Re: [PATCH v3 6/6] pwm: mediatek: add MT2712/MT7622 support

[Zhi Mao]

Hi Thierry,

Thanks for your review  code.
I will modify the code as you comment in the next release.

Regards
Zhi

On Mon, 2017-08-21 at 10:05 +0200, Thierry Reding wrote:
> On Fri, Jun 30, 2017 at 02:05:21PM +0800, Zhi Mao wrote:
> > 1. support multiple chip(MT2712, MT7622, MT7623)
> > 2. add mtk_pwm_com_reg for match the registers of MT2712 pwm8
> >    the register offset address of pwm8 for MT2712 is not fixed 0x40
> >    and they are not the same as pwm0~6.
> > 
> > Signed-off-by: Zhi Mao <zhi.mao@xxxxxxxxxxxx>
> > ---
> >  drivers/pwm/pwm-mediatek.c |   55 +++++++++++++++++++++++++++++++++++---------
> >  1 file changed, 44 insertions(+), 11 deletions(-)
> > 
> > diff --git a/drivers/pwm/pwm-mediatek.c b/drivers/pwm/pwm-mediatek.c
> > index 1d78ab1..2c9ce24 100644
> > --- a/drivers/pwm/pwm-mediatek.c
> > +++ b/drivers/pwm/pwm-mediatek.c
> > @@ -16,6 +16,7 @@
> >  #include <linux/module.h>
> >  #include <linux/clk.h>
> >  #include <linux/of.h>
> > +#include <linux/of_device.h>
> >  #include <linux/platform_device.h>
> >  #include <linux/pwm.h>
> >  #include <linux/slab.h>
> > @@ -40,11 +41,19 @@ enum {
> >  	MTK_CLK_PWM3,
> >  	MTK_CLK_PWM4,
> >  	MTK_CLK_PWM5,
> > +	MTK_CLK_PWM6,
> > +	MTK_CLK_PWM7,
> > +	MTK_CLK_PWM8,
> >  	MTK_CLK_MAX,
> >  };
> >  
> > -static const char * const mtk_pwm_clk_name[] = {
> > -	"main", "top", "pwm1", "pwm2", "pwm3", "pwm4", "pwm5"
> > +static const char * const mtk_pwm_clk_name[MTK_CLK_MAX] = {
> > +	"main", "top", "pwm1", "pwm2", "pwm3", "pwm4",
> > +	"pwm5", "pwm6", "pwm7", "pwm8"
> 
> You're wrapping these lines at arbitrary boundaries. Make sure to use
> all of the 80 columns at your disposal.
> 
> > +};
> > +
> > +struct mtk_com_pwm_data {
> 
> What does the _com stand for in the above?
> 
> > +	unsigned int pwm_nums;
> >  };
> 
> Maybe name this num_pwms for consistency with other drivers?
> 
> >  
> >  /**
> > @@ -57,6 +66,11 @@ struct mtk_pwm_chip {
> >  	struct pwm_chip chip;
> >  	void __iomem *regs;
> >  	struct clk *clks[MTK_CLK_MAX];
> > +	const struct mtk_com_pwm_data *data;
> > +};
> > +
> > +static const unsigned long mtk_pwm_com_reg[] = {
> 
> There's another of these _com that I don't understand what it means.
> Also since these are all fairly small offsets, these can simply be
> unsigned int.
> 
> > +	0x0010, 0x0050, 0x0090, 0x00d0, 0x0110, 0x0150, 0x0190, 0x0220
> >  };
> >  
> >  static inline struct mtk_pwm_chip *to_mtk_pwm_chip(struct pwm_chip *chip)
> > @@ -103,14 +117,14 @@ static void mtk_pwm_clk_disable(struct pwm_chip *chip, struct pwm_device *pwm)
> >  static inline u32 mtk_pwm_readl(struct mtk_pwm_chip *chip, unsigned int num,
> >  				unsigned int offset)
> >  {
> > -	return readl(chip->regs + 0x10 + (num * 0x40) + offset);
> > +	return readl(chip->regs + mtk_pwm_com_reg[num] + offset);
> >  }
> >  
> >  static inline void mtk_pwm_writel(struct mtk_pwm_chip *chip,
> >  				  unsigned int num, unsigned int offset,
> >  				  u32 value)
> >  {
> > -	writel(value, chip->regs + 0x10 + (num * 0x40) + offset);
> > +	writel(value, chip->regs + mtk_pwm_com_reg[num] + offset);
> >  }
> >  
> >  static int mtk_pwm_config(struct pwm_chip *chip, struct pwm_device *pwm,
> > @@ -194,23 +208,28 @@ static int mtk_pwm_probe(struct platform_device *pdev)
> >  	if (!pc)
> >  		return -ENOMEM;
> >  
> > +	pc->data = of_device_get_match_data(&pdev->dev);
> > +
> >  	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
> >  	pc->regs = devm_ioremap_resource(&pdev->dev, res);
> >  	if (IS_ERR(pc->regs))
> >  		return PTR_ERR(pc->regs);
> >  
> > -	for (i = 0; i < MTK_CLK_MAX; i++) {
> > +	for (i = 0; i < pc->data->pwm_nums + 2; i++) {
> >  		pc->clks[i] = devm_clk_get(&pdev->dev, mtk_pwm_clk_name[i]);
> > -		if (IS_ERR(pc->clks[i]))
> > +		if (IS_ERR(pc->clks[i])) {
> > +			dev_err(&pdev->dev, "[PWM] clock: %s fail: %ld\n",
> > +				mtk_pwm_clk_name[i], PTR_ERR(pc->clks[i]));
> 
> Why include the "[PWM] " prefix in the above message?
> 
> >  			return PTR_ERR(pc->clks[i]);
> > +		}
> >  	}
> >  
> > -	platform_set_drvdata(pdev, pc);
> > -
> >  	pc->chip.dev = &pdev->dev;
> >  	pc->chip.ops = &mtk_pwm_ops;
> >  	pc->chip.base = -1;
> > -	pc->chip.npwm = 5;
> > +	pc->chip.npwm = pc->data->pwm_nums;
> > +
> > +	platform_set_drvdata(pdev, pc);
> 
> No need to move the location of the platform_set_drvdata() call. It's
> needless churn.
> 
> >  static const struct of_device_id mtk_pwm_of_match[] = {
> > -	{ .compatible = "mediatek,mt7623-pwm" },
> > -	{ }
> > +	{.compatible = "mediatek,mt2712-pwm", .data = &mt2712_pwm_data},
> > +	{.compatible = "mediatek,mt7622-pwm", .data = &mt7622_pwm_data},
> > +	{.compatible = "mediatek,mt7623-pwm", .data = &mt7623_pwm_data},
> > +	{},
> 
> Spaces after { and before }, please.
> 
> Thierry