于 2018年1月11日 GMT+08:00 下午7:48:40, Andre Przywara <andre.przywara@xxxxxxx> 写到:
>Hi,
>
>another take to avoid this patch at all, I just remembered this from an
>IRC discussion before:
>
>On 06/01/18 04:23, Icenowy Zheng wrote:
>> The Allwinner H6 pin controllers (both the main one and the CPUs one)
>> have no bus gate clocks.
>
>I don't think this is true. The pin controller *needs* an APB clock,
>it's just not gate-able or not exposed or documented.
>The "system bus tree" on page 90 in the manual shows that the "GPIO"
>block is located on the APB1 bus.
>So can't we just reference this apb clock directly? That would be much
>cleaner, "more" correct and require less changes: "The best patch is no
>patch":
I can accept this. (In fact I have considered this, but
I don't dare to directly use bus clock in a device, as it's not
exported before.
Maxime, Chen-Yu, can you agree the following code?
>
> clocks = <&ccu APB1>, <&osc24M>, <&osc32k>;
> /* or whatever this APB clock is actually called. */
> clock-names = "apb", "hosc", "losc";
>
>Cheers,
>Andre.
>
>>
>> Add support for this kind of pin controllers.
>>
>> Signed-off-by: Icenowy Zheng <icenowy@xxxxxxx>
>> ---
>> drivers/pinctrl/sunxi/pinctrl-sunxi.c | 30
>++++++++++++++++++++----------
>> drivers/pinctrl/sunxi/pinctrl-sunxi.h | 1 +
>> 2 files changed, 21 insertions(+), 10 deletions(-)
>>
>> diff --git a/drivers/pinctrl/sunxi/pinctrl-sunxi.c
>b/drivers/pinctrl/sunxi/pinctrl-sunxi.c
>> index 4b6cb25bc796..68cd505679d9 100644
>> --- a/drivers/pinctrl/sunxi/pinctrl-sunxi.c
>> +++ b/drivers/pinctrl/sunxi/pinctrl-sunxi.c
>> @@ -1182,7 +1182,12 @@ static int sunxi_pinctrl_setup_debounce(struct
>sunxi_pinctrl *pctl,
>> unsigned int hosc_div, losc_div;
>> struct clk *hosc, *losc;
>> u8 div, src;
>> - int i, ret;
>> + int i, ret, clk_count;
>> +
>> + if (pctl->desc->without_bus_gate)
>> + clk_count = 2;
>> + else
>> + clk_count = 3;
>>
>> /* Deal with old DTs that didn't have the oscillators */
>> if (of_count_phandle_with_args(node, "clocks", "#clock-cells") !=
>3)
>> @@ -1360,15 +1365,19 @@ int sunxi_pinctrl_init_with_variant(struct
>platform_device *pdev,
>> goto gpiochip_error;
>> }
>>
>> - clk = devm_clk_get(&pdev->dev, NULL);
>> - if (IS_ERR(clk)) {
>> - ret = PTR_ERR(clk);
>> - goto gpiochip_error;
>> - }
>> + if (!desc->without_bus_gate) {
>> + clk = devm_clk_get(&pdev->dev, NULL);
>> + if (IS_ERR(clk)) {
>> + ret = PTR_ERR(clk);
>> + goto gpiochip_error;
>> + }
>>
>> - ret = clk_prepare_enable(clk);
>> - if (ret)
>> - goto gpiochip_error;
>> + ret = clk_prepare_enable(clk);
>> + if (ret)
>> + goto gpiochip_error;
>> + } else {
>> + clk = NULL;
>> + }
>>
>> pctl->irq = devm_kcalloc(&pdev->dev,
>> pctl->desc->irq_banks,
>> @@ -1425,7 +1434,8 @@ int sunxi_pinctrl_init_with_variant(struct
>platform_device *pdev,
>> return 0;
>>
>> clk_error:
>> - clk_disable_unprepare(clk);
>> + if (clk)
>> + clk_disable_unprepare(clk);
>> gpiochip_error:
>> gpiochip_remove(pctl->chip);
>> return ret;
>> diff --git a/drivers/pinctrl/sunxi/pinctrl-sunxi.h
>b/drivers/pinctrl/sunxi/pinctrl-sunxi.h
>> index 11b128f54ed2..ccb6230f0bb5 100644
>> --- a/drivers/pinctrl/sunxi/pinctrl-sunxi.h
>> +++ b/drivers/pinctrl/sunxi/pinctrl-sunxi.h
>> @@ -113,6 +113,7 @@ struct sunxi_pinctrl_desc {
>> unsigned irq_bank_base;
>> bool irq_read_needs_mux;
>> bool disable_strict_mode;
>> + bool without_bus_gate;
>> };
>>
>> struct sunxi_pinctrl_function {
>>
>
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