pinctrl: Add -l (list) mode

Like i2cdetect -l and gpioinfo -l, pinctrl -l just lists the detected
compatible GPIO chips.

Signed-off-by: Phil Elwell <[email protected]>

Author: pelwell

pinctrl/pinctrl.c

@@ -82,6 +82,8 @@ static void usage(void)
     printf("  %s [-p] [-v] lev [GPIO]\n", name);
     printf("OR\n");
     printf("  %s -c <chip> [funcs] [GPIO]\n", name);
+    printf("OR\n");
+    printf("  %s -l\n", name);
     printf("\n");
     printf("GPIO is a comma-separated list of GPIO names, numbers or ranges (without\n");
     printf("spaces), e.g. 4 or 18-21 or BT_ON,9-11\n");
@@ -94,6 +96,7 @@ static void usage(void)
     printf("or if [GPIO] is specified the alternate funcs just for that specific GPIO.\n");
     printf("The -c option allows the alt functions (and only the alt function) for a named\n");
     printf("chip to be displayed, even if that chip is not present in the current system.\n");
+    printf("The -l option lists the discovered chips.\n");
     printf("\n");
     printf("Valid [options] for %s set are:\n", name);
     printf("  ip      set GPIO as input\n");
@@ -119,6 +122,7 @@ static void usage(void)
     printf("  %s set 20 op pn dh  Set GPIO20 to output with no pull and driving high\n", name);
     printf("  %s lev 4            Prints the level (1 or 0) of GPIO4\n", name);
     printf("  %s -c bcm2835 9-11  Display the alt functions for GPIOs 9-11 on bcm2835\n", name);
+    printf("  %s -l               List the compatible detected GPIO chips\n", name);
 }
 
 static int do_gpio_get(unsigned int gpio)
@@ -338,6 +342,7 @@ int main(int argc, char *argv[])
     int poll = 0;
     int funcs = 0;
     int echo = 0;
+    int list = 0;
     int pull = PULL_MAX;
     int infer_cmd = 0;
     int fsparam = GPIO_FSEL_MAX;
@@ -355,33 +360,38 @@ int main(int argc, char *argv[])
         const char *arg = *(argv++);
         argc--;
 
-        if (strcmp(arg, "-h") == 0)
+        if (strcmp(arg, "-c") == 0)
+        {
+            if (!argc)
+            {
+                printf("* chip name expected - use 'pinctrl -h' for help\n");
+                return -1;
+            }
+            named_chip = *(argv++);
+            argc--;
+        }
+        else if (strcmp(arg, "-e") == 0)
+        {
+            echo = 1;
+        }
+        else if (strcmp(arg, "-h") == 0)
         {
             usage();
             return 0;
         }
-        else if (strcmp(arg, "-p") == 0)
+        else if (strcmp(arg, "-l") == 0)
         {
-            pin_mode = 1;
+            list = 1;
+            verbose_mode = 1;
         }
-        else if (strcmp(arg, "-e") == 0)
+        else if (strcmp(arg, "-p") == 0)
         {
-            echo = 1;
+            pin_mode = 1;
         }
         else if (strcmp(arg, "-v") == 0)
         {
             verbose_mode = 1;
         }
-        else if (strcmp(arg, "-c") == 0)
-        {
-            if (!argc)
-            {
-                printf("* chip name expected - use 'pinctrl -h' for help\n");
-                return -1;
-            }
-            named_chip = *(argv++);
-            argc--;
-        }
         else
         {
             printf("Unknown option '%s' - try \"%s help\"\n",
@@ -445,6 +455,9 @@ int main(int argc, char *argv[])
         get = 1;
     }
 
+    if (list)
+        return 0;
+
     if (pin_mode)
     {
        gpio_get_pin_range(&start_pin, &end_pin);