Re: [RFC PATCH] smsc911x: Ignore error return from device_get_phy_mode()

[Jeremy Linton <jeremy.linton@arm.com>]

On 08/26/2015 01:49 PM, Guenter Roeck wrote:
> Check the return value from device_property_read_u32() to see if there
> is a suitable firmware interface to read the data, and abort if not.
> The function should return -ENXIO in that case; however, it returns
> -ENODATA. Check for both.
>
> Fixes: 62ee783bf1f8 ("smsc911x: Fix crash seen if neither ACPI nor OF is configured or used")
> Signed-off-by: Guenter Roeck <linux@roeck-us.net>
> ---
> Needs testing. RFC because I am not sure if the -ENODATA check is acceptable.

I'm not really sure about it myself. I can think of cases where it might 
cause problems. That said it does work in an ACPI environment with or 
without the _DSD block. If the DSD/property isn't set, obviously the 
device doesn't configure (but it doesn't crash either) so that is good 
and an overall improvement for ACPI.

Also, I personally might have hoisted the reg-io-width ahead of the 
device_get_phy_mode() and removed the phy checks, but I don't imagine 
there is much functional difference at this point.

Tested-by: Jeremy Linton <jeremy.linton@arm.com>