On 02.08.2020 20:05, Wolfram Sang wrote:
> On Fri, Jun 19, 2020 at 05:19:03PM +0300, Codrin Ciubotariu wrote:
>> Even if I2C bus GPIO recovery is optional, devm_gpiod_get() can return
>> -EPROBE_DEFER, so we should at least treat that. This ends up with
>> i2c_register_adapter() to be able to return -EPROBE_DEFER.
>>
>> Signed-off-by: Codrin Ciubotariu <codrin.ciubotariu@xxxxxxxxxxxxx>
>> ---
>> drivers/i2c/i2c-core-base.c | 22 ++++++++++++++++------
>> 1 file changed, 16 insertions(+), 6 deletions(-)
>>
>> diff --git a/drivers/i2c/i2c-core-base.c b/drivers/i2c/i2c-core-base.c
>> index 4ee29fec4e93..f8d9f2048ca8 100644
>> --- a/drivers/i2c/i2c-core-base.c
>> +++ b/drivers/i2c/i2c-core-base.c
>> @@ -368,15 +368,16 @@ static int i2c_gpio_init_recovery(struct i2c_adapter *adap)
>> return i2c_gpio_init_generic_recovery(adap);
>> }
>>
>> -static void i2c_init_recovery(struct i2c_adapter *adap)
>> +static int i2c_init_recovery(struct i2c_adapter *adap)
>> {
>> struct i2c_bus_recovery_info *bri = adap->bus_recovery_info;
>> char *err_str;
>>
>> if (!bri)
>> - return;
>> + return 0;
>>
>> - i2c_gpio_init_recovery(adap);
>> + if (i2c_gpio_init_recovery(adap) == -EPROBE_DEFER)
>> + return -EPROBE_DEFER;
>>
>> if (!bri->recover_bus) {
>> err_str = "no recover_bus() found";
>> @@ -392,7 +393,7 @@ static void i2c_init_recovery(struct i2c_adapter *adap)
>> if (gpiod_get_direction(bri->sda_gpiod) == 0)
>> bri->set_sda = set_sda_gpio_value;
>> }
>> - return;
>> + return 0;
>
> This is correct but I think the code flow is/was confusing. Can you drop
> this 'return' and use 'else if' for the next code block? I think this is
> more readable.
Ok, it makes sense. Should I make a separate patch for this only?
One more question, should we keep:
if (!bri->set_sda && !bri->get_sda) {
err_str = "either get_sda() or set_sda() needed";
goto err;
}
?
Without {get/set}_sda we won't be able to generate stop commands and
possibly check if the bus is free, but we can still generate the SCL
clock pulses.
>
>> }
>>
>> if (bri->recover_bus == i2c_generic_scl_recovery) {
>> @@ -407,10 +408,12 @@ static void i2c_init_recovery(struct i2c_adapter *adap)
>> }
>> }
>>
>> - return;
>> + return 0;
>> err:
>> dev_err(&adap->dev, "Not using recovery: %s\n", err_str);
>> adap->bus_recovery_info = NULL;
>> +
>> + return 0;
>
> 'return -EINVAL;' I'd suggest.
OK
>
>> }
>>
>> static int i2c_smbus_host_notify_to_irq(const struct i2c_client *client)
>> @@ -1476,7 +1479,9 @@ static int i2c_register_adapter(struct i2c_adapter *adap)
>> "Failed to create compatibility class link\n");
>> #endif
>>
>> - i2c_init_recovery(adap);
>> + res = i2c_init_recovery(adap);
>> + if (res == -EPROBE_DEFER)
>> + goto out_link;
>
> Please move 'i2c_init_recovery' above the class-link creation. It
> shouldn't make a difference but we can skip the extra label and the
> ifdeffery.
Ok. Perhaps I should also move the debug print with the registered
adapter after calling i2c_init_recovery().
>
>>
>> /* create pre-declared device nodes */
>> of_i2c_register_devices(adap);
>> @@ -1493,6 +1498,11 @@ static int i2c_register_adapter(struct i2c_adapter *adap)
>>
>> return 0;
>>
>> +out_link:
>> +#ifdef CONFIG_I2C_COMPAT
>> + class_compat_remove_link(i2c_adapter_compat_class, &adap->dev,
>> + adap->dev.parent);
>> +#endif
>> out_reg:
>> init_completion(&adap->dev_released);
>> device_unregister(&adap->dev);
>> --
>> 2.25.1
>>
Do you want me to integrate this patch in the previous one?
Best regards,
Codrin
