From 141eba2e006dd8145bed2e49fae3de5af65ab9b0 Mon Sep 17 00:00:00 2001 From: Stephen Warren Date: Thu, 24 May 2012 10:47:26 -0600 Subject: [PATCH] regmap: allow busses to request formatting with specific endianness Add a field to struct regmap_bus that allows bus drivers to request that register addresses and values be formatted with a specific endianness. The default endianness is unchanged from current operation: Big. Implement native endian formatting/parsing for 16- and 32-bit values. This will be enough to support regmap-mmio.c. Signed-off-by: Stephen Warren Signed-off-by: Mark Brown --- drivers/base/regmap/regmap.c | 101 +++++++++++++++++++++++++++++++---- include/linux/regmap.h | 25 +++++++++ 2 files changed, 115 insertions(+), 11 deletions(-) diff --git a/drivers/base/regmap/regmap.c b/drivers/base/regmap/regmap.c index 0bcda488f11..1cf721421be 100644 --- a/drivers/base/regmap/regmap.c +++ b/drivers/base/regmap/regmap.c @@ -119,13 +119,19 @@ static void regmap_format_8(void *buf, unsigned int val, unsigned int shift) b[0] = val << shift; } -static void regmap_format_16(void *buf, unsigned int val, unsigned int shift) +static void regmap_format_16_be(void *buf, unsigned int val, unsigned int shift) { __be16 *b = buf; b[0] = cpu_to_be16(val << shift); } +static void regmap_format_16_native(void *buf, unsigned int val, + unsigned int shift) +{ + *(u16 *)buf = val << shift; +} + static void regmap_format_24(void *buf, unsigned int val, unsigned int shift) { u8 *b = buf; @@ -137,13 +143,19 @@ static void regmap_format_24(void *buf, unsigned int val, unsigned int shift) b[2] = val; } -static void regmap_format_32(void *buf, unsigned int val, unsigned int shift) +static void regmap_format_32_be(void *buf, unsigned int val, unsigned int shift) { __be32 *b = buf; b[0] = cpu_to_be32(val << shift); } +static void regmap_format_32_native(void *buf, unsigned int val, + unsigned int shift) +{ + *(u32 *)buf = val << shift; +} + static unsigned int regmap_parse_8(void *buf) { u8 *b = buf; @@ -151,7 +163,7 @@ static unsigned int regmap_parse_8(void *buf) return b[0]; } -static unsigned int regmap_parse_16(void *buf) +static unsigned int regmap_parse_16_be(void *buf) { __be16 *b = buf; @@ -160,6 +172,11 @@ static unsigned int regmap_parse_16(void *buf) return b[0]; } +static unsigned int regmap_parse_16_native(void *buf) +{ + return *(u16 *)buf; +} + static unsigned int regmap_parse_24(void *buf) { u8 *b = buf; @@ -170,7 +187,7 @@ static unsigned int regmap_parse_24(void *buf) return ret; } -static unsigned int regmap_parse_32(void *buf) +static unsigned int regmap_parse_32_be(void *buf) { __be32 *b = buf; @@ -179,6 +196,11 @@ static unsigned int regmap_parse_32(void *buf) return b[0]; } +static unsigned int regmap_parse_32_native(void *buf) +{ + return *(u32 *)buf; +} + static void regmap_lock_mutex(struct regmap *map) { mutex_lock(&map->mutex); @@ -227,6 +249,7 @@ struct regmap *regmap_init(struct device *dev, { struct regmap *map, **m; int ret = -EINVAL; + enum regmap_endian reg_endian, val_endian; if (!bus || !config) goto err; @@ -275,6 +298,18 @@ struct regmap *regmap_init(struct device *dev, map->read_flag_mask = bus->read_flag_mask; } + reg_endian = config->reg_format_endian; + if (reg_endian == REGMAP_ENDIAN_DEFAULT) + reg_endian = bus->reg_format_endian_default; + if (reg_endian == REGMAP_ENDIAN_DEFAULT) + reg_endian = REGMAP_ENDIAN_BIG; + + val_endian = config->val_format_endian; + if (val_endian == REGMAP_ENDIAN_DEFAULT) + val_endian = bus->val_format_endian_default; + if (val_endian == REGMAP_ENDIAN_DEFAULT) + val_endian = REGMAP_ENDIAN_BIG; + switch (config->reg_bits + map->reg_shift) { case 2: switch (config->val_bits) { @@ -321,11 +356,29 @@ struct regmap *regmap_init(struct device *dev, break; case 16: - map->format.format_reg = regmap_format_16; + switch (reg_endian) { + case REGMAP_ENDIAN_BIG: + map->format.format_reg = regmap_format_16_be; + break; + case REGMAP_ENDIAN_NATIVE: + map->format.format_reg = regmap_format_16_native; + break; + default: + goto err_map; + } break; case 32: - map->format.format_reg = regmap_format_32; + switch (reg_endian) { + case REGMAP_ENDIAN_BIG: + map->format.format_reg = regmap_format_32_be; + break; + case REGMAP_ENDIAN_NATIVE: + map->format.format_reg = regmap_format_32_native; + break; + default: + goto err_map; + } break; default: @@ -338,21 +391,47 @@ struct regmap *regmap_init(struct device *dev, map->format.parse_val = regmap_parse_8; break; case 16: - map->format.format_val = regmap_format_16; - map->format.parse_val = regmap_parse_16; + switch (val_endian) { + case REGMAP_ENDIAN_BIG: + map->format.format_val = regmap_format_16_be; + map->format.parse_val = regmap_parse_16_be; + break; + case REGMAP_ENDIAN_NATIVE: + map->format.format_val = regmap_format_16_native; + map->format.parse_val = regmap_parse_16_native; + break; + default: + goto err_map; + } break; case 24: + if (val_endian != REGMAP_ENDIAN_BIG) + goto err_map; map->format.format_val = regmap_format_24; map->format.parse_val = regmap_parse_24; break; case 32: - map->format.format_val = regmap_format_32; - map->format.parse_val = regmap_parse_32; + switch (val_endian) { + case REGMAP_ENDIAN_BIG: + map->format.format_val = regmap_format_32_be; + map->format.parse_val = regmap_parse_32_be; + break; + case REGMAP_ENDIAN_NATIVE: + map->format.format_val = regmap_format_32_native; + map->format.parse_val = regmap_parse_32_native; + break; + default: + goto err_map; + } break; } - if (map->format.format_write) + if (map->format.format_write) { + if ((reg_endian != REGMAP_ENDIAN_BIG) || + (val_endian != REGMAP_ENDIAN_BIG)) + goto err_map; map->use_single_rw = true; + } if (!map->format.format_write && !(map->format.format_reg && map->format.format_val)) diff --git a/include/linux/regmap.h b/include/linux/regmap.h index 56af22ec9ab..26136b57700 100644 --- a/include/linux/regmap.h +++ b/include/linux/regmap.h @@ -43,6 +43,14 @@ struct reg_default { #ifdef CONFIG_REGMAP +enum regmap_endian { + /* Unspecified -> 0 -> Backwards compatible default */ + REGMAP_ENDIAN_DEFAULT = 0, + REGMAP_ENDIAN_BIG, + REGMAP_ENDIAN_LITTLE, + REGMAP_ENDIAN_NATIVE, +}; + /** * Configuration for the register map of a device. * @@ -84,6 +92,12 @@ struct reg_default { * @reg_defaults_raw: Power on reset values for registers (for use with * register cache support). * @num_reg_defaults_raw: Number of elements in reg_defaults_raw. + * @reg_format_endian: Endianness for formatted register addresses. If this is + * DEFAULT, the @reg_format_endian_default value from the + * regmap bus is used. + * @val_format_endian: Endianness for formatted register values. If this is + * DEFAULT, the @reg_format_endian_default value from the + * regmap bus is used. */ struct regmap_config { const char *name; @@ -109,6 +123,9 @@ struct regmap_config { u8 write_flag_mask; bool use_single_rw; + + enum regmap_endian reg_format_endian; + enum regmap_endian val_format_endian; }; typedef int (*regmap_hw_write)(void *context, const void *data, @@ -133,6 +150,12 @@ typedef void (*regmap_hw_free_context)(void *context); * data. * @read_flag_mask: Mask to be set in the top byte of the register when doing * a read. + * @reg_format_endian_default: Default endianness for formatted register + * addresses. Used when the regmap_config specifies DEFAULT. If this is + * DEFAULT, BIG is assumed. + * @val_format_endian_default: Default endianness for formatted register + * values. Used when the regmap_config specifies DEFAULT. If this is + * DEFAULT, BIG is assumed. */ struct regmap_bus { bool fast_io; @@ -141,6 +164,8 @@ struct regmap_bus { regmap_hw_read read; regmap_hw_free_context free_context; u8 read_flag_mask; + enum regmap_endian reg_format_endian_default; + enum regmap_endian val_format_endian_default; }; struct regmap *regmap_init(struct device *dev, -- 2.41.0