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1// SPDX-License-Identifier: GPL-2.0-only2/*3 * PCM DRM helpers4 */5#include <linux/export.h>6#include <linux/types.h>7#include <sound/asoundef.h>8#include <sound/pcm.h>9#include <sound/pcm_params.h>10#include <sound/pcm_iec958.h>11 12/**13 * snd_pcm_create_iec958_consumer_default - create default consumer format IEC958 channel status14 * @cs: channel status buffer, at least four bytes15 * @len: length of channel status buffer16 *17 * Create the consumer format channel status data in @cs of maximum size18 * @len. When relevant, the configuration-dependant bits will be set as19 * unspecified.20 *21 * Drivers should then call einter snd_pcm_fill_iec958_consumer() or22 * snd_pcm_fill_iec958_consumer_hw_params() to replace these unspecified23 * bits by their actual values.24 *25 * Drivers may wish to tweak the contents of the buffer after creation.26 *27 * Returns: length of buffer, or negative error code if something failed.28 */29int snd_pcm_create_iec958_consumer_default(u8 *cs, size_t len)30{31 if (len < 4)32 return -EINVAL;33 34 memset(cs, 0, len);35 36 cs[0] = IEC958_AES0_CON_NOT_COPYRIGHT | IEC958_AES0_CON_EMPHASIS_NONE;37 cs[1] = IEC958_AES1_CON_GENERAL;38 cs[2] = IEC958_AES2_CON_SOURCE_UNSPEC | IEC958_AES2_CON_CHANNEL_UNSPEC;39 cs[3] = IEC958_AES3_CON_CLOCK_1000PPM | IEC958_AES3_CON_FS_NOTID;40 41 if (len > 4)42 cs[4] = IEC958_AES4_CON_WORDLEN_NOTID;43 44 return len;45}46EXPORT_SYMBOL_GPL(snd_pcm_create_iec958_consumer_default);47 48static int fill_iec958_consumer(uint rate, uint sample_width,49 u8 *cs, size_t len)50{51 if (len < 4)52 return -EINVAL;53 54 if ((cs[3] & IEC958_AES3_CON_FS) == IEC958_AES3_CON_FS_NOTID) {55 unsigned int fs;56 57 switch (rate) {58 case 32000:59 fs = IEC958_AES3_CON_FS_32000;60 break;61 case 44100:62 fs = IEC958_AES3_CON_FS_44100;63 break;64 case 48000:65 fs = IEC958_AES3_CON_FS_48000;66 break;67 case 88200:68 fs = IEC958_AES3_CON_FS_88200;69 break;70 case 96000:71 fs = IEC958_AES3_CON_FS_96000;72 break;73 case 176400:74 fs = IEC958_AES3_CON_FS_176400;75 break;76 case 192000:77 fs = IEC958_AES3_CON_FS_192000;78 break;79 default:80 return -EINVAL;81 }82 83 cs[3] &= ~IEC958_AES3_CON_FS;84 cs[3] |= fs;85 }86 87 if (len > 4 &&88 (cs[4] & IEC958_AES4_CON_WORDLEN) == IEC958_AES4_CON_WORDLEN_NOTID) {89 unsigned int ws;90 91 switch (sample_width) {92 case 16:93 ws = IEC958_AES4_CON_WORDLEN_20_16;94 break;95 case 18:96 ws = IEC958_AES4_CON_WORDLEN_22_18;97 break;98 case 20:99 ws = IEC958_AES4_CON_WORDLEN_20_16 |100 IEC958_AES4_CON_MAX_WORDLEN_24;101 break;102 case 24:103 case 32: /* Assume 24-bit width for 32-bit samples. */104 ws = IEC958_AES4_CON_WORDLEN_24_20 |105 IEC958_AES4_CON_MAX_WORDLEN_24;106 break;107 108 default:109 return -EINVAL;110 }111 112 cs[4] &= ~IEC958_AES4_CON_WORDLEN;113 cs[4] |= ws;114 }115 116 return len;117}118 119/**120 * snd_pcm_fill_iec958_consumer - Fill consumer format IEC958 channel status121 * @runtime: pcm runtime structure with ->rate filled in122 * @cs: channel status buffer, at least four bytes123 * @len: length of channel status buffer124 *125 * Fill the unspecified bits in an IEC958 status bits array using the126 * parameters of the PCM runtime @runtime.127 *128 * Drivers may wish to tweak the contents of the buffer after its been129 * filled.130 *131 * Returns: length of buffer, or negative error code if something failed.132 */133int snd_pcm_fill_iec958_consumer(struct snd_pcm_runtime *runtime,134 u8 *cs, size_t len)135{136 return fill_iec958_consumer(runtime->rate,137 snd_pcm_format_width(runtime->format),138 cs, len);139}140EXPORT_SYMBOL_GPL(snd_pcm_fill_iec958_consumer);141 142/**143 * snd_pcm_fill_iec958_consumer_hw_params - Fill consumer format IEC958 channel status144 * @params: the hw_params instance for extracting rate and sample format145 * @cs: channel status buffer, at least four bytes146 * @len: length of channel status buffer147 *148 * Fill the unspecified bits in an IEC958 status bits array using the149 * parameters of the PCM hardware parameters @params.150 *151 * Drivers may wish to tweak the contents of the buffer after its been152 * filled..153 *154 * Returns: length of buffer, or negative error code if something failed.155 */156int snd_pcm_fill_iec958_consumer_hw_params(struct snd_pcm_hw_params *params,157 u8 *cs, size_t len)158{159 return fill_iec958_consumer(params_rate(params), params_width(params), cs, len);160}161EXPORT_SYMBOL_GPL(snd_pcm_fill_iec958_consumer_hw_params);162 163/**164 * snd_pcm_create_iec958_consumer - create consumer format IEC958 channel status165 * @runtime: pcm runtime structure with ->rate filled in166 * @cs: channel status buffer, at least four bytes167 * @len: length of channel status buffer168 *169 * Create the consumer format channel status data in @cs of maximum size170 * @len corresponding to the parameters of the PCM runtime @runtime.171 *172 * Drivers may wish to tweak the contents of the buffer after creation.173 *174 * Returns: length of buffer, or negative error code if something failed.175 */176int snd_pcm_create_iec958_consumer(struct snd_pcm_runtime *runtime, u8 *cs,177 size_t len)178{179 int ret;180 181 ret = snd_pcm_create_iec958_consumer_default(cs, len);182 if (ret < 0)183 return ret;184 185 return snd_pcm_fill_iec958_consumer(runtime, cs, len);186}187EXPORT_SYMBOL(snd_pcm_create_iec958_consumer);188 189/**190 * snd_pcm_create_iec958_consumer_hw_params - create IEC958 channel status191 * @params: the hw_params instance for extracting rate and sample format192 * @cs: channel status buffer, at least four bytes193 * @len: length of channel status buffer194 *195 * Create the consumer format channel status data in @cs of maximum size196 * @len corresponding to the parameters of the PCM runtime @runtime.197 *198 * Drivers may wish to tweak the contents of the buffer after creation.199 *200 * Returns: length of buffer, or negative error code if something failed.201 */202int snd_pcm_create_iec958_consumer_hw_params(struct snd_pcm_hw_params *params,203 u8 *cs, size_t len)204{205 int ret;206 207 ret = snd_pcm_create_iec958_consumer_default(cs, len);208 if (ret < 0)209 return ret;210 211 return fill_iec958_consumer(params_rate(params), params_width(params), cs, len);212}213EXPORT_SYMBOL(snd_pcm_create_iec958_consumer_hw_params);214