Re: [PATCH v7 4/4] pinctrl: Implementation of the generic scmi-pinctrl driver

[Andy Shevchenko <andriy.shevchenko@xxxxxxxxx>]

On Tue, Apr 02, 2024 at 10:22:24AM +0800, Peng Fan (OSS) wrote:
> From: Peng Fan <peng.fan@xxxxxxx>
> 
> scmi-pinctrl driver implements pinctrl driver interface and using
> SCMI protocol to redirect messages from pinctrl subsystem SDK to
> SCMI platform firmware, which does the changes in HW.

...

> +#include <linux/device.h>
> +#include <linux/err.h>
> +#include <linux/module.h>
> +#include <linux/seq_file.h>
> +#include <linux/scmi_protocol.h>
> +#include <linux/slab.h>

Missing headers.

...

> +	*p_groups = (const char * const *)func->groups;

Is this casting needed?

...

> +static int pinctrl_scmi_pinconf_get(struct pinctrl_dev *pctldev,
> +				    unsigned int _pin, unsigned long *config)

Why underscored parameter name?

...

> +static int pinctrl_scmi_get_pins(struct scmi_pinctrl *pmx,
> +				 struct pinctrl_desc *desc)
> +{
> +	struct pinctrl_pin_desc *pins;
> +	unsigned int npins;
> +	int ret, i;
> +
> +	npins = pinctrl_ops->count_get(pmx->ph, PIN_TYPE);
> +	/*
> +	 * npins will never be zero, the scmi pinctrl driver has bailed out
> +	 * if npins is zero.
> +	 */

This is fragile, but at least it is documented.

> +	pins = devm_kmalloc_array(pmx->dev, npins, sizeof(*pins), GFP_KERNEL);
> +	if (!pins)
> +		return -ENOMEM;
> +
> +	for (i = 0; i < npins; i++) {
> +		pins[i].number = i;
> +		ret = pinctrl_ops->name_get(pmx->ph, i, PIN_TYPE, &pins[i].name);
> +		if (ret)

How does the cleanup work for the previously assigned pin names? Is it needed?
Maybe a comment?

> +			return dev_err_probe(pmx->dev, ret,
> +					     "Can't get name for pin %d", i);
> +	}
> +
> +	desc->npins = npins;
> +	desc->pins = pins;
> +	dev_dbg(pmx->dev, "got pins %u", npins);
> +
> +	return 0;
> +}

...

> +static const struct scmi_device_id scmi_id_table[] = {
> +	{ SCMI_PROTOCOL_PINCTRL, "pinctrl" },
> +	{ }
> +};
> +MODULE_DEVICE_TABLE(scmi, scmi_id_table);

Move this closer to the user.

-- 
With Best Regards,
Andy Shevchenko