Re: [PATCH RFC 4/5] drm/msm/hdmi: deprecate non standard clock-names

[Srinivas Kandagatla <srinivas.kandagatla@linaro.org>]

On 10/08/15 14:33, Thierry Reding wrote:
> On Mon, Aug 10, 2015 at 02:18:15PM +0100, Srinivas Kandagatla wrote:
>>
>>
>> On 10/08/15 13:49, Thierry Reding wrote:
>>> On Mon, Aug 10, 2015 at 12:59:49PM +0100, Srinivas Kandagatla wrote:
>>>> This patch updates the bindings to discourage the usage of non standard
>>>> clock names, this will help in projects focused on upstreaming.
>>>>
>>>> These deprecated properties are still supported but will be remove over
>>>> the time.
>>>>
>>>> Signed-off-by: Srinivas Kandagatla <srinivas.kandagatla@linaro.org>
>>>> ---
>>>>   Documentation/devicetree/bindings/drm/msm/hdmi.txt | 16 ++++++++--------
>>>>   1 file changed, 8 insertions(+), 8 deletions(-)
>>>>
>>>> diff --git a/Documentation/devicetree/bindings/drm/msm/hdmi.txt b/Documentation/devicetree/bindings/drm/msm/hdmi.txt
>>>> index 6dc202e..6fbfdd8 100644
>>>> --- a/Documentation/devicetree/bindings/drm/msm/hdmi.txt
>>>> +++ b/Documentation/devicetree/bindings/drm/msm/hdmi.txt
>>>> @@ -12,16 +12,16 @@ Required properties:
>>>>   - clocks: device clocks
>>>>   - clock-names: Corresponding name for each entry in the clocks property.
>>>>    for "qcom,hdmi-tx-8960" compatible names should be
>>>> -	"core_clk"
>>>> -	"master_iface_clk"
>>>> -	"slave_iface_clk"
>>>> +	"core_clk" is deprecated, use "core" instead
>>>> +	"master_iface_clk" is deprecated, use "master_iface" instead
>>>> +	"slave_iface_clk" is deprecated, use "slave_iface" instead
>>>>
>>>>    for "qcom,hdmi-tx-8084" and "qcom,hdmi-tx-8074" compatible names should be
>>>> -	"extp_clk"
>>>> -	"alt_iface_clk"
>>>> -	"iface_clk"
>>>> -	"core_clk"
>>>> -	"mdp_core_clk"
>>>> +	"extp_clk" is deprecated, use "extp" instead
>>>> +	"alt_iface_clk" is deprecated, use "alt_iface" intstead
>>>> +	"iface_clk" is deprecated, use "iface" instead
>>>> +	"core_clk" is deprecated, use "core" instead
>>>> +	"mdp_core_clk" is deprecated, use "mdp_core" instead
>>>
>>> Shouldn't there be a driver counterpart of this to accept the new names?
>> Driver changes are in this same series "[PATCH RFC 5/5] drm/msm/hdmi: remove
>> _clk suffix from clock names"(https://lkml.org/lkml/2015/8/10/453)
>
> I don't have that patch in my inbox. It looks to be doing things
> backwards (look up the deprecated name first). I think it should be:
>
> 	clk = devm_clk_get(dev, id);
> 	if (IS_ERR(clk)) {
If the clock controller is not ready yet, it would return EPROBE DEFER, 
which gets dropped here, as a result the driver would not be probed again.

Probably both of the error codes needs be checked before returning.
> 		char clk_name[32];
>
> 		snprintf(clk_name, sizeof(clk_name), "%s_clk", id);
> 		clk = devm_clk_get(dev, clk_name);
> 		if (IS_ERR(clk))
> 			return clk;
> 	}
>
> Also note how I've dropped the ERR_CAST(), that's not useful here
> because you aren't actually casting, but simply returning clk.
>
> Thierry
>