diff mbox series

[v6,5/9] regmap: Introduces regmap lock helpers

Message ID 20211224041352.29405-6-quan@os.amperecomputing.com
State New
Headers show
Series Add Ampere's Altra SMPro MFD and its child drivers | expand

Commit Message

Quan Nguyen Dec. 24, 2021, 4:13 a.m. UTC
This commit introduces regmap_acquire/release_lock() functions and makes
them available for drivers that need atomic access of regmap registers

Signed-off-by: Quan Nguyen <quan@os.amperecomputing.com>
---
Change in v6:
  + First introduced in v6 [Quan]

 drivers/base/regmap/regmap.c | 12 ++++++++++++
 include/linux/regmap.h       |  2 ++
 2 files changed, 14 insertions(+)

Comments

Mark Brown Dec. 24, 2021, 1:19 p.m. UTC | #1
On Fri, Dec 24, 2021 at 11:13:48AM +0700, Quan Nguyen wrote:
> This commit introduces regmap_acquire/release_lock() functions and makes
> them available for drivers that need atomic access of regmap registers

You've not explained what something would need this for and how
it's expected to work - we don't provide unlocked access to the
regmap to client drivers so I don't see how one could safely use
this.  It's unclear to me what this would mean or why it's not
better implemented in the client driver.
Quan Nguyen March 7, 2022, 8:31 a.m. UTC | #2
On 24/12/2021 20:19, Mark Brown wrote:
> On Fri, Dec 24, 2021 at 11:13:48AM +0700, Quan Nguyen wrote:
>> This commit introduces regmap_acquire/release_lock() functions and makes
>> them available for drivers that need atomic access of regmap registers
> 
> You've not explained what something would need this for and how
> it's expected to work - we don't provide unlocked access to the
> regmap to client drivers so I don't see how one could safely use
> this.  It's unclear to me what this would mean or why it's not
> better implemented in the client driver.

Thanks a lot for the review, Mark.
As per my comment in the other email, this code will be removed in my 
next version.

Thanks,
- Quan
diff mbox series

Patch

diff --git a/drivers/base/regmap/regmap.c b/drivers/base/regmap/regmap.c
index 2d74f9f82aa9..36921309725b 100644
--- a/drivers/base/regmap/regmap.c
+++ b/drivers/base/regmap/regmap.c
@@ -87,6 +87,18 @@  bool regmap_check_range_table(struct regmap *map, unsigned int reg,
 }
 EXPORT_SYMBOL_GPL(regmap_check_range_table);
 
+void regmap_acquire_lock(struct regmap *map)
+{
+	map->lock(map->lock_arg);
+}
+EXPORT_SYMBOL_GPL(regmap_acquire_lock);
+
+void regmap_release_lock(struct regmap *map)
+{
+	map->unlock(map->lock_arg);
+}
+EXPORT_SYMBOL_GPL(regmap_release_lock);
+
 bool regmap_writeable(struct regmap *map, unsigned int reg)
 {
 	if (map->max_register && reg > map->max_register)
diff --git a/include/linux/regmap.h b/include/linux/regmap.h
index 22652e5fbc38..0ed12e6ad4fb 100644
--- a/include/linux/regmap.h
+++ b/include/linux/regmap.h
@@ -1194,6 +1194,8 @@  int regmap_async_complete(struct regmap *map);
 bool regmap_can_raw_write(struct regmap *map);
 size_t regmap_get_raw_read_max(struct regmap *map);
 size_t regmap_get_raw_write_max(struct regmap *map);
+void regmap_acquire_lock(struct regmap *map);
+void regmap_release_lock(struct regmap *map);
 
 int regcache_sync(struct regmap *map);
 int regcache_sync_region(struct regmap *map, unsigned int min,