diff options
| author | Stefan Roese <sr@denx.de> | 2014-01-31 16:44:59 +0400 |
|---|---|---|
| committer | Mark Brown <broonie@linaro.org> | 2014-02-04 15:33:39 +0400 |
| commit | 4302a59629f7a0bd70fd1605d2b558597517372a (patch) | |
| tree | 8472dcbd78ea55f7ff49796c1682c9542da94368 /drivers/spi/spi-fsl-spi.c | |
| parent | 38dbfb59d1175ef458d006556061adeaa8751b72 (diff) | |
| download | linux-4302a59629f7a0bd70fd1605d2b558597517372a.tar.xz | |
spi: fsl: Fix problem with multi message transfers
When used via spidev with more than one messages to tranfer via
SPI_IOC_MESSAGE the current implementation would return with
-EINVAL, since bits_per_word and speed_hz are set in all
transfer structs. And in the 2nd loop status will stay at
-EINVAL as its not overwritten again via fsl_spi_setup_transfer().
This patch changes this behavious by first checking if one of
the messages uses different settings. If this is the case
the function will return with -EINVAL. If not, the messages
are transferred correctly.
Signed-off-by: Stefan Roese <sr@denx.de>
Signed-off-by: Mark Brown <broonie@linaro.org>
Diffstat (limited to 'drivers/spi/spi-fsl-spi.c')
| -rw-r--r-- | drivers/spi/spi-fsl-spi.c | 20 |
1 files changed, 15 insertions, 5 deletions
diff --git a/drivers/spi/spi-fsl-spi.c b/drivers/spi/spi-fsl-spi.c index 119f7af94537..4dcb2929c01f 100644 --- a/drivers/spi/spi-fsl-spi.c +++ b/drivers/spi/spi-fsl-spi.c @@ -362,18 +362,28 @@ static int fsl_spi_bufs(struct spi_device *spi, struct spi_transfer *t, static void fsl_spi_do_one_msg(struct spi_message *m) { struct spi_device *spi = m->spi; - struct spi_transfer *t; + struct spi_transfer *t, *first; unsigned int cs_change; const int nsecs = 50; int status; - cs_change = 1; - status = 0; + /* Don't allow changes if CS is active */ + first = list_first_entry(&m->transfers, struct spi_transfer, + transfer_list); list_for_each_entry(t, &m->transfers, transfer_list) { - if (t->bits_per_word || t->speed_hz) { - /* Don't allow changes if CS is active */ + if ((first->bits_per_word != t->bits_per_word) || + (first->speed_hz != t->speed_hz)) { status = -EINVAL; + dev_err(&spi->dev, + "bits_per_word/speed_hz should be same for the same SPI transfer\n"); + return; + } + } + cs_change = 1; + status = -EINVAL; + list_for_each_entry(t, &m->transfers, transfer_list) { + if (t->bits_per_word || t->speed_hz) { if (cs_change) status = fsl_spi_setup_transfer(spi, t); if (status < 0) |