[PATCH 1/2] drm/bridge: sii902x: Provide data-lines property to input endpoint

[Wadim Egorov <w.egorov@phytec.de>]

Introduce a data-lines property to define the number of parallel RGB
input pins connected to the transmitter. The input bus formats are updated
accordingly. If the property is not specified, default to 24 data lines.

Signed-off-by: Wadim Egorov <w.egorov@phytec.de>
---
 drivers/gpu/drm/bridge/sii902x.c | 27 ++++++++++++++++++++++++++-
 1 file changed, 26 insertions(+), 1 deletion(-)

diff --git a/drivers/gpu/drm/bridge/sii902x.c b/drivers/gpu/drm/bridge/sii902x.c
index 7f91b0db161e..3565c3533597 100644
--- a/drivers/gpu/drm/bridge/sii902x.c
+++ b/drivers/gpu/drm/bridge/sii902x.c
@@ -180,6 +180,8 @@ struct sii902x {
 	struct gpio_desc *reset_gpio;
 	struct i2c_mux_core *i2cmux;
 	bool sink_is_hdmi;
+	u32 pd_lines; /* number of Parallel Port Input Data Lines */
+
 	/*
 	 * Mutex protects audio and video functions from interfering
 	 * each other, by keeping their i2c command sequences atomic.
@@ -477,6 +479,8 @@ static u32 *sii902x_bridge_atomic_get_input_bus_fmts(struct drm_bridge *bridge,
 						     u32 output_fmt,
 						     unsigned int *num_input_fmts)
 {
+
+	struct sii902x *sii902x = bridge_to_sii902x(bridge);
 	u32 *input_fmts;
 
 	*num_input_fmts = 0;
@@ -485,7 +489,19 @@ static u32 *sii902x_bridge_atomic_get_input_bus_fmts(struct drm_bridge *bridge,
 	if (!input_fmts)
 		return NULL;
 
-	input_fmts[0] = MEDIA_BUS_FMT_RGB888_1X24;
+	switch (sii902x->pd_lines) {
+	case 16:
+		input_fmts[0] = MEDIA_BUS_FMT_RGB565_1X16;
+		break;
+	case 18:
+		input_fmts[0] = MEDIA_BUS_FMT_RGB666_1X18;
+		break;
+	default:
+	case 24:
+		input_fmts[0] = MEDIA_BUS_FMT_RGB888_1X24;
+		break;
+	}
+
 	*num_input_fmts = 1;
 
 	return input_fmts;
@@ -1167,6 +1183,15 @@ static int sii902x_probe(struct i2c_client *client)
 		return PTR_ERR(sii902x->reset_gpio);
 	}
 
+	endpoint = of_graph_get_endpoint_by_regs(dev->of_node, 0, -1);
+	if (endpoint) {
+		ret = of_property_read_u32(endpoint, "data-lines", &sii902x->pd_lines);
+		if (ret) {
+			dev_dbg(dev, "Could not get data-lines, fallback to 24 data-lines\n");
+			sii902x->pd_lines = 24;
+		}
+	}
+
 	endpoint = of_graph_get_endpoint_by_regs(dev->of_node, 1, -1);
 	if (endpoint) {
 		struct device_node *remote = of_graph_get_remote_port_parent(endpoint);
-- 
2.34.1