[PATCH 1/2] [RFC] regmap: Add bulk read/write callbacks into regmap_config
Marek Vasut
marex at denx.de
Sat Apr 30 02:51:44 UTC 2022
Currently the regmap_config structure only allows the user to implement
single element register read/write using .reg_read/.reg_write callbacks.
The regmap_bus already implements bulk counterparts of both, and is being
misused as a workaround for the missing bulk read/write callbacks in
regmap_config by a couple of drivers. To stop this misuse, add the bulk
read/write callbacks to regmap_config and call them from the regmap core
code.
Signed-off-by: Marek Vasut <marex at denx.de>
Cc: Jagan Teki <jagan at amarulasolutions.com>
Cc: Mark Brown <broonie at kernel.org>
Cc: Maxime Ripard <maxime at cerno.tech>
Cc: Robert Foss <robert.foss at linaro.org>
Cc: Sam Ravnborg <sam at ravnborg.org>
Cc: Thomas Zimmermann <tzimmermann at suse.de>
To: dri-devel at lists.freedesktop.org
---
drivers/base/regmap/internal.h | 4 ++
drivers/base/regmap/regmap.c | 76 ++++++++++++++++++----------------
include/linux/regmap.h | 12 ++++++
3 files changed, 56 insertions(+), 36 deletions(-)
diff --git a/drivers/base/regmap/internal.h b/drivers/base/regmap/internal.h
index b4df36c7b17d..da8996e7a1f1 100644
--- a/drivers/base/regmap/internal.h
+++ b/drivers/base/regmap/internal.h
@@ -110,6 +110,10 @@ struct regmap {
int (*reg_write)(void *context, unsigned int reg, unsigned int val);
int (*reg_update_bits)(void *context, unsigned int reg,
unsigned int mask, unsigned int val);
+ /* Bulk read/write */
+ int (*read)(void *context, const void *reg_buf, size_t reg_size,
+ void *val_buf, size_t val_size);
+ int (*write)(void *context, const void *data, size_t count);
bool defer_caching;
diff --git a/drivers/base/regmap/regmap.c b/drivers/base/regmap/regmap.c
index 5e12f7cb5147..879a87a6461b 100644
--- a/drivers/base/regmap/regmap.c
+++ b/drivers/base/regmap/regmap.c
@@ -838,12 +838,15 @@ struct regmap *__regmap_init(struct device *dev,
map->reg_stride_order = ilog2(map->reg_stride);
else
map->reg_stride_order = -1;
- map->use_single_read = config->use_single_read || !bus || !bus->read;
- map->use_single_write = config->use_single_write || !bus || !bus->write;
- map->can_multi_write = config->can_multi_write && bus && bus->write;
+ map->use_single_read = config->use_single_read || !(config->read || (bus && bus->read));
+ map->use_single_write = config->use_single_write || !(config->write || (bus && bus->write));
+ map->can_multi_write = config->can_multi_write && (config->write || (bus && bus->write));
if (bus) {
map->max_raw_read = bus->max_raw_read;
map->max_raw_write = bus->max_raw_write;
+ } else if (config->max_raw_read && config->max_raw_write) {
+ map->max_raw_read = config->max_raw_read;
+ map->max_raw_write = config->max_raw_write;
}
map->dev = dev;
map->bus = bus;
@@ -877,7 +880,16 @@ struct regmap *__regmap_init(struct device *dev,
map->read_flag_mask = bus->read_flag_mask;
}
- if (!bus) {
+ if (config && config->read && config->write) {
+ map->reg_read = _regmap_bus_read;
+
+ /* Bulk read/write */
+ map->read = config->read;
+ map->write = config->write;
+
+ reg_endian = REGMAP_ENDIAN_NATIVE;
+ val_endian = REGMAP_ENDIAN_NATIVE;
+ } else if (!bus) {
map->reg_read = config->reg_read;
map->reg_write = config->reg_write;
map->reg_update_bits = config->reg_update_bits;
@@ -894,10 +906,13 @@ struct regmap *__regmap_init(struct device *dev,
} else {
map->reg_read = _regmap_bus_read;
map->reg_update_bits = bus->reg_update_bits;
- }
+ /* Bulk read/write */
+ map->read = bus->read;
+ map->write = bus->write;
- reg_endian = regmap_get_reg_endian(bus, config);
- val_endian = regmap_get_val_endian(dev, bus, config);
+ reg_endian = regmap_get_reg_endian(bus, config);
+ val_endian = regmap_get_val_endian(dev, bus, config);
+ }
switch (config->reg_bits + map->reg_shift) {
case 2:
@@ -1671,8 +1686,6 @@ static int _regmap_raw_write_impl(struct regmap *map, unsigned int reg,
size_t len;
int i;
- WARN_ON(!map->bus);
-
/* Check for unwritable or noinc registers in range
* before we start
*/
@@ -1754,7 +1767,7 @@ static int _regmap_raw_write_impl(struct regmap *map, unsigned int reg,
val = work_val;
}
- if (map->async && map->bus->async_write) {
+ if (map->async && map->bus && map->bus->async_write) {
struct regmap_async *async;
trace_regmap_async_write_start(map, reg, val_len);
@@ -1822,10 +1835,10 @@ static int _regmap_raw_write_impl(struct regmap *map, unsigned int reg,
* write.
*/
if (val == work_val)
- ret = map->bus->write(map->bus_context, map->work_buf,
- map->format.reg_bytes +
- map->format.pad_bytes +
- val_len);
+ ret = map->write(map->bus_context, map->work_buf,
+ map->format.reg_bytes +
+ map->format.pad_bytes +
+ val_len);
else if (map->bus->gather_write)
ret = map->bus->gather_write(map->bus_context, map->work_buf,
map->format.reg_bytes +
@@ -1844,7 +1857,7 @@ static int _regmap_raw_write_impl(struct regmap *map, unsigned int reg,
memcpy(buf, map->work_buf, map->format.reg_bytes);
memcpy(buf + map->format.reg_bytes + map->format.pad_bytes,
val, val_len);
- ret = map->bus->write(map->bus_context, buf, len);
+ ret = map->write(map->bus_context, buf, len);
kfree(buf);
} else if (ret != 0 && !map->cache_bypass && map->format.parse_val) {
@@ -1901,7 +1914,7 @@ static int _regmap_bus_formatted_write(void *context, unsigned int reg,
struct regmap_range_node *range;
struct regmap *map = context;
- WARN_ON(!map->bus || !map->format.format_write);
+ WARN_ON(!map->format.format_write);
range = _regmap_range_lookup(map, reg);
if (range) {
@@ -1916,8 +1929,7 @@ static int _regmap_bus_formatted_write(void *context, unsigned int reg,
trace_regmap_hw_write_start(map, reg, 1);
- ret = map->bus->write(map->bus_context, map->work_buf,
- map->format.buf_size);
+ ret = map->write(map->bus_context, map->work_buf, map->format.buf_size);
trace_regmap_hw_write_done(map, reg, 1);
@@ -1937,7 +1949,7 @@ static int _regmap_bus_raw_write(void *context, unsigned int reg,
{
struct regmap *map = context;
- WARN_ON(!map->bus || !map->format.format_val);
+ WARN_ON(!map->format.format_val);
map->format.format_val(map->work_buf + map->format.reg_bytes
+ map->format.pad_bytes, val, 0);
@@ -1951,7 +1963,7 @@ static int _regmap_bus_raw_write(void *context, unsigned int reg,
static inline void *_regmap_map_get_context(struct regmap *map)
{
- return (map->bus) ? map : map->bus_context;
+ return (map->bus || (!map->bus && map->read)) ? map : map->bus_context;
}
int _regmap_write(struct regmap *map, unsigned int reg,
@@ -2363,7 +2375,7 @@ static int _regmap_raw_multi_reg_write(struct regmap *map,
u8 = buf;
*u8 |= map->write_flag_mask;
- ret = map->bus->write(map->bus_context, buf, len);
+ ret = map->write(map->bus_context, buf, len);
kfree(buf);
@@ -2669,9 +2681,7 @@ static int _regmap_raw_read(struct regmap *map, unsigned int reg, void *val,
struct regmap_range_node *range;
int ret;
- WARN_ON(!map->bus);
-
- if (!map->bus || !map->bus->read)
+ if (!map->read)
return -EINVAL;
range = _regmap_range_lookup(map, reg);
@@ -2689,9 +2699,9 @@ static int _regmap_raw_read(struct regmap *map, unsigned int reg, void *val,
map->read_flag_mask);
trace_regmap_hw_read_start(map, reg, val_len / map->format.val_bytes);
- ret = map->bus->read(map->bus_context, map->work_buf,
- map->format.reg_bytes + map->format.pad_bytes,
- val, val_len);
+ ret = map->read(map->bus_context, map->work_buf,
+ map->format.reg_bytes + map->format.pad_bytes,
+ val, val_len);
trace_regmap_hw_read_done(map, reg, val_len / map->format.val_bytes);
@@ -2802,8 +2812,6 @@ int regmap_raw_read(struct regmap *map, unsigned int reg, void *val,
unsigned int v;
int ret, i;
- if (!map->bus)
- return -EINVAL;
if (val_len % map->format.val_bytes)
return -EINVAL;
if (!IS_ALIGNED(reg, map->reg_stride))
@@ -2818,7 +2826,7 @@ int regmap_raw_read(struct regmap *map, unsigned int reg, void *val,
size_t chunk_count, chunk_bytes;
size_t chunk_regs = val_count;
- if (!map->bus->read) {
+ if (!map->read) {
ret = -ENOTSUPP;
goto out;
}
@@ -2878,7 +2886,7 @@ EXPORT_SYMBOL_GPL(regmap_raw_read);
* @val: Pointer to data buffer
* @val_len: Length of output buffer in bytes.
*
- * The regmap API usually assumes that bulk bus read operations will read a
+ * The regmap API usually assumes that bulk read operations will read a
* range of registers. Some devices have certain registers for which a read
* operation read will read from an internal FIFO.
*
@@ -2896,10 +2904,6 @@ int regmap_noinc_read(struct regmap *map, unsigned int reg,
size_t read_len;
int ret;
- if (!map->bus)
- return -EINVAL;
- if (!map->bus->read)
- return -ENOTSUPP;
if (val_len % map->format.val_bytes)
return -EINVAL;
if (!IS_ALIGNED(reg, map->reg_stride))
@@ -3013,7 +3017,7 @@ int regmap_bulk_read(struct regmap *map, unsigned int reg, void *val,
if (val_count == 0)
return -EINVAL;
- if (map->bus && map->format.parse_inplace && (vol || map->cache_type == REGCACHE_NONE)) {
+ if (map->format.parse_inplace && (vol || map->cache_type == REGCACHE_NONE)) {
ret = regmap_raw_read(map, reg, val, val_bytes * val_count);
if (ret != 0)
return ret;
diff --git a/include/linux/regmap.h b/include/linux/regmap.h
index de81a94d7b30..8952fa3d0d59 100644
--- a/include/linux/regmap.h
+++ b/include/linux/regmap.h
@@ -299,6 +299,12 @@ typedef void (*regmap_unlock)(void *);
* if the function require special handling with lock and reg
* handling and the operation cannot be represented as a simple
* update_bits operation on a bus such as SPI, I2C, etc.
+ * @read: Optional callback that if filled will be used to perform all the
+ * bulk reads from the registers. Data is returned in the buffer used
+ * to transmit data.
+ * @write: Same as above for writing.
+ * @max_raw_read: Max raw read size that can be used on the device.
+ * @max_raw_write: Max raw write size that can be used on the device.
* @fast_io: Register IO is fast. Use a spinlock instead of a mutex
* to perform locking. This field is ignored if custom lock/unlock
* functions are used (see fields lock/unlock of struct regmap_config).
@@ -385,6 +391,12 @@ struct regmap_config {
int (*reg_write)(void *context, unsigned int reg, unsigned int val);
int (*reg_update_bits)(void *context, unsigned int reg,
unsigned int mask, unsigned int val);
+ /* Bulk read/write */
+ int (*read)(void *context, const void *reg_buf, size_t reg_size,
+ void *val_buf, size_t val_size);
+ int (*write)(void *context, const void *data, size_t count);
+ size_t max_raw_read;
+ size_t max_raw_write;
bool fast_io;
--
2.35.1
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