Some Sitronix LCD controllers (such as the ST7567) don't have a reset pin,
so lets relax this in the driver and make the reset GPIO to be optional.
The devm_gpiod_get_optional() helper is similar to devm_gpiod_get(), but
returns NULL when there isn't a reset-gpios property defined in a DT node.
The DT binding schema for "sitronix,st7571" that require a reset GPIO will
enforce the "reset-gpios" to be present, due being a required DT property.
But in the driver itself the property can be made optional if not defined.
Signed-off-by: Javier Martinez Canillas <javi...@redhat.com>
---
drivers/gpu/drm/sitronix/st7571-i2c.c | 8 ++++++--
1 file changed, 6 insertions(+), 2 deletions(-)
diff --git a/drivers/gpu/drm/sitronix/st7571-i2c.c
b/drivers/gpu/drm/sitronix/st7571-i2c.c
index eec846892962..73e8db25f895 100644
--- a/drivers/gpu/drm/sitronix/st7571-i2c.c
+++ b/drivers/gpu/drm/sitronix/st7571-i2c.c
@@ -802,15 +802,19 @@ static int st7571_parse_dt(struct st7571_device *st7571)
st7571->nlines = dt.vactive.typ;
st7571->ncols = dt.hactive.typ;
- st7571->reset = devm_gpiod_get(dev, "reset", GPIOD_OUT_HIGH);
+ st7571->reset = devm_gpiod_get_optional(dev, "reset", GPIOD_OUT_HIGH);
if (IS_ERR(st7571->reset))
- return PTR_ERR(st7571->reset);
+ return dev_err_probe(dev, PTR_ERR(st7571->reset),
+ "Failed to get reset gpio\n");
return 0;
}
static void st7571_reset(struct st7571_device *st7571)
{
+ if (!st7571->reset)
+ return;
+
gpiod_set_value_cansleep(st7571->reset, 1);
fsleep(20);
gpiod_set_value_cansleep(st7571->reset, 0);
--
2.49.0
