[PATCH] pinctrl: core: print gpio in pins debugfs file

[Drew Fustini <drew@xxxxxxxxxxxxxxx>]

If there is a gpio range mapping for the pin, then print out the gpio
number for the pin in the debugfs 'pins' file.

Here is an example output on the BeagleBone Black from:
/sys/kernel/debug/pinctrl/44e10800.pinmux-pinctrl-single/pins

pin 103 (PIN103) GPIO-113 44e1099c 00000027 pinctrl-single
pin 104 (PIN104) GPIO-114 44e109a0 0000002c pinctrl-single
pin 105 (PIN105) GPIO-115 44e109a4 00000027 pinctrl-single
pin 106 (PIN106) GPIO-116 44e109a8 00000027 pinctrl-single
pin 107 (PIN107) GPIO-117 44e109ac 00000027 pinctrl-single
pin 108 (PIN108) GPIO-19 44e109b0 00000027 pinctrl-single
pin 109 (PIN109) GPIO-20 44e109b4 00000027 pinctrl-single
pin 110 (PIN110) 44e109b8 00000030 pinctrl-single
pin 111 (PIN111) 44e109bc 00000028 pinctrl-single
pin 112 (PIN112) 44e109c0 00000030 pinctrl-single
pin 113 (PIN113) 44e109c4 00000028 pinctrl-single
pin 114 (PIN114) 44e109c8 00000028 pinctrl-single

Suggested-by: Andy Shevchenko <andy.shevchenko@xxxxxxxxx>
Suggested-by: Tony Lindgren <tony@xxxxxxxxxxx>
Signed-off-by: Drew Fustini <drew@xxxxxxxxxxxxxxx>
---
Note:
- I am hoping to get feedback if another format is better.  Currently
  the column 'GPIO-xxx' will only be printed when there is a GPIO num

 drivers/pinctrl/core.c | 12 ++++++++++++
 1 file changed, 12 insertions(+)

diff --git a/drivers/pinctrl/core.c b/drivers/pinctrl/core.c
index 70e13fcd94c4..e3eee950a553 100644
--- a/drivers/pinctrl/core.c
+++ b/drivers/pinctrl/core.c
@@ -1633,6 +1633,8 @@ static int pinctrl_pins_show(struct seq_file *s, void *what)
 	struct pinctrl_dev *pctldev = s->private;
 	const struct pinctrl_ops *ops = pctldev->desc->pctlops;
 	unsigned i, pin;
+	struct pinctrl_gpio_range *range;
+	unsigned gpio_num;
 
 	seq_printf(s, "registered pins: %d\n", pctldev->desc->npins);
 
@@ -1650,6 +1652,16 @@ static int pinctrl_pins_show(struct seq_file *s, void *what)
 
 		seq_printf(s, "pin %d (%s) ", pin, desc->name);
 
+		gpio_num = 0;
+		list_for_each_entry(range, &pctldev->gpio_ranges, node) {
+			if ((pin >= range->pin_base) &&
+			    (pin < (range->pin_base + range->npins)))
+				gpio_num = range->base + (pin - range->pin_base);
+		}
+
+		if (gpio_num > 0)
+			seq_printf(s, "GPIO-%u ", gpio_num);
+
 		/* Driver-specific info per pin */
 		if (ops->pin_dbg_show)
 			ops->pin_dbg_show(pctldev, s, pin);
-- 
2.25.1