Le 17/06/2022 à 08:08, Liang He a écrit :
> In gpio_halt_probe(), of_find_matching_node() will return a node
> pointer with refcount incremented. We should use of_node_put() in
> fail path or when it is not used anymore.
>
> Signed-off-by: Liang He <[email protected]>
> ---
> changelog:
> v4: reuse exist 'err' and use a simple code style, advised by CJ
> v3: use local 'child_node' advised by Michael.
> v2: use goto-label patch style advised by Christophe Leroy.
> v1: add of_node_put() before each exit.
>
> arch/powerpc/platforms/85xx/sgy_cts1000.c | 35 ++++++++++++++---------
> 1 file changed, 22 insertions(+), 13 deletions(-)
>
> diff --git a/arch/powerpc/platforms/85xx/sgy_cts1000.c
> b/arch/powerpc/platforms/85xx/sgy_cts1000.c
> index 98ae64075193..e4588943fe7e 100644
> --- a/arch/powerpc/platforms/85xx/sgy_cts1000.c
> +++ b/arch/powerpc/platforms/85xx/sgy_cts1000.c
> @@ -71,6 +71,7 @@ static int gpio_halt_probe(struct platform_device *pdev)
> {
> enum of_gpio_flags flags;
> struct device_node *node = pdev->dev.of_node;
> + struct device_node *child_node;
> int gpio, err, irq;
> int trigger;
>
> @@ -78,26 +79,29 @@ static int gpio_halt_probe(struct platform_device *pdev)
> return -ENODEV;
>
> /* If there's no matching child, this isn't really an error */
> - halt_node = of_find_matching_node(node, child_match);
> - if (!halt_node)
> + child_node = of_find_matching_node(node, child_match);
> + if (!child_node)
> return 0;
>
> /* Technically we could just read the first one, but punish
> * DT writers for invalid form. */
> - if (of_gpio_count(halt_node) != 1)
> - return -EINVAL;
> + if (of_gpio_count(child_node) != 1) {
> + err = -EINVAL;
> + goto err_put;
> + }
>
> /* Get the gpio number relative to the dynamic base. */
> - gpio = of_get_gpio_flags(halt_node, 0, &flags);
> - if (!gpio_is_valid(gpio))
> - return -EINVAL;
> + gpio = of_get_gpio_flags(child_node, 0, &flags);
> + if (!gpio_is_valid(gpio)) {
> + err = -EINVAL;
> + gotot err_put;
Did you test the build ?
> + }
>
> err = gpio_request(gpio, "gpio-halt");
> if (err) {
> printk(KERN_ERR "gpio-halt: error requesting GPIO %d.\n",
> gpio);
> - halt_node = NULL;
> - return err;
> + goto err_put;
> }
>
> trigger = (flags == OF_GPIO_ACTIVE_LOW);
> @@ -105,15 +109,14 @@ static int gpio_halt_probe(struct platform_device *pdev)
> gpio_direction_output(gpio, !trigger);
>
> /* Now get the IRQ which tells us when the power button is hit */
> - irq = irq_of_parse_and_map(halt_node, 0);
> + irq = irq_of_parse_and_map(child_node, 0);
> err = request_irq(irq, gpio_halt_irq, IRQF_TRIGGER_RISING |
> - IRQF_TRIGGER_FALLING, "gpio-halt", halt_node);
> + IRQF_TRIGGER_FALLING, "gpio-halt", child_node);
> if (err) {
> printk(KERN_ERR "gpio-halt: error requesting IRQ %d for "
> "GPIO %d.\n", irq, gpio);
> gpio_free(gpio);
> - halt_node = NULL;
> - return err;
> + goto err_put;
> }
>
> /* Register our halt function */
> @@ -123,7 +126,12 @@ static int gpio_halt_probe(struct platform_device *pdev)
> printk(KERN_INFO "gpio-halt: registered GPIO %d (%d trigger, %d"
> " irq).\n", gpio, trigger, irq);
>
> + halt_node = child_node;
> return 0;
> +
> +err_put:
> + of_node_put(child_node);
> + return err;
> }
>
> static int gpio_halt_remove(struct platform_device *pdev)
> @@ -139,6 +147,7 @@ static int gpio_halt_remove(struct platform_device *pdev)
>
> gpio_free(gpio);
>
> + of_node_put(halt_node);
> halt_node = NULL;
> }
>
