[PATCH 1/3] spi: core: Add devm_spi_alloc_master
From: Maxime Ripard <hidden>
Date: 2014-01-31 10:25:21
Also in:
linux-spi, lkml
Subsystem:
spi subsystem, the rest · Maintainers:
Mark Brown, Linus Torvalds
Using devm_spi_register_master leads to a memory leak on the spi_master structure. spi_alloc_master uses kzalloc to allocate the spi_master but the introduction of devm_spi_register_master removed all the matching calls to spi_master_put, leaking the spi_master structure. Add a devm_spi_alloc_master to provide the intended behaviour. Signed-off-by: Maxime Ripard <redacted> --- drivers/spi/spi.c | 36 ++++++++++++++++++++++++++++++++++++ include/linux/spi/spi.h | 2 ++ 2 files changed, 38 insertions(+)
diff --git a/drivers/spi/spi.c b/drivers/spi/spi.c
index 63613a9..eb728ec 100644
--- a/drivers/spi/spi.c
+++ b/drivers/spi/spi.c@@ -1266,6 +1266,42 @@ struct spi_master *spi_alloc_master(struct device *dev, unsigned size) } EXPORT_SYMBOL_GPL(spi_alloc_master); +static void devm_spi_put(struct device *dev, void *res) +{ + spi_master_put(*(struct spi_master **)res); +} + +/** + * devm_spi_alloc_master - allocate SPI master controller + * @dev: the controller, possibly using the platform_bus + * @size: how much zeroed driver-private data to allocate; the pointer to this + * memory is in the driver_data field of the returned device, + * accessible with spi_master_get_devdata(). + * Context: can sleep + * + * Allocates a master controller as with spi_alloc_master() which will + * automatically be freed + */ +struct spi_master *devm_spi_alloc_master(struct device *dev, unsigned size) +{ + struct spi_master **ptr, *master; + + ptr = devres_alloc(devm_spi_put, sizeof(*ptr), GFP_KERNEL); + if (!ptr) + return NULL; + + master = spi_alloc_master(dev, size); + if (master) { + *ptr = master; + devres_add(dev, ptr); + } else { + devres_free(ptr); + } + + return master; +} +EXPORT_SYMBOL_GPL(devm_spi_alloc_master); + #ifdef CONFIG_OF static int of_spi_register_master(struct spi_master *master) {
diff --git a/include/linux/spi/spi.h b/include/linux/spi/spi.h
index a1d4ca2..6fbdb2b 100644
--- a/include/linux/spi/spi.h
+++ b/include/linux/spi/spi.h@@ -462,6 +462,8 @@ extern void spi_finalize_current_transfer(struct spi_master *master); /* the spi driver core manages memory for the spi_master classdev */ extern struct spi_master * spi_alloc_master(struct device *host, unsigned size); +extern struct spi_master * +devm_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,
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1.8.4.2