Re: [PATCH v2 3/4] i2c: imx: Simplify stopped state tracking

From: Esben Haabendal
Date: Thu Aug 09 2018 - 08:06:50 EST


Uwe Kleine-KÃnig <u.kleine-koenig@xxxxxxxxxxxxxx> writes:

> On Mon, Jul 09, 2018 at 11:43:03AM +0200, Esben Haabendal wrote:
>> From: Esben Haabendal <eha@xxxxxxxx>
>>
>> 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@xxxxxxxx>
>> ---
>> 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.

>> if (time_after(jiffies, orig_jiffies + msecs_to_jiffies(500))) {
>> dev_dbg(&i2c_imx->adapter.dev,
>> "<%s> I2C bus is busy\n", __func__);
>> @@ -538,7 +542,6 @@ static int i2c_imx_start(struct imx_i2c_struct *i2c_imx)
>> result = i2c_imx_bus_busy(i2c_imx, 1);
>> if (result)
>> return result;
>> - i2c_imx->stopped = 0;
>>
>> temp |= I2CR_IIEN | I2CR_MTX | I2CR_TXAK;
>> temp &= ~I2CR_DMAEN;
>> @@ -569,7 +572,6 @@ static void i2c_imx_stop(struct imx_i2c_struct *i2c_imx)
>>
>> if (!i2c_imx->stopped) {
>> i2c_imx_bus_busy(i2c_imx, 0);
>> - i2c_imx->stopped = 1;
>> }
>
> The braces can go away here.

Will do.

/Esben