[PATCH 09/10] drm/panel: raspberrypi-touchscreen: Use the attach hook

Maxime Ripard
2021-07-20T13:56:04Z

Now that we have an attach hook available for panels as well, let's use
it for the RaspberryPi 7" DSI panel.

This now mimics what all the other bridges in a similar situation are
doing, and we avoid our probe order issue entirely.

Signed-off-by: Maxime Ripard <maxime@cerno.tech>
---
.../drm/panel/panel-raspberrypi-touchscreen.c | 135 ++++++++++--------
1 file changed, 77 insertions(+), 58 deletions(-)

diff --git a/drivers/gpu/drm/panel/panel-raspberrypi-touchscreen.c b/drivers/gpu/drm/panel/panel-raspberrypi-touchscreen.c
index 462faae0f446..995c5cafb970 100644
--- a/drivers/gpu/drm/panel/panel-raspberrypi-touchscreen.c
+++ b/drivers/gpu/drm/panel/panel-raspberrypi-touchscreen.c
@@ -346,7 +346,83 @@ static int rpi_touchscreen_get_modes(struct drm_panel *panel,
return num;
}

+static int rpi_touchscreen_attach(struct drm_panel *panel)
+{
+ struct rpi_touchscreen *ts = panel_to_ts(panel);
+ struct device *dev = &ts->i2c->dev;
+ struct device_node *endpoint, *dsi_host_node;
+ struct mipi_dsi_device *dsi;
+ struct mipi_dsi_host *host;
+ int ret;
+
+ struct mipi_dsi_device_info info = {
+ .type = RPI_DSI_DRIVER_NAME,
+ .channel = 0,
+ .node = NULL,
+ };
+
+ /* Look up the DSI host. It needs to probe before we do. */
+ endpoint = of_graph_get_next_endpoint(dev->of_node, NULL);
+ if (!endpoint)
+ return -ENODEV;
+
+ dsi_host_node = of_graph_get_remote_port_parent(endpoint);
+ if (!dsi_host_node) {
+ of_node_put(endpoint);
+ return -ENODEV;
+ }
+
+ host = of_find_mipi_dsi_host_by_node(dsi_host_node);
+ of_node_put(dsi_host_node);
+ if (!host) {
+ of_node_put(endpoint);
+ return -EPROBE_DEFER;
+ }
+
+ info.node = of_graph_get_remote_port(endpoint);
+ if (!info.node) {
+ of_node_put(endpoint);
+ return -ENODEV;
+ }
+
+ of_node_put(endpoint);
+
+ dsi = mipi_dsi_device_register_full(host, &info);
+ if (IS_ERR(dsi)) {
+ dev_err(dev, "DSI device registration failed: %ld\n",
+ PTR_ERR(dsi));
+ return PTR_ERR(dsi);
+ }
+
+ ts->dsi = dsi;
+
+ dsi->mode_flags = (MIPI_DSI_MODE_VIDEO |
+ MIPI_DSI_MODE_VIDEO_SYNC_PULSE |
+ MIPI_DSI_MODE_LPM);
+ dsi->format = MIPI_DSI_FMT_RGB888;
+ dsi->lanes = 1;
+
+ ret = mipi_dsi_attach(dsi);
+ if (ret) {
+ dev_err(&dsi->dev, "failed to attach dsi to host: %d\n", ret);
+ return ret;
+ }
+
+ return 0;
+}
+
+static void rpi_touchscreen_detach(struct drm_panel *panel)
+{
+ struct rpi_touchscreen *ts = panel_to_ts(panel);
+
+ mipi_dsi_detach(ts->dsi);
+ mipi_dsi_device_unregister(ts->dsi);
+}
+
static const struct drm_panel_funcs rpi_touchscreen_funcs = {
+ .attach = rpi_touchscreen_attach,
+ .detach = rpi_touchscreen_detach,
+
.disable = rpi_touchscreen_disable,
.unprepare = rpi_touchscreen_noop,
.prepare = rpi_touchscreen_noop,
@@ -359,14 +435,7 @@ static int rpi_touchscreen_probe(struct i2c_client *i2c,
{
struct device *dev = &i2c->dev;
struct rpi_touchscreen *ts;
- struct device_node *endpoint, *dsi_host_node;
- struct mipi_dsi_host *host;
int ver;
- struct mipi_dsi_device_info info = {
- .type = RPI_DSI_DRIVER_NAME,
- .channel = 0,
- .node = NULL,
- };

ts = devm_kzalloc(dev, sizeof(*ts), GFP_KERNEL);
if (!ts)
@@ -394,35 +463,6 @@ static int rpi_touchscreen_probe(struct i2c_client *i2c,
/* /\* Turn off at boot, so we can cleanly sequence powering on. *\/ */
/* rpi_touchscreen_i2c_write(ts, REG_POWERON, 0); */

- /* Look up the DSI host. It needs to probe before we do. */
- endpoint = of_graph_get_next_endpoint(dev->of_node, NULL);
- if (!endpoint)
- return -ENODEV;
-
- dsi_host_node = of_graph_get_remote_port_parent(endpoint);
- if (!dsi_host_node)
- goto error;
-
- host = of_find_mipi_dsi_host_by_node(dsi_host_node);
- of_node_put(dsi_host_node);
- if (!host) {
- of_node_put(endpoint);
- return -EPROBE_DEFER;
- }
-
- info.node = of_graph_get_remote_port(endpoint);
- if (!info.node)
- goto error;
-
- of_node_put(endpoint);
-
- ts->dsi = mipi_dsi_device_register_full(host, &info);
- if (IS_ERR(ts->dsi)) {
- dev_err(dev, "DSI device registration failed: %ld\n",
- PTR_ERR(ts->dsi));
- return PTR_ERR(ts->dsi);
- }
-
drm_panel_init(&ts->base, dev, &rpi_touchscreen_funcs,
DRM_MODE_CONNECTOR_DSI);

@@ -432,41 +472,20 @@ static int rpi_touchscreen_probe(struct i2c_client *i2c,
drm_panel_add(&ts->base);

return 0;
-
-error:
- of_node_put(endpoint);
- return -ENODEV;
}

static int rpi_touchscreen_remove(struct i2c_client *i2c)
{
struct rpi_touchscreen *ts = i2c_get_clientdata(i2c);

- mipi_dsi_detach(ts->dsi);
-
drm_panel_remove(&ts->base);

- mipi_dsi_device_unregister(ts->dsi);
-
return 0;
}

static int rpi_touchscreen_dsi_probe(struct mipi_dsi_device *dsi)
{
- int ret;
-
- dsi->mode_flags = (MIPI_DSI_MODE_VIDEO |
- MIPI_DSI_MODE_VIDEO_SYNC_PULSE |
- MIPI_DSI_MODE_LPM);
- dsi->format = MIPI_DSI_FMT_RGB888;
- dsi->lanes = 1;
-
- ret = mipi_dsi_attach(dsi);
-
- if (ret)
- dev_err(&dsi->dev, "failed to attach dsi to host: %d\n", ret);
-
- return ret;
+ return 0;
}

static struct mipi_dsi_driver rpi_touchscreen_dsi_driver = {
--
2.31.1