--- /dev/null
+/*
+ * Copyright (C) STMicroelectronics SA 2015
+ * Authors: Arnaud Pouliquen <arnaud.pouliquen@st.com>
+ * for STMicroelectronics.
+ * License terms: GNU General Public License (GPL), version 2
+ */
+
+#include <linux/clk.h>
+#include <linux/delay.h>
+#include <linux/io.h>
+
+#include <sound/soc.h>
+
+#include "uniperif.h"
+
+/*
+ * Note: snd_pcm_hardware is linked to DMA controller but is declared here to
+ * integrate unireader capability in term of rate and supported channels
+ */
+const struct snd_pcm_hardware uni_reader_pcm_hw = {
+ .info = SNDRV_PCM_INFO_INTERLEAVED | SNDRV_PCM_INFO_BLOCK_TRANSFER |
+ SNDRV_PCM_INFO_PAUSE | SNDRV_PCM_INFO_MMAP |
+ SNDRV_PCM_INFO_MMAP_VALID,
+ .formats = SNDRV_PCM_FMTBIT_S32_LE | SNDRV_PCM_FMTBIT_S16_LE,
+
+ .rates = SNDRV_PCM_RATE_CONTINUOUS,
+ .rate_min = 8000,
+ .rate_max = 96000,
+
+ .channels_min = 2,
+ .channels_max = 8,
+
+ .periods_min = 2,
+ .periods_max = 48,
+
+ .period_bytes_min = 128,
+ .period_bytes_max = 64 * PAGE_SIZE,
+ .buffer_bytes_max = 256 * PAGE_SIZE
+};
+
+/*
+ * uni_reader_irq_handler
+ * In case of error audio stream is stopped; stop action is protected via PCM
+ * stream lock to avoid race condition with trigger callback.
+ */
+static irqreturn_t uni_reader_irq_handler(int irq, void *dev_id)
+{
+ irqreturn_t ret = IRQ_NONE;
+ struct uniperif *reader = dev_id;
+ unsigned int status;
+
+ if (reader->state == UNIPERIF_STATE_STOPPED) {
+ /* Unexpected IRQ: do nothing */
+ dev_warn(reader->dev, "unexpected IRQ ");
+ return IRQ_HANDLED;
+ }
+
+ /* Get interrupt status & clear them immediately */
+ status = GET_UNIPERIF_ITS(reader);
+ SET_UNIPERIF_ITS_BCLR(reader, status);
+
+ /* Check for fifo overflow error */
+ if (unlikely(status & UNIPERIF_ITS_FIFO_ERROR_MASK(reader))) {
+ dev_err(reader->dev, "FIFO error detected");
+
+ snd_pcm_stream_lock(reader->substream);
+ snd_pcm_stop(reader->substream, SNDRV_PCM_STATE_XRUN);
+ snd_pcm_stream_unlock(reader->substream);
+
+ return IRQ_HANDLED;
+ }
+
+ return ret;
+}
+
+static int uni_reader_prepare(struct snd_pcm_substream *substream,
+ struct snd_soc_dai *dai)
+{
+ struct sti_uniperiph_data *priv = snd_soc_dai_get_drvdata(dai);
+ struct uniperif *reader = priv->dai_data.uni;
+ struct snd_pcm_runtime *runtime = substream->runtime;
+ int transfer_size, trigger_limit;
+ int slot_width;
+ int count = 10;
+
+ /* The reader should be stopped */
+ if (reader->state != UNIPERIF_STATE_STOPPED) {
+ dev_err(reader->dev, "%s: invalid reader state %d", __func__,
+ reader->state);
+ return -EINVAL;
+ }
+
+ /* Calculate transfer size (in fifo cells and bytes) for frame count */
+ transfer_size = runtime->channels * UNIPERIF_FIFO_FRAMES;
+
+ /* Calculate number of empty cells available before asserting DREQ */
+ if (reader->ver < SND_ST_UNIPERIF_VERSION_UNI_PLR_TOP_1_0)
+ trigger_limit = UNIPERIF_FIFO_SIZE - transfer_size;
+ else
+ /*
+ * Since SND_ST_UNIPERIF_VERSION_UNI_PLR_TOP_1_0
+ * FDMA_TRIGGER_LIMIT also controls when the state switches
+ * from OFF or STANDBY to AUDIO DATA.
+ */
+ trigger_limit = transfer_size;
+
+ /* Trigger limit must be an even number */
+ if ((!trigger_limit % 2) ||
+ (trigger_limit != 1 && transfer_size % 2) ||
+ (trigger_limit > UNIPERIF_CONFIG_DMA_TRIG_LIMIT_MASK(reader))) {
+ dev_err(reader->dev, "invalid trigger limit %d", trigger_limit);
+ return -EINVAL;
+ }
+
+ SET_UNIPERIF_CONFIG_DMA_TRIG_LIMIT(reader, trigger_limit);
+
+ switch (reader->daifmt & SND_SOC_DAIFMT_INV_MASK) {
+ case SND_SOC_DAIFMT_IB_IF:
+ case SND_SOC_DAIFMT_NB_IF:
+ SET_UNIPERIF_I2S_FMT_LR_POL_HIG(reader);
+ break;
+ default:
+ SET_UNIPERIF_I2S_FMT_LR_POL_LOW(reader);
+ }
+
+ /* Force slot width to 32 in I2S mode */
+ if ((reader->daifmt & SND_SOC_DAIFMT_FORMAT_MASK)
+ == SND_SOC_DAIFMT_I2S) {
+ slot_width = 32;
+ } else {
+ switch (runtime->format) {
+ case SNDRV_PCM_FORMAT_S16_LE:
+ slot_width = 16;
+ break;
+ default:
+ slot_width = 32;
+ break;
+ }
+ }
+
+ /* Number of bits per subframe (i.e one channel sample) on input. */
+ switch (slot_width) {
+ case 32:
+ SET_UNIPERIF_I2S_FMT_NBIT_32(reader);
+ SET_UNIPERIF_I2S_FMT_DATA_SIZE_32(reader);
+ break;
+ case 16:
+ SET_UNIPERIF_I2S_FMT_NBIT_16(reader);
+ SET_UNIPERIF_I2S_FMT_DATA_SIZE_16(reader);
+ break;
+ default:
+ dev_err(reader->dev, "subframe format not supported");
+ return -EINVAL;
+ }
+
+ /* Configure data memory format */
+ switch (runtime->format) {
+ case SNDRV_PCM_FORMAT_S16_LE:
+ /* One data word contains two samples */
+ SET_UNIPERIF_CONFIG_MEM_FMT_16_16(reader);
+ break;
+
+ case SNDRV_PCM_FORMAT_S32_LE:
+ /*
+ * Actually "16 bits/0 bits" means "32/28/24/20/18/16 bits
+ * on the MSB then zeros (if less than 32 bytes)"...
+ */
+ SET_UNIPERIF_CONFIG_MEM_FMT_16_0(reader);
+ break;
+
+ default:
+ dev_err(reader->dev, "format not supported");
+ return -EINVAL;
+ }
+
+ switch (reader->daifmt & SND_SOC_DAIFMT_FORMAT_MASK) {
+ case SND_SOC_DAIFMT_I2S:
+ SET_UNIPERIF_I2S_FMT_ALIGN_LEFT(reader);
+ SET_UNIPERIF_I2S_FMT_PADDING_I2S_MODE(reader);
+ break;
+ case SND_SOC_DAIFMT_LEFT_J:
+ SET_UNIPERIF_I2S_FMT_ALIGN_LEFT(reader);
+ SET_UNIPERIF_I2S_FMT_PADDING_SONY_MODE(reader);
+ break;
+ case SND_SOC_DAIFMT_RIGHT_J:
+ SET_UNIPERIF_I2S_FMT_ALIGN_RIGHT(reader);
+ SET_UNIPERIF_I2S_FMT_PADDING_SONY_MODE(reader);
+ break;
+ default:
+ dev_err(reader->dev, "format not supported");
+ return -EINVAL;
+ }
+
+ SET_UNIPERIF_I2S_FMT_ORDER_MSB(reader);
+
+ /* Data clocking (changing) on the rising edge */
+ SET_UNIPERIF_I2S_FMT_SCLK_EDGE_RISING(reader);
+
+ /* Number of channels must be even */
+
+ if ((runtime->channels % 2) || (runtime->channels < 2) ||
+ (runtime->channels > 10)) {
+ dev_err(reader->dev, "%s: invalid nb of channels", __func__);
+ return -EINVAL;
+ }
+
+ SET_UNIPERIF_I2S_FMT_NUM_CH(reader, runtime->channels / 2);
+
+ /* Clear any pending interrupts */
+ SET_UNIPERIF_ITS_BCLR(reader, GET_UNIPERIF_ITS(reader));
+
+ SET_UNIPERIF_I2S_FMT_NO_OF_SAMPLES_TO_READ(reader, 0);
+
+ /* Set the interrupt mask */
+ SET_UNIPERIF_ITM_BSET_DMA_ERROR(reader);
+ SET_UNIPERIF_ITM_BSET_FIFO_ERROR(reader);
+ SET_UNIPERIF_ITM_BSET_MEM_BLK_READ(reader);
+
+ /* Enable underflow recovery interrupts */
+ if (reader->info->underflow_enabled) {
+ SET_UNIPERIF_ITM_BSET_UNDERFLOW_REC_DONE(reader);
+ SET_UNIPERIF_ITM_BSET_UNDERFLOW_REC_FAILED(reader);
+ }
+
+ /* Reset uniperipheral reader */
+ SET_UNIPERIF_SOFT_RST_SOFT_RST(reader);
+
+ while (GET_UNIPERIF_SOFT_RST_SOFT_RST(reader)) {
+ udelay(5);
+ count--;
+ }
+ if (!count) {
+ dev_err(reader->dev, "Failed to reset uniperif");
+ return -EIO;
+ }
+
+ return 0;
+}
+
+static int uni_reader_start(struct uniperif *reader)
+{
+ /* The reader should be stopped */
+ if (reader->state != UNIPERIF_STATE_STOPPED) {
+ dev_err(reader->dev, "%s: invalid reader state", __func__);
+ return -EINVAL;
+ }
+
+ /* Enable reader interrupts (and clear possible stalled ones) */
+ SET_UNIPERIF_ITS_BCLR_FIFO_ERROR(reader);
+ SET_UNIPERIF_ITM_BSET_FIFO_ERROR(reader);
+
+ /* Launch the reader */
+ SET_UNIPERIF_CTRL_OPERATION_PCM_DATA(reader);
+
+ /* Update state to started */
+ reader->state = UNIPERIF_STATE_STARTED;
+ return 0;
+}
+
+static int uni_reader_stop(struct uniperif *reader)
+{
+ /* The reader should not be in stopped state */
+ if (reader->state == UNIPERIF_STATE_STOPPED) {
+ dev_err(reader->dev, "%s: invalid reader state", __func__);
+ return -EINVAL;
+ }
+
+ /* Turn the reader off */
+ SET_UNIPERIF_CTRL_OPERATION_OFF(reader);
+
+ /* Disable interrupts */
+ SET_UNIPERIF_ITM_BCLR(reader, GET_UNIPERIF_ITM(reader));
+
+ /* Update state to stopped and return */
+ reader->state = UNIPERIF_STATE_STOPPED;
+
+ return 0;
+}
+
+static int uni_reader_trigger(struct snd_pcm_substream *substream,
+ int cmd, struct snd_soc_dai *dai)
+{
+ struct sti_uniperiph_data *priv = snd_soc_dai_get_drvdata(dai);
+ struct uniperif *reader = priv->dai_data.uni;
+
+ switch (cmd) {
+ case SNDRV_PCM_TRIGGER_START:
+ return uni_reader_start(reader);
+ case SNDRV_PCM_TRIGGER_STOP:
+ return uni_reader_stop(reader);
+ default:
+ return -EINVAL;
+ }
+}
+
+static void uni_reader_shutdown(struct snd_pcm_substream *substream,
+ struct snd_soc_dai *dai)
+{
+ struct sti_uniperiph_data *priv = snd_soc_dai_get_drvdata(dai);
+ struct uniperif *reader = priv->dai_data.uni;
+
+ if (reader->state != UNIPERIF_STATE_STOPPED) {
+ /* Stop the reader */
+ uni_reader_stop(reader);
+ }
+}
+
+static int uni_reader_parse_dt(struct platform_device *pdev,
+ struct uniperif *reader)
+{
+ struct uniperif_info *info;
+ struct device_node *node = pdev->dev.of_node;
+
+ /* Allocate memory for the info structure */
+ info = devm_kzalloc(&pdev->dev, sizeof(*info), GFP_KERNEL);
+ if (!info)
+ return -ENOMEM;
+
+ of_property_read_u32(node, "version", &reader->ver);
+
+ /* Save the info structure */
+ reader->info = info;
+
+ return 0;
+}
+
+const struct snd_soc_dai_ops uni_reader_dai_ops = {
+ .shutdown = uni_reader_shutdown,
+ .prepare = uni_reader_prepare,
+ .trigger = uni_reader_trigger,
+ .hw_params = sti_uniperiph_dai_hw_params,
+ .set_fmt = sti_uniperiph_dai_set_fmt,
+};
+
+int uni_reader_init(struct platform_device *pdev,
+ struct uniperif *reader)
+{
+ int ret = 0;
+
+ reader->dev = &pdev->dev;
+ reader->state = UNIPERIF_STATE_STOPPED;
+ reader->hw = &uni_reader_pcm_hw;
+ reader->dai_ops = &uni_reader_dai_ops;
+
+ dev_err(reader->dev, "%s: enter\n", __func__);
+ ret = uni_reader_parse_dt(pdev, reader);
+ if (ret < 0) {
+ dev_err(reader->dev, "Failed to parse DeviceTree");
+ return ret;
+ }
+
+ ret = devm_request_irq(&pdev->dev, reader->irq,
+ uni_reader_irq_handler, IRQF_SHARED,
+ dev_name(&pdev->dev), reader);
+ if (ret < 0) {
+ dev_err(&pdev->dev, "Failed to request IRQ");
+ return -EBUSY;
+ }
+
+ return 0;
+}
+EXPORT_SYMBOL_GPL(uni_reader_init);