From 94c69f765f1b4a658d96905ec59928e3e3e07e6a Mon Sep 17 00:00:00 2001 From: Axel Lin Date: Tue, 10 Sep 2013 15:43:41 +0800 Subject: spi: bitbang: Let spi_bitbang_start() take a reference to master Many drivers that use bitbang library have a leak on probe error paths. This is because once a spi_master_get() call succeeds, we need an additional spi_master_put() call to free the memory. Fix this issue by moving the code taking a reference to master to spi_bitbang_start(), so spi_bitbang_start() will take a reference to master on success. With this change, the caller is responsible for calling spi_bitbang_stop() to decrement the reference and spi_master_put() as counterpart of spi_alloc_master() to prevent a memory leak. So now we have below patten for drivers using bitbang library: probe: spi_alloc_master -> Init reference count to 1 spi_bitbang_start -> Increment reference count remove: spi_bitbang_stop -> Decrement reference count spi_master_put -> Decrement reference count (reference count reaches 0) Fixup all users accordingly. Signed-off-by: Axel Lin Suggested-by: Uwe Kleine-Koenig Acked-by: Uwe Kleine-Koenig Signed-off-by: Mark Brown --- drivers/spi/spi-ppc4xx.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) (limited to 'drivers/spi/spi-ppc4xx.c') diff --git a/drivers/spi/spi-ppc4xx.c b/drivers/spi/spi-ppc4xx.c index 0ee53c25ba58..c57740bb70d3 100644 --- a/drivers/spi/spi-ppc4xx.c +++ b/drivers/spi/spi-ppc4xx.c @@ -396,7 +396,7 @@ static int spi_ppc4xx_of_probe(struct platform_device *op) master->dev.of_node = np; platform_set_drvdata(op, master); hw = spi_master_get_devdata(master); - hw->master = spi_master_get(master); + hw->master = master; hw->dev = dev; init_completion(&hw->done); @@ -558,6 +558,7 @@ static int spi_ppc4xx_of_remove(struct platform_device *op) free_irq(hw->irqnum, hw); iounmap(hw->regs); free_gpios(hw); + spi_master_put(master); return 0; } -- cgit v1.2.3