Re: [PATCH] drm/bridge: sii902x: add support for DRM_BRIDGE_ATTACH_NO_CONNECTOR
From: Dmitry Osipenko
Date: Sun Aug 14 2022 - 20:18:28 EST
08.08.2022 12:15, Neil Armstrong пишет:
> Hi Dmitry,
>
> On 31/07/2022 22:07, Dmitry Osipenko wrote:
>> 13.01.2022 17:43, Neil Armstrong пишет:
>>> 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;
>>
>> Hi,
>>
>> This patch broke ARM/QEMU vexpress display because of_drm_find_bridge()
>> always fail with -EPROBE_DEFER. Reverting this patch returns display
>> back. Please fix or revert, thanks in advance.
>
> Can you share a QEMU cmdline to reproduce ?
qemu-system-arm -cpu cortex-a9 -M vexpress-a9 -smp 2 -m 1024 -kernel
arch/arm/boot/zImage -dtb arch/arm/boot/dts/vexpress-v2p-ca9.dtb -serial
stdio -net nic,model=lan9118 -net user