Re: [PATCH] rtc-v3020: add ability to access v3020 chip with GPIOs

[Andrew Morton <akpm@linux-foundation.org>]

On Mon,  2 Mar 2009 13:40:57 +0200
Mike Rapoport <mike@compulab.co.il> wrote:

> +static int v3020_gpio_map(struct v3020 *chip, struct platform_device *pdev,
> +			  struct v3020_platform_data *pdata)
> +{
> +	int i, err;
> +
> +	v3020_gpio[V3020_CS].gpio = pdata->gpio_cs;
> +	v3020_gpio[V3020_WR].gpio = pdata->gpio_wr;
> +	v3020_gpio[V3020_RD].gpio = pdata->gpio_rd;
> +	v3020_gpio[V3020_IO].gpio = pdata->gpio_io;
> +
> +	for (i = 0; i < ARRAY_SIZE(v3020_gpio); i++) {
> +		err = gpio_request(v3020_gpio[i].gpio, v3020_gpio[i].name);
> +		if (err)
> +			goto err_request;
> +
> +		gpio_direction_output(v3020_gpio[i].gpio, 1);
> +	}
> +
> +	chip->gpio = v3020_gpio;
> +
> +	return 0;
> +
> +err_request:
> +	for (; i >= 0; i--)
> +		gpio_free(v3020_gpio[i].gpio);
> +
> +	return err;
> +}

It needs this fix, I think?


fix off-by-one in error path

--- a/drivers/rtc/rtc-v3020.c~rtc-v3020-add-ability-to-access-v3020-chip-with-gpios-fix
+++ a/drivers/rtc/rtc-v3020.c
@@ -136,7 +136,7 @@ static int v3020_gpio_map(struct v3020 *
 	return 0;
 
 err_request:
-	for (; i >= 0; i--)
+	while (--i >= 0)
 		gpio_free(v3020_gpio[i].gpio);
 
 	return err;