[PATCH v10 19/20] tools: gpio: add multi-line monitoring to gpio-event-mon

From: Kent Gibson
Date: Sun Sep 27 2020 - 20:32:16 EST


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>
Reviewed-by: Andy Shevchenko <andy.shevchenko@xxxxxxxxx>
---
tools/gpio/gpio-event-mon.c | 45 ++++++++++++++++++++++++++++---------
1 file changed, 34 insertions(+), 11 deletions(-)

diff --git a/tools/gpio/gpio-event-mon.c b/tools/gpio/gpio-event-mon.c
index b230af889f26..0c34f18f511c 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 gpio_v2_line_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;
@@ -55,8 +56,10 @@ int monitor_device(const char *device_name,
lfd = ret;

/* Read initial states */
- values.mask = 1;
+ values.mask = 0;
values.bits = 0;
+ for (i = 0; i < num_lines; i++)
+ gpiotools_set_bit(&values.mask, i);
ret = gpiotools_get_values(lfd, &values);
if (ret < 0) {
fprintf(stderr,
@@ -65,9 +68,23 @@ 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.bits, 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.bits, 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.bits, 0));
+ for (i = 1; i < num_lines - 1; i++)
+ fprintf(stdout, ", %d",
+ gpiotools_test_bit(values.bits, i));
+ fprintf(stdout, " and %d\n",
+ gpiotools_test_bit(values.bits, i));
+ }

while (1) {
struct gpio_v2_line_event event;
@@ -126,7 +143,7 @@ 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"
@@ -146,7 +163,8 @@ void print_usage(void)
int main(int argc, char **argv)
{
const char *device_name = NULL;
- unsigned int line = -1;
+ unsigned int lines[GPIO_V2_LINES_MAX];
+ unsigned int num_lines = 0;
unsigned int loops = 0;
struct gpio_v2_line_config config;
int c;
@@ -162,7 +180,12 @@ int main(int argc, char **argv)
device_name = optarg;
break;
case 'o':
- line = strtoul(optarg, NULL, 10);
+ if (num_lines >= GPIO_V2_LINES_MAX) {
+ print_usage();
+ return -1;
+ }
+ lines[num_lines] = strtoul(optarg, NULL, 10);
+ num_lines++;
break;
case 'd':
config.flags |= GPIO_V2_LINE_FLAG_OPEN_DRAIN;
@@ -182,7 +205,7 @@ int main(int argc, char **argv)
}
}

- if (!device_name || line == -1) {
+ if (!device_name || num_lines == 0) {
print_usage();
return -1;
}
@@ -191,5 +214,5 @@ int main(int argc, char **argv)
"falling edges\n");
config.flags |= EDGE_FLAGS;
}
- return monitor_device(device_name, line, &config, loops);
+ return monitor_device(device_name, lines, num_lines, &config, loops);
}
--
2.28.0