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| author | Axel Lin <axel.lin@ingics.com> | 2013-09-10 07:43:41 (GMT) |
|---|---|---|
| committer | Matthew Weigel <Matthew.Weigel@freescale.com> | 2014-12-11 18:37:36 (GMT) |
| commit | fa8d74c3d960b7aefe058cd74d50a3a124efb969 (patch) | |
| tree | 27f7c3a46635394da2130826a073ecdd98b9389b /drivers/spi/spi-lm70llp.c | |
| parent | 6ac66cdab994ddc32d1a7676620eee8be04ac1dc (diff) | |
| download | linux-fsl-qoriq-fa8d74c3d960b7aefe058cd74d50a3a124efb969.tar.xz | |
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 <axel.lin@ingics.com>
Suggested-by: Uwe Kleine-Koenig <u.kleine-koenig@pengutronix.de>
Acked-by: Uwe Kleine-Koenig <u.kleine-koenig@pengutronix.de>
Signed-off-by: Mark Brown <broonie@linaro.org>
(cherry picked from commit 94c69f765f1b4a658d96905ec59928e3e3e07e6a)
Change-Id: Ifce35be3f5b3a64cfbf8f42dcafa35134f039899
Reviewed-on: http://git.am.freescale.net:8181/20082
Tested-by: Review Code-CDREVIEW <CDREVIEW@freescale.com>
Reviewed-by: Zhengxiong Jin <Jason.Jin@freescale.com>
Diffstat (limited to 'drivers/spi/spi-lm70llp.c')
| -rw-r--r-- | drivers/spi/spi-lm70llp.c | 2 |
1 files changed, 1 insertions, 1 deletions
diff --git a/drivers/spi/spi-lm70llp.c b/drivers/spi/spi-lm70llp.c index 0759b5d..41c5765 100644 --- a/drivers/spi/spi-lm70llp.c +++ b/drivers/spi/spi-lm70llp.c @@ -222,7 +222,7 @@ static void spi_lm70llp_attach(struct parport *p) /* * SPI and bitbang hookup. */ - pp->bitbang.master = spi_master_get(master); + pp->bitbang.master = master; pp->bitbang.chipselect = lm70_chipselect; pp->bitbang.txrx_word[SPI_MODE_0] = lm70_txrx; pp->bitbang.flags = SPI_3WIRE; |