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>
diff --git a/drivers/spi/spi-fsl-spi.c b/drivers/spi/spi-fsl-spi.c
index 119f7af..4dcb292 100644
--- a/drivers/spi/spi-fsl-spi.c
+++ b/drivers/spi/spi-fsl-spi.c
@@ -362,18 +362,28 @@
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)