diff mbox

[v2] drm/bridge: dw_hdmi: support i2c extended read mode

Message ID 1489978651-16647-1-git-send-email-nickey.yang@rock-chips.com (mailing list archive)
State New, archived
Headers show

Commit Message

Nickey Yang March 20, 2017, 2:57 a.m. UTC
"I2C Master Interface Extended Read Mode" implements a segment
pointer-based read operation using the Special Register configuration.

This patch fix https://patchwork.kernel.org/patch/7098101/ mentioned
"The current implementation does not support "I2C Master Interface
Extended Read Mode" to read data addressed by non-zero segment
pointer, this means that if EDID has more than 1 extension blocks"

With this patch,dw-hdmi can read EDID data with 1/2/4 blocks.

Signed-off-by: Nickey Yang <nickey.yang@rock-chips.com>
Reviewed-by: Douglas Anderson <dianders@chromium.org>
---
 drivers/gpu/drm/bridge/dw-hdmi.c | 38 ++++++++++++++++++++++++--------------
 1 file changed, 24 insertions(+), 14 deletions(-)

Comments

Jose Abreu March 20, 2017, 11:13 a.m. UTC | #1
Hi Nickey,


On 20-03-2017 02:57, Nickey Yang wrote:
> "I2C Master Interface Extended Read Mode" implements a segment
> pointer-based read operation using the Special Register configuration.
>
> This patch fix https://urldefense.proofpoint.com/v2/url?u=https-3A__patchwork.kernel.org_patch_7098101_&d=DwIBAg&c=DPL6_X_6JkXFx7AXWqB0tg&r=yaVFU4TjGY0gVF8El1uKcisy6TPsyCl9uN7Wsis-qhY&m=cFlvlFSQCohfzkddQ6Jl6IlJ766epJ2Rsb329_KQEKo&s=4l-Ct5Bh-AZ0pzXWMJr64E8PVl56QkdSiHwxB3eHmz4&e=  mentioned
> "The current implementation does not support "I2C Master Interface
> Extended Read Mode" to read data addressed by non-zero segment
> pointer, this means that if EDID has more than 1 extension blocks"
>
> With this patch,dw-hdmi can read EDID data with 1/2/4 blocks.
>
> Signed-off-by: Nickey Yang <nickey.yang@rock-chips.com>
> Reviewed-by: Douglas Anderson <dianders@chromium.org>

Reviewed-by: Jose Abreu <joabreu@synopsys.com>

Best regards,
Jose Miguel Abreu

> ---
>  drivers/gpu/drm/bridge/dw-hdmi.c | 38 ++++++++++++++++++++++++--------------
>  1 file changed, 24 insertions(+), 14 deletions(-)
>
> diff --git a/drivers/gpu/drm/bridge/dw-hdmi.c b/drivers/gpu/drm/bridge/dw-hdmi.c
> index 9a9ec27..3b93655 100644
> --- a/drivers/gpu/drm/bridge/dw-hdmi.c
> +++ b/drivers/gpu/drm/bridge/dw-hdmi.c
> @@ -32,6 +32,7 @@
>  #include "dw-hdmi.h"
>  #include "dw-hdmi-audio.h"
>  
> +#define DDC_SEGMENT_ADDR	0x30
>  #define HDMI_EDID_LEN		512
>  
>  #define RGB			0
> @@ -111,6 +112,7 @@ struct dw_hdmi_i2c {
>  
>  	u8			slave_reg;
>  	bool			is_regaddr;
> +	bool			is_segment;
>  };
>  
>  struct dw_hdmi_phy_data {
> @@ -258,8 +260,12 @@ static int dw_hdmi_i2c_read(struct dw_hdmi *hdmi,
>  		reinit_completion(&i2c->cmp);
>  
>  		hdmi_writeb(hdmi, i2c->slave_reg++, HDMI_I2CM_ADDRESS);
> -		hdmi_writeb(hdmi, HDMI_I2CM_OPERATION_READ,
> -			    HDMI_I2CM_OPERATION);
> +		if (i2c->is_segment)
> +			hdmi_writeb(hdmi, HDMI_I2CM_OPERATION_READ_EXT,
> +				    HDMI_I2CM_OPERATION);
> +		else
> +			hdmi_writeb(hdmi, HDMI_I2CM_OPERATION_READ,
> +				    HDMI_I2CM_OPERATION);
>  
>  		stat = wait_for_completion_timeout(&i2c->cmp, HZ / 10);
>  		if (!stat)
> @@ -271,6 +277,7 @@ static int dw_hdmi_i2c_read(struct dw_hdmi *hdmi,
>  
>  		*buf++ = hdmi_readb(hdmi, HDMI_I2CM_DATAI);
>  	}
> +	i2c->is_segment = false;
>  
>  	return 0;
>  }
> @@ -320,12 +327,6 @@ static int dw_hdmi_i2c_xfer(struct i2c_adapter *adap,
>  	dev_dbg(hdmi->dev, "xfer: num: %d, addr: %#x\n", num, addr);
>  
>  	for (i = 0; i < num; i++) {
> -		if (msgs[i].addr != addr) {
> -			dev_warn(hdmi->dev,
> -				 "unsupported transfer, changed slave address\n");
> -			return -EOPNOTSUPP;
> -		}
> -
>  		if (msgs[i].len == 0) {
>  			dev_dbg(hdmi->dev,
>  				"unsupported transfer %d/%d, no data\n",
> @@ -345,15 +346,24 @@ static int dw_hdmi_i2c_xfer(struct i2c_adapter *adap,
>  	/* Set slave device register address on transfer */
>  	i2c->is_regaddr = false;
>  
> +	/* Set segment pointer for I2C extended read mode operation */
> +	i2c->is_segment = false;
> +
>  	for (i = 0; i < num; i++) {
>  		dev_dbg(hdmi->dev, "xfer: num: %d/%d, len: %d, flags: %#x\n",
>  			i + 1, num, msgs[i].len, msgs[i].flags);
> -
> -		if (msgs[i].flags & I2C_M_RD)
> -			ret = dw_hdmi_i2c_read(hdmi, msgs[i].buf, msgs[i].len);
> -		else
> -			ret = dw_hdmi_i2c_write(hdmi, msgs[i].buf, msgs[i].len);
> -
> +		if (msgs[i].addr == DDC_SEGMENT_ADDR && msgs[i].len == 1) {
> +			i2c->is_segment = true;
> +			hdmi_writeb(hdmi, DDC_SEGMENT_ADDR, HDMI_I2CM_SEGADDR);
> +			hdmi_writeb(hdmi, *msgs[i].buf, HDMI_I2CM_SEGPTR);
> +		} else {
> +			if (msgs[i].flags & I2C_M_RD)
> +				ret = dw_hdmi_i2c_read(hdmi, msgs[i].buf,
> +						       msgs[i].len);
> +			else
> +				ret = dw_hdmi_i2c_write(hdmi, msgs[i].buf,
> +							msgs[i].len);
> +		}
>  		if (ret < 0)
>  			break;
>  	}
Vladimir Zapolskiy March 20, 2017, 11:55 a.m. UTC | #2
Hi Nickey,

On 03/20/2017 04:57 AM, Nickey Yang wrote:
> "I2C Master Interface Extended Read Mode" implements a segment
> pointer-based read operation using the Special Register configuration.
> 
> This patch fix https://patchwork.kernel.org/patch/7098101/ mentioned
> "The current implementation does not support "I2C Master Interface
> Extended Read Mode" to read data addressed by non-zero segment
> pointer, this means that if EDID has more than 1 extension blocks"

... EDID reading operation won't succeed.

Indeed.

> 
> With this patch,dw-hdmi can read EDID data with 1/2/4 blocks.
> 
> Signed-off-by: Nickey Yang <nickey.yang@rock-chips.com>
> Reviewed-by: Douglas Anderson <dianders@chromium.org>
> ---

Unfortunately I don't have a chance to test the change thoroughly, but
from what I see the implementation is correct. Thank you for the change.

Please feel free to update the commit message and add my

Acked-by: Vladimir Zapolskiy <vladimir_zapolskiy@mentor.com>

--
With best wishes,
Vladimir
Archit Taneja March 21, 2017, 7:48 a.m. UTC | #3
On 03/20/2017 08:27 AM, Nickey Yang wrote:
> "I2C Master Interface Extended Read Mode" implements a segment
> pointer-based read operation using the Special Register configuration.
>
> This patch fix https://patchwork.kernel.org/patch/7098101/ mentioned
> "The current implementation does not support "I2C Master Interface
> Extended Read Mode" to read data addressed by non-zero segment
> pointer, this means that if EDID has more than 1 extension blocks"

Queued to drm-misc-next after fixing up commit message.

Archit

>
> With this patch,dw-hdmi can read EDID data with 1/2/4 blocks.
>
> Signed-off-by: Nickey Yang <nickey.yang@rock-chips.com>
> Reviewed-by: Douglas Anderson <dianders@chromium.org>
> ---
>  drivers/gpu/drm/bridge/dw-hdmi.c | 38 ++++++++++++++++++++++++--------------
>  1 file changed, 24 insertions(+), 14 deletions(-)
>
> diff --git a/drivers/gpu/drm/bridge/dw-hdmi.c b/drivers/gpu/drm/bridge/dw-hdmi.c
> index 9a9ec27..3b93655 100644
> --- a/drivers/gpu/drm/bridge/dw-hdmi.c
> +++ b/drivers/gpu/drm/bridge/dw-hdmi.c
> @@ -32,6 +32,7 @@
>  #include "dw-hdmi.h"
>  #include "dw-hdmi-audio.h"
>
> +#define DDC_SEGMENT_ADDR	0x30
>  #define HDMI_EDID_LEN		512
>
>  #define RGB			0
> @@ -111,6 +112,7 @@ struct dw_hdmi_i2c {
>
>  	u8			slave_reg;
>  	bool			is_regaddr;
> +	bool			is_segment;
>  };
>
>  struct dw_hdmi_phy_data {
> @@ -258,8 +260,12 @@ static int dw_hdmi_i2c_read(struct dw_hdmi *hdmi,
>  		reinit_completion(&i2c->cmp);
>
>  		hdmi_writeb(hdmi, i2c->slave_reg++, HDMI_I2CM_ADDRESS);
> -		hdmi_writeb(hdmi, HDMI_I2CM_OPERATION_READ,
> -			    HDMI_I2CM_OPERATION);
> +		if (i2c->is_segment)
> +			hdmi_writeb(hdmi, HDMI_I2CM_OPERATION_READ_EXT,
> +				    HDMI_I2CM_OPERATION);
> +		else
> +			hdmi_writeb(hdmi, HDMI_I2CM_OPERATION_READ,
> +				    HDMI_I2CM_OPERATION);
>
>  		stat = wait_for_completion_timeout(&i2c->cmp, HZ / 10);
>  		if (!stat)
> @@ -271,6 +277,7 @@ static int dw_hdmi_i2c_read(struct dw_hdmi *hdmi,
>
>  		*buf++ = hdmi_readb(hdmi, HDMI_I2CM_DATAI);
>  	}
> +	i2c->is_segment = false;
>
>  	return 0;
>  }
> @@ -320,12 +327,6 @@ static int dw_hdmi_i2c_xfer(struct i2c_adapter *adap,
>  	dev_dbg(hdmi->dev, "xfer: num: %d, addr: %#x\n", num, addr);
>
>  	for (i = 0; i < num; i++) {
> -		if (msgs[i].addr != addr) {
> -			dev_warn(hdmi->dev,
> -				 "unsupported transfer, changed slave address\n");
> -			return -EOPNOTSUPP;
> -		}
> -
>  		if (msgs[i].len == 0) {
>  			dev_dbg(hdmi->dev,
>  				"unsupported transfer %d/%d, no data\n",
> @@ -345,15 +346,24 @@ static int dw_hdmi_i2c_xfer(struct i2c_adapter *adap,
>  	/* Set slave device register address on transfer */
>  	i2c->is_regaddr = false;
>
> +	/* Set segment pointer for I2C extended read mode operation */
> +	i2c->is_segment = false;
> +
>  	for (i = 0; i < num; i++) {
>  		dev_dbg(hdmi->dev, "xfer: num: %d/%d, len: %d, flags: %#x\n",
>  			i + 1, num, msgs[i].len, msgs[i].flags);
> -
> -		if (msgs[i].flags & I2C_M_RD)
> -			ret = dw_hdmi_i2c_read(hdmi, msgs[i].buf, msgs[i].len);
> -		else
> -			ret = dw_hdmi_i2c_write(hdmi, msgs[i].buf, msgs[i].len);
> -
> +		if (msgs[i].addr == DDC_SEGMENT_ADDR && msgs[i].len == 1) {
> +			i2c->is_segment = true;
> +			hdmi_writeb(hdmi, DDC_SEGMENT_ADDR, HDMI_I2CM_SEGADDR);
> +			hdmi_writeb(hdmi, *msgs[i].buf, HDMI_I2CM_SEGPTR);
> +		} else {
> +			if (msgs[i].flags & I2C_M_RD)
> +				ret = dw_hdmi_i2c_read(hdmi, msgs[i].buf,
> +						       msgs[i].len);
> +			else
> +				ret = dw_hdmi_i2c_write(hdmi, msgs[i].buf,
> +							msgs[i].len);
> +		}
>  		if (ret < 0)
>  			break;
>  	}
>
diff mbox

Patch

diff --git a/drivers/gpu/drm/bridge/dw-hdmi.c b/drivers/gpu/drm/bridge/dw-hdmi.c
index 9a9ec27..3b93655 100644
--- a/drivers/gpu/drm/bridge/dw-hdmi.c
+++ b/drivers/gpu/drm/bridge/dw-hdmi.c
@@ -32,6 +32,7 @@ 
 #include "dw-hdmi.h"
 #include "dw-hdmi-audio.h"
 
+#define DDC_SEGMENT_ADDR	0x30
 #define HDMI_EDID_LEN		512
 
 #define RGB			0
@@ -111,6 +112,7 @@  struct dw_hdmi_i2c {
 
 	u8			slave_reg;
 	bool			is_regaddr;
+	bool			is_segment;
 };
 
 struct dw_hdmi_phy_data {
@@ -258,8 +260,12 @@  static int dw_hdmi_i2c_read(struct dw_hdmi *hdmi,
 		reinit_completion(&i2c->cmp);
 
 		hdmi_writeb(hdmi, i2c->slave_reg++, HDMI_I2CM_ADDRESS);
-		hdmi_writeb(hdmi, HDMI_I2CM_OPERATION_READ,
-			    HDMI_I2CM_OPERATION);
+		if (i2c->is_segment)
+			hdmi_writeb(hdmi, HDMI_I2CM_OPERATION_READ_EXT,
+				    HDMI_I2CM_OPERATION);
+		else
+			hdmi_writeb(hdmi, HDMI_I2CM_OPERATION_READ,
+				    HDMI_I2CM_OPERATION);
 
 		stat = wait_for_completion_timeout(&i2c->cmp, HZ / 10);
 		if (!stat)
@@ -271,6 +277,7 @@  static int dw_hdmi_i2c_read(struct dw_hdmi *hdmi,
 
 		*buf++ = hdmi_readb(hdmi, HDMI_I2CM_DATAI);
 	}
+	i2c->is_segment = false;
 
 	return 0;
 }
@@ -320,12 +327,6 @@  static int dw_hdmi_i2c_xfer(struct i2c_adapter *adap,
 	dev_dbg(hdmi->dev, "xfer: num: %d, addr: %#x\n", num, addr);
 
 	for (i = 0; i < num; i++) {
-		if (msgs[i].addr != addr) {
-			dev_warn(hdmi->dev,
-				 "unsupported transfer, changed slave address\n");
-			return -EOPNOTSUPP;
-		}
-
 		if (msgs[i].len == 0) {
 			dev_dbg(hdmi->dev,
 				"unsupported transfer %d/%d, no data\n",
@@ -345,15 +346,24 @@  static int dw_hdmi_i2c_xfer(struct i2c_adapter *adap,
 	/* Set slave device register address on transfer */
 	i2c->is_regaddr = false;
 
+	/* Set segment pointer for I2C extended read mode operation */
+	i2c->is_segment = false;
+
 	for (i = 0; i < num; i++) {
 		dev_dbg(hdmi->dev, "xfer: num: %d/%d, len: %d, flags: %#x\n",
 			i + 1, num, msgs[i].len, msgs[i].flags);
-
-		if (msgs[i].flags & I2C_M_RD)
-			ret = dw_hdmi_i2c_read(hdmi, msgs[i].buf, msgs[i].len);
-		else
-			ret = dw_hdmi_i2c_write(hdmi, msgs[i].buf, msgs[i].len);
-
+		if (msgs[i].addr == DDC_SEGMENT_ADDR && msgs[i].len == 1) {
+			i2c->is_segment = true;
+			hdmi_writeb(hdmi, DDC_SEGMENT_ADDR, HDMI_I2CM_SEGADDR);
+			hdmi_writeb(hdmi, *msgs[i].buf, HDMI_I2CM_SEGPTR);
+		} else {
+			if (msgs[i].flags & I2C_M_RD)
+				ret = dw_hdmi_i2c_read(hdmi, msgs[i].buf,
+						       msgs[i].len);
+			else
+				ret = dw_hdmi_i2c_write(hdmi, msgs[i].buf,
+							msgs[i].len);
+		}
 		if (ret < 0)
 			break;
 	}