This is a note to let you know that I've just added the patch titled
regmap: Add bulk read/write callbacks into regmap_config
to the 5.4-stable tree which can be found at:
http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary
The filename of the patch is:
regmap-add-bulk-read-write-callbacks-into-regmap_con.patch
and it can be found in the queue-5.4 subdirectory.
If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@xxxxxxxxxxxxxxx> know about it.
commit 252006fc58a9519446186d9f0ef8b0b98e604b44
Author: Marek Vasut <marex@xxxxxxx>
Date: Sat Apr 30 04:51:44 2022 +0200
regmap: Add bulk read/write callbacks into regmap_config
[ Upstream commit d77e745613680c54708470402e2b623dcd769681 ]
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@xxxxxxx>
Cc: Jagan Teki <jagan@xxxxxxxxxxxxxxxxxxxx>
Cc: Mark Brown <broonie@xxxxxxxxxx>
Cc: Maxime Ripard <maxime@xxxxxxxxxx>
Cc: Robert Foss <robert.foss@xxxxxxxxxx>
Cc: Sam Ravnborg <sam@xxxxxxxxxxxx>
Cc: Thomas Zimmermann <tzimmermann@xxxxxxx>
To: dri-devel@xxxxxxxxxxxxxxxxxxxxx
Link: https://lore.kernel.org/r/20220430025145.640305-1-marex@xxxxxxx
Signed-off-by: Mark Brown <broonie@xxxxxxxxxx>
Stable-dep-of: 3f42b142ea11 ("serial: max310x: fix IO data corruption in batched operations")
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
diff --git a/drivers/base/regmap/internal.h b/drivers/base/regmap/internal.h
index d7c01b70e43db..af6ac068ca5d3 100644
--- a/drivers/base/regmap/internal.h
+++ b/drivers/base/regmap/internal.h
@@ -104,6 +104,10 @@ 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 961b206f6ab2d..6f580883c1973 100644
--- a/drivers/base/regmap/regmap.c
+++ b/drivers/base/regmap/regmap.c
@@ -771,12 +771,15 @@ 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;
@@ -810,7 +813,16 @@ 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;
@@ -826,10 +838,13 @@ 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:
@@ -1480,8 +1495,6 @@ 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
*/
@@ -1563,7 +1576,7 @@ 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);
@@ -1631,10 +1644,10 @@ 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 +
@@ -1653,7 +1666,7 @@ 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) {
@@ -1710,7 +1723,7 @@ 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) {
@@ -1723,8 +1736,7 @@ 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);
@@ -1744,7 +1756,7 @@ 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);
@@ -1758,7 +1770,7 @@ 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,
@@ -2167,7 +2179,7 @@ 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);
@@ -2465,9 +2477,7 @@ 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);
@@ -2483,9 +2493,9 @@ 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);
@@ -2596,8 +2606,6 @@ 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))
@@ -2612,7 +2620,7 @@ 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;
}
@@ -2672,7 +2680,7 @@ 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.
*
@@ -2690,10 +2698,6 @@ 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))
@@ -2807,7 +2811,7 @@ 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 29661bbd137d7..edc095434787b 100644
--- a/include/linux/regmap.h
+++ b/include/linux/regmap.h
@@ -300,6 +300,12 @@ 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).
@@ -378,6 +384,12 @@ 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;
