// SPDX-License-Identifier: GPL-2.0 // // Serial Sound Interface (I2S) support for SH7760/SH7780 // // Copyright (c) 2007 Manuel Lauss <mano@roarinelk.homelinux.net> // // 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/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_dai *dai) { struct ssi_priv *ssi = &ssi_cpu_data[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_dai *dai) { struct ssi_priv *ssi = &ssi_cpu_data[dai->id]; ssi->inuse = 0; } static int ssi_trigger(struct snd_pcm_substream *substream, int cmd, struct snd_soc_dai *dai) { struct ssi_priv *ssi = &ssi_cpu_data[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_dai *dai) { struct ssi_priv *ssi = &ssi_cpu_data[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: %u channels: %u\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_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_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_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/secondary 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) static const struct snd_soc_dai_ops ssi_dai_ops = { .startup = ssi_startup, .shutdown = ssi_shutdown, .trigger = ssi_trigger, .hw_params = ssi_hw_params, .set_sysclk = ssi_set_sysclk, .set_clkdiv = ssi_set_clkdiv, .set_fmt = ssi_set_fmt, }; static struct snd_soc_dai_driver sh4_ssi_dai[] = { { .name = "ssi-dai.0", .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 = &ssi_dai_ops, }, #ifdef CONFIG_CPU_SUBTYPE_SH7760 { .name = "ssi-dai.1", .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 = &ssi_dai_ops, }, #endif }; static const struct snd_soc_component_driver sh4_ssi_component = { .name = "sh4-ssi", }; static int sh4_soc_dai_probe(struct platform_device *pdev) { return devm_snd_soc_register_component(&pdev->dev, &sh4_ssi_component, sh4_ssi_dai, ARRAY_SIZE(sh4_ssi_dai)); } static struct platform_driver sh4_ssi_driver = { .driver = { .name = "sh4-ssi-dai", }, .probe = sh4_soc_dai_probe, }; module_platform_driver(sh4_ssi_driver); MODULE_LICENSE("GPL v2"); MODULE_DESCRIPTION("SuperH onchip SSI (I2S) audio driver"); MODULE_AUTHOR("Manuel Lauss <mano@roarinelk.homelinux.net>");