| Message ID | 1363183063-24947-1-git-send-email-agust@denx.de (mailing list archive) |
|---|---|
| State | Superseded, archived |
| Headers | show |
On Mon, 1 Apr 2013 14:30:17 +0100 Mark Brown <broonie@opensource.wolfsonmicro.com> wrote: > On Wed, Mar 13, 2013 at 02:57:43PM +0100, Anatolij Gustschin wrote: > > Some SPI slave devices require asserted chip select signal across > > multiple transfer segments of an SPI message. Currently the driver > > This isn't some devices, it's the standard behaviour for the API - > drivers and frameworks can split up a SPI transfer into as many pieces > as amuses them. > > Anyway, applied. Thanks! Could you also apply this one ? https://patchwork.kernel.org/patch/2251911 Thanks, Anatolij ------------------------------------------------------------------------------ Own the Future-Intel® Level Up Game Demo Contest 2013 Rise to greatness in Intel's independent game demo contest. Compete for recognition, cash, and the chance to get your game on Steam. $5K grand prize plus 10 genre and skill prizes. Submit your demo by 6/6/13. http://p.sf.net/sfu/intel_levelupd2d
diff --git a/drivers/spi/spi-mpc512x-psc.c b/drivers/spi/spi-mpc512x-psc.c index 6b600a2..dfddf33 100644 --- a/drivers/spi/spi-mpc512x-psc.c +++ b/drivers/spi/spi-mpc512x-psc.c @@ -168,7 +168,7 @@ static int mpc512x_psc_spi_transfer_rxtx(struct spi_device *spi, for (i = count; i > 0; i--) { data = tx_buf ? *tx_buf++ : 0; - if (len == EOFBYTE) + if (len == EOFBYTE && t->cs_change) setbits32(&fifo->txcmd, MPC512x_PSC_FIFO_EOF); out_8(&fifo->txdata_8, data); len--;
Some SPI slave devices require asserted chip select signal across multiple transfer segments of an SPI message. Currently the driver always de-asserts the internal SS signal for every single transfer segment of the message and ignores the 'cs_change' flag of the transfer description. Disable the internal chip select (SS) only if this is needed and indicated by the 'cs_change' flag. Without this change, each partial transfer of a surrounding multi-part SPI transaction might erroneously change the SS signal, which might prevent slaves from answering the request that was sent in a previous transfer segment because the transaction could be considered aborted (SS was de-asserted before reading the response). Reported-by: Gerhard Sittig <gerhard.sittig@ifm.com> Signed-off-by: Anatolij Gustschin <agust@denx.de> --- drivers/spi/spi-mpc512x-psc.c | 2 +- 1 files changed, 1 insertions(+), 1 deletions(-)