On Wed, Jan 24, 2024 at 3:59 PM Paul Cercueil <paul@xxxxxxxxxxxxxxx> wrote:
>
> Hi Bartosz,
>
> Le mardi 05 septembre 2023 à 20:53 +0200, Bartosz Golaszewski a écrit :
> > From: Bartosz Golaszewski <bartosz.golaszewski@xxxxxxxxxx>
> >
> > We're porting all users of gpiochip_find() to using
> > gpio_device_find().
> > Update the swnode GPIO code.
> >
> > Signed-off-by: Bartosz Golaszewski <bartosz.golaszewski@xxxxxxxxxx>
> > ---
> > drivers/gpio/gpiolib-swnode.c | 29 ++++++++++++-----------------
> > 1 file changed, 12 insertions(+), 17 deletions(-)
> >
> > diff --git a/drivers/gpio/gpiolib-swnode.c b/drivers/gpio/gpiolib-
> > swnode.c
> > index b5a6eaf3729b..56c8519be538 100644
> > --- a/drivers/gpio/gpiolib-swnode.c
> > +++ b/drivers/gpio/gpiolib-swnode.c
> > @@ -31,31 +31,26 @@ static void swnode_format_propname(const char
> > *con_id, char *propname,
> > strscpy(propname, "gpios", max_size);
> > }
> >
> > -static int swnode_gpiochip_match_name(struct gpio_chip *chip, void
> > *data)
> > +static struct gpio_device *swnode_get_gpio_device(struct
> > fwnode_handle *fwnode)
> > {
> > - return !strcmp(chip->label, data);
> > -}
> > + const struct software_node *gdev_node;
> > + struct gpio_device *gdev;
> >
> > -static struct gpio_chip *swnode_get_chip(struct fwnode_handle
> > *fwnode)
> > -{
> > - const struct software_node *chip_node;
> > - struct gpio_chip *chip;
> > -
> > - chip_node = to_software_node(fwnode);
> > - if (!chip_node || !chip_node->name)
> > + gdev_node = to_software_node(fwnode);
> > + if (!gdev_node || !gdev_node->name)
> > return ERR_PTR(-EINVAL);
> >
> > - chip = gpiochip_find((void *)chip_node->name,
> > swnode_gpiochip_match_name);
> > - return chip ?: ERR_PTR(-EPROBE_DEFER);
> > + gdev = gpio_device_find_by_label((void *)gdev_node->name);
> > + return gdev ?: ERR_PTR(-EPROBE_DEFER);
> > }
> >
> > struct gpio_desc *swnode_find_gpio(struct fwnode_handle *fwnode,
> > const char *con_id, unsigned int
> > idx,
> > unsigned long *flags)
> > {
> > + struct gpio_device *gdev __free(gpio_device_put) = NULL;
> > const struct software_node *swnode;
> > struct fwnode_reference_args args;
> > - struct gpio_chip *chip;
> > struct gpio_desc *desc;
> > char propname[32]; /* 32 is max size of property name */
> > int error;
> > @@ -77,12 +72,12 @@ struct gpio_desc *swnode_find_gpio(struct
> > fwnode_handle *fwnode,
> > return ERR_PTR(error);
> > }
> >
> > - chip = swnode_get_chip(args.fwnode);
> > + gdev = swnode_get_gpio_device(args.fwnode);
> > fwnode_handle_put(args.fwnode);
> > - if (IS_ERR(chip))
> > - return ERR_CAST(chip);
> > + if (IS_ERR(gdev))
> > + return ERR_CAST(gdev);
>
> I'm a bit late to the party, sorry.
>
> I'm looking at how __free() should be used to use it in my own
> patchset, and I was wondering if this code actually works.
>
> What happens if swnode_get_gpio_device() returns an error pointer?
> Won't that cause a call to gpio_device_put() with the invalid pointer?
>
> Cheers,
> -Paul
>
No. because the __free() callback is defined as:
DEFINE_FREE(gpio_device_put, struct gpio_device *,
if (!IS_ERR_OR_NULL(_T)) gpio_device_put(_T))
Bart
> >
> > - desc = gpiochip_get_desc(chip, args.args[0]);
> > + desc = gpiochip_get_desc(gdev->chip, args.args[0]);
> > *flags = args.args[1]; /* We expect native GPIO flags */
> >
> > pr_debug("%s: parsed '%s' property of node '%pfwP[%d]' -
> > status (%d)\n",
>
