diff mbox series

[V6,1/4] drm: of: Add drm_of_get_dsi_bus helper function

Message ID 20221215185211.1560736-2-macroalpha82@gmail.com (mailing list archive)
State New, archived
Headers show
Series drm/panel: Add Magnachip D53E6EA8966 Panel Controller | expand

Commit Message

Chris Morgan Dec. 15, 2022, 6:52 p.m. UTC 
From: Chris Morgan <macromorgan@hotmail.com>

Add helper function to find DSI host for devices where DSI panel is not
a minor of a DSI bus (such as the Samsung AMS495QA01 panel or the
official Raspberry Pi touchscreen display).

Signed-off-by: Chris Morgan <macromorgan@hotmail.com>
Signed-off-by: Maya Matuszczyk <maccraft123mc@gmail.com>
Reviewed-by: Linus Walleij <linus.walleij@linaro.org>
---
 drivers/gpu/drm/drm_of.c | 62 ++++++++++++++++++++++++++++++++++++++++
 include/drm/drm_of.h     | 11 +++++++
 2 files changed, 73 insertions(+)

Comments

kernel test robot Dec. 15, 2022, 10:11 p.m. UTC | #1 
Hi Chris,

Thank you for the patch! Yet something to improve:

[auto build test ERROR on next-20221215]
[also build test ERROR on linus/master v6.1]
[cannot apply to drm-misc/drm-misc-next drm/drm-next drm-intel/for-linux-next drm-intel/for-linux-next-fixes drm-tip/drm-tip drm-exynos/exynos-drm-next v6.1 v6.1-rc8 v6.1-rc7]
[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/Chris-Morgan/drm-panel-Add-Magnachip-D53E6EA8966-Panel-Controller/20221216-025402
patch link:    https://lore.kernel.org/r/20221215185211.1560736-2-macroalpha82%40gmail.com
patch subject: [PATCH V6 1/4] drm: of: Add drm_of_get_dsi_bus helper function
config: hexagon-randconfig-r041-20221215
compiler: clang version 16.0.0 (https://github.com/llvm/llvm-project 98b13979fb05f3ed288a900deb843e7b27589e58)
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/344107cc66e8043fc936e9bc818c38edbe225f6b
        git remote add linux-review https://github.com/intel-lab-lkp/linux
        git fetch --no-tags linux-review Chris-Morgan/drm-panel-Add-Magnachip-D53E6EA8966-Panel-Controller/20221216-025402
        git checkout 344107cc66e8043fc936e9bc818c38edbe225f6b
        # 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=hexagon SHELL=/bin/bash drivers/gpu/drm/etnaviv/

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

All errors (new ones prefixed by >>):

   In file included from drivers/gpu/drm/etnaviv/etnaviv_drv.c:7:
   In file included from include/linux/dma-mapping.h:10:
   In file included from include/linux/scatterlist.h:9:
   In file included from arch/hexagon/include/asm/io.h:334:
   include/asm-generic/io.h:547:31: warning: performing pointer arithmetic on a null pointer has undefined behavior [-Wnull-pointer-arithmetic]
           val = __raw_readb(PCI_IOBASE + addr);
                             ~~~~~~~~~~ ^
   include/asm-generic/io.h:560:61: warning: performing pointer arithmetic on a null pointer has undefined behavior [-Wnull-pointer-arithmetic]
           val = __le16_to_cpu((__le16 __force)__raw_readw(PCI_IOBASE + addr));
                                                           ~~~~~~~~~~ ^
   include/uapi/linux/byteorder/little_endian.h:37:51: note: expanded from macro '__le16_to_cpu'
   #define __le16_to_cpu(x) ((__force __u16)(__le16)(x))
                                                     ^
   In file included from drivers/gpu/drm/etnaviv/etnaviv_drv.c:7:
   In file included from include/linux/dma-mapping.h:10:
   In file included from include/linux/scatterlist.h:9:
   In file included from arch/hexagon/include/asm/io.h:334:
   include/asm-generic/io.h:573:61: warning: performing pointer arithmetic on a null pointer has undefined behavior [-Wnull-pointer-arithmetic]
           val = __le32_to_cpu((__le32 __force)__raw_readl(PCI_IOBASE + addr));
                                                           ~~~~~~~~~~ ^
   include/uapi/linux/byteorder/little_endian.h:35:51: note: expanded from macro '__le32_to_cpu'
   #define __le32_to_cpu(x) ((__force __u32)(__le32)(x))
                                                     ^
   In file included from drivers/gpu/drm/etnaviv/etnaviv_drv.c:7:
   In file included from include/linux/dma-mapping.h:10:
   In file included from include/linux/scatterlist.h:9:
   In file included from arch/hexagon/include/asm/io.h:334:
   include/asm-generic/io.h:584:33: warning: performing pointer arithmetic on a null pointer has undefined behavior [-Wnull-pointer-arithmetic]
           __raw_writeb(value, PCI_IOBASE + addr);
                               ~~~~~~~~~~ ^
   include/asm-generic/io.h:594:59: warning: performing pointer arithmetic on a null pointer has undefined behavior [-Wnull-pointer-arithmetic]
           __raw_writew((u16 __force)cpu_to_le16(value), PCI_IOBASE + addr);
                                                         ~~~~~~~~~~ ^
   include/asm-generic/io.h:604:59: warning: performing pointer arithmetic on a null pointer has undefined behavior [-Wnull-pointer-arithmetic]
           __raw_writel((u32 __force)cpu_to_le32(value), PCI_IOBASE + addr);
                                                         ~~~~~~~~~~ ^
   In file included from drivers/gpu/drm/etnaviv/etnaviv_drv.c:16:
>> include/drm/drm_of.h:138:1: error: expected identifier or '('
   {
   ^
   6 warnings and 1 error generated.


vim +138 include/drm/drm_of.h

   126	
   127	static inline int
   128	drm_of_get_data_lanes_count_ep(const struct device_node *port,
   129				       int port_reg, int reg,
   130				       const unsigned int min,
   131				       const unsigned int max)
   132	{
   133		return -EINVAL;
   134	}
   135	static int drm_of_get_dsi_bus(struct device *dev,
   136				      struct mipi_dsi_host **dsi_host,
   137				      struct mipi_dsi_device_info *info);
 > 138	{
   139		return -EINVAL;
   140	}
   141	#endif
   142
kernel test robot Dec. 15, 2022, 10:11 p.m. UTC | #2 
Hi Chris,

Thank you for the patch! Yet something to improve:

[auto build test ERROR on next-20221215]
[also build test ERROR on linus/master v6.1]
[cannot apply to drm-misc/drm-misc-next drm/drm-next drm-intel/for-linux-next drm-intel/for-linux-next-fixes drm-tip/drm-tip drm-exynos/exynos-drm-next v6.1 v6.1-rc8 v6.1-rc7]
[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/Chris-Morgan/drm-panel-Add-Magnachip-D53E6EA8966-Panel-Controller/20221216-025402
patch link:    https://lore.kernel.org/r/20221215185211.1560736-2-macroalpha82%40gmail.com
patch subject: [PATCH V6 1/4] drm: of: Add drm_of_get_dsi_bus helper function
config: parisc-randconfig-r015-20221215
compiler: hppa-linux-gcc (GCC) 12.1.0
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/344107cc66e8043fc936e9bc818c38edbe225f6b
        git remote add linux-review https://github.com/intel-lab-lkp/linux
        git fetch --no-tags linux-review Chris-Morgan/drm-panel-Add-Magnachip-D53E6EA8966-Panel-Controller/20221216-025402
        git checkout 344107cc66e8043fc936e9bc818c38edbe225f6b
        # save the config file
        mkdir build_dir && cp config build_dir/.config
        COMPILER_INSTALL_PATH=$HOME/0day COMPILER=gcc-12.1.0 make.cross W=1 O=build_dir ARCH=parisc SHELL=/bin/bash drivers/gpu/drm/imx/

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

All errors (new ones prefixed by >>):

   In file included from drivers/gpu/drm/imx/imx-drm-core.c:23:
>> include/drm/drm_of.h:138:1: error: expected identifier or '(' before '{' token
     138 | {
         | ^
   include/drm/drm_of.h:135:12: warning: 'drm_of_get_dsi_bus' declared 'static' but never defined [-Wunused-function]
     135 | static int drm_of_get_dsi_bus(struct device *dev,
         |            ^~~~~~~~~~~~~~~~~~


vim +138 include/drm/drm_of.h

   126	
   127	static inline int
   128	drm_of_get_data_lanes_count_ep(const struct device_node *port,
   129				       int port_reg, int reg,
   130				       const unsigned int min,
   131				       const unsigned int max)
   132	{
   133		return -EINVAL;
   134	}
   135	static int drm_of_get_dsi_bus(struct device *dev,
   136				      struct mipi_dsi_host **dsi_host,
   137				      struct mipi_dsi_device_info *info);
 > 138	{
   139		return -EINVAL;
   140	}
   141	#endif
   142
Linus Walleij Dec. 29, 2022, 9:12 p.m. UTC | #3 
On Thu, Dec 15, 2022 at 7:52 PM Chris Morgan <macroalpha82@gmail.com> wrote:

> From: Chris Morgan <macromorgan@hotmail.com>
>
> Add helper function to find DSI host for devices where DSI panel is not
> a minor of a DSI bus (such as the Samsung AMS495QA01 panel or the
> official Raspberry Pi touchscreen display).
>
> Signed-off-by: Chris Morgan <macromorgan@hotmail.com>
> Signed-off-by: Maya Matuszczyk <maccraft123mc@gmail.com>
> Reviewed-by: Linus Walleij <linus.walleij@linaro.org>

The kernel test robot is complaining because the stub isn't compiling,
because of a copy-paste error (superfluous semicolon).

If you fix this up and resend I think we are ready with the patches!

Yours,
Linus Walleij
diff mbox series

Patch

diff --git a/drivers/gpu/drm/drm_of.c b/drivers/gpu/drm/drm_of.c
index 7bbcb999bb75..7d89ac164069 100644
--- a/drivers/gpu/drm/drm_of.c
+++ b/drivers/gpu/drm/drm_of.c
@@ -10,6 +10,7 @@ 
 #include <drm/drm_crtc.h>
 #include <drm/drm_device.h>
 #include <drm/drm_encoder.h>
+#include <drm/drm_mipi_dsi.h>
 #include <drm/drm_of.h>
 #include <drm/drm_panel.h>
 
@@ -493,3 +494,64 @@  int drm_of_get_data_lanes_count_ep(const struct device_node *port,
 	return ret;
 }
 EXPORT_SYMBOL_GPL(drm_of_get_data_lanes_count_ep);
+
+/**
+ * drm_of_get_dsi_bus - find the DSI bus for a given device
+ * @dev: parent device of display (SPI, I2C)
+ * @dsi_host: DSI host to be populated
+ * @info: DSI device info to be updated with correct DSI node
+ *
+ * Given a panel device parented to a non-DSI device, follow the
+ * devicetree to find the correct DSI host node and populate the
+ * dsi_host with the correct host and info with the correct node.
+ * Returns zero if successful, -EPROBE_DEFER if the DSI host is
+ * found but not available, or -ENODEV otherwise.
+ */
+int drm_of_get_dsi_bus(struct device *dev,
+			      struct mipi_dsi_host **dsi_host,
+			      struct mipi_dsi_device_info *info)
+{
+	struct device_node *endpoint, *dsi_host_node;
+
+	/*
+	 * Get first endpoint child from device.
+	 */
+	endpoint = of_graph_get_next_endpoint(dev->of_node, NULL);
+	if (!endpoint)
+		return -ENODEV;
+
+	/*
+	 * Follow the first endpoint to get the DSI host node.
+	 */
+	dsi_host_node = of_graph_get_remote_port_parent(endpoint);
+	if (!dsi_host_node)
+		goto error;
+
+	/*
+	 * Get the DSI host from the DSI host node. If we get an error
+	 * or the return is null assume we're not ready to probe just
+	 * yet. Release the DSI host node since we're done with it.
+	 */
+	*dsi_host = of_find_mipi_dsi_host_by_node(dsi_host_node);
+	of_node_put(dsi_host_node);
+	if (IS_ERR_OR_NULL(*dsi_host)) {
+		of_node_put(endpoint);
+		return -EPROBE_DEFER;
+	}
+
+	/*
+	 * Set the node of the mipi_dsi_device_info to the correct node
+	 * and then release the endpoint node since we're done with it.
+	 */
+	info->node = of_graph_get_remote_port(endpoint);
+	if (IS_ERR_OR_NULL(info->node))
+		goto error;
+
+	of_node_put(endpoint);
+	return 0;
+
+error:
+	of_node_put(endpoint);
+	return -ENODEV;
+}
+EXPORT_SYMBOL_GPL(drm_of_get_dsi_bus);
diff --git a/include/drm/drm_of.h b/include/drm/drm_of.h
index 10ab58c40746..a694ce71c3b2 100644
--- a/include/drm/drm_of.h
+++ b/include/drm/drm_of.h
@@ -15,6 +15,8 @@  struct drm_encoder;
 struct drm_panel;
 struct drm_bridge;
 struct device_node;
+struct mipi_dsi_device_info;
+struct mipi_dsi_host;
 
 /**
  * enum drm_lvds_dual_link_pixels - Pixel order of an LVDS dual-link connection
@@ -56,6 +58,9 @@  int drm_of_get_data_lanes_count_ep(const struct device_node *port,
 				   int port_reg, int reg,
 				   const unsigned int min,
 				   const unsigned int max);
+int drm_of_get_dsi_bus(struct device *dev,
+		       struct mipi_dsi_host **dsi_host,
+		       struct mipi_dsi_device_info *info);
 #else
 static inline uint32_t drm_of_crtc_port_mask(struct drm_device *dev,
 					  struct device_node *port)
@@ -127,6 +132,12 @@  drm_of_get_data_lanes_count_ep(const struct device_node *port,
 {
 	return -EINVAL;
 }
+static int drm_of_get_dsi_bus(struct device *dev,
+			      struct mipi_dsi_host **dsi_host,
+			      struct mipi_dsi_device_info *info);
+{
+	return -EINVAL;
+}
 #endif
 
 /*