lkml.org 
[lkml]   [2018]   [Aug]   [9]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
/
Date
From
SubjectRe: [PATCH v2 3/4] i2c: imx: Simplify stopped state tracking
On Thu, Aug 09, 2018 at 02:06:43PM +0200, Esben Haabendal wrote:
> Uwe Kleine-König <u.kleine-koenig@pengutronix.de> writes:
>
> > On Mon, Jul 09, 2018 at 11:43:03AM +0200, Esben Haabendal wrote:
> >> From: Esben Haabendal <eha@deif.com>
> >>
> >> Always update the stopped state when busy status have been checked.
> >> This is identical to what was done before, with the exception of error
> >> handling.
> >> Without this change, some errors cause the stopped state to be left in
> >> incorrect state in i2c_imx_stop(), i2c_imx_dma_read(), i2c_imx_read() and
> >> i2c_imx_xfer().
> >>
> >> Signed-off-by: Esben Haabendal <eha@deif.com>
> >> ---
> >> drivers/i2c/busses/i2c-imx.c | 12 ++++++------
> >> 1 file changed, 6 insertions(+), 6 deletions(-)
> >>
> >> diff --git a/drivers/i2c/busses/i2c-imx.c b/drivers/i2c/busses/i2c-imx.c
> >> index d86f152176a4..1db8e6790afc 100644
> >> --- a/drivers/i2c/busses/i2c-imx.c
> >> +++ b/drivers/i2c/busses/i2c-imx.c
> >> @@ -421,10 +421,14 @@ static int i2c_imx_bus_busy(struct imx_i2c_struct *i2c_imx, int for_busy)
> >> return -EAGAIN;
> >> }
> >>
> >> - if (for_busy && (temp & I2SR_IBB))
> >> + if (for_busy && (temp & I2SR_IBB)) {
> >> + i2c_imx->stopped = 0;
> >> break;
> >> - if (!for_busy && !(temp & I2SR_IBB))
> >> + }
> >> + if (!for_busy && !(temp & I2SR_IBB)) {
> >> + i2c_imx->stopped = 1;
> >> break;
> >> + }
> >
> > Would it make sense to assign to ->stopped independent of for_busy?
>
> What do you mean?
>
> Assigning to ->stopped on each check for I2SR_IBB in loop, independent
> of the for_busy argument? I don't think so. The additional assignments
> would be to the same value as it is set to already.

Currently you have:

if (for_busy && (temp & I2SR_IBB)) {
i2c_imx->stopped = 0;
break;
}

if (!for_busy && !(temp & I2SR_IBB)) {
i2c_imx->stopped = 1;
break;
}

The semantic of this is the same (apart from always updating .stopped)
but is imho easier:

i2c_imx->stopped = !(temp & I2SR_IBB);

if (for_busy != i2c_imx->stopped)
break;

Best regards
Uwe

--
Pengutronix e.K. | Uwe Kleine-König |
Industrial Linux Solutions | http://www.pengutronix.de/ |

\
 
 \ /
  Last update: 2018-08-09 18:27    [W:0.071 / U:4.180 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site