Unverified Commit adca62ec authored by Hsin-Yi Wang's avatar Hsin-Yi Wang Committed by Robert Foss
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drm/bridge: anx7625: Support reading edid through aux channel 



Support reading edid through aux channel if panel is connected to aux
bus. Extend anx7625_aux_dpcd_trans() to implement aux transfer function:

1. panel is populated in devm_of_dp_aux_populate_ep_devices(), so move
   anx7625_parse_dt() after.
2. Use pm runtime autosuspend since aux transfer function is called
   multiple times when reading edid.
3. No-op if aux transfer length is 0.

Signed-off-by: default avatarHsin-Yi Wang <hsinyi@chromium.org>
Reviewed-by: default avatarXin Ji <xji@analogixsemi.com>
Reported-by: default avatarkernel test robot <lkp@intel.com>
Signed-off-by: default avatarRobert Foss <robert.foss@linaro.org>
Link: https://patchwork.freedesktop.org/patch/msgid/20220213103437.3363848-3-hsinyi@chromium.org
parent 57bfb34a

drivers/gpu/drm/bridge/analogix/Kconfig

+2 −0
Original line number Diff line number Diff line
@@ -32,6 +32,8 @@ config DRM_ANALOGIX_ANX7625 
	tristate "Analogix Anx7625 MIPI to DP interface support"

	depends on DRM

	depends on OF

	select DRM_DP_AUX_BUS

	select DRM_DP_HELPER

	select DRM_MIPI_DSI

	help

	  ANX7625 is an ultra-low power 4K mobile HD transmitter

drivers/gpu/drm/bridge/analogix/anx7625.c

+102 −18
Original line number Diff line number Diff line
@@ -24,6 +24,7 @@ 
#include <drm/drm_atomic_helper.h>

#include <drm/drm_bridge.h>

#include <drm/drm_crtc_helper.h>

#include <drm/dp/drm_dp_aux_bus.h>

#include <drm/dp/drm_dp_helper.h>

#include <drm/drm_edid.h>

#include <drm/drm_hdcp.h>
@@ -231,19 +232,23 @@ static int wait_aux_op_finish(struct anx7625_data *ctx) 
	return 0;

}



static int anx7625_aux_dpcd_trans(struct anx7625_data *ctx, u8 op,

				  u32 address, u8 len, u8 *buf)

static int anx7625_aux_trans(struct anx7625_data *ctx, u8 op, u32 address,

			     u8 len, u8 *buf)

{

	struct device *dev = &ctx->client->dev;

	int ret;

	u8 addrh, addrm, addrl;

	u8 cmd;

	bool is_write = !(op & DP_AUX_I2C_READ);



	if (len > MAX_DPCD_BUFFER_SIZE) {

	if (len > DP_AUX_MAX_PAYLOAD_BYTES) {

		dev_err(dev, "exceed aux buffer len.\n");

		return -EINVAL;

	}



	if (!len)

		return len;



	addrl = address & 0xFF;

	addrm = (address >> 8) & 0xFF;

	addrh = (address >> 16) & 0xFF;
@@ -262,7 +267,7 @@ static int anx7625_aux_dpcd_trans(struct anx7625_data *ctx, u8 op, 
	ret |= anx7625_reg_write(ctx, ctx->i2c.rx_p0_client,

				 AP_AUX_ADDR_19_16, addrh);



	if (op == DP_AUX_NATIVE_WRITE)

	if (is_write)

		ret |= anx7625_reg_block_write(ctx, ctx->i2c.rx_p0_client,

					       AP_AUX_BUFF_START, len, buf);

	/* Enable aux access */
@@ -275,14 +280,14 @@ static int anx7625_aux_dpcd_trans(struct anx7625_data *ctx, u8 op, 
	}



	ret = wait_aux_op_finish(ctx);

	if (ret) {

	if (ret < 0) {

		dev_err(dev, "aux IO error: wait aux op finish.\n");

		return ret;

	}



	/* Write done */

	if (op == DP_AUX_NATIVE_WRITE)

		return 0;

	if (is_write)

		return len;



	/* Read done, read out dpcd data */

	ret = anx7625_reg_block_read(ctx, ctx->i2c.rx_p0_client,
@@ -292,7 +297,7 @@ static int anx7625_aux_dpcd_trans(struct anx7625_data *ctx, u8 op, 
		return -EIO;

	}



	return 0;

	return len;

}



static int anx7625_video_mute_control(struct anx7625_data *ctx,
@@ -867,7 +872,7 @@ static int anx7625_hdcp_enable(struct anx7625_data *ctx) 
	}



	/* Read downstream capability */

	anx7625_aux_dpcd_trans(ctx, DP_AUX_NATIVE_READ, 0x68028, 1, &bcap);

	anx7625_aux_trans(ctx, DP_AUX_NATIVE_READ, 0x68028, 1, &bcap);

	if (!(bcap & 0x01)) {

		pr_warn("downstream not support HDCP 1.4, cap(%x).\n", bcap);

		return 0;
@@ -956,7 +961,7 @@ static void anx7625_dp_stop(struct anx7625_data *ctx) 
	dev_dbg(dev, "notify downstream enter into standby\n");

	/* Downstream monitor enter into standby mode */

	data = 2;

	ret |= anx7625_aux_dpcd_trans(ctx, DP_AUX_NATIVE_WRITE, 0x000600, 1, &data);

	ret |= anx7625_aux_trans(ctx, DP_AUX_NATIVE_WRITE, 0x000600, 1, &data);

	if (ret < 0)

		DRM_DEV_ERROR(dev, "IO error : mute video fail\n");
@@ -1655,11 +1660,56 @@ static int anx7625_parse_dt(struct device *dev, 
	return 0;

}



static bool anx7625_of_panel_on_aux_bus(struct device *dev)

{

	struct device_node *bus, *panel;



	bus = of_get_child_by_name(dev->of_node, "aux-bus");

	if (!bus)

		return false;



	panel = of_get_child_by_name(bus, "panel");

	of_node_put(bus);

	if (!panel)

		return false;

	of_node_put(panel);



	return true;

}



static inline struct anx7625_data *bridge_to_anx7625(struct drm_bridge *bridge)

{

	return container_of(bridge, struct anx7625_data, bridge);

}



static ssize_t anx7625_aux_transfer(struct drm_dp_aux *aux,

				    struct drm_dp_aux_msg *msg)

{

	struct anx7625_data *ctx = container_of(aux, struct anx7625_data, aux);

	struct device *dev = &ctx->client->dev;

	u8 request = msg->request & ~DP_AUX_I2C_MOT;

	int ret = 0;



	pm_runtime_get_sync(dev);

	msg->reply = 0;

	switch (request) {

	case DP_AUX_NATIVE_WRITE:

	case DP_AUX_I2C_WRITE:

	case DP_AUX_NATIVE_READ:

	case DP_AUX_I2C_READ:

		break;

	default:

		ret = -EINVAL;

	}

	if (!ret)

		ret = anx7625_aux_trans(ctx, msg->request, msg->address,

					msg->size, msg->buffer);

	pm_runtime_mark_last_busy(dev);

	pm_runtime_put_autosuspend(dev);



	return ret;

}



static struct edid *anx7625_get_edid(struct anx7625_data *ctx)

{

	struct device *dev = &ctx->client->dev;
@@ -2066,6 +2116,13 @@ static int anx7625_bridge_attach(struct drm_bridge *bridge, 
		return -ENODEV;

	}



	ctx->aux.drm_dev = bridge->dev;

	err = drm_dp_aux_register(&ctx->aux);

	if (err) {

		dev_err(dev, "failed to register aux channel: %d\n", err);

		return err;

	}



	if (ctx->pdata.panel_bridge) {

		err = drm_bridge_attach(bridge->encoder,

					ctx->pdata.panel_bridge,
@@ -2079,6 +2136,13 @@ static int anx7625_bridge_attach(struct drm_bridge *bridge, 
	return 0;

}



static void anx7625_bridge_detach(struct drm_bridge *bridge)

{

	struct anx7625_data *ctx = bridge_to_anx7625(bridge);



	drm_dp_aux_unregister(&ctx->aux);

}



static enum drm_mode_status

anx7625_bridge_mode_valid(struct drm_bridge *bridge,

			  const struct drm_display_info *info,
@@ -2344,6 +2408,7 @@ static struct edid *anx7625_bridge_get_edid(struct drm_bridge *bridge, 


static const struct drm_bridge_funcs anx7625_bridge_funcs = {

	.attach = anx7625_bridge_attach,

	.detach = anx7625_bridge_detach,

	.mode_valid = anx7625_bridge_mode_valid,

	.mode_set = anx7625_bridge_mode_set,

	.atomic_check = anx7625_bridge_atomic_check,
@@ -2501,6 +2566,12 @@ static const struct dev_pm_ops anx7625_pm_ops = { 
			   anx7625_runtime_pm_resume, NULL)

};



static void anx7625_runtime_disable(void *data)

{

	pm_runtime_dont_use_autosuspend(data);

	pm_runtime_disable(data);

}



static int anx7625_i2c_probe(struct i2c_client *client,

			     const struct i2c_device_id *id)

{
@@ -2523,13 +2594,6 @@ static int anx7625_i2c_probe(struct i2c_client *client, 


	pdata = &platform->pdata;



	ret = anx7625_parse_dt(dev, pdata);

	if (ret) {

		if (ret != -EPROBE_DEFER)

			DRM_DEV_ERROR(dev, "fail to parse DT : %d\n", ret);

		return ret;

	}



	platform->client = client;

	i2c_set_clientdata(client, platform);
@@ -2577,6 +2641,19 @@ static int anx7625_i2c_probe(struct i2c_client *client, 
		}

	}



	platform->aux.name = "anx7625-aux";

	platform->aux.dev = dev;

	platform->aux.transfer = anx7625_aux_transfer;

	drm_dp_aux_init(&platform->aux);

	devm_of_dp_aux_populate_ep_devices(&platform->aux);



	ret = anx7625_parse_dt(dev, pdata);

	if (ret) {

		if (ret != -EPROBE_DEFER)

			DRM_DEV_ERROR(dev, "fail to parse DT : %d\n", ret);

		return ret;

	}



	if (anx7625_register_i2c_dummy_clients(platform, client) != 0) {

		ret = -ENOMEM;

		DRM_DEV_ERROR(dev, "fail to reserve I2C bus.\n");
@@ -2584,6 +2661,12 @@ static int anx7625_i2c_probe(struct i2c_client *client, 
	}



	pm_runtime_enable(dev);

	pm_runtime_set_autosuspend_delay(dev, 1000);

	pm_runtime_use_autosuspend(dev);

	pm_suspend_ignore_children(dev, true);

	ret = devm_add_action_or_reset(dev, anx7625_runtime_disable, dev);

	if (ret)

		return ret;



	if (!platform->pdata.low_power_mode) {

		anx7625_disable_pd_protocol(platform);
@@ -2596,7 +2679,8 @@ static int anx7625_i2c_probe(struct i2c_client *client, 


	platform->bridge.funcs = &anx7625_bridge_funcs;

	platform->bridge.of_node = client->dev.of_node;

	platform->bridge.ops = DRM_BRIDGE_OP_EDID;

	if (!anx7625_of_panel_on_aux_bus(&client->dev))

		platform->bridge.ops |= DRM_BRIDGE_OP_EDID;

	if (!platform->pdata.panel_bridge)

		platform->bridge.ops |= DRM_BRIDGE_OP_HPD |

					DRM_BRIDGE_OP_DETECT;

drivers/gpu/drm/bridge/analogix/anx7625.h

+1 −0
Original line number Diff line number Diff line
@@ -472,6 +472,7 @@ struct anx7625_data { 
	u8 bridge_attached;

	struct drm_connector *connector;

	struct mipi_dsi_device *dsi;

	struct drm_dp_aux aux;

};



#endif  /* __ANX7625_H__ */