On 2021/3/16 16:56, Song Bao Hua (Barry Song) wrote:
-----Original Message----- From: Yicong Yang [mailto:yangyicong@hisilicon.com] Sent: Wednesday, March 10, 2021 2:22 AM To: wsa@kernel.org; linux-i2c@vger.kernel.org Cc: linuxarm@openeuler.org; Zengtao (B) prime.zeng@hisilicon.com; yangyicong yangyicong@huawei.com Subject: [Linuxarm] [PATCH v2 1/3] i2c: core: add managed function for adding i2c adapters
Some I2C controller drivers will only unregister the I2C adapter in their .remove() callback, which can be done by simply using a managed variant to add the I2C adapter.
So add the managed functions for adding the I2C adapter.
Sounds like a very useful wrapper. We are able to remove some "remove" callbacks afterwards. We have some similar wrappers like devm_hwrng_register which is always helpful.
devm_* are widely used for helping managing the resources and simplify the driver in other subsystems, so i think i2c core will also benefit from this. :) thanks for looking into this patch.
Regards, Yicong
Signed-off-by: Yicong Yang yangyicong@hisilicon.com
drivers/i2c/i2c-core-base.c | 39 +++++++++++++++++++++++++++++++++++++++ include/linux/i2c.h | 1 + 2 files changed, 40 insertions(+)
diff --git a/drivers/i2c/i2c-core-base.c b/drivers/i2c/i2c-core-base.c index 63ebf72..61486dc 100644 --- a/drivers/i2c/i2c-core-base.c +++ b/drivers/i2c/i2c-core-base.c @@ -1550,6 +1550,38 @@ int i2c_add_adapter(struct i2c_adapter *adapter) } EXPORT_SYMBOL(i2c_add_adapter);
+static void devm_i2c_del_adapter(struct device *dev, void *ptr);
+/**
- devm_i2c_add_adapter - device-managed variant of i2c_add_adapter()
- @dev: managing device for adding this I2C adapter
- @adapter: the adapter to add
- Context: can sleep
- Add adapter with dynamic bus number, same with i2c_add_adapter()
- but the adapter will be auto deleted on driver detach.
- */
+int devm_i2c_add_adapter(struct device *dev, struct i2c_adapter *adapter) +{
- struct i2c_adapter **ptr;
- int ret;
- ptr = devres_alloc(devm_i2c_del_adapter, sizeof(*ptr), GFP_KERNEL);
- if (!ptr)
return -ENOMEM;- ret = i2c_add_adapter(adapter);
- if (!ret) {
*ptr = adapter;devres_add(dev, ptr);- } else {
devres_free(ptr);- }
- return ret;
+} +EXPORT_SYMBOL(devm_i2c_add_adapter);
/**
- i2c_add_numbered_adapter - declare i2c adapter, use static bus number
- @adap: the adapter to register (with adap->nr initialized)
@@ -1703,6 +1735,13 @@ void i2c_del_adapter(struct i2c_adapter *adap) } EXPORT_SYMBOL(i2c_del_adapter);
+static void devm_i2c_del_adapter(struct device *dev, void *ptr) +{
- struct i2c_adapter *adapter = *((struct i2c_adapter **)ptr);
- i2c_del_adapter(adapter);
+}
static void i2c_parse_timing(struct device *dev, char *prop_name, u32 *cur_val_p, u32 def_val, bool use_def) { diff --git a/include/linux/i2c.h b/include/linux/i2c.h index 5662265..10bd0b0 100644 --- a/include/linux/i2c.h +++ b/include/linux/i2c.h @@ -844,6 +844,7 @@ static inline void i2c_mark_adapter_resumed(struct i2c_adapter *adap) */ #if IS_ENABLED(CONFIG_I2C) int i2c_add_adapter(struct i2c_adapter *adap); +int devm_i2c_add_adapter(struct device *dev, struct i2c_adapter *adapter); void i2c_del_adapter(struct i2c_adapter *adap); int i2c_add_numbered_adapter(struct i2c_adapter *adap);
-- 2.8.1
Thanks Barry