[PATCH 1/3] clk: sunxi: improve mux_clk error handling and reporting

[Chen-Yu Tsai]

On Tue, Feb 16, 2016 at 5:45 PM, Andre Przywara <andre.przywara at arm.com> wrote:
> Hi Chen-Yu,
>
> On 13/02/16 02:44, Chen-Yu Tsai wrote:
>> Hi,
>>
>> On Fri, Feb 12, 2016 at 11:11 PM, Andre Przywara <andre.przywara at arm.com> wrote:
>>> We now catch and report a failing ioremap, also a failure in the final
>>> step of the clock registration is now handled and reported.
>>> Also warnings are turned into errors.
>>>
>>> Signed-off-by: Andre Przywara <andre.przywara at arm.com>
>>> ---
>>>  drivers/clk/sunxi/clk-sunxi.c | 19 +++++++++++++------
>>>  1 file changed, 13 insertions(+), 6 deletions(-)
>>>
>>> diff --git a/drivers/clk/sunxi/clk-sunxi.c b/drivers/clk/sunxi/clk-sunxi.c
>>> index 49ce283..361f396 100644
>>> --- a/drivers/clk/sunxi/clk-sunxi.c
>>> +++ b/drivers/clk/sunxi/clk-sunxi.c
>>> @@ -690,11 +690,15 @@ static struct clk * __init sunxi_mux_clk_setup(struct device_node *node,
>>>         int i;
>>>
>>>         reg = of_iomap(node, 0);
>>> +       if (!reg) {
>>> +               pr_err("Could not map registers for mux-clk: %s\n", node->name);
>>
>> of_node_full_name(node->name) is better. node->name is almost always "clk",
>> which is useless. (Unless someone goes through the dts files to replace all
>> of them.)
>
> Good point. I both fixed the code here as well as amended the node names
> in the A64 DT.
>
>>
>>> +               return NULL;
>>> +       }
>>>
>>>         i = of_clk_parent_fill(node, parents, SUNXI_MAX_PARENTS);
>>>         if (of_property_read_string(node, "clock-output-names", &clk_name)) {
>>> -               pr_warn("%s: could not read clock-output-names for \"%s\"\n",
>>> -                       __func__, clk_name);
>>> +               pr_err("%s: could not read clock-output-names for \"%s\"\n",
>>> +                      __func__, clk_name);
>>
>> Same here. clk_name defaults to node->name. If you could, please replace it.
>
> Really? Isn't clk_name directly from the DT clock-output-names strings here?

It fills it from the DT clock-output-names in the of_property_read_string()
call in the if here. If that failed, obviously something was wrong with
the DT clock-output-names strings. :)

>
>>>                 goto out_unmap;
>>>         }
>>>
>>> @@ -704,14 +708,17 @@ static struct clk * __init sunxi_mux_clk_setup(struct device_node *node,
>>>                                0, &clk_lock);
>>>
>>>         if (IS_ERR(clk)) {
>>> -               pr_warn("%s: failed to register mux clock %s: %ld\n", __func__,
>>> -                       clk_name, PTR_ERR(clk));
>>> +               pr_err("%s: failed to register mux clock %s: %ld\n", __func__,
>>> +                      clk_name, PTR_ERR(clk));
>>>                 goto out_unmap;
>>>         }
>>>
>>> -       of_clk_add_provider(node, of_clk_src_simple_get, clk);
>>> +       if (!of_clk_add_provider(node, of_clk_src_simple_get, clk))
>>> +               return clk;
>>> +
>>> +       pr_err("%s: failed to add clock provider for %s\n", __func__, clk_name);
>>>
>>> -       return clk;
>>
>> I'd have all the error path in ifs, and have the normal return path
>> here for consistency.
>> But I guess this works as well.
>
> Yeah, I wanted to skip that single goto ;-)
> But I changed it now as you said and it indeed looks more reasonable.
>
> I took the freedom of applying the comments to the other patches too.

Thanks!
ChenYu

>
> Will send out a v2 in a minute.
>
> Thanks for looking!
> Andre.
>
>>
>> Thanks!
>> ChenYu
>>
>>> +       clk_unregister_divider(clk);
>>>
>>>  out_unmap:
>>>         iounmap(reg);
>>> --
>>> 2.6.4
>>>
>>