On Mon, Jun 10, 2024 at 06:06:51PM +0300, Andy Shevchenko wrote:
> Sat, Jun 08, 2024 at 05:16:33PM +0300, Laurent Pinchart kirjoitti:
> > From: Clark Wang <xiaoning.wang@xxxxxxx>
> >
> > The ADP5585 is a 10/11 input/output port expander with a built in keypad
> > matrix decoder, programmable logic, reset generator, and PWM generator.
> > This driver supports the PWM function using the platform device
> > registered by the core MFD driver.
> >
> > The driver is derived from an initial implementation from NXP, available
> > in commit 113113742208 ("MLK-25922-1 pwm: adp5585: add adp5585 PWM
> > support") in their BSP kernel tree. It has been extensively rewritten.
>
> ...
>
> > +#define ADP5585_PWM_OSC_FREQ_HZ 1000000U
>
> (1 * HZ_PER_MHZ) ?
>
> Variant to use MEGA. Or even #define MHz in units.h if you wish.
> Putting a few 0:s in a row is error prone.
Feel free to send follow-up patches.
Andy, we're reaching a level of nitpicking and yakshaving that even I
can't deal with. I will have to simply ignore the comments I disagree
with.
> ...
>
> > + ret = regmap_write(regmap, ADP5585_PWM_OFFT_LOW,
> > + off & 0xff);
> > + if (ret)
> > + return ret;
> > + ret = regmap_write(regmap, ADP5585_PWM_OFFT_HIGH,
> > + (off >> 8) & 0xff);
> > + if (ret)
> > + return ret;
>
> This is regular I²C regmap, why do you avoid using regmap bulk APIs?
>
> > + ret = regmap_write(regmap, ADP5585_PWM_ONT_LOW,
> > + on & 0xff);
> > + if (ret)
> > + return ret;
> > + ret = regmap_write(regmap, ADP5585_PWM_ONT_HIGH,
> > + (on >> 8) & 0xff);
> > + if (ret)
> > + return ret;
>
> Ditto.
>
> ...
>
> > +static int pwm_adp5585_get_state(struct pwm_chip *chip,
> > + struct pwm_device *pwm,
> > + struct pwm_state *state)
> > +{
> > + struct regmap *regmap = pwmchip_get_drvdata(chip);
> > + unsigned int on, off;
> > + unsigned int val;
> > +
> > + regmap_read(regmap, ADP5585_PWM_OFFT_LOW, &off);
> > + regmap_read(regmap, ADP5585_PWM_OFFT_HIGH, &val);
> > + off |= val << 8;
>
> Ditto.
>
> > + regmap_read(regmap, ADP5585_PWM_ONT_LOW, &on);
> > + regmap_read(regmap, ADP5585_PWM_ONT_HIGH, &val);
> > + on |= val << 8;
>
> Ditto.
>
> > + state->duty_cycle = on * (NSEC_PER_SEC / ADP5585_PWM_OSC_FREQ_HZ);
> > + state->period = (on + off) * (NSEC_PER_SEC / ADP5585_PWM_OSC_FREQ_HZ);
> > +
> > + state->polarity = PWM_POLARITY_NORMAL;
> > +
> > + regmap_read(regmap, ADP5585_PWM_CFG, &val);
> > + state->enabled = !!(val & ADP5585_PWM_EN);
> > +
> > + return 0;
>
> Besides that, how do you guarantee that no IO may happen in between of those
> calls? Probably you want a driver explicit lock? In that case, would you still
> want to have a regmap internal lock?
>
> > +}
>
> ...
>
> > +static int adp5585_pwm_probe(struct platform_device *pdev)
> > +{
> > + struct device *dev = &pdev->dev;
> > + struct adp5585_dev *adp5585 = dev_get_drvdata(dev->parent);
> > + struct pwm_chip *chip;
> > + int ret;
> > +
> > + chip = devm_pwmchip_alloc(dev, ADP5585_PWM_CHAN_NUM, 0);
> > + if (IS_ERR(chip))
> > + return PTR_ERR(chip);
>
> > + device_set_of_node_from_dev(dev, dev->parent);
>
> Still unclear to me why only few drivers use this.
>
> > + pwmchip_set_drvdata(chip, adp5585->regmap);
> > + chip->ops = &adp5585_pwm_ops;
> > +
> > + ret = devm_pwmchip_add(dev, chip);
> > + if (ret)
> > + return dev_err_probe(dev, ret, "failed to add PWM chip\n");
> > +
> > + return 0;
> > +}
>
> ...
>
> > +static const struct platform_device_id adp5585_pwm_id_table[] = {
> > + { "adp5585-pwm" },
> > + { /* Sentinel */ },
>
> Drop comma. Otherwise it's not a sentinel strictly speaking.
>
> > +};
--
Regards,
Laurent Pinchart
