[PATCH 5.15 125/181] USB: bcma: Make GPIO explicitly optional

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From: Linus Walleij <linus.walleij@xxxxxxxxxx>

commit cd136706b4f925aa5d316642543babac90d45910 upstream.

What the code does is to not check the return value from
devm_gpiod_get() and then avoid using an erroneous GPIO descriptor
with IS_ERR_OR_NULL().

This will miss real errors from the GPIO core that should not be
ignored, such as probe deferral.

Instead request the GPIO as explicitly optional, which means that
if it doesn't exist, the descriptor returned will be NULL.

Then we can add error handling and also avoid just doing this on
the device tree path, and simplify the site where the optional
GPIO descriptor is used.

There were some problems with cleaning up this GPIO descriptor
use in the past, but this is the proper way to deal with it.

Cc: Rafał Miłecki <rafal@xxxxxxxxxx>
Cc: Chuhong Yuan <hslester96@xxxxxxxxx>
Signed-off-by: Linus Walleij <linus.walleij@xxxxxxxxxx>
Cc: stable <stable@xxxxxxxxxx>
Link: https://lore.kernel.org/r/20221107090753.1404679-1-linus.walleij@xxxxxxxxxx
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
---
 drivers/usb/host/bcma-hcd.c |   10 ++++++----
 1 file changed, 6 insertions(+), 4 deletions(-)

--- a/drivers/usb/host/bcma-hcd.c
+++ b/drivers/usb/host/bcma-hcd.c
@@ -285,7 +285,7 @@ static void bcma_hci_platform_power_gpio
 {
 	struct bcma_hcd_device *usb_dev = bcma_get_drvdata(dev);
 
-	if (IS_ERR_OR_NULL(usb_dev->gpio_desc))
+	if (!usb_dev->gpio_desc)
 		return;
 
 	gpiod_set_value(usb_dev->gpio_desc, val);
@@ -406,9 +406,11 @@ static int bcma_hcd_probe(struct bcma_de
 		return -ENOMEM;
 	usb_dev->core = core;
 
-	if (core->dev.of_node)
-		usb_dev->gpio_desc = devm_gpiod_get(&core->dev, "vcc",
-						    GPIOD_OUT_HIGH);
+	usb_dev->gpio_desc = devm_gpiod_get_optional(&core->dev, "vcc",
+						     GPIOD_OUT_HIGH);
+	if (IS_ERR(usb_dev->gpio_desc))
+		return dev_err_probe(&core->dev, PTR_ERR(usb_dev->gpio_desc),
+				     "error obtaining VCC GPIO");
 
 	switch (core->id.id) {
 	case BCMA_CORE_USB20_HOST:





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