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-rw-r--r--sound/soc/davinci/davinci-pcm.c884
1 files changed, 884 insertions, 0 deletions
diff --git a/sound/soc/davinci/davinci-pcm.c b/sound/soc/davinci/davinci-pcm.c
new file mode 100644
index 00000000..9d35b8c1
--- /dev/null
+++ b/sound/soc/davinci/davinci-pcm.c
@@ -0,0 +1,884 @@
+/*
+ * ALSA PCM interface for the TI DAVINCI processor
+ *
+ * Author: Vladimir Barinov, <vbarinov@embeddedalley.com>
+ * Copyright: (C) 2007 MontaVista Software, Inc., <source@mvista.com>
+ * added SRAM ping/pong (C) 2008 Troy Kisky <troy.kisky@boundarydevices.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/kernel.h>
+
+#include <sound/core.h>
+#include <sound/pcm.h>
+#include <sound/pcm_params.h>
+#include <sound/soc.h>
+
+#include <asm/dma.h>
+#include <mach/edma.h>
+#include <mach/sram.h>
+
+#include "davinci-pcm.h"
+
+#ifdef DEBUG
+static void print_buf_info(int slot, char *name)
+{
+ struct edmacc_param p;
+ if (slot < 0)
+ return;
+ edma_read_slot(slot, &p);
+ printk(KERN_DEBUG "%s: 0x%x, opt=%x, src=%x, a_b_cnt=%x dst=%x\n",
+ name, slot, p.opt, p.src, p.a_b_cnt, p.dst);
+ printk(KERN_DEBUG " src_dst_bidx=%x link_bcntrld=%x src_dst_cidx=%x ccnt=%x\n",
+ p.src_dst_bidx, p.link_bcntrld, p.src_dst_cidx, p.ccnt);
+}
+#else
+static void print_buf_info(int slot, char *name)
+{
+}
+#endif
+
+static struct snd_pcm_hardware pcm_hardware_playback = {
+ .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_RESUME),
+ .formats = (SNDRV_PCM_FMTBIT_S16_LE),
+ .rates = (SNDRV_PCM_RATE_8000 | SNDRV_PCM_RATE_16000 |
+ SNDRV_PCM_RATE_22050 | SNDRV_PCM_RATE_32000 |
+ SNDRV_PCM_RATE_44100 | SNDRV_PCM_RATE_48000 |
+ SNDRV_PCM_RATE_88200 | SNDRV_PCM_RATE_96000 |
+ SNDRV_PCM_RATE_KNOT),
+ .rate_min = 8000,
+ .rate_max = 96000,
+ .channels_min = 2,
+ .channels_max = 2,
+ .buffer_bytes_max = 128 * 1024,
+ .period_bytes_min = 32,
+ .period_bytes_max = 8 * 1024,
+ .periods_min = 16,
+ .periods_max = 255,
+ .fifo_size = 0,
+};
+
+static struct snd_pcm_hardware pcm_hardware_capture = {
+ .info = (SNDRV_PCM_INFO_INTERLEAVED | SNDRV_PCM_INFO_BLOCK_TRANSFER |
+ SNDRV_PCM_INFO_MMAP | SNDRV_PCM_INFO_MMAP_VALID |
+ SNDRV_PCM_INFO_PAUSE),
+ .formats = (SNDRV_PCM_FMTBIT_S16_LE),
+ .rates = (SNDRV_PCM_RATE_8000 | SNDRV_PCM_RATE_16000 |
+ SNDRV_PCM_RATE_22050 | SNDRV_PCM_RATE_32000 |
+ SNDRV_PCM_RATE_44100 | SNDRV_PCM_RATE_48000 |
+ SNDRV_PCM_RATE_88200 | SNDRV_PCM_RATE_96000 |
+ SNDRV_PCM_RATE_KNOT),
+ .rate_min = 8000,
+ .rate_max = 96000,
+ .channels_min = 2,
+ .channels_max = 2,
+ .buffer_bytes_max = 128 * 1024,
+ .period_bytes_min = 32,
+ .period_bytes_max = 8 * 1024,
+ .periods_min = 16,
+ .periods_max = 255,
+ .fifo_size = 0,
+};
+
+/*
+ * How ping/pong works....
+ *
+ * Playback:
+ * ram_params - copys 2*ping_size from start of SDRAM to iram,
+ * links to ram_link2
+ * ram_link2 - copys rest of SDRAM to iram in ping_size units,
+ * links to ram_link
+ * ram_link - copys entire SDRAM to iram in ping_size uints,
+ * links to self
+ *
+ * asp_params - same as asp_link[0]
+ * asp_link[0] - copys from lower half of iram to asp port
+ * links to asp_link[1], triggers iram copy event on completion
+ * asp_link[1] - copys from upper half of iram to asp port
+ * links to asp_link[0], triggers iram copy event on completion
+ * triggers interrupt only needed to let upper SOC levels update position
+ * in stream on completion
+ *
+ * When playback is started:
+ * ram_params started
+ * asp_params started
+ *
+ * Capture:
+ * ram_params - same as ram_link,
+ * links to ram_link
+ * ram_link - same as playback
+ * links to self
+ *
+ * asp_params - same as playback
+ * asp_link[0] - same as playback
+ * asp_link[1] - same as playback
+ *
+ * When capture is started:
+ * asp_params started
+ */
+struct davinci_runtime_data {
+ spinlock_t lock;
+ int period; /* current DMA period */
+ int asp_channel; /* Master DMA channel */
+ int asp_link[2]; /* asp parameter link channel, ping/pong */
+ struct davinci_pcm_dma_params *params; /* DMA params */
+ int ram_channel;
+ int ram_link;
+ int ram_link2;
+ struct edmacc_param asp_params;
+ struct edmacc_param ram_params;
+};
+
+/*
+ * Not used with ping/pong
+ */
+static void davinci_pcm_enqueue_dma(struct snd_pcm_substream *substream)
+{
+ struct davinci_runtime_data *prtd = substream->runtime->private_data;
+ struct snd_pcm_runtime *runtime = substream->runtime;
+ int link = prtd->asp_link[0];
+ unsigned int period_size;
+ unsigned int dma_offset;
+ dma_addr_t dma_pos;
+ dma_addr_t src, dst;
+ unsigned short src_bidx, dst_bidx;
+ unsigned short src_cidx, dst_cidx;
+ unsigned int data_type;
+ unsigned short acnt;
+ unsigned int count;
+ unsigned int fifo_level;
+
+ period_size = snd_pcm_lib_period_bytes(substream);
+ dma_offset = prtd->period * period_size;
+ dma_pos = runtime->dma_addr + dma_offset;
+ fifo_level = prtd->params->fifo_level;
+
+ pr_debug("davinci_pcm: audio_set_dma_params_play channel = %d "
+ "dma_ptr = %x period_size=%x\n", link, dma_pos, period_size);
+
+ data_type = prtd->params->data_type;
+ count = period_size / data_type;
+ if (fifo_level)
+ count /= fifo_level;
+
+ if (substream->stream == SNDRV_PCM_STREAM_PLAYBACK) {
+ src = dma_pos;
+ dst = prtd->params->dma_addr;
+ src_bidx = data_type;
+ dst_bidx = 0;
+ src_cidx = data_type * fifo_level;
+ dst_cidx = 0;
+ } else {
+ src = prtd->params->dma_addr;
+ dst = dma_pos;
+ src_bidx = 0;
+ dst_bidx = data_type;
+ src_cidx = 0;
+ dst_cidx = data_type * fifo_level;
+ }
+
+ acnt = prtd->params->acnt;
+ edma_set_src(link, src, INCR, W8BIT);
+ edma_set_dest(link, dst, INCR, W8BIT);
+
+ edma_set_src_index(link, src_bidx, src_cidx);
+ edma_set_dest_index(link, dst_bidx, dst_cidx);
+
+ if (!fifo_level)
+ edma_set_transfer_params(link, acnt, count, 1, 0, ASYNC);
+ else
+ edma_set_transfer_params(link, acnt, fifo_level, count,
+ fifo_level, ABSYNC);
+
+ prtd->period++;
+ if (unlikely(prtd->period >= runtime->periods))
+ prtd->period = 0;
+}
+
+static void davinci_pcm_dma_irq(unsigned link, u16 ch_status, void *data)
+{
+ struct snd_pcm_substream *substream = data;
+ struct davinci_runtime_data *prtd = substream->runtime->private_data;
+
+ print_buf_info(prtd->ram_channel, "i ram_channel");
+ pr_debug("davinci_pcm: link=%d, status=0x%x\n", link, ch_status);
+
+ if (unlikely(ch_status != DMA_COMPLETE))
+ return;
+
+ if (snd_pcm_running(substream)) {
+ if (prtd->ram_channel < 0) {
+ /* No ping/pong must fix up link dma data*/
+ spin_lock(&prtd->lock);
+ davinci_pcm_enqueue_dma(substream);
+ spin_unlock(&prtd->lock);
+ }
+ snd_pcm_period_elapsed(substream);
+ }
+}
+
+static int allocate_sram(struct snd_pcm_substream *substream, unsigned size,
+ struct snd_pcm_hardware *ppcm)
+{
+ struct snd_dma_buffer *buf = &substream->dma_buffer;
+ struct snd_dma_buffer *iram_dma = NULL;
+ dma_addr_t iram_phys = 0;
+ void *iram_virt = NULL;
+
+ if (buf->private_data || !size)
+ return 0;
+
+ ppcm->period_bytes_max = size;
+ iram_virt = sram_alloc(size, &iram_phys);
+ if (!iram_virt)
+ goto exit1;
+ iram_dma = kzalloc(sizeof(*iram_dma), GFP_KERNEL);
+ if (!iram_dma)
+ goto exit2;
+ iram_dma->area = iram_virt;
+ iram_dma->addr = iram_phys;
+ memset(iram_dma->area, 0, size);
+ iram_dma->bytes = size;
+ buf->private_data = iram_dma;
+ return 0;
+exit2:
+ if (iram_virt)
+ sram_free(iram_virt, size);
+exit1:
+ return -ENOMEM;
+}
+
+/*
+ * Only used with ping/pong.
+ * This is called after runtime->dma_addr, period_bytes and data_type are valid
+ */
+static int ping_pong_dma_setup(struct snd_pcm_substream *substream)
+{
+ unsigned short ram_src_cidx, ram_dst_cidx;
+ struct snd_pcm_runtime *runtime = substream->runtime;
+ struct davinci_runtime_data *prtd = runtime->private_data;
+ struct snd_dma_buffer *iram_dma =
+ (struct snd_dma_buffer *)substream->dma_buffer.private_data;
+ struct davinci_pcm_dma_params *params = prtd->params;
+ unsigned int data_type = params->data_type;
+ unsigned int acnt = params->acnt;
+ /* divide by 2 for ping/pong */
+ unsigned int ping_size = snd_pcm_lib_period_bytes(substream) >> 1;
+ int link = prtd->asp_link[1];
+ unsigned int fifo_level = prtd->params->fifo_level;
+ unsigned int count;
+ if ((data_type == 0) || (data_type > 4)) {
+ printk(KERN_ERR "%s: data_type=%i\n", __func__, data_type);
+ return -EINVAL;
+ }
+ if (substream->stream == SNDRV_PCM_STREAM_PLAYBACK) {
+ dma_addr_t asp_src_pong = iram_dma->addr + ping_size;
+ ram_src_cidx = ping_size;
+ ram_dst_cidx = -ping_size;
+ edma_set_src(link, asp_src_pong, INCR, W8BIT);
+
+ link = prtd->asp_link[0];
+ edma_set_src_index(link, data_type, data_type * fifo_level);
+ link = prtd->asp_link[1];
+ edma_set_src_index(link, data_type, data_type * fifo_level);
+
+ link = prtd->ram_link;
+ edma_set_src(link, runtime->dma_addr, INCR, W32BIT);
+ } else {
+ dma_addr_t asp_dst_pong = iram_dma->addr + ping_size;
+ ram_src_cidx = -ping_size;
+ ram_dst_cidx = ping_size;
+ edma_set_dest(link, asp_dst_pong, INCR, W8BIT);
+
+ link = prtd->asp_link[0];
+ edma_set_dest_index(link, data_type, data_type * fifo_level);
+ link = prtd->asp_link[1];
+ edma_set_dest_index(link, data_type, data_type * fifo_level);
+
+ link = prtd->ram_link;
+ edma_set_dest(link, runtime->dma_addr, INCR, W32BIT);
+ }
+
+ if (!fifo_level) {
+ count = ping_size / data_type;
+ edma_set_transfer_params(prtd->asp_link[0], acnt, count,
+ 1, 0, ASYNC);
+ edma_set_transfer_params(prtd->asp_link[1], acnt, count,
+ 1, 0, ASYNC);
+ } else {
+ count = ping_size / (data_type * fifo_level);
+ edma_set_transfer_params(prtd->asp_link[0], acnt, fifo_level,
+ count, fifo_level, ABSYNC);
+ edma_set_transfer_params(prtd->asp_link[1], acnt, fifo_level,
+ count, fifo_level, ABSYNC);
+ }
+
+ link = prtd->ram_link;
+ edma_set_src_index(link, ping_size, ram_src_cidx);
+ edma_set_dest_index(link, ping_size, ram_dst_cidx);
+ edma_set_transfer_params(link, ping_size, 2,
+ runtime->periods, 2, ASYNC);
+
+ /* init master params */
+ edma_read_slot(prtd->asp_link[0], &prtd->asp_params);
+ edma_read_slot(prtd->ram_link, &prtd->ram_params);
+ if (substream->stream == SNDRV_PCM_STREAM_PLAYBACK) {
+ struct edmacc_param p_ram;
+ /* Copy entire iram buffer before playback started */
+ prtd->ram_params.a_b_cnt = (1 << 16) | (ping_size << 1);
+ /* 0 dst_bidx */
+ prtd->ram_params.src_dst_bidx = (ping_size << 1);
+ /* 0 dst_cidx */
+ prtd->ram_params.src_dst_cidx = (ping_size << 1);
+ prtd->ram_params.ccnt = 1;
+
+ /* Skip 1st period */
+ edma_read_slot(prtd->ram_link, &p_ram);
+ p_ram.src += (ping_size << 1);
+ p_ram.ccnt -= 1;
+ edma_write_slot(prtd->ram_link2, &p_ram);
+ /*
+ * When 1st started, ram -> iram dma channel will fill the
+ * entire iram. Then, whenever a ping/pong asp buffer finishes,
+ * 1/2 iram will be filled.
+ */
+ prtd->ram_params.link_bcntrld =
+ EDMA_CHAN_SLOT(prtd->ram_link2) << 5;
+ }
+ return 0;
+}
+
+/* 1 asp tx or rx channel using 2 parameter channels
+ * 1 ram to/from iram channel using 1 parameter channel
+ *
+ * Playback
+ * ram copy channel kicks off first,
+ * 1st ram copy of entire iram buffer completion kicks off asp channel
+ * asp tcc always kicks off ram copy of 1/2 iram buffer
+ *
+ * Record
+ * asp channel starts, tcc kicks off ram copy
+ */
+static int request_ping_pong(struct snd_pcm_substream *substream,
+ struct davinci_runtime_data *prtd,
+ struct snd_dma_buffer *iram_dma)
+{
+ dma_addr_t asp_src_ping;
+ dma_addr_t asp_dst_ping;
+ int link;
+ struct davinci_pcm_dma_params *params = prtd->params;
+
+ /* Request ram master channel */
+ link = prtd->ram_channel = edma_alloc_channel(EDMA_CHANNEL_ANY,
+ davinci_pcm_dma_irq, substream,
+ prtd->params->ram_chan_q);
+ if (link < 0)
+ goto exit1;
+
+ /* Request ram link channel */
+ link = prtd->ram_link = edma_alloc_slot(
+ EDMA_CTLR(prtd->ram_channel), EDMA_SLOT_ANY);
+ if (link < 0)
+ goto exit2;
+
+ link = prtd->asp_link[1] = edma_alloc_slot(
+ EDMA_CTLR(prtd->asp_channel), EDMA_SLOT_ANY);
+ if (link < 0)
+ goto exit3;
+
+ prtd->ram_link2 = -1;
+ if (substream->stream == SNDRV_PCM_STREAM_PLAYBACK) {
+ link = prtd->ram_link2 = edma_alloc_slot(
+ EDMA_CTLR(prtd->ram_channel), EDMA_SLOT_ANY);
+ if (link < 0)
+ goto exit4;
+ }
+ /* circle ping-pong buffers */
+ edma_link(prtd->asp_link[0], prtd->asp_link[1]);
+ edma_link(prtd->asp_link[1], prtd->asp_link[0]);
+ /* circle ram buffers */
+ edma_link(prtd->ram_link, prtd->ram_link);
+
+ if (substream->stream == SNDRV_PCM_STREAM_PLAYBACK) {
+ asp_src_ping = iram_dma->addr;
+ asp_dst_ping = params->dma_addr; /* fifo */
+ } else {
+ asp_src_ping = params->dma_addr; /* fifo */
+ asp_dst_ping = iram_dma->addr;
+ }
+ /* ping */
+ link = prtd->asp_link[0];
+ edma_set_src(link, asp_src_ping, INCR, W16BIT);
+ edma_set_dest(link, asp_dst_ping, INCR, W16BIT);
+ edma_set_src_index(link, 0, 0);
+ edma_set_dest_index(link, 0, 0);
+
+ edma_read_slot(link, &prtd->asp_params);
+ prtd->asp_params.opt &= ~(TCCMODE | EDMA_TCC(0x3f) | TCINTEN);
+ prtd->asp_params.opt |= TCCHEN | EDMA_TCC(prtd->ram_channel & 0x3f);
+ edma_write_slot(link, &prtd->asp_params);
+
+ /* pong */
+ link = prtd->asp_link[1];
+ edma_set_src(link, asp_src_ping, INCR, W16BIT);
+ edma_set_dest(link, asp_dst_ping, INCR, W16BIT);
+ edma_set_src_index(link, 0, 0);
+ edma_set_dest_index(link, 0, 0);
+
+ edma_read_slot(link, &prtd->asp_params);
+ prtd->asp_params.opt &= ~(TCCMODE | EDMA_TCC(0x3f));
+ /* interrupt after every pong completion */
+ prtd->asp_params.opt |= TCINTEN | TCCHEN |
+ EDMA_TCC(EDMA_CHAN_SLOT(prtd->ram_channel));
+ edma_write_slot(link, &prtd->asp_params);
+
+ /* ram */
+ link = prtd->ram_link;
+ edma_set_src(link, iram_dma->addr, INCR, W32BIT);
+ edma_set_dest(link, iram_dma->addr, INCR, W32BIT);
+ pr_debug("%s: audio dma channels/slots in use for ram:%u %u %u,"
+ "for asp:%u %u %u\n", __func__,
+ prtd->ram_channel, prtd->ram_link, prtd->ram_link2,
+ prtd->asp_channel, prtd->asp_link[0],
+ prtd->asp_link[1]);
+ return 0;
+exit4:
+ edma_free_channel(prtd->asp_link[1]);
+ prtd->asp_link[1] = -1;
+exit3:
+ edma_free_channel(prtd->ram_link);
+ prtd->ram_link = -1;
+exit2:
+ edma_free_channel(prtd->ram_channel);
+ prtd->ram_channel = -1;
+exit1:
+ return link;
+}
+
+static int davinci_pcm_dma_request(struct snd_pcm_substream *substream)
+{
+ struct snd_dma_buffer *iram_dma;
+ struct davinci_runtime_data *prtd = substream->runtime->private_data;
+ struct davinci_pcm_dma_params *params = prtd->params;
+ int link;
+
+ if (!params)
+ return -ENODEV;
+
+ /* Request asp master DMA channel */
+ link = prtd->asp_channel = edma_alloc_channel(params->channel,
+ davinci_pcm_dma_irq, substream,
+ prtd->params->asp_chan_q);
+ if (link < 0)
+ goto exit1;
+
+ /* Request asp link channels */
+ link = prtd->asp_link[0] = edma_alloc_slot(
+ EDMA_CTLR(prtd->asp_channel), EDMA_SLOT_ANY);
+ if (link < 0)
+ goto exit2;
+
+ iram_dma = (struct snd_dma_buffer *)substream->dma_buffer.private_data;
+ if (iram_dma) {
+ if (request_ping_pong(substream, prtd, iram_dma) == 0)
+ return 0;
+ printk(KERN_WARNING "%s: dma channel allocation failed,"
+ "not using sram\n", __func__);
+ }
+
+ /* Issue transfer completion IRQ when the channel completes a
+ * transfer, then always reload from the same slot (by a kind
+ * of loopback link). The completion IRQ handler will update
+ * the reload slot with a new buffer.
+ *
+ * REVISIT save p_ram here after setting up everything except
+ * the buffer and its length (ccnt) ... use it as a template
+ * so davinci_pcm_enqueue_dma() takes less time in IRQ.
+ */
+ edma_read_slot(link, &prtd->asp_params);
+ prtd->asp_params.opt |= TCINTEN |
+ EDMA_TCC(EDMA_CHAN_SLOT(prtd->asp_channel));
+ prtd->asp_params.link_bcntrld = EDMA_CHAN_SLOT(link) << 5;
+ edma_write_slot(link, &prtd->asp_params);
+ return 0;
+exit2:
+ edma_free_channel(prtd->asp_channel);
+ prtd->asp_channel = -1;
+exit1:
+ return link;
+}
+
+static int davinci_pcm_trigger(struct snd_pcm_substream *substream, int cmd)
+{
+ struct davinci_runtime_data *prtd = substream->runtime->private_data;
+ int ret = 0;
+
+ spin_lock(&prtd->lock);
+
+ switch (cmd) {
+ case SNDRV_PCM_TRIGGER_START:
+ case SNDRV_PCM_TRIGGER_RESUME:
+ case SNDRV_PCM_TRIGGER_PAUSE_RELEASE:
+ edma_resume(prtd->asp_channel);
+ break;
+ case SNDRV_PCM_TRIGGER_STOP:
+ case SNDRV_PCM_TRIGGER_SUSPEND:
+ case SNDRV_PCM_TRIGGER_PAUSE_PUSH:
+ edma_pause(prtd->asp_channel);
+ break;
+ default:
+ ret = -EINVAL;
+ break;
+ }
+
+ spin_unlock(&prtd->lock);
+
+ return ret;
+}
+
+static int davinci_pcm_prepare(struct snd_pcm_substream *substream)
+{
+ struct davinci_runtime_data *prtd = substream->runtime->private_data;
+
+ if (prtd->ram_channel >= 0) {
+ int ret = ping_pong_dma_setup(substream);
+ if (ret < 0)
+ return ret;
+
+ edma_write_slot(prtd->ram_channel, &prtd->ram_params);
+ edma_write_slot(prtd->asp_channel, &prtd->asp_params);
+
+ print_buf_info(prtd->ram_channel, "ram_channel");
+ print_buf_info(prtd->ram_link, "ram_link");
+ print_buf_info(prtd->ram_link2, "ram_link2");
+ print_buf_info(prtd->asp_channel, "asp_channel");
+ print_buf_info(prtd->asp_link[0], "asp_link[0]");
+ print_buf_info(prtd->asp_link[1], "asp_link[1]");
+
+ if (substream->stream == SNDRV_PCM_STREAM_PLAYBACK) {
+ /* copy 1st iram buffer */
+ edma_start(prtd->ram_channel);
+ }
+ edma_start(prtd->asp_channel);
+ return 0;
+ }
+ prtd->period = 0;
+ davinci_pcm_enqueue_dma(substream);
+
+ /* Copy self-linked parameter RAM entry into master channel */
+ edma_read_slot(prtd->asp_link[0], &prtd->asp_params);
+ edma_write_slot(prtd->asp_channel, &prtd->asp_params);
+ davinci_pcm_enqueue_dma(substream);
+ edma_start(prtd->asp_channel);
+
+ return 0;
+}
+
+static snd_pcm_uframes_t
+davinci_pcm_pointer(struct snd_pcm_substream *substream)
+{
+ struct snd_pcm_runtime *runtime = substream->runtime;
+ struct davinci_runtime_data *prtd = runtime->private_data;
+ unsigned int offset;
+ int asp_count;
+ dma_addr_t asp_src, asp_dst;
+
+ spin_lock(&prtd->lock);
+ if (prtd->ram_channel >= 0) {
+ int ram_count;
+ int mod_ram;
+ dma_addr_t ram_src, ram_dst;
+ unsigned int period_size = snd_pcm_lib_period_bytes(substream);
+ if (substream->stream == SNDRV_PCM_STREAM_PLAYBACK) {
+ /* reading ram before asp should be safe
+ * as long as the asp transfers less than a ping size
+ * of bytes between the 2 reads
+ */
+ edma_get_position(prtd->ram_channel,
+ &ram_src, &ram_dst);
+ edma_get_position(prtd->asp_channel,
+ &asp_src, &asp_dst);
+ asp_count = asp_src - prtd->asp_params.src;
+ ram_count = ram_src - prtd->ram_params.src;
+ mod_ram = ram_count % period_size;
+ mod_ram -= asp_count;
+ if (mod_ram < 0)
+ mod_ram += period_size;
+ else if (mod_ram == 0) {
+ if (snd_pcm_running(substream))
+ mod_ram += period_size;
+ }
+ ram_count -= mod_ram;
+ if (ram_count < 0)
+ ram_count += period_size * runtime->periods;
+ } else {
+ edma_get_position(prtd->ram_channel,
+ &ram_src, &ram_dst);
+ ram_count = ram_dst - prtd->ram_params.dst;
+ }
+ asp_count = ram_count;
+ } else {
+ edma_get_position(prtd->asp_channel, &asp_src, &asp_dst);
+ if (substream->stream == SNDRV_PCM_STREAM_PLAYBACK)
+ asp_count = asp_src - runtime->dma_addr;
+ else
+ asp_count = asp_dst - runtime->dma_addr;
+ }
+ spin_unlock(&prtd->lock);
+
+ offset = bytes_to_frames(runtime, asp_count);
+ if (offset >= runtime->buffer_size)
+ offset = 0;
+
+ return offset;
+}
+
+static int davinci_pcm_open(struct snd_pcm_substream *substream)
+{
+ struct snd_pcm_runtime *runtime = substream->runtime;
+ struct davinci_runtime_data *prtd;
+ struct snd_pcm_hardware *ppcm;
+ int ret = 0;
+ struct snd_soc_pcm_runtime *rtd = substream->private_data;
+ struct davinci_pcm_dma_params *pa;
+ struct davinci_pcm_dma_params *params;
+
+ pa = snd_soc_dai_get_dma_data(rtd->cpu_dai, substream);
+ if (!pa)
+ return -ENODEV;
+ params = &pa[substream->stream];
+
+ ppcm = (substream->stream == SNDRV_PCM_STREAM_PLAYBACK) ?
+ &pcm_hardware_playback : &pcm_hardware_capture;
+ allocate_sram(substream, params->sram_size, ppcm);
+ snd_soc_set_runtime_hwparams(substream, ppcm);
+ /* ensure that buffer size is a multiple of period size */
+ ret = snd_pcm_hw_constraint_integer(runtime,
+ SNDRV_PCM_HW_PARAM_PERIODS);
+ if (ret < 0)
+ return ret;
+
+ prtd = kzalloc(sizeof(struct davinci_runtime_data), GFP_KERNEL);
+ if (prtd == NULL)
+ return -ENOMEM;
+
+ spin_lock_init(&prtd->lock);
+ prtd->params = params;
+ prtd->asp_channel = -1;
+ prtd->asp_link[0] = prtd->asp_link[1] = -1;
+ prtd->ram_channel = -1;
+ prtd->ram_link = -1;
+ prtd->ram_link2 = -1;
+
+ runtime->private_data = prtd;
+
+ ret = davinci_pcm_dma_request(substream);
+ if (ret) {
+ printk(KERN_ERR "davinci_pcm: Failed to get dma channels\n");
+ kfree(prtd);
+ }
+
+ return ret;
+}
+
+static int davinci_pcm_close(struct snd_pcm_substream *substream)
+{
+ struct snd_pcm_runtime *runtime = substream->runtime;
+ struct davinci_runtime_data *prtd = runtime->private_data;
+
+ if (prtd->ram_channel >= 0)
+ edma_stop(prtd->ram_channel);
+ if (prtd->asp_channel >= 0)
+ edma_stop(prtd->asp_channel);
+ if (prtd->asp_link[0] >= 0)
+ edma_unlink(prtd->asp_link[0]);
+ if (prtd->asp_link[1] >= 0)
+ edma_unlink(prtd->asp_link[1]);
+ if (prtd->ram_link >= 0)
+ edma_unlink(prtd->ram_link);
+
+ if (prtd->asp_link[0] >= 0)
+ edma_free_slot(prtd->asp_link[0]);
+ if (prtd->asp_link[1] >= 0)
+ edma_free_slot(prtd->asp_link[1]);
+ if (prtd->asp_channel >= 0)
+ edma_free_channel(prtd->asp_channel);
+ if (prtd->ram_link >= 0)
+ edma_free_slot(prtd->ram_link);
+ if (prtd->ram_link2 >= 0)
+ edma_free_slot(prtd->ram_link2);
+ if (prtd->ram_channel >= 0)
+ edma_free_channel(prtd->ram_channel);
+
+ kfree(prtd);
+
+ return 0;
+}
+
+static int davinci_pcm_hw_params(struct snd_pcm_substream *substream,
+ struct snd_pcm_hw_params *hw_params)
+{
+ return snd_pcm_lib_malloc_pages(substream,
+ params_buffer_bytes(hw_params));
+}
+
+static int davinci_pcm_hw_free(struct snd_pcm_substream *substream)
+{
+ return snd_pcm_lib_free_pages(substream);
+}
+
+static int davinci_pcm_mmap(struct snd_pcm_substream *substream,
+ struct vm_area_struct *vma)
+{
+ struct snd_pcm_runtime *runtime = substream->runtime;
+
+ return dma_mmap_writecombine(substream->pcm->card->dev, vma,
+ runtime->dma_area,
+ runtime->dma_addr,
+ runtime->dma_bytes);
+}
+
+static struct snd_pcm_ops davinci_pcm_ops = {
+ .open = davinci_pcm_open,
+ .close = davinci_pcm_close,
+ .ioctl = snd_pcm_lib_ioctl,
+ .hw_params = davinci_pcm_hw_params,
+ .hw_free = davinci_pcm_hw_free,
+ .prepare = davinci_pcm_prepare,
+ .trigger = davinci_pcm_trigger,
+ .pointer = davinci_pcm_pointer,
+ .mmap = davinci_pcm_mmap,
+};
+
+static int davinci_pcm_preallocate_dma_buffer(struct snd_pcm *pcm, int stream,
+ size_t size)
+{
+ struct snd_pcm_substream *substream = pcm->streams[stream].substream;
+ struct snd_dma_buffer *buf = &substream->dma_buffer;
+
+ buf->dev.type = SNDRV_DMA_TYPE_DEV;
+ buf->dev.dev = pcm->card->dev;
+ buf->private_data = NULL;
+ buf->area = dma_alloc_writecombine(pcm->card->dev, size,
+ &buf->addr, GFP_KERNEL);
+
+ pr_debug("davinci_pcm: preallocate_dma_buffer: area=%p, addr=%p, "
+ "size=%d\n", (void *) buf->area, (void *) buf->addr, size);
+
+ if (!buf->area)
+ return -ENOMEM;
+
+ buf->bytes = size;
+ return 0;
+}
+
+static void davinci_pcm_free(struct snd_pcm *pcm)
+{
+ struct snd_pcm_substream *substream;
+ struct snd_dma_buffer *buf;
+ int stream;
+
+ for (stream = 0; stream < 2; stream++) {
+ struct snd_dma_buffer *iram_dma;
+ substream = pcm->streams[stream].substream;
+ if (!substream)
+ continue;
+
+ buf = &substream->dma_buffer;
+ if (!buf->area)
+ continue;
+
+ dma_free_writecombine(pcm->card->dev, buf->bytes,
+ buf->area, buf->addr);
+ buf->area = NULL;
+ iram_dma = buf->private_data;
+ if (iram_dma) {
+ sram_free(iram_dma->area, iram_dma->bytes);
+ kfree(iram_dma);
+ }
+ }
+}
+
+static u64 davinci_pcm_dmamask = 0xffffffff;
+
+static int davinci_pcm_new(struct snd_card *card,
+ struct snd_soc_dai *dai, struct snd_pcm *pcm)
+{
+ int ret;
+
+ if (!card->dev->dma_mask)
+ card->dev->dma_mask = &davinci_pcm_dmamask;
+ if (!card->dev->coherent_dma_mask)
+ card->dev->coherent_dma_mask = 0xffffffff;
+
+ if (dai->driver->playback.channels_min) {
+ ret = davinci_pcm_preallocate_dma_buffer(pcm,
+ SNDRV_PCM_STREAM_PLAYBACK,
+ pcm_hardware_playback.buffer_bytes_max);
+ if (ret)
+ return ret;
+ }
+
+ if (dai->driver->capture.channels_min) {
+ ret = davinci_pcm_preallocate_dma_buffer(pcm,
+ SNDRV_PCM_STREAM_CAPTURE,
+ pcm_hardware_capture.buffer_bytes_max);
+ if (ret)
+ return ret;
+ }
+
+ return 0;
+}
+
+static struct snd_soc_platform_driver davinci_soc_platform = {
+ .ops = &davinci_pcm_ops,
+ .pcm_new = davinci_pcm_new,
+ .pcm_free = davinci_pcm_free,
+};
+
+static int __devinit davinci_soc_platform_probe(struct platform_device *pdev)
+{
+ return snd_soc_register_platform(&pdev->dev, &davinci_soc_platform);
+}
+
+static int __devexit davinci_soc_platform_remove(struct platform_device *pdev)
+{
+ snd_soc_unregister_platform(&pdev->dev);
+ return 0;
+}
+
+static struct platform_driver davinci_pcm_driver = {
+ .driver = {
+ .name = "davinci-pcm-audio",
+ .owner = THIS_MODULE,
+ },
+
+ .probe = davinci_soc_platform_probe,
+ .remove = __devexit_p(davinci_soc_platform_remove),
+};
+
+static int __init snd_davinci_pcm_init(void)
+{
+ return platform_driver_register(&davinci_pcm_driver);
+}
+module_init(snd_davinci_pcm_init);
+
+static void __exit snd_davinci_pcm_exit(void)
+{
+ platform_driver_unregister(&davinci_pcm_driver);
+}
+module_exit(snd_davinci_pcm_exit);
+
+MODULE_AUTHOR("Vladimir Barinov");
+MODULE_DESCRIPTION("TI DAVINCI PCM DMA module");
+MODULE_LICENSE("GPL");