Re: [PATCH v7 03/11] pinctrl: Add MAX7360 pinctrl driver

[Andy Shevchenko]

On Mon, Apr 28, 2025 at 01:57:21PM +0200, Mathieu Dubois-Briand wrote:
> Add driver for Maxim Integrated MAX7360 pinctrl on the PORT pins. Pins
> can be used either for GPIO, PWM or rotary encoder functionalities.

...

> +#include <linux/array_size.h>

> +#include <linux/dev_printk.h>
> +#include <linux/device.h>
> +#include <linux/device/devres.h>

Since device.h is included the other two are not strictly needed, but it's fine
to leave them explicitly included.

> +#include <linux/err.h>
> +#include <linux/init.h>
> +#include <linux/mfd/max7360.h>
> +#include <linux/module.h>
> +#include <linux/platform_device.h>
> +#include <linux/regmap.h>

> +#include <linux/slab.h>

Is it used?

...

> +struct max7360_pinctrl {
> +	struct pinctrl_dev *pctldev;
> +	struct pinctrl_desc pinctrl_desc;

Does`pahole` agree with your choice of layout?

> +};

...

> +static int max7360_set_mux(struct pinctrl_dev *pctldev, unsigned int selector,
> +			   unsigned int group)
> +{
> +	struct regmap *regmap;
> +	int val;
> +
> +	/*
> +	 * GPIO and PWM functions are the same: we only need to handle the
> +	 * rotary encoder function, on pins 6 and 7.
> +	 */
> +	if (max7360_groups[group].pins[0] >= 6) {
> +		if (selector == MAX7360_PINCTRL_FN_ROTARY)
> +			val = MAX7360_GPIO_CFG_RTR_EN;
> +		else
> +			val = 0;

> +		regmap = dev_get_regmap(pctldev->dev->parent, NULL);

This assignment can be unified with the definition above.

> +		return regmap_write_bits(regmap, MAX7360_REG_GPIOCFG, MAX7360_GPIO_CFG_RTR_EN, val);
> +	}
> +
> +	return 0;
> +}

...

> +static int max7360_pinctrl_probe(struct platform_device *pdev)
> +{
> +	struct regmap *regmap;
> +	struct pinctrl_desc *pd;
> +	struct max7360_pinctrl *chip;
> +	struct device *dev = &pdev->dev;
> +
> +	regmap = dev_get_regmap(dev->parent, NULL);
> +	if (!regmap)
> +		dev_err_probe(dev, -ENODEV, "Could not get parent regmap\n");

Missing 'return'. Or...?

> +	chip = devm_kzalloc(dev, sizeof(*chip), GFP_KERNEL);
> +	if (!chip)
> +		return -ENOMEM;
> +
> +	pd = &chip->pinctrl_desc;
> +
> +	pd->pctlops = &max7360_pinctrl_ops;
> +	pd->pmxops = &max7360_pmxops;
> +	pd->name = dev_name(dev);
> +	pd->pins = max7360_pins;
> +	pd->npins = MAX7360_MAX_GPIO;
> +	pd->owner = THIS_MODULE;
> +
> +	device_set_of_node_from_dev(dev, dev->parent);

I don't like this, but I have no better idea right now. Perhaps add a comment
on top to explain this call?

> +	chip->pctldev = devm_pinctrl_register(dev, pd, chip);
> +	if (IS_ERR(chip->pctldev))
> +		return dev_err_probe(dev, PTR_ERR(chip->pctldev), "can't register controller\n");
> +
> +	return 0;
> +}

-- 
With Best Regards,
Andy Shevchenko