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-rw-r--r--sound/soc/sh/ssi.c400
1 files changed, 400 insertions, 0 deletions
diff --git a/sound/soc/sh/ssi.c b/sound/soc/sh/ssi.c
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+++ b/sound/soc/sh/ssi.c
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+/*
+ * Serial Sound Interface (I2S) support for SH7760/SH7780
+ *
+ * Copyright (c) 2007 Manuel Lauss <mano@roarinelk.homelinux.net>
+ *
+ * licensed under the terms outlined in the file COPYING at the root
+ * of the linux kernel sources.
+ *
+ * dont forget to set IPSEL/OMSEL register bits (in your board code) to
+ * enable SSI output pins!
+ */
+
+/*
+ * LIMITATIONS:
+ * The SSI unit has only one physical data line, so full duplex is
+ * impossible. This can be remedied on the SH7760 by using the
+ * other SSI unit for recording; however the SH7780 has only 1 SSI
+ * unit, and its pins are shared with the AC97 unit, among others.
+ *
+ * FEATURES:
+ * The SSI features "compressed mode": in this mode it continuously
+ * streams PCM data over the I2S lines and uses LRCK as a handshake
+ * signal. Can be used to send compressed data (AC3/DTS) to a DSP.
+ * The number of bits sent over the wire in a frame can be adjusted
+ * and can be independent from the actual sample bit depth. This is
+ * useful to support TDM mode codecs like the AD1939 which have a
+ * fixed TDM slot size, regardless of sample resolution.
+ */
+
+#include <linux/init.h>
+#include <linux/module.h>
+#include <linux/platform_device.h>
+#include <sound/driver.h>
+#include <sound/core.h>
+#include <sound/pcm.h>
+#include <sound/initval.h>
+#include <sound/soc.h>
+#include <asm/io.h>
+
+#define SSICR 0x00
+#define SSISR 0x04
+
+#define CR_DMAEN (1 << 28)
+#define CR_CHNL_SHIFT 22
+#define CR_CHNL_MASK (3 << CR_CHNL_SHIFT)
+#define CR_DWL_SHIFT 19
+#define CR_DWL_MASK (7 << CR_DWL_SHIFT)
+#define CR_SWL_SHIFT 16
+#define CR_SWL_MASK (7 << CR_SWL_SHIFT)
+#define CR_SCK_MASTER (1 << 15) /* bitclock master bit */
+#define CR_SWS_MASTER (1 << 14) /* wordselect master bit */
+#define CR_SCKP (1 << 13) /* I2Sclock polarity */
+#define CR_SWSP (1 << 12) /* LRCK polarity */
+#define CR_SPDP (1 << 11)
+#define CR_SDTA (1 << 10) /* i2s alignment (msb/lsb) */
+#define CR_PDTA (1 << 9) /* fifo data alignment */
+#define CR_DEL (1 << 8) /* delay data by 1 i2sclk */
+#define CR_BREN (1 << 7) /* clock gating in burst mode */
+#define CR_CKDIV_SHIFT 4
+#define CR_CKDIV_MASK (7 << CR_CKDIV_SHIFT) /* bitclock divider */
+#define CR_MUTE (1 << 3) /* SSI mute */
+#define CR_CPEN (1 << 2) /* compressed mode */
+#define CR_TRMD (1 << 1) /* transmit/receive select */
+#define CR_EN (1 << 0) /* enable SSI */
+
+#define SSIREG(reg) (*(unsigned long *)(ssi->mmio + (reg)))
+
+struct ssi_priv {
+ unsigned long mmio;
+ unsigned long sysclk;
+ int inuse;
+} ssi_cpu_data[] = {
+#if defined(CONFIG_CPU_SUBTYPE_SH7760)
+ {
+ .mmio = 0xFE680000,
+ },
+ {
+ .mmio = 0xFE690000,
+ },
+#elif defined(CONFIG_CPU_SUBTYPE_SH7780)
+ {
+ .mmio = 0xFFE70000,
+ },
+#else
+#error "Unsupported SuperH SoC"
+#endif
+};
+
+/*
+ * track usage of the SSI; it is simplex-only so prevent attempts of
+ * concurrent playback + capture. FIXME: any locking required?
+ */
+static int ssi_startup(struct snd_pcm_substream *substream)
+{
+ struct snd_soc_pcm_runtime *rtd = substream->private_data;
+ struct ssi_priv *ssi = &ssi_cpu_data[rtd->dai->cpu_dai->id];
+ if (ssi->inuse) {
+ pr_debug("ssi: already in use!\n");
+ return -EBUSY;
+ } else
+ ssi->inuse = 1;
+ return 0;
+}
+
+static void ssi_shutdown(struct snd_pcm_substream *substream)
+{
+ struct snd_soc_pcm_runtime *rtd = substream->private_data;
+ struct ssi_priv *ssi = &ssi_cpu_data[rtd->dai->cpu_dai->id];
+
+ ssi->inuse = 0;
+}
+
+static int ssi_trigger(struct snd_pcm_substream *substream, int cmd)
+{
+ struct snd_soc_pcm_runtime *rtd = substream->private_data;
+ struct ssi_priv *ssi = &ssi_cpu_data[rtd->dai->cpu_dai->id];
+
+ switch (cmd) {
+ case SNDRV_PCM_TRIGGER_START:
+ SSIREG(SSICR) |= CR_DMAEN | CR_EN;
+ break;
+ case SNDRV_PCM_TRIGGER_STOP:
+ SSIREG(SSICR) &= ~(CR_DMAEN | CR_EN);
+ break;
+ default:
+ return -EINVAL;
+ }
+
+ return 0;
+}
+
+static int ssi_hw_params(struct snd_pcm_substream *substream,
+ struct snd_pcm_hw_params *params)
+{
+ struct snd_soc_pcm_runtime *rtd = substream->private_data;
+ struct ssi_priv *ssi = &ssi_cpu_data[rtd->dai->cpu_dai->id];
+ unsigned long ssicr = SSIREG(SSICR);
+ unsigned int bits, channels, swl, recv, i;
+
+ channels = params_channels(params);
+ bits = params->msbits;
+ recv = (substream->stream == SNDRV_PCM_STREAM_PLAYBACK) ? 0 : 1;
+
+ pr_debug("ssi_hw_params() enter\nssicr was %08lx\n", ssicr);
+ pr_debug("bits: %d channels: %d\n", bits, channels);
+
+ ssicr &= ~(CR_TRMD | CR_CHNL_MASK | CR_DWL_MASK | CR_PDTA |
+ CR_SWL_MASK);
+
+ /* direction (send/receive) */
+ if (!recv)
+ ssicr |= CR_TRMD; /* transmit */
+
+ /* channels */
+ if ((channels < 2) || (channels > 8) || (channels & 1)) {
+ pr_debug("ssi: invalid number of channels\n");
+ return -EINVAL;
+ }
+ ssicr |= ((channels >> 1) - 1) << CR_CHNL_SHIFT;
+
+ /* DATA WORD LENGTH (DWL): databits in audio sample */
+ i = 0;
+ switch (bits) {
+ case 32: ++i;
+ case 24: ++i;
+ case 22: ++i;
+ case 20: ++i;
+ case 18: ++i;
+ case 16: ++i;
+ ssicr |= i << CR_DWL_SHIFT;
+ case 8: break;
+ default:
+ pr_debug("ssi: invalid sample width\n");
+ return -EINVAL;
+ }
+
+ /*
+ * SYSTEM WORD LENGTH: size in bits of half a frame over the I2S
+ * wires. This is usually bits_per_sample x channels/2; i.e. in
+ * Stereo mode the SWL equals DWL. SWL can be bigger than the
+ * product of (channels_per_slot x samplebits), e.g. for codecs
+ * like the AD1939 which only accept 32bit wide TDM slots. For
+ * "standard" I2S operation we set SWL = chans / 2 * DWL here.
+ * Waiting for ASoC to get TDM support ;-)
+ */
+ if ((bits > 16) && (bits <= 24)) {
+ bits = 24; /* these are padded by the SSI */
+ /*ssicr |= CR_PDTA;*/ /* cpu/data endianness ? */
+ }
+ i = 0;
+ swl = (bits * channels) / 2;
+ switch (swl) {
+ case 256: ++i;
+ case 128: ++i;
+ case 64: ++i;
+ case 48: ++i;
+ case 32: ++i;
+ case 16: ++i;
+ ssicr |= i << CR_SWL_SHIFT;
+ case 8: break;
+ default:
+ pr_debug("ssi: invalid system word length computed\n");
+ return -EINVAL;
+ }
+
+ SSIREG(SSICR) = ssicr;
+
+ pr_debug("ssi_hw_params() leave\nssicr is now %08lx\n", ssicr);
+ return 0;
+}
+
+static int ssi_set_sysclk(struct snd_soc_cpu_dai *cpu_dai, int clk_id,
+ unsigned int freq, int dir)
+{
+ struct ssi_priv *ssi = &ssi_cpu_data[cpu_dai->id];
+
+ ssi->sysclk = freq;
+
+ return 0;
+}
+
+/*
+ * This divider is used to generate the SSI_SCK (I2S bitclock) from the
+ * clock at the HAC_BIT_CLK ("oversampling clock") pin.
+ */
+static int ssi_set_clkdiv(struct snd_soc_cpu_dai *dai, int did, int div)
+{
+ struct ssi_priv *ssi = &ssi_cpu_data[dai->id];
+ unsigned long ssicr;
+ int i;
+
+ i = 0;
+ ssicr = SSIREG(SSICR) & ~CR_CKDIV_MASK;
+ switch (div) {
+ case 16: ++i;
+ case 8: ++i;
+ case 4: ++i;
+ case 2: ++i;
+ SSIREG(SSICR) = ssicr | (i << CR_CKDIV_SHIFT);
+ case 1: break;
+ default:
+ pr_debug("ssi: invalid sck divider %d\n", div);
+ return -EINVAL;
+ }
+
+ return 0;
+}
+
+static int ssi_set_fmt(struct snd_soc_cpu_dai *dai, unsigned int fmt)
+{
+ struct ssi_priv *ssi = &ssi_cpu_data[dai->id];
+ unsigned long ssicr = SSIREG(SSICR);
+
+ pr_debug("ssi_set_fmt()\nssicr was 0x%08lx\n", ssicr);
+
+ ssicr &= ~(CR_DEL | CR_PDTA | CR_BREN | CR_SWSP | CR_SCKP |
+ CR_SWS_MASTER | CR_SCK_MASTER);
+
+ switch (fmt & SND_SOC_DAIFMT_FORMAT_MASK) {
+ case SND_SOC_DAIFMT_I2S:
+ break;
+ case SND_SOC_DAIFMT_RIGHT_J:
+ ssicr |= CR_DEL | CR_PDTA;
+ break;
+ case SND_SOC_DAIFMT_LEFT_J:
+ ssicr |= CR_DEL;
+ break;
+ default:
+ pr_debug("ssi: unsupported format\n");
+ return -EINVAL;
+ }
+
+ switch (fmt & SND_SOC_DAIFMT_CLOCK_MASK) {
+ case SND_SOC_DAIFMT_CONT:
+ break;
+ case SND_SOC_DAIFMT_GATED:
+ ssicr |= CR_BREN;
+ break;
+ }
+
+ switch (fmt & SND_SOC_DAIFMT_INV_MASK) {
+ case SND_SOC_DAIFMT_NB_NF:
+ ssicr |= CR_SCKP; /* sample data at low clkedge */
+ break;
+ case SND_SOC_DAIFMT_NB_IF:
+ ssicr |= CR_SCKP | CR_SWSP;
+ break;
+ case SND_SOC_DAIFMT_IB_NF:
+ break;
+ case SND_SOC_DAIFMT_IB_IF:
+ ssicr |= CR_SWSP; /* word select starts low */
+ break;
+ default:
+ pr_debug("ssi: invalid inversion\n");
+ return -EINVAL;
+ }
+
+ switch (fmt & SND_SOC_DAIFMT_MASTER_MASK) {
+ case SND_SOC_DAIFMT_CBM_CFM:
+ break;
+ case SND_SOC_DAIFMT_CBS_CFM:
+ ssicr |= CR_SCK_MASTER;
+ break;
+ case SND_SOC_DAIFMT_CBM_CFS:
+ ssicr |= CR_SWS_MASTER;
+ break;
+ case SND_SOC_DAIFMT_CBS_CFS:
+ ssicr |= CR_SWS_MASTER | CR_SCK_MASTER;
+ break;
+ default:
+ pr_debug("ssi: invalid master/slave configuration\n");
+ return -EINVAL;
+ }
+
+ SSIREG(SSICR) = ssicr;
+ pr_debug("ssi_set_fmt() leave\nssicr is now 0x%08lx\n", ssicr);
+
+ return 0;
+}
+
+/* the SSI depends on an external clocksource (at HAC_BIT_CLK) even in
+ * Master mode, so really this is board specific; the SSI can do any
+ * rate with the right bitclk and divider settings.
+ */
+#define SSI_RATES \
+ SNDRV_PCM_RATE_8000_192000
+
+/* the SSI can do 8-32 bit samples, with 8 possible channels */
+#define SSI_FMTS \
+ (SNDRV_PCM_FMTBIT_S8 | SNDRV_PCM_FMTBIT_U8 | \
+ SNDRV_PCM_FMTBIT_S16_LE | SNDRV_PCM_FMTBIT_U16_LE | \
+ SNDRV_PCM_FMTBIT_S20_3LE | SNDRV_PCM_FMTBIT_U20_3LE | \
+ SNDRV_PCM_FMTBIT_S24_3LE | SNDRV_PCM_FMTBIT_U24_3LE | \
+ SNDRV_PCM_FMTBIT_S32_LE | SNDRV_PCM_FMTBIT_U32_LE)
+
+struct snd_soc_cpu_dai sh4_ssi_dai[] = {
+{
+ .name = "SSI0",
+ .id = 0,
+ .type = SND_SOC_DAI_I2S,
+ .playback = {
+ .rates = SSI_RATES,
+ .formats = SSI_FMTS,
+ .channels_min = 2,
+ .channels_max = 8,
+ },
+ .capture = {
+ .rates = SSI_RATES,
+ .formats = SSI_FMTS,
+ .channels_min = 2,
+ .channels_max = 8,
+ },
+ .ops = {
+ .startup = ssi_startup,
+ .shutdown = ssi_shutdown,
+ .trigger = ssi_trigger,
+ .hw_params = ssi_hw_params,
+ },
+ .dai_ops = {
+ .set_sysclk = ssi_set_sysclk,
+ .set_clkdiv = ssi_set_clkdiv,
+ .set_fmt = ssi_set_fmt,
+ },
+},
+#ifdef CONFIG_CPU_SUBTYPE_SH7760
+{
+ .name = "SSI1",
+ .id = 1,
+ .type = SND_SOC_DAI_I2S,
+ .playback = {
+ .rates = SSI_RATES,
+ .formats = SSI_FMTS,
+ .channels_min = 2,
+ .channels_max = 8,
+ },
+ .capture = {
+ .rates = SSI_RATES,
+ .formats = SSI_FMTS,
+ .channels_min = 2,
+ .channels_max = 8,
+ },
+ .ops = {
+ .startup = ssi_startup,
+ .shutdown = ssi_shutdown,
+ .trigger = ssi_trigger,
+ .hw_params = ssi_hw_params,
+ },
+ .dai_ops = {
+ .set_sysclk = ssi_set_sysclk,
+ .set_clkdiv = ssi_set_clkdiv,
+ .set_fmt = ssi_set_fmt,
+ },
+},
+#endif
+};
+EXPORT_SYMBOL_GPL(sh4_ssi_dai);
+
+MODULE_LICENSE("GPL");
+MODULE_DESCRIPTION("SuperH onchip SSI (I2S) audio driver");
+MODULE_AUTHOR("Manuel Lauss <mano@roarinelk.homelinux.net>");
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