diff options
author | Fabio Estevam <fabio.estevam@freescale.com> | 2013-07-01 18:14:21 -0300 |
---|---|---|
committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2013-08-14 22:59:06 -0700 |
commit | 060a7c36d7ba82d7f520d7f328db5d38e99c20a4 (patch) | |
tree | 7f1ccae277d008588caf1f02ec1e88fa509703d6 | |
parent | 630d2243751d762ea9e1baabecd6536e9db8d0be (diff) |
i2c: i2c-mxs: Use DMA mode even for small transfers
commit d6e102f498cbcc8dd2e36721a01213f036397112 upstream.
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)
[wsa: we have a proper solution for -next, so this non intrusive
solution is OK for now]
Signed-off-by: Fabio Estevam <fabio.estevam@freescale.com>
Acked-by: Shawn Guo <shawn.guo@linaro.org>
Acked-by: Lucas Stach <l.stach@pengutronix.de>
Acked-by: Marek Vasut <marex@denx.de>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
-rw-r--r-- | drivers/i2c/busses/i2c-mxs.c | 2 |
1 files changed, 1 insertions, 1 deletions
diff --git a/drivers/i2c/busses/i2c-mxs.c b/drivers/i2c/busses/i2c-mxs.c index 2039f230482..6d8094d4498 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); |