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| author | Stefan Brüns <stefan.bruens@rwth-aachen.de> | 2015-08-23 16:06:30 +0200 |
|---|---|---|
| committer | Mark Brown <broonie@kernel.org> | 2015-08-26 18:58:29 +0100 |
| commit | 63ab645f4d8b2dc1351c41751e7ebb1b3f1c99d3 (patch) | |
| tree | 8188f47312a99fd8c04ee233c1f94d7c943cfd1e /drivers/spi/spi.c | |
| parent | 7dc9fbc342deb2e2658ebdecb5ffd7ff57945a66 (diff) | |
| download | linux-stable-63ab645f4d8b2dc1351c41751e7ebb1b3f1c99d3.tar.gz linux-stable-63ab645f4d8b2dc1351c41751e7ebb1b3f1c99d3.tar.bz2 linux-stable-63ab645f4d8b2dc1351c41751e7ebb1b3f1c99d3.zip | |
spi: check bits_per_word in spi_setup
This allows drivers for devices connected via SPI to check if the
controller supports a given bits_per_word value during setup.
Currently any BPW value is accepted durings setup, and transfers
are rejected later.
Signed-off-by: Stefan Brüns <stefan.bruens@rwth-aachen.de>
Signed-off-by: Mark Brown <broonie@kernel.org>
Diffstat (limited to 'drivers/spi/spi.c')
| -rw-r--r-- | drivers/spi/spi.c | 27 |
1 files changed, 19 insertions, 8 deletions
diff --git a/drivers/spi/spi.c b/drivers/spi/spi.c index 637d892b316d..829323ce7cdf 100644 --- a/drivers/spi/spi.c +++ b/drivers/spi/spi.c @@ -1740,6 +1740,20 @@ EXPORT_SYMBOL_GPL(spi_busnum_to_master); * other core methods are currently defined as inline functions. */ +static int __spi_validate_bits_per_word(struct spi_master *master, u8 bits_per_word) +{ + if (master->bits_per_word_mask) { + /* Only 32 bits fit in the mask */ + if (bits_per_word > 32) + return -EINVAL; + if (!(master->bits_per_word_mask & + SPI_BPW_MASK(bits_per_word))) + return -EINVAL; + } + + return 0; +} + /** * spi_setup - setup SPI mode and clock rate * @spi: the device whose settings are being modified @@ -1798,6 +1812,9 @@ int spi_setup(struct spi_device *spi) if (!spi->bits_per_word) spi->bits_per_word = 8; + if (__spi_validate_bits_per_word(spi->master, spi->bits_per_word)) + return -EINVAL; + if (!spi->max_speed_hz) spi->max_speed_hz = spi->master->max_speed_hz; @@ -1867,14 +1884,8 @@ static int __spi_validate(struct spi_device *spi, struct spi_message *message) xfer->speed_hz > master->max_speed_hz) xfer->speed_hz = master->max_speed_hz; - if (master->bits_per_word_mask) { - /* Only 32 bits fit in the mask */ - if (xfer->bits_per_word > 32) - return -EINVAL; - if (!(master->bits_per_word_mask & - BIT(xfer->bits_per_word - 1))) - return -EINVAL; - } + if (__spi_validate_bits_per_word(master, xfer->bits_per_word)) + return -EINVAL; /* * SPI transfer length should be multiple of SPI word size |