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: Mark Brown <broonie@linaro.org>
This commit is contained in:
Mark Brown 2013-08-31 18:50:52 +01:00
parent 272b98c645
commit 666d5b4c74
3 changed files with 40 additions and 0 deletions

View file

@ -302,3 +302,6 @@ PHY
SLAVE DMA ENGINE
devm_acpi_dma_controller_register()
SPI
devm_spi_register_master()

View file

@ -1245,6 +1245,41 @@ done:
}
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));

View file

@ -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);