diff options
Diffstat (limited to 'sound/core/pcm_iec958.c')
| -rw-r--r-- | sound/core/pcm_iec958.c | 174 |
1 files changed, 132 insertions, 42 deletions
diff --git a/sound/core/pcm_iec958.c b/sound/core/pcm_iec958.c index f9a211cc1f2c..7a1b816f67cc 100644 --- a/sound/core/pcm_iec958.c +++ b/sound/core/pcm_iec958.c @@ -9,41 +9,85 @@ #include <sound/pcm_params.h> #include <sound/pcm_iec958.h> -static int create_iec958_consumer(uint rate, uint sample_width, - u8 *cs, size_t len) +/** + * snd_pcm_create_iec958_consumer_default - create default consumer format IEC958 channel status + * @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. When relevant, the configuration-dependant bits will be set as + * unspecified. + * + * Drivers should then call einter snd_pcm_fill_iec958_consumer() or + * snd_pcm_fill_iec958_consumer_hw_params() to replace these unspecified + * bits by their actual values. + * + * 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_default(u8 *cs, size_t len) { - unsigned int fs, ws; - if (len < 4) return -EINVAL; - switch (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: + 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 | IEC958_AES3_CON_FS_NOTID; + + if (len > 4) + cs[4] = IEC958_AES4_CON_WORDLEN_NOTID; + + return len; +} +EXPORT_SYMBOL_GPL(snd_pcm_create_iec958_consumer_default); + +static int fill_iec958_consumer(uint rate, uint sample_width, + u8 *cs, size_t len) +{ + if (len < 4) return -EINVAL; + + if ((cs[3] & IEC958_AES3_CON_FS) == IEC958_AES3_CON_FS_NOTID) { + unsigned int fs; + + switch (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; + } + + cs[3] &= ~IEC958_AES3_CON_FS; + cs[3] |= fs; } - if (len > 4) { + if (len > 4 && + (cs[4] & IEC958_AES4_CON_WORDLEN) == IEC958_AES4_CON_WORDLEN_NOTID) { + unsigned int ws; + switch (sample_width) { case 16: ws = IEC958_AES4_CON_WORDLEN_20_16; @@ -64,20 +108,57 @@ static int create_iec958_consumer(uint rate, uint sample_width, default: return -EINVAL; } - } - memset(cs, 0, len); + cs[4] &= ~IEC958_AES4_CON_WORDLEN; + cs[4] |= ws; + } - 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; + return len; +} - if (len > 4) - cs[4] = ws; +/** + * snd_pcm_fill_iec958_consumer - Fill 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 + * + * Fill the unspecified bits in an IEC958 status bits array using the + * parameters of the PCM runtime @runtime. + * + * Drivers may wish to tweak the contents of the buffer after its been + * filled. + * + * Returns: length of buffer, or negative error code if something failed. + */ +int snd_pcm_fill_iec958_consumer(struct snd_pcm_runtime *runtime, + u8 *cs, size_t len) +{ + return fill_iec958_consumer(runtime->rate, + snd_pcm_format_width(runtime->format), + cs, len); +} +EXPORT_SYMBOL_GPL(snd_pcm_fill_iec958_consumer); - return len; +/** + * snd_pcm_fill_iec958_consumer_hw_params - Fill consumer format IEC958 channel status + * @params: the hw_params instance for extracting rate and sample format + * @cs: channel status buffer, at least four bytes + * @len: length of channel status buffer + * + * Fill the unspecified bits in an IEC958 status bits array using the + * parameters of the PCM hardware parameters @params. + * + * Drivers may wish to tweak the contents of the buffer after its been + * filled.. + * + * Returns: length of buffer, or negative error code if something failed. + */ +int snd_pcm_fill_iec958_consumer_hw_params(struct snd_pcm_hw_params *params, + u8 *cs, size_t len) +{ + return fill_iec958_consumer(params_rate(params), params_width(params), cs, len); } +EXPORT_SYMBOL_GPL(snd_pcm_fill_iec958_consumer_hw_params); /** * snd_pcm_create_iec958_consumer - create consumer format IEC958 channel status @@ -95,9 +176,13 @@ static int create_iec958_consumer(uint rate, uint sample_width, int snd_pcm_create_iec958_consumer(struct snd_pcm_runtime *runtime, u8 *cs, size_t len) { - return create_iec958_consumer(runtime->rate, - snd_pcm_format_width(runtime->format), - cs, len); + int ret; + + ret = snd_pcm_create_iec958_consumer_default(cs, len); + if (ret < 0) + return ret; + + return snd_pcm_fill_iec958_consumer(runtime, cs, len); } EXPORT_SYMBOL(snd_pcm_create_iec958_consumer); @@ -117,7 +202,12 @@ EXPORT_SYMBOL(snd_pcm_create_iec958_consumer); int snd_pcm_create_iec958_consumer_hw_params(struct snd_pcm_hw_params *params, u8 *cs, size_t len) { - return create_iec958_consumer(params_rate(params), params_width(params), - cs, len); + int ret; + + ret = snd_pcm_create_iec958_consumer_default(cs, len); + if (ret < 0) + return ret; + + return fill_iec958_consumer(params_rate(params), params_width(params), cs, len); } EXPORT_SYMBOL(snd_pcm_create_iec958_consumer_hw_params); |