From: Fabio Estevam <fabio.estevam@xxxxxxxxxxxxx> Recently we have been seing some reports about PIO mode not working properly. - http://www.spinics.net/lists/linux-i2c/msg11985.html - http://marc.info/?l=linux-i2c&m=137235593101385&w=2 - https://lkml.org/lkml/2013/6/24/430 Let's use DMA mode even for small transfers. Without this patch, i2c reads the incorrect sgtl5000 version on a mx28evk when touchscreen is enabled: [ 5.856270] sgtl5000 0-000a: Device with ID register 0 is not a sgtl5000 [ 9.877307] sgtl5000 0-000a: ASoC: failed to probe CODEC -19 [ 9.883528] mxs-sgtl5000 sound.12: ASoC: failed to instantiate card -19 [ 9.892955] mxs-sgtl5000 sound.12: snd_soc_register_card failed (-19) Cc: <stable@xxxxxxxxxxxxxxx> Signed-off-by: Fabio Estevam <fabio.estevam@xxxxxxxxxxxxx> --- Applies against 3.10 Changes since v1: - Keep the PIO code drivers/i2c/busses/i2c-mxs.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/drivers/i2c/busses/i2c-mxs.c b/drivers/i2c/busses/i2c-mxs.c index 2039f23..6d8094d 100644 --- a/drivers/i2c/busses/i2c-mxs.c +++ b/drivers/i2c/busses/i2c-mxs.c @@ -494,7 +494,7 @@ static int mxs_i2c_xfer_msg(struct i2c_adapter *adap, struct i2c_msg *msg, * based on this empirical measurement and a lot of previous frobbing. */ i2c->cmd_err = 0; - if (msg->len < 8) { + if (0) { /* disable PIO mode until a proper fix is made */ ret = mxs_i2c_pio_setup_xfer(adap, msg, flags); if (ret) mxs_i2c_reset(i2c); -- 1.8.1.2 -- To unsubscribe from this list: send the line "unsubscribe linux-i2c" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html