| Message ID | 8c0a982f-30d5-1124-c871-b040b5bce636@gmail.com |
|---|---|
| State | Superseded |
| Headers | show |
On 2017-08-22 07:45, Heiner Kallweit wrote: > i2c_new_dummy is typically called from the probe function of the > driver for the primary i2c client. It requires calls to > i2c_unregister_device in the error path of the probe function and > in the remove function. > This can be simplified by introducing a device-managed version. > > Note the changed error case return value type: > i2c_new_dummy returns NULL whilst devm_new_i2c_dummy returns an ERR_PTR. > > Signed-off-by: Heiner Kallweit <hkallweit1@gmail.com> Looks good to me, assuming you have some user in the wings... Reviewed-by: Peter Rosin <peda@axentia.se> Cheers, peda > --- > v2: > - added entry to Documentation/driver-model/devres.txt > - extended documentation of new function > - changed return value type to an ERR_PTR in case of error > --- > Documentation/driver-model/devres.txt | 3 +++ > drivers/i2c/i2c-core-base.c | 39 +++++++++++++++++++++++++++++++++++ > include/linux/i2c.h | 3 +++ > 3 files changed, 45 insertions(+) > > diff --git a/Documentation/driver-model/devres.txt b/Documentation/driver-model/devres.txt > index 30e04f7a..67d59528 100644 > --- a/Documentation/driver-model/devres.txt > +++ b/Documentation/driver-model/devres.txt > @@ -258,6 +258,9 @@ GPIO > devm_gpio_request_one() > devm_gpio_free() > > +I2C > + devm_i2c_new_dummy > + > IIO > devm_iio_device_alloc() > devm_iio_device_free() > diff --git a/drivers/i2c/i2c-core-base.c b/drivers/i2c/i2c-core-base.c > index 12822a4b..aac9491c 100644 > --- a/drivers/i2c/i2c-core-base.c > +++ b/drivers/i2c/i2c-core-base.c > @@ -868,6 +868,45 @@ struct i2c_client *i2c_new_dummy(struct i2c_adapter *adapter, u16 address) > } > EXPORT_SYMBOL_GPL(i2c_new_dummy); > > +static void devm_i2c_release_dummy(struct device *dev, void *res) > +{ > + i2c_unregister_device(*(struct i2c_client **)res); > +} > + > +/** > + * devm_i2c_new_dummy - return a new i2c device bound to a dummy driver > + * @dev: device the managed resource is bound to > + * @adapter: the adapter managing the device > + * @address: seven bit address to be used > + * Context: can sleep > + * > + * This is the device-managed version of i2c_new_dummy. > + * Note the changed return value type: It returns the new i2c client > + * or an ERR_PTR in case of an error. > + */ > +struct i2c_client *devm_i2c_new_dummy(struct device *dev, > + struct i2c_adapter *adapter, > + u16 address) > +{ > + struct i2c_client *ret, **dr; > + > + dr = devres_alloc(devm_i2c_release_dummy, sizeof(*dr), GFP_KERNEL); > + if (!dr) > + return ERR_PTR(-ENOMEM); > + > + ret = i2c_new_dummy(adapter, address); > + if (!ret) { > + devres_free(dr); > + return ERR_PTR(-EBUSY); > + } > + > + *dr = ret; > + devres_add(dev, dr); > + > + return ret; > +} > +EXPORT_SYMBOL_GPL(devm_i2c_new_dummy); > + > /** > * i2c_new_secondary_device - Helper to get the instantiated secondary address > * and create the associated device > diff --git a/include/linux/i2c.h b/include/linux/i2c.h > index d501d395..d0c091e6 100644 > --- a/include/linux/i2c.h > +++ b/include/linux/i2c.h > @@ -381,6 +381,9 @@ extern int i2c_probe_func_quick_read(struct i2c_adapter *, unsigned short addr); > extern struct i2c_client * > i2c_new_dummy(struct i2c_adapter *adap, u16 address); > > +extern struct i2c_client * > +devm_i2c_new_dummy(struct device *dev, struct i2c_adapter *adap, u16 address); > + > extern struct i2c_client * > i2c_new_secondary_device(struct i2c_client *client, > const char *name, >
Am 23.08.2017 um 14:09 schrieb Peter Rosin: > On 2017-08-22 07:45, Heiner Kallweit wrote: >> i2c_new_dummy is typically called from the probe function of the >> driver for the primary i2c client. It requires calls to >> i2c_unregister_device in the error path of the probe function and >> in the remove function. >> This can be simplified by introducing a device-managed version. >> >> Note the changed error case return value type: >> i2c_new_dummy returns NULL whilst devm_new_i2c_dummy returns an ERR_PTR. >> >> Signed-off-by: Heiner Kallweit <hkallweit1@gmail.com> > > Looks good to me, assuming you have some user in the wings... > I will use it in at24 I2C EEPROM driver. Some patches from me are pending already, switching to devm_i2c_new_dummy will be one of the next. Thanks, Heiner > Reviewed-by: Peter Rosin <peda@axentia.se> > > Cheers, > peda > >> --- >> v2: >> - added entry to Documentation/driver-model/devres.txt >> - extended documentation of new function >> - changed return value type to an ERR_PTR in case of error >> --- >> Documentation/driver-model/devres.txt | 3 +++ >> drivers/i2c/i2c-core-base.c | 39 +++++++++++++++++++++++++++++++++++ >> include/linux/i2c.h | 3 +++ >> 3 files changed, 45 insertions(+) >> >> diff --git a/Documentation/driver-model/devres.txt b/Documentation/driver-model/devres.txt >> index 30e04f7a..67d59528 100644 >> --- a/Documentation/driver-model/devres.txt >> +++ b/Documentation/driver-model/devres.txt >> @@ -258,6 +258,9 @@ GPIO >> devm_gpio_request_one() >> devm_gpio_free() >> >> +I2C >> + devm_i2c_new_dummy >> + >> IIO >> devm_iio_device_alloc() >> devm_iio_device_free() >> diff --git a/drivers/i2c/i2c-core-base.c b/drivers/i2c/i2c-core-base.c >> index 12822a4b..aac9491c 100644 >> --- a/drivers/i2c/i2c-core-base.c >> +++ b/drivers/i2c/i2c-core-base.c >> @@ -868,6 +868,45 @@ struct i2c_client *i2c_new_dummy(struct i2c_adapter *adapter, u16 address) >> } >> EXPORT_SYMBOL_GPL(i2c_new_dummy); >> >> +static void devm_i2c_release_dummy(struct device *dev, void *res) >> +{ >> + i2c_unregister_device(*(struct i2c_client **)res); >> +} >> + >> +/** >> + * devm_i2c_new_dummy - return a new i2c device bound to a dummy driver >> + * @dev: device the managed resource is bound to >> + * @adapter: the adapter managing the device >> + * @address: seven bit address to be used >> + * Context: can sleep >> + * >> + * This is the device-managed version of i2c_new_dummy. >> + * Note the changed return value type: It returns the new i2c client >> + * or an ERR_PTR in case of an error. >> + */ >> +struct i2c_client *devm_i2c_new_dummy(struct device *dev, >> + struct i2c_adapter *adapter, >> + u16 address) >> +{ >> + struct i2c_client *ret, **dr; >> + >> + dr = devres_alloc(devm_i2c_release_dummy, sizeof(*dr), GFP_KERNEL); >> + if (!dr) >> + return ERR_PTR(-ENOMEM); >> + >> + ret = i2c_new_dummy(adapter, address); >> + if (!ret) { >> + devres_free(dr); >> + return ERR_PTR(-EBUSY); >> + } >> + >> + *dr = ret; >> + devres_add(dev, dr); >> + >> + return ret; >> +} >> +EXPORT_SYMBOL_GPL(devm_i2c_new_dummy); >> + >> /** >> * i2c_new_secondary_device - Helper to get the instantiated secondary address >> * and create the associated device >> diff --git a/include/linux/i2c.h b/include/linux/i2c.h >> index d501d395..d0c091e6 100644 >> --- a/include/linux/i2c.h >> +++ b/include/linux/i2c.h >> @@ -381,6 +381,9 @@ extern int i2c_probe_func_quick_read(struct i2c_adapter *, unsigned short addr); >> extern struct i2c_client * >> i2c_new_dummy(struct i2c_adapter *adap, u16 address); >> >> +extern struct i2c_client * >> +devm_i2c_new_dummy(struct device *dev, struct i2c_adapter *adap, u16 address); >> + >> extern struct i2c_client * >> i2c_new_secondary_device(struct i2c_client *client, >> const char *name, >> > >
diff --git a/Documentation/driver-model/devres.txt b/Documentation/driver-model/devres.txt index 30e04f7a..67d59528 100644 --- a/Documentation/driver-model/devres.txt +++ b/Documentation/driver-model/devres.txt @@ -258,6 +258,9 @@ GPIO devm_gpio_request_one() devm_gpio_free() +I2C + devm_i2c_new_dummy + IIO devm_iio_device_alloc() devm_iio_device_free() diff --git a/drivers/i2c/i2c-core-base.c b/drivers/i2c/i2c-core-base.c index 12822a4b..aac9491c 100644 --- a/drivers/i2c/i2c-core-base.c +++ b/drivers/i2c/i2c-core-base.c @@ -868,6 +868,45 @@ struct i2c_client *i2c_new_dummy(struct i2c_adapter *adapter, u16 address) } EXPORT_SYMBOL_GPL(i2c_new_dummy); +static void devm_i2c_release_dummy(struct device *dev, void *res) +{ + i2c_unregister_device(*(struct i2c_client **)res); +} + +/** + * devm_i2c_new_dummy - return a new i2c device bound to a dummy driver + * @dev: device the managed resource is bound to + * @adapter: the adapter managing the device + * @address: seven bit address to be used + * Context: can sleep + * + * This is the device-managed version of i2c_new_dummy. + * Note the changed return value type: It returns the new i2c client + * or an ERR_PTR in case of an error. + */ +struct i2c_client *devm_i2c_new_dummy(struct device *dev, + struct i2c_adapter *adapter, + u16 address) +{ + struct i2c_client *ret, **dr; + + dr = devres_alloc(devm_i2c_release_dummy, sizeof(*dr), GFP_KERNEL); + if (!dr) + return ERR_PTR(-ENOMEM); + + ret = i2c_new_dummy(adapter, address); + if (!ret) { + devres_free(dr); + return ERR_PTR(-EBUSY); + } + + *dr = ret; + devres_add(dev, dr); + + return ret; +} +EXPORT_SYMBOL_GPL(devm_i2c_new_dummy); + /** * i2c_new_secondary_device - Helper to get the instantiated secondary address * and create the associated device diff --git a/include/linux/i2c.h b/include/linux/i2c.h index d501d395..d0c091e6 100644 --- a/include/linux/i2c.h +++ b/include/linux/i2c.h @@ -381,6 +381,9 @@ extern int i2c_probe_func_quick_read(struct i2c_adapter *, unsigned short addr); extern struct i2c_client * i2c_new_dummy(struct i2c_adapter *adap, u16 address); +extern struct i2c_client * +devm_i2c_new_dummy(struct device *dev, struct i2c_adapter *adap, u16 address); + extern struct i2c_client * i2c_new_secondary_device(struct i2c_client *client, const char *name,
i2c_new_dummy is typically called from the probe function of the driver for the primary i2c client. It requires calls to i2c_unregister_device in the error path of the probe function and in the remove function. This can be simplified by introducing a device-managed version. Note the changed error case return value type: i2c_new_dummy returns NULL whilst devm_new_i2c_dummy returns an ERR_PTR. Signed-off-by: Heiner Kallweit <hkallweit1@gmail.com> --- v2: - added entry to Documentation/driver-model/devres.txt - extended documentation of new function - changed return value type to an ERR_PTR in case of error --- Documentation/driver-model/devres.txt | 3 +++ drivers/i2c/i2c-core-base.c | 39 +++++++++++++++++++++++++++++++++++ include/linux/i2c.h | 3 +++ 3 files changed, 45 insertions(+)