Commit 666d5b4c authored by Mark Brown's avatar Mark Brown
Browse files

spi: core: Add devm_spi_register_master() 



Help simplify the cleanup code for SPI master drivers by providing a
managed master registration function, ensuring that the master is
automatically unregistered whenever the device is unbound.

Signed-off-by: default avatarMark Brown <broonie@linaro.org>
parent 272b98c6

Documentation/driver-model/devres.txt

+3 −0
Original line number Diff line number Diff line
@@ -302,3 +302,6 @@ PHY 


SLAVE DMA ENGINE

  devm_acpi_dma_controller_register()



SPI

  devm_spi_register_master()

drivers/spi/spi.c

+35 −0
Original line number Diff line number Diff line
@@ -1245,6 +1245,41 @@ int spi_register_master(struct spi_master *master) 
}

EXPORT_SYMBOL_GPL(spi_register_master);



static void devm_spi_unregister(struct device *dev, void *res)

{

	spi_unregister_master(*(struct spi_master **)res);

}



/**

 * dev_spi_register_master - register managed SPI master controller

 * @dev:    device managing SPI master

 * @master: initialized master, originally from spi_alloc_master()

 * Context: can sleep

 *

 * Register a SPI device as with spi_register_master() which will

 * automatically be unregister

 */

int devm_spi_register_master(struct device *dev, struct spi_master *master)

{

	struct spi_master **ptr;

	int ret;



	ptr = devres_alloc(devm_spi_unregister, sizeof(*ptr), GFP_KERNEL);

	if (!ptr)

		return -ENOMEM;



	ret = spi_register_master(master);

	if (ret != 0) {

		*ptr = master;

		devres_add(dev, ptr);

	} else {

		devres_free(ptr);

	}



	return ret;

}

EXPORT_SYMBOL_GPL(devm_spi_register_master);



static int __unregister(struct device *dev, void *null)

{

	spi_unregister_device(to_spi_device(dev));

include/linux/spi/spi.h

+2 −0
Original line number Diff line number Diff line
@@ -434,6 +434,8 @@ extern struct spi_master * 
spi_alloc_master(struct device *host, unsigned size);



extern int spi_register_master(struct spi_master *master);

extern int devm_spi_register_master(struct device *dev,

				    struct spi_master *master);

extern void spi_unregister_master(struct spi_master *master);



extern struct spi_master *spi_busnum_to_master(u16 busnum);