[PATCH v2 1/3] gpio: brcmstb: correct hwirq to bank map

Florian Fainelli posted 3 patches 1 week, 4 days ago
[PATCH v2 1/3] gpio: brcmstb: correct hwirq to bank map
Posted by Florian Fainelli 1 week, 4 days ago
From: Doug Berger <opendmb@gmail.com>

The brcmstb_gpio_hwirq_to_bank() function was designed to
accommodate the downward numbering of dynamic GPIOs by
traversing the bank list in the reverse order. However, the
dynamic numbering has changed to increment upward which can
produce an incorrect mapping.

The function is modified to no longer assume an ordering of
the list to accommodate either option.

Fixes: 7b61212f2a07 ("gpiolib: Get rid of ARCH_NR_GPIOS")
Signed-off-by: Doug Berger <opendmb@gmail.com>
Signed-off-by: Florian Fainelli <florian.fainelli@broadcom.com>
---
 drivers/gpio/gpio-brcmstb.c | 8 +++-----
 1 file changed, 3 insertions(+), 5 deletions(-)

diff --git a/drivers/gpio/gpio-brcmstb.c b/drivers/gpio/gpio-brcmstb.c
index af9287ff5dc4..2352d099709c 100644
--- a/drivers/gpio/gpio-brcmstb.c
+++ b/drivers/gpio/gpio-brcmstb.c
@@ -301,12 +301,10 @@ static struct brcmstb_gpio_bank *brcmstb_gpio_hwirq_to_bank(
 		struct brcmstb_gpio_priv *priv, irq_hw_number_t hwirq)
 {
 	struct brcmstb_gpio_bank *bank;
-	int i = 0;
 
-	/* banks are in descending order */
-	list_for_each_entry_reverse(bank, &priv->bank_list, node) {
-		i += bank->chip.gc.ngpio;
-		if (hwirq < i)
+	list_for_each_entry(bank, &priv->bank_list, node) {
+		if (hwirq >= bank->chip.gc.offset &&
+		    hwirq < (bank->chip.gc.offset + bank->chip.gc.ngpio))
 			return bank;
 	}
 	return NULL;
-- 
2.43.0
Re: [PATCH v2 1/3] gpio: brcmstb: correct hwirq to bank map
Posted by Linus Walleij 1 week, 4 days ago
On Tue, Jan 27, 2026 at 10:47 PM Florian Fainelli
<florian.fainelli@broadcom.com> wrote:

> From: Doug Berger <opendmb@gmail.com>
>
> The brcmstb_gpio_hwirq_to_bank() function was designed to
> accommodate the downward numbering of dynamic GPIOs by
> traversing the bank list in the reverse order. However, the
> dynamic numbering has changed to increment upward which can
> produce an incorrect mapping.
>
> The function is modified to no longer assume an ordering of
> the list to accommodate either option.
>
> Fixes: 7b61212f2a07 ("gpiolib: Get rid of ARCH_NR_GPIOS")
> Signed-off-by: Doug Berger <opendmb@gmail.com>
> Signed-off-by: Florian Fainelli <florian.fainelli@broadcom.com>

This looks right.
Reviewed-by: Linus Walleij <linusw@kernel.org>

Yours,
Linus Walleij