4.9-stable review patch. If anyone has any objections, please let me know.
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From: Linus Walleij linus.walleij@linaro.org
commit 7d18f0a14aa6a0d6bad39111c1fb655f07f71d59 upstream.
Sometimes a GPIO is fetched with NULL as parent device, and that is just fine. So under these circumstances, avoid using dev_name() to provide a name for the GPIO line.
Signed-off-by: Linus Walleij linus.walleij@linaro.org Cc: Daniel Rosenberg drosen@google.com Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org
--- drivers/gpio/gpiolib.c | 9 +++++++-- 1 file changed, 7 insertions(+), 2 deletions(-)
--- a/drivers/gpio/gpiolib.c +++ b/drivers/gpio/gpiolib.c @@ -3204,6 +3204,8 @@ struct gpio_desc *__must_check gpiod_get struct gpio_desc *desc = NULL; int status; enum gpio_lookup_flags lookupflags = 0; + /* Maybe we have a device name, maybe not */ + const char *devname = dev ? dev_name(dev) : "?";
dev_dbg(dev, "GPIO lookup for consumer %s\n", con_id);
@@ -3232,8 +3234,11 @@ struct gpio_desc *__must_check gpiod_get return desc; }
- /* If a connection label was passed use that, else use the device name as label */ - status = gpiod_request(desc, con_id ? con_id : dev_name(dev)); + /* + * If a connection label was passed use that, else attempt to use + * the device name as label + */ + status = gpiod_request(desc, con_id ? con_id : devname); if (status < 0) return ERR_PTR(status);