> On Mar 29, 2021, at 11:18 AM, Greg KH <gregkh@xxxxxxxxxxxxxxxxxxx> wrote:
>
> On Mon, Mar 29, 2021 at 03:40:35PM +0000, Annaliese McDermond wrote:
>> A test was added to the probe function to ensure the device was
>> actually connected and working before successfully completing a
>> probe. If the device was actually there, but the I2C bus was not
>> ready yet for whatever reason, the probe fails permanently.
>>
>> Change the probe so that we defer the probe on a regmap read
>> failure so that we try the probe again when the dependent drivers
>> are potentially loaded. This should not affect the case where the
>> device truly isn't present because the probe will never successfully
>> complete.
>>
>> Fixes: 2aa916e ("sc16is7xx: Read the LSR register for basic device presence check")
>
> Please use the full 12 characters of the git commit id, as the
> documentation asks for. This should be:
>
> Fixes: 2aa916e67db3 ("sc16is7xx: Read the LSR register for basic device presence check")
I’m sorry, I must have missed the section specifying that, and since I saw commits like
05962f95f9ac specifying 7 characters in their “fixes” line, I made the assumption that
this was the correct length.
Would you like me to post a v2 patch with the hash changed?
>> Cc: stable@xxxxxxxxxxxxxxx
>> Signed-off-by: Annaliese McDermond <nh6z@xxxxxxxx>
>> ---
>> drivers/tty/serial/sc16is7xx.c | 2 +-
>> 1 file changed, 1 insertion(+), 1 deletion(-)
>>
>> diff --git a/drivers/tty/serial/sc16is7xx.c b/drivers/tty/serial/sc16is7xx.c
>> index f86ec2d2635b..9adb8362578c 100644
>> --- a/drivers/tty/serial/sc16is7xx.c
>> +++ b/drivers/tty/serial/sc16is7xx.c
>> @@ -1196,7 +1196,7 @@ static int sc16is7xx_probe(struct device *dev,
>> ret = regmap_read(regmap,
>> SC16IS7XX_LSR_REG << SC16IS7XX_REG_SHIFT, &val);
>> if (ret < 0)
>> - return ret;
>> + return -EPROBE_DEFER;
>>
>> /* Alloc port structure */
>> s = devm_kzalloc(dev, struct_size(s, p, devtype->nr_uart), GFP_KERNEL);
>> --
>> 2.27.0
>
> Any reason you did not cc: the tty maintainer with this change?
None other than I believed “serial drivers” to be more specific than “tty layer” when
looking at the maintainers. I’m happy to Cc Jiri if needed.
>
> thanks,
>
> greg k-h
-- Anna
