Re: [PATCH 2/2] USB: ehci-omap: Improve PHY error handling

[Roger Quadros <rogerq@ti.com>]

On 04/16/2013 06:32 PM, Alan Stern wrote:
> On Mon, 15 Apr 2013, Roger Quadros wrote:
> 
>> As the USB PHY layer never returns NULL we don't need
>> to check for that condition.
>>
>> If we fail to get the PHY device it could be due
>> to missing USB PHY drivers. Give this hint to the user
>> in the error message.
>>
>> CC: Alan Stern <stern@rowland.harvard.edu>
>> Signed-off-by: Roger Quadros <rogerq@ti.com>
>> ---
>>  drivers/usb/host/ehci-omap.c |    6 +++---
>>  1 files changed, 3 insertions(+), 3 deletions(-)
>>
>> diff --git a/drivers/usb/host/ehci-omap.c b/drivers/usb/host/ehci-omap.c
>> index 5de3e43..2e34ddd 100644
>> --- a/drivers/usb/host/ehci-omap.c
>> +++ b/drivers/usb/host/ehci-omap.c
>> @@ -175,13 +175,13 @@ static int ehci_hcd_omap_probe(struct platform_device *pdev)
>>  			phy = devm_usb_get_phy_by_phandle(dev, "phys", i);
>>  		else
>>  			phy = devm_usb_get_phy_dev(dev, i);
>> -		if (IS_ERR(phy) || !phy) {
>> +		if (IS_ERR(phy)) {
>>  			/* Don't bail out if PHY is not absolutely necessary */
>>  			if (pdata->port_mode[i] != OMAP_EHCI_PORT_MODE_PHY)
>>  				continue;
>>  
>> -			ret = IS_ERR(phy) ? PTR_ERR(phy) : -ENODEV;
>> -			dev_err(dev, "Can't get PHY device for port %d: %d\n",
>> +			ret = PTR_ERR(phy);
>> +			dev_err(dev, "Can't get PHY device for port %d: %d. Is USB_PHY driver enabled?\n",
>>  					i, ret);
>>  			goto err_phy;
>>  		}
> 
> Getting rid of the !phy test is good.  But I'm doubtful about the 
> change to the error message.  Are you going to make a similar change to 
> every platform driver?  There doesn't seem to be any reason to do this 
> for ehci-omap but not the others.

I'm not very sure about that. If using the PHY API while USB_PHY is disabled
is to be treated as a universal failure, then the print might as well come from
the dummy stub for xx_usb_get_phy_xx().

For this patch, I'll just undo the print message change and resend. That could be
done in a separate patch instead.

cheers,
-roger