Re: [PATCH] drm/bridge: sii902x: add support for DRM_BRIDGE_ATTACH_NO_CONNECTOR

From: Robert Foss
Date: Mon Jan 17 2022 - 04:53:57 EST


Hey Neil,

On Thu, 13 Jan 2022 at 15:43, Neil Armstrong <narmstrong@xxxxxxxxxxxx> wrote:
>
> This adds support for DRM_BRIDGE_ATTACH_NO_CONNECTOR by adding the
> bridge get_edid() and detect() callbacks after refactoring the connector
> get_modes() and connector_detect() callbacks.
>
> In order to keep the bridge working, extra code in get_modes() has been
> moved to more logical places.
>
> Signed-off-by: Neil Armstrong <narmstrong@xxxxxxxxxxxx>
> ---
> drivers/gpu/drm/bridge/sii902x.c | 129 ++++++++++++++++++++++++-------
> 1 file changed, 99 insertions(+), 30 deletions(-)
>
> diff --git a/drivers/gpu/drm/bridge/sii902x.c b/drivers/gpu/drm/bridge/sii902x.c
> index 89558e581530..65549fbfdc87 100644
> --- a/drivers/gpu/drm/bridge/sii902x.c
> +++ b/drivers/gpu/drm/bridge/sii902x.c
> @@ -166,10 +166,12 @@ struct sii902x {
> struct i2c_client *i2c;
> struct regmap *regmap;
> struct drm_bridge bridge;
> + struct drm_bridge *next_bridge;
> struct drm_connector connector;
> struct gpio_desc *reset_gpio;
> struct i2c_mux_core *i2cmux;
> struct regulator_bulk_data supplies[2];
> + bool sink_is_hdmi;
> /*
> * Mutex protects audio and video functions from interfering
> * each other, by keeping their i2c command sequences atomic.
> @@ -245,10 +247,8 @@ static void sii902x_reset(struct sii902x *sii902x)
> gpiod_set_value(sii902x->reset_gpio, 0);
> }
>
> -static enum drm_connector_status
> -sii902x_connector_detect(struct drm_connector *connector, bool force)
> +static enum drm_connector_status sii902x_detect(struct sii902x *sii902x)
> {
> - struct sii902x *sii902x = connector_to_sii902x(connector);
> unsigned int status;
>
> mutex_lock(&sii902x->mutex);
> @@ -261,6 +261,14 @@ sii902x_connector_detect(struct drm_connector *connector, bool force)
> connector_status_connected : connector_status_disconnected;
> }
>
> +static enum drm_connector_status
> +sii902x_connector_detect(struct drm_connector *connector, bool force)
> +{
> + struct sii902x *sii902x = connector_to_sii902x(connector);
> +
> + return sii902x_detect(sii902x);
> +}
> +
> static const struct drm_connector_funcs sii902x_connector_funcs = {
> .detect = sii902x_connector_detect,
> .fill_modes = drm_helper_probe_single_connector_modes,
> @@ -270,42 +278,40 @@ static const struct drm_connector_funcs sii902x_connector_funcs = {
> .atomic_destroy_state = drm_atomic_helper_connector_destroy_state,
> };
>
> -static int sii902x_get_modes(struct drm_connector *connector)
> +static struct edid *sii902x_get_edid(struct sii902x *sii902x,
> + struct drm_connector *connector)
> {
> - struct sii902x *sii902x = connector_to_sii902x(connector);
> - u32 bus_format = MEDIA_BUS_FMT_RGB888_1X24;
> - u8 output_mode = SII902X_SYS_CTRL_OUTPUT_DVI;
> struct edid *edid;
> - int num = 0, ret;
>
> mutex_lock(&sii902x->mutex);
>
> edid = drm_get_edid(connector, sii902x->i2cmux->adapter[0]);
> - drm_connector_update_edid_property(connector, edid);
> if (edid) {
> if (drm_detect_hdmi_monitor(edid))
> - output_mode = SII902X_SYS_CTRL_OUTPUT_HDMI;
> -
> - num = drm_add_edid_modes(connector, edid);
> - kfree(edid);
> + sii902x->sink_is_hdmi = true;
> + else
> + sii902x->sink_is_hdmi = false;
> }
>
> - ret = drm_display_info_set_bus_formats(&connector->display_info,
> - &bus_format, 1);
> - if (ret)
> - goto error_out;
> + mutex_unlock(&sii902x->mutex);
>
> - ret = regmap_update_bits(sii902x->regmap, SII902X_SYS_CTRL_DATA,
> - SII902X_SYS_CTRL_OUTPUT_MODE, output_mode);
> - if (ret)
> - goto error_out;
> + return edid;
> +}
>
> - ret = num;
> +static int sii902x_get_modes(struct drm_connector *connector)
> +{
> + struct sii902x *sii902x = connector_to_sii902x(connector);
> + struct edid *edid;
> + int num = 0;
>
> -error_out:
> - mutex_unlock(&sii902x->mutex);
> + edid = sii902x_get_edid(sii902x, connector);
> + drm_connector_update_edid_property(connector, edid);
> + if (edid) {
> + num = drm_add_edid_modes(connector, edid);
> + kfree(edid);
> + }
>
> - return ret;
> + return num;
> }
>
> static enum drm_mode_status sii902x_mode_valid(struct drm_connector *connector,
> @@ -354,12 +360,16 @@ static void sii902x_bridge_mode_set(struct drm_bridge *bridge,
> const struct drm_display_mode *adj)
> {
> struct sii902x *sii902x = bridge_to_sii902x(bridge);
> + u8 output_mode = SII902X_SYS_CTRL_OUTPUT_DVI;
> struct regmap *regmap = sii902x->regmap;
> u8 buf[HDMI_INFOFRAME_SIZE(AVI)];
> struct hdmi_avi_infoframe frame;
> u16 pixel_clock_10kHz = adj->clock / 10;
> int ret;
>
> + if (sii902x->sink_is_hdmi)
> + output_mode = SII902X_SYS_CTRL_OUTPUT_HDMI;
> +
> buf[0] = pixel_clock_10kHz & 0xff;
> buf[1] = pixel_clock_10kHz >> 8;
> buf[2] = drm_mode_vrefresh(adj);
> @@ -375,6 +385,11 @@ static void sii902x_bridge_mode_set(struct drm_bridge *bridge,
>
> mutex_lock(&sii902x->mutex);
>
> + ret = regmap_update_bits(sii902x->regmap, SII902X_SYS_CTRL_DATA,
> + SII902X_SYS_CTRL_OUTPUT_MODE, output_mode);
> + if (ret)
> + goto out;
> +
> ret = regmap_bulk_write(regmap, SII902X_TPI_VIDEO_DATA, buf, 10);
> if (ret)
> goto out;
> @@ -405,13 +420,13 @@ static int sii902x_bridge_attach(struct drm_bridge *bridge,
> enum drm_bridge_attach_flags flags)
> {
> struct sii902x *sii902x = bridge_to_sii902x(bridge);
> + u32 bus_format = MEDIA_BUS_FMT_RGB888_1X24;
> struct drm_device *drm = bridge->dev;
> int ret;
>
> - if (flags & DRM_BRIDGE_ATTACH_NO_CONNECTOR) {
> - DRM_ERROR("Fix bridge driver to make connector optional!");
> - return -EINVAL;
> - }
> + if (flags & DRM_BRIDGE_ATTACH_NO_CONNECTOR)
> + return drm_bridge_attach(bridge->encoder, sii902x->next_bridge,
> + bridge, flags);
>
> drm_connector_helper_add(&sii902x->connector,
> &sii902x_connector_helper_funcs);
> @@ -433,16 +448,38 @@ static int sii902x_bridge_attach(struct drm_bridge *bridge,
> else
> sii902x->connector.polled = DRM_CONNECTOR_POLL_CONNECT;
>
> + ret = drm_display_info_set_bus_formats(&sii902x->connector.display_info,
> + &bus_format, 1);
> + if (ret)
> + return ret;
> +
> drm_connector_attach_encoder(&sii902x->connector, bridge->encoder);
>
> return 0;
> }
>
> +static enum drm_connector_status sii902x_bridge_detect(struct drm_bridge *bridge)
> +{
> + struct sii902x *sii902x = bridge_to_sii902x(bridge);
> +
> + return sii902x_detect(sii902x);
> +}
> +
> +static struct edid *sii902x_bridge_get_edid(struct drm_bridge *bridge,
> + struct drm_connector *connector)
> +{
> + struct sii902x *sii902x = bridge_to_sii902x(bridge);
> +
> + return sii902x_get_edid(sii902x, connector);
> +}
> +
> static const struct drm_bridge_funcs sii902x_bridge_funcs = {
> .attach = sii902x_bridge_attach,
> .mode_set = sii902x_bridge_mode_set,
> .disable = sii902x_bridge_disable,
> .enable = sii902x_bridge_enable,
> + .detect = sii902x_bridge_detect,
> + .get_edid = sii902x_bridge_get_edid,
> };
>
> static int sii902x_mute(struct sii902x *sii902x, bool mute)
> @@ -829,8 +866,12 @@ static irqreturn_t sii902x_interrupt(int irq, void *data)
>
> mutex_unlock(&sii902x->mutex);
>
> - if ((status & SII902X_HOTPLUG_EVENT) && sii902x->bridge.dev)
> + if ((status & SII902X_HOTPLUG_EVENT) && sii902x->bridge.dev) {
> drm_helper_hpd_irq_event(sii902x->bridge.dev);
> + drm_bridge_hpd_notify(&sii902x->bridge, (status & SII902X_PLUGGED_STATUS)
> + ? connector_status_connected
> + : connector_status_disconnected);
> + }
>
> return IRQ_HANDLED;
> }
> @@ -1001,6 +1042,11 @@ static int sii902x_init(struct sii902x *sii902x)
> sii902x->bridge.funcs = &sii902x_bridge_funcs;
> sii902x->bridge.of_node = dev->of_node;
> sii902x->bridge.timings = &default_sii902x_timings;
> + sii902x->bridge.ops = DRM_BRIDGE_OP_DETECT | DRM_BRIDGE_OP_EDID;
> +
> + if (sii902x->i2c->irq > 0)
> + sii902x->bridge.ops |= DRM_BRIDGE_OP_HPD;
> +
> drm_bridge_add(&sii902x->bridge);
>
> sii902x_audio_codec_init(sii902x, dev);
> @@ -1022,6 +1068,7 @@ static int sii902x_probe(struct i2c_client *client,
> const struct i2c_device_id *id)
> {
> struct device *dev = &client->dev;
> + struct device_node *endpoint;
> struct sii902x *sii902x;
> int ret;
>
> @@ -1049,6 +1096,28 @@ static int sii902x_probe(struct i2c_client *client,
> return PTR_ERR(sii902x->reset_gpio);
> }
>
> + 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);
> +
> + of_node_put(endpoint);
> + if (!remote) {
> + dev_err(dev, "Endpoint in port@1 unconnected\n");
> + return -ENODEV;
> + }
> +
> + if (!of_device_is_available(remote)) {
> + dev_err(dev, "port@1 remote device is disabled\n");
> + of_node_put(remote);
> + return -ENODEV;
> + }
> +
> + sii902x->next_bridge = of_drm_find_bridge(remote);
> + of_node_put(remote);
> + if (!sii902x->next_bridge)
> + return -EPROBE_DEFER;
> + }
> +
> mutex_init(&sii902x->mutex);
>
> sii902x->supplies[0].supply = "iovcc";

Reviewed-by: Robert Foss <robert.foss@xxxxxxxxxx>

Applied to drm-misc-next.