gpiolib: Add gpio name information to /sys/kernel/debug/gpio

Add some information about gpio names to the debugfs gpio file. name and
label of a GPIO are then displayed next to each other. This way it is
easy to see what the real name of GPIO is and what the driver requested
it for.

Signed-off-by: Markus Pargmann <mpa@pengutronix.de>
[Dropped unsolicited sysfs ABI patch hunk]
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>

drivers/gpio/gpiolib.c

@@ -2378,14 +2378,19 @@ static void gpiolib_dbg_show(struct seq_file *s, struct gpio_chip *chip)
 	int			is_irq;
 
 	for (i = 0; i < chip->ngpio; i++, gpio++, gdesc++) {
-		if (!test_bit(FLAG_REQUESTED, &gdesc->flags))
+		if (!test_bit(FLAG_REQUESTED, &gdesc->flags)) {
+			if (gdesc->name) {
+				seq_printf(s, " gpio-%-3d (%-20.20s)\n",
+					   gpio, gdesc->name);
+			}
 			continue;
+		}
 
 		gpiod_get_direction(gdesc);
 		is_out = test_bit(FLAG_IS_OUT, &gdesc->flags);
 		is_irq = test_bit(FLAG_USED_AS_IRQ, &gdesc->flags);
-		seq_printf(s, " gpio-%-3d (%-20.20s) %s %s %s",
+		seq_printf(s, " gpio-%-3d (%-20.20s|%-20.20s) %s %s %s",
-			gpio, gdesc->label,
+			gpio, gdesc->name ? gdesc->name : "", gdesc->label,
 			is_out ? "out" : "in ",
 			chip->get
 				? (chip->get(chip, i) ? "hi" : "lo")