gpio: add userspace ABI for GPIO line information

[linux-2.6-block.git] / tools / gpio / lsgpio.c

diff --git a/tools/gpio/lsgpio.c b/tools/gpio/lsgpio.c
index 692233f561fbd7abd59db6c6c985a9b7c82de891..5535ce81f8f75d080f11bf652880e9a6001e044b 100644 (file)
--- a/tools/gpio/lsgpio.c
+++ b/tools/gpio/lsgpio.c
@@ -26,12 +26,56 @@
 
 #include "gpio-utils.h"
 
+struct gpio_flag {
+       char *name;
+       unsigned long mask;
+};
+
+struct gpio_flag flagnames[] = {
+       {
+               .name = "kernel",
+               .mask = GPIOLINE_FLAG_KERNEL,
+       },
+       {
+               .name = "output",
+               .mask = GPIOLINE_FLAG_IS_OUT,
+       },
+       {
+               .name = "active-low",
+               .mask = GPIOLINE_FLAG_ACTIVE_LOW,
+       },
+       {
+               .name = "open-drain",
+               .mask = GPIOLINE_FLAG_OPEN_DRAIN,
+       },
+       {
+               .name = "open-source",
+               .mask = GPIOLINE_FLAG_OPEN_SOURCE,
+       },
+};
+
+void print_flags(unsigned long flags)
+{
+       int i;
+       int printed = 0;
+
+       for (i = 0; i < ARRAY_SIZE(flagnames); i++) {
+               if (flags & flagnames[i].mask) {
+                       if (printed)
+                               fprintf(stdout, " ");
+                       fprintf(stdout, "%s", flagnames[i].name);
+                       printed++;
+               }
+       }
+}
+
 int list_device(const char *device_name)
 {
        struct gpiochip_info cinfo;
        char *chrdev_name;
        int fd;
        int ret;
+       int i;
 
        ret = asprintf(&chrdev_name, "/dev/%s", device_name);
        if (ret < 0)
@@ -41,32 +85,55 @@ int list_device(const char *device_name)
        if (fd == -1) {
                ret = -errno;
                fprintf(stderr, "Failed to open %s\n", chrdev_name);
-               goto free_chrdev_name;
+               goto exit_close_error;
        }
 
        /* Inspect this GPIO chip */
        ret = ioctl(fd, GPIO_GET_CHIPINFO_IOCTL, &cinfo);
        if (ret == -1) {
                ret = -errno;
-               fprintf(stderr, "Failed to retrieve GPIO fd\n");
-               if (close(fd) == -1)
-                       perror("Failed to close GPIO character device file");
-
-               goto free_chrdev_name;
+               perror("Failed to issue CHIPINFO IOCTL\n");
+               goto exit_close_error;
        }
        fprintf(stdout, "GPIO chip: %s, \"%s\", %u GPIO lines\n",
                cinfo.name, cinfo.label, cinfo.lines);
 
-       if (close(fd) == -1)  {
-               ret = -errno;
-               goto free_chrdev_name;
+       /* Loop over the lines and print info */
+       for (i = 0; i < cinfo.lines; i++) {
+               struct gpioline_info linfo;
+
+               memset(&linfo, 0, sizeof(linfo));
+               linfo.line_offset = i;
+
+               ret = ioctl(fd, GPIO_GET_LINEINFO_IOCTL, &linfo);
+               if (ret == -1) {
+                       ret = -errno;
+                       perror("Failed to issue LINEINFO IOCTL\n");
+                       goto exit_close_error;
+               }
+               fprintf(stdout, "\tline %d:", linfo.line_offset);
+               if (linfo.name[0])
+                       fprintf(stdout, " %s", linfo.name);
+               else
+                       fprintf(stdout, " unnamed");
+               if (linfo.label[0])
+                       fprintf(stdout, " \"%s\"", linfo.label);
+               else
+                       fprintf(stdout, " unlabeled");
+               if (linfo.flags) {
+                       fprintf(stdout, " [");
+                       print_flags(linfo.flags);
+                       fprintf(stdout, "]");
+               }
+               fprintf(stdout, "\n");
+
        }
 
-free_chrdev_name:
+exit_close_error:
+       if (close(fd) == -1)
+               perror("Failed to close GPIO character device file");
        free(chrdev_name);
-
        return ret;
-
 }
 
 void print_usage(void)