[PATCH v2 0/2] drm/imx/dcss: implement region request and devres

[PATCH v2 0/2] drm/imx/dcss: implement region request and devres

[Philipp Stanner]

dcss currently does not request its memory resource. This series adds
that request with devres. As we're at it, it also ports all the ioremaps
and associated allocations to devres.

I can build this, but I don't have the hardware available to test it. So
you might want to have a closer look.

P.

Philipp Stanner (2):
  drm/dcss: request memory region
  drm/imx/dcss: have all init functions use devres

 drivers/gpu/drm/imx/dcss/dcss-blkctl.c | 14 +++-----------
 drivers/gpu/drm/imx/dcss/dcss-ctxld.c  | 15 ++++-----------
 drivers/gpu/drm/imx/dcss/dcss-dev.c    | 18 +++++++++---------
 drivers/gpu/drm/imx/dcss/dcss-dpr.c    | 25 ++++++-------------------
 drivers/gpu/drm/imx/dcss/dcss-drv.c    | 12 +++---------
 drivers/gpu/drm/imx/dcss/dcss-dtg.c    | 23 ++++-------------------
 drivers/gpu/drm/imx/dcss/dcss-scaler.c | 22 ++++------------------
 drivers/gpu/drm/imx/dcss/dcss-ss.c     | 11 +++--------
 8 files changed, 36 insertions(+), 104 deletions(-)

-- 
2.43.0

[PATCH v2 1/2] drm/dcss: request memory region

[Philipp Stanner]

The driver's memory regions are currently just ioremap()ed, but not
reserved through a request. That's not a bug, but having the request is
a little more robust.

Implement the region-request through the corresponding managed
devres-function.

Signed-off-by: Philipp Stanner <pstanner@redhat.com>
---
 drivers/gpu/drm/imx/dcss/dcss-dev.c | 7 +++++++
 1 file changed, 7 insertions(+)

diff --git a/drivers/gpu/drm/imx/dcss/dcss-dev.c b/drivers/gpu/drm/imx/dcss/dcss-dev.c
index 4f3af0dfb344..1f93313c89b7 100644
--- a/drivers/gpu/drm/imx/dcss/dcss-dev.c
+++ b/drivers/gpu/drm/imx/dcss/dcss-dev.c
@@ -170,6 +170,7 @@ struct dcss_dev *dcss_dev_create(struct device *dev, bool hdmi_output)
 	struct resource *res;
 	struct dcss_dev *dcss;
 	const struct dcss_type_data *devtype;
+	resource_size_t res_len;
 
 	devtype = of_device_get_match_data(dev);
 	if (!devtype) {
@@ -183,6 +184,12 @@ struct dcss_dev *dcss_dev_create(struct device *dev, bool hdmi_output)
 		return ERR_PTR(-EINVAL);
 	}
 
+	res_len = res->end - res->start;
+	if (!devm_request_mem_region(pdev->dev, res->start, res_len, "dcss")) {
+		dev_err(dev, "cannot request memory region\n");
+		return ERR_PTR(-EBUSY);
+	}
+
 	dcss = kzalloc(sizeof(*dcss), GFP_KERNEL);
 	if (!dcss)
 		return ERR_PTR(-ENOMEM);
-- 
2.43.0

Re: [PATCH v2 1/2] drm/dcss: request memory region

[kernel test robot]

Hi Philipp,

kernel test robot noticed the following build errors:

[auto build test ERROR on v6.7]
[also build test ERROR on linus/master next-20240109]
[cannot apply to drm-misc/drm-misc-next]
[If your patch is applied to the wrong git tree, kindly drop us a note.
And when submitting patch, we suggest to use '--base' as documented in
https://git-scm.com/docs/git-format-patch#_base_tree_information]

url:    https://github.com/intel-lab-lkp/linux/commits/Philipp-Stanner/drm-dcss-request-memory-region/20240109-182239
base:   v6.7
patch link:    https://lore.kernel.org/r/20240109102032.16165-2-pstanner%40redhat.com
patch subject: [PATCH v2 1/2] drm/dcss: request memory region
config: arm64-defconfig (https://download.01.org/0day-ci/archive/20240110/202401100801.1Wiy3ZEd-lkp@intel.com/config)
compiler: aarch64-linux-gcc (GCC) 13.2.0
reproduce (this is a W=1 build): (https://download.01.org/0day-ci/archive/20240110/202401100801.1Wiy3ZEd-lkp@intel.com/reproduce)

If you fix the issue in a separate patch/commit (i.e. not just a new version of
the same patch/commit), kindly add following tags
| Reported-by: kernel test robot <lkp@intel.com>
| Closes: https://lore.kernel.org/oe-kbuild-all/202401100801.1Wiy3ZEd-lkp@intel.com/

All errors (new ones prefixed by >>):

   In file included from include/linux/device.h:17,
                    from include/linux/platform_device.h:13,
                    from drivers/gpu/drm/imx/dcss/dcss-dev.c:9:
   drivers/gpu/drm/imx/dcss/dcss-dev.c: In function 'dcss_dev_create':
>> drivers/gpu/drm/imx/dcss/dcss-dev.c:188:42: error: incompatible type for argument 1 of '__devm_request_region'
     188 |         if (!devm_request_mem_region(pdev->dev, res->start, res_len, "dcss")) {
         |                                      ~~~~^~~~~
         |                                          |
         |                                          struct device
   include/linux/ioport.h:306:31: note: in definition of macro 'devm_request_mem_region'
     306 |         __devm_request_region(dev, &iomem_resource, (start), (n), (name))
         |                               ^~~
   include/linux/ioport.h:308:63: note: expected 'struct device *' but argument is of type 'struct device'
     308 | extern struct resource * __devm_request_region(struct device *dev,
         |                                                ~~~~~~~~~~~~~~~^~~


vim +/__devm_request_region +188 drivers/gpu/drm/imx/dcss/dcss-dev.c

   165	
   166	struct dcss_dev *dcss_dev_create(struct device *dev, bool hdmi_output)
   167	{
   168		struct platform_device *pdev = to_platform_device(dev);
   169		int ret;
   170		struct resource *res;
   171		struct dcss_dev *dcss;
   172		const struct dcss_type_data *devtype;
   173		resource_size_t res_len;
   174	
   175		devtype = of_device_get_match_data(dev);
   176		if (!devtype) {
   177			dev_err(dev, "no device match found\n");
   178			return ERR_PTR(-ENODEV);
   179		}
   180	
   181		res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
   182		if (!res) {
   183			dev_err(dev, "cannot get memory resource\n");
   184			return ERR_PTR(-EINVAL);
   185		}
   186	
   187		res_len = res->end - res->start;
 > 188		if (!devm_request_mem_region(pdev->dev, res->start, res_len, "dcss")) {
   189			dev_err(dev, "cannot request memory region\n");
   190			return ERR_PTR(-EBUSY);
   191		}
   192	
   193		dcss = kzalloc(sizeof(*dcss), GFP_KERNEL);
   194		if (!dcss)
   195			return ERR_PTR(-ENOMEM);
   196	
   197		dcss->dev = dev;
   198		dcss->devtype = devtype;
   199		dcss->hdmi_output = hdmi_output;
   200	
   201		ret = dcss_clks_init(dcss);
   202		if (ret) {
   203			dev_err(dev, "clocks initialization failed\n");
   204			goto err;
   205		}
   206	
   207		dcss->of_port = of_graph_get_port_by_id(dev->of_node, 0);
   208		if (!dcss->of_port) {
   209			dev_err(dev, "no port@0 node in %pOF\n", dev->of_node);
   210			ret = -ENODEV;
   211			goto clks_err;
   212		}
   213	
   214		dcss->start_addr = res->start;
   215	
   216		ret = dcss_submodules_init(dcss);
   217		if (ret) {
   218			of_node_put(dcss->of_port);
   219			dev_err(dev, "submodules initialization failed\n");
   220			goto clks_err;
   221		}
   222	
   223		init_completion(&dcss->disable_completion);
   224	
   225		pm_runtime_set_autosuspend_delay(dev, 100);
   226		pm_runtime_use_autosuspend(dev);
   227		pm_runtime_set_suspended(dev);
   228		pm_runtime_allow(dev);
   229		pm_runtime_enable(dev);
   230	
   231		return dcss;
   232	
   233	clks_err:
   234		dcss_clks_release(dcss);
   235	
   236	err:
   237		kfree(dcss);
   238	
   239		return ERR_PTR(ret);
   240	}
   241	

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

Re: [PATCH v2 1/2] drm/dcss: request memory region

[kernel test robot]

Hi Philipp,

kernel test robot noticed the following build errors:

[auto build test ERROR on v6.7]
[also build test ERROR on linus/master next-20240109]
[cannot apply to drm-misc/drm-misc-next]
[If your patch is applied to the wrong git tree, kindly drop us a note.
And when submitting patch, we suggest to use '--base' as documented in
https://git-scm.com/docs/git-format-patch#_base_tree_information]

url:    https://github.com/intel-lab-lkp/linux/commits/Philipp-Stanner/drm-dcss-request-memory-region/20240109-182239
base:   v6.7
patch link:    https://lore.kernel.org/r/20240109102032.16165-2-pstanner%40redhat.com
patch subject: [PATCH v2 1/2] drm/dcss: request memory region
config: arm64-allmodconfig (https://download.01.org/0day-ci/archive/20240110/202401101201.yVs3iqFU-lkp@intel.com/config)
compiler: clang version 18.0.0git (https://github.com/llvm/llvm-project 7e186d366d6c7def0543acc255931f617e76dff0)
reproduce (this is a W=1 build): (https://download.01.org/0day-ci/archive/20240110/202401101201.yVs3iqFU-lkp@intel.com/reproduce)

If you fix the issue in a separate patch/commit (i.e. not just a new version of
the same patch/commit), kindly add following tags
| Reported-by: kernel test robot <lkp@intel.com>
| Closes: https://lore.kernel.org/oe-kbuild-all/202401101201.yVs3iqFU-lkp@intel.com/

All errors (new ones prefixed by >>):

>> drivers/gpu/drm/imx/dcss/dcss-dev.c:188:31: error: passing 'struct device' to parameter of incompatible type 'struct device *'; take the address with &
     188 |         if (!devm_request_mem_region(pdev->dev, res->start, res_len, "dcss")) {
         |                                      ^~~~~~~~~
         |                                      &
   include/linux/ioport.h:306:24: note: expanded from macro 'devm_request_mem_region'
     306 |         __devm_request_region(dev, &iomem_resource, (start), (n), (name))
         |                               ^~~
   include/linux/ioport.h:308:63: note: passing argument to parameter 'dev' here
     308 | extern struct resource * __devm_request_region(struct device *dev,
         |                                                               ^
   1 error generated.


vim +188 drivers/gpu/drm/imx/dcss/dcss-dev.c

   165	
   166	struct dcss_dev *dcss_dev_create(struct device *dev, bool hdmi_output)
   167	{
   168		struct platform_device *pdev = to_platform_device(dev);
   169		int ret;
   170		struct resource *res;
   171		struct dcss_dev *dcss;
   172		const struct dcss_type_data *devtype;
   173		resource_size_t res_len;
   174	
   175		devtype = of_device_get_match_data(dev);
   176		if (!devtype) {
   177			dev_err(dev, "no device match found\n");
   178			return ERR_PTR(-ENODEV);
   179		}
   180	
   181		res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
   182		if (!res) {
   183			dev_err(dev, "cannot get memory resource\n");
   184			return ERR_PTR(-EINVAL);
   185		}
   186	
   187		res_len = res->end - res->start;
 > 188		if (!devm_request_mem_region(pdev->dev, res->start, res_len, "dcss")) {
   189			dev_err(dev, "cannot request memory region\n");
   190			return ERR_PTR(-EBUSY);
   191		}
   192	
   193		dcss = kzalloc(sizeof(*dcss), GFP_KERNEL);
   194		if (!dcss)
   195			return ERR_PTR(-ENOMEM);
   196	
   197		dcss->dev = dev;
   198		dcss->devtype = devtype;
   199		dcss->hdmi_output = hdmi_output;
   200	
   201		ret = dcss_clks_init(dcss);
   202		if (ret) {
   203			dev_err(dev, "clocks initialization failed\n");
   204			goto err;
   205		}
   206	
   207		dcss->of_port = of_graph_get_port_by_id(dev->of_node, 0);
   208		if (!dcss->of_port) {
   209			dev_err(dev, "no port@0 node in %pOF\n", dev->of_node);
   210			ret = -ENODEV;
   211			goto clks_err;
   212		}
   213	
   214		dcss->start_addr = res->start;
   215	
   216		ret = dcss_submodules_init(dcss);
   217		if (ret) {
   218			of_node_put(dcss->of_port);
   219			dev_err(dev, "submodules initialization failed\n");
   220			goto clks_err;
   221		}
   222	
   223		init_completion(&dcss->disable_completion);
   224	
   225		pm_runtime_set_autosuspend_delay(dev, 100);
   226		pm_runtime_use_autosuspend(dev);
   227		pm_runtime_set_suspended(dev);
   228		pm_runtime_allow(dev);
   229		pm_runtime_enable(dev);
   230	
   231		return dcss;
   232	
   233	clks_err:
   234		dcss_clks_release(dcss);
   235	
   236	err:
   237		kfree(dcss);
   238	
   239		return ERR_PTR(ret);
   240	}
   241	

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

[PATCH v2 2/2] drm/imx/dcss: have all init functions use devres

[Philipp Stanner]

dcss currently allocates and ioremaps quite a few resources in its probe
function's call graph. Devres now provides convenient functions which
perform the same task but do the cleanup automatically.

Port all memory allocations and ioremap() calls to the devres
counterparts.

Signed-off-by: Philipp Stanner <pstanner@redhat.com>
---
 drivers/gpu/drm/imx/dcss/dcss-blkctl.c | 14 +++-----------
 drivers/gpu/drm/imx/dcss/dcss-ctxld.c  | 15 ++++-----------
 drivers/gpu/drm/imx/dcss/dcss-dev.c    | 11 ++---------
 drivers/gpu/drm/imx/dcss/dcss-dpr.c    | 25 ++++++-------------------
 drivers/gpu/drm/imx/dcss/dcss-drv.c    | 12 +++---------
 drivers/gpu/drm/imx/dcss/dcss-dtg.c    | 23 ++++-------------------
 drivers/gpu/drm/imx/dcss/dcss-scaler.c | 22 ++++------------------
 drivers/gpu/drm/imx/dcss/dcss-ss.c     | 11 +++--------
 8 files changed, 29 insertions(+), 104 deletions(-)

diff --git a/drivers/gpu/drm/imx/dcss/dcss-blkctl.c b/drivers/gpu/drm/imx/dcss/dcss-blkctl.c
index c9b54bb2692d..58e12ec65f80 100644
--- a/drivers/gpu/drm/imx/dcss/dcss-blkctl.c
+++ b/drivers/gpu/drm/imx/dcss/dcss-blkctl.c
@@ -41,15 +41,15 @@ void dcss_blkctl_cfg(struct dcss_blkctl *blkctl)
 int dcss_blkctl_init(struct dcss_dev *dcss, unsigned long blkctl_base)
 {
 	struct dcss_blkctl *blkctl;
+	struct device *dev = dcss->dev;
 
-	blkctl = kzalloc(sizeof(*blkctl), GFP_KERNEL);
+	blkctl = devm_kzalloc(dev, sizeof(*blkctl), GFP_KERNEL);
 	if (!blkctl)
 		return -ENOMEM;
 
-	blkctl->base_reg = ioremap(blkctl_base, SZ_4K);
+	blkctl->base_reg = devm_ioremap(dev, blkctl_base, SZ_4K);
 	if (!blkctl->base_reg) {
 		dev_err(dcss->dev, "unable to remap BLK CTRL base\n");
-		kfree(blkctl);
 		return -ENOMEM;
 	}
 
@@ -60,11 +60,3 @@ int dcss_blkctl_init(struct dcss_dev *dcss, unsigned long blkctl_base)
 
 	return 0;
 }
-
-void dcss_blkctl_exit(struct dcss_blkctl *blkctl)
-{
-	if (blkctl->base_reg)
-		iounmap(blkctl->base_reg);
-
-	kfree(blkctl);
-}
diff --git a/drivers/gpu/drm/imx/dcss/dcss-ctxld.c b/drivers/gpu/drm/imx/dcss/dcss-ctxld.c
index 3a84cb3209c4..444511d0f382 100644
--- a/drivers/gpu/drm/imx/dcss/dcss-ctxld.c
+++ b/drivers/gpu/drm/imx/dcss/dcss-ctxld.c
@@ -199,10 +199,11 @@ static int dcss_ctxld_alloc_ctx(struct dcss_ctxld *ctxld)
 
 int dcss_ctxld_init(struct dcss_dev *dcss, unsigned long ctxld_base)
 {
+	struct device *dev = dcss->dev;
 	struct dcss_ctxld *ctxld;
 	int ret;
 
-	ctxld = kzalloc(sizeof(*ctxld), GFP_KERNEL);
+	ctxld = devm_kzalloc(dev, sizeof(*ctxld), GFP_KERNEL);
 	if (!ctxld)
 		return -ENOMEM;
 
@@ -217,7 +218,7 @@ int dcss_ctxld_init(struct dcss_dev *dcss, unsigned long ctxld_base)
 		goto err;
 	}
 
-	ctxld->ctxld_reg = ioremap(ctxld_base, SZ_4K);
+	ctxld->ctxld_reg = devm_ioremap(dev, ctxld_base, SZ_4K);
 	if (!ctxld->ctxld_reg) {
 		dev_err(dcss->dev, "ctxld: unable to remap ctxld base\n");
 		ret = -ENOMEM;
@@ -226,18 +227,14 @@ int dcss_ctxld_init(struct dcss_dev *dcss, unsigned long ctxld_base)
 
 	ret = dcss_ctxld_irq_config(ctxld, to_platform_device(dcss->dev));
 	if (ret)
-		goto err_irq;
+		goto err;
 
 	dcss_ctxld_hw_cfg(ctxld);
 
 	return 0;
 
-err_irq:
-	iounmap(ctxld->ctxld_reg);
-
 err:
 	dcss_ctxld_free_ctx(ctxld);
-	kfree(ctxld);
 
 	return ret;
 }
@@ -246,11 +243,7 @@ void dcss_ctxld_exit(struct dcss_ctxld *ctxld)
 {
 	free_irq(ctxld->irq, ctxld);
 
-	if (ctxld->ctxld_reg)
-		iounmap(ctxld->ctxld_reg);
-
 	dcss_ctxld_free_ctx(ctxld);
-	kfree(ctxld);
 }
 
 static int dcss_ctxld_enable_locked(struct dcss_ctxld *ctxld)
diff --git a/drivers/gpu/drm/imx/dcss/dcss-dev.c b/drivers/gpu/drm/imx/dcss/dcss-dev.c
index 1f93313c89b7..206452cf98d6 100644
--- a/drivers/gpu/drm/imx/dcss/dcss-dev.c
+++ b/drivers/gpu/drm/imx/dcss/dcss-dev.c
@@ -109,8 +109,6 @@ static int dcss_submodules_init(struct dcss_dev *dcss)
 	dcss_ctxld_exit(dcss->ctxld);
 
 ctxld_err:
-	dcss_blkctl_exit(dcss->blkctl);
-
 	dcss_clocks_disable(dcss);
 
 	return ret;
@@ -190,7 +188,7 @@ struct dcss_dev *dcss_dev_create(struct device *dev, bool hdmi_output)
 		return ERR_PTR(-EBUSY);
 	}
 
-	dcss = kzalloc(sizeof(*dcss), GFP_KERNEL);
+	dcss = devm_kzalloc(dev, sizeof(*dcss), GFP_KERNEL);
 	if (!dcss)
 		return ERR_PTR(-ENOMEM);
 
@@ -201,7 +199,7 @@ struct dcss_dev *dcss_dev_create(struct device *dev, bool hdmi_output)
 	ret = dcss_clks_init(dcss);
 	if (ret) {
 		dev_err(dev, "clocks initialization failed\n");
-		goto err;
+		return ret;
 	}
 
 	dcss->of_port = of_graph_get_port_by_id(dev->of_node, 0);
@@ -233,9 +231,6 @@ struct dcss_dev *dcss_dev_create(struct device *dev, bool hdmi_output)
 clks_err:
 	dcss_clks_release(dcss);
 
-err:
-	kfree(dcss);
-
 	return ERR_PTR(ret);
 }
 
@@ -253,8 +248,6 @@ void dcss_dev_destroy(struct dcss_dev *dcss)
 	dcss_submodules_stop(dcss);
 
 	dcss_clks_release(dcss);
-
-	kfree(dcss);
 }
 
 static int dcss_dev_suspend(struct device *dev)
diff --git a/drivers/gpu/drm/imx/dcss/dcss-dpr.c b/drivers/gpu/drm/imx/dcss/dcss-dpr.c
index df9dab949bf2..d6b2ad5e6977 100644
--- a/drivers/gpu/drm/imx/dcss/dcss-dpr.c
+++ b/drivers/gpu/drm/imx/dcss/dcss-dpr.c
@@ -125,7 +125,8 @@ static void dcss_dpr_write(struct dcss_dpr_ch *ch, u32 val, u32 ofs)
 	dcss_ctxld_write(dpr->ctxld, dpr->ctx_id, val, ch->base_ofs + ofs);
 }
 
-static int dcss_dpr_ch_init_all(struct dcss_dpr *dpr, unsigned long dpr_base)
+static int dcss_dpr_ch_init_all(struct device *dev, struct dcss_dpr *dpr,
+		unsigned long dpr_base)
 {
 	struct dcss_dpr_ch *ch;
 	int i;
@@ -135,7 +136,7 @@ static int dcss_dpr_ch_init_all(struct dcss_dpr *dpr, unsigned long dpr_base)
 
 		ch->base_ofs = dpr_base + i * 0x1000;
 
-		ch->base_reg = ioremap(ch->base_ofs, SZ_4K);
+		ch->base_reg = devm_ioremap(dev, ch->base_ofs, SZ_4K);
 		if (!ch->base_reg) {
 			dev_err(dpr->dev, "dpr: unable to remap ch %d base\n",
 				i);
@@ -154,8 +155,9 @@ static int dcss_dpr_ch_init_all(struct dcss_dpr *dpr, unsigned long dpr_base)
 int dcss_dpr_init(struct dcss_dev *dcss, unsigned long dpr_base)
 {
 	struct dcss_dpr *dpr;
+	struct device *dev = dcss->dev;
 
-	dpr = kzalloc(sizeof(*dpr), GFP_KERNEL);
+	dpr = devm_kzalloc(dev, sizeof(*dpr), GFP_KERNEL);
 	if (!dpr)
 		return -ENOMEM;
 
@@ -164,18 +166,8 @@ int dcss_dpr_init(struct dcss_dev *dcss, unsigned long dpr_base)
 	dpr->ctxld = dcss->ctxld;
 	dpr->ctx_id = CTX_SB_HP;
 
-	if (dcss_dpr_ch_init_all(dpr, dpr_base)) {
-		int i;
-
-		for (i = 0; i < 3; i++) {
-			if (dpr->ch[i].base_reg)
-				iounmap(dpr->ch[i].base_reg);
-		}
-
-		kfree(dpr);
-
+	if (dcss_dpr_ch_init_all(dev, dpr, dpr_base))
 		return -ENOMEM;
-	}
 
 	return 0;
 }
@@ -189,12 +181,7 @@ void dcss_dpr_exit(struct dcss_dpr *dpr)
 		struct dcss_dpr_ch *ch = &dpr->ch[ch_no];
 
 		dcss_writel(0, ch->base_reg + DCSS_DPR_SYSTEM_CTRL0);
-
-		if (ch->base_reg)
-			iounmap(ch->base_reg);
 	}
-
-	kfree(dpr);
 }
 
 static u32 dcss_dpr_x_pix_wide_adjust(struct dcss_dpr_ch *ch, u32 pix_wide,
diff --git a/drivers/gpu/drm/imx/dcss/dcss-drv.c b/drivers/gpu/drm/imx/dcss/dcss-drv.c
index b61cec0cc79d..bd3f9d58042c 100644
--- a/drivers/gpu/drm/imx/dcss/dcss-drv.c
+++ b/drivers/gpu/drm/imx/dcss/dcss-drv.c
@@ -51,15 +51,13 @@ static int dcss_drv_platform_probe(struct platform_device *pdev)
 
 	of_node_put(remote);
 
-	mdrv = kzalloc(sizeof(*mdrv), GFP_KERNEL);
+	mdrv = devm_kzalloc(dev, sizeof(*mdrv), GFP_KERNEL);
 	if (!mdrv)
 		return -ENOMEM;
 
 	mdrv->dcss = dcss_dev_create(dev, hdmi_output);
-	if (IS_ERR(mdrv->dcss)) {
-		err = PTR_ERR(mdrv->dcss);
-		goto err;
-	}
+	if (IS_ERR(mdrv->dcss))
+		return PTR_ERR(mdrv->dcss);
 
 	dev_set_drvdata(dev, mdrv);
 
@@ -75,8 +73,6 @@ static int dcss_drv_platform_probe(struct platform_device *pdev)
 dcss_shutoff:
 	dcss_dev_destroy(mdrv->dcss);
 
-err:
-	kfree(mdrv);
 	return err;
 }
 
@@ -87,8 +83,6 @@ static int dcss_drv_platform_remove(struct platform_device *pdev)
 	dcss_kms_detach(mdrv->kms);
 	dcss_dev_destroy(mdrv->dcss);
 
-	kfree(mdrv);
-
 	return 0;
 }
 
diff --git a/drivers/gpu/drm/imx/dcss/dcss-dtg.c b/drivers/gpu/drm/imx/dcss/dcss-dtg.c
index 30de00540f63..5c0f697587e6 100644
--- a/drivers/gpu/drm/imx/dcss/dcss-dtg.c
+++ b/drivers/gpu/drm/imx/dcss/dcss-dtg.c
@@ -151,8 +151,9 @@ int dcss_dtg_init(struct dcss_dev *dcss, unsigned long dtg_base)
 {
 	int ret = 0;
 	struct dcss_dtg *dtg;
+	struct device *dev = dcss->dev;
 
-	dtg = kzalloc(sizeof(*dtg), GFP_KERNEL);
+	dtg = devm_kzalloc(dev, sizeof(*dtg), GFP_KERNEL);
 	if (!dtg)
 		return -ENOMEM;
 
@@ -160,11 +161,10 @@ int dcss_dtg_init(struct dcss_dev *dcss, unsigned long dtg_base)
 	dtg->dev = dcss->dev;
 	dtg->ctxld = dcss->ctxld;
 
-	dtg->base_reg = ioremap(dtg_base, SZ_4K);
+	dtg->base_reg = devm_ioremap(dev, dtg_base, SZ_4K);
 	if (!dtg->base_reg) {
 		dev_err(dcss->dev, "dtg: unable to remap dtg base\n");
-		ret = -ENOMEM;
-		goto err_ioremap;
+		return -ENOMEM;
 	}
 
 	dtg->base_ofs = dtg_base;
@@ -176,16 +176,6 @@ int dcss_dtg_init(struct dcss_dev *dcss, unsigned long dtg_base)
 		((dtg->alpha << DEFAULT_FG_ALPHA_POS) & DEFAULT_FG_ALPHA_MASK);
 
 	ret = dcss_dtg_irq_config(dtg, to_platform_device(dcss->dev));
-	if (ret)
-		goto err_irq;
-
-	return 0;
-
-err_irq:
-	iounmap(dtg->base_reg);
-
-err_ioremap:
-	kfree(dtg);
 
 	return ret;
 }
@@ -193,11 +183,6 @@ int dcss_dtg_init(struct dcss_dev *dcss, unsigned long dtg_base)
 void dcss_dtg_exit(struct dcss_dtg *dtg)
 {
 	free_irq(dtg->ctxld_kick_irq, dtg);
-
-	if (dtg->base_reg)
-		iounmap(dtg->base_reg);
-
-	kfree(dtg);
 }
 
 void dcss_dtg_sync_set(struct dcss_dtg *dtg, struct videomode *vm)
diff --git a/drivers/gpu/drm/imx/dcss/dcss-scaler.c b/drivers/gpu/drm/imx/dcss/dcss-scaler.c
index 47852b9dd5ea..3dbd0ed68ac1 100644
--- a/drivers/gpu/drm/imx/dcss/dcss-scaler.c
+++ b/drivers/gpu/drm/imx/dcss/dcss-scaler.c
@@ -302,7 +302,7 @@ static int dcss_scaler_ch_init_all(struct dcss_scaler *scl,
 
 		ch->base_ofs = scaler_base + i * 0x400;
 
-		ch->base_reg = ioremap(ch->base_ofs, SZ_4K);
+		ch->base_reg = devm_ioremap(dev, ch->base_ofs, SZ_4K);
 		if (!ch->base_reg) {
 			dev_err(scl->dev, "scaler: unable to remap ch base\n");
 			return -ENOMEM;
@@ -317,8 +317,9 @@ static int dcss_scaler_ch_init_all(struct dcss_scaler *scl,
 int dcss_scaler_init(struct dcss_dev *dcss, unsigned long scaler_base)
 {
 	struct dcss_scaler *scaler;
+	struct device *dev = dcss->dev;
 
-	scaler = kzalloc(sizeof(*scaler), GFP_KERNEL);
+	scaler = devm_kzalloc(dev, sizeof(*scaler), GFP_KERNEL);
 	if (!scaler)
 		return -ENOMEM;
 
@@ -327,18 +328,8 @@ int dcss_scaler_init(struct dcss_dev *dcss, unsigned long scaler_base)
 	scaler->ctxld = dcss->ctxld;
 	scaler->ctx_id = CTX_SB_HP;
 
-	if (dcss_scaler_ch_init_all(scaler, scaler_base)) {
-		int i;
-
-		for (i = 0; i < 3; i++) {
-			if (scaler->ch[i].base_reg)
-				iounmap(scaler->ch[i].base_reg);
-		}
-
-		kfree(scaler);
-
+	if (dcss_scaler_ch_init_all(dev, scaler, scaler_base))
 		return -ENOMEM;
-	}
 
 	return 0;
 }
@@ -351,12 +342,7 @@ void dcss_scaler_exit(struct dcss_scaler *scl)
 		struct dcss_scaler_ch *ch = &scl->ch[ch_no];
 
 		dcss_writel(0, ch->base_reg + DCSS_SCALER_CTRL);
-
-		if (ch->base_reg)
-			iounmap(ch->base_reg);
 	}
-
-	kfree(scl);
 }
 
 void dcss_scaler_ch_enable(struct dcss_scaler *scl, int ch_num, bool en)
diff --git a/drivers/gpu/drm/imx/dcss/dcss-ss.c b/drivers/gpu/drm/imx/dcss/dcss-ss.c
index 8ddf08da911b..0a8320adc302 100644
--- a/drivers/gpu/drm/imx/dcss/dcss-ss.c
+++ b/drivers/gpu/drm/imx/dcss/dcss-ss.c
@@ -82,8 +82,9 @@ static void dcss_ss_write(struct dcss_ss *ss, u32 val, u32 ofs)
 int dcss_ss_init(struct dcss_dev *dcss, unsigned long ss_base)
 {
 	struct dcss_ss *ss;
+	struct device *dev = dcss->dev;
 
-	ss = kzalloc(sizeof(*ss), GFP_KERNEL);
+	ss = devm_kzalloc(dev, sizeof(*ss), GFP_KERNEL);
 	if (!ss)
 		return -ENOMEM;
 
@@ -91,10 +92,9 @@ int dcss_ss_init(struct dcss_dev *dcss, unsigned long ss_base)
 	ss->dev = dcss->dev;
 	ss->ctxld = dcss->ctxld;
 
-	ss->base_reg = ioremap(ss_base, SZ_4K);
+	ss->base_reg = devm_ioremap(dev, ss_base, SZ_4K);
 	if (!ss->base_reg) {
 		dev_err(dcss->dev, "ss: unable to remap ss base\n");
-		kfree(ss);
 		return -ENOMEM;
 	}
 
@@ -108,11 +108,6 @@ void dcss_ss_exit(struct dcss_ss *ss)
 {
 	/* stop SS */
 	dcss_writel(0, ss->base_reg + DCSS_SS_SYS_CTRL);
-
-	if (ss->base_reg)
-		iounmap(ss->base_reg);
-
-	kfree(ss);
 }
 
 void dcss_ss_subsam_set(struct dcss_ss *ss)
-- 
2.43.0

Re: [PATCH v2 2/2] drm/imx/dcss: have all init functions use devres

[kernel test robot]

Hi Philipp,

kernel test robot noticed the following build errors:

[auto build test ERROR on v6.7]
[also build test ERROR on linus/master]
[cannot apply to drm-misc/drm-misc-next next-20240109]
[If your patch is applied to the wrong git tree, kindly drop us a note.
And when submitting patch, we suggest to use '--base' as documented in
https://git-scm.com/docs/git-format-patch#_base_tree_information]

url:    https://github.com/intel-lab-lkp/linux/commits/Philipp-Stanner/drm-dcss-request-memory-region/20240109-182239
base:   v6.7
patch link:    https://lore.kernel.org/r/20240109102032.16165-3-pstanner%40redhat.com
patch subject: [PATCH v2 2/2] drm/imx/dcss: have all init functions use devres
config: arm64-defconfig (https://download.01.org/0day-ci/archive/20240110/202401101401.bi7U74fr-lkp@intel.com/config)
compiler: aarch64-linux-gcc (GCC) 13.2.0
reproduce (this is a W=1 build): (https://download.01.org/0day-ci/archive/20240110/202401101401.bi7U74fr-lkp@intel.com/reproduce)

If you fix the issue in a separate patch/commit (i.e. not just a new version of
the same patch/commit), kindly add following tags
| Reported-by: kernel test robot <lkp@intel.com>
| Closes: https://lore.kernel.org/oe-kbuild-all/202401101401.bi7U74fr-lkp@intel.com/

All error/warnings (new ones prefixed by >>):

   In file included from include/linux/device.h:17,
                    from include/linux/platform_device.h:13,
                    from drivers/gpu/drm/imx/dcss/dcss-dev.c:9:
   drivers/gpu/drm/imx/dcss/dcss-dev.c: In function 'dcss_dev_create':
   drivers/gpu/drm/imx/dcss/dcss-dev.c:186:42: error: incompatible type for argument 1 of '__devm_request_region'
     186 |         if (!devm_request_mem_region(pdev->dev, res->start, res_len, "dcss")) {
         |                                      ~~~~^~~~~
         |                                          |
         |                                          struct device
   include/linux/ioport.h:306:31: note: in definition of macro 'devm_request_mem_region'
     306 |         __devm_request_region(dev, &iomem_resource, (start), (n), (name))
         |                               ^~~
   include/linux/ioport.h:308:63: note: expected 'struct device *' but argument is of type 'struct device'
     308 | extern struct resource * __devm_request_region(struct device *dev,
         |                                                ~~~~~~~~~~~~~~~^~~
>> drivers/gpu/drm/imx/dcss/dcss-dev.c:202:24: warning: returning 'int' from a function with return type 'struct dcss_dev *' makes pointer from integer without a cast [-Wint-conversion]
     202 |                 return ret;
         |                        ^~~
--
   drivers/gpu/drm/imx/dcss/dcss-scaler.c: In function 'dcss_scaler_ch_init_all':
>> drivers/gpu/drm/imx/dcss/dcss-scaler.c:305:45: error: 'dev' undeclared (first use in this function); did you mean 'cdev'?
     305 |                 ch->base_reg = devm_ioremap(dev, ch->base_ofs, SZ_4K);
         |                                             ^~~
         |                                             cdev
   drivers/gpu/drm/imx/dcss/dcss-scaler.c:305:45: note: each undeclared identifier is reported only once for each function it appears in
   drivers/gpu/drm/imx/dcss/dcss-scaler.c: In function 'dcss_scaler_init':
>> drivers/gpu/drm/imx/dcss/dcss-scaler.c:331:37: error: passing argument 1 of 'dcss_scaler_ch_init_all' from incompatible pointer type [-Werror=incompatible-pointer-types]
     331 |         if (dcss_scaler_ch_init_all(dev, scaler, scaler_base))
         |                                     ^~~
         |                                     |
         |                                     struct device *
   drivers/gpu/drm/imx/dcss/dcss-scaler.c:294:56: note: expected 'struct dcss_scaler *' but argument is of type 'struct device *'
     294 | static int dcss_scaler_ch_init_all(struct dcss_scaler *scl,
         |                                    ~~~~~~~~~~~~~~~~~~~~^~~
>> drivers/gpu/drm/imx/dcss/dcss-scaler.c:331:42: warning: passing argument 2 of 'dcss_scaler_ch_init_all' makes integer from pointer without a cast [-Wint-conversion]
     331 |         if (dcss_scaler_ch_init_all(dev, scaler, scaler_base))
         |                                          ^~~~~~
         |                                          |
         |                                          struct dcss_scaler *
   drivers/gpu/drm/imx/dcss/dcss-scaler.c:295:50: note: expected 'long unsigned int' but argument is of type 'struct dcss_scaler *'
     295 |                                    unsigned long scaler_base)
         |                                    ~~~~~~~~~~~~~~^~~~~~~~~~~
>> drivers/gpu/drm/imx/dcss/dcss-scaler.c:331:13: error: too many arguments to function 'dcss_scaler_ch_init_all'
     331 |         if (dcss_scaler_ch_init_all(dev, scaler, scaler_base))
         |             ^~~~~~~~~~~~~~~~~~~~~~~
   drivers/gpu/drm/imx/dcss/dcss-scaler.c:294:12: note: declared here
     294 | static int dcss_scaler_ch_init_all(struct dcss_scaler *scl,
         |            ^~~~~~~~~~~~~~~~~~~~~~~
   cc1: some warnings being treated as errors


vim +305 drivers/gpu/drm/imx/dcss/dcss-scaler.c

   293	
   294	static int dcss_scaler_ch_init_all(struct dcss_scaler *scl,
   295					   unsigned long scaler_base)
   296	{
   297		struct dcss_scaler_ch *ch;
   298		int i;
   299	
   300		for (i = 0; i < 3; i++) {
   301			ch = &scl->ch[i];
   302	
   303			ch->base_ofs = scaler_base + i * 0x400;
   304	
 > 305			ch->base_reg = devm_ioremap(dev, ch->base_ofs, SZ_4K);
   306			if (!ch->base_reg) {
   307				dev_err(scl->dev, "scaler: unable to remap ch base\n");
   308				return -ENOMEM;
   309			}
   310	
   311			ch->scl = scl;
   312		}
   313	
   314		return 0;
   315	}
   316	
   317	int dcss_scaler_init(struct dcss_dev *dcss, unsigned long scaler_base)
   318	{
   319		struct dcss_scaler *scaler;
   320		struct device *dev = dcss->dev;
   321	
   322		scaler = devm_kzalloc(dev, sizeof(*scaler), GFP_KERNEL);
   323		if (!scaler)
   324			return -ENOMEM;
   325	
   326		dcss->scaler = scaler;
   327		scaler->dev = dcss->dev;
   328		scaler->ctxld = dcss->ctxld;
   329		scaler->ctx_id = CTX_SB_HP;
   330	
 > 331		if (dcss_scaler_ch_init_all(dev, scaler, scaler_base))
   332			return -ENOMEM;
   333	
   334		return 0;
   335	}
   336	

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