[v5 0/5] drm: Support basic DPCD backlight in panel-simple and add a new panel ATNA33XC20
This series adds the support for the eDP panel that needs the backlight controlling over the DP AUX channel using DPCD registers of the panel as per the VESA's standard.
This series also adds support for the Samsung eDP AMOLED panel that needs DP AUX to control the backlight, and introduces new delays in the @panel_desc.delay to support this panel.
This patch series depends on the following two series: - Doug's series [1], exposed the DP AUX channel to the panel-simple. - Lyude's series [2], introduced new drm helper functions for DPCD backlight.
This series is the logical successor to the series [3].
Changes in v1: - Created dpcd backlight helper with very basic functionality, added backlight registration in the ti-sn65dsi86 bridge driver.
Changes in v2: - Created a new DisplayPort aux backlight driver and moved the code from drm_dp_aux_backlight.c (v1) to the new driver.
Changes in v3: - Fixed module compilation (kernel test bot).
Changes in v4: - Added basic DPCD backlight support in panel-simple. - Added support for a new Samsung panel ATNA33XC20 that needs DPCD backlight controlling and has a requirement of delays between enable GPIO and regulator.
Changes in v5: Addressed review suggestions from Douglas: - Created a new API drm_panel_dp_aux_backlight() in drm_panel.c - Moved DP AUX backlight functions from panel-simple.c to drm_panel.c - panel-simple probe() calls drm_panel_dp_aux_backlight() to create backlight when the backlight phandle is not specified in panel DT and DP AUX channel is present. - Added check for drm_edp_backlight_supported() before registering. - Removed the @uses_dpcd_backlight flag from panel_desc as this should be auto-detected. - Updated comments/descriptions.
[1] https://lore.kernel.org/dri-devel/20210525000159.3384921-1-dianders@chromium... [2] https://lore.kernel.org/dri-devel/20210514181504.565252-1-lyude@redhat.com/ [3] https://lore.kernel.org/dri-devel/1619416756-3533-1-git-send-email-rajeevny@...
Rajeev Nandan (5): drm/panel: add basic DP AUX backlight support drm/panel-simple: Support DP AUX backlight drm/panel-simple: Support for delays between GPIO & regulator dt-bindings: display: simple: Add Samsung ATNA33XC20 drm/panel-simple: Add Samsung ATNA33XC20
.../bindings/display/panel/panel-simple.yaml | 2 + drivers/gpu/drm/drm_panel.c | 108 +++++++++++++++++++++ drivers/gpu/drm/panel/panel-simple.c | 67 +++++++++++++ include/drm/drm_panel.h | 15 ++- 4 files changed, 188 insertions(+), 4 deletions(-)
Some panels support backlight control over DP AUX channel using VESA's standard backlight control interface. Using new DRM eDP backlight helpers, add support to create and register a backlight for those panels in drm_panel to simplify the panel drivers.
The panel driver with access to "struct drm_dp_aux" can create and register a backlight device using following code snippet in its probe() function:
err = drm_panel_dp_aux_backlight(panel, aux); if (err) return err;
Then drm_panel will handle backlight_(enable|disable) calls similar to the case when drm_panel_of_backlight() is used.
Currently, we are not supporting one feature where the source device can combine the backlight brightness levels set through DP AUX and the BL_PWM_DIM eDP connector pin. Since it's not required for the basic backlight controls, it can be added later.
Signed-off-by: Rajeev Nandan rajeevny@codeaurora.org ---
Changes in v5: - New (Douglas) [1]
[1] https://lore.kernel.org/dri-devel/CAD=FV=UuWuKibpT15McweuZ24qxsSAsSvJ3Q2MbZq...
drivers/gpu/drm/drm_panel.c | 108 ++++++++++++++++++++++++++++++++++++++++++++ include/drm/drm_panel.h | 15 ++++-- 2 files changed, 119 insertions(+), 4 deletions(-)
diff --git a/drivers/gpu/drm/drm_panel.c b/drivers/gpu/drm/drm_panel.c index f634371..f290315 100644 --- a/drivers/gpu/drm/drm_panel.c +++ b/drivers/gpu/drm/drm_panel.c @@ -26,12 +26,20 @@ #include <linux/module.h>
#include <drm/drm_crtc.h> +#include <drm/drm_dp_helper.h> #include <drm/drm_panel.h> #include <drm/drm_print.h>
static DEFINE_MUTEX(panel_lock); static LIST_HEAD(panel_list);
+struct dp_aux_backlight { + struct backlight_device *base; + struct drm_dp_aux *aux; + struct drm_edp_backlight_info info; + bool enabled; +}; + /** * DOC: drm panel * @@ -342,6 +350,106 @@ int drm_panel_of_backlight(struct drm_panel *panel) return 0; } EXPORT_SYMBOL(drm_panel_of_backlight); + +static int dp_aux_backlight_update_status(struct backlight_device *bd) +{ + struct dp_aux_backlight *bl = bl_get_data(bd); + u16 brightness = backlight_get_brightness(bd); + int ret = 0; + + if (brightness > 0) { + if (!bl->enabled) { + drm_edp_backlight_enable(bl->aux, &bl->info, brightness); + bl->enabled = true; + return 0; + } + ret = drm_edp_backlight_set_level(bl->aux, &bl->info, brightness); + } else { + if (bl->enabled) { + drm_edp_backlight_disable(bl->aux, &bl->info); + bl->enabled = false; + } + } + + return ret; +} + +static const struct backlight_ops dp_aux_bl_ops = { + .update_status = dp_aux_backlight_update_status, +}; + +/** + * drm_panel_dp_aux_backlight - create and use DP AUX backlight + * @panel: DRM panel + * @aux: The DP AUX channel to use + * + * Use this function to create and handle backlight if your panel + * supports backlight control over DP AUX channel using DPCD + * registers as per VESA's standard backlight control interface. + * + * When the panel is enabled backlight will be enabled after a + * successful call to &drm_panel_funcs.enable() + * + * When the panel is disabled backlight will be disabled before the + * call to &drm_panel_funcs.disable(). + * + * A typical implementation for a panel driver supporting backlight + * control over DP AUX will call this function at probe time. + * Backlight will then be handled transparently without requiring + * any intervention from the driver. + * + * drm_panel_dp_aux_backlight() must be called after the call to drm_panel_init(). + * + * Return: 0 on success or a negative error code on failure. + */ +int drm_panel_dp_aux_backlight(struct drm_panel *panel, struct drm_dp_aux *aux) +{ + struct dp_aux_backlight *bl; + struct backlight_properties props = { 0 }; + u16 current_level; + u8 current_mode; + u8 edp_dpcd[EDP_DISPLAY_CTL_CAP_SIZE]; + int ret; + + if (!panel || !panel->dev || !aux) + return -EINVAL; + + bl = devm_kzalloc(panel->dev, sizeof(*bl), GFP_KERNEL); + if (!bl) + return -ENOMEM; + + bl->aux = aux; + + ret = drm_dp_dpcd_read(aux, DP_EDP_DPCD_REV, edp_dpcd, + EDP_DISPLAY_CTL_CAP_SIZE); + if (ret < 0) + return ret; + + if (!drm_edp_backlight_supported(edp_dpcd)) { + DRM_DEV_INFO(panel->dev, "DP AUX backlight is not supported\n"); + return 0; + } + + ret = drm_edp_backlight_init(aux, &bl->info, 0, edp_dpcd, + ¤t_level, ¤t_mode); + if (ret < 0) + return ret; + + props.type = BACKLIGHT_RAW; + props.brightness = current_level; + props.max_brightness = bl->info.max; + + bl->base = devm_backlight_device_register(panel->dev, "dp_aux_backlight", + panel->dev, bl, + &dp_aux_bl_ops, &props); + if (IS_ERR(bl->base)) + return PTR_ERR(bl->base); + + panel->backlight = bl->base; + + return 0; +} +EXPORT_SYMBOL(drm_panel_dp_aux_backlight); #endif
MODULE_AUTHOR("Thierry Reding treding@nvidia.com"); diff --git a/include/drm/drm_panel.h b/include/drm/drm_panel.h index 33605c3..b1ba4de 100644 --- a/include/drm/drm_panel.h +++ b/include/drm/drm_panel.h @@ -32,6 +32,7 @@ struct backlight_device; struct device_node; struct drm_connector; struct drm_device; +struct drm_dp_aux; struct drm_panel; struct display_timing;
@@ -64,8 +65,8 @@ enum drm_panel_orientation; * the panel. This is the job of the .unprepare() function. * * Backlight can be handled automatically if configured using - * drm_panel_of_backlight(). Then the driver does not need to implement the - * functionality to enable/disable backlight. + * drm_panel_of_backlight() or drm_panel_dp_aux_backlight(). Then the driver + * does not need to implement the functionality to enable/disable backlight. */ struct drm_panel_funcs { /** @@ -144,8 +145,8 @@ struct drm_panel { * Backlight device, used to turn on backlight after the call * to enable(), and to turn off backlight before the call to * disable(). - * backlight is set by drm_panel_of_backlight() and drivers - * shall not assign it. + * backlight is set by drm_panel_of_backlight()/drm_panel_dp_aux_backlight() + * and drivers shall not assign it. */ struct backlight_device *backlight;
@@ -208,11 +209,17 @@ static inline int of_drm_get_panel_orientation(const struct device_node *np, #if IS_ENABLED(CONFIG_DRM_PANEL) && (IS_BUILTIN(CONFIG_BACKLIGHT_CLASS_DEVICE) || \ (IS_MODULE(CONFIG_DRM) && IS_MODULE(CONFIG_BACKLIGHT_CLASS_DEVICE))) int drm_panel_of_backlight(struct drm_panel *panel); +int drm_panel_dp_aux_backlight(struct drm_panel *panel, struct drm_dp_aux *aux); #else static inline int drm_panel_of_backlight(struct drm_panel *panel) { return 0; } +static inline int drm_panel_dp_aux_backlight(struct drm_panel *panel, + struct drm_dp_aux *aux) +{ + return 0; +} #endif
#endif
Hi Rajeev,
Thank you for the patch! Yet something to improve:
[auto build test ERROR on drm-intel/for-linux-next] [also build test ERROR on drm-tip/drm-tip drm-exynos/exynos-drm-next tegra-drm/drm/tegra/for-next linus/master v5.13-rc3 next-20210528] [cannot apply to drm/drm-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]
url: https://github.com/0day-ci/linux/commits/Rajeev-Nandan/drm-Support-basic-DPC... base: git://anongit.freedesktop.org/drm-intel for-linux-next config: openrisc-randconfig-r002-20210530 (attached as .config) compiler: or1k-linux-gcc (GCC) 9.3.0 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/0day-ci/linux/commit/1cf1b3f6b1f766d4e932422d1cdec19354ac... git remote add linux-review https://github.com/0day-ci/linux git fetch --no-tags linux-review Rajeev-Nandan/drm-Support-basic-DPCD-backlight-in-panel-simple-and-add-a-new-panel-ATNA33XC20/20210530-235810 git checkout 1cf1b3f6b1f766d4e932422d1cdec19354acdcc3 # save the attached .config to linux build tree COMPILER_INSTALL_PATH=$HOME/0day COMPILER=gcc-9.3.0 make.cross ARCH=openrisc
If you fix the issue, kindly add following tag as appropriate Reported-by: kernel test robot lkp@intel.com
All errors (new ones prefixed by >>):
drivers/gpu/drm/drm_panel.c:39:32: error: field 'info' has incomplete type
39 | struct drm_edp_backlight_info info; | ^~~~ drivers/gpu/drm/drm_panel.c: In function 'dp_aux_backlight_update_status':
drivers/gpu/drm/drm_panel.c:362:4: error: implicit declaration of function 'drm_edp_backlight_enable'; did you mean 'backlight_enable'? [-Werror=implicit-function-declaration]
362 | drm_edp_backlight_enable(bl->aux, &bl->info, brightness); | ^~~~~~~~~~~~~~~~~~~~~~~~ | backlight_enable
drivers/gpu/drm/drm_panel.c:366:9: error: implicit declaration of function 'drm_edp_backlight_set_level' [-Werror=implicit-function-declaration]
366 | ret = drm_edp_backlight_set_level(bl->aux, &bl->info, brightness); | ^~~~~~~~~~~~~~~~~~~~~~~~~~~
drivers/gpu/drm/drm_panel.c:369:4: error: implicit declaration of function 'drm_edp_backlight_disable'; did you mean 'backlight_disable'? [-Werror=implicit-function-declaration]
369 | drm_edp_backlight_disable(bl->aux, &bl->info); | ^~~~~~~~~~~~~~~~~~~~~~~~~ | backlight_disable drivers/gpu/drm/drm_panel.c: In function 'drm_panel_dp_aux_backlight':
drivers/gpu/drm/drm_panel.c:428:7: error: implicit declaration of function 'drm_edp_backlight_supported' [-Werror=implicit-function-declaration]
428 | if (!drm_edp_backlight_supported(edp_dpcd)) { | ^~~~~~~~~~~~~~~~~~~~~~~~~~~
drivers/gpu/drm/drm_panel.c:433:8: error: implicit declaration of function 'drm_edp_backlight_init' [-Werror=implicit-function-declaration]
433 | ret = drm_edp_backlight_init(aux, &bl->info, 0, edp_dpcd, | ^~~~~~~~~~~~~~~~~~~~~~ cc1: some warnings being treated as errors
Kconfig warnings: (for reference only) WARNING: unmet direct dependencies detected for LOCKDEP Depends on DEBUG_KERNEL && LOCK_DEBUGGING_SUPPORT && (FRAME_POINTER || MIPS || PPC || S390 || MICROBLAZE || ARM || ARC || X86) Selected by - PROVE_LOCKING && DEBUG_KERNEL && LOCK_DEBUGGING_SUPPORT - DEBUG_LOCK_ALLOC && DEBUG_KERNEL && LOCK_DEBUGGING_SUPPORT
vim +/info +39 drivers/gpu/drm/drm_panel.c
35 36 struct dp_aux_backlight { 37 struct backlight_device *base; 38 struct drm_dp_aux *aux;
39 struct drm_edp_backlight_info info;
40 bool enabled; 41 }; 42
--- 0-DAY CI Kernel Test Service, Intel Corporation https://lists.01.org/hyperkitty/list/kbuild-all@lists.01.org
Hi Rajeev,
Thank you for the patch! Yet something to improve:
[auto build test ERROR on drm-intel/for-linux-next] [also build test ERROR on drm-tip/drm-tip drm-exynos/exynos-drm-next tegra-drm/drm/tegra/for-next linus/master v5.13-rc3 next-20210528] [cannot apply to drm/drm-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]
url: https://github.com/0day-ci/linux/commits/Rajeev-Nandan/drm-Support-basic-DPC... base: git://anongit.freedesktop.org/drm-intel for-linux-next config: arm64-randconfig-r005-20210530 (attached as .config) compiler: clang version 13.0.0 (https://github.com/llvm/llvm-project bc6799f2f79f0ae87e9f1ebf9d25ba799fbd25a9) 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 # install arm64 cross compiling tool for clang build # apt-get install binutils-aarch64-linux-gnu # https://github.com/0day-ci/linux/commit/1cf1b3f6b1f766d4e932422d1cdec19354ac... git remote add linux-review https://github.com/0day-ci/linux git fetch --no-tags linux-review Rajeev-Nandan/drm-Support-basic-DPCD-backlight-in-panel-simple-and-add-a-new-panel-ATNA33XC20/20210530-235810 git checkout 1cf1b3f6b1f766d4e932422d1cdec19354acdcc3 # save the attached .config to linux build tree COMPILER_INSTALL_PATH=$HOME/0day COMPILER=clang make.cross ARCH=arm64
If you fix the issue, kindly add following tag as appropriate Reported-by: kernel test robot lkp@intel.com
All errors (new ones prefixed by >>):
drivers/gpu/drm/drm_panel.c:39:32: error: field has incomplete type 'struct drm_edp_backlight_info'
struct drm_edp_backlight_info info; ^ drivers/gpu/drm/drm_panel.c:39:9: note: forward declaration of 'struct drm_edp_backlight_info' struct drm_edp_backlight_info info; ^
drivers/gpu/drm/drm_panel.c:362:4: error: implicit declaration of function 'drm_edp_backlight_enable' [-Werror,-Wimplicit-function-declaration]
drm_edp_backlight_enable(bl->aux, &bl->info, brightness); ^ drivers/gpu/drm/drm_panel.c:362:4: note: did you mean 'backlight_enable'? include/linux/backlight.h:363:19: note: 'backlight_enable' declared here static inline int backlight_enable(struct backlight_device *bd) ^
drivers/gpu/drm/drm_panel.c:366:9: error: implicit declaration of function 'drm_edp_backlight_set_level' [-Werror,-Wimplicit-function-declaration]
ret = drm_edp_backlight_set_level(bl->aux, &bl->info, brightness); ^
drivers/gpu/drm/drm_panel.c:369:4: error: implicit declaration of function 'drm_edp_backlight_disable' [-Werror,-Wimplicit-function-declaration]
drm_edp_backlight_disable(bl->aux, &bl->info); ^ drivers/gpu/drm/drm_panel.c:369:4: note: did you mean 'backlight_disable'? include/linux/backlight.h:379:19: note: 'backlight_disable' declared here static inline int backlight_disable(struct backlight_device *bd) ^
drivers/gpu/drm/drm_panel.c:428:7: error: implicit declaration of function 'drm_edp_backlight_supported' [-Werror,-Wimplicit-function-declaration]
if (!drm_edp_backlight_supported(edp_dpcd)) { ^
drivers/gpu/drm/drm_panel.c:433:8: error: implicit declaration of function 'drm_edp_backlight_init' [-Werror,-Wimplicit-function-declaration]
ret = drm_edp_backlight_init(aux, &bl->info, 0, edp_dpcd, ^ 6 errors generated.
vim +39 drivers/gpu/drm/drm_panel.c
35 36 struct dp_aux_backlight { 37 struct backlight_device *base; 38 struct drm_dp_aux *aux;
39 struct drm_edp_backlight_info info;
40 bool enabled; 41 }; 42
--- 0-DAY CI Kernel Test Service, Intel Corporation https://lists.01.org/hyperkitty/list/kbuild-all@lists.01.org
Hi,
On Sun, May 30, 2021 at 8:57 AM Rajeev Nandan rajeevny@codeaurora.org wrote:
+static int dp_aux_backlight_update_status(struct backlight_device *bd) +{
struct dp_aux_backlight *bl = bl_get_data(bd);u16 brightness = backlight_get_brightness(bd);int ret = 0;if (brightness > 0) {if (!bl->enabled) {drm_edp_backlight_enable(bl->aux, &bl->info, brightness);bl->enabled = true;return 0;}ret = drm_edp_backlight_set_level(bl->aux, &bl->info, brightness);} else {if (bl->enabled) {drm_edp_backlight_disable(bl->aux, &bl->info);bl->enabled = false;}}
I was trying to figure out if there are any races / locking problems / problems trying to tweak the backlight when the panel is off. I don't _think_ there are. Specifically:
1. Before turning the panel off, drm_panel will call backlight_disable(). That will set BL_CORE_FBBLANK which is not set by any other calls. Then it will call your dp_aux_backlight_update_status().
2. Once BL_CORE_FBBLANK is set then backlight_get_brightness() will always return 0.
This means that a transition from 0 -> non-zero (and enable) will always only happen when the panel is on, which is good. It also means that we'll always transition to 0 (disable the backlight) when the panel turns off.
In terms of other races, it looks like the AUX transfer code handles grabbing a mutex around transfers so we should be safe there.
So I guess the above is just a long-winded way of saying that this looks right to me. :-)
BTW: we should probably make sure that the full set of people identified by `./scripts/get_maintainer.pl -f ./drivers/video/backlight` are CCed on your series. I see Daniel already and I've added the rest.
+/**
- drm_panel_dp_aux_backlight - create and use DP AUX backlight
- @panel: DRM panel
- @aux: The DP AUX channel to use
- Use this function to create and handle backlight if your panel
- supports backlight control over DP AUX channel using DPCD
- registers as per VESA's standard backlight control interface.
- When the panel is enabled backlight will be enabled after a
- successful call to &drm_panel_funcs.enable()
- When the panel is disabled backlight will be disabled before the
- call to &drm_panel_funcs.disable().
- A typical implementation for a panel driver supporting backlight
- control over DP AUX will call this function at probe time.
- Backlight will then be handled transparently without requiring
- any intervention from the driver.
- drm_panel_dp_aux_backlight() must be called after the call to drm_panel_init().
- Return: 0 on success or a negative error code on failure.
- */
+int drm_panel_dp_aux_backlight(struct drm_panel *panel, struct drm_dp_aux *aux) +{
struct dp_aux_backlight *bl;struct backlight_properties props = { 0 };u16 current_level;u8 current_mode;u8 edp_dpcd[EDP_DISPLAY_CTL_CAP_SIZE];int ret;if (!panel || !panel->dev || !aux)return -EINVAL;bl = devm_kzalloc(panel->dev, sizeof(*bl), GFP_KERNEL);if (!bl)return -ENOMEM;bl->aux = aux;ret = drm_dp_dpcd_read(aux, DP_EDP_DPCD_REV, edp_dpcd,EDP_DISPLAY_CTL_CAP_SIZE);if (ret < 0)return ret;if (!drm_edp_backlight_supported(edp_dpcd)) {DRM_DEV_INFO(panel->dev, "DP AUX backlight is not supported\n");return 0;}
nit: move this part up above the memory allocation. There's no reason to allocate memory for "bl" if the backlight isn't supported.
@@ -64,8 +65,8 @@ enum drm_panel_orientation;
- the panel. This is the job of the .unprepare() function.
- Backlight can be handled automatically if configured using
- drm_panel_of_backlight(). Then the driver does not need to implement the
- functionality to enable/disable backlight.
- drm_panel_of_backlight() or drm_panel_dp_aux_backlight(). Then the driver
*/
- does not need to implement the functionality to enable/disable backlight.
struct drm_panel_funcs { /** @@ -144,8 +145,8 @@ struct drm_panel { * Backlight device, used to turn on backlight after the call * to enable(), and to turn off backlight before the call to * disable().
* backlight is set by drm_panel_of_backlight() and drivers* shall not assign it.
* backlight is set by drm_panel_of_backlight()/drm_panel_dp_aux_backlight()* and drivers shall not assign it.
Slight nit that I would have wrapped the drm_panel_dp_aux_backlight() to the next line just to avoid one really long line followed by a short one.
Other than the two nits (ordering of memory allocation and word wrapping in a comment), this looks good to me. Feel free to add my Reviewed-by tag when you fix the nits.
NOTE: Even though I have commit access to drm-misc now, I wouldn't feel comfortable merging this to drm-misc myself without review feedback from someone more senior. Obviously we're still blocked on my and Lyude's series landing first, but even assuming those just land as-is we'll need some more adult supervision before this can land. ;-) That being said, I personally think this looks pretty nice now.
-Doug
*/ struct backlight_device *backlight;@@ -208,11 +209,17 @@ static inline int of_drm_get_panel_orientation(const struct device_node *np, #if IS_ENABLED(CONFIG_DRM_PANEL) && (IS_BUILTIN(CONFIG_BACKLIGHT_CLASS_DEVICE) || \ (IS_MODULE(CONFIG_DRM) && IS_MODULE(CONFIG_BACKLIGHT_CLASS_DEVICE))) int drm_panel_of_backlight(struct drm_panel *panel); +int drm_panel_dp_aux_backlight(struct drm_panel *panel, struct drm_dp_aux *aux); #else static inline int drm_panel_of_backlight(struct drm_panel *panel) { return 0; } +static inline int drm_panel_dp_aux_backlight(struct drm_panel *panel,
struct drm_dp_aux *aux)+{
return 0;+} #endif
#endif
2.7.4
On 03-06-2021 05:35, Doug Anderson wrote:
Hi,
On Sun, May 30, 2021 at 8:57 AM Rajeev Nandan rajeevny@codeaurora.org wrote:
Other than the two nits (ordering of memory allocation and word wrapping in a comment), this looks good to me. Feel free to add my Reviewed-by tag when you fix the nits.
NOTE: Even though I have commit access to drm-misc now, I wouldn't feel comfortable merging this to drm-misc myself without review feedback from someone more senior. Obviously we're still blocked on my and Lyude's series landing first, but even assuming those just land as-is we'll need some more adult supervision before this can land. ;-) That being said, I personally think this looks pretty nice now.
-Doug
Thank you, Doug.
I'll address the review comments of this patch and another patch (v5 3/5) in the next spin. I'll wait for Lyude to check this series, as she wanted to review it in a few days.
Thanks, Rajeev
If there is no backlight specified in the device tree and the panel has access to the DP AUX channel then create a DP AUX backlight if supported by the panel.
Signed-off-by: Rajeev Nandan rajeevny@codeaurora.org ---
This patch depends on [1] (drm/panel: panel-simple: Stash DP AUX bus; allow using it for DDC) and the previous patch (2/5) of this series.
Changes in v4: - New
Changes in v5: - Address review comments and move backlight functions to drm_panel.c (Douglas) - Create and register DP AUX backlight if there is no backlight specified in the device tree and panel has the DP AUX channel. (Douglas) - The new drm_panel_dp_aux_backlight() will do the drm_edp_backlight_supported() check.
[1] https://lore.kernel.org/dri-devel/20210524165920.v8.7.I18e60221f6d048d14d6c5...
drivers/gpu/drm/panel/panel-simple.c | 6 ++++++ 1 file changed, 6 insertions(+)
diff --git a/drivers/gpu/drm/panel/panel-simple.c b/drivers/gpu/drm/panel/panel-simple.c index b09be6e..047fad5 100644 --- a/drivers/gpu/drm/panel/panel-simple.c +++ b/drivers/gpu/drm/panel/panel-simple.c @@ -800,6 +800,12 @@ static int panel_simple_probe(struct device *dev, const struct panel_desc *desc, if (err) goto disable_pm_runtime;
+ if (!panel->base.backlight && panel->aux) { + err = drm_panel_dp_aux_backlight(&panel->base, panel->aux); + if (err) + goto disable_pm_runtime; + } + drm_panel_add(&panel->base);
return 0;
Hi Rajeev,
Thank you for the patch! Yet something to improve:
[auto build test ERROR on drm-intel/for-linux-next] [also build test ERROR on drm-tip/drm-tip drm-exynos/exynos-drm-next tegra-drm/drm/tegra/for-next linus/master v5.13-rc3 next-20210528] [cannot apply to drm/drm-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]
url: https://github.com/0day-ci/linux/commits/Rajeev-Nandan/drm-Support-basic-DPC... base: git://anongit.freedesktop.org/drm-intel for-linux-next config: x86_64-randconfig-a006-20210530 (attached as .config) compiler: clang version 13.0.0 (https://github.com/llvm/llvm-project bc6799f2f79f0ae87e9f1ebf9d25ba799fbd25a9) 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 # install x86_64 cross compiling tool for clang build # apt-get install binutils-x86-64-linux-gnu # https://github.com/0day-ci/linux/commit/fedf88beabe2c179d593bbb61ff5df62ac90... git remote add linux-review https://github.com/0day-ci/linux git fetch --no-tags linux-review Rajeev-Nandan/drm-Support-basic-DPCD-backlight-in-panel-simple-and-add-a-new-panel-ATNA33XC20/20210530-235810 git checkout fedf88beabe2c179d593bbb61ff5df62ac909fa1 # save the attached .config to linux build tree COMPILER_INSTALL_PATH=$HOME/0day COMPILER=clang make.cross ARCH=x86_64
If you fix the issue, kindly add following tag as appropriate Reported-by: kernel test robot lkp@intel.com
All errors (new ones prefixed by >>):
drivers/gpu/drm/panel/panel-simple.c:796:39: error: no member named 'aux' in 'struct panel_simple'
if (!panel->base.backlight && panel->aux) { ~~~~~ ^ include/linux/compiler.h:56:47: note: expanded from macro 'if' #define if(cond, ...) if ( __trace_if_var( !!(cond , ## __VA_ARGS__) ) ) ^~~~ include/linux/compiler.h:58:52: note: expanded from macro '__trace_if_var' #define __trace_if_var(cond) (__builtin_constant_p(cond) ? (cond) : __trace_if_value(cond)) ^~~~
drivers/gpu/drm/panel/panel-simple.c:796:39: error: no member named 'aux' in 'struct panel_simple'
if (!panel->base.backlight && panel->aux) { ~~~~~ ^ include/linux/compiler.h:56:47: note: expanded from macro 'if' #define if(cond, ...) if ( __trace_if_var( !!(cond , ## __VA_ARGS__) ) ) ^~~~ include/linux/compiler.h:58:61: note: expanded from macro '__trace_if_var' #define __trace_if_var(cond) (__builtin_constant_p(cond) ? (cond) : __trace_if_value(cond)) ^~~~
drivers/gpu/drm/panel/panel-simple.c:796:39: error: no member named 'aux' in 'struct panel_simple'
if (!panel->base.backlight && panel->aux) { ~~~~~ ^ include/linux/compiler.h:56:47: note: expanded from macro 'if' #define if(cond, ...) if ( __trace_if_var( !!(cond , ## __VA_ARGS__) ) ) ^~~~ include/linux/compiler.h:58:86: note: expanded from macro '__trace_if_var' #define __trace_if_var(cond) (__builtin_constant_p(cond) ? (cond) : __trace_if_value(cond)) ^~~~ include/linux/compiler.h:69:3: note: expanded from macro '__trace_if_value' (cond) ? \ ^~~~ drivers/gpu/drm/panel/panel-simple.c:797:57: error: no member named 'aux' in 'struct panel_simple' err = drm_panel_dp_aux_backlight(&panel->base, panel->aux); ~~~~~ ^ 4 errors generated.
vim +796 drivers/gpu/drm/panel/panel-simple.c
659 660 static int panel_simple_probe(struct device *dev, const struct panel_desc *desc) 661 { 662 struct panel_simple *panel; 663 struct display_timing dt; 664 struct device_node *ddc; 665 int connector_type; 666 u32 bus_flags; 667 int err; 668 669 panel = devm_kzalloc(dev, sizeof(*panel), GFP_KERNEL); 670 if (!panel) 671 return -ENOMEM; 672 673 panel->enabled = false; 674 panel->prepared_time = 0; 675 panel->desc = desc; 676 677 panel->no_hpd = of_property_read_bool(dev->of_node, "no-hpd"); 678 if (!panel->no_hpd) { 679 err = panel_simple_get_hpd_gpio(dev, panel); 680 if (err) 681 return err; 682 } 683 684 panel->supply = devm_regulator_get(dev, "power"); 685 if (IS_ERR(panel->supply)) 686 return PTR_ERR(panel->supply); 687 688 panel->enable_gpio = devm_gpiod_get_optional(dev, "enable", 689 GPIOD_OUT_LOW); 690 if (IS_ERR(panel->enable_gpio)) { 691 err = PTR_ERR(panel->enable_gpio); 692 if (err != -EPROBE_DEFER) 693 dev_err(dev, "failed to request GPIO: %d\n", err); 694 return err; 695 } 696 697 err = of_drm_get_panel_orientation(dev->of_node, &panel->orientation); 698 if (err) { 699 dev_err(dev, "%pOF: failed to get orientation %d\n", dev->of_node, err); 700 return err; 701 } 702 703 ddc = of_parse_phandle(dev->of_node, "ddc-i2c-bus", 0); 704 if (ddc) { 705 panel->ddc = of_find_i2c_adapter_by_node(ddc); 706 of_node_put(ddc); 707 708 if (!panel->ddc) 709 return -EPROBE_DEFER; 710 } 711 712 if (desc == &panel_dpi) { 713 /* Handle the generic panel-dpi binding */ 714 err = panel_dpi_probe(dev, panel); 715 if (err) 716 goto free_ddc; 717 } else { 718 if (!of_get_display_timing(dev->of_node, "panel-timing", &dt)) 719 panel_simple_parse_panel_timing_node(dev, panel, &dt); 720 } 721 722 connector_type = desc->connector_type; 723 /* Catch common mistakes for panels. */ 724 switch (connector_type) { 725 case 0: 726 dev_warn(dev, "Specify missing connector_type\n"); 727 connector_type = DRM_MODE_CONNECTOR_DPI; 728 break; 729 case DRM_MODE_CONNECTOR_LVDS: 730 WARN_ON(desc->bus_flags & 731 ~(DRM_BUS_FLAG_DE_LOW | 732 DRM_BUS_FLAG_DE_HIGH | 733 DRM_BUS_FLAG_DATA_MSB_TO_LSB | 734 DRM_BUS_FLAG_DATA_LSB_TO_MSB)); 735 WARN_ON(desc->bus_format != MEDIA_BUS_FMT_RGB666_1X7X3_SPWG && 736 desc->bus_format != MEDIA_BUS_FMT_RGB888_1X7X4_SPWG && 737 desc->bus_format != MEDIA_BUS_FMT_RGB888_1X7X4_JEIDA); 738 WARN_ON(desc->bus_format == MEDIA_BUS_FMT_RGB666_1X7X3_SPWG && 739 desc->bpc != 6); 740 WARN_ON((desc->bus_format == MEDIA_BUS_FMT_RGB888_1X7X4_SPWG || 741 desc->bus_format == MEDIA_BUS_FMT_RGB888_1X7X4_JEIDA) && 742 desc->bpc != 8); 743 break; 744 case DRM_MODE_CONNECTOR_eDP: 745 if (desc->bus_format == 0) 746 dev_warn(dev, "Specify missing bus_format\n"); 747 if (desc->bpc != 6 && desc->bpc != 8) 748 dev_warn(dev, "Expected bpc in {6,8} but got: %u\n", desc->bpc); 749 break; 750 case DRM_MODE_CONNECTOR_DSI: 751 if (desc->bpc != 6 && desc->bpc != 8) 752 dev_warn(dev, "Expected bpc in {6,8} but got: %u\n", desc->bpc); 753 break; 754 case DRM_MODE_CONNECTOR_DPI: 755 bus_flags = DRM_BUS_FLAG_DE_LOW | 756 DRM_BUS_FLAG_DE_HIGH | 757 DRM_BUS_FLAG_PIXDATA_SAMPLE_POSEDGE | 758 DRM_BUS_FLAG_PIXDATA_SAMPLE_NEGEDGE | 759 DRM_BUS_FLAG_DATA_MSB_TO_LSB | 760 DRM_BUS_FLAG_DATA_LSB_TO_MSB | 761 DRM_BUS_FLAG_SYNC_SAMPLE_POSEDGE | 762 DRM_BUS_FLAG_SYNC_SAMPLE_NEGEDGE; 763 if (desc->bus_flags & ~bus_flags) 764 dev_warn(dev, "Unexpected bus_flags(%d)\n", desc->bus_flags & ~bus_flags); 765 if (!(desc->bus_flags & bus_flags)) 766 dev_warn(dev, "Specify missing bus_flags\n"); 767 if (desc->bus_format == 0) 768 dev_warn(dev, "Specify missing bus_format\n"); 769 if (desc->bpc != 6 && desc->bpc != 8) 770 dev_warn(dev, "Expected bpc in {6,8} but got: %u\n", desc->bpc); 771 break; 772 default: 773 dev_warn(dev, "Specify a valid connector_type: %d\n", desc->connector_type); 774 connector_type = DRM_MODE_CONNECTOR_DPI; 775 break; 776 } 777 778 dev_set_drvdata(dev, panel); 779 780 /* 781 * We use runtime PM for prepare / unprepare since those power the panel 782 * on and off and those can be very slow operations. This is important 783 * to optimize powering the panel on briefly to read the EDID before 784 * fully enabling the panel. 785 */ 786 pm_runtime_enable(dev); 787 pm_runtime_set_autosuspend_delay(dev, 1000); 788 pm_runtime_use_autosuspend(dev); 789 790 drm_panel_init(&panel->base, dev, &panel_simple_funcs, connector_type); 791 792 err = drm_panel_of_backlight(&panel->base); 793 if (err) 794 goto disable_pm_runtime; 795
796 if (!panel->base.backlight && panel->aux) {
797 err = drm_panel_dp_aux_backlight(&panel->base, panel->aux); 798 if (err) 799 goto disable_pm_runtime; 800 } 801 802 drm_panel_add(&panel->base); 803 804 return 0; 805 806 disable_pm_runtime: 807 pm_runtime_disable(dev); 808 free_ddc: 809 if (panel->ddc) 810 put_device(&panel->ddc->dev); 811 812 return err; 813 } 814
--- 0-DAY CI Kernel Test Service, Intel Corporation https://lists.01.org/hyperkitty/list/kbuild-all@lists.01.org
Hi,
On Sun, May 30, 2021 at 8:57 AM Rajeev Nandan rajeevny@codeaurora.org wrote:
If there is no backlight specified in the device tree and the panel has access to the DP AUX channel then create a DP AUX backlight if supported by the panel.
Signed-off-by: Rajeev Nandan rajeevny@codeaurora.org
This patch depends on [1] (drm/panel: panel-simple: Stash DP AUX bus; allow using it for DDC) and the previous patch (2/5) of this series.
Changes in v4:
- New
Changes in v5:
- Address review comments and move backlight functions to drm_panel.c (Douglas)
- Create and register DP AUX backlight if there is no backlight specified in the device tree and panel has the DP AUX channel. (Douglas)
- The new drm_panel_dp_aux_backlight() will do the drm_edp_backlight_supported() check.
[1] https://lore.kernel.org/dri-devel/20210524165920.v8.7.I18e60221f6d048d14d6c5...
drivers/gpu/drm/panel/panel-simple.c | 6 ++++++ 1 file changed, 6 insertions(+)
diff --git a/drivers/gpu/drm/panel/panel-simple.c b/drivers/gpu/drm/panel/panel-simple.c index b09be6e..047fad5 100644 --- a/drivers/gpu/drm/panel/panel-simple.c +++ b/drivers/gpu/drm/panel/panel-simple.c @@ -800,6 +800,12 @@ static int panel_simple_probe(struct device *dev, const struct panel_desc *desc, if (err) goto disable_pm_runtime;
if (!panel->base.backlight && panel->aux) {err = drm_panel_dp_aux_backlight(&panel->base, panel->aux);if (err)goto disable_pm_runtime;}
It's so nice now!
Reviewed-by: Douglas Anderson dianders@chromium.org
Some panels datasheets may specify a delay between the enable GPIO and the regulator. Support this in panel-simple.
Signed-off-by: Rajeev Nandan rajeevny@codeaurora.org ---
Changes in v4: - New
Changes in v5: - Update description (Douglas) - Warn if "power_to_enable" or "disable_to_power_off" is non-zero and panel->enable_gpio is NULL (Douglas)
drivers/gpu/drm/panel/panel-simple.c | 28 ++++++++++++++++++++++++++++ 1 file changed, 28 insertions(+)
diff --git a/drivers/gpu/drm/panel/panel-simple.c b/drivers/gpu/drm/panel/panel-simple.c index 047fad5..e3f5b7e 100644 --- a/drivers/gpu/drm/panel/panel-simple.c +++ b/drivers/gpu/drm/panel/panel-simple.c @@ -133,6 +133,22 @@ struct panel_desc { unsigned int prepare_to_enable;
/** + * @delay.power_to_enable: Time for the power to enable the display on. + * + * The time (in milliseconds) to wait after powering up the display + * before asserting its enable pin. + */ + unsigned int power_to_enable; + + /** + * @delay.disable_to_power_off: Time for the disable to power the display off. + * + * The time (in milliseconds) to wait before powering off the display + * after deasserting its enable pin. + */ + unsigned int disable_to_power_off; + + /** * @delay.enable: Time for the panel to display a valid frame. * * The time (in milliseconds) that it takes for the panel to @@ -347,6 +363,10 @@ static int panel_simple_suspend(struct device *dev) struct panel_simple *p = dev_get_drvdata(dev);
gpiod_set_value_cansleep(p->enable_gpio, 0); + + if (p->desc->delay.disable_to_power_off) + msleep(p->desc->delay.disable_to_power_off); + regulator_disable(p->supply); p->unprepared_time = ktime_get();
@@ -407,6 +427,9 @@ static int panel_simple_prepare_once(struct panel_simple *p) return err; }
+ if (p->desc->delay.power_to_enable) + msleep(p->desc->delay.power_to_enable); + gpiod_set_value_cansleep(p->enable_gpio, 1);
delay = p->desc->delay.prepare; @@ -782,6 +805,11 @@ static int panel_simple_probe(struct device *dev, const struct panel_desc *desc, break; }
+ if (!panel->enable_gpio && desc->delay.disable_to_power_off) + dev_warn(dev, "Specify enable_gpio when using disable_to_power_off delay\n"); + if (!panel->enable_gpio && desc->delay.power_to_enable) + dev_warn(dev, "Specify enable_gpio when using power_to_enable delay\n"); + dev_set_drvdata(dev, panel);
/*
Hi,
On Sun, May 30, 2021 at 8:57 AM Rajeev Nandan rajeevny@codeaurora.org wrote:
Some panels datasheets may specify a delay between the enable GPIO and the regulator. Support this in panel-simple.
Signed-off-by: Rajeev Nandan rajeevny@codeaurora.org
Changes in v4:
- New
Changes in v5:
- Update description (Douglas)
- Warn if "power_to_enable" or "disable_to_power_off" is non-zero and panel->enable_gpio is NULL (Douglas)
drivers/gpu/drm/panel/panel-simple.c | 28 ++++++++++++++++++++++++++++ 1 file changed, 28 insertions(+)
diff --git a/drivers/gpu/drm/panel/panel-simple.c b/drivers/gpu/drm/panel/panel-simple.c index 047fad5..e3f5b7e 100644 --- a/drivers/gpu/drm/panel/panel-simple.c +++ b/drivers/gpu/drm/panel/panel-simple.c @@ -133,6 +133,22 @@ struct panel_desc { unsigned int prepare_to_enable;
/**
* @delay.power_to_enable: Time for the power to enable the display on.** The time (in milliseconds) to wait after powering up the display* before asserting its enable pin.*/unsigned int power_to_enable;/*** @delay.disable_to_power_off: Time for the disable to power the display off.** The time (in milliseconds) to wait before powering off the display* after deasserting its enable pin.*/unsigned int disable_to_power_off;/** * @delay.enable: Time for the panel to display a valid frame. * * The time (in milliseconds) that it takes for the panel to@@ -347,6 +363,10 @@ static int panel_simple_suspend(struct device *dev) struct panel_simple *p = dev_get_drvdata(dev);
gpiod_set_value_cansleep(p->enable_gpio, 0);
if (p->desc->delay.disable_to_power_off)msleep(p->desc->delay.disable_to_power_off);regulator_disable(p->supply); p->unprepared_time = ktime_get();@@ -407,6 +427,9 @@ static int panel_simple_prepare_once(struct panel_simple *p) return err; }
if (p->desc->delay.power_to_enable)msleep(p->desc->delay.power_to_enable);gpiod_set_value_cansleep(p->enable_gpio, 1); delay = p->desc->delay.prepare;@@ -782,6 +805,11 @@ static int panel_simple_probe(struct device *dev, const struct panel_desc *desc, break; }
if (!panel->enable_gpio && desc->delay.disable_to_power_off)dev_warn(dev, "Specify enable_gpio when using disable_to_power_off delay\n");if (!panel->enable_gpio && desc->delay.power_to_enable)dev_warn(dev, "Specify enable_gpio when using power_to_enable delay\n");
Last nit is that the warning messages could be a little confusing to someone reading the logs. I guess the target audience of the error message is probably someone doing bringup. That person specified a panel in their device tree and maybe isn't even aware that they're using "disable_to_power_off" or "power_to_enable". Maybe wording instead:
Need a delay after disabling panel GPIO, but a GPIO wasn't provided. Need a delay after enabling panel GPIO, but a GPIO wasn't provided.
That's definitely getting into nittiness, though and I wouldn't be upset if the patch landed with the existing messages. Thus, with or without the change to the error message:
Reviewed-by: Douglas Anderson dianders@chromium.org
Add Samsung 13.3" FHD eDP AMOLED panel.
Signed-off-by: Rajeev Nandan rajeevny@codeaurora.org Reviewed-by: Douglas Anderson dianders@chromium.org ---
(no changes since v4)
Changes in v4: - New
Documentation/devicetree/bindings/display/panel/panel-simple.yaml | 2 ++ 1 file changed, 2 insertions(+)
diff --git a/Documentation/devicetree/bindings/display/panel/panel-simple.yaml b/Documentation/devicetree/bindings/display/panel/panel-simple.yaml index 4a0a5e1..f5acfd6 100644 --- a/Documentation/devicetree/bindings/display/panel/panel-simple.yaml +++ b/Documentation/devicetree/bindings/display/panel/panel-simple.yaml @@ -242,6 +242,8 @@ properties: - rocktech,rk101ii01d-ct # Rocktech Display Ltd. RK070ER9427 800(RGB)x480 TFT LCD panel - rocktech,rk070er9427 + # Samsung 13.3" FHD (1920x1080 pixels) eDP AMOLED panel + - samsung,atna33xc20 # Samsung 12.2" (2560x1600 pixels) TFT LCD panel - samsung,lsn122dl01-c01 # Samsung Electronics 10.1" WSVGA TFT LCD panel
On Sun, 30 May 2021 21:26:11 +0530, Rajeev Nandan wrote:
Add Samsung 13.3" FHD eDP AMOLED panel.
Signed-off-by: Rajeev Nandan rajeevny@codeaurora.org Reviewed-by: Douglas Anderson dianders@chromium.org
(no changes since v4)
Changes in v4:
- New
Documentation/devicetree/bindings/display/panel/panel-simple.yaml | 2 ++ 1 file changed, 2 insertions(+)
Acked-by: Rob Herring robh@kernel.org
Add Samsung 13.3" FHD eDP AMOLED panel.
Signed-off-by: Rajeev Nandan rajeevny@codeaurora.org Reviewed-by: Douglas Anderson dianders@chromium.org ---
Changes in v4: - New
Changes in v5: - Remove "uses_dpcd_backlight" property, not required now. (Douglas)
drivers/gpu/drm/panel/panel-simple.c | 33 +++++++++++++++++++++++++++++++++ 1 file changed, 33 insertions(+)
diff --git a/drivers/gpu/drm/panel/panel-simple.c b/drivers/gpu/drm/panel/panel-simple.c index e3f5b7e..ce60517 100644 --- a/drivers/gpu/drm/panel/panel-simple.c +++ b/drivers/gpu/drm/panel/panel-simple.c @@ -3562,6 +3562,36 @@ static const struct panel_desc rocktech_rk101ii01d_ct = { .connector_type = DRM_MODE_CONNECTOR_LVDS, };
+static const struct drm_display_mode samsung_atna33xc20_mode = { + .clock = 138770, + .hdisplay = 1920, + .hsync_start = 1920 + 48, + .hsync_end = 1920 + 48 + 32, + .htotal = 1920 + 48 + 32 + 80, + .vdisplay = 1080, + .vsync_start = 1080 + 8, + .vsync_end = 1080 + 8 + 8, + .vtotal = 1080 + 8 + 8 + 16, + .flags = DRM_MODE_FLAG_PHSYNC | DRM_MODE_FLAG_NVSYNC, +}; + +static const struct panel_desc samsung_atna33xc20 = { + .modes = &samsung_atna33xc20_mode, + .num_modes = 1, + .bpc = 10, + .size = { + .width = 294, + .height = 165, + }, + .delay = { + .disable_to_power_off = 150, + .power_to_enable = 150, + .hpd_absent_delay = 200, + .unprepare = 500, + }, + .connector_type = DRM_MODE_CONNECTOR_eDP, +}; + static const struct drm_display_mode samsung_lsn122dl01_c01_mode = { .clock = 271560, .hdisplay = 2560, @@ -4563,6 +4593,9 @@ static const struct of_device_id platform_of_match[] = { .compatible = "rocktech,rk101ii01d-ct", .data = &rocktech_rk101ii01d_ct, }, { + .compatible = "samsung,atna33xc20", + .data = &samsung_atna33xc20, + }, { .compatible = "samsung,lsn122dl01-c01", .data = &samsung_lsn122dl01_c01, }, {
dri-devel@lists.freedesktop.org
-
Doug Anderson -
kernel test robot -
Rajeev Nandan -
rajeevny＠codeaurora.org
-
Rob Herring