regmap: Add provisions to have user-defined read operation

This commit is a preparatory commit to provide "no-bus" configuration
option for regmap API. It adds necessary plumbing needed to have the
ability to provide user define register read function.

Signed-off-by: Andrey Smirnov <andrew.smirnov@gmail.com>
Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>

diff --git a/drivers/base/regmap/internal.h b/drivers/base/regmap/internal.h
index 401d191..471eb90 100644 (file)
--- a/drivers/base/regmap/internal.h
+++ b/drivers/base/regmap/internal.h
@@ -74,6 +74,8 @@ struct regmap {
        const struct regmap_access_table *volatile_table;
        const struct regmap_access_table *precious_table;
 
+       int (*reg_read)(void *context, unsigned int reg, unsigned int *val);
+
        u8 read_flag_mask;
        u8 write_flag_mask;
 

diff --git a/drivers/base/regmap/regmap.c b/drivers/base/regmap/regmap.c
index 42d5cb0..ceaefcf 100644 (file)
--- a/drivers/base/regmap/regmap.c
+++ b/drivers/base/regmap/regmap.c
@@ -34,6 +34,9 @@ static int _regmap_update_bits(struct regmap *map, unsigned int reg,
                               unsigned int mask, unsigned int val,
                               bool *change);
 
+static int _regmap_bus_read(void *context, unsigned int reg,
+                           unsigned int *val);
+
 bool regmap_reg_in_ranges(unsigned int reg,
                          const struct regmap_range *ranges,
                          unsigned int nranges)
@@ -430,6 +433,8 @@ struct regmap *regmap_init(struct device *dev,
                map->read_flag_mask = bus->read_flag_mask;
        }
 
+       map->reg_read = _regmap_bus_read;
+
        reg_endian = config->reg_format_endian;
        if (reg_endian == REGMAP_ENDIAN_DEFAULT)
                reg_endian = bus->reg_format_endian_default;
@@ -1202,10 +1207,27 @@ static int _regmap_raw_read(struct regmap *map, unsigned int reg, void *val,
        return ret;
 }
 
+static int _regmap_bus_read(void *context, unsigned int reg,
+                           unsigned int *val)
+{
+       int ret;
+       struct regmap *map = context;
+
+       if (!map->format.parse_val)
+               return -EINVAL;
+
+       ret = _regmap_raw_read(map, reg, map->work_buf, map->format.val_bytes);
+       if (ret == 0)
+               *val = map->format.parse_val(map->work_buf);
+
+       return ret;
+}
+
 static int _regmap_read(struct regmap *map, unsigned int reg,
                        unsigned int *val)
 {
        int ret;
+       BUG_ON(!map->reg_read);
 
        if (!map->cache_bypass) {
                ret = regcache_read(map, reg, val);
@@ -1213,26 +1235,21 @@ static int _regmap_read(struct regmap *map, unsigned int reg,
                        return 0;
        }
 
-       if (!map->format.parse_val)
-               return -EINVAL;
-
        if (map->cache_only)
                return -EBUSY;
 
-       ret = _regmap_raw_read(map, reg, map->work_buf, map->format.val_bytes);
+       ret = map->reg_read(map, reg, val);
        if (ret == 0) {
-               *val = map->format.parse_val(map->work_buf);
-
 #ifdef LOG_DEVICE
                if (strcmp(dev_name(map->dev), LOG_DEVICE) == 0)
                        dev_info(map->dev, "%x => %x\n", reg, *val);
 #endif
 
                trace_regmap_reg_read(map->dev, reg, *val);
-       }
 
-       if (ret == 0 && !map->cache_bypass)
-               regcache_write(map, reg, *val);
+               if (!map->cache_bypass)
+                       regcache_write(map, reg, *val);
+       }
 
        return ret;
 }