DRM: BRIDGE: TFP410: Add i2c support

[PATCH 4/4] DRM: BRIDGE: TFP410: If connected, use I2C for polled HPD status.

Posted by Jonathan Cormier 2 years, 7 months ago

From: Michael Williamson <michael.williamson@criticallink.com>

If the I2C bus is connected on the TFP410, then use the register
status bit to determine connection state.  This is needed, in particular,
for polling the state when the Hot Plug detect is not connected to
a controlling CPU via GPIO/IRQ lane.

Signed-off-by: Michael Williamson <michael.williamson@criticallink.com>
Signed-off-by: Jonathan Cormier <jcormier@criticallink.com>
---
 drivers/gpu/drm/bridge/ti-tfp410.c | 13 +++++++++++++
 1 file changed, 13 insertions(+)

diff --git a/drivers/gpu/drm/bridge/ti-tfp410.c b/drivers/gpu/drm/bridge/ti-tfp410.c
index 837e1f81a0ff..ac216eaec3c8 100644
--- a/drivers/gpu/drm/bridge/ti-tfp410.c
+++ b/drivers/gpu/drm/bridge/ti-tfp410.c
@@ -28,6 +28,9 @@
 #define TFP410_BIT_BSEL BIT(2)
 #define TFP410_BIT_DSEL BIT(3)
 
+#define TFP410_REG_CTL_2_MODE	0x09
+#define TFP410_BIT_HTPLG BIT(1)
+
 static const struct regmap_config tfp410_regmap_config = {
 	.reg_bits = 8,
 	.val_bits = 8,
@@ -105,6 +108,16 @@ static enum drm_connector_status
 tfp410_connector_detect(struct drm_connector *connector, bool force)
 {
 	struct tfp410 *dvi = drm_connector_to_tfp410(connector);
+	u32 val;
+	unsigned int ret;
+
+	if (dvi->i2c) {
+		ret = regmap_test_bits(dvi->regmap, TFP410_REG_CTL_2_MODE, TFP410_BIT_HTPLG);
+		if (ret < 0)
+			dev_err(dvi->dev, "%s failed to read HTPLG bit : %d\n", __func__, ret);
+		else
+			return ret ? connector_status_connected : connector_status_disconnected;
+	}
 
 	return drm_bridge_detect(dvi->next_bridge);
 }

-- 
2.25.1

Re: [PATCH 4/4] DRM: BRIDGE: TFP410: If connected, use I2C for polled HPD status.

Posted by kernel test robot 2 years, 7 months ago

Hi Jonathan,

Thank you for the patch! Perhaps something to improve:

[auto build test WARNING on 93f875a8526a291005e7f38478079526c843cbec]

url:    https://github.com/intel-lab-lkp/linux/commits/Jonathan-Cormier/dt-bindings-display-bridge-tfp410-Add-tfp410-i2c-example/20230128-183627
base:   93f875a8526a291005e7f38478079526c843cbec
patch link:    https://lore.kernel.org/r/20230125-tfp410_i2c-v1-4-66a4d4e390b7%40criticallink.com
patch subject: [PATCH 4/4] DRM: BRIDGE: TFP410: If connected, use I2C for polled HPD status.
config: i386-randconfig-a006 (https://download.01.org/0day-ci/archive/20230129/202301290803.ouS19eab-lkp@intel.com/config)
compiler: clang version 14.0.6 (https://github.com/llvm/llvm-project f28c006a5895fc0e329fe15fead81e37457cb1d1)
reproduce (this is a W=1 build):
        wget https://raw.githubusercontent.com/intel/lkp-tests/master/sbin/make.cross -O ~/bin/make.cross
        chmod +x ~/bin/make.cross
        # https://github.com/intel-lab-lkp/linux/commit/c4659fa4c02b62087c095ca99978e5eac8b490de
        git remote add linux-review https://github.com/intel-lab-lkp/linux
        git fetch --no-tags linux-review Jonathan-Cormier/dt-bindings-display-bridge-tfp410-Add-tfp410-i2c-example/20230128-183627
        git checkout c4659fa4c02b62087c095ca99978e5eac8b490de
        # save the config file
        mkdir build_dir && cp config build_dir/.config
        COMPILER_INSTALL_PATH=$HOME/0day COMPILER=clang make.cross W=1 O=build_dir ARCH=i386 olddefconfig
        COMPILER_INSTALL_PATH=$HOME/0day COMPILER=clang make.cross W=1 O=build_dir ARCH=i386 SHELL=/bin/bash drivers/gpu/drm/bridge/

If you fix the issue, kindly add following tag where applicable
| Reported-by: kernel test robot <lkp@intel.com>

All warnings (new ones prefixed by >>):

>> drivers/gpu/drm/bridge/ti-tfp410.c:111:6: warning: unused variable 'val' [-Wunused-variable]
           u32 val;
               ^
   1 warning generated.


vim +/val +111 drivers/gpu/drm/bridge/ti-tfp410.c

   106	
   107	static enum drm_connector_status
   108	tfp410_connector_detect(struct drm_connector *connector, bool force)
   109	{
   110		struct tfp410 *dvi = drm_connector_to_tfp410(connector);
 > 111		u32 val;
   112		unsigned int ret;
   113	
   114		if (dvi->i2c) {
   115			ret = regmap_test_bits(dvi->regmap, TFP410_REG_CTL_2_MODE, TFP410_BIT_HTPLG);
   116			if (ret < 0)
   117				dev_err(dvi->dev, "%s failed to read HTPLG bit : %d\n", __func__, ret);
   118			else
   119				return ret ? connector_status_connected : connector_status_disconnected;
   120		}
   121	
   122		return drm_bridge_detect(dvi->next_bridge);
   123	}
   124	

-- 
0-DAY CI Kernel Test Service
https://github.com/intel/lkp-tests

Re: [PATCH 4/4] DRM: BRIDGE: TFP410: If connected, use I2C for polled HPD status.

Posted by Jon Cormier 2 years, 7 months ago

On Sat, Jan 28, 2023 at 7:47 PM kernel test robot <lkp@intel.com> wrote:
>
> Hi Jonathan,
>
> Thank you for the patch! Perhaps something to improve:
Good bot.
>
> [auto build test WARNING on 93f875a8526a291005e7f38478079526c843cbec]
>
> url:    https://github.com/intel-lab-lkp/linux/commits/Jonathan-Cormier/dt-bindings-display-bridge-tfp410-Add-tfp410-i2c-example/20230128-183627
> base:   93f875a8526a291005e7f38478079526c843cbec
> patch link:    https://lore.kernel.org/r/20230125-tfp410_i2c-v1-4-66a4d4e390b7%40criticallink.com
> patch subject: [PATCH 4/4] DRM: BRIDGE: TFP410: If connected, use I2C for polled HPD status.
> config: i386-randconfig-a006 (https://download.01.org/0day-ci/archive/20230129/202301290803.ouS19eab-lkp@intel.com/config)
> compiler: clang version 14.0.6 (https://github.com/llvm/llvm-project f28c006a5895fc0e329fe15fead81e37457cb1d1)
> reproduce (this is a W=1 build):
>         wget https://raw.githubusercontent.com/intel/lkp-tests/master/sbin/make.cross -O ~/bin/make.cross
>         chmod +x ~/bin/make.cross
>         # https://github.com/intel-lab-lkp/linux/commit/c4659fa4c02b62087c095ca99978e5eac8b490de
>         git remote add linux-review https://github.com/intel-lab-lkp/linux
>         git fetch --no-tags linux-review Jonathan-Cormier/dt-bindings-display-bridge-tfp410-Add-tfp410-i2c-example/20230128-183627
>         git checkout c4659fa4c02b62087c095ca99978e5eac8b490de
>         # save the config file
>         mkdir build_dir && cp config build_dir/.config
>         COMPILER_INSTALL_PATH=$HOME/0day COMPILER=clang make.cross W=1 O=build_dir ARCH=i386 olddefconfig
>         COMPILER_INSTALL_PATH=$HOME/0day COMPILER=clang make.cross W=1 O=build_dir ARCH=i386 SHELL=/bin/bash drivers/gpu/drm/bridge/
>
> If you fix the issue, kindly add following tag where applicable
> | Reported-by: kernel test robot <lkp@intel.com>
>
> All warnings (new ones prefixed by >>):
>
> >> drivers/gpu/drm/bridge/ti-tfp410.c:111:6: warning: unused variable 'val' [-Wunused-variable]
>            u32 val;
>                ^
>    1 warning generated.
This has already been fixed in V2 of the patch series.
>
>
> vim +/val +111 drivers/gpu/drm/bridge/ti-tfp410.c
>
>    106
>    107  static enum drm_connector_status
>    108  tfp410_connector_detect(struct drm_connector *connector, bool force)
>    109  {
>    110          struct tfp410 *dvi = drm_connector_to_tfp410(connector);
>  > 111          u32 val;
>    112          unsigned int ret;
>    113
>    114          if (dvi->i2c) {
>    115                  ret = regmap_test_bits(dvi->regmap, TFP410_REG_CTL_2_MODE, TFP410_BIT_HTPLG);
>    116                  if (ret < 0)
>    117                          dev_err(dvi->dev, "%s failed to read HTPLG bit : %d\n", __func__, ret);
>    118                  else
>    119                          return ret ? connector_status_connected : connector_status_disconnected;
>    120          }
>    121
>    122          return drm_bridge_detect(dvi->next_bridge);
>    123  }
>    124
>
> --
> 0-DAY CI Kernel Test Service
> https://github.com/intel/lkp-tests

Re: [PATCH 4/4] DRM: BRIDGE: TFP410: If connected, use I2C for polled HPD status.

Posted by kernel test robot 2 years, 7 months ago

Hi Jonathan,

Thank you for the patch! Perhaps something to improve:

[auto build test WARNING on 93f875a8526a291005e7f38478079526c843cbec]

url:    https://github.com/intel-lab-lkp/linux/commits/Jonathan-Cormier/dt-bindings-display-bridge-tfp410-Add-tfp410-i2c-example/20230128-183627
base:   93f875a8526a291005e7f38478079526c843cbec
patch link:    https://lore.kernel.org/r/20230125-tfp410_i2c-v1-4-66a4d4e390b7%40criticallink.com
patch subject: [PATCH 4/4] DRM: BRIDGE: TFP410: If connected, use I2C for polled HPD status.
config: x86_64-allyesconfig (https://download.01.org/0day-ci/archive/20230129/202301290252.zgcWeegX-lkp@intel.com/config)
compiler: gcc-11 (Debian 11.3.0-8) 11.3.0
reproduce (this is a W=1 build):
        # https://github.com/intel-lab-lkp/linux/commit/c4659fa4c02b62087c095ca99978e5eac8b490de
        git remote add linux-review https://github.com/intel-lab-lkp/linux
        git fetch --no-tags linux-review Jonathan-Cormier/dt-bindings-display-bridge-tfp410-Add-tfp410-i2c-example/20230128-183627
        git checkout c4659fa4c02b62087c095ca99978e5eac8b490de
        # save the config file
        mkdir build_dir && cp config build_dir/.config
        make W=1 O=build_dir ARCH=x86_64 olddefconfig
        make W=1 O=build_dir ARCH=x86_64 SHELL=/bin/bash drivers/gpu/

If you fix the issue, kindly add following tag where applicable
| Reported-by: kernel test robot <lkp@intel.com>

All warnings (new ones prefixed by >>):

   drivers/gpu/drm/bridge/ti-tfp410.c: In function 'tfp410_connector_detect':
>> drivers/gpu/drm/bridge/ti-tfp410.c:111:13: warning: unused variable 'val' [-Wunused-variable]
     111 |         u32 val;
         |             ^~~


vim +/val +111 drivers/gpu/drm/bridge/ti-tfp410.c

   106	
   107	static enum drm_connector_status
   108	tfp410_connector_detect(struct drm_connector *connector, bool force)
   109	{
   110		struct tfp410 *dvi = drm_connector_to_tfp410(connector);
 > 111		u32 val;
   112		unsigned int ret;
   113	
   114		if (dvi->i2c) {
   115			ret = regmap_test_bits(dvi->regmap, TFP410_REG_CTL_2_MODE, TFP410_BIT_HTPLG);
   116			if (ret < 0)
   117				dev_err(dvi->dev, "%s failed to read HTPLG bit : %d\n", __func__, ret);
   118			else
   119				return ret ? connector_status_connected : connector_status_disconnected;
   120		}
   121	
   122		return drm_bridge_detect(dvi->next_bridge);
   123	}
   124	

-- 
0-DAY CI Kernel Test Service
https://github.com/intel/lkp-tests