[PATCH v4 3/3] mmc: mediatek: add support for SDIO eint IRQ

[Axe Yang]

On Wed, 2022-01-19 at 21:47 +0200, Andy Shevchenko wrote:
> On Wed, Jan 19, 2022 at 06:32:12PM +0800, Axe Yang wrote:
> > Add support for eint IRQ when MSDC is used as an SDIO host. This
> > feature requires SDIO device support async IRQ function. With this
> > feature, SDIO host can be awakened by SDIO card in suspend state,
> > without additional pin.
> > 
> > MSDC driver will time-share the SDIO DAT1 pin. During suspend, MSDC
> > turn off clock and switch SDIO DAT1 pin to GPIO mode. And during
> > resume, switch GPIO function back to DAT1 mode then turn on clock.
> > 
> > Some device tree property should be added or modified in MSDC node
> > to support SDIO eint IRQ. Pinctrls named state_dat1 and state_eint
> > are mandatory. And cap-sdio-async-irq flag is necessary since this
> > feature depends on asynchronous interrupt:
> >         &mmcX {
> >                 ...
> >                 pinctrl-names = "default", "state_uhs",
> > "state_eint",
> >                                 "state_dat1";
> >                 ...
> >                 pinctrl-2 = <&mmc2_pins_eint>;
> >                 pinctrl-3 = <&mmc2_pins_dat1>;
> >                 ...
> >                 cap-sdio-async-irq;
> >                 ...
> >         };
> > 
> > Signed-off-by: Axe Yang <axe.yang at mediatek.com>
> 
> The submitters SoB must be last among all SoB tags. Please, read
> Submitting
> Patches document carefully.
> 
> > Signed-off-by: Yong Mao <yong.mao at mediatek.com>
> 
> Who is they, why their SoB appeared here?
> 

Yong Mao is the co-developer of this patch, I will reorder the SoB
chains.

> ...
> 
> >  /*
> > - * Copyright (c) 2014-2015 MediaTek Inc.
> > + * Copyright (c) 2022 MediaTek Inc.
> 
> This doesn't feel right. Why did you remove old years?

I should keep the publish year 2014 of this driver.
But I still think range 2014-2022 is the most appropriate way to change
the copyright time. Over these years, mediatek is keeping maintaining
this driver continuously. What do you think?

> 
> >   * Author: Chaotian.Jing <chaotian.jing at mediatek.com>
> >   */
> 
> ...
> 
> > +	desc = devm_gpiod_get(host->dev, "eint", GPIOD_IN);
> > +	if (IS_ERR(desc))
> > +		return PTR_ERR(desc);
> > +	ret = gpiod_to_irq(desc);
> > +	if (ret < 0)
> > +		return ret;
> > +
> > +	irq = ret;
> 
> Since both of them are local variables and there is no specific use
> of the
> returned value, I believe it's fine just to
> 
> 	irq = gpiod_to_irq(desc);
> 	...

I agree, will fix in next version.

> Hmm... I was wondering if you can use fwnode_irq_get_byname().
> Ah, it's not (yet) in upstream.
> 
> ...
> 
> >  static int __maybe_unused msdc_runtime_suspend(struct device *dev)
> >  {
> > +	unsigned long flags;
> 
> Can you keep reversed xmas tree order?
> 
> >  	struct mmc_host *mmc = dev_get_drvdata(dev);
> >  	struct msdc_host *host = mmc_priv(mmc);
> 
> (it means to add new variable here)

Will fix it in next version.

> 
> >  	return 0;
> >  }
> 
> ...
> 
> >  static int __maybe_unused msdc_runtime_resume(struct device *dev)
> >  {
> > +	unsigned long flags;
> 
> Ditto.

Will fix it in next version.

> 
> >  	struct mmc_host *mmc = dev_get_drvdata(dev);
> >  	struct msdc_host *host = mmc_priv(mmc);
> >  	int ret;
> >  	return 0;
> >  }
> 

--
Best Regard,
Axe Yang