From 58cd33c0f375578cfda25a52ed280caa888b6254 Mon Sep 17 00:00:00 2001 From: Mark Brown Date: Tue, 29 Jul 2008 11:42:25 +0100 Subject: [PATCH] ALSA: ASoC: Allow codecs to override register display Some codecs have unusual features in their register maps such as very large registers representing arrays of coefficients. Support these codecs in the register cache sysfs file by allowing them to provide a function register_display() overriding the default output for register contents. Also ensure that we don't overflow PAGE_SIZE while writing out the register dump. Signed-off-by: Mark Brown Signed-off-by: Takashi Iwai Signed-off-by: Jaroslav Kysela --- include/sound/soc.h | 2 ++ sound/soc/soc-core.c | 26 +++++++++++++++++++++++--- 2 files changed, 25 insertions(+), 3 deletions(-) diff --git a/include/sound/soc.h b/include/sound/soc.h index 1890d87c5204..2ce530efcf11 100644 --- a/include/sound/soc.h +++ b/include/sound/soc.h @@ -410,6 +410,8 @@ struct snd_soc_codec { void *control_data; /* codec control (i2c/3wire) data */ unsigned int (*read)(struct snd_soc_codec *, unsigned int); int (*write)(struct snd_soc_codec *, unsigned int, unsigned int); + int (*display_register)(struct snd_soc_codec *, char *, + size_t, unsigned int); hw_write_t hw_write; hw_read_t hw_read; void *reg_cache; diff --git a/sound/soc/soc-core.c b/sound/soc/soc-core.c index 83f1190293a8..5d3bf731a4b2 100644 --- a/sound/soc/soc-core.c +++ b/sound/soc/soc-core.c @@ -970,9 +970,29 @@ static ssize_t codec_reg_show(struct device *dev, step = codec->reg_cache_step; count += sprintf(buf, "%s registers\n", codec->name); - for (i = 0; i < codec->reg_cache_size; i += step) - count += sprintf(buf + count, "%2x: %4x\n", i, - codec->read(codec, i)); + for (i = 0; i < codec->reg_cache_size; i += step) { + count += sprintf(buf + count, "%2x: ", i); + if (count >= PAGE_SIZE - 1) + break; + + if (codec->display_register) + count += codec->display_register(codec, buf + count, + PAGE_SIZE - count, i); + else + count += snprintf(buf + count, PAGE_SIZE - count, + "%4x", codec->read(codec, i)); + + if (count >= PAGE_SIZE - 1) + break; + + count += snprintf(buf + count, PAGE_SIZE - count, "\n"); + if (count >= PAGE_SIZE - 1) + break; + } + + /* Truncate count; min() would cause a warning */ + if (count >= PAGE_SIZE) + count = PAGE_SIZE - 1; return count; } -- 2.20.1