2022-01-11 06:31:32

by Xin Ji

[permalink] [raw]
Subject: [PATCH v2 1/1] drm/bridge: anx7625: send DPCD command to downstream

Send DPCD command to downstream before anx7625 power down,
let downstream monitor enter into standby mode.

Signed-off-by: Xin Ji <[email protected]>
---
drivers/gpu/drm/bridge/analogix/anx7625.c | 40 ++++++++++++++++++++---
1 file changed, 35 insertions(+), 5 deletions(-)

diff --git a/drivers/gpu/drm/bridge/analogix/anx7625.c b/drivers/gpu/drm/bridge/analogix/anx7625.c
index 33383f83255d..fd2217ae455e 100644
--- a/drivers/gpu/drm/bridge/analogix/anx7625.c
+++ b/drivers/gpu/drm/bridge/analogix/anx7625.c
@@ -129,6 +129,23 @@ static int anx7625_reg_write(struct anx7625_data *ctx,
return ret;
}

+static int anx7625_reg_block_write(struct anx7625_data *ctx,
+ struct i2c_client *client,
+ u8 reg_addr, u8 len, u8 *buf)
+{
+ int ret;
+ struct device *dev = &client->dev;
+
+ i2c_access_workaround(ctx, client);
+
+ ret = i2c_smbus_write_i2c_block_data(client, reg_addr, len, buf);
+ if (ret < 0)
+ DRM_DEV_ERROR(dev, "write i2c block failed id=%x\n:%x",
+ client->addr, reg_addr);
+
+ return ret;
+}
+
static int anx7625_write_or(struct anx7625_data *ctx,
struct i2c_client *client,
u8 offset, u8 mask)
@@ -214,8 +231,8 @@ static int wait_aux_op_finish(struct anx7625_data *ctx)
return 0;
}

-static int anx7625_aux_dpcd_read(struct anx7625_data *ctx,
- u32 address, u8 len, u8 *buf)
+static int anx7625_aux_dpcd_trans(struct anx7625_data *ctx, u8 op,
+ u32 address, u8 len, u8 *buf)
{
struct device *dev = &ctx->client->dev;
int ret;
@@ -231,8 +248,7 @@ static int anx7625_aux_dpcd_read(struct anx7625_data *ctx,
addrm = (address >> 8) & 0xFF;
addrh = (address >> 16) & 0xFF;

- cmd = DPCD_CMD(len, DPCD_READ);
- cmd = ((len - 1) << 4) | 0x09;
+ cmd = DPCD_CMD(len, op);

/* Set command and length */
ret = anx7625_reg_write(ctx, ctx->i2c.rx_p0_client,
@@ -246,6 +262,9 @@ static int anx7625_aux_dpcd_read(struct anx7625_data *ctx,
ret |= anx7625_reg_write(ctx, ctx->i2c.rx_p0_client,
AP_AUX_ADDR_19_16, addrh);

+ if (op == DPCD_WRITE)
+ ret |= anx7625_reg_block_write(ctx, ctx->i2c.rx_p0_client,
+ AP_AUX_BUFF_START, len, buf);
/* Enable aux access */
ret |= anx7625_write_or(ctx, ctx->i2c.rx_p0_client,
AP_AUX_CTRL_STATUS, AP_AUX_CTRL_OP_EN);
@@ -263,6 +282,11 @@ static int anx7625_aux_dpcd_read(struct anx7625_data *ctx,
return ret;
}

+ /* Write done */
+ if (op == DPCD_WRITE)
+ return 0;
+
+ /* Read done, read out dpcd data */
ret = anx7625_reg_block_read(ctx, ctx->i2c.rx_p0_client,
AP_AUX_BUFF_START, len, buf);
if (ret < 0) {
@@ -845,7 +869,7 @@ static int anx7625_hdcp_enable(struct anx7625_data *ctx)
}

/* Read downstream capability */
- anx7625_aux_dpcd_read(ctx, 0x68028, 1, &bcap);
+ anx7625_aux_dpcd_trans(ctx, DPCD_READ, 0x68028, 1, &bcap);
if (!(bcap & 0x01)) {
pr_warn("downstream not support HDCP 1.4, cap(%x).\n", bcap);
return 0;
@@ -918,6 +942,7 @@ static void anx7625_dp_stop(struct anx7625_data *ctx)
{
struct device *dev = &ctx->client->dev;
int ret;
+ u8 data;

DRM_DEV_DEBUG_DRIVER(dev, "stop dp output\n");

@@ -929,6 +954,11 @@ static void anx7625_dp_stop(struct anx7625_data *ctx)
ret |= anx7625_write_and(ctx, ctx->i2c.tx_p2_client, 0x08, 0x7f);

ret |= anx7625_video_mute_control(ctx, 1);
+
+ DRM_DEV_DEBUG_DRIVER(dev, "notify downstream enter into standby\n");
+ /* Downstream monitor enter into standby mode */
+ data = 2;
+ ret |= anx7625_aux_dpcd_trans(ctx, DPCD_WRITE, 0x000600, 1, &data);
if (ret < 0)
DRM_DEV_ERROR(dev, "IO error : mute video fail\n");

--
2.25.1