diff options
| author | Mark Brown <broonie@linaro.org> | 2013-07-10 17:57:26 +0400 |
|---|---|---|
| committer | Mark Brown <broonie@linaro.org> | 2013-07-15 14:34:51 +0400 |
| commit | a2fd4f9fa3b9f051550b36c4dfa74bc32bda24ee (patch) | |
| tree | b317a65457403d0e3175cd3fa36a66b6b2627527 | |
| parent | ad81f0545ef01ea651886dddac4bef6cec930092 (diff) | |
| download | linux-a2fd4f9fa3b9f051550b36c4dfa74bc32bda24ee.tar.xz | |
spi: Support transfer speed checking in the core
Allow drivers to avoid implementing their own checks for simple rates by
specifying the limits in the master structure.
Signed-off-by: Mark Brown <broonie@linaro.org>
| -rw-r--r-- | drivers/spi/spi.c | 7 | ||||
| -rw-r--r-- | include/linux/spi/spi.h | 6 |
2 files changed, 13 insertions, 0 deletions
diff --git a/drivers/spi/spi.c b/drivers/spi/spi.c index 978dda2c5239..a52f16685d6a 100644 --- a/drivers/spi/spi.c +++ b/drivers/spi/spi.c @@ -1387,6 +1387,13 @@ static int __spi_async(struct spi_device *spi, struct spi_message *message) BIT(xfer->bits_per_word - 1))) return -EINVAL; } + + if (xfer->speed_hz && master->min_speed_hz && + xfer->speed_hz < master->min_speed_hz) + return -EINVAL; + if (xfer->speed_hz && master->max_speed_hz && + xfer->speed_hz > master->max_speed_hz) + return -EINVAL; } message->spi = spi; diff --git a/include/linux/spi/spi.h b/include/linux/spi/spi.h index 28e440be1c07..cdf668156154 100644 --- a/include/linux/spi/spi.h +++ b/include/linux/spi/spi.h @@ -233,6 +233,8 @@ static inline void spi_unregister_driver(struct spi_driver *sdrv) * suported. If set, the SPI core will reject any transfer with an * unsupported bits_per_word. If not set, this value is simply ignored, * and it's up to the individual driver to perform any validation. + * @min_speed_hz: Lowest supported transfer speed + * @max_speed_hz: Highest supported transfer speed * @flags: other constraints relevant to this driver * @bus_lock_spinlock: spinlock for SPI bus locking * @bus_lock_mutex: mutex for SPI bus locking @@ -312,6 +314,10 @@ struct spi_master { #define SPI_BIT_MASK(bits) (((bits) == 32) ? ~0UL : (BIT(bits) - 1)) #define SPI_BPW_RANGE_MASK(min, max) (SPI_BIT_MASK(max) - SPI_BIT_MASK(min - 1)) + /* limits on transfer speed */ + u32 min_speed_hz; + u32 max_speed_hz; + /* other constraints relevant to this driver */ u16 flags; #define SPI_MASTER_HALF_DUPLEX BIT(0) /* can't do full duplex */ |