[PATCH 2/2] gpio: aggregator: Use bitmap_parselist() for parsing GPIO offsets

[Geert Uytterhoeven <geert+renesas@xxxxxxxxx>]

Replace the custom code to parse GPIO offsets and/or GPIO offset ranges
by a call to bitmap_parselist(), and an iteration over the returned bit
mask.

This should have no impact on the format of the configuration parameters
written to the "new_device" virtual file in sysfs.

Suggested-by: Andy Shevchenko <andy.shevchenko@xxxxxxxxx>
Signed-off-by: Geert Uytterhoeven <geert+renesas@xxxxxxxxx>
---
I'm not super happy with the mask[] array, which is on the stack.
But there is no real limit on the number of GPIO lines provided by a
single gpiochip, except for the global ARCH_NR_GPIOS.
---
 drivers/gpio/gpio-aggregator.c | 42 ++++++++++++----------------------
 1 file changed, 14 insertions(+), 28 deletions(-)

diff --git a/drivers/gpio/gpio-aggregator.c b/drivers/gpio/gpio-aggregator.c
index 62a3fcbd4b4bb106..7b2e7abaece9cdb1 100644
--- a/drivers/gpio/gpio-aggregator.c
+++ b/drivers/gpio/gpio-aggregator.c
@@ -10,6 +10,7 @@
 #include <linux/bitmap.h>
 #include <linux/bitops.h>
 #include <linux/ctype.h>
+#include <linux/gpio.h>
 #include <linux/gpio/consumer.h>
 #include <linux/gpio/driver.h>
 #include <linux/gpio/machine.h>
@@ -111,9 +112,10 @@ static int aggr_add_gpio(struct gpio_aggregator *aggr, const char *key,
 
 static int aggr_parse(struct gpio_aggregator *aggr)
 {
-	unsigned int first_index, last_index, i, n = 0;
-	char *name, *offsets, *first, *last, *next;
+	DECLARE_BITMAP(mask, ARCH_NR_GPIOS);
 	char *args = aggr->args;
+	unsigned int i, n = 0;
+	char *name, *offsets;
 	int error;
 
 	for (name = get_arg(&args), offsets = get_arg(&args); name;
@@ -134,32 +136,16 @@ static int aggr_parse(struct gpio_aggregator *aggr)
 		}
 
 		/* GPIO chip + offset(s) */
-		for (first = offsets; *first; first = next) {
-			next = strchrnul(first, ',');
-			if (*next)
-				*next++ = '\0';
-
-			last = strchr(first, '-');
-			if (last)
-				*last++ = '\0';
-
-			if (kstrtouint(first, 10, &first_index)) {
-				pr_err("Cannot parse GPIO index %s\n", first);
-				return -EINVAL;
-			}
-
-			if (!last) {
-				last_index = first_index;
-			} else if (kstrtouint(last, 10, &last_index)) {
-				pr_err("Cannot parse GPIO index %s\n", last);
-				return -EINVAL;
-			}
-
-			for (i = first_index; i <= last_index; i++) {
-				error = aggr_add_gpio(aggr, name, i, &n);
-				if (error)
-					return error;
-			}
+		error = bitmap_parselist(offsets, mask, ARCH_NR_GPIOS);
+		if (error) {
+			pr_err("Cannot parse %s: %d\n", offsets, error);
+			return error;
+		}
+
+		for_each_set_bit(i, mask, ARCH_NR_GPIOS) {
+			error = aggr_add_gpio(aggr, name, i, &n);
+			if (error)
+				return error;
 		}
 
 		name = get_arg(&args);
-- 
2.17.1