| Message ID | 20210427154224.30372-1-a.fatoum@pengutronix.de |
|---|---|
| State | New |
| Headers | show |
| Series | [libgpiod] tools: gpioget: add new --dir-as-is option for GPO read-back | expand |
On Tue, Apr 27, 2021 at 5:42 PM Ahmad Fatoum <a.fatoum@pengutronix.de> wrote: > > Both legacy sysfs and new character device API support querying line > state of a GPIO configured as output. But while sysfs /value can > be read for these output GPIOs, gpioget unconditionally muxes the > line as input. To ease migration to the new user API, add a new > --dir-as-is parameter that doesn't force the line to input. > > This is especially useful for GPIO controllers that maintain their > last configured output state. > > Signed-off-by: Ahmad Fatoum <a.fatoum@pengutronix.de> > --- > -n is chosen for the short option because it's the customary short > option for dry runs, which sounds similar to what a gpio get without > line state configuration is doing. > --- > tools/gpioget.c | 10 ++++++++-- > 1 file changed, 8 insertions(+), 2 deletions(-) > > diff --git a/tools/gpioget.c b/tools/gpioget.c > index ceeec566683a..bfbf5ea748be 100644 > --- a/tools/gpioget.c > +++ b/tools/gpioget.c > @@ -13,11 +13,12 @@ static const struct option longopts[] = { > { "help", no_argument, NULL, 'h' }, > { "version", no_argument, NULL, 'v' }, > { "active-low", no_argument, NULL, 'l' }, > + { "dir-as-is", no_argument, NULL, 'n' }, > { "bias", required_argument, NULL, 'B' }, > { GETOPT_NULL_LONGOPT }, > }; > > -static const char *const shortopts = "+hvlB:"; > +static const char *const shortopts = "+hvlnB:"; > > static void print_help(void) > { > @@ -30,6 +31,7 @@ static void print_help(void) > printf(" -h, --help:\t\tdisplay this message and exit\n"); > printf(" -v, --version:\tdisplay the version and exit\n"); > printf(" -l, --active-low:\tset the line active state to low\n"); > + printf(" -n, --dir-as-is:\tdon't force-reconfigure line direction\n"); > printf(" -B, --bias=[as-is|disable|pull-down|pull-up] (defaults to 'as-is'):\n"); > printf(" set the line bias\n"); > printf("\n"); > @@ -40,6 +42,7 @@ int main(int argc, char **argv) > { > struct gpiod_line_request_config config; > int *values, optc, opti, rv, flags = 0; > + int request_type = GPIOD_LINE_REQUEST_DIRECTION_INPUT; > unsigned int *offsets, i, num_lines; > struct gpiod_line_bulk *lines; > struct gpiod_chip *chip; > @@ -60,6 +63,9 @@ int main(int argc, char **argv) > case 'l': > flags |= GPIOD_LINE_REQUEST_FLAG_ACTIVE_LOW; > break; > + case 'n': > + request_type = GPIOD_LINE_REQUEST_DIRECTION_AS_IS; > + break; > case 'B': > flags |= bias_flags(optarg); > break; > @@ -104,7 +110,7 @@ int main(int argc, char **argv) > memset(&config, 0, sizeof(config)); > > config.consumer = "gpioget"; > - config.request_type = GPIOD_LINE_REQUEST_DIRECTION_INPUT; > + config.request_type = request_type; > config.flags = flags; > > rv = gpiod_line_request_bulk(lines, &config, NULL); > -- > 2.29.2 > Makes sense, applied to master. It'll take some time until this is released though, libgpiod v2 is in the making and I no longer add new features to the v1.6.x branch anymore. Thanks! Bartosz
diff --git a/tools/gpioget.c b/tools/gpioget.c index ceeec566683a..bfbf5ea748be 100644 --- a/tools/gpioget.c +++ b/tools/gpioget.c @@ -13,11 +13,12 @@ static const struct option longopts[] = { { "help", no_argument, NULL, 'h' }, { "version", no_argument, NULL, 'v' }, { "active-low", no_argument, NULL, 'l' }, + { "dir-as-is", no_argument, NULL, 'n' }, { "bias", required_argument, NULL, 'B' }, { GETOPT_NULL_LONGOPT }, }; -static const char *const shortopts = "+hvlB:"; +static const char *const shortopts = "+hvlnB:"; static void print_help(void) { @@ -30,6 +31,7 @@ static void print_help(void) printf(" -h, --help:\t\tdisplay this message and exit\n"); printf(" -v, --version:\tdisplay the version and exit\n"); printf(" -l, --active-low:\tset the line active state to low\n"); + printf(" -n, --dir-as-is:\tdon't force-reconfigure line direction\n"); printf(" -B, --bias=[as-is|disable|pull-down|pull-up] (defaults to 'as-is'):\n"); printf(" set the line bias\n"); printf("\n"); @@ -40,6 +42,7 @@ int main(int argc, char **argv) { struct gpiod_line_request_config config; int *values, optc, opti, rv, flags = 0; + int request_type = GPIOD_LINE_REQUEST_DIRECTION_INPUT; unsigned int *offsets, i, num_lines; struct gpiod_line_bulk *lines; struct gpiod_chip *chip; @@ -60,6 +63,9 @@ int main(int argc, char **argv) case 'l': flags |= GPIOD_LINE_REQUEST_FLAG_ACTIVE_LOW; break; + case 'n': + request_type = GPIOD_LINE_REQUEST_DIRECTION_AS_IS; + break; case 'B': flags |= bias_flags(optarg); break; @@ -104,7 +110,7 @@ int main(int argc, char **argv) memset(&config, 0, sizeof(config)); config.consumer = "gpioget"; - config.request_type = GPIOD_LINE_REQUEST_DIRECTION_INPUT; + config.request_type = request_type; config.flags = flags; rv = gpiod_line_request_bulk(lines, &config, NULL);
Both legacy sysfs and new character device API support querying line state of a GPIO configured as output. But while sysfs /value can be read for these output GPIOs, gpioget unconditionally muxes the line as input. To ease migration to the new user API, add a new --dir-as-is parameter that doesn't force the line to input. This is especially useful for GPIO controllers that maintain their last configured output state. Signed-off-by: Ahmad Fatoum <a.fatoum@pengutronix.de> --- -n is chosen for the short option because it's the customary short option for dry runs, which sounds similar to what a gpio get without line state configuration is doing. --- tools/gpioget.c | 10 ++++++++-- 1 file changed, 8 insertions(+), 2 deletions(-)