diff options
Diffstat (limited to 'sound/soc/soc-io.c')
| -rw-r--r-- | sound/soc/soc-io.c | 170 |
1 files changed, 170 insertions, 0 deletions
diff --git a/sound/soc/soc-io.c b/sound/soc/soc-io.c new file mode 100644 index 00000000..4d8dc6a2 --- /dev/null +++ b/sound/soc/soc-io.c @@ -0,0 +1,170 @@ +/* + * soc-io.c -- ASoC register I/O helpers + * + * Copyright 2009-2011 Wolfson Microelectronics PLC. + * + * Author: Mark Brown <broonie@opensource.wolfsonmicro.com> + * + * This program is free software; you can redistribute it and/or modify it + * under the terms of the GNU General Public License as published by the + * Free Software Foundation; either version 2 of the License, or (at your + * option) any later version. + */ + +#include <linux/i2c.h> +#include <linux/spi/spi.h> +#include <linux/regmap.h> +#include <linux/export.h> +#include <sound/soc.h> + +#include <trace/events/asoc.h> + +#ifdef CONFIG_REGMAP +static int hw_write(struct snd_soc_codec *codec, unsigned int reg, + unsigned int value) +{ + int ret; + + if (!snd_soc_codec_volatile_register(codec, reg) && + reg < codec->driver->reg_cache_size && + !codec->cache_bypass) { + ret = snd_soc_cache_write(codec, reg, value); + if (ret < 0) + return -1; + } + + if (codec->cache_only) { + codec->cache_sync = 1; + return 0; + } + + return regmap_write(codec->control_data, reg, value); +} + +static unsigned int hw_read(struct snd_soc_codec *codec, unsigned int reg) +{ + int ret; + unsigned int val; + + if (reg >= codec->driver->reg_cache_size || + snd_soc_codec_volatile_register(codec, reg) || + codec->cache_bypass) { + if (codec->cache_only) + return -1; + + ret = regmap_read(codec->control_data, reg, &val); + if (ret == 0) + return val; + else + return -1; + } + + ret = snd_soc_cache_read(codec, reg, &val); + if (ret < 0) + return -1; + return val; +} + +/* Primitive bulk write support for soc-cache. The data pointed to by + * `data' needs to already be in the form the hardware expects. Any + * data written through this function will not go through the cache as + * it only handles writing to volatile or out of bounds registers. + * + * This is currently only supported for devices using the regmap API + * wrappers. + */ +static int snd_soc_hw_bulk_write_raw(struct snd_soc_codec *codec, + unsigned int reg, + const void *data, size_t len) +{ + /* To ensure that we don't get out of sync with the cache, check + * whether the base register is volatile or if we've directly asked + * to bypass the cache. Out of bounds registers are considered + * volatile. + */ + if (!codec->cache_bypass + && !snd_soc_codec_volatile_register(codec, reg) + && reg < codec->driver->reg_cache_size) + return -EINVAL; + + return regmap_raw_write(codec->control_data, reg, data, len); +} + +/** + * snd_soc_codec_set_cache_io: Set up standard I/O functions. + * + * @codec: CODEC to configure. + * @addr_bits: Number of bits of register address data. + * @data_bits: Number of bits of data per register. + * @control: Control bus used. + * + * Register formats are frequently shared between many I2C and SPI + * devices. In order to promote code reuse the ASoC core provides + * some standard implementations of CODEC read and write operations + * which can be set up using this function. + * + * The caller is responsible for allocating and initialising the + * actual cache. + * + * Note that at present this code cannot be used by CODECs with + * volatile registers. + */ +int snd_soc_codec_set_cache_io(struct snd_soc_codec *codec, + int addr_bits, int data_bits, + enum snd_soc_control_type control) +{ + struct regmap_config config; + int ret; + + memset(&config, 0, sizeof(config)); + codec->write = hw_write; + codec->read = hw_read; + codec->bulk_write_raw = snd_soc_hw_bulk_write_raw; + + config.reg_bits = addr_bits; + config.val_bits = data_bits; + + switch (control) { +#if defined(CONFIG_REGMAP_I2C) || defined(CONFIG_REGMAP_I2C_MODULE) + case SND_SOC_I2C: + codec->control_data = regmap_init_i2c(to_i2c_client(codec->dev), + &config); + break; +#endif + +#if defined(CONFIG_REGMAP_SPI) || defined(CONFIG_REGMAP_SPI_MODULE) + case SND_SOC_SPI: + codec->control_data = regmap_init_spi(to_spi_device(codec->dev), + &config); + break; +#endif + + case SND_SOC_REGMAP: + /* Device has made its own regmap arrangements */ + codec->using_regmap = true; + + ret = regmap_get_val_bytes(codec->control_data); + /* Errors are legitimate for non-integer byte multiples */ + if (ret > 0) + codec->val_bytes = ret; + break; + + default: + return -EINVAL; + } + + if (IS_ERR(codec->control_data)) + return PTR_ERR(codec->control_data); + + return 0; +} +EXPORT_SYMBOL_GPL(snd_soc_codec_set_cache_io); +#else +int snd_soc_codec_set_cache_io(struct snd_soc_codec *codec, + int addr_bits, int data_bits, + enum snd_soc_control_type control) +{ + return -ENOTSUPP; +} +EXPORT_SYMBOL_GPL(snd_soc_codec_set_cache_io); +#endif |