Re: [PATCH v6 10/12] watchdog: add gpio watchdog driver

Wolfgang Denk
2021-08-19T11:46:49Z

Dear Rasmus,

again: error handling.

In message <20210819095706.3585923-11-rasmus.villemoes@prevas.dk> you wrote:
>
> diff --git a/drivers/watchdog/gpio_wdt.c b/drivers/watchdog/gpio_wdt.c
> new file mode 100644
> index 0000000000..982a66b3f9
> --- /dev/null
> +++ b/drivers/watchdog/gpio_wdt.c
> @@ -0,0 +1,68 @@
> +// SPDX-License-Identifier: GPL-2.0+
> +
> +#include <dm.h>
> +#include <dm/device_compat.h>
> +#include <wdt.h>
> +#include <asm/gpio.h>
> +
> +struct gpio_wdt_priv {
> + struct gpio_desc gpio;
> + bool always_running;
> + int state;
> +};
> +
> +static int gpio_wdt_reset(struct udevice *dev)
> +{
> + struct gpio_wdt_priv *priv = dev_get_priv(dev);
> +
> + priv->state = !priv->state;

Potential NULL pointer dereference.

> +static int gpio_wdt_start(struct udevice *dev, u64 timeout, ulong flags)
> +{
> + struct gpio_wdt_priv *priv = dev_get_priv(dev);
> +
> + if (priv->always_running)
> + return 0;

Ditto.

> +static int dm_probe(struct udevice *dev)
> +{
> + struct gpio_wdt_priv *priv = dev_get_priv(dev);
> + int ret;
> +
> + priv->always_running = dev_read_bool(dev, "always-running");

Ditto.

> + ret = gpio_request_by_name(dev, "gpios", 0, &priv->gpio, GPIOD_IS_OUT);
> + if (ret < 0) {
> + dev_err(dev, "Request for wdt gpio failed: %d\n", ret);
> + return ret;
> + }
> +
> + if (priv->always_running)
> + ret = gpio_wdt_reset(dev);

Ditto.

Best regards,

Wolfgang Denk

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