Re: [PATCH v3 03/22] usb: ulpi: Support device discovery via device properties

[Stephen Boyd]

On Fri, Sep 2, 2016 at 7:09 AM, Heikki Krogerus
 wrote:
> Hi,
>
> On Wed, Aug 31, 2016 at 05:40:17PM -0700, Stephen Boyd wrote:
>> @@ -174,14 +219,37 @@ static int ulpi_register(struct device *dev, struct 
>> ulpi *ulpi)
>>   ulpi->id.product = ulpi_read(ulpi, ULPI_PRODUCT_ID_LOW);
>>   ulpi->id.product |= ulpi_read(ulpi, ULPI_PRODUCT_ID_HIGH) << 8;
>>
>> + return 0;
>> +}
>> +
>> +static int ulpi_register(struct device *dev, struct ulpi *ulpi)
>> +{
>> + int ret;
>> +
>>   ulpi->dev.parent = dev;
>>   ulpi->dev.bus = _bus;
>>   ulpi->dev.type = _dev_type;
>>   dev_set_name(>dev, "%s.ulpi", dev_name(dev));
>>
>> + if (IS_ENABLED(CONFIG_OF)) {
>
> I don't think you need to check that in this case.
>
>> + ret = ulpi_of_register(ulpi);
>> + if (ret)
>> + return ret;
>> + }
>> +
>>   ACPI_COMPANION_SET(>dev, ACPI_COMPANION(dev));
>
> ACPI_COMPANION_SET will overwrite the primary fwnode unconditionally,
> so just to play it safe, do this before you call ulpi_of_register().

Ok.

>
>> - request_module("ulpi:v%04xp%04x", ulpi->id.vendor, ulpi->id.product);
>> + ret = ulpi_read_id(ulpi);
>> + /*
>> +  * Ignore failure in case of DT node because the device may
>> +  * not be powered up yet but we can still match by compatible
>> +  */
>> + if (ret && !ulpi->dev.of_node)
>> + return ret;
>> +
>> + if (of_device_request_module(>dev))
>> + request_module("ulpi:v%04xp%04x", ulpi->id.vendor,
>> +ulpi->id.product);
>
> I don't think this works in all cases. If of_device_request_module()
> fails and we don't have the id.vendor/product set, we should not
> register the device. It also looks a bit messy.
>
> How about just using of_device_request_module() call as fallback in
> ulpi_read_id() and moving also request_module() call there:

Sure I'll fold it in and test. Should we "goto err" if we can't read
the scratch register though? I would think that's a "real" failure and
we shouldn't try to support DT in that case.

Re: [PATCH v3 03/22] usb: ulpi: Support device discovery via device properties

[Stephen Boyd]

On Fri, Sep 2, 2016 at 7:09 AM, Heikki Krogerus
 wrote:
> Hi,
>
> On Wed, Aug 31, 2016 at 05:40:17PM -0700, Stephen Boyd wrote:
>> @@ -174,14 +219,37 @@ static int ulpi_register(struct device *dev, struct 
>> ulpi *ulpi)
>>   ulpi->id.product = ulpi_read(ulpi, ULPI_PRODUCT_ID_LOW);
>>   ulpi->id.product |= ulpi_read(ulpi, ULPI_PRODUCT_ID_HIGH) << 8;
>>
>> + return 0;
>> +}
>> +
>> +static int ulpi_register(struct device *dev, struct ulpi *ulpi)
>> +{
>> + int ret;
>> +
>>   ulpi->dev.parent = dev;
>>   ulpi->dev.bus = _bus;
>>   ulpi->dev.type = _dev_type;
>>   dev_set_name(>dev, "%s.ulpi", dev_name(dev));
>>
>> + if (IS_ENABLED(CONFIG_OF)) {
>
> I don't think you need to check that in this case.
>
>> + ret = ulpi_of_register(ulpi);
>> + if (ret)
>> + return ret;
>> + }
>> +
>>   ACPI_COMPANION_SET(>dev, ACPI_COMPANION(dev));
>
> ACPI_COMPANION_SET will overwrite the primary fwnode unconditionally,
> so just to play it safe, do this before you call ulpi_of_register().

Ok.

>
>> - request_module("ulpi:v%04xp%04x", ulpi->id.vendor, ulpi->id.product);
>> + ret = ulpi_read_id(ulpi);
>> + /*
>> +  * Ignore failure in case of DT node because the device may
>> +  * not be powered up yet but we can still match by compatible
>> +  */
>> + if (ret && !ulpi->dev.of_node)
>> + return ret;
>> +
>> + if (of_device_request_module(>dev))
>> + request_module("ulpi:v%04xp%04x", ulpi->id.vendor,
>> +ulpi->id.product);
>
> I don't think this works in all cases. If of_device_request_module()
> fails and we don't have the id.vendor/product set, we should not
> register the device. It also looks a bit messy.
>
> How about just using of_device_request_module() call as fallback in
> ulpi_read_id() and moving also request_module() call there:

Sure I'll fold it in and test. Should we "goto err" if we can't read
the scratch register though? I would think that's a "real" failure and
we shouldn't try to support DT in that case.

Re: [PATCH v3 03/22] usb: ulpi: Support device discovery via device properties

[Heikki Krogerus]

Hi,

On Wed, Aug 31, 2016 at 05:40:17PM -0700, Stephen Boyd wrote:
> @@ -174,14 +219,37 @@ static int ulpi_register(struct device *dev, struct 
> ulpi *ulpi)
>   ulpi->id.product = ulpi_read(ulpi, ULPI_PRODUCT_ID_LOW);
>   ulpi->id.product |= ulpi_read(ulpi, ULPI_PRODUCT_ID_HIGH) << 8;
>  
> + return 0;
> +}
> +
> +static int ulpi_register(struct device *dev, struct ulpi *ulpi)
> +{
> + int ret;
> +
>   ulpi->dev.parent = dev;
>   ulpi->dev.bus = _bus;
>   ulpi->dev.type = _dev_type;
>   dev_set_name(>dev, "%s.ulpi", dev_name(dev));
>  
> + if (IS_ENABLED(CONFIG_OF)) {

I don't think you need to check that in this case.

> + ret = ulpi_of_register(ulpi);
> + if (ret)
> + return ret;
> + }
> +
>   ACPI_COMPANION_SET(>dev, ACPI_COMPANION(dev));

ACPI_COMPANION_SET will overwrite the primary fwnode unconditionally,
so just to play it safe, do this before you call ulpi_of_register().

> - request_module("ulpi:v%04xp%04x", ulpi->id.vendor, ulpi->id.product);
> + ret = ulpi_read_id(ulpi);
> + /*
> +  * Ignore failure in case of DT node because the device may
> +  * not be powered up yet but we can still match by compatible
> +  */
> + if (ret && !ulpi->dev.of_node)
> + return ret;
> +
> + if (of_device_request_module(>dev))
> + request_module("ulpi:v%04xp%04x", ulpi->id.vendor,
> +ulpi->id.product);

I don't think this works in all cases. If of_device_request_module()
fails and we don't have the id.vendor/product set, we should not
register the device. It also looks a bit messy.

How about just using of_device_request_module() call as fallback in
ulpi_read_id() and moving also request_module() call there:

diff --git a/drivers/usb/common/ulpi.c b/drivers/usb/common/ulpi.c
index 30ea770..667246c 100644
--- a/drivers/usb/common/ulpi.c
+++ b/drivers/usb/common/ulpi.c
@@ -205,14 +205,14 @@ static int ulpi_read_id(struct ulpi *ulpi)
/* Test the interface */
ret = ulpi_write(ulpi, ULPI_SCRATCH, 0xaa);
if (ret < 0)
-   return ret;
+   goto err;
 
ret = ulpi_read(ulpi, ULPI_SCRATCH);
if (ret < 0)
-   return ret;
+   goto err;
 
if (ret != 0xaa)
-   return -ENODEV;
+   goto err;
 
ulpi->id.vendor = ulpi_read(ulpi, ULPI_VENDOR_ID_LOW);
ulpi->id.vendor |= ulpi_read(ulpi, ULPI_VENDOR_ID_HIGH) << 8;
@@ -220,7 +220,11 @@ static int ulpi_read_id(struct ulpi *ulpi)
ulpi->id.product = ulpi_read(ulpi, ULPI_PRODUCT_ID_LOW);
ulpi->id.product |= ulpi_read(ulpi, ULPI_PRODUCT_ID_HIGH) << 8;
 
+   request_module("ulpi:v%04xp%04x", ulpi->id.vendor, ulpi->id.product);
+
return 0;
+err:
+   return of_device_request_module(>dev);
 }
 
 static int ulpi_register(struct device *dev, struct ulpi *ulpi)
@@ -232,25 +236,15 @@ static int ulpi_register(struct device *dev, struct ulpi 
*ulpi)
ulpi->dev.type = _dev_type;
dev_set_name(>dev, "%s.ulpi", dev_name(dev));
 
-   if (IS_ENABLED(CONFIG_OF)) {
-   ret = ulpi_of_register(ulpi);
-   if (ret)
-   return ret;
-   }
-
ACPI_COMPANION_SET(>dev, ACPI_COMPANION(dev));
 
-   ret = ulpi_read_id(ulpi);
-   /*
-* Ignore failure in case of DT node because the device may
-* not be powered up yet but we can still match by compatible
-*/
-   if (ret && !ulpi->dev.of_node)
+   ret = ulpi_of_register(ulpi);
+   if (ret)
return ret;
 
-   if (of_device_request_module(>dev))
-   request_module("ulpi:v%04xp%04x", ulpi->id.vendor,
-  ulpi->id.product);
+   ret = ulpi_read_id(ulpi);
+   if (ret)
+   return ret;
 
ret = device_register(>dev);
if (ret)


Cheers,

-- 
heikki

Re: [PATCH v3 03/22] usb: ulpi: Support device discovery via device properties

[Heikki Krogerus]

Hi,

On Wed, Aug 31, 2016 at 05:40:17PM -0700, Stephen Boyd wrote:
> @@ -174,14 +219,37 @@ static int ulpi_register(struct device *dev, struct 
> ulpi *ulpi)
>   ulpi->id.product = ulpi_read(ulpi, ULPI_PRODUCT_ID_LOW);
>   ulpi->id.product |= ulpi_read(ulpi, ULPI_PRODUCT_ID_HIGH) << 8;
>  
> + return 0;
> +}
> +
> +static int ulpi_register(struct device *dev, struct ulpi *ulpi)
> +{
> + int ret;
> +
>   ulpi->dev.parent = dev;
>   ulpi->dev.bus = _bus;
>   ulpi->dev.type = _dev_type;
>   dev_set_name(>dev, "%s.ulpi", dev_name(dev));
>  
> + if (IS_ENABLED(CONFIG_OF)) {

I don't think you need to check that in this case.

> + ret = ulpi_of_register(ulpi);
> + if (ret)
> + return ret;
> + }
> +
>   ACPI_COMPANION_SET(>dev, ACPI_COMPANION(dev));

ACPI_COMPANION_SET will overwrite the primary fwnode unconditionally,
so just to play it safe, do this before you call ulpi_of_register().

> - request_module("ulpi:v%04xp%04x", ulpi->id.vendor, ulpi->id.product);
> + ret = ulpi_read_id(ulpi);
> + /*
> +  * Ignore failure in case of DT node because the device may
> +  * not be powered up yet but we can still match by compatible
> +  */
> + if (ret && !ulpi->dev.of_node)
> + return ret;
> +
> + if (of_device_request_module(>dev))
> + request_module("ulpi:v%04xp%04x", ulpi->id.vendor,
> +ulpi->id.product);

I don't think this works in all cases. If of_device_request_module()
fails and we don't have the id.vendor/product set, we should not
register the device. It also looks a bit messy.

How about just using of_device_request_module() call as fallback in
ulpi_read_id() and moving also request_module() call there:

diff --git a/drivers/usb/common/ulpi.c b/drivers/usb/common/ulpi.c
index 30ea770..667246c 100644
--- a/drivers/usb/common/ulpi.c
+++ b/drivers/usb/common/ulpi.c
@@ -205,14 +205,14 @@ static int ulpi_read_id(struct ulpi *ulpi)
/* Test the interface */
ret = ulpi_write(ulpi, ULPI_SCRATCH, 0xaa);
if (ret < 0)
-   return ret;
+   goto err;
 
ret = ulpi_read(ulpi, ULPI_SCRATCH);
if (ret < 0)
-   return ret;
+   goto err;
 
if (ret != 0xaa)
-   return -ENODEV;
+   goto err;
 
ulpi->id.vendor = ulpi_read(ulpi, ULPI_VENDOR_ID_LOW);
ulpi->id.vendor |= ulpi_read(ulpi, ULPI_VENDOR_ID_HIGH) << 8;
@@ -220,7 +220,11 @@ static int ulpi_read_id(struct ulpi *ulpi)
ulpi->id.product = ulpi_read(ulpi, ULPI_PRODUCT_ID_LOW);
ulpi->id.product |= ulpi_read(ulpi, ULPI_PRODUCT_ID_HIGH) << 8;
 
+   request_module("ulpi:v%04xp%04x", ulpi->id.vendor, ulpi->id.product);
+
return 0;
+err:
+   return of_device_request_module(>dev);
 }
 
 static int ulpi_register(struct device *dev, struct ulpi *ulpi)
@@ -232,25 +236,15 @@ static int ulpi_register(struct device *dev, struct ulpi 
*ulpi)
ulpi->dev.type = _dev_type;
dev_set_name(>dev, "%s.ulpi", dev_name(dev));
 
-   if (IS_ENABLED(CONFIG_OF)) {
-   ret = ulpi_of_register(ulpi);
-   if (ret)
-   return ret;
-   }
-
ACPI_COMPANION_SET(>dev, ACPI_COMPANION(dev));
 
-   ret = ulpi_read_id(ulpi);
-   /*
-* Ignore failure in case of DT node because the device may
-* not be powered up yet but we can still match by compatible
-*/
-   if (ret && !ulpi->dev.of_node)
+   ret = ulpi_of_register(ulpi);
+   if (ret)
return ret;
 
-   if (of_device_request_module(>dev))
-   request_module("ulpi:v%04xp%04x", ulpi->id.vendor,
-  ulpi->id.product);
+   ret = ulpi_read_id(ulpi);
+   if (ret)
+   return ret;
 
ret = device_register(>dev);
if (ret)


Cheers,

-- 
heikki