@@ -186,6 +186,28 @@ static int vx855gpio_direction_output(struct gpio_chip *gpio,
return 0;
}
+static int vx855gpio_set_single_ended(struct gpio_chip *gpio,
+ unsigned int nr,
+ enum single_ended_mode mode)
+{
+ /* The GPI cannot be single-ended */
+ if (nr < NR_VX855_GPI)
+ return -EINVAL;
+
+ /* The GPO's are push-pull */
+ if (nr < NR_VX855_GPInO) {
+ if (mode != LINE_MODE_PUSH_PULL)
+ return -ENOTSUPP;
+ return 0;
+ }
+
+ /* The GPIO's are open drain */
+ if (mode != LINE_MODE_OPEN_DRAIN)
+ return -ENOTSUPP;
+
+ return 0;
+}
+
static const char *vx855gpio_names[NR_VX855_GP] = {
"VX855_GPI0", "VX855_GPI1", "VX855_GPI2", "VX855_GPI3", "VX855_GPI4",
"VX855_GPI5", "VX855_GPI6", "VX855_GPI7", "VX855_GPI8", "VX855_GPI9",
@@ -209,6 +231,7 @@ static void vx855gpio_gpio_setup(struct vx855_gpio *vg)
c->direction_output = vx855gpio_direction_output;
c->get = vx855gpio_get;
c->set = vx855gpio_set;
+ c->set_single_ended = vx855gpio_set_single_ended;
c->dbg_show = NULL;
c->base = 0;
c->ngpio = NR_VX855_GP;
The vx855 driver clearly states it has three groups of lines: GPI, GPO and GPIO. The GPO are assumedly push-pull. The GPIO are implicit open drain, but if the GPIO subsystem ask for them to be explicitly open drain (i.e. set the flag on a machine table that we want open drain) it will currently misbehave: it will switch the GPIOs to input mode (emulate open drain). Instead: indicate in the .set_single_ended() callback that we support open drain and open drain only. Cc: Daniel Drake <drake@endlessm.com> Signed-off-by: Linus Walleij <linus.walleij@linaro.org> --- drivers/gpio/gpio-vx855.c | 23 +++++++++++++++++++++++ 1 file changed, 23 insertions(+)