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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>
This commit is contained in:
Stefan Roese 2014-01-31 13:44:59 +01:00 committed by Mark Brown
parent 38dbfb59d1
commit 4302a59629
1 changed files with 15 additions and 5 deletions
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20
drivers/spi/spi-fsl-spi.c
View File

@ -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;
/* 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 ((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 = 0;
status = -EINVAL;
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 */
status = -EINVAL;
if (cs_change)
status = fsl_spi_setup_transfer(spi, t);
if (status < 0)