[PATCH 22/22] tools: gpio: support monitoring multiple lines

[Kent Gibson]

Extend gpio-event-mon to support monitoring multiple lines.
This would require multiple lineevent requests to implement using uAPI V1,
but can be performed with a single line request using uAPI V2.

Signed-off-by: Kent Gibson <warthog618@xxxxxxxxx>

---
 tools/gpio/gpio-event-mon.c | 41 ++++++++++++++++++++++++++++---------
 1 file changed, 31 insertions(+), 10 deletions(-)

diff --git a/tools/gpio/gpio-event-mon.c b/tools/gpio/gpio-event-mon.c
index ec90e44389dc..ed1adb8247c6 100644
--- a/tools/gpio/gpio-event-mon.c
+++ b/tools/gpio/gpio-event-mon.c
@@ -26,7 +26,8 @@
 #include "gpio-utils.h"
 
 int monitor_device(const char *device_name,
-		   unsigned int line,
+		   unsigned int *lines,
+		   unsigned int num_lines,
 		   struct gpioline_config *config,
 		   unsigned int loops)
 {
@@ -47,7 +48,7 @@ int monitor_device(const char *device_name,
 		goto exit_free_name;
 	}
 
-	ret = gpiotools_request_line(device_name, &line, 1, config,
+	ret = gpiotools_request_line(device_name, lines, num_lines, config,
 				     "gpio-event-mon");
 	if (ret < 0)
 		goto exit_device_close;
@@ -63,9 +64,23 @@ int monitor_device(const char *device_name,
 		goto exit_line_close;
 	}
 
-	fprintf(stdout, "Monitoring line %d on %s\n", line, device_name);
-	fprintf(stdout, "Initial line value: %d\n",
-		gpiotools_test_bit(values.bitmap, 0));
+	if (num_lines == 1) {
+		fprintf(stdout, "Monitoring line %d on %s\n", lines[0], device_name);
+		fprintf(stdout, "Initial line value: %d\n",
+			gpiotools_test_bit(values.bitmap, 0));
+	} else {
+		fprintf(stdout, "Monitoring lines %d", lines[0]);
+		for (i = 1; i < num_lines - 1; i++)
+			fprintf(stdout, ", %d", lines[i]);
+		fprintf(stdout, " and %d on %s\n", lines[i], device_name);
+		fprintf(stdout, "Initial line values: %d",
+			gpiotools_test_bit(values.bitmap, 0));
+		for (i = 1; i < num_lines - 1; i++)
+			fprintf(stdout, ", %d",
+				gpiotools_test_bit(values.bitmap, i));
+		fprintf(stdout, " and %d\n",
+			gpiotools_test_bit(values.bitmap, i));
+	}
 
 	while (1) {
 		struct gpioline_event event;
@@ -124,7 +139,7 @@ void print_usage(void)
 	fprintf(stderr, "Usage: gpio-event-mon [options]...\n"
 		"Listen to events on GPIO lines, 0->1 1->0\n"
 		"  -n <name>  Listen on GPIOs on a named device (must be stated)\n"
-		"  -o <n>     Offset to monitor\n"
+		"  -o <n>     Offset of line to monitor (may be repeated)\n"
 		"  -d         Set line as open drain\n"
 		"  -s         Set line as open source\n"
 		"  -r         Listen for rising edges\n"
@@ -141,7 +156,8 @@ void print_usage(void)
 int main(int argc, char **argv)
 {
 	const char *device_name = NULL;
-	unsigned int line = -1;
+	unsigned int lines[GPIOLINES_MAX];
+	unsigned int num_lines = 0;
 	unsigned int loops = 0;
 	struct gpioline_config config;
 	int c;
@@ -158,7 +174,12 @@ int main(int argc, char **argv)
 			device_name = optarg;
 			break;
 		case 'o':
-			line = strtoul(optarg, NULL, 10);
+			if (num_lines >= GPIOLINES_MAX) {
+				print_usage();
+				return -1;
+			}
+			lines[num_lines] = strtoul(optarg, NULL, 10);
+			num_lines++;
 			break;
 		case 'b':
 			config.flags |= GPIOLINE_FLAG_V2_DEBOUNCE;
@@ -184,7 +205,7 @@ int main(int argc, char **argv)
 		}
 	}
 
-	if (!device_name || line == -1) {
+	if (!device_name || num_lines == 0) {
 		print_usage();
 		return -1;
 	}
@@ -193,5 +214,5 @@ int main(int argc, char **argv)
 		       "falling edges\n");
 		config.edge_detection = GPIOLINE_EDGE_BOTH;
 	}
-	return monitor_device(device_name, line, &config, loops);
+	return monitor_device(device_name, lines, num_lines, &config, loops);
 }
-- 
2.27.0