1 files changed, 461 insertions, 0 deletions
diff --git a/sound/soc/stmp3xxx/stmp3xxx_pcm.c b/sound/soc/stmp3xxx/stmp3xxx_pcm.c
new file mode 100644
index 000000000000..21cf86200668
--- /dev/null
+++ b/sound/soc/stmp3xxx/stmp3xxx_pcm.c
@@ -0,0 +1,461 @@
+/*
+ * ASoC PCM interface for Freescale STMP37XX/STMP378X ADC/DAC
+ *
+ * Author: Vladislav Buzov <vbuzov@embeddedalley.com>
+ *
+ * Copyright 2008-2009 Freescale Semiconductor, Inc. All Rights Reserved.
+ * Copyright 2008 Embedded Alley Solutions, Inc All Rights Reserved.
+ */
+
+/*
+ * The code contained herein is licensed under the GNU General Public
+ * License. You may obtain a copy of the GNU General Public License
+ * Version 2 or later at the following locations:
+ *
+ * http://www.opensource.org/licenses/gpl-license.html
+ * http://www.gnu.org/copyleft/gpl.html
+ */
+#include <linux/module.h>
+#include <linux/init.h>
+#include <linux/platform_device.h>
+#include <linux/slab.h>
+#include <linux/interrupt.h>
+#include <linux/dma-mapping.h>
+
+#include <sound/core.h>
+#include <sound/pcm.h>
+#include <sound/pcm_params.h>
+#include <sound/soc.h>
+
+#include <mach/dma.h>
+#include <mach/hardware.h>
+#include <mach/platform.h>
+
+#include <mach/regs-apbx.h>
+
+#include "stmp3xxx_pcm.h"
+
+static const struct snd_pcm_hardware stmp3xxx_pcm_hardware = {
+	.info			= SNDRV_PCM_INFO_MMAP |
+				  SNDRV_PCM_INFO_MMAP_VALID |
+				  SNDRV_PCM_INFO_PAUSE |
+				  SNDRV_PCM_INFO_RESUME |
+				  SNDRV_PCM_INFO_INTERLEAVED,
+	.formats		= SNDRV_PCM_FMTBIT_S16_LE |
+				  SNDRV_PCM_FMTBIT_S32_LE,
+	.channels_min		= 2,
+	.channels_max		= 2,
+	.period_bytes_min	= 32,
+	.period_bytes_max	= 8192,
+	.periods_min		= 1,
+	.periods_max		= 255,
+	.buffer_bytes_max	= 64 * 1024,
+	.fifo_size		= 32,
+};
+
+/*
+ * Required to request DMA channels
+ */
+struct device *stmp3xxx_pcm_dev;
+
+struct stmp3xxx_runtime_data {
+	u32 dma_ch;
+	u32 dma_period;
+	u32 dma_totsize;
+
+	struct stmp3xxx_pcm_dma_params *params;
+	struct stmp3xxx_dma_descriptor *dma_desc_array;
+};
+
+static irqreturn_t stmp3xxx_pcm_dma_irq(int irq, void *dev_id)
+{
+	struct snd_pcm_substream *substream = dev_id;
+	struct stmp3xxx_runtime_data *prtd = substream->runtime->private_data;
+
+#ifdef CONFIG_ARCH_STMP37XX
+	u32 err_mask = 1 << (16 + prtd->params->dma_ch);
+#endif
+#ifdef CONFIG_ARCH_STMP378X
+	u32 err_mask = 1 << prtd->params->dma_ch;
+#endif
+	u32 irq_mask = 1 << prtd->params->dma_ch;
+
+#ifdef CONFIG_ARCH_STMP37XX
+	if (__raw_readl(REGS_APBX_BASE + HW_APBX_CTRL1) & err_mask) {
+#endif
+#ifdef CONFIG_ARCH_STMP378X
+	if (__raw_readl(REGS_APBX_BASE + HW_APBX_CTRL2) & err_mask) {
+#endif
+		printk(KERN_WARNING "%s: DMA audio channel %d (%s) error\n",
+		       __func__, prtd->params->dma_ch, prtd->params->name);
+#ifdef CONFIG_ARCH_STMP37XX
+		stmp3xxx_clearl(err_mask, REGS_APBX_BASE + HW_APBX_CTRL1);
+#endif
+#ifdef CONFIG_ARCH_STMP378X
+		stmp3xxx_clearl(err_mask, REGS_APBX_BASE + HW_APBX_CTRL2);
+#endif
+	} else if (__raw_readl(REGS_APBX_BASE + HW_APBX_CTRL1) & irq_mask) {
+		stmp3xxx_dma_clear_interrupt(prtd->dma_ch);
+		snd_pcm_period_elapsed(substream);
+	} else
+		printk(KERN_WARNING "%s: Unknown interrupt\n", __func__);
+
+	return IRQ_HANDLED;
+}
+
+/*
+ * Make a circular DMA descriptor list
+ */
+static int stmp3xxx_pcm_prepare(struct snd_pcm_substream *substream)
+{
+	struct snd_pcm_runtime *runtime = substream->runtime;
+	struct stmp3xxx_runtime_data *prtd = runtime->private_data;
+	dma_addr_t dma_buffer_phys;
+	int periods_num, playback, i;
+
+	playback = substream->stream == SNDRV_PCM_STREAM_PLAYBACK ? 1 : 0;
+	periods_num = prtd->dma_totsize / prtd->dma_period;
+	dma_buffer_phys = runtime->dma_addr;
+
+	/* Reset DMA channel, enable interrupt */
+	stmp3xxx_dma_reset_channel(prtd->dma_ch);
+
+	/* Set up a DMA chain to sent DMA buffer */
+	for (i = 0; i < periods_num; i++) {
+		int next = (i + 1) % periods_num;
+		u32 cmd = 0;
+
+		/* Link with previous command */
+		prtd->dma_desc_array[i].command->next =
+				prtd->dma_desc_array[next].handle;
+
+		prtd->dma_desc_array[i].next_descr =
+				&prtd->dma_desc_array[next];
+
+		cmd = BF(prtd->dma_period, APBX_CHn_CMD_XFER_COUNT) |
+		      BM_APBX_CHn_CMD_IRQONCMPLT |
+		      BM_APBX_CHn_CMD_CHAIN;
+
+		/* Set DMA direction */
+		if (playback)
+			cmd |= BF(BV_APBX_CHn_CMD_COMMAND__DMA_READ,
+					APBX_CHn_CMD_COMMAND);
+		else
+			cmd |= BF(BV_APBX_CHn_CMD_COMMAND__DMA_WRITE,
+					APBX_CHn_CMD_COMMAND);
+
+		prtd->dma_desc_array[i].command->cmd = cmd;
+		prtd->dma_desc_array[i].command->buf_ptr = dma_buffer_phys;
+
+		/* Next data chunk */
+		dma_buffer_phys += prtd->dma_period;
+	}
+
+	return 0;
+}
+
+/*
+ * Stop circular DMA descriptor list
+ * We should not stop DMA in a middle of current transaction once we receive
+ * stop request from ALSA core. This function finds the next DMA descriptor
+ * and set it up to decrement DMA channel semaphore. So the current transaction
+ * is the last data transfer.
+ */
+static void stmp3xxx_pcm_stop(struct snd_pcm_substream *substream)
+{
+	struct snd_pcm_runtime *runtime = substream->runtime;
+	struct stmp3xxx_runtime_data *prtd = runtime->private_data;
+	dma_addr_t pos;
+	int desc;
+
+	/* Freez DMA channel for a moment */
+	stmp3xxx_dma_freeze(prtd->dma_ch);
+
+	/* Find current DMA descriptor */
+	pos = __raw_readl(REGS_APBX_BASE +
+			HW_APBX_CHn_BAR(prtd->params->dma_ch));
+	desc = (pos - runtime->dma_addr) / prtd->dma_period;
+
+	/* Set up the next descriptor to decrement DMA channel sempahore */
+	prtd->dma_desc_array[desc].next_descr->command->cmd
+					= BM_APBX_CHn_CMD_SEMAPHORE;
+
+	/* Let the current DMA transaction finish */
+	stmp3xxx_dma_unfreeze(prtd->dma_ch);
+}
+
+static int stmp3xxx_pcm_trigger(struct snd_pcm_substream *substream, int cmd)
+{
+	struct stmp3xxx_runtime_data *prtd = substream->runtime->private_data;
+	int ret = 0;
+
+	switch (cmd) {
+
+	case SNDRV_PCM_TRIGGER_START:
+		stmp3xxx_dma_go(prtd->dma_ch, prtd->dma_desc_array, 1);
+		break;
+
+	case SNDRV_PCM_TRIGGER_STOP:
+		stmp3xxx_pcm_stop(substream);
+		break;
+
+	case SNDRV_PCM_TRIGGER_RESUME:
+	case SNDRV_PCM_TRIGGER_PAUSE_RELEASE:
+		stmp3xxx_dma_unfreeze(prtd->dma_ch);
+		break;
+
+	case SNDRV_PCM_TRIGGER_SUSPEND:
+	case SNDRV_PCM_TRIGGER_PAUSE_PUSH:
+		stmp3xxx_dma_freeze(prtd->dma_ch);
+		break;
+
+	default:
+		ret = -EINVAL;
+		break;
+	}
+
+	return ret;
+}
+
+static snd_pcm_uframes_t
+stmp3xxx_pcm_pointer(struct snd_pcm_substream *substream)
+{
+	struct snd_pcm_runtime *runtime = substream->runtime;
+	struct stmp3xxx_runtime_data *prtd = runtime->private_data;
+	unsigned int offset;
+	dma_addr_t pos;
+
+	pos = __raw_readl(REGS_APBX_BASE +
+			HW_APBX_CHn_BAR(prtd->params->dma_ch));
+	offset = bytes_to_frames(runtime, pos - runtime->dma_addr);
+
+	if (offset >= runtime->buffer_size)
+		offset = 0;
+
+	return offset;
+}
+
+static int stmp3xxx_pcm_hw_params(struct snd_pcm_substream *substream,
+				  struct snd_pcm_hw_params *hw_params)
+{
+	struct stmp3xxx_runtime_data *prtd = substream->runtime->private_data;
+
+	prtd->dma_period = params_period_bytes(hw_params);
+	prtd->dma_totsize = params_buffer_bytes(hw_params);
+
+	return snd_pcm_lib_malloc_pages(substream,
+					params_buffer_bytes(hw_params));
+}
+
+static int stmp3xxx_pcm_hw_free(struct snd_pcm_substream *substream)
+{
+	return snd_pcm_lib_free_pages(substream);
+}
+
+static int stmp3xxx_pcm_dma_request(struct snd_pcm_substream *substream)
+{
+	struct snd_pcm_runtime *runtime = substream->runtime;
+	struct snd_soc_pcm_runtime *rtd = substream->private_data;
+	struct stmp3xxx_runtime_data *prtd = runtime->private_data;
+	struct stmp3xxx_pcm_dma_params *dma_data = rtd->dai->cpu_dai->dma_data;
+	int desc_num = stmp3xxx_pcm_hardware.periods_max;
+	int desc;
+	int ret;
+
+	if (!dma_data)
+		return -ENODEV;
+
+	prtd->params = dma_data;
+	prtd->dma_ch = STMP3XXX_DMA(dma_data->dma_ch, dma_data->dma_bus);
+
+	ret = stmp3xxx_dma_request(prtd->dma_ch, stmp3xxx_pcm_dev,
+				   prtd->params->name);
+	if (ret) {
+		printk(KERN_ERR "%s: Failed to request DMA channel (%d:%d)\n",
+		       __func__, dma_data->dma_bus, dma_data->dma_ch);
+		return ret;
+	}
+
+	/* Allocate memory for data and pio DMA descriptors */
+	prtd->dma_desc_array =
+		kzalloc(sizeof(struct stmp3xxx_dma_descriptor) * desc_num,
+			GFP_KERNEL);
+	if (prtd->dma_desc_array == NULL) {
+		printk(KERN_ERR "%s: Unable to allocate memory\n", __func__);
+		stmp3xxx_dma_release(prtd->dma_ch);
+		return -ENOMEM;
+	}
+
+	for (desc = 0; desc < desc_num; desc++) {
+		ret = stmp3xxx_dma_allocate_command(prtd->dma_ch,
+					    &prtd->dma_desc_array[desc]);
+		if (ret) {
+			printk(KERN_ERR"%s Unable to allocate DMA command %d\n",
+			       __func__, desc);
+			goto err;
+		}
+	}
+
+	ret = request_irq(prtd->params->irq, stmp3xxx_pcm_dma_irq, 0,
+			  "STMP3xxx PCM DMA", substream);
+	if (ret) {
+		printk(KERN_ERR "%s: Unable to request DMA irq %d\n", __func__,
+		       prtd->params->irq);
+		goto err;
+	}
+
+
+	/* Enable completion interrupt */
+	stmp3xxx_dma_clear_interrupt(prtd->dma_ch);
+	stmp3xxx_dma_enable_interrupt(prtd->dma_ch);
+
+	return 0;
+
+err:
+	while (--desc >= 0)
+		stmp3xxx_dma_free_command(prtd->dma_ch,
+					  &prtd->dma_desc_array[desc]);
+	kfree(prtd->dma_desc_array);
+	stmp3xxx_dma_release(prtd->dma_ch);
+
+	return ret;
+}
+
+static int stmp3xxx_pcm_open(struct snd_pcm_substream *substream)
+{
+	struct snd_pcm_runtime *runtime = substream->runtime;
+	struct stmp3xxx_runtime_data *prtd;
+	int ret;
+
+	/* Ensure that buffer size is a multiple of the period size */
+	ret = snd_pcm_hw_constraint_integer(runtime,
+					SNDRV_PCM_HW_PARAM_PERIODS);
+	if (ret < 0)
+		return ret;
+
+	snd_soc_set_runtime_hwparams(substream, &stmp3xxx_pcm_hardware);
+
+	prtd = kzalloc(sizeof(struct stmp3xxx_runtime_data), GFP_KERNEL);
+	if (prtd == NULL)
+		return -ENOMEM;
+
+	runtime->private_data = prtd;
+
+	ret = stmp3xxx_pcm_dma_request(substream);
+	if (ret) {
+		printk(KERN_ERR "stmp3xxx_pcm: Failed to request channels\n");
+		kfree(prtd);
+		return ret;
+	}
+
+	return 0;
+}
+
+static int stmp3xxx_pcm_close(struct snd_pcm_substream *substream)
+{
+	struct snd_pcm_runtime *runtime = substream->runtime;
+	struct stmp3xxx_runtime_data *prtd = runtime->private_data;
+	int desc_num = stmp3xxx_pcm_hardware.periods_max;
+	int desc;
+
+	/* Free DMA irq */
+	free_irq(prtd->params->irq, substream);
+
+	/* Free DMA channel */
+	for (desc = 0; desc < desc_num; desc++)
+		stmp3xxx_dma_free_command(prtd->dma_ch,
+					  &prtd->dma_desc_array[desc]);
+	kfree(prtd->dma_desc_array);
+	stmp3xxx_dma_release(prtd->dma_ch);
+
+	/* Free private runtime data */
+	kfree(prtd);
+
+	return 0;
+}
+
+static int stmp3xxx_pcm_mmap(struct snd_pcm_substream *substream,
+			     struct vm_area_struct *vma)
+{
+	struct snd_pcm_runtime *runtime = substream->runtime;
+
+	return dma_mmap_coherent(NULL, vma, runtime->dma_area,
+				 runtime->dma_addr, runtime->dma_bytes);
+}
+
+struct snd_pcm_ops stmp3xxx_pcm_ops = {
+	.open		= stmp3xxx_pcm_open,
+	.close		= stmp3xxx_pcm_close,
+	.ioctl		= snd_pcm_lib_ioctl,
+	.hw_params	= stmp3xxx_pcm_hw_params,
+	.hw_free	= stmp3xxx_pcm_hw_free,
+	.prepare	= stmp3xxx_pcm_prepare,
+	.trigger	= stmp3xxx_pcm_trigger,
+	.pointer	= stmp3xxx_pcm_pointer,
+	.mmap		= stmp3xxx_pcm_mmap,
+};
+
+static u64 stmp3xxx_pcm_dma_mask = DMA_BIT_MASK(32);
+
+static int stmp3xxx_pcm_new(struct snd_card *card,
+			    struct snd_soc_dai *dai, struct snd_pcm *pcm)
+{
+	size_t size = stmp3xxx_pcm_hardware.buffer_bytes_max;
+
+	if (!card->dev->dma_mask)
+		card->dev->dma_mask = &stmp3xxx_pcm_dma_mask;
+
+	if (!card->dev->coherent_dma_mask)
+		card->dev->coherent_dma_mask = DMA_BIT_MASK(32);
+
+	snd_pcm_lib_preallocate_pages_for_all(pcm, SNDRV_DMA_TYPE_DEV, NULL,
+					      size, size);
+
+	return 0;
+}
+
+static void stmp3xxx_pcm_free(struct snd_pcm *pcm)
+{
+	snd_pcm_lib_preallocate_free_for_all(pcm);
+}
+
+/*
+ * We need probe/remove callbacks to setup stmp3xxx_pcm_dev
+ */
+static int stmp3xxx_pcm_probe(struct platform_device *pdev)
+{
+	stmp3xxx_pcm_dev = &pdev->dev;
+	return 0;
+}
+
+static int stmp3xxx_pcm_remove(struct platform_device *pdev)
+{
+	stmp3xxx_pcm_dev = NULL;
+	return 0;
+}
+
+struct snd_soc_platform stmp3xxx_soc_platform = {
+	.name		= "STMP3xxx Audio",
+	.pcm_ops	= &stmp3xxx_pcm_ops,
+	.probe		= stmp3xxx_pcm_probe,
+	.remove		= stmp3xxx_pcm_remove,
+	.pcm_new	= stmp3xxx_pcm_new,
+	.pcm_free	= stmp3xxx_pcm_free,
+};
+EXPORT_SYMBOL_GPL(stmp3xxx_soc_platform);
+
+static int __init stmp3xxx_pcm_init(void)
+{
+	return snd_soc_register_platform(&stmp3xxx_soc_platform);
+}
+
+static void __exit stmp3xxx_pcm_exit(void)
+{
+	snd_soc_unregister_platform(&stmp3xxx_soc_platform);
+}
+module_init(stmp3xxx_pcm_init);
+module_exit(stmp3xxx_pcm_exit);
+
+MODULE_AUTHOR("Vladislav Buzov");
+MODULE_DESCRIPTION("STMP3xxx DMA Module");
+MODULE_LICENSE("GPL");