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| author | Alexandru Ardelean <alexandru.ardelean@analog.com> | 2019-09-26 12:51:35 +0200 |
|---|---|---|
| committer | Mark Brown <broonie@kernel.org> | 2019-10-15 12:44:10 +0200 |
| commit | 6c613f68aabf33385c01e949204ac5ed30887161 (patch) | |
| tree | 7c1d71fe3b8d7f6c63453a873c952c5719934895 /drivers/spi/spi.c | |
| parent | spi: spidev: use new `word_delay` field for spi transfers (diff) | |
| download | linux-6c613f68aabf33385c01e949204ac5ed30887161.tar.xz linux-6c613f68aabf33385c01e949204ac5ed30887161.zip | |
spi: core,atmel: convert `word_delay_usecs` -> `word_delay` for spi_device
This change does a conversion from the `word_delay_usecs` -> `word_delay`
for the `spi_device` struct.
This allows users to specify inter-word delays in other unit types
(nano-seconds or clock cycles), depending on how users want.
The Atmel SPI driver is the only current user of the `word_delay_usecs`
field (from the `spi_device` struct).
So, it needed a slight conversion to use the `word_delay` as an `spi_delay`
struct.
In SPI core, the only required mechanism is to update the `word_delay`
information per `spi_transfer`. This requires a bit more logic than before,
because it needs that both delays be converted to a common unit
(nano-seconds) for comparison.
Signed-off-by: Alexandru Ardelean <alexandru.ardelean@analog.com>
Link: https://lore.kernel.org/r/20190926105147.7839-8-alexandru.ardelean@analog.com
Signed-off-by: Mark Brown <broonie@kernel.org>
Diffstat (limited to 'drivers/spi/spi.c')
| -rw-r--r-- | drivers/spi/spi.c | 24 |
1 files changed, 22 insertions, 2 deletions
diff --git a/drivers/spi/spi.c b/drivers/spi/spi.c index b69c14082c52..307e440dd92d 100644 --- a/drivers/spi/spi.c +++ b/drivers/spi/spi.c @@ -3281,6 +3281,26 @@ void spi_set_cs_timing(struct spi_device *spi, u8 setup, u8 hold, } EXPORT_SYMBOL_GPL(spi_set_cs_timing); +static int _spi_xfer_word_delay_update(struct spi_transfer *xfer, + struct spi_device *spi) +{ + int delay1, delay2; + + delay1 = _spi_delay_to_ns(&xfer->word_delay, xfer); + if (delay1 < 0) + return delay1; + + delay2 = _spi_delay_to_ns(&spi->word_delay, xfer); + if (delay2 < 0) + return delay2; + + if (delay1 < delay2) + memcpy(&xfer->word_delay, &spi->word_delay, + sizeof(xfer->word_delay)); + + return 0; +} + static int __spi_validate(struct spi_device *spi, struct spi_message *message) { struct spi_controller *ctlr = spi->controller; @@ -3416,8 +3436,8 @@ static int __spi_validate(struct spi_device *spi, struct spi_message *message) return -EINVAL; } - if (xfer->word_delay_usecs < spi->word_delay_usecs) - xfer->word_delay_usecs = spi->word_delay_usecs; + if (_spi_xfer_word_delay_update(xfer, spi)) + return -EINVAL; } message->status = -EINPROGRESS; |