREAM_PLAYBACK) {
+                src = dma_pos;
+                dst = par->sif_out;
+                channel = par->dma_out;
+        } else {
+                src = par->sif_in;
+                dst = dma_pos;
+                channel = par->dma_in;
+        }
+
+        if (!s6dmac_channel_enabled(DMA_MASK_DMAC(channel),
+                                    DMA_INDEX_CHNL(channel)))
+                return;
+
+        if (s6dmac_fifo_full(DMA_MASK_DMAC(channel), DMA_INDEX_CHNL(channel))) {
+                printk(KERN_ERR "s6000-pcm: fifo full\n");
+                return;
+        }
+
+        BUG_ON(period_size & 15);
+        s6dmac_put_fifo(DMA_MASK_DMAC(channel), DMA_INDEX_CHNL(channel),
+                        src, dst, period_size);
+
+        prtd->period++;
+        if (unlikely(prtd->period >= runtime->periods))
+                prtd->period = 0;
+}
+
+static irqreturn_t s6000_pcm_irq(int irq, void *data)
+{
+        struct snd_pcm *pcm = data;
+        struct snd_soc_pcm_runtime *runtime = pcm->private_data;
+        struct s6000_pcm_dma_params *params = runtime->dai->cpu_dai->dma_data;
+        struct s6000_runtime_data *prtd;
+        unsigned int has_xrun;
+        int i, ret = IRQ_NONE;
+        u32 channel[2] = {
+                [SNDRV_PCM_STREAM_PLAYBACK] = params->dma_out,
+                [SNDRV_PCM_STREAM_CAPTURE] = params->dma_in
+        };
+
+        has_xrun = params->check_xrun(runtime->dai->cpu_dai);
+
+        for (i = 0; i < ARRAY_SIZE(channel); ++i) {
+                struct snd_pcm_substream *substream = pcm->streams[i].substream;
+                unsigned int pending;
+
+                if (!channel[i])
+                        continue;
+
+                if (unlikely(has_xrun & (1 << i)) &&
+                    substream->runtime &&
+                    snd_pcm_running(substream)) {
+                        dev_dbg(pcm->dev, "xrun\n");
+                        snd_pcm_stop(substream, SNDRV_PCM_STATE_XRUN);
+                        ret = IRQ_HANDLED;
+                }
+
+                pending = s6dmac_int_sources(DMA_MASK_DMAC(channel[i]),
+                                             DMA_INDEX_CHNL(channel[i]));
+
+                if (pending & 1) {
+                        ret = IRQ_HANDLED;
+                        if (likely(substream->runtime &&
+                                   snd_pcm_running(substream))) {
+                                snd_pcm_period_elapsed(substream);
+                                dev_dbg(pcm->dev, "period elapsed %x %x\n",
+                                       s6dmac_cur_src(DMA_MASK_DMAC(channel[i]),
+                                                   DMA_INDEX_CHNL(channel[i])),
+                                       s6dmac_cur_dst(DMA_MASK_DMAC(channel[i]),
+                                                   DMA_INDEX_CHNL(channel[i])));
+                                prtd = substream->runtime->private_data;
+                                spin_lock(&prtd->lock);
+                                s6000_pcm_enqueue_dma(substream);
+                                spin_unlock(&prtd->lock);
+                        }
+                }
+
+                if (unlikely(pending & ~7)) {
+                        if (pending & (1 << 3))
+                                printk(KERN_WARNING
+                                       "s6000-pcm: DMA %x Underflow\n",
+                                       channel[i]);
+                        if (pending & (1 << 4))
+                                printk(KERN_WARNING
+                                       "s6000-pcm: DMA %x Overflow\n",
+                                       channel[i]);
+                        if (pending & 0x1e0)
+                                printk(KERN_WARNING
+                                       "s6000-pcm: DMA %x Master Error "
+                                       "(mask %x)\n",
+                                       channel[i], pending >> 5);
+
+                }
+        }
+
+        return ret;
+}
+
+static int s6000_pcm_start(struct snd_pcm_substream *substream)
+{
+        struct s6000_runtime_data *prtd = substream->runtime->private_data;
+        struct snd_soc_pcm_runtime *soc_runtime = substream->private_data;
+        struct s6000_pcm_dma_params *par = soc_runtime->dai->cpu_dai->dma_data;
+        unsigned long flags;
+        int srcinc;
+        u32 dma;
+
+        spin_lock_irqsave(&prtd->lock, flags);
+
+        if (substream->stream == SNDRV_PCM_STREAM_PLAYBACK) {
+                srcinc = 1;
+                dma = par->dma_out;
+        } else {
+                srcinc = 0;
+                dma = par->dma_in;
+        }
+        s6dmac_enable_chan(DMA_MASK_DMAC(dma), DMA_INDEX_CHNL(dma),
+                           1 /* priority 1 (0 is max) */,
+                           0 /* peripheral requests w/o xfer length mode */,
+                           srcinc /* source address increment */,
+                           srcinc^1 /* destination address increment */,
+                           0 /* chunksize 0 (skip impossible on this dma) */,
+                           0 /* source skip after chunk (impossible) */,
+                           0 /* destination skip after chunk (impossible) */,
+                           4 /* 16 byte burst size */,
+                           -1 /* don't conserve bandwidth */,
+                           0 /* low watermark irq descriptor theshold */,
+                           0 /* disable hardware timestamps */,
+                           1 /* enable channel */);
+
+        s6000_pcm_enqueue_dma(substream);
+        s6000_pcm_enqueue_dma(substream);
+
+        spin_unlock_irqrestore(&prtd->lock, flags);
+
+        return 0;
+}
+
+static int s6000_pcm_stop(struct snd_pcm_substream *substream)
+{
+        struct s6000_runtime_data *prtd = substream->runtime->private_data;
+        struct snd_soc_pcm_runtime *soc_runtime = substream->private_data;
+        struct s6000_pcm_dma_params *par = soc_runtime->dai->cpu_dai->dma_data;
+        unsigned long flags;
+        u32 channel;
+
+        if (substream->stream == SNDRV_PCM_STREAM_PLAYBACK)
+                channel = par->dma_out;
+        else
+                channel = par->dma_in;
+
+        s6dmac_set_terminal_count(DMA_MASK_DMAC(channel),
+                                  DMA_INDEX_CHNL(channel), 0);
+
+        spin_lock_irqsave(&prtd->lock, flags);
+
+        s6dmac_disable_chan(DMA_MASK_DMAC(channel), DMA_INDEX_CHNL(channel));
+
+        spin_unlock_irqrestore(&prtd->lock, flags);
+
+        return 0;
+}
+
+static int s6000_pcm_trigger(struct snd_pcm_substream *substream, int cmd)
+{
+        struct snd_soc_pcm_runtime *soc_runtime = substream->private_data;
+        struct s6000_pcm_dma_params *par = soc_runtime->dai->cpu_dai->dma_data;
+        int ret;
+
+        ret = par->trigger(substream, cmd, 0);
+        if (ret < 0)
+                return ret;
+
+        switch (cmd) {
+        case SNDRV_PCM_TRIGGER_START:
+        case SNDRV_PCM_TRIGGER_RESUME:
+        case SNDRV_PCM_TRIGGER_PAUSE_RELEASE:
+                ret = s6000_pcm_start(substream);
+                break;
+        case SNDRV_PCM_TRIGGER_STOP:
+        case SNDRV_PCM_TRIGGER_SUSPEND:
+        case SNDRV_PCM_TRIGGER_PAUSE_PUSH:
+                ret = s6000_pcm_stop(substream);
+                break;
+        default:
+                ret = -EINVAL;
+        }
+        if (ret < 0)
+                return ret;
+
+        return par->trigger(substream, cmd, 1);
+}
+
+static int s6000_pcm_prepare(struct snd_pcm_substream *substream)
+{
+        struct s6000_runtime_data *prtd = substream->runtime->private_data;
+
+        prtd->period = 0;
+
+        return 0;
+}
+
+static snd_pcm_uframes_t s6000_pcm_pointer(struct snd_pcm_substream *substream)
+{
+        struct snd_soc_pcm_runtime *soc_runtime = substream->private_data;
+        struct s6000_pcm_dma_params *par = soc_runtime->dai->cpu_dai->dma_data;
+        struct snd_pcm_runtime *runtime = substream->runtime;
+        struct s6000_runtime_data *prtd = runtime->private_data;
+        unsigned long flags;
+        unsigned int offset;
+        dma_addr_t count;
+
+        spin_lock_irqsave(&prtd->lock, flags);
+
+        if (substream->stream == SNDRV_PCM_STREAM_PLAYBACK)
+                count = s6dmac_cur_src(DMA_MASK_DMAC(par->dma_out),
+                                       DMA_INDEX_CHNL(par->dma_out));
+        else
+                count = s6dmac_cur_dst(DMA_MASK_DMAC(par->dma_in),
+                                       DMA_INDEX_CHNL(par->dma_in));
+
+        count -= runtime->dma_addr;
+
+        spin_unlock_irqrestore(&prtd->lock, flags);
+
+        offset = bytes_to_frames(runtime, count);
+        if (unlikely(offset >= runtime->buffer_size))
+                offset = 0;
+
+        return offset;
+}
+
+static int s6000_pcm_open(struct snd_pcm_substream *substream)
+{
+        struct snd_soc_pcm_runtime *soc_runtime = substream->private_data;
+        struct s6000_pcm_dma_params *par = soc_runtime->dai->cpu_dai->dma_data;
+        struct snd_pcm_runtime *runtime = substream->runtime;
+        struct s6000_runtime_data *prtd;
+        int ret;
+
+        snd_soc_set_runtime_hwparams(substream, &s6000_pcm_hardware);
+
+        ret = snd_pcm_hw_constraint_step(runtime, 0,
+                                         SNDRV_PCM_HW_PARAM_PERIOD_BYTES, 16);
+        if (ret < 0)
+                return ret;
+        ret = snd_pcm_hw_constraint_step(runtime, 0,
+                                         SNDRV_PCM_HW_PARAM_BUFFER_BYTES, 16);
+        if (ret < 0)
+                return ret;
+        ret = snd_pcm_hw_constraint_integer(runtime,
+                                            SNDRV_PCM_HW_PARAM_PERIODS);
+        if (ret < 0)
+                return ret;
+
+        if (par->same_rate) {
+                int rate;
+                spin_lock(&par->lock); /* needed? */
+                rate = par->rate;
+                spin_unlock(&par->lock);
+                if (rate != -1) {
+                        ret = snd_pcm_hw_constraint_minmax(runtime,
+                                                        SNDRV_PCM_HW_PARAM_RATE,
+                                                        rate, rate);
+                        if (ret < 0)
+                                return ret;
+                }
+        }
+
+        prtd = kzalloc(sizeof(struct s6000_runtime_data), GFP_KERNEL);
+        if (prtd == NULL)
+                return -ENOMEM;
+
+        spin_lock_init(&prtd->lock);
+
+        runtime->private_data = prtd;
+
+        return 0;
+}
+
+static int s6000_pcm_close(struct snd_pcm_substream *substream)
+{
+        struct snd_pcm_runtime *runtime = substream->runtime;
+        struct s6000_runtime_data *prtd = runtime->private_data;
+
+        kfree(prtd);
+
+        return 0;
+}
+
+static int s6000_pcm_hw_params(struct snd_pcm_substream *substream,
+                                 struct snd_pcm_hw_params *hw_params)
+{
+        struct snd_soc_pcm_runtime *soc_runtime = substream->private_data;
+        struct s6000_pcm_dma_params *par = soc_runtime->dai->cpu_dai->dma_data;
+        int ret;
+        ret = snd_pcm_lib_malloc_pages(substream,
+                                       params_buffer_bytes(hw_params));
+        if (ret < 0) {
+                printk(KERN_WARNING "s6000-pcm: allocation of memory failed\n");
+                return ret;
+        }
+
+        if (par->same_rate) {
+                spin_lock(&par->lock);
+                if (par->rate == -1 ||
+                    !(par->in_use & ~(1 << substream->stream))) {
+                        par->rate = params_rate(hw_params);
+                        par->in_use |= 1 << substream->stream;
+                } else if (params_rate(hw_params) != par->rate) {
+                        snd_pcm_lib_free_pages(substream);
+                        par->in_use &= ~(1 << substream->stream);
+                        ret = -EBUSY;
+                }
+                spin_unlock(&par->lock);
+        }
+        return ret;
+}
+
+static int s6000_pcm_hw_free(struct snd_pcm_substream *substream)
+{
+        struct snd_soc_pcm_runtime *soc_runtime = substream->private_data;
+        struct s6000_pcm_dma_params *par = soc_runtime->dai->cpu_dai->dma_data;
+
+        spin_lock(&par->lock);
+        par->in_use &= ~(1 << substream->stream);
+        if (!par->in_use)
+                par->rate = -1;
+        spin_unlock(&par->lock);
+
+        return snd_pcm_lib_free_pages(substream);
+}
+
+static struct snd_pcm_ops s6000_pcm_ops = {
+        .open =         s6000_pcm_open,
+        .close =        s6000_pcm_close,
+        .ioctl =        snd_pcm_lib_ioctl,
+        .hw_params =    s6000_pcm_hw_params,
+        .hw_free =      s6000_pcm_hw_free,
+        .trigger =      s6000_pcm_trigger,
+        .prepare =      s6000_pcm_prepare,
+        .pointer =      s6000_pcm_pointer,
+};
+
+static void s6000_pcm_free(struct snd_pcm *pcm)
+{
+        struct snd_soc_pcm_runtime *runtime = pcm->private_data;
+        struct s6000_pcm_dma_params *params = runtime->dai->cpu_dai->dma_data;
+
+        free_irq(params->irq, pcm);
+        snd_pcm_lib_preallocate_free_for_all(pcm);
+}
+
+static u64 s6000_pcm_dmamask = DMA_32BIT_MASK;
+
+static int s6000_pcm_new(struct snd_card *card,
+                         struct snd_soc_dai *dai, struct snd_pcm *pcm)
+{
+        struct snd_soc_pcm_runtime *runtime = pcm->private_data;
+        struct s6000_pcm_dma_params *params = runtime->dai->cpu_dai->dma_data;
+        int res;
+
+        if (!card->dev->dma_mask)
+                card->dev->dma_mask = &s6000_pcm_dmamask;
+        if (!card->dev->coherent_dma_mask)
+                card->dev->coherent_dma_mask = DMA_32BIT_MASK;
+
+        if (params->dma_in) {
+                s6dmac_disable_chan(DMA_MASK_DMAC(params->dma_in),
+                                    DMA_INDEX_CHNL(params->dma_in));
+                s6dmac_int_sources(DMA_MASK_DMAC(params->dma_in),
+                                   DMA_INDEX_CHNL(params->dma_in));
+        }
+
+        if (params->dma_out) {
+                s6dmac_disable_chan(DMA_MASK_DMAC(params->dma_out),
+                                    DMA_INDEX_CHNL(params->dma_out));
+                s6dmac_int_sources(DMA_MASK_DMAC(params->dma_out),
+                                   DMA_INDEX_CHNL(params->dma_out));
+        }
+
+        res = request_irq(params->irq, s6000_pcm_irq, IRQF_SHARED,
+                          s6000_soc_platform.name, pcm);
+        if (res) {
+                printk(KERN_ERR "s6000-pcm couldn't get IRQ\n");
+                return res;
+        }
+
+        res = snd_pcm_lib_preallocate_pages_for_all(pcm,
+                                                    SNDRV_DMA_TYPE_DEV,
+                                                    card->dev,
+                                                    S6_PCM_PREALLOCATE_SIZE,
+                                                    S6_PCM_PREALLOCATE_MAX);
+        if (res)
+                printk(KERN_WARNING "s6000-pcm: preallocation failed\n");
+
+        spin_lock_init(&params->lock);
+        params->in_use = 0;
+        params->rate = -1;
+        return 0;
+}
+
+struct snd_soc_platform s6000_soc_platform = {
+        .name =         "s6000-audio",
+        .pcm_ops =      &s6000_pcm_ops,
+        .pcm_new =      s6000_pcm_new,
+        .pcm_free =     s6000_pcm_free,
+};
+EXPORT_SYMBOL_GPL(s6000_soc_platform);
+
+static int __init s6000_pcm_init(void)
+{
+        return snd_soc_register_platform(&s6000_soc_platform);
+}
+module_init(s6000_pcm_init);
+
+static void __exit s6000_pcm_exit(void)
+{
+        snd_soc_unregister_platform(&s6000_soc_platform);
+}
+module_exit(s6000_pcm_exit);
+
+MODULE_AUTHOR("Daniel Gloeckner");
+MODULE_DESCRIPTION("Stretch s6000 family PCM DMA module");
+MODULE_LICENSE("GPL");