[PATCH v2 08/12] pinctrl: qcom: use generic pin function helpers
Konrad Dybcio
konrad.dybcio at oss.qualcomm.com
Fri Jul 11 05:19:26 PDT 2025
On 7/10/25 3:38 PM, Bartosz Golaszewski wrote:
> On Thu, Jul 10, 2025 at 2:25 PM Konrad Dybcio
> <konrad.dybcio at oss.qualcomm.com> wrote:
>>
>> On 7/9/25 4:39 PM, Bartosz Golaszewski wrote:
>>> From: Bartosz Golaszewski <bartosz.golaszewski at linaro.org>
>>>
>>> Use the existing infrastructure for storing and looking up pin functions
>>> in pinctrl core. Remove hand-crafted callbacks.
>>>
>>> Signed-off-by: Bartosz Golaszewski <bartosz.golaszewski at linaro.org>
>>> ---
>>
>> [...]
>>
>>> int msm_pinctrl_probe(struct platform_device *pdev,
>>> const struct msm_pinctrl_soc_data *soc_data)
>>> {
>>> + const struct pinfunction *func;
>>> struct msm_pinctrl *pctrl;
>>> struct resource *res;
>>> int ret;
>>> @@ -1606,6 +1581,14 @@ int msm_pinctrl_probe(struct platform_device *pdev,
>>> return PTR_ERR(pctrl->pctrl);
>>> }
>>>
>>> + for (i = 0; i < soc_data->nfunctions; i++) {
>>> + func = &soc_data->functions[i];
>>> +
>>> + ret = pinmux_generic_add_pinfunction(pctrl->pctrl, func, NULL);
>>> + if (ret < 0)
>>> + return ret;
>>> + }
>>
>> It's good in principle, but we're now going to house two copies of
>> the function data in memory... Can we trust __initconst nowadays?
>>
>
> Well, if I annotate the functions struct with __initconst, then it
> does indeed end up in the .init.rodata section if that's your
> question. Then the kernel seems to be freeing this in
> ./kernel/module/main.c so I sure hope we can trust it.
>
> Do I understand correctly that you're implicitly asking to also
> annotate all affected _functions structures across all tlmm drivers?
>
> Alternatively: we can provide another interface:
> pinmux_generic_add_const_pinfunction() which - instead of a deep-copy
> - would simply store addresses of existing pinfunction structures in
> the underlying radix tree.
This option seems like less of a churn
Konrad
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