Re: [PATCH 3/3] pinctrl: qcom: Don't allow protected pins to be requested

From: Bjorn Andersson
Date: Wed Jan 10 2018 - 01:11:47 EST


On Tue 09 Jan 17:58 PST 2018, Stephen Boyd wrote:

I like it, a few comment below though.

> +static int msm_gpio_init_irq_valid_mask(struct gpio_chip *chip,
> + struct msm_pinctrl *pctrl)
> +{
> + int ret;
> + unsigned int len, i;
> + unsigned int max_gpios = pctrl->soc->ngpios;
> + struct device_node *np = pctrl->dev->of_node;
> +
> + /* The number of GPIOs in the ACPI tables */
> + ret = device_property_read_u16_array(pctrl->dev, "gpios", NULL, 0);
> + if (ret > 0 && ret < max_gpios) {
> + u16 *tmp;
> +
> + len = ret;
> + tmp = kmalloc_array(len, sizeof(tmp[0]), GFP_KERNEL);
> + if (!tmp)
> + return -ENOMEM;
> +
> + ret = device_property_read_u16_array(pctrl->dev, "gpios", tmp,
> + len);
> + if (ret < 0) {
> + dev_err(pctrl->dev, "could not read list of GPIOs\n");
> + kfree(tmp);
> + return ret;
> + }
> +
> + bitmap_zero(chip->irq_valid_mask, max_gpios);

The valid_mask is moving into the gpio_irq_chip, so this should be
chip->irq.valid_mask.

See dc7b0387ee89 ("gpio: Move irq_valid_mask into struct gpio_irq_chip")

> + for (i = 0; i < len; i++)
> + set_bit(tmp[i], chip->irq_valid_mask);
> +

You're leaking tmp here.

> + return 0;
> + }
> +
> + /* If there's a DT ngpios-ranges property then add those ranges */
> + ret = of_property_count_u32_elems(np, "ngpios-ranges");
> + if (ret > 0 && ret % 2 == 0 && ret / 2 < max_gpios) {
> + u32 start;
> + u32 count;
> +
> + len = ret / 2;
> + bitmap_zero(chip->irq_valid_mask, max_gpios);
> +
> + for (i = 0; i < len; i++) {

If you take steps of 2, when looping from 0 to ret, your loop index will
have the value that you're passing as index into the read - without
duplicating it.

> + of_property_read_u32_index(np, "ngpios-ranges",
> + i * 2, &start);
> + of_property_read_u32_index(np, "ngpios-ranges",
> + i * 2 + 1, &count);
> + bitmap_set(chip->irq_valid_mask, start, count);
> + }
> + }
> +
> + return 0;
> +}
[..]
> @@ -824,6 +907,7 @@ static int msm_gpio_init(struct msm_pinctrl *pctrl)
> chip->parent = pctrl->dev;
> chip->owner = THIS_MODULE;
> chip->of_node = pctrl->dev->of_node;
> + chip->irq_need_valid_mask = msm_gpio_needs_irq_valid_mask(pctrl);

chip->irq.need_valid_mask

>
> ret = gpiochip_add_data(&pctrl->chip, pctrl);
> if (ret) {
> @@ -831,6 +915,12 @@ static int msm_gpio_init(struct msm_pinctrl *pctrl)
> return ret;
> }
>
> + ret = msm_gpio_init_irq_valid_mask(chip, pctrl);
> + if (ret) {
> + dev_err(pctrl->dev, "Failed to setup irq valid bits\n");

gpiochip_remove() here, to release resources allocated by
gpiochip_add_data.

> + return ret;
> + }
> +
> ret = gpiochip_add_pin_range(&pctrl->chip, dev_name(pctrl->dev), 0, 0, chip->ngpio);
> if (ret) {
> dev_err(pctrl->dev, "Failed to add pin range\n");

Regards,
Bjorn