From 838d1631b766529213684f07dd71cdf2e92f0623 Mon Sep 17 00:00:00 2001 From: Russell King Date: Sat, 9 May 2015 11:26:42 +0100 Subject: ALSA: pcm: add DRM ELD helper Add a helper for the EDID like data structure, which is typically passed from a HDMI adapter to its associated audio driver. This informs the audio driver of the capabilities of the attached HDMI sink. Signed-off-by: Russell King Reviewed-by: Mark Brown Signed-off-by: Takashi Iwai --- sound/core/Kconfig | 3 ++ sound/core/Makefile | 1 + sound/core/pcm_drm_eld.c | 99 ++++++++++++++++++++++++++++++++++++++++++++++++ 3 files changed, 103 insertions(+) create mode 100644 sound/core/pcm_drm_eld.c (limited to 'sound/core') diff --git a/sound/core/Kconfig b/sound/core/Kconfig index 313f22e9d929..b534c8a6046b 100644 --- a/sound/core/Kconfig +++ b/sound/core/Kconfig @@ -6,6 +6,9 @@ config SND_PCM tristate select SND_TIMER +config SND_PCM_ELD + bool + config SND_DMAENGINE_PCM tristate diff --git a/sound/core/Makefile b/sound/core/Makefile index 4daf2f58261c..591b49157b4d 100644 --- a/sound/core/Makefile +++ b/sound/core/Makefile @@ -13,6 +13,7 @@ snd-$(CONFIG_SND_JACK) += jack.o snd-pcm-y := pcm.o pcm_native.o pcm_lib.o pcm_timer.o pcm_misc.o \ pcm_memory.o memalloc.o snd-pcm-$(CONFIG_SND_DMA_SGBUF) += sgbuf.o +snd-pcm-$(CONFIG_SND_PCM_ELD) += pcm_drm_eld.o # for trace-points CFLAGS_pcm_lib.o := -I$(src) diff --git a/sound/core/pcm_drm_eld.c b/sound/core/pcm_drm_eld.c new file mode 100644 index 000000000000..e70379fb63d0 --- /dev/null +++ b/sound/core/pcm_drm_eld.c @@ -0,0 +1,99 @@ +/* + * PCM DRM helpers + * + * 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 +#include +#include +#include + +static const unsigned int eld_rates[] = { + 32000, + 44100, + 48000, + 88200, + 96000, + 176400, + 192000, +}; + +static unsigned int sad_max_channels(const u8 *sad) +{ + return 1 + (sad[0] & 7); +} + +static int eld_limit_rates(struct snd_pcm_hw_params *params, + struct snd_pcm_hw_rule *rule) +{ + struct snd_interval *r = hw_param_interval(params, rule->var); + struct snd_interval *c; + unsigned int rate_mask = 7, i; + const u8 *sad, *eld = rule->private; + + sad = drm_eld_sad(eld); + if (sad) { + c = hw_param_interval(params, SNDRV_PCM_HW_PARAM_CHANNELS); + + for (i = drm_eld_sad_count(eld); i > 0; i--, sad += 3) { + unsigned max_channels = sad_max_channels(sad); + + /* + * Exclude SADs which do not include the + * requested number of channels. + */ + if (c->min <= max_channels) + rate_mask |= sad[1]; + } + } + + return snd_interval_list(r, ARRAY_SIZE(eld_rates), eld_rates, + rate_mask); +} + +static int eld_limit_channels(struct snd_pcm_hw_params *params, + struct snd_pcm_hw_rule *rule) +{ + struct snd_interval *c = hw_param_interval(params, rule->var); + struct snd_interval *r; + struct snd_interval t = { .min = 1, .max = 2, .integer = 1, }; + unsigned int i; + const u8 *sad, *eld = rule->private; + + sad = drm_eld_sad(eld); + if (sad) { + unsigned int rate_mask = 0; + + /* Convert the rate interval to a mask */ + r = hw_param_interval(params, SNDRV_PCM_HW_PARAM_RATE); + for (i = 0; i < ARRAY_SIZE(eld_rates); i++) + if (r->min <= eld_rates[i] && r->max >= eld_rates[i]) + rate_mask |= BIT(i); + + for (i = drm_eld_sad_count(eld); i > 0; i--, sad += 3) + if (rate_mask & sad[1]) + t.max = max(t.max, sad_max_channels(sad)); + } + + return snd_interval_refine(c, &t); +} + +int snd_pcm_hw_constraint_eld(struct snd_pcm_runtime *runtime, void *eld) +{ + int ret; + + ret = snd_pcm_hw_rule_add(runtime, 0, SNDRV_PCM_HW_PARAM_RATE, + eld_limit_rates, eld, + SNDRV_PCM_HW_PARAM_CHANNELS, -1); + if (ret < 0) + return ret; + + ret = snd_pcm_hw_rule_add(runtime, 0, SNDRV_PCM_HW_PARAM_CHANNELS, + eld_limit_channels, eld, + SNDRV_PCM_HW_PARAM_RATE, -1); + + return ret; +} +EXPORT_SYMBOL_GPL(snd_pcm_hw_constraint_eld); -- cgit From 9203dd016a5d8ffb2eb6acdca60cd0b5dfe38c2b Mon Sep 17 00:00:00 2001 From: Russell King Date: Sat, 9 May 2015 11:26:47 +0100 Subject: ALSA: pcm: add IEC958 channel status helper Add a helper to create the IEC958 channel status from an ALSA snd_pcm_runtime structure, taking account of the sample rate and sample size. Signed-off-by: Russell King Reviwed-by: Mark Brown Signed-off-by: Takashi Iwai --- sound/core/Kconfig | 3 ++ sound/core/Makefile | 1 + sound/core/pcm_iec958.c | 95 +++++++++++++++++++++++++++++++++++++++++++++++++ 3 files changed, 99 insertions(+) create mode 100644 sound/core/pcm_iec958.c (limited to 'sound/core') diff --git a/sound/core/Kconfig b/sound/core/Kconfig index b534c8a6046b..1507469425ec 100644 --- a/sound/core/Kconfig +++ b/sound/core/Kconfig @@ -9,6 +9,9 @@ config SND_PCM config SND_PCM_ELD bool +config SND_PCM_IEC958 + bool + config SND_DMAENGINE_PCM tristate diff --git a/sound/core/Makefile b/sound/core/Makefile index 591b49157b4d..2b925fcc95ea 100644 --- a/sound/core/Makefile +++ b/sound/core/Makefile @@ -14,6 +14,7 @@ snd-pcm-y := pcm.o pcm_native.o pcm_lib.o pcm_timer.o pcm_misc.o \ pcm_memory.o memalloc.o snd-pcm-$(CONFIG_SND_DMA_SGBUF) += sgbuf.o snd-pcm-$(CONFIG_SND_PCM_ELD) += pcm_drm_eld.o +snd-pcm-$(CONFIG_SND_PCM_IEC958) += pcm_iec958.o # for trace-points CFLAGS_pcm_lib.o := -I$(src) diff --git a/sound/core/pcm_iec958.c b/sound/core/pcm_iec958.c new file mode 100644 index 000000000000..36b2d7aca1bd --- /dev/null +++ b/sound/core/pcm_iec958.c @@ -0,0 +1,95 @@ +/* + * PCM DRM helpers + * + * 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 +#include +#include +#include +#include + +/** + * snd_pcm_create_iec958_consumer - create consumer format IEC958 channel status + * @runtime: pcm runtime structure with ->rate filled in + * @cs: channel status buffer, at least four bytes + * @len: length of channel status buffer + * + * Create the consumer format channel status data in @cs of maximum size + * @len corresponding to the parameters of the PCM runtime @runtime. + * + * Drivers may wish to tweak the contents of the buffer after creation. + * + * Returns: length of buffer, or negative error code if something failed. + */ +int snd_pcm_create_iec958_consumer(struct snd_pcm_runtime *runtime, u8 *cs, + size_t len) +{ + unsigned int fs, ws; + + if (len < 4) + return -EINVAL; + + switch (runtime->rate) { + case 32000: + fs = IEC958_AES3_CON_FS_32000; + break; + case 44100: + fs = IEC958_AES3_CON_FS_44100; + break; + case 48000: + fs = IEC958_AES3_CON_FS_48000; + break; + case 88200: + fs = IEC958_AES3_CON_FS_88200; + break; + case 96000: + fs = IEC958_AES3_CON_FS_96000; + break; + case 176400: + fs = IEC958_AES3_CON_FS_176400; + break; + case 192000: + fs = IEC958_AES3_CON_FS_192000; + break; + default: + return -EINVAL; + } + + if (len > 4) { + switch (snd_pcm_format_width(runtime->format)) { + case 16: + ws = IEC958_AES4_CON_WORDLEN_20_16; + break; + case 18: + ws = IEC958_AES4_CON_WORDLEN_22_18; + break; + case 20: + ws = IEC958_AES4_CON_WORDLEN_20_16 | + IEC958_AES4_CON_MAX_WORDLEN_24; + break; + case 24: + ws = IEC958_AES4_CON_WORDLEN_24_20 | + IEC958_AES4_CON_MAX_WORDLEN_24; + break; + + default: + return -EINVAL; + } + } + + memset(cs, 0, len); + + cs[0] = IEC958_AES0_CON_NOT_COPYRIGHT | IEC958_AES0_CON_EMPHASIS_NONE; + cs[1] = IEC958_AES1_CON_GENERAL; + cs[2] = IEC958_AES2_CON_SOURCE_UNSPEC | IEC958_AES2_CON_CHANNEL_UNSPEC; + cs[3] = IEC958_AES3_CON_CLOCK_1000PPM | fs; + + if (len > 4) + cs[4] = ws; + + return len; +} +EXPORT_SYMBOL(snd_pcm_create_iec958_consumer); -- cgit