Re: Re: [RFC PATCH 3/4] i2c: core: treat EPROBE_DEFER when acquiring SCL/SDA GPIOs
> > 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?
I am fine if this is included in this change.
> 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.
My gut feeling says we need to keep it. I can't recall the reason now
and want to send out this answer ASAP. Anyhow, this definately would be
a seperate patch. If you really want to, send a patch, and then I have
to think why we still need it ;)
> Ok. Perhaps I should also move the debug print with the registered
> adapter after calling i2c_init_recovery().
Yes, makes sense.
> Do you want me to integrate this patch in the previous one?
Nope, please keep it seperate.
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Re: Re: [RFC PATCH 3/4] i2c: core: treat EPROBE_DEFER when acquiring SCL/SDA GPIOs
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
>> ---
>> 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(>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, >dev,
>> + adap->dev.parent);
>> +#endif
>> out_reg:
>> init_completion(>dev_released);
>> device_unregister(>dev);
>> --
>> 2.25.1
>>
Do you want me to integrate this patch in the previous one?
Best regards,
Codrin
Re: [RFC PATCH 3/4] i2c: core: treat EPROBE_DEFER when acquiring SCL/SDA GPIOs
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
> ---
> 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.
> }
>
> 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(>dev, "Not using recovery: %s\n", err_str);
> adap->bus_recovery_info = NULL;
> +
> + return 0;
'return -EINVAL;' I'd suggest.
> }
>
> 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.
>
> /* 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, >dev,
> + adap->dev.parent);
> +#endif
> out_reg:
> init_completion(>dev_released);
> device_unregister(>dev);
> --
> 2.25.1
>
signature.asc
Description: PGP signature
[RFC PATCH 3/4] i2c: core: treat EPROBE_DEFER when acquiring SCL/SDA GPIOs
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
---
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;
}
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(>dev, "Not using recovery: %s\n", err_str);
adap->bus_recovery_info = NULL;
+
+ return 0;
}
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;
/* 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, >dev,
+adap->dev.parent);
+#endif
out_reg:
init_completion(>dev_released);
device_unregister(>dev);
--
2.25.1
