[PATCH AUTOSEL 4.19 077/146] gpio: brcmstb: allow 0 width GPIO banks

Sasha Levin
2018-10-31T23:47:36Z

From: Justin Chen <justinpopo6@gmail.com>

[ Upstream commit bfba223dcc4548632d8f3bfd15690a86d4c68504 ]

Sometimes we have empty banks within the GPIO block. This commit allows
proper handling of 0 width GPIO banks. We handle 0 width GPIO banks by
incrementing the bank and number of GPIOs, but not initializing them.
This will mean a call into the non-existent GPIOs will return an error.

Also remove "GPIO registered" dev print. This information is misleading
since the incremented banks and gpio_base do not reflect the actual GPIOs
that get initialized. We leave this information out since it is already
printed with dev_dbg.

Signed-off-by: Justin Chen <justinpopo6@gmail.com>
Acked-by: Florian Fainelli <f.fainelli@gmail.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
drivers/gpio/gpio-brcmstb.c | 15 ++++++++++++---
1 file changed, 12 insertions(+), 3 deletions(-)

diff --git a/drivers/gpio/gpio-brcmstb.c b/drivers/gpio/gpio-brcmstb.c
index 16c7f9f49416..af936dcca659 100644
--- a/drivers/gpio/gpio-brcmstb.c
+++ b/drivers/gpio/gpio-brcmstb.c
@@ -664,6 +664,18 @@ static int brcmstb_gpio_probe(struct platform_device *pdev)
struct brcmstb_gpio_bank *bank;
struct gpio_chip *gc;

+ /*
+ * If bank_width is 0, then there is an empty bank in the
+ * register block. Special handling for this case.
+ */
+ if (bank_width == 0) {
+ dev_dbg(dev, "Width 0 found: Empty bank @ %d\n",
+ num_banks);
+ num_banks++;
+ gpio_base += MAX_GPIO_PER_BANK;
+ continue;
+ }
+
bank = devm_kzalloc(dev, sizeof(*bank), GFP_KERNEL);
if (!bank) {
err = -ENOMEM;
@@ -740,9 +752,6 @@ static int brcmstb_gpio_probe(struct platform_device *pdev)
goto fail;
}

- dev_info(dev, "Registered %d banks (GPIO(s): %d-%d)\n",
- num_banks, priv->gpio_base, gpio_base - 1);
-
if (priv->parent_wake_irq && need_wakeup_event)
pm_wakeup_event(dev, 0);

--
2.17.1