Am Montag, den 01.07.2013, 18:14 -0300 schrieb Fabio Estevam: > 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); I still plan to take another look at the PIO mode, but higher priority things keep popping up in front of me. So this patch is: Acked-by: Lucas Stach <l.stach@xxxxxxxxxxxxxx> -- Pengutronix e.K. | Lucas Stach | Industrial Linux Solutions | http://www.pengutronix.de/ | Peiner Str. 6-8, 31137 Hildesheim, Germany | Phone: +49-5121-206917-5076 | Amtsgericht Hildesheim, HRA 2686 | Fax: +49-5121-206917-5555 | -- 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
