Messages in this thread | | | Subject | Re: [PATCH v1 1/2] pinctrl: pinctrl-loongson2: add pinctrl driver support | From | Yinbo Zhu <> | Date | Sat, 22 Oct 2022 09:55:08 +0800 |
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在 2022/10/21 下午5:45, Linus Walleij 写道: > Hi Yinbo, > > thanks for your patch! > > On Fri, Oct 21, 2022 at 3:27 AM Yinbo Zhu <zhuyinbo@loongson.cn> wrote: > >> The loongson2 SoC has a few pins that can be used as GPIOs or take >> multiple other functions. Add a driver for the pinmuxing. >> >> There is currently no support for GPIO pin pull-up and pull-down. >> >> Signed-off-by: zhanghongchen <zhanghongchen@loongson.cn> >> Signed-off-by: Yinbo Zhu <zhuyinbo@loongson.cn> > > (...) > >> +static int loongson2_pmx_set_mux(struct pinctrl_dev *pcdev, unsigned int func_num, >> + unsigned int group_num) >> +{ >> + struct loongson2_pinctrl *pctrl = pinctrl_dev_get_drvdata(pcdev); >> + unsigned long reg = (unsigned long)pctrl->reg_base + >> + loongson2_pmx_groups[group_num].reg; >> + unsigned int mux_bit = loongson2_pmx_groups[group_num].bit; >> + unsigned int val; >> + unsigned long flags; >> + >> + raw_spin_lock_irqsave(&pctrl->lock, flags); >> + val = readl((void *)reg); >> + if (func_num == 0) >> + val &= ~(1<<mux_bit); >> + else >> + val |= (1<<mux_bit); >> + writel(val, (void *)reg); >> + raw_spin_unlock_irqrestore(&pctrl->lock, flags); > > Can you explain in the commit message or with a comment in the code > why you have to use a raw spinlock for this? > > We usually only use raw spinlocks for things like low level > interrupt handlers... > > My guess is that you can replace this with an ordinary spinlock. I was refer other platform, eg. pinctrl-amd.c, if the ordinary spinlock was more appropriate I will use the ordinary spinlock.
TKs Yinbo. > > Yours, > Linus Walleij >
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