spi: core: make zero length transfer valid again

Zero length transfer becomes invalid since
"spi: core: Validate length of the transfers in message" commit,
but it should be valid to support an odd device, for example, which
requires long delay between chipselect and the first transfer, etc.

Signed-off-by: Atsushi Nemoto <anemo@mba.ocn.ne.jp>
Tested-by: Thierry Reding <treding@nvidia.com>
Signed-off-by: Mark Brown <broonie@linaro.org>
This commit is contained in:
Atsushi Nemoto 2014-02-28 23:03:16 +09:00 committed by Mark Brown
parent f97b26b05b
commit 6ea312936d
1 changed files with 2 additions and 3 deletions

View File

@ -1617,7 +1617,7 @@ static int __spi_validate(struct spi_device *spi, struct spi_message *message)
{
struct spi_master *master = spi->master;
struct spi_transfer *xfer;
int w_size, n_words;
int w_size;
if (list_empty(&message->transfers))
return -EINVAL;
@ -1680,9 +1680,8 @@ static int __spi_validate(struct spi_device *spi, struct spi_message *message)
else
w_size = 4;
n_words = xfer->len / w_size;
/* No partial transfers accepted */
if (!n_words || xfer->len % w_size)
if (xfer->len % w_size)
return -EINVAL;
if (xfer->speed_hz && master->min_speed_hz &&