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

[Peng Fan <peng.fan@xxxxxxx>]

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

Not sure there is an easy way to filter out what is missed.

> 
> ...
> 
> > +	*p_groups = (const char * const *)func->groups;
> 
> Is this casting needed?

This is no needed.

> 
> ...
> 
> > +static int pinctrl_scmi_pinconf_get(struct pinctrl_dev *pctldev,
> > +				    unsigned int _pin, unsigned long *config)
> 
> Why underscored parameter name?

Underscore could be dropped.

> 
> ...
> 
> > +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?

No need. The "name" memory region is allocated in firmware pinctrl
Protocol init phase.

> Maybe a comment?

ok.  As below.
/*
 * The region for name is handled by the scmi firmware driver, 
 * no need free here
*/

> 
> > +			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.

ok. Fix in v8.

Thanks,
Peng.
> 
> --
> With Best Regards,
> Andy Shevchenko
>