[PATCH 0/3] ast: Fix I2C corner cases wrt init/cleanup

[PATCH 0/3] ast: Fix I2C corner cases wrt init/cleanup

[Thomas Zimmermann]

The VGA connector in ast is supposed to work without I2C. Currently,
this isn't correctly implemented in several places. Fix this. Also
add managed cleanup of the I2C code, and fail if the connector setup
fail.

Tested on AST2100 hardware.

Thomas Zimmermann (3):
  drm/ast: Handle failed I2C initialization gracefully
  drm/ast: Convert I2C code to managed cleanup
  drm/ast: Fail if connector initialization fails

 drivers/gpu/drm/ast/ast_mode.c | 52 ++++++++++++++++++----------------
 1 file changed, 27 insertions(+), 25 deletions(-)


base-commit: 6a8f90ec433e2f5de5fc16d7a4839771b7027cc0
--
2.34.0

[PATCH 1/3] drm/ast: Handle failed I2C initialization gracefully

[Thomas Zimmermann]

I2C initialization is allowed to fail. In this case, create a connector
without DDC adapter. The current code would dereference a NULL pointer.

Reading the modes from the connector is supposed to work without I2C
adapter. Add the respective test.

Signed-off-by: Thomas Zimmermann <tzimmermann@suse.de>
---
 drivers/gpu/drm/ast/ast_mode.c | 13 ++++++++-----
 1 file changed, 8 insertions(+), 5 deletions(-)

diff --git a/drivers/gpu/drm/ast/ast_mode.c b/drivers/gpu/drm/ast/ast_mode.c
index 1e30eaeb0e1b..3f0c8c1f9777 100644
--- a/drivers/gpu/drm/ast/ast_mode.c
+++ b/drivers/gpu/drm/ast/ast_mode.c
@@ -1226,7 +1226,7 @@ static int ast_get_modes(struct drm_connector *connector)
 		else
 			kfree(edid);
 	}
-	if (!flags)
+	if (!flags && ast_connector->i2c)
 		edid = drm_get_edid(connector, &ast_connector->i2c->adapter);
 	if (edid) {
 		drm_connector_update_edid_property(&ast_connector->base, edid);
@@ -1332,10 +1332,13 @@ static int ast_connector_init(struct drm_device *dev)
 	if (!ast_connector->i2c)
 		drm_err(dev, "failed to add ddc bus for connector\n");
 
-	drm_connector_init_with_ddc(dev, connector,
-				    &ast_connector_funcs,
-				    DRM_MODE_CONNECTOR_VGA,
-				    &ast_connector->i2c->adapter);
+	if (ast_connector->i2c)
+		drm_connector_init_with_ddc(dev, connector, &ast_connector_funcs,
+					    DRM_MODE_CONNECTOR_VGA,
+					    &ast_connector->i2c->adapter);
+	else
+		drm_connector_init(dev, connector, &ast_connector_funcs,
+				   DRM_MODE_CONNECTOR_VGA);
 
 	drm_connector_helper_add(connector, &ast_connector_helper_funcs);
 
-- 
2.34.0

Re: [PATCH 1/3] drm/ast: Handle failed I2C initialization gracefully

[Maxime Ripard]

[-- Attachment #1: Type: text/plain, Size: 453 bytes --]

On Wed, Dec 01, 2021 at 04:30:58PM +0100, Thomas Zimmermann wrote:
> I2C initialization is allowed to fail. In this case, create a connector
> without DDC adapter. The current code would dereference a NULL pointer.
> 
> Reading the modes from the connector is supposed to work without I2C
> adapter. Add the respective test.
> 
> Signed-off-by: Thomas Zimmermann <tzimmermann@suse.de>

Reviewed-by: Maxime Ripard <maxime@cerno.tech>

Maxime

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[PATCH 2/3] drm/ast: Convert I2C code to managed cleanup

[Thomas Zimmermann]

Release the I2C adapter as part of the DRM device cleanup.

Signed-off-by: Thomas Zimmermann <tzimmermann@suse.de>
---
 drivers/gpu/drm/ast/ast_mode.c | 36 +++++++++++++++-------------------
 1 file changed, 16 insertions(+), 20 deletions(-)

diff --git a/drivers/gpu/drm/ast/ast_mode.c b/drivers/gpu/drm/ast/ast_mode.c
index 3f0c8c1f9777..a84dced95440 100644
--- a/drivers/gpu/drm/ast/ast_mode.c
+++ b/drivers/gpu/drm/ast/ast_mode.c
@@ -40,6 +40,7 @@
 #include <drm/drm_gem_atomic_helper.h>
 #include <drm/drm_gem_framebuffer_helper.h>
 #include <drm/drm_gem_vram_helper.h>
+#include <drm/drm_managed.h>
 #include <drm/drm_plane_helper.h>
 #include <drm/drm_probe_helper.h>
 #include <drm/drm_simple_kms_helper.h>
@@ -48,7 +49,6 @@
 #include "ast_tables.h"
 
 static struct ast_i2c_chan *ast_i2c_create(struct drm_device *dev);
-static void ast_i2c_destroy(struct ast_i2c_chan *i2c);
 
 static inline void ast_load_palette_index(struct ast_private *ast,
 				     u8 index, u8 red, u8 green,
@@ -1300,14 +1300,6 @@ static enum drm_mode_status ast_mode_valid(struct drm_connector *connector,
 	return flags;
 }
 
-static void ast_connector_destroy(struct drm_connector *connector)
-{
-	struct ast_connector *ast_connector = to_ast_connector(connector);
-
-	ast_i2c_destroy(ast_connector->i2c);
-	drm_connector_cleanup(connector);
-}
-
 static const struct drm_connector_helper_funcs ast_connector_helper_funcs = {
 	.get_modes = ast_get_modes,
 	.mode_valid = ast_mode_valid,
@@ -1316,7 +1308,7 @@ static const struct drm_connector_helper_funcs ast_connector_helper_funcs = {
 static const struct drm_connector_funcs ast_connector_funcs = {
 	.reset = drm_atomic_helper_connector_reset,
 	.fill_modes = drm_helper_probe_single_connector_modes,
-	.destroy = ast_connector_destroy,
+	.destroy = drm_connector_cleanup,
 	.atomic_duplicate_state = drm_atomic_helper_connector_duplicate_state,
 	.atomic_destroy_state = drm_atomic_helper_connector_destroy_state,
 };
@@ -1493,6 +1485,14 @@ static void set_data(void *i2c_priv, int data)
 	}
 }
 
+static void ast_i2c_release(struct drm_device *dev, void *res)
+{
+	struct ast_i2c_chan *i2c = res;
+
+	i2c_del_adapter(&i2c->adapter);
+	kfree(i2c);
+}
+
 static struct ast_i2c_chan *ast_i2c_create(struct drm_device *dev)
 {
 	struct ast_i2c_chan *i2c;
@@ -1521,19 +1521,15 @@ static struct ast_i2c_chan *ast_i2c_create(struct drm_device *dev)
 	ret = i2c_bit_add_bus(&i2c->adapter);
 	if (ret) {
 		drm_err(dev, "Failed to register bit i2c\n");
-		goto out_free;
+		goto out_kfree;
 	}
 
+	ret = drmm_add_action_or_reset(dev, ast_i2c_release, i2c);
+	if (ret)
+		return NULL;
 	return i2c;
-out_free:
-	kfree(i2c);
-	return NULL;
-}
 
-static void ast_i2c_destroy(struct ast_i2c_chan *i2c)
-{
-	if (!i2c)
-		return;
-	i2c_del_adapter(&i2c->adapter);
+out_kfree:
 	kfree(i2c);
+	return NULL;
 }
-- 
2.34.0

Re: [PATCH 2/3] drm/ast: Convert I2C code to managed cleanup

[Maxime Ripard]

[-- Attachment #1: Type: text/plain, Size: 252 bytes --]

On Wed, Dec 01, 2021 at 04:30:59PM +0100, Thomas Zimmermann wrote:
> Release the I2C adapter as part of the DRM device cleanup.
> 
> Signed-off-by: Thomas Zimmermann <tzimmermann@suse.de>

Reviewed-by: Maxime Ripard <maxime@cerno.tech>

Maxime

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[PATCH 3/3] drm/ast: Fail if connector initialization fails

[Thomas Zimmermann]

Update the connector code to fail if the connector could not be
initialized. The current code just ignored the error and failed
later when the connector was supposed to be used.

Signed-off-by: Thomas Zimmermann <tzimmermann@suse.de>
---
 drivers/gpu/drm/ast/ast_mode.c | 13 ++++++++-----
 1 file changed, 8 insertions(+), 5 deletions(-)

diff --git a/drivers/gpu/drm/ast/ast_mode.c b/drivers/gpu/drm/ast/ast_mode.c
index a84dced95440..c988991cad33 100644
--- a/drivers/gpu/drm/ast/ast_mode.c
+++ b/drivers/gpu/drm/ast/ast_mode.c
@@ -1319,18 +1319,21 @@ static int ast_connector_init(struct drm_device *dev)
 	struct ast_connector *ast_connector = &ast->connector;
 	struct drm_connector *connector = &ast_connector->base;
 	struct drm_encoder *encoder = &ast->encoder;
+	int ret;
 
 	ast_connector->i2c = ast_i2c_create(dev);
 	if (!ast_connector->i2c)
 		drm_err(dev, "failed to add ddc bus for connector\n");
 
 	if (ast_connector->i2c)
-		drm_connector_init_with_ddc(dev, connector, &ast_connector_funcs,
-					    DRM_MODE_CONNECTOR_VGA,
-					    &ast_connector->i2c->adapter);
+		ret = drm_connector_init_with_ddc(dev, connector, &ast_connector_funcs,
+						  DRM_MODE_CONNECTOR_VGA,
+						  &ast_connector->i2c->adapter);
 	else
-		drm_connector_init(dev, connector, &ast_connector_funcs,
-				   DRM_MODE_CONNECTOR_VGA);
+		ret = drm_connector_init(dev, connector, &ast_connector_funcs,
+					 DRM_MODE_CONNECTOR_VGA);
+	if (ret)
+		return ret;
 
 	drm_connector_helper_add(connector, &ast_connector_helper_funcs);
 
-- 
2.34.0

Re: [PATCH 3/3] drm/ast: Fail if connector initialization fails

[Maxime Ripard]

[-- Attachment #1: Type: text/plain, Size: 377 bytes --]

On Wed, Dec 01, 2021 at 04:31:00PM +0100, Thomas Zimmermann wrote:
> Update the connector code to fail if the connector could not be
> initialized. The current code just ignored the error and failed
> later when the connector was supposed to be used.
> 
> Signed-off-by: Thomas Zimmermann <tzimmermann@suse.de>

Reviewed-by: Maxime Ripard <maxime@cerno.tech>

Maxime

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Re: [PATCH 1/3] drm/ast: Handle failed I2C initialization gracefully

[kernel test robot]

[-- Attachment #1: Type: text/plain, Size: 4255 bytes --]

CC: kbuild-all(a)lists.01.org
In-Reply-To: <20211201153100.403-2-tzimmermann@suse.de>
References: <20211201153100.403-2-tzimmermann@suse.de>
TO: Thomas Zimmermann <tzimmermann@suse.de>
TO: airlied(a)redhat.com
TO: daniel(a)ffwll.ch
TO: sam(a)ravnborg.org
CC: Thomas Zimmermann <tzimmermann@suse.de>
CC: dri-devel(a)lists.freedesktop.org

Hi Thomas,

I love your patch! Perhaps something to improve:

[auto build test WARNING on 6a8f90ec433e2f5de5fc16d7a4839771b7027cc0]

url:    https://github.com/0day-ci/linux/commits/Thomas-Zimmermann/ast-Fix-I2C-corner-cases-wrt-init-cleanup/20211201-233308
base:   6a8f90ec433e2f5de5fc16d7a4839771b7027cc0
:::::: branch date: 3 days ago
:::::: commit date: 3 days ago
config: i386-randconfig-m021-20211203 (https://download.01.org/0day-ci/archive/20211204/202112042126.N4Qr3RiC-lkp(a)intel.com/config)
compiler: gcc-9 (Debian 9.3.0-22) 9.3.0

If you fix the issue, kindly add following tag as appropriate
Reported-by: kernel test robot <lkp@intel.com>
Reported-by: Dan Carpenter <dan.carpenter@oracle.com>

smatch warnings:
drivers/gpu/drm/ast/ast_mode.c:1231 ast_get_modes() error: uninitialized symbol 'edid'.
drivers/gpu/drm/ast/ast_mode.c:1232 ast_get_modes() warn: passing freed memory 'edid'

vim +/edid +1231 drivers/gpu/drm/ast/ast_mode.c

312fec1405dd54 Dave Airlie       2012-02-29  1204  
4961eb60f14553 Thomas Zimmermann 2019-11-07  1205  /*
4961eb60f14553 Thomas Zimmermann 2019-11-07  1206   * Connector
4961eb60f14553 Thomas Zimmermann 2019-11-07  1207   */
4961eb60f14553 Thomas Zimmermann 2019-11-07  1208  
312fec1405dd54 Dave Airlie       2012-02-29  1209  static int ast_get_modes(struct drm_connector *connector)
312fec1405dd54 Dave Airlie       2012-02-29  1210  {
312fec1405dd54 Dave Airlie       2012-02-29  1211  	struct ast_connector *ast_connector = to_ast_connector(connector);
fa7dbd7688849d Thomas Zimmermann 2020-06-17  1212  	struct ast_private *ast = to_ast_private(connector->dev);
312fec1405dd54 Dave Airlie       2012-02-29  1213  	struct edid *edid;
312fec1405dd54 Dave Airlie       2012-02-29  1214  	int ret;
83c6620bae3f14 Dave Airlie       2014-03-28  1215  	bool flags = false;
6c9bd4432b2527 Gregory Williams  2021-07-30  1216  
83c6620bae3f14 Dave Airlie       2014-03-28  1217  	if (ast->tx_chip_type == AST_TX_DP501) {
83c6620bae3f14 Dave Airlie       2014-03-28  1218  		ast->dp501_maxclk = 0xff;
83c6620bae3f14 Dave Airlie       2014-03-28  1219  		edid = kmalloc(128, GFP_KERNEL);
83c6620bae3f14 Dave Airlie       2014-03-28  1220  		if (!edid)
83c6620bae3f14 Dave Airlie       2014-03-28  1221  			return -ENOMEM;
312fec1405dd54 Dave Airlie       2012-02-29  1222  
83c6620bae3f14 Dave Airlie       2014-03-28  1223  		flags = ast_dp501_read_edid(connector->dev, (u8 *)edid);
83c6620bae3f14 Dave Airlie       2014-03-28  1224  		if (flags)
83c6620bae3f14 Dave Airlie       2014-03-28  1225  			ast->dp501_maxclk = ast_get_dp501_max_clk(connector->dev);
83c6620bae3f14 Dave Airlie       2014-03-28  1226  		else
83c6620bae3f14 Dave Airlie       2014-03-28  1227  			kfree(edid);
83c6620bae3f14 Dave Airlie       2014-03-28  1228  	}
75bd8f71712a8a Thomas Zimmermann 2021-12-01  1229  	if (!flags && ast_connector->i2c)
312fec1405dd54 Dave Airlie       2012-02-29  1230  		edid = drm_get_edid(connector, &ast_connector->i2c->adapter);
312fec1405dd54 Dave Airlie       2012-02-29 @1231  	if (edid) {
c555f02371c338 Daniel Vetter     2018-07-09 @1232  		drm_connector_update_edid_property(&ast_connector->base, edid);
312fec1405dd54 Dave Airlie       2012-02-29  1233  		ret = drm_add_edid_modes(connector, edid);
993dcb05e47e35 Jani Nikula       2012-08-15  1234  		kfree(edid);
312fec1405dd54 Dave Airlie       2012-02-29  1235  		return ret;
6c9bd4432b2527 Gregory Williams  2021-07-30  1236  	}
c555f02371c338 Daniel Vetter     2018-07-09  1237  	drm_connector_update_edid_property(&ast_connector->base, NULL);
312fec1405dd54 Dave Airlie       2012-02-29  1238  	return 0;
312fec1405dd54 Dave Airlie       2012-02-29  1239  }
312fec1405dd54 Dave Airlie       2012-02-29  1240  

---
0-DAY CI Kernel Test Service, Intel Corporation
https://lists.01.org/hyperkitty/list/kbuild-all(a)lists.01.org

Re: [PATCH 1/3] drm/ast: Handle failed I2C initialization gracefully

[Dan Carpenter]

[-- Attachment #1: Type: text/plain, Size: 3840 bytes --]

Hi Thomas,

url:    https://github.com/0day-ci/linux/commits/Thomas-Zimmermann/ast-Fix-I2C-corner-cases-wrt-init-cleanup/20211201-233308
base:   6a8f90ec433e2f5de5fc16d7a4839771b7027cc0
config: i386-randconfig-m021-20211203 (https://download.01.org/0day-ci/archive/20211204/202112042126.N4Qr3RiC-lkp(a)intel.com/config)
compiler: gcc-9 (Debian 9.3.0-22) 9.3.0

If you fix the issue, kindly add following tag as appropriate
Reported-by: kernel test robot <lkp@intel.com>
Reported-by: Dan Carpenter <dan.carpenter@oracle.com>

smatch warnings:
drivers/gpu/drm/ast/ast_mode.c:1231 ast_get_modes() error: uninitialized symbol 'edid'.
drivers/gpu/drm/ast/ast_mode.c:1232 ast_get_modes() warn: passing freed memory 'edid'

vim +/edid +1231 drivers/gpu/drm/ast/ast_mode.c

312fec1405dd54 Dave Airlie       2012-02-29  1209  static int ast_get_modes(struct drm_connector *connector)
312fec1405dd54 Dave Airlie       2012-02-29  1210  {
312fec1405dd54 Dave Airlie       2012-02-29  1211  	struct ast_connector *ast_connector = to_ast_connector(connector);
fa7dbd7688849d Thomas Zimmermann 2020-06-17  1212  	struct ast_private *ast = to_ast_private(connector->dev);
312fec1405dd54 Dave Airlie       2012-02-29  1213  	struct edid *edid;
                                                        ^^^^^^^^^^^^^^^^^^
312fec1405dd54 Dave Airlie       2012-02-29  1214  	int ret;
83c6620bae3f14 Dave Airlie       2014-03-28  1215  	bool flags = false;
6c9bd4432b2527 Gregory Williams  2021-07-30  1216  
83c6620bae3f14 Dave Airlie       2014-03-28  1217  	if (ast->tx_chip_type == AST_TX_DP501) {
83c6620bae3f14 Dave Airlie       2014-03-28  1218  		ast->dp501_maxclk = 0xff;
83c6620bae3f14 Dave Airlie       2014-03-28  1219  		edid = kmalloc(128, GFP_KERNEL);
83c6620bae3f14 Dave Airlie       2014-03-28  1220  		if (!edid)
83c6620bae3f14 Dave Airlie       2014-03-28  1221  			return -ENOMEM;
312fec1405dd54 Dave Airlie       2012-02-29  1222  
83c6620bae3f14 Dave Airlie       2014-03-28  1223  		flags = ast_dp501_read_edid(connector->dev, (u8 *)edid);
83c6620bae3f14 Dave Airlie       2014-03-28  1224  		if (flags)
83c6620bae3f14 Dave Airlie       2014-03-28  1225  			ast->dp501_maxclk = ast_get_dp501_max_clk(connector->dev);
83c6620bae3f14 Dave Airlie       2014-03-28  1226  		else
83c6620bae3f14 Dave Airlie       2014-03-28  1227  			kfree(edid);
                                                                        ^^^^^^^^^^^

83c6620bae3f14 Dave Airlie       2014-03-28  1228  	}
75bd8f71712a8a Thomas Zimmermann 2021-12-01  1229  	if (!flags && ast_connector->i2c)

If "flags" is false then "edid" is either freed or uninitialized.  So
if "ast_connector->i2c" also is false then that's going to cause
problems.  Hopefully that part of the condition can just be removed?

	if (!flags)
		edid = drm_get_edid(connector, &ast_connector->i2c->adapter);

312fec1405dd54 Dave Airlie       2012-02-29  1230  		edid = drm_get_edid(connector, &ast_connector->i2c->adapter);
312fec1405dd54 Dave Airlie       2012-02-29 @1231  	if (edid) {
c555f02371c338 Daniel Vetter     2018-07-09 @1232  		drm_connector_update_edid_property(&ast_connector->base, edid);
312fec1405dd54 Dave Airlie       2012-02-29  1233  		ret = drm_add_edid_modes(connector, edid);
993dcb05e47e35 Jani Nikula       2012-08-15  1234  		kfree(edid);
312fec1405dd54 Dave Airlie       2012-02-29  1235  		return ret;
6c9bd4432b2527 Gregory Williams  2021-07-30  1236  	}
c555f02371c338 Daniel Vetter     2018-07-09  1237  	drm_connector_update_edid_property(&ast_connector->base, NULL);
312fec1405dd54 Dave Airlie       2012-02-29  1238  	return 0;
312fec1405dd54 Dave Airlie       2012-02-29  1239  }

---
0-DAY CI Kernel Test Service, Intel Corporation
https://lists.01.org/hyperkitty/list/kbuild-all(a)lists.01.org

Re: [PATCH 1/3] drm/ast: Handle failed I2C initialization gracefully

[Dan Carpenter]

Hi Thomas,

url:    https://github.com/0day-ci/linux/commits/Thomas-Zimmermann/ast-Fix-I2C-corner-cases-wrt-init-cleanup/20211201-233308
base:   6a8f90ec433e2f5de5fc16d7a4839771b7027cc0
config: i386-randconfig-m021-20211203 (https://download.01.org/0day-ci/archive/20211204/202112042126.N4Qr3RiC-lkp@intel.com/config)
compiler: gcc-9 (Debian 9.3.0-22) 9.3.0

If you fix the issue, kindly add following tag as appropriate
Reported-by: kernel test robot <lkp@intel.com>
Reported-by: Dan Carpenter <dan.carpenter@oracle.com>

smatch warnings:
drivers/gpu/drm/ast/ast_mode.c:1231 ast_get_modes() error: uninitialized symbol 'edid'.
drivers/gpu/drm/ast/ast_mode.c:1232 ast_get_modes() warn: passing freed memory 'edid'

vim +/edid +1231 drivers/gpu/drm/ast/ast_mode.c

312fec1405dd54 Dave Airlie       2012-02-29  1209  static int ast_get_modes(struct drm_connector *connector)
312fec1405dd54 Dave Airlie       2012-02-29  1210  {
312fec1405dd54 Dave Airlie       2012-02-29  1211  	struct ast_connector *ast_connector = to_ast_connector(connector);
fa7dbd7688849d Thomas Zimmermann 2020-06-17  1212  	struct ast_private *ast = to_ast_private(connector->dev);
312fec1405dd54 Dave Airlie       2012-02-29  1213  	struct edid *edid;
                                                        ^^^^^^^^^^^^^^^^^^
312fec1405dd54 Dave Airlie       2012-02-29  1214  	int ret;
83c6620bae3f14 Dave Airlie       2014-03-28  1215  	bool flags = false;
6c9bd4432b2527 Gregory Williams  2021-07-30  1216  
83c6620bae3f14 Dave Airlie       2014-03-28  1217  	if (ast->tx_chip_type == AST_TX_DP501) {
83c6620bae3f14 Dave Airlie       2014-03-28  1218  		ast->dp501_maxclk = 0xff;
83c6620bae3f14 Dave Airlie       2014-03-28  1219  		edid = kmalloc(128, GFP_KERNEL);
83c6620bae3f14 Dave Airlie       2014-03-28  1220  		if (!edid)
83c6620bae3f14 Dave Airlie       2014-03-28  1221  			return -ENOMEM;
312fec1405dd54 Dave Airlie       2012-02-29  1222  
83c6620bae3f14 Dave Airlie       2014-03-28  1223  		flags = ast_dp501_read_edid(connector->dev, (u8 *)edid);
83c6620bae3f14 Dave Airlie       2014-03-28  1224  		if (flags)
83c6620bae3f14 Dave Airlie       2014-03-28  1225  			ast->dp501_maxclk = ast_get_dp501_max_clk(connector->dev);
83c6620bae3f14 Dave Airlie       2014-03-28  1226  		else
83c6620bae3f14 Dave Airlie       2014-03-28  1227  			kfree(edid);
                                                                        ^^^^^^^^^^^

83c6620bae3f14 Dave Airlie       2014-03-28  1228  	}
75bd8f71712a8a Thomas Zimmermann 2021-12-01  1229  	if (!flags && ast_connector->i2c)

If "flags" is false then "edid" is either freed or uninitialized.  So
if "ast_connector->i2c" also is false then that's going to cause
problems.  Hopefully that part of the condition can just be removed?

	if (!flags)
		edid = drm_get_edid(connector, &ast_connector->i2c->adapter);

312fec1405dd54 Dave Airlie       2012-02-29  1230  		edid = drm_get_edid(connector, &ast_connector->i2c->adapter);
312fec1405dd54 Dave Airlie       2012-02-29 @1231  	if (edid) {
c555f02371c338 Daniel Vetter     2018-07-09 @1232  		drm_connector_update_edid_property(&ast_connector->base, edid);
312fec1405dd54 Dave Airlie       2012-02-29  1233  		ret = drm_add_edid_modes(connector, edid);
993dcb05e47e35 Jani Nikula       2012-08-15  1234  		kfree(edid);
312fec1405dd54 Dave Airlie       2012-02-29  1235  		return ret;
6c9bd4432b2527 Gregory Williams  2021-07-30  1236  	}
c555f02371c338 Daniel Vetter     2018-07-09  1237  	drm_connector_update_edid_property(&ast_connector->base, NULL);
312fec1405dd54 Dave Airlie       2012-02-29  1238  	return 0;
312fec1405dd54 Dave Airlie       2012-02-29  1239  }

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