diff options
| author |   Pelle Nilsson <per.nilsson@xelmo.com> | 2015-04-14 15:40:17 +0200 |
|---|---|---|
| committer |   Mark Brown <broonie@kernel.org> | 2015-04-18 12:01:03 +0100 |
| commit | 7d0ec8b6f40b356f780b79de63eeafd6b907d68c (patch) | |
| tree | 669ce3a25a14487c4dd0bb08839719e89245ca9c /drivers/spi | |
| parent | Linux 4.0-rc1 (diff) | |
| download | linux-dev-7d0ec8b6f40b356f780b79de63eeafd6b907d68c.tar.xz linux-dev-7d0ec8b6f40b356f780b79de63eeafd6b907d68c.zip | |
spi: bitbang: Make setup_transfer() callback optional
Some controller drivers have no need of this callback (spi-altera even
causes a NULL pointer dereference because it doesn't register the callback,
falsely assuming that it is already optional).
Fixes: 30af9b558a56 ("spi/bitbang: Drop empty setup() functions")
Signed-off-by: Pelle Nilsson <per.nilsson@xelmo.com>
Reviewed-by: Ezequiel Garcia <ezequiel.garcia@vanguardiasur.com.ar>
Signed-off-by: Mark Brown <broonie@kernel.org>
Diffstat (limited to 'drivers/spi')
| -rw-r--r-- | drivers/spi/spi-bitbang.c | 17 |
1 files changed, 10 insertions, 7 deletions
diff --git a/drivers/spi/spi-bitbang.c b/drivers/spi/spi-bitbang.c index 5ef6638d5e8a..840a4984d365 100644 --- a/drivers/spi/spi-bitbang.c +++ b/drivers/spi/spi-bitbang.c @@ -180,7 +180,6 @@ int spi_bitbang_setup(struct spi_device *spi) { struct spi_bitbang_cs *cs = spi->controller_state; struct spi_bitbang *bitbang; - int retval; unsigned long flags; bitbang = spi_master_get_devdata(spi->master); @@ -197,9 +196,11 @@ int spi_bitbang_setup(struct spi_device *spi) if (!cs->txrx_word) return -EINVAL; - retval = bitbang->setup_transfer(spi, NULL); - if (retval < 0) - return retval; + if (bitbang->setup_transfer) { + int retval = bitbang->setup_transfer(spi, NULL); + if (retval < 0) + return retval; + } dev_dbg(&spi->dev, "%s, %u nsec/bit\n", __func__, 2 * cs->nsecs); @@ -295,9 +296,11 @@ static int spi_bitbang_transfer_one(struct spi_master *master, /* init (-1) or override (1) transfer params */ if (do_setup != 0) { - status = bitbang->setup_transfer(spi, t); - if (status < 0) - break; + if (bitbang->setup_transfer) { + status = bitbang->setup_transfer(spi, t); + if (status < 0) + break; + } if (do_setup == -1) do_setup = 0; } |