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Diffstat (limited to 'sound/core/pcm_iec958.c')
-rw-r--r--sound/core/pcm_iec958.c174
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);