[PATCH 0/9] drm: Add support for tiny LCD displays

[PATCH 0/9] drm: Add support for tiny LCD displays

[Noralf Trønnes]

This is an attempt at providing a DRM version of drivers/staging/fbtft.

The tinydrm library provides a very simplified view of DRM in particular
for tiny displays that has onboard video memory and is connected through
a slow bus like SPI/I2C.

Main changes since the RFCv2 in April last year:
- No tinydrm specific callbacks (dirtyfb+drm_panel_funcs), instead use
  drm_simple_display_pipe_funcs and drm_framebuffer_funcs directly in
  drivers and controller libraries.
- Drop lcdreg abstraction. MIPI DCS isn't really about registers, but
  rather commands with optional parameters. regmap is probably a good
  fit for the other more register oriented controllers.

I will cut back on some of the DRM_DEBUG*() usage when the api has settled.


Noralf.


Changes since RFC v2:
- Rebased on new core helpers
- Don't use drm_panel
- Flush when the framebuffer is changed on the plane
- Add devm_tinydrm_init()
- Fix PRIME support, set vaddr
- Use atomic helpers in suspend/resume
- Add a tinydrm_connector with one display mode
- Set mode_config.preferred_depth and use it for fbdev
- Subclass tinydrm_device in drivers instead of bloating the structure
- The PiTFT display uses a MI0283QT panel, write driver for that instead.
- Drop homegrown lcdreg module, it ended up as a collection of special
  cases.
- Add more documentation

Changes since RFC v1:
- Add fb_deferred_io support to drm_fb_helper and drm_fb_cma_helper,
  and use drm_fb_cma_helper instead.
- Move display pipeline code to drm_simple_kms_helper.
- Don't use (struct drm_driver *)->load().
- Make tinydrm more like a library, exporting the internals.
- Move the struct drm_driver definition from the tinydrm module to the
  driver using a helper macro: TINYDRM_DRM_DRIVER.
- Remove dirtyfb() async code.
- Added support for partial display updates.


Noralf Trønnes (9):
  drm/fb-cma-helper: Add drm_fbdev_cma_set_suspend_unlocked()
  drm: debugfs: Remove all files automatically on cleanup
  drm/simple-helpers: Add missing includes
  drm: Add DRM support for tiny LCD displays
  drm/tinydrm: Add helper functions
  drm/tinydrm: Add MIPI DBI support
  of: Add vendor prefix for Multi-Inno
  dt-bindings: Add Multi-Inno MI0283QT binding
  drm/tinydrm: Add support for Multi-Inno MI0283QT display

 .../bindings/display/multi-inno,mi0283qt.txt       |   27 +
 .../devicetree/bindings/vendor-prefixes.txt        |    1 +
 Documentation/gpu/drm-kms-helpers.rst              |   33 +
 MAINTAINERS                                        |   13 +
 drivers/gpu/drm/Kconfig                            |    2 +
 drivers/gpu/drm/Makefile                           |    1 +
 drivers/gpu/drm/drm_debugfs.c                      |   17 +-
 drivers/gpu/drm/drm_fb_cma_helper.c                |   18 +
 drivers/gpu/drm/tinydrm/Kconfig                    |   19 +
 drivers/gpu/drm/tinydrm/Makefile                   |    7 +
 drivers/gpu/drm/tinydrm/core/Makefile              |    3 +
 drivers/gpu/drm/tinydrm/core/tinydrm-core.c        |  374 ++++++++
 drivers/gpu/drm/tinydrm/core/tinydrm-helpers.c     |  490 ++++++++++
 drivers/gpu/drm/tinydrm/core/tinydrm-pipe.c        |  244 +++++
 drivers/gpu/drm/tinydrm/mi0283qt.c                 |  279 ++++++
 drivers/gpu/drm/tinydrm/mipi-dbi.c                 | 1005 ++++++++++++++++++++
 include/drm/drm_fb_cma_helper.h                    |    2 +
 include/drm/drm_simple_kms_helper.h                |    4 +
 include/drm/tinydrm/ili9341.h                      |   54 ++
 include/drm/tinydrm/mipi-dbi.h                     |  107 +++
 include/drm/tinydrm/tinydrm-helpers.h              |  100 ++
 include/drm/tinydrm/tinydrm.h                      |  115 +++
 22 files changed, 2913 insertions(+), 2 deletions(-)
 create mode 100644 Documentation/devicetree/bindings/display/multi-inno,mi0283qt.txt
 create mode 100644 drivers/gpu/drm/tinydrm/Kconfig
 create mode 100644 drivers/gpu/drm/tinydrm/Makefile
 create mode 100644 drivers/gpu/drm/tinydrm/core/Makefile
 create mode 100644 drivers/gpu/drm/tinydrm/core/tinydrm-core.c
 create mode 100644 drivers/gpu/drm/tinydrm/core/tinydrm-helpers.c
 create mode 100644 drivers/gpu/drm/tinydrm/core/tinydrm-pipe.c
 create mode 100644 drivers/gpu/drm/tinydrm/mi0283qt.c
 create mode 100644 drivers/gpu/drm/tinydrm/mipi-dbi.c
 create mode 100644 include/drm/tinydrm/ili9341.h
 create mode 100644 include/drm/tinydrm/mipi-dbi.h
 create mode 100644 include/drm/tinydrm/tinydrm-helpers.h
 create mode 100644 include/drm/tinydrm/tinydrm.h

--
2.10.2

--
To unsubscribe from this list: send the line "unsubscribe devicetree" in
the body of a message to majordomo-u79uwXL29TY76Z2rM5mHXA@public.gmane.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html

[PATCH 1/9] drm/fb-cma-helper: Add drm_fbdev_cma_set_suspend_unlocked()

[Noralf Trønnes]

Add a CMA version of drm_fb_helper_set_suspend_unlocked().

Cc: laurent.pinchart-ryLnwIuWjnjg/C1BVhZhaw@public.gmane.org
Signed-off-by: Noralf Trønnes <noralf-L59+Z2yzLopAfugRpC6u6w@public.gmane.org>
---
 drivers/gpu/drm/drm_fb_cma_helper.c | 18 ++++++++++++++++++
 include/drm/drm_fb_cma_helper.h     |  2 ++
 2 files changed, 20 insertions(+)

diff --git a/drivers/gpu/drm/drm_fb_cma_helper.c b/drivers/gpu/drm/drm_fb_cma_helper.c
index 4364abf..0ef8b28 100644
--- a/drivers/gpu/drm/drm_fb_cma_helper.c
+++ b/drivers/gpu/drm/drm_fb_cma_helper.c
@@ -622,3 +622,21 @@ void drm_fbdev_cma_set_suspend(struct drm_fbdev_cma *fbdev_cma, int state)
 		drm_fb_helper_set_suspend(&fbdev_cma->fb_helper, state);
 }
 EXPORT_SYMBOL(drm_fbdev_cma_set_suspend);
+
+/**
+ * drm_fbdev_cma_set_suspend_unlocked - wrapper around
+ *                                      drm_fb_helper_set_suspend_unlocked
+ * @fbdev_cma: The drm_fbdev_cma struct, may be NULL
+ * @state: desired state, zero to resume, non-zero to suspend
+ *
+ * Calls drm_fb_helper_set_suspend, which is a wrapper around
+ * fb_set_suspend implemented by fbdev core.
+ */
+void drm_fbdev_cma_set_suspend_unlocked(struct drm_fbdev_cma *fbdev_cma,
+					int state)
+{
+	if (fbdev_cma)
+		drm_fb_helper_set_suspend_unlocked(&fbdev_cma->fb_helper,
+						   state);
+}
+EXPORT_SYMBOL(drm_fbdev_cma_set_suspend_unlocked);
diff --git a/include/drm/drm_fb_cma_helper.h b/include/drm/drm_fb_cma_helper.h
index 9f4e34e..8dd6e55 100644
--- a/include/drm/drm_fb_cma_helper.h
+++ b/include/drm/drm_fb_cma_helper.h
@@ -26,6 +26,8 @@ void drm_fbdev_cma_fini(struct drm_fbdev_cma *fbdev_cma);
 void drm_fbdev_cma_restore_mode(struct drm_fbdev_cma *fbdev_cma);
 void drm_fbdev_cma_hotplug_event(struct drm_fbdev_cma *fbdev_cma);
 void drm_fbdev_cma_set_suspend(struct drm_fbdev_cma *fbdev_cma, int state);
+void drm_fbdev_cma_set_suspend_unlocked(struct drm_fbdev_cma *fbdev_cma,
+					int state);
 
 void drm_fb_cma_destroy(struct drm_framebuffer *fb);
 int drm_fb_cma_create_handle(struct drm_framebuffer *fb,
-- 
2.10.2

--
To unsubscribe from this list: send the line "unsubscribe devicetree" in
the body of a message to majordomo-u79uwXL29TY76Z2rM5mHXA@public.gmane.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html

Re: [PATCH 1/9] drm/fb-cma-helper: Add drm_fbdev_cma_set_suspend_unlocked()

[Daniel Vetter]

On Sun, Jan 22, 2017 at 07:11:09PM +0100, Noralf Trønnes wrote:
> Add a CMA version of drm_fb_helper_set_suspend_unlocked().
> 
> Cc: laurent.pinchart@ideasonboard.com
> Signed-off-by: Noralf Trønnes <noralf@tronnes.org>
> ---
>  drivers/gpu/drm/drm_fb_cma_helper.c | 18 ++++++++++++++++++
>  include/drm/drm_fb_cma_helper.h     |  2 ++
>  2 files changed, 20 insertions(+)
> 
> diff --git a/drivers/gpu/drm/drm_fb_cma_helper.c b/drivers/gpu/drm/drm_fb_cma_helper.c
> index 4364abf..0ef8b28 100644
> --- a/drivers/gpu/drm/drm_fb_cma_helper.c
> +++ b/drivers/gpu/drm/drm_fb_cma_helper.c
> @@ -622,3 +622,21 @@ void drm_fbdev_cma_set_suspend(struct drm_fbdev_cma *fbdev_cma, int state)
>  		drm_fb_helper_set_suspend(&fbdev_cma->fb_helper, state);
>  }
>  EXPORT_SYMBOL(drm_fbdev_cma_set_suspend);

Random idea for a cleanup series: Getting rid of
drm_fb_helper_set_suspend. I thinkf for almost all drivers we can use the
unlocked one, which has the upside that it doesn't stall the resume path
on the contended console_lock.

Anyway, applied this one here, thanks.
-Daniel

> +
> +/**
> + * drm_fbdev_cma_set_suspend_unlocked - wrapper around
> + *                                      drm_fb_helper_set_suspend_unlocked
> + * @fbdev_cma: The drm_fbdev_cma struct, may be NULL
> + * @state: desired state, zero to resume, non-zero to suspend
> + *
> + * Calls drm_fb_helper_set_suspend, which is a wrapper around
> + * fb_set_suspend implemented by fbdev core.
> + */
> +void drm_fbdev_cma_set_suspend_unlocked(struct drm_fbdev_cma *fbdev_cma,
> +					int state)
> +{
> +	if (fbdev_cma)
> +		drm_fb_helper_set_suspend_unlocked(&fbdev_cma->fb_helper,
> +						   state);
> +}
> +EXPORT_SYMBOL(drm_fbdev_cma_set_suspend_unlocked);
> diff --git a/include/drm/drm_fb_cma_helper.h b/include/drm/drm_fb_cma_helper.h
> index 9f4e34e..8dd6e55 100644
> --- a/include/drm/drm_fb_cma_helper.h
> +++ b/include/drm/drm_fb_cma_helper.h
> @@ -26,6 +26,8 @@ void drm_fbdev_cma_fini(struct drm_fbdev_cma *fbdev_cma);
>  void drm_fbdev_cma_restore_mode(struct drm_fbdev_cma *fbdev_cma);
>  void drm_fbdev_cma_hotplug_event(struct drm_fbdev_cma *fbdev_cma);
>  void drm_fbdev_cma_set_suspend(struct drm_fbdev_cma *fbdev_cma, int state);
> +void drm_fbdev_cma_set_suspend_unlocked(struct drm_fbdev_cma *fbdev_cma,
> +					int state);
>  
>  void drm_fb_cma_destroy(struct drm_framebuffer *fb);
>  int drm_fb_cma_create_handle(struct drm_framebuffer *fb,
> -- 
> 2.10.2
> 
> _______________________________________________
> dri-devel mailing list
> dri-devel@lists.freedesktop.org
> https://lists.freedesktop.org/mailman/listinfo/dri-devel

-- 
Daniel Vetter
Software Engineer, Intel Corporation
http://blog.ffwll.ch
_______________________________________________
dri-devel mailing list
dri-devel@lists.freedesktop.org
https://lists.freedesktop.org/mailman/listinfo/dri-devel

[PATCH 2/9] drm: debugfs: Remove all files automatically on cleanup

[Noralf Trønnes]

Instead of having the drivers call drm_debugfs_remove_files() in
their drm_driver->debugfs_cleanup hook, do it automatically by
traversing minor->debugfs_list.
Also use debugfs_remove_recursive() so drivers who add their own
debugfs files don't have to keep track of them for removal.

Signed-off-by: Noralf Trønnes <noralf-L59+Z2yzLopAfugRpC6u6w@public.gmane.org>
---
 drivers/gpu/drm/drm_debugfs.c | 17 +++++++++++++++--
 1 file changed, 15 insertions(+), 2 deletions(-)

diff --git a/drivers/gpu/drm/drm_debugfs.c b/drivers/gpu/drm/drm_debugfs.c
index 37fd612..0510ce2 100644
--- a/drivers/gpu/drm/drm_debugfs.c
+++ b/drivers/gpu/drm/drm_debugfs.c
@@ -218,6 +218,19 @@ int drm_debugfs_remove_files(const struct drm_info_list *files, int count,
 }
 EXPORT_SYMBOL(drm_debugfs_remove_files);
 
+static void drm_debugfs_remove_all_files(struct drm_minor *minor)
+{
+	struct drm_info_node *node, *tmp;
+
+	mutex_lock(&minor->debugfs_lock);
+	list_for_each_entry_safe(node, tmp, &minor->debugfs_list, list) {
+		debugfs_remove(node->dent);
+		list_del(&node->list);
+		kfree(node);
+	}
+	mutex_unlock(&minor->debugfs_lock);
+}
+
 /**
  * Cleanup the debugfs filesystem resources.
  *
@@ -245,9 +258,9 @@ int drm_debugfs_cleanup(struct drm_minor *minor)
 		}
 	}
 
-	drm_debugfs_remove_files(drm_debugfs_list, DRM_DEBUGFS_ENTRIES, minor);
+	drm_debugfs_remove_all_files(minor);
 
-	debugfs_remove(minor->debugfs_root);
+	debugfs_remove_recursive(minor->debugfs_root);
 	minor->debugfs_root = NULL;
 
 	return 0;
-- 
2.10.2

--
To unsubscribe from this list: send the line "unsubscribe devicetree" in
the body of a message to majordomo-u79uwXL29TY76Z2rM5mHXA@public.gmane.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html

Re: [PATCH 2/9] drm: debugfs: Remove all files automatically on cleanup

[Daniel Vetter]

On Sun, Jan 22, 2017 at 07:11:10PM +0100, Noralf Trønnes wrote:
> Instead of having the drivers call drm_debugfs_remove_files() in
> their drm_driver->debugfs_cleanup hook, do it automatically by
> traversing minor->debugfs_list.
> Also use debugfs_remove_recursive() so drivers who add their own
> debugfs files don't have to keep track of them for removal.
> 
> Signed-off-by: Noralf Trønnes <noralf@tronnes.org>

Makes sense, but that leaves us with a pile of dead code in drivers? Can
you pls go through them and remove this all (including the debugfs_cleanup
hook), and then removing the remaining (now dead) code in the core?

Thanks, Daniel
> ---
>  drivers/gpu/drm/drm_debugfs.c | 17 +++++++++++++++--
>  1 file changed, 15 insertions(+), 2 deletions(-)
> 
> diff --git a/drivers/gpu/drm/drm_debugfs.c b/drivers/gpu/drm/drm_debugfs.c
> index 37fd612..0510ce2 100644
> --- a/drivers/gpu/drm/drm_debugfs.c
> +++ b/drivers/gpu/drm/drm_debugfs.c
> @@ -218,6 +218,19 @@ int drm_debugfs_remove_files(const struct drm_info_list *files, int count,
>  }
>  EXPORT_SYMBOL(drm_debugfs_remove_files);
>  
> +static void drm_debugfs_remove_all_files(struct drm_minor *minor)
> +{
> +	struct drm_info_node *node, *tmp;
> +
> +	mutex_lock(&minor->debugfs_lock);
> +	list_for_each_entry_safe(node, tmp, &minor->debugfs_list, list) {
> +		debugfs_remove(node->dent);
> +		list_del(&node->list);
> +		kfree(node);
> +	}
> +	mutex_unlock(&minor->debugfs_lock);
> +}
> +
>  /**
>   * Cleanup the debugfs filesystem resources.
>   *
> @@ -245,9 +258,9 @@ int drm_debugfs_cleanup(struct drm_minor *minor)
>  		}
>  	}
>  
> -	drm_debugfs_remove_files(drm_debugfs_list, DRM_DEBUGFS_ENTRIES, minor);
> +	drm_debugfs_remove_all_files(minor);
>  
> -	debugfs_remove(minor->debugfs_root);
> +	debugfs_remove_recursive(minor->debugfs_root);
>  	minor->debugfs_root = NULL;
>  
>  	return 0;
> -- 
> 2.10.2
> 
> _______________________________________________
> dri-devel mailing list
> dri-devel@lists.freedesktop.org
> https://lists.freedesktop.org/mailman/listinfo/dri-devel

-- 
Daniel Vetter
Software Engineer, Intel Corporation
http://blog.ffwll.ch
_______________________________________________
dri-devel mailing list
dri-devel@lists.freedesktop.org
https://lists.freedesktop.org/mailman/listinfo/dri-devel

[PATCH 3/9] drm/simple-helpers: Add missing includes

[Noralf Trønnes]

Add missing includes to pull in definitions for drm_crtc,
drm_plane and drm_encoder.

Signed-off-by: Noralf Trønnes <noralf-L59+Z2yzLopAfugRpC6u6w@public.gmane.org>
---
 include/drm/drm_simple_kms_helper.h | 4 ++++
 1 file changed, 4 insertions(+)

diff --git a/include/drm/drm_simple_kms_helper.h b/include/drm/drm_simple_kms_helper.h
index fe8c4ba..d138d08 100644
--- a/include/drm/drm_simple_kms_helper.h
+++ b/include/drm/drm_simple_kms_helper.h
@@ -10,6 +10,10 @@
 #ifndef __LINUX_DRM_SIMPLE_KMS_HELPER_H
 #define __LINUX_DRM_SIMPLE_KMS_HELPER_H
 
+#include <drm/drm_crtc.h>
+#include <drm/drm_encoder.h>
+#include <drm/drm_plane.h>
+
 struct drm_simple_display_pipe;
 
 /**
-- 
2.10.2

--
To unsubscribe from this list: send the line "unsubscribe devicetree" in
the body of a message to majordomo-u79uwXL29TY76Z2rM5mHXA@public.gmane.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html

[PATCH 4/9] drm: Add DRM support for tiny LCD displays

[Noralf Trønnes]

tinydrm provides helpers for very simple displays that can use
CMA backed framebuffers and need flushing on changes.

Signed-off-by: Noralf Trønnes <noralf-L59+Z2yzLopAfugRpC6u6w@public.gmane.org>
---
 Documentation/gpu/drm-kms-helpers.rst       |  15 ++
 MAINTAINERS                                 |   7 +
 drivers/gpu/drm/Kconfig                     |   2 +
 drivers/gpu/drm/Makefile                    |   1 +
 drivers/gpu/drm/tinydrm/Kconfig             |   8 +
 drivers/gpu/drm/tinydrm/Makefile            |   1 +
 drivers/gpu/drm/tinydrm/core/Makefile       |   3 +
 drivers/gpu/drm/tinydrm/core/tinydrm-core.c | 374 ++++++++++++++++++++++++++++
 drivers/gpu/drm/tinydrm/core/tinydrm-pipe.c | 244 ++++++++++++++++++
 include/drm/tinydrm/tinydrm.h               | 115 +++++++++
 10 files changed, 770 insertions(+)
 create mode 100644 drivers/gpu/drm/tinydrm/Kconfig
 create mode 100644 drivers/gpu/drm/tinydrm/Makefile
 create mode 100644 drivers/gpu/drm/tinydrm/core/Makefile
 create mode 100644 drivers/gpu/drm/tinydrm/core/tinydrm-core.c
 create mode 100644 drivers/gpu/drm/tinydrm/core/tinydrm-pipe.c
 create mode 100644 include/drm/tinydrm/tinydrm.h

diff --git a/Documentation/gpu/drm-kms-helpers.rst b/Documentation/gpu/drm-kms-helpers.rst
index 03040aa..a86bd7f 100644
--- a/Documentation/gpu/drm-kms-helpers.rst
+++ b/Documentation/gpu/drm-kms-helpers.rst
@@ -272,3 +272,18 @@ Auxiliary Modeset Helpers
 
 .. kernel-doc:: drivers/gpu/drm/drm_modeset_helper.c
    :export:
+
+tinydrm Helper Reference
+========================
+
+.. kernel-doc:: drivers/gpu/drm/tinydrm/core/tinydrm-core.c
+   :doc: overview
+
+.. kernel-doc:: include/drm/tinydrm/tinydrm.h
+   :internal:
+
+.. kernel-doc:: drivers/gpu/drm/tinydrm/core/tinydrm-core.c
+   :export:
+
+.. kernel-doc:: drivers/gpu/drm/tinydrm/core/tinydrm-pipe.c
+   :export:
diff --git a/MAINTAINERS b/MAINTAINERS
index 741f35f..817e0fe 100644
--- a/MAINTAINERS
+++ b/MAINTAINERS
@@ -4365,6 +4365,13 @@ DRM DRIVER FOR TDFX VIDEO CARDS
 S:	Orphan / Obsolete
 F:	drivers/gpu/drm/tdfx/
 
+DRM DRIVERS FOR TINY DISPLAYS
+M:	Noralf Trønnes <noralf-L59+Z2yzLopAfugRpC6u6w@public.gmane.org>
+W:	https://github.com/notro/tinydrm/wiki
+S:	Maintained
+F:	drivers/gpu/drm/tinydrm/
+F:	include/drm/tinydrm/
+
 DRM DRIVER FOR USB DISPLAYLINK VIDEO ADAPTERS
 M:	Dave Airlie <airlied-H+wXaHxf7aLQT0dZR+AlfA@public.gmane.org>
 S:	Odd Fixes
diff --git a/drivers/gpu/drm/Kconfig b/drivers/gpu/drm/Kconfig
index 90bc65d..88e01e08e 100644
--- a/drivers/gpu/drm/Kconfig
+++ b/drivers/gpu/drm/Kconfig
@@ -263,6 +263,8 @@ source "drivers/gpu/drm/mxsfb/Kconfig"
 
 source "drivers/gpu/drm/meson/Kconfig"
 
+source "drivers/gpu/drm/tinydrm/Kconfig"
+
 # Keep legacy drivers last
 
 menuconfig DRM_LEGACY
diff --git a/drivers/gpu/drm/Makefile b/drivers/gpu/drm/Makefile
index 92de399..3ee9579 100644
--- a/drivers/gpu/drm/Makefile
+++ b/drivers/gpu/drm/Makefile
@@ -94,3 +94,4 @@ obj-$(CONFIG_DRM_ARCPGU)+= arc/
 obj-y			+= hisilicon/
 obj-$(CONFIG_DRM_ZTE)	+= zte/
 obj-$(CONFIG_DRM_MXSFB)	+= mxsfb/
+obj-$(CONFIG_DRM_TINYDRM) += tinydrm/
diff --git a/drivers/gpu/drm/tinydrm/Kconfig b/drivers/gpu/drm/tinydrm/Kconfig
new file mode 100644
index 0000000..ffb873f
--- /dev/null
+++ b/drivers/gpu/drm/tinydrm/Kconfig
@@ -0,0 +1,8 @@
+menuconfig DRM_TINYDRM
+	tristate "Support for simple displays"
+	depends on DRM
+	select DRM_KMS_HELPER
+	select DRM_KMS_CMA_HELPER
+	help
+	  Choose this option if you have a tinydrm supported display.
+	  If M is selected the module will be called tinydrm.
diff --git a/drivers/gpu/drm/tinydrm/Makefile b/drivers/gpu/drm/tinydrm/Makefile
new file mode 100644
index 0000000..7476ed1
--- /dev/null
+++ b/drivers/gpu/drm/tinydrm/Makefile
@@ -0,0 +1 @@
+obj-$(CONFIG_DRM_TINYDRM)		+= core/
diff --git a/drivers/gpu/drm/tinydrm/core/Makefile b/drivers/gpu/drm/tinydrm/core/Makefile
new file mode 100644
index 0000000..4f14a0f
--- /dev/null
+++ b/drivers/gpu/drm/tinydrm/core/Makefile
@@ -0,0 +1,3 @@
+tinydrm-y := tinydrm-core.o tinydrm-pipe.o
+
+obj-$(CONFIG_DRM_TINYDRM) += tinydrm.o
diff --git a/drivers/gpu/drm/tinydrm/core/tinydrm-core.c b/drivers/gpu/drm/tinydrm/core/tinydrm-core.c
new file mode 100644
index 0000000..492b478
--- /dev/null
+++ b/drivers/gpu/drm/tinydrm/core/tinydrm-core.c
@@ -0,0 +1,374 @@
+/*
+ * Copyright (C) 2016 Noralf Trønnes
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ */
+
+#include <drm/drm_atomic.h>
+#include <drm/drm_atomic_helper.h>
+#include <drm/drm_crtc_helper.h>
+#include <drm/tinydrm/tinydrm.h>
+#include <linux/device.h>
+#include <linux/dma-buf.h>
+
+/**
+ * DOC: overview
+ *
+ * This library provides driver helpers for very simple display hardware.
+ *
+ * It is based on &drm_simple_display_pipe coupled with a &drm_connector which
+ * has only one fixed &drm_display_mode. The framebuffers are backed by the
+ * cma helper and have support for framebuffer flushing (dirty).
+ * fbdev support is also included.
+ *
+ * The driver allocates &tinydrm_device, initializes it using
+ * devm_tinydrm_init(), sets up the pipeline using tinydrm_display_pipe_init()
+ * and registers the DRM device using devm_tinydrm_register().
+ */
+
+/**
+ * tinydrm_lastclose - DRM lastclose helper
+ * @drm: DRM device
+ *
+ * This function ensures that fbdev is restored when drm_lastclose() is called
+ * on the last drm_release(). Drivers can use this as their
+ * &drm_driver->lastclose callback.
+ */
+void tinydrm_lastclose(struct drm_device *drm)
+{
+	struct tinydrm_device *tdev = drm->dev_private;
+
+	DRM_DEBUG_KMS("\n");
+	drm_fbdev_cma_restore_mode(tdev->fbdev_cma);
+}
+EXPORT_SYMBOL(tinydrm_lastclose);
+
+/**
+ * tinydrm_gem_cma_prime_import_sg_table - Produce a CMA GEM object from
+ *     another driver's scatter/gather table of pinned pages
+ * @drm: DRM device to import into
+ * @attach: DMA-BUF attachment
+ * @sgt: Scatter/gather table of pinned pages
+ *
+ * This function imports a scatter/gather table exported via DMA-BUF by
+ * another driver using drm_gem_cma_prime_import_sg_table(). It sets the
+ * kernel virtual address on the CMA object. Drivers should use this as their
+ * &drm_driver->gem_prime_import_sg_table callback if they need the virtual
+ * address. tinydrm_gem_cma_free_object() should be used in combination with
+ * this function.
+ *
+ * Returns:
+ * A pointer to a newly created GEM object or an ERR_PTR-encoded negative
+ * error code on failure.
+ */
+struct drm_gem_object *
+tinydrm_gem_cma_prime_import_sg_table(struct drm_device *drm,
+				      struct dma_buf_attachment *attach,
+				      struct sg_table *sgt)
+{
+	struct drm_gem_cma_object *cma_obj;
+	struct drm_gem_object *obj;
+	void *vaddr;
+
+	vaddr = dma_buf_vmap(attach->dmabuf);
+	if (!vaddr) {
+		DRM_ERROR("Failed to vmap PRIME buffer\n");
+		return ERR_PTR(-ENOMEM);
+	}
+
+	obj = drm_gem_cma_prime_import_sg_table(drm, attach, sgt);
+	if (IS_ERR(obj)) {
+		dma_buf_vunmap(attach->dmabuf, vaddr);
+		return obj;
+	}
+
+	cma_obj = to_drm_gem_cma_obj(obj);
+	cma_obj->vaddr = vaddr;
+
+	return obj;
+}
+EXPORT_SYMBOL(tinydrm_gem_cma_prime_import_sg_table);
+
+/**
+ * tinydrm_gem_cma_free_object - Free resources associated with a CMA GEM
+ *                               object
+ * @gem_obj: GEM object to free
+ *
+ * This function frees the backing memory of the CMA GEM object, cleans up the
+ * GEM object state and frees the memory used to store the object itself using
+ * drm_gem_cma_free_object(). It also handles PRIME buffers which has the kernel
+ * virtual address set by tinydrm_gem_cma_prime_import_sg_table(). Drivers
+ * can use this as their &drm_driver->gem_free_object callback.
+ */
+void tinydrm_gem_cma_free_object(struct drm_gem_object *gem_obj)
+{
+	if (gem_obj->import_attach) {
+		struct drm_gem_cma_object *cma_obj;
+
+		cma_obj = to_drm_gem_cma_obj(gem_obj);
+		dma_buf_vunmap(gem_obj->import_attach->dmabuf, cma_obj->vaddr);
+		cma_obj->vaddr = NULL;
+	}
+
+	drm_gem_cma_free_object(gem_obj);
+}
+EXPORT_SYMBOL_GPL(tinydrm_gem_cma_free_object);
+
+const struct file_operations tinydrm_fops = {
+	.owner		= THIS_MODULE,
+	.open		= drm_open,
+	.release	= drm_release,
+	.unlocked_ioctl	= drm_ioctl,
+#ifdef CONFIG_COMPAT
+	.compat_ioctl	= drm_compat_ioctl,
+#endif
+	.poll		= drm_poll,
+	.read		= drm_read,
+	.llseek		= no_llseek,
+	.mmap		= drm_gem_cma_mmap,
+};
+EXPORT_SYMBOL(tinydrm_fops);
+
+static struct drm_framebuffer *
+tinydrm_fb_create(struct drm_device *drm, struct drm_file *file_priv,
+		  const struct drm_mode_fb_cmd2 *mode_cmd)
+{
+	struct tinydrm_device *tdev = drm->dev_private;
+
+	return drm_fb_cma_create_with_funcs(drm, file_priv, mode_cmd,
+					    tdev->fb_funcs);
+}
+
+static const struct drm_mode_config_funcs tinydrm_mode_config_funcs = {
+	.fb_create = tinydrm_fb_create,
+	.atomic_check = drm_atomic_helper_check,
+	.atomic_commit = drm_atomic_helper_commit,
+};
+
+static int tinydrm_init(struct device *parent, struct tinydrm_device *tdev,
+			const struct drm_framebuffer_funcs *fb_funcs,
+			struct drm_driver *driver)
+{
+	struct drm_device *drm;
+
+	mutex_init(&tdev->dirty_lock);
+	tdev->fb_funcs = fb_funcs;
+
+	/*
+	 * We don't embed drm_device, because that prevent us from using
+	 * devm_kzalloc() to allocate tinydrm_device in the driver since
+	 * drm_dev_unref() frees the structure. The devm_ functions provide
+	 * for easy error handling.
+	 */
+	drm = drm_dev_alloc(driver, parent);
+	if (IS_ERR(drm))
+		return PTR_ERR(drm);
+
+	tdev->drm = drm;
+	drm->dev_private = tdev;
+	drm_mode_config_init(drm);
+	drm->mode_config.funcs = &tinydrm_mode_config_funcs;
+
+	return 0;
+}
+
+static void tinydrm_fini(struct tinydrm_device *tdev)
+{
+	DRM_DEBUG_KMS("\n");
+
+	drm_mode_config_cleanup(tdev->drm);
+	mutex_destroy(&tdev->dirty_lock);
+	tdev->drm->dev_private = NULL;
+	drm_dev_unref(tdev->drm);
+}
+
+static void devm_tinydrm_release(void *data)
+{
+	tinydrm_fini(data);
+}
+
+/**
+ * devm_tinydrm_init - Initialize tinydrm device
+ * @parent: Parent device object
+ * @tdev: tinydrm device
+ * @fb_funcs: Framebuffer functions
+ * @driver: DRM driver
+ *
+ * This function initializes @tdev, the underlying DRM device and it's
+ * mode_config. Resources will be automatically freed on driver detach (devres)
+ * using drm_mode_config_cleanup() and drm_dev_unref().
+ *
+ * Returns:
+ * Zero on success, negative error code on failure.
+ */
+int devm_tinydrm_init(struct device *parent, struct tinydrm_device *tdev,
+		      const struct drm_framebuffer_funcs *fb_funcs,
+		      struct drm_driver *driver)
+{
+	int ret;
+
+	ret = tinydrm_init(parent, tdev, fb_funcs, driver);
+	if (ret)
+		return ret;
+
+	ret = devm_add_action(parent, devm_tinydrm_release, tdev);
+	if (ret)
+		tinydrm_fini(tdev);
+
+	return ret;
+}
+EXPORT_SYMBOL(devm_tinydrm_init);
+
+static int tinydrm_register(struct tinydrm_device *tdev)
+{
+	struct drm_device *drm = tdev->drm;
+	int bpp = drm->mode_config.preferred_depth;
+	struct drm_fbdev_cma *fbdev;
+	int ret;
+
+	ret = drm_dev_register(tdev->drm, 0);
+	if (ret)
+		return ret;
+
+	fbdev = drm_fbdev_cma_init_with_funcs(drm, bpp ? bpp : 32,
+					      drm->mode_config.num_crtc,
+					      drm->mode_config.num_connector,
+					      tdev->fb_funcs);
+	if (IS_ERR(fbdev))
+		DRM_ERROR("Failed to initialize fbdev: %ld\n", PTR_ERR(fbdev));
+	else
+		tdev->fbdev_cma = fbdev;
+
+	return 0;
+}
+
+static void tinydrm_unregister(struct tinydrm_device *tdev)
+{
+	DRM_DEBUG_KMS("\n");
+
+	drm_crtc_force_disable_all(tdev->drm);
+
+	if (tdev->fbdev_cma)
+		drm_fbdev_cma_fini(tdev->fbdev_cma);
+
+	drm_dev_unregister(tdev->drm);
+}
+
+static void devm_tinydrm_register_release(void *data)
+{
+	tinydrm_unregister(data);
+}
+
+/**
+ * devm_tinydrm_register - Register tinydrm device
+ * @tdev: tinydrm device
+ *
+ * This function registers the underlying DRM device and fbdev.
+ * These resources will be automatically unregistered on driver detach (devres)
+ * and the display pipeline will be disabled.
+ *
+ * Returns:
+ * Zero on success, negative error code on failure.
+ */
+int devm_tinydrm_register(struct tinydrm_device *tdev)
+{
+	struct device *dev = tdev->drm->dev;
+	int ret;
+
+	ret = tinydrm_register(tdev);
+	if (ret)
+		return ret;
+
+	ret = devm_add_action(dev, devm_tinydrm_register_release, tdev);
+	if (ret)
+		tinydrm_unregister(tdev);
+
+	return ret;
+}
+EXPORT_SYMBOL(devm_tinydrm_register);
+
+/**
+ * tinydrm_shutdown - Shutdown tinydrm
+ * @tdev: tinydrm device
+ *
+ * This function makes sure that the display pipeline is disabled.
+ * Used by drivers in their shutdown callback to turn off the display
+ * on machine shutdown and reboot.
+ */
+void tinydrm_shutdown(struct tinydrm_device *tdev)
+{
+	drm_crtc_force_disable_all(tdev->drm);
+}
+EXPORT_SYMBOL(tinydrm_shutdown);
+
+/**
+ * tinydrm_suspend - Suspend tinydrm
+ * @tdev: tinydrm device
+ *
+ * Used in driver PM operations to suspend tinydrm.
+ * Suspends fbdev and DRM.
+ * Resume with tinydrm_resume().
+ *
+ * Returns:
+ * Zero on success, negative error code on failure.
+ */
+int tinydrm_suspend(struct tinydrm_device *tdev)
+{
+	struct drm_atomic_state *state;
+
+	if (tdev->suspend_state) {
+		DRM_ERROR("Failed to suspend: state already set\n");
+		return -EINVAL;
+	}
+
+	drm_fbdev_cma_set_suspend_unlocked(tdev->fbdev_cma, 1);
+	state = drm_atomic_helper_suspend(tdev->drm);
+	if (IS_ERR(state)) {
+		drm_fbdev_cma_set_suspend_unlocked(tdev->fbdev_cma, 0);
+		return PTR_ERR(state);
+	}
+
+	tdev->suspend_state = state;
+
+	return 0;
+}
+EXPORT_SYMBOL(tinydrm_suspend);
+
+/**
+ * tinydrm_resume - Resume tinydrm
+ * @tdev: tinydrm device
+ *
+ * Used in driver PM operations to resume tinydrm.
+ * Suspend with tinydrm_suspend().
+ *
+ * Returns:
+ * Zero on success, negative error code on failure.
+ */
+int tinydrm_resume(struct tinydrm_device *tdev)
+{
+	struct drm_atomic_state *state = tdev->suspend_state;
+	int ret;
+
+	if (!state) {
+		DRM_ERROR("Failed to resume: state is not set\n");
+		return -EINVAL;
+	}
+
+	tdev->suspend_state = NULL;
+
+	ret = drm_atomic_helper_resume(tdev->drm, state);
+	if (ret) {
+		DRM_ERROR("Error resuming state: %d\n", ret);
+		return ret;
+	}
+
+	drm_fbdev_cma_set_suspend_unlocked(tdev->fbdev_cma, 0);
+
+	return 0;
+}
+EXPORT_SYMBOL(tinydrm_resume);
+
+MODULE_LICENSE("GPL");
diff --git a/drivers/gpu/drm/tinydrm/core/tinydrm-pipe.c b/drivers/gpu/drm/tinydrm/core/tinydrm-pipe.c
new file mode 100644
index 0000000..4327b04
--- /dev/null
+++ b/drivers/gpu/drm/tinydrm/core/tinydrm-pipe.c
@@ -0,0 +1,244 @@
+/*
+ * Copyright (C) 2016 Noralf Trønnes
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ */
+
+#include <drm/drm_atomic_helper.h>
+#include <drm/drm_crtc_helper.h>
+#include <drm/drm_modes.h>
+#include <drm/tinydrm/tinydrm.h>
+
+struct tinydrm_connector {
+	struct drm_connector base;
+	const struct drm_display_mode *mode;
+};
+
+static inline struct tinydrm_connector *
+to_tinydrm_connector(struct drm_connector *connector)
+{
+	return container_of(connector, struct tinydrm_connector, base);
+}
+
+static int tinydrm_connector_get_modes(struct drm_connector *connector)
+{
+	struct tinydrm_connector *tconn = to_tinydrm_connector(connector);
+	struct drm_display_mode *mode;
+
+	mode = drm_mode_duplicate(connector->dev, tconn->mode);
+	if (!mode) {
+		DRM_ERROR("Failed to duplicate mode\n");
+		return 0;
+	}
+
+	if (mode->name[0] == '\0')
+		drm_mode_set_name(mode);
+
+	mode->type |= DRM_MODE_TYPE_PREFERRED;
+	drm_mode_probed_add(connector, mode);
+
+	if (mode->width_mm) {
+		connector->display_info.width_mm = mode->width_mm;
+		connector->display_info.height_mm = mode->height_mm;
+	}
+
+	return 1;
+}
+
+static const struct drm_connector_helper_funcs tinydrm_connector_hfuncs = {
+	.get_modes = tinydrm_connector_get_modes,
+	.best_encoder = drm_atomic_helper_best_encoder,
+};
+
+static enum drm_connector_status
+tinydrm_connector_detect(struct drm_connector *connector, bool force)
+{
+	if (drm_device_is_unplugged(connector->dev))
+		return connector_status_disconnected;
+
+	return connector->status;
+}
+
+static void tinydrm_connector_destroy(struct drm_connector *connector)
+{
+	struct tinydrm_connector *tconn = to_tinydrm_connector(connector);
+
+	drm_connector_cleanup(connector);
+	kfree(tconn);
+}
+
+static const struct drm_connector_funcs tinydrm_connector_funcs = {
+	.dpms = drm_atomic_helper_connector_dpms,
+	.reset = drm_atomic_helper_connector_reset,
+	.detect = tinydrm_connector_detect,
+	.fill_modes = drm_helper_probe_single_connector_modes,
+	.destroy = tinydrm_connector_destroy,
+	.atomic_duplicate_state = drm_atomic_helper_connector_duplicate_state,
+	.atomic_destroy_state = drm_atomic_helper_connector_destroy_state,
+};
+
+struct drm_connector *
+tinydrm_connector_create(struct drm_device *drm,
+			 const struct drm_display_mode *mode,
+			 int connector_type)
+{
+	struct tinydrm_connector *tconn;
+	struct drm_connector *connector;
+	int ret;
+
+	tconn = kzalloc(sizeof(*tconn), GFP_KERNEL);
+	if (!tconn)
+		return ERR_PTR(-ENOMEM);
+
+	tconn->mode = mode;
+	connector = &tconn->base;
+
+	drm_connector_helper_add(connector, &tinydrm_connector_hfuncs);
+	ret = drm_connector_init(drm, connector, &tinydrm_connector_funcs,
+				 connector_type);
+	if (ret) {
+		kfree(tconn);
+		return ERR_PTR(ret);
+	}
+
+	connector->status = connector_status_connected;
+
+	return connector;
+}
+
+/**
+ * tinydrm_display_pipe_update - Display pipe update helper
+ * @pipe: Simple display pipe
+ * @old_state: Old plane state
+ *
+ * This function does a full framebuffer flush if the plane framebuffer
+ * has changed. It also handles vblank events. Drivers can use this as their
+ * &drm_simple_display_pipe_funcs->update callback.
+ */
+void tinydrm_display_pipe_update(struct drm_simple_display_pipe *pipe,
+				 struct drm_plane_state *old_state)
+{
+	struct tinydrm_device *tdev = pipe_to_tinydrm(pipe);
+	struct drm_framebuffer *fb = pipe->plane.state->fb;
+	struct drm_crtc *crtc = &tdev->pipe.crtc;
+
+	if (!fb)
+		DRM_DEBUG_KMS("fb unset\n");
+	else if (!old_state->fb)
+		DRM_DEBUG_KMS("fb set\n");
+	else if (fb != old_state->fb)
+		DRM_DEBUG_KMS("fb changed\n");
+	else
+		DRM_DEBUG_KMS("No fb change\n");
+
+	if (fb && (fb != old_state->fb)) {
+		pipe->plane.fb = fb;
+		if (fb->funcs->dirty)
+			fb->funcs->dirty(fb, NULL, 0, 0, NULL, 0);
+	}
+
+	if (crtc->state->event) {
+		DRM_DEBUG_KMS("crtc event\n");
+		spin_lock_irq(&crtc->dev->event_lock);
+		drm_crtc_send_vblank_event(crtc, crtc->state->event);
+		spin_unlock_irq(&crtc->dev->event_lock);
+		crtc->state->event = NULL;
+	}
+}
+EXPORT_SYMBOL(tinydrm_display_pipe_update);
+
+/**
+ * tinydrm_display_pipe_prepare_fb - Display pipe prepare_fb helper
+ * @pipe: Simple display pipe
+ * @plane_state: Plane state
+ *
+ * This function uses drm_fb_cma_prepare_fb() to check if the plane FB has an
+ * dma-buf attached, extracts the exclusive fence and attaches it to plane
+ * state for the atomic helper to wait on. Drivers can use this as their
+ * &drm_simple_display_pipe_funcs->prepare_fb callback.
+ */
+int tinydrm_display_pipe_prepare_fb(struct drm_simple_display_pipe *pipe,
+				    struct drm_plane_state *plane_state)
+{
+	return drm_fb_cma_prepare_fb(&pipe->plane, plane_state);
+}
+EXPORT_SYMBOL(tinydrm_display_pipe_prepare_fb);
+
+static int tinydrm_rotate_mode(struct drm_display_mode *mode,
+			       unsigned int rotation)
+{
+	if (rotation == 0 || rotation == 180) {
+		return 0;
+	} else if (rotation == 90 || rotation == 270) {
+		swap(mode->hdisplay, mode->vdisplay);
+		swap(mode->hsync_start, mode->vsync_start);
+		swap(mode->hsync_end, mode->vsync_end);
+		swap(mode->htotal, mode->vtotal);
+		swap(mode->width_mm, mode->height_mm);
+		return 0;
+	} else {
+		return -EINVAL;
+	}
+}
+
+/**
+ * tinydrm_display_pipe_init - Initialize display pipe
+ * @tdev: tinydrm device
+ * @funcs: Display pipe functions
+ * @connector_type: Connector type
+ * @formats: Array of supported formats (DRM_FORMAT\_\*)
+ * @format_count: Number of elements in @formats
+ * @mode: Supported mode
+ * @rotation: Initial @mode rotation in degrees Counter Clock Wise
+ *
+ * This function sets up a &drm_simple_display_pipe with a &drm_connector that
+ * has one fixed &drm_display_mode which is rotated according to @rotation.
+ *
+ * Returns:
+ * Zero on success, negative error code on failure.
+ */
+int
+tinydrm_display_pipe_init(struct tinydrm_device *tdev,
+			  const struct drm_simple_display_pipe_funcs *funcs,
+			  int connector_type,
+			  const uint32_t *formats,
+			  unsigned int format_count,
+			  const struct drm_display_mode *mode,
+			  unsigned int rotation)
+{
+	struct drm_device *drm = tdev->drm;
+	struct drm_display_mode *mode_copy;
+	struct drm_connector *connector;
+	int ret;
+
+	mode_copy = devm_kmalloc(drm->dev, sizeof(*mode_copy), GFP_KERNEL);
+	if (!mode_copy)
+		return -ENOMEM;
+
+	*mode_copy = *mode;
+	ret = tinydrm_rotate_mode(mode_copy, rotation);
+	if (ret) {
+		DRM_ERROR("Illegal rotation value %u\n", rotation);
+		return -EINVAL;
+	}
+
+	drm->mode_config.min_width = mode_copy->hdisplay;
+	drm->mode_config.max_width = mode_copy->hdisplay;
+	drm->mode_config.min_height = mode_copy->vdisplay;
+	drm->mode_config.max_height = mode_copy->vdisplay;
+
+	connector = tinydrm_connector_create(drm, mode_copy, connector_type);
+	if (IS_ERR(connector))
+		return PTR_ERR(connector);
+
+	ret = drm_simple_display_pipe_init(drm, &tdev->pipe, funcs, formats,
+					   format_count, connector);
+	if (ret)
+		return ret;
+
+	return 0;
+}
+EXPORT_SYMBOL(tinydrm_display_pipe_init);
diff --git a/include/drm/tinydrm/tinydrm.h b/include/drm/tinydrm/tinydrm.h
new file mode 100644
index 0000000..cf9ca20
--- /dev/null
+++ b/include/drm/tinydrm/tinydrm.h
@@ -0,0 +1,115 @@
+/*
+ * Copyright (C) 2016 Noralf Trønnes
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ */
+
+#ifndef __LINUX_TINYDRM_H
+#define __LINUX_TINYDRM_H
+
+#include <drm/drm_gem_cma_helper.h>
+#include <drm/drm_fb_cma_helper.h>
+#include <drm/drm_simple_kms_helper.h>
+
+/**
+ * struct tinydrm_device - tinydrm device
+ * @drm: DRM device
+ * @pipe: Display pipe structure
+ * @dirty_lock: Serializes framebuffer flushing
+ * @fbdev_cma: CMA fbdev structure
+ * @suspend_state: Atomic state when suspended
+ * @fb_funcs: Framebuffer functions used when creating framebuffers
+ */
+struct tinydrm_device {
+	struct drm_device *drm;
+	struct drm_simple_display_pipe pipe;
+	struct mutex dirty_lock;
+	struct drm_fbdev_cma *fbdev_cma;
+	struct drm_atomic_state *suspend_state;
+	const struct drm_framebuffer_funcs *fb_funcs;
+};
+
+static inline struct tinydrm_device *
+pipe_to_tinydrm(struct drm_simple_display_pipe *pipe)
+{
+	return container_of(pipe, struct tinydrm_device, pipe);
+}
+
+/**
+ * TINYDRM_GEM_DRIVER_OPS - default tinydrm gem operations
+ *
+ * This macro provides a shortcut for setting the tinydrm GEM operations in
+ * the &drm_driver structure.
+ */
+#define TINYDRM_GEM_DRIVER_OPS \
+	.gem_free_object	= tinydrm_gem_cma_free_object, \
+	.gem_vm_ops		= &drm_gem_cma_vm_ops, \
+	.prime_handle_to_fd	= drm_gem_prime_handle_to_fd, \
+	.prime_fd_to_handle	= drm_gem_prime_fd_to_handle, \
+	.gem_prime_import	= drm_gem_prime_import, \
+	.gem_prime_export	= drm_gem_prime_export, \
+	.gem_prime_get_sg_table	= drm_gem_cma_prime_get_sg_table, \
+	.gem_prime_import_sg_table = tinydrm_gem_cma_prime_import_sg_table, \
+	.gem_prime_vmap		= drm_gem_cma_prime_vmap, \
+	.gem_prime_vunmap	= drm_gem_cma_prime_vunmap, \
+	.gem_prime_mmap		= drm_gem_cma_prime_mmap, \
+	.dumb_create		= drm_gem_cma_dumb_create, \
+	.dumb_map_offset	= drm_gem_cma_dumb_map_offset, \
+	.dumb_destroy		= drm_gem_dumb_destroy, \
+	.fops			= &tinydrm_fops
+
+/**
+ * TINYDRM_MODE - tinydrm display mode
+ * @hd: Horizontal resolution, width
+ * @vd: Vertical resolution, height
+ * @hd_mm: Display width in millimeters
+ * @vd_mm: Display height in millimeters
+ *
+ * This macro creates a &drm_display_mode for use with tinydrm.
+ */
+#define TINYDRM_MODE(hd, vd, hd_mm, vd_mm) \
+	.hdisplay = (hd), \
+	.hsync_start = (hd), \
+	.hsync_end = (hd), \
+	.htotal = (hd), \
+	.vdisplay = (vd), \
+	.vsync_start = (vd), \
+	.vsync_end = (vd), \
+	.vtotal = (vd), \
+	.width_mm = (hd_mm), \
+	.height_mm = (vd_mm), \
+	.type = DRM_MODE_TYPE_DRIVER, \
+	.clock = 1 /* pass validation */
+
+extern const struct file_operations tinydrm_fops;
+void tinydrm_lastclose(struct drm_device *drm);
+void tinydrm_gem_cma_free_object(struct drm_gem_object *gem_obj);
+struct drm_gem_object *
+tinydrm_gem_cma_prime_import_sg_table(struct drm_device *drm,
+				      struct dma_buf_attachment *attach,
+				      struct sg_table *sgt);
+int devm_tinydrm_init(struct device *parent, struct tinydrm_device *tdev,
+		      const struct drm_framebuffer_funcs *fb_funcs,
+		      struct drm_driver *driver);
+int devm_tinydrm_register(struct tinydrm_device *tdev);
+void tinydrm_shutdown(struct tinydrm_device *tdev);
+int tinydrm_suspend(struct tinydrm_device *tdev);
+int tinydrm_resume(struct tinydrm_device *tdev);
+
+void tinydrm_display_pipe_update(struct drm_simple_display_pipe *pipe,
+				 struct drm_plane_state *old_state);
+int tinydrm_display_pipe_prepare_fb(struct drm_simple_display_pipe *pipe,
+				    struct drm_plane_state *plane_state);
+int
+tinydrm_display_pipe_init(struct tinydrm_device *tdev,
+			  const struct drm_simple_display_pipe_funcs *funcs,
+			  int connector_type,
+			  const uint32_t *formats,
+			  unsigned int format_count,
+			  const struct drm_display_mode *mode,
+			  unsigned int rotation);
+
+#endif /* __LINUX_TINYDRM_H */
-- 
2.10.2

--
To unsubscribe from this list: send the line "unsubscribe devicetree" in
the body of a message to majordomo-u79uwXL29TY76Z2rM5mHXA@public.gmane.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html

Re: [PATCH 4/9] drm: Add DRM support for tiny LCD displays

[Daniel Vetter]

On Sun, Jan 22, 2017 at 07:11:12PM +0100, Noralf Trønnes wrote:
> tinydrm provides helpers for very simple displays that can use
> CMA backed framebuffers and need flushing on changes.
> 
> Signed-off-by: Noralf Trønnes <noralf@tronnes.org>

Looks all pretty. A bunch of ideas below, but all optional. For merging I
think simplest to first get the core patches in through drm-misc, and then
you can submit a pull request to Dave for tinydrm+backends (just needs an
ack for the dt parts from dt maintainers), including MAINTAINERS entry.
Ack from my side.

Thanks, Daniel

> ---
>  Documentation/gpu/drm-kms-helpers.rst       |  15 ++
>  MAINTAINERS                                 |   7 +
>  drivers/gpu/drm/Kconfig                     |   2 +
>  drivers/gpu/drm/Makefile                    |   1 +
>  drivers/gpu/drm/tinydrm/Kconfig             |   8 +
>  drivers/gpu/drm/tinydrm/Makefile            |   1 +
>  drivers/gpu/drm/tinydrm/core/Makefile       |   3 +
>  drivers/gpu/drm/tinydrm/core/tinydrm-core.c | 374 ++++++++++++++++++++++++++++
>  drivers/gpu/drm/tinydrm/core/tinydrm-pipe.c | 244 ++++++++++++++++++
>  include/drm/tinydrm/tinydrm.h               | 115 +++++++++
>  10 files changed, 770 insertions(+)
>  create mode 100644 drivers/gpu/drm/tinydrm/Kconfig
>  create mode 100644 drivers/gpu/drm/tinydrm/Makefile
>  create mode 100644 drivers/gpu/drm/tinydrm/core/Makefile
>  create mode 100644 drivers/gpu/drm/tinydrm/core/tinydrm-core.c
>  create mode 100644 drivers/gpu/drm/tinydrm/core/tinydrm-pipe.c
>  create mode 100644 include/drm/tinydrm/tinydrm.h
> 
> diff --git a/Documentation/gpu/drm-kms-helpers.rst b/Documentation/gpu/drm-kms-helpers.rst
> index 03040aa..a86bd7f 100644
> --- a/Documentation/gpu/drm-kms-helpers.rst
> +++ b/Documentation/gpu/drm-kms-helpers.rst
> @@ -272,3 +272,18 @@ Auxiliary Modeset Helpers
>  
>  .. kernel-doc:: drivers/gpu/drm/drm_modeset_helper.c
>     :export:
> +
> +tinydrm Helper Reference
> +========================
> +
> +.. kernel-doc:: drivers/gpu/drm/tinydrm/core/tinydrm-core.c
> +   :doc: overview
> +
> +.. kernel-doc:: include/drm/tinydrm/tinydrm.h
> +   :internal:
> +
> +.. kernel-doc:: drivers/gpu/drm/tinydrm/core/tinydrm-core.c
> +   :export:
> +
> +.. kernel-doc:: drivers/gpu/drm/tinydrm/core/tinydrm-pipe.c
> +   :export:

Since tinydrm is more like a special driver than a helper I think it would
make sense to move the docs into the driver section, next to the include
for the i915 stuff. That means a new tinydrm.rst and including it in
gpu/index.rst.
> diff --git a/MAINTAINERS b/MAINTAINERS
> index 741f35f..817e0fe 100644
> --- a/MAINTAINERS
> +++ b/MAINTAINERS
> @@ -4365,6 +4365,13 @@ DRM DRIVER FOR TDFX VIDEO CARDS
>  S:	Orphan / Obsolete
>  F:	drivers/gpu/drm/tdfx/
>  
> +DRM DRIVERS FOR TINY DISPLAYS
> +M:	Noralf Trønnes <noralf@tronnes.org>
> +W:	https://github.com/notro/tinydrm/wiki
> +S:	Maintained
> +F:	drivers/gpu/drm/tinydrm/
> +F:	include/drm/tinydrm/
> +
>  DRM DRIVER FOR USB DISPLAYLINK VIDEO ADAPTERS
>  M:	Dave Airlie <airlied@redhat.com>
>  S:	Odd Fixes
> diff --git a/drivers/gpu/drm/Kconfig b/drivers/gpu/drm/Kconfig
> index 90bc65d..88e01e08e 100644
> --- a/drivers/gpu/drm/Kconfig
> +++ b/drivers/gpu/drm/Kconfig
> @@ -263,6 +263,8 @@ source "drivers/gpu/drm/mxsfb/Kconfig"
>  
>  source "drivers/gpu/drm/meson/Kconfig"
>  
> +source "drivers/gpu/drm/tinydrm/Kconfig"
> +
>  # Keep legacy drivers last
>  
>  menuconfig DRM_LEGACY
> diff --git a/drivers/gpu/drm/Makefile b/drivers/gpu/drm/Makefile
> index 92de399..3ee9579 100644
> --- a/drivers/gpu/drm/Makefile
> +++ b/drivers/gpu/drm/Makefile
> @@ -94,3 +94,4 @@ obj-$(CONFIG_DRM_ARCPGU)+= arc/
>  obj-y			+= hisilicon/
>  obj-$(CONFIG_DRM_ZTE)	+= zte/
>  obj-$(CONFIG_DRM_MXSFB)	+= mxsfb/
> +obj-$(CONFIG_DRM_TINYDRM) += tinydrm/
> diff --git a/drivers/gpu/drm/tinydrm/Kconfig b/drivers/gpu/drm/tinydrm/Kconfig
> new file mode 100644
> index 0000000..ffb873f
> --- /dev/null
> +++ b/drivers/gpu/drm/tinydrm/Kconfig
> @@ -0,0 +1,8 @@
> +menuconfig DRM_TINYDRM
> +	tristate "Support for simple displays"
> +	depends on DRM
> +	select DRM_KMS_HELPER
> +	select DRM_KMS_CMA_HELPER
> +	help
> +	  Choose this option if you have a tinydrm supported display.
> +	  If M is selected the module will be called tinydrm.
> diff --git a/drivers/gpu/drm/tinydrm/Makefile b/drivers/gpu/drm/tinydrm/Makefile
> new file mode 100644
> index 0000000..7476ed1
> --- /dev/null
> +++ b/drivers/gpu/drm/tinydrm/Makefile
> @@ -0,0 +1 @@
> +obj-$(CONFIG_DRM_TINYDRM)		+= core/
> diff --git a/drivers/gpu/drm/tinydrm/core/Makefile b/drivers/gpu/drm/tinydrm/core/Makefile
> new file mode 100644
> index 0000000..4f14a0f
> --- /dev/null
> +++ b/drivers/gpu/drm/tinydrm/core/Makefile
> @@ -0,0 +1,3 @@
> +tinydrm-y := tinydrm-core.o tinydrm-pipe.o
> +
> +obj-$(CONFIG_DRM_TINYDRM) += tinydrm.o
> diff --git a/drivers/gpu/drm/tinydrm/core/tinydrm-core.c b/drivers/gpu/drm/tinydrm/core/tinydrm-core.c
> new file mode 100644
> index 0000000..492b478
> --- /dev/null
> +++ b/drivers/gpu/drm/tinydrm/core/tinydrm-core.c
> @@ -0,0 +1,374 @@
> +/*
> + * Copyright (C) 2016 Noralf Trønnes
> + *
> + * This program is free software; you can redistribute it and/or modify
> + * it under the terms of the GNU General Public License as published by
> + * the Free Software Foundation; either version 2 of the License, or
> + * (at your option) any later version.
> + */
> +
> +#include <drm/drm_atomic.h>
> +#include <drm/drm_atomic_helper.h>
> +#include <drm/drm_crtc_helper.h>
> +#include <drm/tinydrm/tinydrm.h>
> +#include <linux/device.h>
> +#include <linux/dma-buf.h>
> +
> +/**
> + * DOC: overview
> + *
> + * This library provides driver helpers for very simple display hardware.
> + *
> + * It is based on &drm_simple_display_pipe coupled with a &drm_connector which
> + * has only one fixed &drm_display_mode. The framebuffers are backed by the
> + * cma helper and have support for framebuffer flushing (dirty).
> + * fbdev support is also included.
> + *
> + * The driver allocates &tinydrm_device, initializes it using
> + * devm_tinydrm_init(), sets up the pipeline using tinydrm_display_pipe_init()
> + * and registers the DRM device using devm_tinydrm_register().
> + */
> +
> +/**
> + * tinydrm_lastclose - DRM lastclose helper
> + * @drm: DRM device
> + *
> + * This function ensures that fbdev is restored when drm_lastclose() is called
> + * on the last drm_release(). Drivers can use this as their
> + * &drm_driver->lastclose callback.
> + */
> +void tinydrm_lastclose(struct drm_device *drm)
> +{
> +	struct tinydrm_device *tdev = drm->dev_private;
> +
> +	DRM_DEBUG_KMS("\n");
> +	drm_fbdev_cma_restore_mode(tdev->fbdev_cma);
> +}
> +EXPORT_SYMBOL(tinydrm_lastclose);

I wonder whether we should have a pointer in dev->mode_config for the
fbdev stuff, and then a helper for generic kms lastclose in the fbdev
helper (so that it's useable for both cma and non-cma drivers). We
copy-paste this one-liner wrapper sooooo many times.

Just an idea for a follow-up/separate series.

> +
> +/**
> + * tinydrm_gem_cma_prime_import_sg_table - Produce a CMA GEM object from
> + *     another driver's scatter/gather table of pinned pages
> + * @drm: DRM device to import into
> + * @attach: DMA-BUF attachment
> + * @sgt: Scatter/gather table of pinned pages
> + *
> + * This function imports a scatter/gather table exported via DMA-BUF by
> + * another driver using drm_gem_cma_prime_import_sg_table(). It sets the
> + * kernel virtual address on the CMA object. Drivers should use this as their
> + * &drm_driver->gem_prime_import_sg_table callback if they need the virtual
> + * address. tinydrm_gem_cma_free_object() should be used in combination with
> + * this function.
> + *
> + * Returns:
> + * A pointer to a newly created GEM object or an ERR_PTR-encoded negative
> + * error code on failure.
> + */
> +struct drm_gem_object *
> +tinydrm_gem_cma_prime_import_sg_table(struct drm_device *drm,
> +				      struct dma_buf_attachment *attach,
> +				      struct sg_table *sgt)
> +{
> +	struct drm_gem_cma_object *cma_obj;
> +	struct drm_gem_object *obj;
> +	void *vaddr;
> +
> +	vaddr = dma_buf_vmap(attach->dmabuf);
> +	if (!vaddr) {
> +		DRM_ERROR("Failed to vmap PRIME buffer\n");
> +		return ERR_PTR(-ENOMEM);
> +	}
> +
> +	obj = drm_gem_cma_prime_import_sg_table(drm, attach, sgt);
> +	if (IS_ERR(obj)) {
> +		dma_buf_vunmap(attach->dmabuf, vaddr);
> +		return obj;
> +	}
> +
> +	cma_obj = to_drm_gem_cma_obj(obj);
> +	cma_obj->vaddr = vaddr;
> +
> +	return obj;
> +}
> +EXPORT_SYMBOL(tinydrm_gem_cma_prime_import_sg_table);
> +
> +/**
> + * tinydrm_gem_cma_free_object - Free resources associated with a CMA GEM
> + *                               object
> + * @gem_obj: GEM object to free
> + *
> + * This function frees the backing memory of the CMA GEM object, cleans up the
> + * GEM object state and frees the memory used to store the object itself using
> + * drm_gem_cma_free_object(). It also handles PRIME buffers which has the kernel
> + * virtual address set by tinydrm_gem_cma_prime_import_sg_table(). Drivers
> + * can use this as their &drm_driver->gem_free_object callback.
> + */
> +void tinydrm_gem_cma_free_object(struct drm_gem_object *gem_obj)
> +{
> +	if (gem_obj->import_attach) {
> +		struct drm_gem_cma_object *cma_obj;
> +
> +		cma_obj = to_drm_gem_cma_obj(gem_obj);
> +		dma_buf_vunmap(gem_obj->import_attach->dmabuf, cma_obj->vaddr);
> +		cma_obj->vaddr = NULL;
> +	}
> +
> +	drm_gem_cma_free_object(gem_obj);
> +}
> +EXPORT_SYMBOL_GPL(tinydrm_gem_cma_free_object);
> +
> +const struct file_operations tinydrm_fops = {
> +	.owner		= THIS_MODULE,
> +	.open		= drm_open,
> +	.release	= drm_release,
> +	.unlocked_ioctl	= drm_ioctl,
> +#ifdef CONFIG_COMPAT
> +	.compat_ioctl	= drm_compat_ioctl,
> +#endif
> +	.poll		= drm_poll,
> +	.read		= drm_read,
> +	.llseek		= no_llseek,
> +	.mmap		= drm_gem_cma_mmap,
> +};
> +EXPORT_SYMBOL(tinydrm_fops);
> +
> +static struct drm_framebuffer *
> +tinydrm_fb_create(struct drm_device *drm, struct drm_file *file_priv,
> +		  const struct drm_mode_fb_cmd2 *mode_cmd)
> +{
> +	struct tinydrm_device *tdev = drm->dev_private;
> +
> +	return drm_fb_cma_create_with_funcs(drm, file_priv, mode_cmd,
> +					    tdev->fb_funcs);
> +}
> +
> +static const struct drm_mode_config_funcs tinydrm_mode_config_funcs = {
> +	.fb_create = tinydrm_fb_create,
> +	.atomic_check = drm_atomic_helper_check,
> +	.atomic_commit = drm_atomic_helper_commit,
> +};
> +
> +static int tinydrm_init(struct device *parent, struct tinydrm_device *tdev,
> +			const struct drm_framebuffer_funcs *fb_funcs,
> +			struct drm_driver *driver)
> +{
> +	struct drm_device *drm;
> +
> +	mutex_init(&tdev->dirty_lock);
> +	tdev->fb_funcs = fb_funcs;
> +
> +	/*
> +	 * We don't embed drm_device, because that prevent us from using
> +	 * devm_kzalloc() to allocate tinydrm_device in the driver since
> +	 * drm_dev_unref() frees the structure. The devm_ functions provide
> +	 * for easy error handling.
> +	 */
> +	drm = drm_dev_alloc(driver, parent);

There's a patch series from Chris Wilson to add a ->release callback and
properly fix this.

> +	if (IS_ERR(drm))
> +		return PTR_ERR(drm);
> +
> +	tdev->drm = drm;
> +	drm->dev_private = tdev;
> +	drm_mode_config_init(drm);
> +	drm->mode_config.funcs = &tinydrm_mode_config_funcs;
> +
> +	return 0;
> +}
> +
> +static void tinydrm_fini(struct tinydrm_device *tdev)
> +{
> +	DRM_DEBUG_KMS("\n");
> +
> +	drm_mode_config_cleanup(tdev->drm);
> +	mutex_destroy(&tdev->dirty_lock);
> +	tdev->drm->dev_private = NULL;
> +	drm_dev_unref(tdev->drm);
> +}
> +
> +static void devm_tinydrm_release(void *data)
> +{
> +	tinydrm_fini(data);
> +}
> +
> +/**
> + * devm_tinydrm_init - Initialize tinydrm device
> + * @parent: Parent device object
> + * @tdev: tinydrm device
> + * @fb_funcs: Framebuffer functions
> + * @driver: DRM driver
> + *
> + * This function initializes @tdev, the underlying DRM device and it's
> + * mode_config. Resources will be automatically freed on driver detach (devres)
> + * using drm_mode_config_cleanup() and drm_dev_unref().
> + *
> + * Returns:
> + * Zero on success, negative error code on failure.
> + */
> +int devm_tinydrm_init(struct device *parent, struct tinydrm_device *tdev,
> +		      const struct drm_framebuffer_funcs *fb_funcs,
> +		      struct drm_driver *driver)
> +{
> +	int ret;
> +
> +	ret = tinydrm_init(parent, tdev, fb_funcs, driver);
> +	if (ret)
> +		return ret;
> +
> +	ret = devm_add_action(parent, devm_tinydrm_release, tdev);
> +	if (ret)
> +		tinydrm_fini(tdev);
> +
> +	return ret;
> +}
> +EXPORT_SYMBOL(devm_tinydrm_init);
> +
> +static int tinydrm_register(struct tinydrm_device *tdev)
> +{
> +	struct drm_device *drm = tdev->drm;
> +	int bpp = drm->mode_config.preferred_depth;
> +	struct drm_fbdev_cma *fbdev;
> +	int ret;
> +
> +	ret = drm_dev_register(tdev->drm, 0);
> +	if (ret)
> +		return ret;
> +
> +	fbdev = drm_fbdev_cma_init_with_funcs(drm, bpp ? bpp : 32,
> +					      drm->mode_config.num_crtc,
> +					      drm->mode_config.num_connector,
> +					      tdev->fb_funcs);
> +	if (IS_ERR(fbdev))
> +		DRM_ERROR("Failed to initialize fbdev: %ld\n", PTR_ERR(fbdev));
> +	else
> +		tdev->fbdev_cma = fbdev;
> +
> +	return 0;
> +}
> +
> +static void tinydrm_unregister(struct tinydrm_device *tdev)
> +{
> +	DRM_DEBUG_KMS("\n");
> +
> +	drm_crtc_force_disable_all(tdev->drm);
> +
> +	if (tdev->fbdev_cma)
> +		drm_fbdev_cma_fini(tdev->fbdev_cma);
> +
> +	drm_dev_unregister(tdev->drm);
> +}
> +
> +static void devm_tinydrm_register_release(void *data)
> +{
> +	tinydrm_unregister(data);
> +}
> +
> +/**
> + * devm_tinydrm_register - Register tinydrm device
> + * @tdev: tinydrm device
> + *
> + * This function registers the underlying DRM device and fbdev.
> + * These resources will be automatically unregistered on driver detach (devres)
> + * and the display pipeline will be disabled.
> + *
> + * Returns:
> + * Zero on success, negative error code on failure.
> + */
> +int devm_tinydrm_register(struct tinydrm_device *tdev)
> +{
> +	struct device *dev = tdev->drm->dev;
> +	int ret;
> +
> +	ret = tinydrm_register(tdev);
> +	if (ret)
> +		return ret;
> +
> +	ret = devm_add_action(dev, devm_tinydrm_register_release, tdev);
> +	if (ret)
> +		tinydrm_unregister(tdev);
> +
> +	return ret;
> +}
> +EXPORT_SYMBOL(devm_tinydrm_register);
> +
> +/**
> + * tinydrm_shutdown - Shutdown tinydrm
> + * @tdev: tinydrm device
> + *
> + * This function makes sure that the display pipeline is disabled.
> + * Used by drivers in their shutdown callback to turn off the display
> + * on machine shutdown and reboot.
> + */
> +void tinydrm_shutdown(struct tinydrm_device *tdev)
> +{
> +	drm_crtc_force_disable_all(tdev->drm);
> +}
> +EXPORT_SYMBOL(tinydrm_shutdown);
> +
> +/**
> + * tinydrm_suspend - Suspend tinydrm
> + * @tdev: tinydrm device
> + *
> + * Used in driver PM operations to suspend tinydrm.
> + * Suspends fbdev and DRM.
> + * Resume with tinydrm_resume().
> + *
> + * Returns:
> + * Zero on success, negative error code on failure.
> + */
> +int tinydrm_suspend(struct tinydrm_device *tdev)
> +{
> +	struct drm_atomic_state *state;
> +
> +	if (tdev->suspend_state) {
> +		DRM_ERROR("Failed to suspend: state already set\n");
> +		return -EINVAL;
> +	}
> +
> +	drm_fbdev_cma_set_suspend_unlocked(tdev->fbdev_cma, 1);

Hm, random idea for faster suspend: On resume we can use the worker to
avoid stalling on console_lock. On suspedn we could use a
set_suspend_async/complete pair, which first launches the worker and later
on waits for it to complete. If we do this around the (usually rather
slow) call to drm_atomic_helper_suspend, then we could hide all that
latency.

> +	state = drm_atomic_helper_suspend(tdev->drm);
> +	if (IS_ERR(state)) {
> +		drm_fbdev_cma_set_suspend_unlocked(tdev->fbdev_cma, 0);
> +		return PTR_ERR(state);
> +	}
> +
> +	tdev->suspend_state = state;
> +
> +	return 0;
> +}
> +EXPORT_SYMBOL(tinydrm_suspend);
> +
> +/**
> + * tinydrm_resume - Resume tinydrm
> + * @tdev: tinydrm device
> + *
> + * Used in driver PM operations to resume tinydrm.
> + * Suspend with tinydrm_suspend().
> + *
> + * Returns:
> + * Zero on success, negative error code on failure.
> + */
> +int tinydrm_resume(struct tinydrm_device *tdev)
> +{
> +	struct drm_atomic_state *state = tdev->suspend_state;
> +	int ret;
> +
> +	if (!state) {
> +		DRM_ERROR("Failed to resume: state is not set\n");
> +		return -EINVAL;
> +	}
> +
> +	tdev->suspend_state = NULL;
> +
> +	ret = drm_atomic_helper_resume(tdev->drm, state);
> +	if (ret) {
> +		DRM_ERROR("Error resuming state: %d\n", ret);
> +		return ret;
> +	}
> +
> +	drm_fbdev_cma_set_suspend_unlocked(tdev->fbdev_cma, 0);
> +
> +	return 0;
> +}
> +EXPORT_SYMBOL(tinydrm_resume);
> +
> +MODULE_LICENSE("GPL");
> diff --git a/drivers/gpu/drm/tinydrm/core/tinydrm-pipe.c b/drivers/gpu/drm/tinydrm/core/tinydrm-pipe.c
> new file mode 100644
> index 0000000..4327b04
> --- /dev/null
> +++ b/drivers/gpu/drm/tinydrm/core/tinydrm-pipe.c
> @@ -0,0 +1,244 @@
> +/*
> + * Copyright (C) 2016 Noralf Trønnes
> + *
> + * This program is free software; you can redistribute it and/or modify
> + * it under the terms of the GNU General Public License as published by
> + * the Free Software Foundation; either version 2 of the License, or
> + * (at your option) any later version.
> + */
> +
> +#include <drm/drm_atomic_helper.h>
> +#include <drm/drm_crtc_helper.h>
> +#include <drm/drm_modes.h>
> +#include <drm/tinydrm/tinydrm.h>
> +
> +struct tinydrm_connector {
> +	struct drm_connector base;
> +	const struct drm_display_mode *mode;
> +};
> +
> +static inline struct tinydrm_connector *
> +to_tinydrm_connector(struct drm_connector *connector)
> +{
> +	return container_of(connector, struct tinydrm_connector, base);
> +}
> +
> +static int tinydrm_connector_get_modes(struct drm_connector *connector)
> +{
> +	struct tinydrm_connector *tconn = to_tinydrm_connector(connector);
> +	struct drm_display_mode *mode;
> +
> +	mode = drm_mode_duplicate(connector->dev, tconn->mode);
> +	if (!mode) {
> +		DRM_ERROR("Failed to duplicate mode\n");
> +		return 0;
> +	}
> +
> +	if (mode->name[0] == '\0')
> +		drm_mode_set_name(mode);
> +
> +	mode->type |= DRM_MODE_TYPE_PREFERRED;
> +	drm_mode_probed_add(connector, mode);
> +
> +	if (mode->width_mm) {
> +		connector->display_info.width_mm = mode->width_mm;
> +		connector->display_info.height_mm = mode->height_mm;
> +	}
> +
> +	return 1;
> +}
> +
> +static const struct drm_connector_helper_funcs tinydrm_connector_hfuncs = {
> +	.get_modes = tinydrm_connector_get_modes,
> +	.best_encoder = drm_atomic_helper_best_encoder,
> +};
> +
> +static enum drm_connector_status
> +tinydrm_connector_detect(struct drm_connector *connector, bool force)
> +{
> +	if (drm_device_is_unplugged(connector->dev))
> +		return connector_status_disconnected;
> +
> +	return connector->status;
> +}
> +
> +static void tinydrm_connector_destroy(struct drm_connector *connector)
> +{
> +	struct tinydrm_connector *tconn = to_tinydrm_connector(connector);
> +
> +	drm_connector_cleanup(connector);
> +	kfree(tconn);
> +}
> +
> +static const struct drm_connector_funcs tinydrm_connector_funcs = {
> +	.dpms = drm_atomic_helper_connector_dpms,
> +	.reset = drm_atomic_helper_connector_reset,
> +	.detect = tinydrm_connector_detect,
> +	.fill_modes = drm_helper_probe_single_connector_modes,
> +	.destroy = tinydrm_connector_destroy,
> +	.atomic_duplicate_state = drm_atomic_helper_connector_duplicate_state,
> +	.atomic_destroy_state = drm_atomic_helper_connector_destroy_state,
> +};
> +
> +struct drm_connector *
> +tinydrm_connector_create(struct drm_device *drm,
> +			 const struct drm_display_mode *mode,
> +			 int connector_type)
> +{
> +	struct tinydrm_connector *tconn;
> +	struct drm_connector *connector;
> +	int ret;
> +
> +	tconn = kzalloc(sizeof(*tconn), GFP_KERNEL);
> +	if (!tconn)
> +		return ERR_PTR(-ENOMEM);
> +
> +	tconn->mode = mode;
> +	connector = &tconn->base;
> +
> +	drm_connector_helper_add(connector, &tinydrm_connector_hfuncs);
> +	ret = drm_connector_init(drm, connector, &tinydrm_connector_funcs,
> +				 connector_type);
> +	if (ret) {
> +		kfree(tconn);
> +		return ERR_PTR(ret);
> +	}
> +
> +	connector->status = connector_status_connected;
> +
> +	return connector;
> +}
> +
> +/**
> + * tinydrm_display_pipe_update - Display pipe update helper
> + * @pipe: Simple display pipe
> + * @old_state: Old plane state
> + *
> + * This function does a full framebuffer flush if the plane framebuffer
> + * has changed. It also handles vblank events. Drivers can use this as their
> + * &drm_simple_display_pipe_funcs->update callback.
> + */
> +void tinydrm_display_pipe_update(struct drm_simple_display_pipe *pipe,
> +				 struct drm_plane_state *old_state)
> +{
> +	struct tinydrm_device *tdev = pipe_to_tinydrm(pipe);
> +	struct drm_framebuffer *fb = pipe->plane.state->fb;
> +	struct drm_crtc *crtc = &tdev->pipe.crtc;
> +
> +	if (!fb)
> +		DRM_DEBUG_KMS("fb unset\n");
> +	else if (!old_state->fb)
> +		DRM_DEBUG_KMS("fb set\n");
> +	else if (fb != old_state->fb)
> +		DRM_DEBUG_KMS("fb changed\n");
> +	else
> +		DRM_DEBUG_KMS("No fb change\n");
> +
> +	if (fb && (fb != old_state->fb)) {
> +		pipe->plane.fb = fb;
> +		if (fb->funcs->dirty)
> +			fb->funcs->dirty(fb, NULL, 0, 0, NULL, 0);

I like the idea, but my cunning long-term plan is that we'd extend the
atomic support to support a dirty rectangle. Together with the
non-blocking stuff we could then implement fb->funcs->dirty in terms of
atomic. But here you implement atomic in terms of ->dirty, and we'd end up
with a loop.

Personally I'd just drop this helper here and move this part into the
backend modules ...

> +	}
> +
> +	if (crtc->state->event) {
> +		DRM_DEBUG_KMS("crtc event\n");
> +		spin_lock_irq(&crtc->dev->event_lock);
> +		drm_crtc_send_vblank_event(crtc, crtc->state->event);
> +		spin_unlock_irq(&crtc->dev->event_lock);
> +		crtc->state->event = NULL;

... because this here is kinda a hack, since it's not synchronized with
the screen update. Otoh these tiny panels are kinda special.

> +	}
> +}
> +EXPORT_SYMBOL(tinydrm_display_pipe_update);
> +
> +/**
> + * tinydrm_display_pipe_prepare_fb - Display pipe prepare_fb helper
> + * @pipe: Simple display pipe
> + * @plane_state: Plane state
> + *
> + * This function uses drm_fb_cma_prepare_fb() to check if the plane FB has an
> + * dma-buf attached, extracts the exclusive fence and attaches it to plane
> + * state for the atomic helper to wait on. Drivers can use this as their
> + * &drm_simple_display_pipe_funcs->prepare_fb callback.
> + */
> +int tinydrm_display_pipe_prepare_fb(struct drm_simple_display_pipe *pipe,
> +				    struct drm_plane_state *plane_state)
> +{
> +	return drm_fb_cma_prepare_fb(&pipe->plane, plane_state);
> +}
> +EXPORT_SYMBOL(tinydrm_display_pipe_prepare_fb);
> +
> +static int tinydrm_rotate_mode(struct drm_display_mode *mode,
> +			       unsigned int rotation)
> +{
> +	if (rotation == 0 || rotation == 180) {
> +		return 0;
> +	} else if (rotation == 90 || rotation == 270) {
> +		swap(mode->hdisplay, mode->vdisplay);
> +		swap(mode->hsync_start, mode->vsync_start);
> +		swap(mode->hsync_end, mode->vsync_end);
> +		swap(mode->htotal, mode->vtotal);
> +		swap(mode->width_mm, mode->height_mm);
> +		return 0;
> +	} else {
> +		return -EINVAL;
> +	}
> +}
> +
> +/**
> + * tinydrm_display_pipe_init - Initialize display pipe
> + * @tdev: tinydrm device
> + * @funcs: Display pipe functions
> + * @connector_type: Connector type
> + * @formats: Array of supported formats (DRM_FORMAT\_\*)
> + * @format_count: Number of elements in @formats
> + * @mode: Supported mode
> + * @rotation: Initial @mode rotation in degrees Counter Clock Wise
> + *
> + * This function sets up a &drm_simple_display_pipe with a &drm_connector that
> + * has one fixed &drm_display_mode which is rotated according to @rotation.
> + *
> + * Returns:
> + * Zero on success, negative error code on failure.
> + */
> +int
> +tinydrm_display_pipe_init(struct tinydrm_device *tdev,
> +			  const struct drm_simple_display_pipe_funcs *funcs,
> +			  int connector_type,
> +			  const uint32_t *formats,
> +			  unsigned int format_count,
> +			  const struct drm_display_mode *mode,
> +			  unsigned int rotation)
> +{
> +	struct drm_device *drm = tdev->drm;
> +	struct drm_display_mode *mode_copy;
> +	struct drm_connector *connector;
> +	int ret;
> +
> +	mode_copy = devm_kmalloc(drm->dev, sizeof(*mode_copy), GFP_KERNEL);
> +	if (!mode_copy)
> +		return -ENOMEM;
> +
> +	*mode_copy = *mode;
> +	ret = tinydrm_rotate_mode(mode_copy, rotation);
> +	if (ret) {
> +		DRM_ERROR("Illegal rotation value %u\n", rotation);
> +		return -EINVAL;
> +	}
> +
> +	drm->mode_config.min_width = mode_copy->hdisplay;
> +	drm->mode_config.max_width = mode_copy->hdisplay;
> +	drm->mode_config.min_height = mode_copy->vdisplay;
> +	drm->mode_config.max_height = mode_copy->vdisplay;
> +
> +	connector = tinydrm_connector_create(drm, mode_copy, connector_type);
> +	if (IS_ERR(connector))
> +		return PTR_ERR(connector);
> +
> +	ret = drm_simple_display_pipe_init(drm, &tdev->pipe, funcs, formats,
> +					   format_count, connector);
> +	if (ret)
> +		return ret;
> +
> +	return 0;
> +}
> +EXPORT_SYMBOL(tinydrm_display_pipe_init);
> diff --git a/include/drm/tinydrm/tinydrm.h b/include/drm/tinydrm/tinydrm.h
> new file mode 100644
> index 0000000..cf9ca20
> --- /dev/null
> +++ b/include/drm/tinydrm/tinydrm.h
> @@ -0,0 +1,115 @@
> +/*
> + * Copyright (C) 2016 Noralf Trønnes
> + *
> + * This program is free software; you can redistribute it and/or modify
> + * it under the terms of the GNU General Public License as published by
> + * the Free Software Foundation; either version 2 of the License, or
> + * (at your option) any later version.
> + */
> +
> +#ifndef __LINUX_TINYDRM_H
> +#define __LINUX_TINYDRM_H
> +
> +#include <drm/drm_gem_cma_helper.h>
> +#include <drm/drm_fb_cma_helper.h>
> +#include <drm/drm_simple_kms_helper.h>
> +
> +/**
> + * struct tinydrm_device - tinydrm device
> + * @drm: DRM device
> + * @pipe: Display pipe structure
> + * @dirty_lock: Serializes framebuffer flushing
> + * @fbdev_cma: CMA fbdev structure
> + * @suspend_state: Atomic state when suspended
> + * @fb_funcs: Framebuffer functions used when creating framebuffers
> + */
> +struct tinydrm_device {
> +	struct drm_device *drm;
> +	struct drm_simple_display_pipe pipe;
> +	struct mutex dirty_lock;
> +	struct drm_fbdev_cma *fbdev_cma;
> +	struct drm_atomic_state *suspend_state;
> +	const struct drm_framebuffer_funcs *fb_funcs;
> +};
> +
> +static inline struct tinydrm_device *
> +pipe_to_tinydrm(struct drm_simple_display_pipe *pipe)
> +{
> +	return container_of(pipe, struct tinydrm_device, pipe);
> +}
> +
> +/**
> + * TINYDRM_GEM_DRIVER_OPS - default tinydrm gem operations
> + *
> + * This macro provides a shortcut for setting the tinydrm GEM operations in
> + * the &drm_driver structure.
> + */
> +#define TINYDRM_GEM_DRIVER_OPS \
> +	.gem_free_object	= tinydrm_gem_cma_free_object, \
> +	.gem_vm_ops		= &drm_gem_cma_vm_ops, \
> +	.prime_handle_to_fd	= drm_gem_prime_handle_to_fd, \
> +	.prime_fd_to_handle	= drm_gem_prime_fd_to_handle, \
> +	.gem_prime_import	= drm_gem_prime_import, \
> +	.gem_prime_export	= drm_gem_prime_export, \
> +	.gem_prime_get_sg_table	= drm_gem_cma_prime_get_sg_table, \
> +	.gem_prime_import_sg_table = tinydrm_gem_cma_prime_import_sg_table, \
> +	.gem_prime_vmap		= drm_gem_cma_prime_vmap, \
> +	.gem_prime_vunmap	= drm_gem_cma_prime_vunmap, \
> +	.gem_prime_mmap		= drm_gem_cma_prime_mmap, \
> +	.dumb_create		= drm_gem_cma_dumb_create, \
> +	.dumb_map_offset	= drm_gem_cma_dumb_map_offset, \
> +	.dumb_destroy		= drm_gem_dumb_destroy, \
> +	.fops			= &tinydrm_fops
> +
> +/**
> + * TINYDRM_MODE - tinydrm display mode
> + * @hd: Horizontal resolution, width
> + * @vd: Vertical resolution, height
> + * @hd_mm: Display width in millimeters
> + * @vd_mm: Display height in millimeters
> + *
> + * This macro creates a &drm_display_mode for use with tinydrm.
> + */
> +#define TINYDRM_MODE(hd, vd, hd_mm, vd_mm) \
> +	.hdisplay = (hd), \
> +	.hsync_start = (hd), \
> +	.hsync_end = (hd), \
> +	.htotal = (hd), \
> +	.vdisplay = (vd), \
> +	.vsync_start = (vd), \
> +	.vsync_end = (vd), \
> +	.vtotal = (vd), \
> +	.width_mm = (hd_mm), \
> +	.height_mm = (vd_mm), \
> +	.type = DRM_MODE_TYPE_DRIVER, \
> +	.clock = 1 /* pass validation */
> +
> +extern const struct file_operations tinydrm_fops;
> +void tinydrm_lastclose(struct drm_device *drm);
> +void tinydrm_gem_cma_free_object(struct drm_gem_object *gem_obj);
> +struct drm_gem_object *
> +tinydrm_gem_cma_prime_import_sg_table(struct drm_device *drm,
> +				      struct dma_buf_attachment *attach,
> +				      struct sg_table *sgt);
> +int devm_tinydrm_init(struct device *parent, struct tinydrm_device *tdev,
> +		      const struct drm_framebuffer_funcs *fb_funcs,
> +		      struct drm_driver *driver);
> +int devm_tinydrm_register(struct tinydrm_device *tdev);
> +void tinydrm_shutdown(struct tinydrm_device *tdev);
> +int tinydrm_suspend(struct tinydrm_device *tdev);
> +int tinydrm_resume(struct tinydrm_device *tdev);
> +
> +void tinydrm_display_pipe_update(struct drm_simple_display_pipe *pipe,
> +				 struct drm_plane_state *old_state);
> +int tinydrm_display_pipe_prepare_fb(struct drm_simple_display_pipe *pipe,
> +				    struct drm_plane_state *plane_state);
> +int
> +tinydrm_display_pipe_init(struct tinydrm_device *tdev,
> +			  const struct drm_simple_display_pipe_funcs *funcs,
> +			  int connector_type,
> +			  const uint32_t *formats,
> +			  unsigned int format_count,
> +			  const struct drm_display_mode *mode,
> +			  unsigned int rotation);
> +
> +#endif /* __LINUX_TINYDRM_H */
> -- 
> 2.10.2
> 
> _______________________________________________
> dri-devel mailing list
> dri-devel@lists.freedesktop.org
> https://lists.freedesktop.org/mailman/listinfo/dri-devel

-- 
Daniel Vetter
Software Engineer, Intel Corporation
http://blog.ffwll.ch

Re: [PATCH 4/9] drm: Add DRM support for tiny LCD displays

[Noralf Trønnes]

Den 23.01.2017 10.28, skrev Daniel Vetter:
> On Sun, Jan 22, 2017 at 07:11:12PM +0100, Noralf Trønnes wrote:
>> tinydrm provides helpers for very simple displays that can use
>> CMA backed framebuffers and need flushing on changes.
>>
>> Signed-off-by: Noralf Trønnes <noralf@tronnes.org>
> Looks all pretty. A bunch of ideas below, but all optional. For merging I
> think simplest to first get the core patches in through drm-misc, and then
> you can submit a pull request to Dave for tinydrm+backends (just needs an
> ack for the dt parts from dt maintainers), including MAINTAINERS entry.
> Ack from my side.

So when the tinydrm core patches are in:
- tinydrm patches are posted to dri-devel.
- DT patches need ack.
- If there's no comments or resolved, I send a pull request to Dave.

How often and when do I send pull requests?
(I have seen *-next, *-fixes, * for 4.xx)

Do drivers _always_ need a MAINTANERS entry, or is it preferred,
nice to have, not so important, ...


>> +/**
>> + * tinydrm_display_pipe_update - Display pipe update helper
>> + * @pipe: Simple display pipe
>> + * @old_state: Old plane state
>> + *
>> + * This function does a full framebuffer flush if the plane framebuffer
>> + * has changed. It also handles vblank events. Drivers can use this as their
>> + * &drm_simple_display_pipe_funcs->update callback.
>> + */
>> +void tinydrm_display_pipe_update(struct drm_simple_display_pipe *pipe,
>> +				 struct drm_plane_state *old_state)
>> +{
>> +	struct tinydrm_device *tdev = pipe_to_tinydrm(pipe);
>> +	struct drm_framebuffer *fb = pipe->plane.state->fb;
>> +	struct drm_crtc *crtc = &tdev->pipe.crtc;
>> +
>> +	if (!fb)
>> +		DRM_DEBUG_KMS("fb unset\n");
>> +	else if (!old_state->fb)
>> +		DRM_DEBUG_KMS("fb set\n");
>> +	else if (fb != old_state->fb)
>> +		DRM_DEBUG_KMS("fb changed\n");
>> +	else
>> +		DRM_DEBUG_KMS("No fb change\n");
>> +
>> +	if (fb && (fb != old_state->fb)) {
>> +		pipe->plane.fb = fb;
>> +		if (fb->funcs->dirty)
>> +			fb->funcs->dirty(fb, NULL, 0, 0, NULL, 0);
> I like the idea, but my cunning long-term plan is that we'd extend the
> atomic support to support a dirty rectangle. Together with the
> non-blocking stuff we could then implement fb->funcs->dirty in terms of
> atomic. But here you implement atomic in terms of ->dirty, and we'd end up
> with a loop.
>
> Personally I'd just drop this helper here and move this part into the
> backend modules ...
>
>> +	}
>> +
>> +	if (crtc->state->event) {
>> +		DRM_DEBUG_KMS("crtc event\n");
>> +		spin_lock_irq(&crtc->dev->event_lock);
>> +		drm_crtc_send_vblank_event(crtc, crtc->state->event);
>> +		spin_unlock_irq(&crtc->dev->event_lock);
>> +		crtc->state->event = NULL;
> ... because this here is kinda a hack, since it's not synchronized with
> the screen update. Otoh these tiny panels are kinda special.

Yeah, you're right it's only synchronized if the framebuffer changes.
So this won't catch events that's not page flip events.
afaict DRM_EVENT_VBLANK is the only other event. When is that used?

How about if I check for events as well so the fb is always flushed
if someone wants know?

void tinydrm_display_pipe_update(struct drm_simple_display_pipe *pipe,
                  struct drm_plane_state *old_state)
{
     struct tinydrm_device *tdev = pipe_to_tinydrm(pipe);
     struct drm_framebuffer *fb = pipe->plane.state->fb;
     struct drm_crtc *crtc = &tdev->pipe.crtc;

     if (fb && (fb != old_state->fb || crtc->state->event)) {
         pipe->plane.fb = fb;
         if (fb->funcs->dirty)
             fb->funcs->dirty(fb, NULL, 0, 0, NULL, 0);
     }

     if (crtc->state->event) {
         spin_lock_irq(&crtc->dev->event_lock);
         drm_crtc_send_vblank_event(crtc, crtc->state->event);
         spin_unlock_irq(&crtc->dev->event_lock);
         crtc->state->event = NULL;
     }
}


Or maybe I should send the event in the dirty() function instead?

void tinydrm_display_pipe_update(struct drm_simple_display_pipe *pipe,
                  struct drm_plane_state *old_state)
{
     struct tinydrm_device *tdev = pipe_to_tinydrm(pipe);
     struct drm_framebuffer *fb = pipe->plane.state->fb;
     struct drm_crtc *crtc = &tdev->pipe.crtc;

     if (fb && (fb != old_state->fb || crtc->state->event)) {
         pipe->plane.fb = fb;
         if (fb->funcs->dirty)
             fb->funcs->dirty(fb, NULL, 0, 0, NULL, 0);
     }
}

void tinydrm_send_pending_event(struct tinydrm_device *tdev)
{
     struct drm_crtc *crtc = &tdev->pipe.crtc;

     if (!crtc->state->event)
         return;

     spin_lock_irq(&crtc->dev->event_lock);
     drm_crtc_send_vblank_event(crtc, crtc->state->event);
     spin_unlock_irq(&crtc->dev->event_lock);
     crtc->state->event = NULL;
}

static int mipi_dbi_fb_dirty(struct drm_framebuffer *fb,
                  struct drm_file *file_priv,
                  unsigned int flags, unsigned int color,
                  struct drm_clip_rect *clips,
                  unsigned int num_clips)
{
     <snip>
     mutex_lock(&tdev->dirty_lock);

     <flush>

     tinydrm_send_pending_event(tdev);

     mutex_unlock(&tdev->dirty_lock);

     return ret;
}


Noralf.

Re: [PATCH 4/9] drm: Add DRM support for tiny LCD displays

[Jani Nikula]

On Tue, 24 Jan 2017, Noralf Trønnes <noralf@tronnes.org> wrote:
> Den 23.01.2017 10.28, skrev Daniel Vetter:
>> On Sun, Jan 22, 2017 at 07:11:12PM +0100, Noralf Trønnes wrote:
>>> tinydrm provides helpers for very simple displays that can use
>>> CMA backed framebuffers and need flushing on changes.
>>>
>>> Signed-off-by: Noralf Trønnes <noralf@tronnes.org>
>> Looks all pretty. A bunch of ideas below, but all optional. For merging I
>> think simplest to first get the core patches in through drm-misc, and then
>> you can submit a pull request to Dave for tinydrm+backends (just needs an
>> ack for the dt parts from dt maintainers), including MAINTAINERS entry.
>> Ack from my side.
>
> So when the tinydrm core patches are in:
> - tinydrm patches are posted to dri-devel.
> - DT patches need ack.
> - If there's no comments or resolved, I send a pull request to Dave.
>
> How often and when do I send pull requests?
> (I have seen *-next, *-fixes, * for 4.xx)

For DRM the cutoff for new features in the next merge window is around
-rc5 of the previous development kernels, i.e. the deadline for v4.11
merge window is around v4.10-rc5, pretty much now.

Pick up and send fixes pulls for current -rc kernels as needed. My flow
for i915 is to try to pick up stuff early in the week, let the stuff
simmer and go through our CI, and send the pull request to Dave by
Thursday.

> Do drivers _always_ need a MAINTANERS entry, or is it preferred,
> nice to have, not so important, ...

If you want the patches to flow through your tree, you need
it. Otherwise it'll fall under drm and drm-misc.


BR,
Jani.


>
>
>>> +/**
>>> + * tinydrm_display_pipe_update - Display pipe update helper
>>> + * @pipe: Simple display pipe
>>> + * @old_state: Old plane state
>>> + *
>>> + * This function does a full framebuffer flush if the plane framebuffer
>>> + * has changed. It also handles vblank events. Drivers can use this as their
>>> + * &drm_simple_display_pipe_funcs->update callback.
>>> + */
>>> +void tinydrm_display_pipe_update(struct drm_simple_display_pipe *pipe,
>>> +				 struct drm_plane_state *old_state)
>>> +{
>>> +	struct tinydrm_device *tdev = pipe_to_tinydrm(pipe);
>>> +	struct drm_framebuffer *fb = pipe->plane.state->fb;
>>> +	struct drm_crtc *crtc = &tdev->pipe.crtc;
>>> +
>>> +	if (!fb)
>>> +		DRM_DEBUG_KMS("fb unset\n");
>>> +	else if (!old_state->fb)
>>> +		DRM_DEBUG_KMS("fb set\n");
>>> +	else if (fb != old_state->fb)
>>> +		DRM_DEBUG_KMS("fb changed\n");
>>> +	else
>>> +		DRM_DEBUG_KMS("No fb change\n");
>>> +
>>> +	if (fb && (fb != old_state->fb)) {
>>> +		pipe->plane.fb = fb;
>>> +		if (fb->funcs->dirty)
>>> +			fb->funcs->dirty(fb, NULL, 0, 0, NULL, 0);
>> I like the idea, but my cunning long-term plan is that we'd extend the
>> atomic support to support a dirty rectangle. Together with the
>> non-blocking stuff we could then implement fb->funcs->dirty in terms of
>> atomic. But here you implement atomic in terms of ->dirty, and we'd end up
>> with a loop.
>>
>> Personally I'd just drop this helper here and move this part into the
>> backend modules ...
>>
>>> +	}
>>> +
>>> +	if (crtc->state->event) {
>>> +		DRM_DEBUG_KMS("crtc event\n");
>>> +		spin_lock_irq(&crtc->dev->event_lock);
>>> +		drm_crtc_send_vblank_event(crtc, crtc->state->event);
>>> +		spin_unlock_irq(&crtc->dev->event_lock);
>>> +		crtc->state->event = NULL;
>> ... because this here is kinda a hack, since it's not synchronized with
>> the screen update. Otoh these tiny panels are kinda special.
>
> Yeah, you're right it's only synchronized if the framebuffer changes.
> So this won't catch events that's not page flip events.
> afaict DRM_EVENT_VBLANK is the only other event. When is that used?
>
> How about if I check for events as well so the fb is always flushed
> if someone wants know?
>
> void tinydrm_display_pipe_update(struct drm_simple_display_pipe *pipe,
>                   struct drm_plane_state *old_state)
> {
>      struct tinydrm_device *tdev = pipe_to_tinydrm(pipe);
>      struct drm_framebuffer *fb = pipe->plane.state->fb;
>      struct drm_crtc *crtc = &tdev->pipe.crtc;
>
>      if (fb && (fb != old_state->fb || crtc->state->event)) {
>          pipe->plane.fb = fb;
>          if (fb->funcs->dirty)
>              fb->funcs->dirty(fb, NULL, 0, 0, NULL, 0);
>      }
>
>      if (crtc->state->event) {
>          spin_lock_irq(&crtc->dev->event_lock);
>          drm_crtc_send_vblank_event(crtc, crtc->state->event);
>          spin_unlock_irq(&crtc->dev->event_lock);
>          crtc->state->event = NULL;
>      }
> }
>
>
> Or maybe I should send the event in the dirty() function instead?
>
> void tinydrm_display_pipe_update(struct drm_simple_display_pipe *pipe,
>                   struct drm_plane_state *old_state)
> {
>      struct tinydrm_device *tdev = pipe_to_tinydrm(pipe);
>      struct drm_framebuffer *fb = pipe->plane.state->fb;
>      struct drm_crtc *crtc = &tdev->pipe.crtc;
>
>      if (fb && (fb != old_state->fb || crtc->state->event)) {
>          pipe->plane.fb = fb;
>          if (fb->funcs->dirty)
>              fb->funcs->dirty(fb, NULL, 0, 0, NULL, 0);
>      }
> }
>
> void tinydrm_send_pending_event(struct tinydrm_device *tdev)
> {
>      struct drm_crtc *crtc = &tdev->pipe.crtc;
>
>      if (!crtc->state->event)
>          return;
>
>      spin_lock_irq(&crtc->dev->event_lock);
>      drm_crtc_send_vblank_event(crtc, crtc->state->event);
>      spin_unlock_irq(&crtc->dev->event_lock);
>      crtc->state->event = NULL;
> }
>
> static int mipi_dbi_fb_dirty(struct drm_framebuffer *fb,
>                   struct drm_file *file_priv,
>                   unsigned int flags, unsigned int color,
>                   struct drm_clip_rect *clips,
>                   unsigned int num_clips)
> {
>      <snip>
>      mutex_lock(&tdev->dirty_lock);
>
>      <flush>
>
>      tinydrm_send_pending_event(tdev);
>
>      mutex_unlock(&tdev->dirty_lock);
>
>      return ret;
> }
>
>
> Noralf.
>
> _______________________________________________
> dri-devel mailing list
> dri-devel@lists.freedesktop.org
> https://lists.freedesktop.org/mailman/listinfo/dri-devel

-- 
Jani Nikula, Intel Open Source Technology Center

[PATCH 5/9] drm/tinydrm: Add helper functions

[Noralf Trønnes]

Add common functionality needed by many tinydrm drivers.

Signed-off-by: Noralf Trønnes <noralf@tronnes.org>
---
 Documentation/gpu/drm-kms-helpers.rst          |   6 +
 drivers/gpu/drm/tinydrm/core/Makefile          |   2 +-
 drivers/gpu/drm/tinydrm/core/tinydrm-helpers.c | 490 +++++++++++++++++++++++++
 include/drm/tinydrm/tinydrm-helpers.h          | 100 +++++
 4 files changed, 597 insertions(+), 1 deletion(-)
 create mode 100644 drivers/gpu/drm/tinydrm/core/tinydrm-helpers.c
 create mode 100644 include/drm/tinydrm/tinydrm-helpers.h

diff --git a/Documentation/gpu/drm-kms-helpers.rst b/Documentation/gpu/drm-kms-helpers.rst
index a86bd7f..be07e76 100644
--- a/Documentation/gpu/drm-kms-helpers.rst
+++ b/Documentation/gpu/drm-kms-helpers.rst
@@ -287,3 +287,9 @@ tinydrm Helper Reference
 
 .. kernel-doc:: drivers/gpu/drm/tinydrm/core/tinydrm-pipe.c
    :export:
+
+.. kernel-doc:: include/drm/tinydrm/tinydrm-helpers.h
+   :internal:
+
+.. kernel-doc:: drivers/gpu/drm/tinydrm/core/tinydrm-helpers.c
+   :export:
diff --git a/drivers/gpu/drm/tinydrm/core/Makefile b/drivers/gpu/drm/tinydrm/core/Makefile
index 4f14a0f..fb221e6 100644
--- a/drivers/gpu/drm/tinydrm/core/Makefile
+++ b/drivers/gpu/drm/tinydrm/core/Makefile
@@ -1,3 +1,3 @@
-tinydrm-y := tinydrm-core.o tinydrm-pipe.o
+tinydrm-y := tinydrm-core.o tinydrm-pipe.o tinydrm-helpers.o
 
 obj-$(CONFIG_DRM_TINYDRM) += tinydrm.o
diff --git a/drivers/gpu/drm/tinydrm/core/tinydrm-helpers.c b/drivers/gpu/drm/tinydrm/core/tinydrm-helpers.c
new file mode 100644
index 0000000..fc02e01
--- /dev/null
+++ b/drivers/gpu/drm/tinydrm/core/tinydrm-helpers.c
@@ -0,0 +1,490 @@
+/*
+ * Copyright (C) 2016 Noralf Trønnes
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ */
+
+#include <drm/tinydrm/tinydrm.h>
+#include <drm/tinydrm/tinydrm-helpers.h>
+#include <linux/backlight.h>
+#include <linux/pm.h>
+#include <linux/spi/spi.h>
+#include <linux/swab.h>
+
+static unsigned int spi_max;
+module_param(spi_max, uint, 0400);
+MODULE_PARM_DESC(spi_max, "Set a lower SPI max transfer size");
+
+/**
+ * tinydrm_merge_clips - Merge clip rectangles
+ * @dst: Destination clip rectangle
+ * @src: Source clip rectangle(s)
+ * @num_clips: Number of @src clip rectangles
+ * @flags: Dirty fb ioctl flags
+ * @max_width: Maximum width of @dst
+ * @max_height: Maximum height of @dst
+ *
+ * This function merges @src clip rectangle(s) into @dst. If @src is NULL,
+ * @max_width and @min_width is used to set a full @dst clip rectangle.
+ *
+ * Returns:
+ * true if it's a full clip, false otherwise
+ */
+bool tinydrm_merge_clips(struct drm_clip_rect *dst,
+			 struct drm_clip_rect *src, unsigned int num_clips,
+			 unsigned int flags, u32 max_width, u32 max_height)
+{
+	unsigned int i;
+
+	if (!src || !num_clips) {
+		dst->x1 = 0;
+		dst->x2 = max_width;
+		dst->y1 = 0;
+		dst->y2 = max_height;
+		return true;
+	}
+
+	dst->x1 = ~0;
+	dst->y1 = ~0;
+	dst->x2 = 0;
+	dst->y2 = 0;
+
+	for (i = 0; i < num_clips; i++) {
+		if (flags & DRM_MODE_FB_DIRTY_ANNOTATE_COPY)
+			i++;
+		dst->x1 = min(dst->x1, src[i].x1);
+		dst->x2 = max(dst->x2, src[i].x2);
+		dst->y1 = min(dst->y1, src[i].y1);
+		dst->y2 = max(dst->y2, src[i].y2);
+	}
+
+	if (dst->x2 > max_width || dst->y2 > max_height ||
+	    dst->x1 >= dst->x2 || dst->y1 >= dst->y2) {
+		DRM_DEBUG_KMS("Illegal clip: x1=%u, x2=%u, y1=%u, y2=%u\n",
+			      dst->x1, dst->x2, dst->y1, dst->y2);
+		dst->x1 = 0;
+		dst->y1 = 0;
+		dst->x2 = max_width;
+		dst->y2 = max_height;
+	}
+
+	return (dst->x2 - dst->x1) == max_width &&
+	       (dst->y2 - dst->y1) == max_height;
+}
+EXPORT_SYMBOL(tinydrm_merge_clips);
+
+/**
+ * tinydrm_memcpy - Copy clip buffer
+ * @dst: Destination buffer
+ * @vaddr: Source buffer
+ * @fb: DRM framebuffer
+ * @clip: Clip rectangle area to copy
+ */
+void tinydrm_memcpy(void *dst, void *vaddr, struct drm_framebuffer *fb,
+		    struct drm_clip_rect *clip)
+{
+	unsigned int cpp = drm_format_plane_cpp(fb->format->format, 0);
+	unsigned int pitch = fb->pitches[0];
+	void *src = vaddr + (clip->y1 * pitch) + (clip->x1 * cpp);
+	size_t len = (clip->x2 - clip->x1) * cpp;
+	unsigned int y;
+
+	for (y = clip->y1; y < clip->y2; y++) {
+		memcpy(dst, src, len);
+		src += pitch;
+		dst += len;
+	}
+}
+EXPORT_SYMBOL(tinydrm_memcpy);
+
+/**
+ * tinydrm_swab16 - Swap bytes into clip buffer
+ * @dst: RGB565 destination buffer
+ * @vaddr: RGB565 source buffer
+ * @fb: DRM framebuffer
+ * @clip: Clip rectangle area to copy
+ */
+
+
+/*
+
+FIXME
+
+Doing a memcpy to a temporary buffer before swapping bytes, increases
+framerate by 26%, instead of swapping directly from the source buffer
+which is drm_gem_cma_object->vaddr.
+
+Why is that?
+
+(swapping is needed because Raspberry Pi is Little Endian and doesn't
+have 16-bit SPI support).
+
+# SPI @32MHz
+$ modetest <...> 320x240@RG16 -v
+
+no tmp buffer
+freq: 18.91Hz
+
+tmp buffer
+freq: 23.98Hz
+
+
+*/
+static void *buf;
+
+void tinydrm_swab16(u16 *dst, void *vaddr, struct drm_framebuffer *fb,
+		    struct drm_clip_rect *clip)
+{
+#if 1
+	unsigned int pitch = fb->pitches[0];
+	unsigned int x, y;
+	u16 *src;
+
+	if (!buf)
+		buf = kmalloc(320 * 2, GFP_KERNEL);
+	if (WARN_ON_ONCE(!buf))
+		return;
+
+	for (y = clip->y1; y < clip->y2; y++) {
+		src = vaddr + (y * pitch);
+		src += clip->x1;
+		memcpy(buf, src, (clip->x2 - clip->x1) * 2);
+		src = buf;
+		for (x = clip->x1; x < clip->x2; x++)
+			*dst++ = swab16(*src++);
+	}
+#else
+	unsigned int pitch = fb->pitches[0];
+	unsigned int x, y;
+	u16 *src;
+
+	for (y = clip->y1; y < clip->y2; y++) {
+		src = vaddr + (y * pitch);
+		src += clip->x1;
+		for (x = clip->x1; x < clip->x2; x++)
+			*dst++ = swab16(*src++);
+	}
+#endif
+}
+EXPORT_SYMBOL(tinydrm_swab16);
+
+/**
+ * tinydrm_xrgb8888_to_rgb565 - Convert XRGB8888 to RGB565 clip buffer
+ * @dst: RGB565 destination buffer
+ * @vaddr: XRGB8888 source buffer
+ * @fb: DRM framebuffer
+ * @clip: Clip rectangle area to copy
+ * @swap: Swap bytes
+ *
+ * Drivers can use this function for RGB565 devices that don't natively
+ * support XRGB8888.
+ */
+void tinydrm_xrgb8888_to_rgb565(u16 *dst, void *vaddr,
+				struct drm_framebuffer *fb,
+				struct drm_clip_rect *clip, bool swap)
+{
+	unsigned int pitch = fb->pitches[0];
+	unsigned int x, y;
+	u16 val16;
+	u32 *src;
+
+	for (y = clip->y1; y < clip->y2; y++) {
+		src = vaddr + (y * pitch);
+		src += clip->x1;
+		for (x = clip->x1; x < clip->x2; x++) {
+			val16 = ((*src & 0x00F80000) >> 8) |
+				((*src & 0x0000FC00) >> 5) |
+				((*src & 0x000000F8) >> 3);
+			src++;
+			if (swap)
+				*dst++ = swab16(val16);
+			else
+				*dst++ = val16;
+		}
+	}
+}
+EXPORT_SYMBOL(tinydrm_xrgb8888_to_rgb565);
+
+#ifdef CONFIG_BACKLIGHT_CLASS_DEVICE
+/**
+ * tinydrm_of_find_backlight - Find backlight device in device-tree
+ * @dev: Device
+ *
+ * This function looks for a DT node pointed to by a property named 'backlight'
+ * and uses of_find_backlight_by_node() to get the backlight device.
+ * Additionally if the brightness property is zero, it is set to
+ * max_brightness.
+ *
+ * Returns:
+ * NULL if there's no backlight property.
+ * Error pointer -EPROBE_DEFER if the DT node is found, but no backlight device
+ * is found.
+ * If the backlight device is found, a pointer to the structure is returned.
+ */
+struct backlight_device *tinydrm_of_find_backlight(struct device *dev)
+{
+	struct backlight_device *backlight;
+	struct device_node *np;
+
+	np = of_parse_phandle(dev->of_node, "backlight", 0);
+	if (!np)
+		return NULL;
+
+	backlight = of_find_backlight_by_node(np);
+	of_node_put(np);
+
+	if (!backlight)
+		return ERR_PTR(-EPROBE_DEFER);
+
+	if (!backlight->props.brightness) {
+		backlight->props.brightness = backlight->props.max_brightness;
+		DRM_DEBUG_KMS("Backlight brightness set to %d\n",
+			      backlight->props.brightness);
+	}
+
+	return backlight;
+}
+EXPORT_SYMBOL(tinydrm_of_find_backlight);
+
+/**
+ * tinydrm_enable_backlight - Enable backlight helper
+ * @backlight: Backlight device
+ *
+ * Returns:
+ * Zero on success, negative error code on failure.
+ */
+int tinydrm_enable_backlight(struct backlight_device *backlight)
+{
+	unsigned int old_state;
+	int ret;
+
+	if (!backlight)
+		return 0;
+
+	old_state = backlight->props.state;
+	backlight->props.state &= ~BL_CORE_SUSPENDED;
+	DRM_DEBUG_KMS("Backlight state: 0x%x -> 0x%x\n", old_state,
+		      backlight->props.state);
+
+	ret = backlight_update_status(backlight);
+	if (ret)
+		DRM_ERROR("Failed to enable backlight %d\n", ret);
+
+	return ret;
+}
+EXPORT_SYMBOL(tinydrm_enable_backlight);
+
+/**
+ * tinydrm_disable_backlight - Disable backlight helper
+ * @backlight: Backlight device
+ *
+ * Returns:
+ * Zero on success, negative error code on failure.
+ */
+int tinydrm_disable_backlight(struct backlight_device *backlight)
+{
+	unsigned int old_state;
+	int ret;
+
+	if (!backlight)
+		return 0;
+
+	old_state = backlight->props.state;
+	backlight->props.state |= BL_CORE_SUSPENDED;
+	DRM_DEBUG_KMS("Backlight state: 0x%x -> 0x%x\n", old_state,
+		      backlight->props.state);
+	ret = backlight_update_status(backlight);
+	if (ret)
+		DRM_ERROR("Failed to disable backlight %d\n", ret);
+
+	return ret;
+}
+EXPORT_SYMBOL(tinydrm_disable_backlight);
+#endif
+
+#ifdef CONFIG_SPI
+
+/**
+ * tinydrm_spi_max_transfer_size - Determine max SPI transfer size
+ * @spi: SPI device
+ * @max_len: Maximum buffer size needed (optional)
+ *
+ * This function returns the maximum size to use for SPI transfers. It checks
+ * the SPI master, the optional @max_len and the module parameter spi_max and
+ * returns the smallest.
+ *
+ * Returns:
+ * Maximum size for SPI transfers
+ */
+size_t tinydrm_spi_max_transfer_size(struct spi_device *spi, size_t max_len)
+{
+	size_t ret;
+
+	ret = min(spi_max_transfer_size(spi), spi->master->max_dma_len);
+	if (max_len)
+		ret = min(ret, max_len);
+	if (spi_max)
+		ret = min_t(size_t, ret, spi_max);
+	ret &= ~0x3;
+	if (ret < 4)
+		ret = 4;
+
+	return ret;
+}
+EXPORT_SYMBOL(tinydrm_spi_max_transfer_size);
+
+/**
+ * tinydrm_spi_bpw_supported - Check if bits per word is supported
+ * @spi: SPI device
+ * @bpw: Bits per word
+ *
+ * This function checks to see if the SPI master driver supports @bpw.
+ *
+ * Returns:
+ * True if @bpw is supported, false otherwise.
+ */
+bool tinydrm_spi_bpw_supported(struct spi_device *spi, u8 bpw)
+{
+	u32 bpw_mask = spi->master->bits_per_word_mask;
+
+	if (bpw == 8)
+		return true;
+
+	if (!bpw_mask) {
+		dev_warn_once(&spi->dev,
+			      "bits_per_word_mask not set, assume 8-bit only\n");
+		return false;
+	}
+
+	if (bpw_mask & SPI_BPW_MASK(bpw))
+		return true;
+
+	return false;
+}
+EXPORT_SYMBOL(tinydrm_spi_bpw_supported);
+
+static void
+tinydrm_dbg_spi_print(struct spi_device *spi, struct spi_transfer *tr,
+		      const void *buf, int idx, bool tx)
+{
+	u32 speed_hz = tr->speed_hz ? tr->speed_hz : spi->max_speed_hz;
+	char linebuf[3 * 32];
+
+	hex_dump_to_buffer(buf, tr->len, 16,
+			   DIV_ROUND_UP(tr->bits_per_word, 8),
+			   linebuf, sizeof(linebuf), false);
+
+	printk(KERN_DEBUG
+	       "    tr(%i): speed=%u%s, bpw=%i, len=%u, %s_buf=[%s%s]\n", idx,
+	       speed_hz > 1000000 ? speed_hz / 1000000 : speed_hz / 1000,
+	       speed_hz > 1000000 ? "MHz" : "kHz", tr->bits_per_word, tr->len,
+	       tx ? "tx" : "rx", linebuf, tr->len > 16 ? " ..." : "");
+}
+
+/* called through tinydrm_dbg_spi_message() */
+void _tinydrm_dbg_spi_message(struct spi_device *spi, struct spi_message *m)
+{
+	struct spi_transfer *tmp;
+	struct list_head *pos;
+	int i = 0;
+
+	list_for_each(pos, &m->transfers) {
+		tmp = list_entry(pos, struct spi_transfer, transfer_list);
+
+		if (tmp->tx_buf)
+			tinydrm_dbg_spi_print(spi, tmp, tmp->tx_buf, i, true);
+		if (tmp->rx_buf)
+			tinydrm_dbg_spi_print(spi, tmp, tmp->rx_buf, i, false);
+		i++;
+	}
+}
+EXPORT_SYMBOL(_tinydrm_dbg_spi_message);
+
+/**
+ * tinydrm_spi_transfer - SPI transfer helper
+ * @spi: SPI device
+ * @speed_hz: Override speed (optional)
+ * @header: Optional header transfer
+ * @bpw: Bits per word
+ * @buf: Buffer to transfer
+ * @len: Buffer length
+ *
+ * This SPI transfer helper breaks up the transfer of @buf into chunks which
+ * the SPI master driver can handle. If the machine is Little Endian and the
+ * SPI master driver doesn't support 16 bits per word, it swaps the bytes and
+ * does a 8-bit transfer.
+ * If @header is set, it is prepended to each SPI message.
+ *
+ * Returns:
+ * Zero on success, negative error code on failure.
+ */
+int tinydrm_spi_transfer(struct spi_device *spi, u32 speed_hz,
+			 struct spi_transfer *header, u8 bpw, const void *buf,
+			 size_t len)
+{
+	struct spi_transfer tr = {
+		.bits_per_word = bpw,
+		.speed_hz = speed_hz,
+	};
+	struct spi_message m;
+	u16 *swap_buf = NULL;
+	size_t max_chunk;
+	size_t chunk;
+	int ret = 0;
+
+	if (WARN_ON_ONCE(bpw != 8 && bpw != 16))
+		return -EINVAL;
+
+	max_chunk = tinydrm_spi_max_transfer_size(spi, 0);
+
+	if (drm_debug & DRM_UT_DRIVER)
+		pr_debug("[drm:%s] bpw=%u, max_chunk=%zu, transfers:\n",
+			 __func__, bpw, max_chunk);
+
+	if (bpw == 16 && !tinydrm_spi_bpw_supported(spi, 16)) {
+		tr.bits_per_word = 8;
+		if (tinydrm_machine_little_endian()) {
+			swap_buf = kmalloc(min(len, max_chunk), GFP_KERNEL);
+			if (!swap_buf)
+				return -ENOMEM;
+		}
+	}
+
+	spi_message_init(&m);
+	if (header)
+		spi_message_add_tail(header, &m);
+	spi_message_add_tail(&tr, &m);
+
+	while (len) {
+		chunk = min(len, max_chunk);
+
+		tr.tx_buf = buf;
+		tr.len = chunk;
+
+		if (swap_buf) {
+			const u16 *buf16 = buf;
+			unsigned int i;
+
+			for (i = 0; i < chunk / 2; i++)
+				swap_buf[i] = swab16(buf16[i]);
+
+			tr.tx_buf = swap_buf;
+		}
+
+		buf += chunk;
+		len -= chunk;
+
+		tinydrm_dbg_spi_message(spi, &m);
+		ret = spi_sync(spi, &m);
+		if (ret)
+			return ret;
+	};
+
+	return 0;
+}
+EXPORT_SYMBOL(tinydrm_spi_transfer);
+
+#endif /* CONFIG_SPI */
diff --git a/include/drm/tinydrm/tinydrm-helpers.h b/include/drm/tinydrm/tinydrm-helpers.h
new file mode 100644
index 0000000..78175fe
--- /dev/null
+++ b/include/drm/tinydrm/tinydrm-helpers.h
@@ -0,0 +1,100 @@
+/*
+ * Copyright (C) 2016 Noralf Trønnes
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ */
+
+#ifndef __LINUX_TINYDRM_HELPERS_H
+#define __LINUX_TINYDRM_HELPERS_H
+
+struct backlight_device;
+struct tinydrm_device;
+struct drm_clip_rect;
+struct spi_transfer;
+struct spi_message;
+struct spi_device;
+struct device;
+
+/**
+ * tinydrm_machine_little_endian - Machine is little endian
+ *
+ * Returns:
+ * true if *defined(__LITTLE_ENDIAN)*, false otherwise
+ */
+static inline bool tinydrm_machine_little_endian(void)
+{
+#if defined(__LITTLE_ENDIAN)
+	return true;
+#else
+	return false;
+#endif
+}
+
+bool tinydrm_merge_clips(struct drm_clip_rect *dst,
+			 struct drm_clip_rect *src, unsigned int num_clips,
+			 unsigned int flags, u32 max_width, u32 max_height);
+void tinydrm_memcpy(void *dst, void *vaddr, struct drm_framebuffer *fb,
+		    struct drm_clip_rect *clip);
+void tinydrm_swab16(u16 *dst, void *vaddr, struct drm_framebuffer *fb,
+		    struct drm_clip_rect *clip);
+void tinydrm_xrgb8888_to_rgb565(u16 *dst, void *vaddr,
+				struct drm_framebuffer *fb,
+				struct drm_clip_rect *clip, bool swap);
+
+#ifdef CONFIG_BACKLIGHT_CLASS_DEVICE
+struct backlight_device *tinydrm_of_find_backlight(struct device *dev);
+int tinydrm_enable_backlight(struct backlight_device *backlight);
+int tinydrm_disable_backlight(struct backlight_device *backlight);
+#else
+static inline struct backlight_device *
+tinydrm_of_find_backlight(struct device *dev)
+{
+	return NULL;
+}
+
+static inline int tinydrm_enable_backlight(struct backlight_device *backlight)
+{
+	return 0;
+}
+
+static inline int
+tinydrm_disable_backlight(struct backlight_device *backlight)
+{
+	return 0;
+}
+#endif
+
+size_t tinydrm_spi_max_transfer_size(struct spi_device *spi, size_t max_len);
+bool tinydrm_spi_bpw_supported(struct spi_device *spi, u8 bpw);
+int tinydrm_spi_transfer(struct spi_device *spi, u32 speed_hz,
+			 struct spi_transfer *header, u8 bpw, const void *buf,
+			 size_t len);
+void _tinydrm_dbg_spi_message(struct spi_device *spi, struct spi_message *m);
+
+#ifdef DEBUG
+/**
+ * tinydrm_dbg_spi_message - Dump SPI message
+ * @spi: SPI device
+ * @m: SPI message
+ *
+ * Dumps info about the transfers in a SPI message including buffer content.
+ * DEBUG has to be defined for this function to be enabled alongside setting
+ * the DRM_UT_DRIVER bit of &drm_debug.
+ */
+static inline void tinydrm_dbg_spi_message(struct spi_device *spi,
+					   struct spi_message *m)
+{
+	if (drm_debug & DRM_UT_DRIVER)
+		_tinydrm_dbg_spi_message(spi, m);
+}
+#else
+static inline void tinydrm_dbg_spi_message(struct spi_device *spi,
+					   struct spi_message *m)
+{
+}
+#endif /* DEBUG */
+
+#endif /* __LINUX_TINYDRM_HELPERS_H */
-- 
2.10.2

_______________________________________________
dri-devel mailing list
dri-devel@lists.freedesktop.org
https://lists.freedesktop.org/mailman/listinfo/dri-devel

Re: [PATCH 5/9] drm/tinydrm: Add helper functions

[Daniel Vetter]

On Sun, Jan 22, 2017 at 07:11:13PM +0100, Noralf Trønnes wrote:
> Add common functionality needed by many tinydrm drivers.
> 
> Signed-off-by: Noralf Trønnes <noralf@tronnes.org>

Bunch of comments below, all optional.
-Daniel

> ---
>  Documentation/gpu/drm-kms-helpers.rst          |   6 +
>  drivers/gpu/drm/tinydrm/core/Makefile          |   2 +-
>  drivers/gpu/drm/tinydrm/core/tinydrm-helpers.c | 490 +++++++++++++++++++++++++
>  include/drm/tinydrm/tinydrm-helpers.h          | 100 +++++
>  4 files changed, 597 insertions(+), 1 deletion(-)
>  create mode 100644 drivers/gpu/drm/tinydrm/core/tinydrm-helpers.c
>  create mode 100644 include/drm/tinydrm/tinydrm-helpers.h
> 
> diff --git a/Documentation/gpu/drm-kms-helpers.rst b/Documentation/gpu/drm-kms-helpers.rst
> index a86bd7f..be07e76 100644
> --- a/Documentation/gpu/drm-kms-helpers.rst
> +++ b/Documentation/gpu/drm-kms-helpers.rst
> @@ -287,3 +287,9 @@ tinydrm Helper Reference
>  
>  .. kernel-doc:: drivers/gpu/drm/tinydrm/core/tinydrm-pipe.c
>     :export:
> +
> +.. kernel-doc:: include/drm/tinydrm/tinydrm-helpers.h
> +   :internal:
> +
> +.. kernel-doc:: drivers/gpu/drm/tinydrm/core/tinydrm-helpers.c
> +   :export:
> diff --git a/drivers/gpu/drm/tinydrm/core/Makefile b/drivers/gpu/drm/tinydrm/core/Makefile
> index 4f14a0f..fb221e6 100644
> --- a/drivers/gpu/drm/tinydrm/core/Makefile
> +++ b/drivers/gpu/drm/tinydrm/core/Makefile
> @@ -1,3 +1,3 @@
> -tinydrm-y := tinydrm-core.o tinydrm-pipe.o
> +tinydrm-y := tinydrm-core.o tinydrm-pipe.o tinydrm-helpers.o
>  
>  obj-$(CONFIG_DRM_TINYDRM) += tinydrm.o
> diff --git a/drivers/gpu/drm/tinydrm/core/tinydrm-helpers.c b/drivers/gpu/drm/tinydrm/core/tinydrm-helpers.c
> new file mode 100644
> index 0000000..fc02e01
> --- /dev/null
> +++ b/drivers/gpu/drm/tinydrm/core/tinydrm-helpers.c
> @@ -0,0 +1,490 @@
> +/*
> + * Copyright (C) 2016 Noralf Trønnes
> + *
> + * This program is free software; you can redistribute it and/or modify
> + * it under the terms of the GNU General Public License as published by
> + * the Free Software Foundation; either version 2 of the License, or
> + * (at your option) any later version.
> + */
> +
> +#include <drm/tinydrm/tinydrm.h>
> +#include <drm/tinydrm/tinydrm-helpers.h>
> +#include <linux/backlight.h>
> +#include <linux/pm.h>
> +#include <linux/spi/spi.h>
> +#include <linux/swab.h>
> +
> +static unsigned int spi_max;
> +module_param(spi_max, uint, 0400);
> +MODULE_PARM_DESC(spi_max, "Set a lower SPI max transfer size");
> +
> +/**
> + * tinydrm_merge_clips - Merge clip rectangles
> + * @dst: Destination clip rectangle
> + * @src: Source clip rectangle(s)
> + * @num_clips: Number of @src clip rectangles
> + * @flags: Dirty fb ioctl flags
> + * @max_width: Maximum width of @dst
> + * @max_height: Maximum height of @dst
> + *
> + * This function merges @src clip rectangle(s) into @dst. If @src is NULL,
> + * @max_width and @min_width is used to set a full @dst clip rectangle.
> + *
> + * Returns:
> + * true if it's a full clip, false otherwise
> + */
> +bool tinydrm_merge_clips(struct drm_clip_rect *dst,
> +			 struct drm_clip_rect *src, unsigned int num_clips,
> +			 unsigned int flags, u32 max_width, u32 max_height)
> +{
> +	unsigned int i;
> +
> +	if (!src || !num_clips) {
> +		dst->x1 = 0;
> +		dst->x2 = max_width;
> +		dst->y1 = 0;
> +		dst->y2 = max_height;
> +		return true;
> +	}
> +
> +	dst->x1 = ~0;
> +	dst->y1 = ~0;
> +	dst->x2 = 0;
> +	dst->y2 = 0;
> +
> +	for (i = 0; i < num_clips; i++) {
> +		if (flags & DRM_MODE_FB_DIRTY_ANNOTATE_COPY)
> +			i++;
> +		dst->x1 = min(dst->x1, src[i].x1);
> +		dst->x2 = max(dst->x2, src[i].x2);
> +		dst->y1 = min(dst->y1, src[i].y1);
> +		dst->y2 = max(dst->y2, src[i].y2);
> +	}
> +
> +	if (dst->x2 > max_width || dst->y2 > max_height ||
> +	    dst->x1 >= dst->x2 || dst->y1 >= dst->y2) {
> +		DRM_DEBUG_KMS("Illegal clip: x1=%u, x2=%u, y1=%u, y2=%u\n",
> +			      dst->x1, dst->x2, dst->y1, dst->y2);
> +		dst->x1 = 0;
> +		dst->y1 = 0;
> +		dst->x2 = max_width;
> +		dst->y2 = max_height;
> +	}
> +
> +	return (dst->x2 - dst->x1) == max_width &&
> +	       (dst->y2 - dst->y1) == max_height;
> +}
> +EXPORT_SYMBOL(tinydrm_merge_clips);

Argh, the drm_clip_rect vs. drm_rect confusion strikes again :(

> +
> +/**
> + * tinydrm_memcpy - Copy clip buffer
> + * @dst: Destination buffer
> + * @vaddr: Source buffer
> + * @fb: DRM framebuffer
> + * @clip: Clip rectangle area to copy
> + */
> +void tinydrm_memcpy(void *dst, void *vaddr, struct drm_framebuffer *fb,
> +		    struct drm_clip_rect *clip)
> +{
> +	unsigned int cpp = drm_format_plane_cpp(fb->format->format, 0);
> +	unsigned int pitch = fb->pitches[0];
> +	void *src = vaddr + (clip->y1 * pitch) + (clip->x1 * cpp);
> +	size_t len = (clip->x2 - clip->x1) * cpp;
> +	unsigned int y;
> +
> +	for (y = clip->y1; y < clip->y2; y++) {
> +		memcpy(dst, src, len);
> +		src += pitch;
> +		dst += len;
> +	}
> +}
> +EXPORT_SYMBOL(tinydrm_memcpy);
> +
> +/**
> + * tinydrm_swab16 - Swap bytes into clip buffer
> + * @dst: RGB565 destination buffer
> + * @vaddr: RGB565 source buffer
> + * @fb: DRM framebuffer
> + * @clip: Clip rectangle area to copy
> + */
> +
> +
> +/*
> +
> +FIXME
> +
> +Doing a memcpy to a temporary buffer before swapping bytes, increases
> +framerate by 26%, instead of swapping directly from the source buffer
> +which is drm_gem_cma_object->vaddr.
> +
> +Why is that?
> +
> +(swapping is needed because Raspberry Pi is Little Endian and doesn't
> +have 16-bit SPI support).
> +
> +# SPI @32MHz
> +$ modetest <...> 320x240@RG16 -v
> +
> +no tmp buffer
> +freq: 18.91Hz
> +
> +tmp buffer
> +freq: 23.98Hz
> +
> +
> +*/
> +static void *buf;
> +
> +void tinydrm_swab16(u16 *dst, void *vaddr, struct drm_framebuffer *fb,
> +		    struct drm_clip_rect *clip)
> +{
> +#if 1
> +	unsigned int pitch = fb->pitches[0];
> +	unsigned int x, y;
> +	u16 *src;
> +
> +	if (!buf)
> +		buf = kmalloc(320 * 2, GFP_KERNEL);
> +	if (WARN_ON_ONCE(!buf))
> +		return;
> +
> +	for (y = clip->y1; y < clip->y2; y++) {
> +		src = vaddr + (y * pitch);
> +		src += clip->x1;
> +		memcpy(buf, src, (clip->x2 - clip->x1) * 2);
> +		src = buf;
> +		for (x = clip->x1; x < clip->x2; x++)
> +			*dst++ = swab16(*src++);
> +	}
> +#else
> +	unsigned int pitch = fb->pitches[0];
> +	unsigned int x, y;
> +	u16 *src;
> +
> +	for (y = clip->y1; y < clip->y2; y++) {
> +		src = vaddr + (y * pitch);
> +		src += clip->x1;
> +		for (x = clip->x1; x < clip->x2; x++)
> +			*dst++ = swab16(*src++);
> +	}
> +#endif
> +}
> +EXPORT_SYMBOL(tinydrm_swab16);
> +
> +/**
> + * tinydrm_xrgb8888_to_rgb565 - Convert XRGB8888 to RGB565 clip buffer
> + * @dst: RGB565 destination buffer
> + * @vaddr: XRGB8888 source buffer
> + * @fb: DRM framebuffer
> + * @clip: Clip rectangle area to copy
> + * @swap: Swap bytes
> + *
> + * Drivers can use this function for RGB565 devices that don't natively
> + * support XRGB8888.
> + */
> +void tinydrm_xrgb8888_to_rgb565(u16 *dst, void *vaddr,
> +				struct drm_framebuffer *fb,
> +				struct drm_clip_rect *clip, bool swap)
> +{
> +	unsigned int pitch = fb->pitches[0];
> +	unsigned int x, y;
> +	u16 val16;
> +	u32 *src;
> +
> +	for (y = clip->y1; y < clip->y2; y++) {
> +		src = vaddr + (y * pitch);
> +		src += clip->x1;
> +		for (x = clip->x1; x < clip->x2; x++) {
> +			val16 = ((*src & 0x00F80000) >> 8) |
> +				((*src & 0x0000FC00) >> 5) |
> +				((*src & 0x000000F8) >> 3);
> +			src++;
> +			if (swap)
> +				*dst++ = swab16(val16);
> +			else
> +				*dst++ = val16;
> +		}
> +	}
> +}
> +EXPORT_SYMBOL(tinydrm_xrgb8888_to_rgb565);

I wonder whether the above would make sense in drm core as some kind of fb
helpers. But we can do that once there's a clear need.

> +
> +#ifdef CONFIG_BACKLIGHT_CLASS_DEVICE
> +/**
> + * tinydrm_of_find_backlight - Find backlight device in device-tree
> + * @dev: Device
> + *
> + * This function looks for a DT node pointed to by a property named 'backlight'
> + * and uses of_find_backlight_by_node() to get the backlight device.
> + * Additionally if the brightness property is zero, it is set to
> + * max_brightness.
> + *
> + * Returns:
> + * NULL if there's no backlight property.
> + * Error pointer -EPROBE_DEFER if the DT node is found, but no backlight device
> + * is found.
> + * If the backlight device is found, a pointer to the structure is returned.
> + */
> +struct backlight_device *tinydrm_of_find_backlight(struct device *dev)
> +{
> +	struct backlight_device *backlight;
> +	struct device_node *np;
> +
> +	np = of_parse_phandle(dev->of_node, "backlight", 0);
> +	if (!np)
> +		return NULL;
> +
> +	backlight = of_find_backlight_by_node(np);
> +	of_node_put(np);
> +
> +	if (!backlight)
> +		return ERR_PTR(-EPROBE_DEFER);
> +
> +	if (!backlight->props.brightness) {
> +		backlight->props.brightness = backlight->props.max_brightness;
> +		DRM_DEBUG_KMS("Backlight brightness set to %d\n",
> +			      backlight->props.brightness);
> +	}

I
> +
> +	return backlight;
> +}
> +EXPORT_SYMBOL(tinydrm_of_find_backlight);
> +
> +/**
> + * tinydrm_enable_backlight - Enable backlight helper
> + * @backlight: Backlight device
> + *
> + * Returns:
> + * Zero on success, negative error code on failure.
> + */
> +int tinydrm_enable_backlight(struct backlight_device *backlight)
> +{
> +	unsigned int old_state;
> +	int ret;
> +
> +	if (!backlight)
> +		return 0;
> +
> +	old_state = backlight->props.state;
> +	backlight->props.state &= ~BL_CORE_SUSPENDED;
> +	DRM_DEBUG_KMS("Backlight state: 0x%x -> 0x%x\n", old_state,
> +		      backlight->props.state);
> +
> +	ret = backlight_update_status(backlight);
> +	if (ret)
> +		DRM_ERROR("Failed to enable backlight %d\n", ret);
> +
> +	return ret;
> +}
> +EXPORT_SYMBOL(tinydrm_enable_backlight);
> +
> +/**
> + * tinydrm_disable_backlight - Disable backlight helper
> + * @backlight: Backlight device
> + *
> + * Returns:
> + * Zero on success, negative error code on failure.
> + */
> +int tinydrm_disable_backlight(struct backlight_device *backlight)
> +{
> +	unsigned int old_state;
> +	int ret;
> +
> +	if (!backlight)
> +		return 0;
> +
> +	old_state = backlight->props.state;
> +	backlight->props.state |= BL_CORE_SUSPENDED;
> +	DRM_DEBUG_KMS("Backlight state: 0x%x -> 0x%x\n", old_state,
> +		      backlight->props.state);
> +	ret = backlight_update_status(backlight);
> +	if (ret)
> +		DRM_ERROR("Failed to disable backlight %d\n", ret);
> +
> +	return ret;
> +}
> +EXPORT_SYMBOL(tinydrm_disable_backlight);
> +#endif
> +
> +#ifdef CONFIG_SPI
> +
> +/**
> + * tinydrm_spi_max_transfer_size - Determine max SPI transfer size
> + * @spi: SPI device
> + * @max_len: Maximum buffer size needed (optional)
> + *
> + * This function returns the maximum size to use for SPI transfers. It checks
> + * the SPI master, the optional @max_len and the module parameter spi_max and
> + * returns the smallest.
> + *
> + * Returns:
> + * Maximum size for SPI transfers
> + */
> +size_t tinydrm_spi_max_transfer_size(struct spi_device *spi, size_t max_len)
> +{
> +	size_t ret;
> +
> +	ret = min(spi_max_transfer_size(spi), spi->master->max_dma_len);
> +	if (max_len)
> +		ret = min(ret, max_len);
> +	if (spi_max)
> +		ret = min_t(size_t, ret, spi_max);
> +	ret &= ~0x3;
> +	if (ret < 4)
> +		ret = 4;
> +
> +	return ret;
> +}
> +EXPORT_SYMBOL(tinydrm_spi_max_transfer_size);
> +
> +/**
> + * tinydrm_spi_bpw_supported - Check if bits per word is supported
> + * @spi: SPI device
> + * @bpw: Bits per word
> + *
> + * This function checks to see if the SPI master driver supports @bpw.
> + *
> + * Returns:
> + * True if @bpw is supported, false otherwise.
> + */
> +bool tinydrm_spi_bpw_supported(struct spi_device *spi, u8 bpw)
> +{
> +	u32 bpw_mask = spi->master->bits_per_word_mask;
> +
> +	if (bpw == 8)
> +		return true;
> +
> +	if (!bpw_mask) {
> +		dev_warn_once(&spi->dev,
> +			      "bits_per_word_mask not set, assume 8-bit only\n");
> +		return false;
> +	}
> +
> +	if (bpw_mask & SPI_BPW_MASK(bpw))
> +		return true;
> +
> +	return false;
> +}
> +EXPORT_SYMBOL(tinydrm_spi_bpw_supported);
> +
> +static void
> +tinydrm_dbg_spi_print(struct spi_device *spi, struct spi_transfer *tr,
> +		      const void *buf, int idx, bool tx)
> +{
> +	u32 speed_hz = tr->speed_hz ? tr->speed_hz : spi->max_speed_hz;
> +	char linebuf[3 * 32];
> +
> +	hex_dump_to_buffer(buf, tr->len, 16,
> +			   DIV_ROUND_UP(tr->bits_per_word, 8),
> +			   linebuf, sizeof(linebuf), false);
> +
> +	printk(KERN_DEBUG
> +	       "    tr(%i): speed=%u%s, bpw=%i, len=%u, %s_buf=[%s%s]\n", idx,
> +	       speed_hz > 1000000 ? speed_hz / 1000000 : speed_hz / 1000,
> +	       speed_hz > 1000000 ? "MHz" : "kHz", tr->bits_per_word, tr->len,
> +	       tx ? "tx" : "rx", linebuf, tr->len > 16 ? " ..." : "");
> +}
> +
> +/* called through tinydrm_dbg_spi_message() */
> +void _tinydrm_dbg_spi_message(struct spi_device *spi, struct spi_message *m)
> +{
> +	struct spi_transfer *tmp;
> +	struct list_head *pos;
> +	int i = 0;
> +
> +	list_for_each(pos, &m->transfers) {
> +		tmp = list_entry(pos, struct spi_transfer, transfer_list);
> +
> +		if (tmp->tx_buf)
> +			tinydrm_dbg_spi_print(spi, tmp, tmp->tx_buf, i, true);
> +		if (tmp->rx_buf)
> +			tinydrm_dbg_spi_print(spi, tmp, tmp->rx_buf, i, false);
> +		i++;
> +	}
> +}
> +EXPORT_SYMBOL(_tinydrm_dbg_spi_message);
> +
> +/**
> + * tinydrm_spi_transfer - SPI transfer helper
> + * @spi: SPI device
> + * @speed_hz: Override speed (optional)
> + * @header: Optional header transfer
> + * @bpw: Bits per word
> + * @buf: Buffer to transfer
> + * @len: Buffer length
> + *
> + * This SPI transfer helper breaks up the transfer of @buf into chunks which
> + * the SPI master driver can handle. If the machine is Little Endian and the
> + * SPI master driver doesn't support 16 bits per word, it swaps the bytes and
> + * does a 8-bit transfer.
> + * If @header is set, it is prepended to each SPI message.
> + *
> + * Returns:
> + * Zero on success, negative error code on failure.
> + */
> +int tinydrm_spi_transfer(struct spi_device *spi, u32 speed_hz,
> +			 struct spi_transfer *header, u8 bpw, const void *buf,
> +			 size_t len)
> +{
> +	struct spi_transfer tr = {
> +		.bits_per_word = bpw,
> +		.speed_hz = speed_hz,
> +	};
> +	struct spi_message m;
> +	u16 *swap_buf = NULL;
> +	size_t max_chunk;
> +	size_t chunk;
> +	int ret = 0;
> +
> +	if (WARN_ON_ONCE(bpw != 8 && bpw != 16))
> +		return -EINVAL;
> +
> +	max_chunk = tinydrm_spi_max_transfer_size(spi, 0);
> +
> +	if (drm_debug & DRM_UT_DRIVER)
> +		pr_debug("[drm:%s] bpw=%u, max_chunk=%zu, transfers:\n",
> +			 __func__, bpw, max_chunk);
> +
> +	if (bpw == 16 && !tinydrm_spi_bpw_supported(spi, 16)) {
> +		tr.bits_per_word = 8;
> +		if (tinydrm_machine_little_endian()) {
> +			swap_buf = kmalloc(min(len, max_chunk), GFP_KERNEL);
> +			if (!swap_buf)
> +				return -ENOMEM;
> +		}
> +	}
> +
> +	spi_message_init(&m);
> +	if (header)
> +		spi_message_add_tail(header, &m);
> +	spi_message_add_tail(&tr, &m);
> +
> +	while (len) {
> +		chunk = min(len, max_chunk);
> +
> +		tr.tx_buf = buf;
> +		tr.len = chunk;
> +
> +		if (swap_buf) {
> +			const u16 *buf16 = buf;
> +			unsigned int i;
> +
> +			for (i = 0; i < chunk / 2; i++)
> +				swap_buf[i] = swab16(buf16[i]);
> +
> +			tr.tx_buf = swap_buf;
> +		}
> +
> +		buf += chunk;
> +		len -= chunk;
> +
> +		tinydrm_dbg_spi_message(spi, &m);
> +		ret = spi_sync(spi, &m);
> +		if (ret)
> +			return ret;
> +	};
> +
> +	return 0;
> +}
> +EXPORT_SYMBOL(tinydrm_spi_transfer);

Hm, might be worth it to try and move the spi helpers into the spi core
code. But imo better to merge this now and move later on, than delay
merging tinydrm.

> +
> +#endif /* CONFIG_SPI */
> diff --git a/include/drm/tinydrm/tinydrm-helpers.h b/include/drm/tinydrm/tinydrm-helpers.h
> new file mode 100644
> index 0000000..78175fe
> --- /dev/null
> +++ b/include/drm/tinydrm/tinydrm-helpers.h
> @@ -0,0 +1,100 @@
> +/*
> + * Copyright (C) 2016 Noralf Trønnes
> + *
> + * This program is free software; you can redistribute it and/or modify
> + * it under the terms of the GNU General Public License as published by
> + * the Free Software Foundation; either version 2 of the License, or
> + * (at your option) any later version.
> + */
> +
> +#ifndef __LINUX_TINYDRM_HELPERS_H
> +#define __LINUX_TINYDRM_HELPERS_H
> +
> +struct backlight_device;
> +struct tinydrm_device;
> +struct drm_clip_rect;
> +struct spi_transfer;
> +struct spi_message;
> +struct spi_device;
> +struct device;
> +
> +/**
> + * tinydrm_machine_little_endian - Machine is little endian
> + *
> + * Returns:
> + * true if *defined(__LITTLE_ENDIAN)*, false otherwise
> + */
> +static inline bool tinydrm_machine_little_endian(void)
> +{
> +#if defined(__LITTLE_ENDIAN)
> +	return true;
> +#else
> +	return false;
> +#endif
> +}
> +
> +bool tinydrm_merge_clips(struct drm_clip_rect *dst,
> +			 struct drm_clip_rect *src, unsigned int num_clips,
> +			 unsigned int flags, u32 max_width, u32 max_height);
> +void tinydrm_memcpy(void *dst, void *vaddr, struct drm_framebuffer *fb,
> +		    struct drm_clip_rect *clip);
> +void tinydrm_swab16(u16 *dst, void *vaddr, struct drm_framebuffer *fb,
> +		    struct drm_clip_rect *clip);
> +void tinydrm_xrgb8888_to_rgb565(u16 *dst, void *vaddr,
> +				struct drm_framebuffer *fb,
> +				struct drm_clip_rect *clip, bool swap);
> +
> +#ifdef CONFIG_BACKLIGHT_CLASS_DEVICE
> +struct backlight_device *tinydrm_of_find_backlight(struct device *dev);
> +int tinydrm_enable_backlight(struct backlight_device *backlight);
> +int tinydrm_disable_backlight(struct backlight_device *backlight);
> +#else
> +static inline struct backlight_device *
> +tinydrm_of_find_backlight(struct device *dev)
> +{
> +	return NULL;
> +}
> +
> +static inline int tinydrm_enable_backlight(struct backlight_device *backlight)
> +{
> +	return 0;
> +}
> +
> +static inline int
> +tinydrm_disable_backlight(struct backlight_device *backlight)
> +{
> +	return 0;
> +}
> +#endif
> +
> +size_t tinydrm_spi_max_transfer_size(struct spi_device *spi, size_t max_len);
> +bool tinydrm_spi_bpw_supported(struct spi_device *spi, u8 bpw);
> +int tinydrm_spi_transfer(struct spi_device *spi, u32 speed_hz,
> +			 struct spi_transfer *header, u8 bpw, const void *buf,
> +			 size_t len);
> +void _tinydrm_dbg_spi_message(struct spi_device *spi, struct spi_message *m);
> +
> +#ifdef DEBUG
> +/**
> + * tinydrm_dbg_spi_message - Dump SPI message
> + * @spi: SPI device
> + * @m: SPI message
> + *
> + * Dumps info about the transfers in a SPI message including buffer content.
> + * DEBUG has to be defined for this function to be enabled alongside setting
> + * the DRM_UT_DRIVER bit of &drm_debug.
> + */
> +static inline void tinydrm_dbg_spi_message(struct spi_device *spi,
> +					   struct spi_message *m)
> +{
> +	if (drm_debug & DRM_UT_DRIVER)
> +		_tinydrm_dbg_spi_message(spi, m);
> +}
> +#else
> +static inline void tinydrm_dbg_spi_message(struct spi_device *spi,
> +					   struct spi_message *m)
> +{
> +}
> +#endif /* DEBUG */
> +
> +#endif /* __LINUX_TINYDRM_HELPERS_H */
> -- 
> 2.10.2
> 
> _______________________________________________
> dri-devel mailing list
> dri-devel@lists.freedesktop.org
> https://lists.freedesktop.org/mailman/listinfo/dri-devel

-- 
Daniel Vetter
Software Engineer, Intel Corporation
http://blog.ffwll.ch

[PATCH 6/9] drm/tinydrm: Add MIPI DBI support

[Noralf Trønnes]

Add support for MIPI DBI compatible controllers.
Interface type C option 1 and 3 are supported (SPI).

Signed-off-by: Noralf Trønnes <noralf@tronnes.org>
---
 Documentation/gpu/drm-kms-helpers.rst |   12 +
 drivers/gpu/drm/tinydrm/Kconfig       |    3 +
 drivers/gpu/drm/tinydrm/Makefile      |    3 +
 drivers/gpu/drm/tinydrm/mipi-dbi.c    | 1005 +++++++++++++++++++++++++++++++++
 include/drm/tinydrm/mipi-dbi.h        |  107 ++++
 5 files changed, 1130 insertions(+)
 create mode 100644 drivers/gpu/drm/tinydrm/mipi-dbi.c
 create mode 100644 include/drm/tinydrm/mipi-dbi.h

diff --git a/Documentation/gpu/drm-kms-helpers.rst b/Documentation/gpu/drm-kms-helpers.rst
index be07e76..bd18734 100644
--- a/Documentation/gpu/drm-kms-helpers.rst
+++ b/Documentation/gpu/drm-kms-helpers.rst
@@ -293,3 +293,15 @@ tinydrm Helper Reference
 
 .. kernel-doc:: drivers/gpu/drm/tinydrm/core/tinydrm-helpers.c
    :export:
+
+MIPI DBI Helper Reference
+-------------------------
+
+.. kernel-doc:: drivers/gpu/drm/tinydrm/mipi-dbi.c
+   :doc: overview
+
+.. kernel-doc:: include/drm/tinydrm/mipi-dbi.h
+   :internal:
+
+.. kernel-doc:: drivers/gpu/drm/tinydrm/mipi-dbi.c
+   :export:
diff --git a/drivers/gpu/drm/tinydrm/Kconfig b/drivers/gpu/drm/tinydrm/Kconfig
index ffb873f..128d2f3 100644
--- a/drivers/gpu/drm/tinydrm/Kconfig
+++ b/drivers/gpu/drm/tinydrm/Kconfig
@@ -6,3 +6,6 @@ menuconfig DRM_TINYDRM
 	help
 	  Choose this option if you have a tinydrm supported display.
 	  If M is selected the module will be called tinydrm.
+
+config TINYDRM_MIPI_DBI
+	tristate
diff --git a/drivers/gpu/drm/tinydrm/Makefile b/drivers/gpu/drm/tinydrm/Makefile
index 7476ed1..fe5d4c6 100644
--- a/drivers/gpu/drm/tinydrm/Makefile
+++ b/drivers/gpu/drm/tinydrm/Makefile
@@ -1 +1,4 @@
 obj-$(CONFIG_DRM_TINYDRM)		+= core/
+
+# Controllers
+obj-$(CONFIG_TINYDRM_MIPI_DBI)		+= mipi-dbi.o
diff --git a/drivers/gpu/drm/tinydrm/mipi-dbi.c b/drivers/gpu/drm/tinydrm/mipi-dbi.c
new file mode 100644
index 0000000..5ded299
--- /dev/null
+++ b/drivers/gpu/drm/tinydrm/mipi-dbi.c
@@ -0,0 +1,1005 @@
+/*
+ * MIPI Display Bus Interface (DBI) LCD controller support
+ *
+ * Copyright 2016 Noralf Trønnes
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ */
+
+#include <drm/tinydrm/mipi-dbi.h>
+#include <drm/tinydrm/tinydrm-helpers.h>
+#include <linux/debugfs.h>
+#include <linux/dma-buf.h>
+#include <linux/gpio/consumer.h>
+#include <linux/module.h>
+#include <linux/regulator/consumer.h>
+#include <linux/spi/spi.h>
+#include <video/mipi_display.h>
+
+#define MIPI_DBI_MAX_SPI_READ_SPEED 2000000 /* 2MHz */
+
+#define DCS_POWER_MODE_DISPLAY			BIT(2)
+#define DCS_POWER_MODE_DISPLAY_NORMAL_MODE	BIT(3)
+#define DCS_POWER_MODE_SLEEP_MODE		BIT(4)
+#define DCS_POWER_MODE_PARTIAL_MODE		BIT(5)
+#define DCS_POWER_MODE_IDLE_MODE		BIT(6)
+#define DCS_POWER_MODE_RESERVED_MASK		(BIT(0) | BIT(1) | BIT(7))
+
+/**
+ * DOC: overview
+ *
+ * This library provides helpers for MIPI Display Bus Interface (DBI)
+ * compatible display controllers.
+ *
+ * Many controllers for tiny lcd displays are MIPI compliant and can use this
+ * library. If a controller uses registers 0x2A and 0x2B to set the area to
+ * update and uses register 0x2C to write to frame memory, it is most likely
+ * MIPI compliant.
+ *
+ * Only MIPI Type 1 displays are supported since a full frame memory is needed.
+ *
+ * There are 3 MIPI DBI implementation types:
+ *
+ * A. Motorola 6800 type parallel bus
+ *
+ * B. Intel 8080 type parallel bus
+ *
+ * C. SPI type with 3 options:
+ *
+ *    1. 9-bit with the Data/Command signal as the ninth bit
+ *    2. Same as above except it's sent as 16 bits
+ *    3. 8-bit with the Data/Command signal as a separate D/CX pin
+ *
+ * Currently mipi_dbi only supports Type C options 1 and 3 with
+ * mipi_dbi_spi_init().
+ */
+
+#define MIPI_DBI_DEBUG_COMMAND(cmd, data, len) \
+({ \
+	if (!len) \
+		DRM_DEBUG_DRIVER("cmd=%02x\n", cmd); \
+	else if (len <= 32) \
+		DRM_DEBUG_DRIVER("cmd=%02x, par=%*ph\n", cmd, len, data); \
+	else \
+		DRM_DEBUG_DRIVER("cmd=%02x, len=%zu\n", cmd, len); \
+})
+
+static const u8 mipi_dbi_dcs_read_commands[] = {
+	MIPI_DCS_GET_DISPLAY_ID,
+	MIPI_DCS_GET_RED_CHANNEL,
+	MIPI_DCS_GET_GREEN_CHANNEL,
+	MIPI_DCS_GET_BLUE_CHANNEL,
+	MIPI_DCS_GET_DISPLAY_STATUS,
+	MIPI_DCS_GET_POWER_MODE,
+	MIPI_DCS_GET_ADDRESS_MODE,
+	MIPI_DCS_GET_PIXEL_FORMAT,
+	MIPI_DCS_GET_DISPLAY_MODE,
+	MIPI_DCS_GET_SIGNAL_MODE,
+	MIPI_DCS_GET_DIAGNOSTIC_RESULT,
+	MIPI_DCS_READ_MEMORY_START,
+	MIPI_DCS_READ_MEMORY_CONTINUE,
+	MIPI_DCS_GET_SCANLINE,
+	MIPI_DCS_GET_DISPLAY_BRIGHTNESS,
+	MIPI_DCS_GET_CONTROL_DISPLAY,
+	MIPI_DCS_GET_POWER_SAVE,
+	MIPI_DCS_GET_CABC_MIN_BRIGHTNESS,
+	MIPI_DCS_READ_DDB_START,
+	MIPI_DCS_READ_DDB_CONTINUE,
+	0, /* sentinel */
+};
+
+static bool mipi_dbi_command_is_read(struct mipi_dbi *mipi, u8 cmd)
+{
+	unsigned int i;
+
+	if (!mipi->read_commands)
+		return false;
+
+	for (i = 0; i < 0xff; i++) {
+		if (!mipi->read_commands[i])
+			return false;
+		if (cmd == mipi->read_commands[i])
+			return true;
+	}
+
+	return false;
+}
+
+/**
+ * mipi_dbi_command_read - MIPI DCS read command
+ * @mipi: MIPI structure
+ * @cmd: Command
+ * @val: Value read
+ *
+ * Send MIPI DCS read command to the controller.
+ *
+ * Returns:
+ * Zero on success, negative error code on failure.
+ */
+int mipi_dbi_command_read(struct mipi_dbi *mipi, u8 cmd, u8 *val)
+{
+	if (!mipi->read_commands)
+		return -EACCES;
+
+	if (!mipi_dbi_command_is_read(mipi, cmd))
+		return -EINVAL;
+
+	return mipi_dbi_command_buf(mipi, cmd, val, 1);
+}
+EXPORT_SYMBOL(mipi_dbi_command_read);
+
+/**
+ * mipi_dbi_command_buf - MIPI DCS command with parameter(s) in an array
+ * @mipi: MIPI structure
+ * @cmd: Command
+ * @data: Parameter buffer
+ * @len: Buffer length
+ *
+ * Returns:
+ * Zero on success, negative error code on failure.
+ */
+int mipi_dbi_command_buf(struct mipi_dbi *mipi, u8 cmd, u8 *data, size_t len)
+{
+	int ret;
+
+	mutex_lock(&mipi->cmdlock);
+	ret = mipi->command(mipi, cmd, data, len);
+	mutex_unlock(&mipi->cmdlock);
+
+	return ret;
+}
+EXPORT_SYMBOL(mipi_dbi_command_buf);
+
+static int mipi_dbi_buf_copy(void *dst, struct drm_framebuffer *fb,
+				struct drm_clip_rect *clip, bool swap)
+{
+	struct drm_gem_cma_object *cma_obj = drm_fb_cma_get_gem_obj(fb, 0);
+	struct dma_buf_attachment *import_attach = cma_obj->base.import_attach;
+	struct drm_format_name_buf format_name;
+	void *src = cma_obj->vaddr;
+	int ret = 0;
+
+	if (import_attach) {
+		ret = dma_buf_begin_cpu_access(import_attach->dmabuf,
+					       DMA_FROM_DEVICE);
+		if (ret)
+			return ret;
+	}
+
+	switch (fb->format->format) {
+	case DRM_FORMAT_RGB565:
+		if (swap)
+			tinydrm_swab16(dst, src, fb, clip);
+		else
+			tinydrm_memcpy(dst, src, fb, clip);
+		break;
+	case DRM_FORMAT_XRGB8888:
+		tinydrm_xrgb8888_to_rgb565(dst, src, fb, clip, swap);
+		break;
+	default:
+		dev_err_once(fb->dev->dev, "Format is not supported: %s\n",
+			     drm_get_format_name(fb->format->format,
+						 &format_name));
+		return -EINVAL;
+	}
+
+	if (import_attach)
+		ret = dma_buf_end_cpu_access(import_attach->dmabuf,
+					     DMA_FROM_DEVICE);
+	return ret;
+}
+
+static int mipi_dbi_fb_dirty(struct drm_framebuffer *fb,
+			     struct drm_file *file_priv,
+			     unsigned int flags, unsigned int color,
+			     struct drm_clip_rect *clips,
+			     unsigned int num_clips)
+{
+	struct drm_gem_cma_object *cma_obj = drm_fb_cma_get_gem_obj(fb, 0);
+	struct tinydrm_device *tdev = fb->dev->dev_private;
+	struct mipi_dbi *mipi = mipi_dbi_from_tinydrm(tdev);
+	bool swap = mipi->swap_bytes;
+	struct drm_clip_rect clip;
+	int ret = 0;
+	bool full;
+	void *tr;
+
+	mutex_lock(&tdev->dirty_lock);
+
+	if (!mipi->enabled)
+		goto out_unlock;
+
+	/* fbdev can flush even when we're not interested */
+	if (tdev->pipe.plane.fb != fb)
+		goto out_unlock;
+
+	full = tinydrm_merge_clips(&clip, clips, num_clips, flags,
+				   fb->width, fb->height);
+
+	DRM_DEBUG("Flushing [FB:%d] x1=%u, x2=%u, y1=%u, y2=%u\n", fb->base.id,
+		  clip.x1, clip.x2, clip.y1, clip.y2);
+
+	if (!mipi->dc || !full || swap ||
+	    fb->format->format == DRM_FORMAT_XRGB8888) {
+		tr = mipi->tx_buf;
+		ret = mipi_dbi_buf_copy(mipi->tx_buf, fb, &clip, swap);
+		if (ret)
+			goto out_unlock;
+	} else {
+		tr = cma_obj->vaddr;
+	}
+
+	mipi_dbi_command(mipi, MIPI_DCS_SET_COLUMN_ADDRESS,
+			 (clip.x1 >> 8) & 0xFF, clip.x1 & 0xFF,
+			 (clip.x2 >> 8) & 0xFF, (clip.x2 - 1) & 0xFF);
+	mipi_dbi_command(mipi, MIPI_DCS_SET_PAGE_ADDRESS,
+			 (clip.y1 >> 8) & 0xFF, clip.y1 & 0xFF,
+			 (clip.y2 >> 8) & 0xFF, (clip.y2 - 1) & 0xFF);
+
+	ret = mipi_dbi_command_buf(mipi, MIPI_DCS_WRITE_MEMORY_START, tr,
+				(clip.x2 - clip.x1) * (clip.y2 - clip.y1) * 2);
+
+out_unlock:
+	mutex_unlock(&tdev->dirty_lock);
+
+	if (ret)
+		dev_err_once(fb->dev->dev, "Failed to update display %d\n",
+			     ret);
+
+	return ret;
+}
+
+static const struct drm_framebuffer_funcs mipi_dbi_fb_funcs = {
+	.destroy	= drm_fb_cma_destroy,
+	.create_handle	= drm_fb_cma_create_handle,
+	.dirty		= mipi_dbi_fb_dirty,
+};
+
+/**
+ * mipi_dbi_pipe_enable - MIPI DBI pipe enable helper
+ * @pipe: Display pipe
+ * @crtc_state: CRTC state
+ *
+ * This function enables backlight. Drivers can use this as their
+ * &drm_simple_display_pipe_funcs->enable callback.
+ */
+void mipi_dbi_pipe_enable(struct drm_simple_display_pipe *pipe,
+			  struct drm_crtc_state *crtc_state)
+{
+	struct tinydrm_device *tdev = pipe_to_tinydrm(pipe);
+	struct mipi_dbi *mipi = mipi_dbi_from_tinydrm(tdev);
+	struct drm_framebuffer *fb = pipe->plane.fb;
+
+	DRM_DEBUG_KMS("\n");
+
+	mipi->enabled = true;
+	if (fb)
+		fb->funcs->dirty(fb, NULL, 0, 0, NULL, 0);
+
+	tinydrm_enable_backlight(mipi->backlight);
+}
+EXPORT_SYMBOL(mipi_dbi_pipe_enable);
+
+static void mipi_dbi_blank(struct mipi_dbi *mipi)
+{
+	struct drm_device *drm = mipi->tinydrm.drm;
+	u16 height = drm->mode_config.min_height;
+	u16 width = drm->mode_config.min_width;
+	size_t len = width * height * 2;
+
+	memset(mipi->tx_buf, 0, len);
+
+	mipi_dbi_command(mipi, MIPI_DCS_SET_COLUMN_ADDRESS, 0, 0,
+			 (width >> 8) & 0xFF, (width - 1) & 0xFF);
+	mipi_dbi_command(mipi, MIPI_DCS_SET_PAGE_ADDRESS, 0, 0,
+			 (height >> 8) & 0xFF, (height - 1) & 0xFF);
+	mipi_dbi_command_buf(mipi, MIPI_DCS_WRITE_MEMORY_START,
+			     (u8 *)mipi->tx_buf, len);
+}
+
+/**
+ * mipi_dbi_pipe_disable - MIPI DBI pipe disable helper
+ * @pipe: Display pipe
+ *
+ * This function disables backlight if present or if not the
+ * display memory is blanked. Drivers can use this as their
+ * &drm_simple_display_pipe_funcs->disable callback.
+ */
+void mipi_dbi_pipe_disable(struct drm_simple_display_pipe *pipe)
+{
+	struct tinydrm_device *tdev = pipe_to_tinydrm(pipe);
+	struct mipi_dbi *mipi = mipi_dbi_from_tinydrm(tdev);
+
+	DRM_DEBUG_KMS("\n");
+
+	mipi->enabled = false;
+
+	if (mipi->backlight)
+		tinydrm_disable_backlight(mipi->backlight);
+	else
+		mipi_dbi_blank(mipi);
+}
+EXPORT_SYMBOL(mipi_dbi_pipe_disable);
+
+static const uint32_t mipi_dbi_formats[] = {
+	DRM_FORMAT_RGB565,
+	DRM_FORMAT_XRGB8888,
+};
+
+/**
+ * mipi_dbi_init - MIPI DBI initialization
+ * @dev: Parent device
+ * @mipi: &mipi_dbi structure to initialize
+ * @pipe_funcs: Display pipe functions
+ * @driver: DRM driver
+ * @mode: Display mode
+ * @rotation: Initial rotation in degrees Counter Clock Wise
+ *
+ * This function initializes a &mipi_dbi structure and it's underlying
+ * @tinydrm_device. It also sets up the display pipeline.
+ *
+ * Supported formats: Native RGB565 and emulated XRGB8888.
+ *
+ * Objects created by this function will be automatically freed on driver
+ * detach (devres).
+ *
+ * Returns:
+ * Zero on success, negative error code on failure.
+ */
+int mipi_dbi_init(struct device *dev, struct mipi_dbi *mipi,
+		  const struct drm_simple_display_pipe_funcs *pipe_funcs,
+		  struct drm_driver *driver,
+		  const struct drm_display_mode *mode, unsigned int rotation)
+{
+	size_t bufsize = mode->vdisplay * mode->hdisplay * sizeof(u16);
+	struct tinydrm_device *tdev = &mipi->tinydrm;
+	int ret;
+
+	if (!mipi->command)
+		return -EINVAL;
+
+	mutex_init(&mipi->cmdlock);
+
+	mipi->tx_buf = devm_kmalloc(dev, bufsize, GFP_KERNEL);
+	if (!mipi->tx_buf)
+		return -ENOMEM;
+
+	ret = devm_tinydrm_init(dev, tdev, &mipi_dbi_fb_funcs, driver);
+	if (ret)
+		return ret;
+
+	/* TODO: Maybe add DRM_MODE_CONNECTOR_SPI */
+	ret = tinydrm_display_pipe_init(tdev, pipe_funcs,
+					DRM_MODE_CONNECTOR_VIRTUAL,
+					mipi_dbi_formats,
+					ARRAY_SIZE(mipi_dbi_formats), mode,
+					rotation);
+	if (ret)
+		return ret;
+
+	tdev->drm->mode_config.preferred_depth = 16;
+	mipi->rotation = rotation;
+
+	drm_mode_config_reset(tdev->drm);
+
+	DRM_DEBUG_KMS("preferred_depth=%u, rotation = %u\n",
+		      tdev->drm->mode_config.preferred_depth, rotation);
+
+	return 0;
+}
+EXPORT_SYMBOL(mipi_dbi_init);
+
+/**
+ * mipi_dbi_hw_reset - Hardware reset of controller
+ * @mipi: MIPI DBI structure
+ *
+ * Reset controller if the &mipi_dbi->reset gpio is set.
+ */
+void mipi_dbi_hw_reset(struct mipi_dbi *mipi)
+{
+	if (!mipi->reset)
+		return;
+
+	gpiod_set_value_cansleep(mipi->reset, 0);
+	msleep(20);
+	gpiod_set_value_cansleep(mipi->reset, 1);
+	msleep(120);
+}
+EXPORT_SYMBOL(mipi_dbi_hw_reset);
+
+/**
+ * mipi_dbi_display_is_on - Check if display is on
+ * @mipi: MIPI DBI structure
+ *
+ * This function checks the Power Mode register (if readable) to see if
+ * display output is turned on. This can be used to see if the bootloader
+ * has already turned on the display avoiding flicker when the pipeline is
+ * enabled.
+ *
+ * Returns:
+ * true if the display can be verified to be on, false otherwise.
+ */
+bool mipi_dbi_display_is_on(struct mipi_dbi *mipi)
+{
+	u8 val;
+
+	if (mipi_dbi_command_read(mipi, MIPI_DCS_GET_POWER_MODE, &val))
+		return false;
+
+	val &= ~DCS_POWER_MODE_RESERVED_MASK;
+
+	if (val != (DCS_POWER_MODE_DISPLAY |
+	    DCS_POWER_MODE_DISPLAY_NORMAL_MODE | DCS_POWER_MODE_SLEEP_MODE))
+		return false;
+
+	DRM_DEBUG_DRIVER("Display is ON\n");
+
+	return true;
+}
+EXPORT_SYMBOL(mipi_dbi_display_is_on);
+
+#ifdef CONFIG_SPI
+
+/*
+ * Many controllers have a max speed of 10MHz, but can be pushed way beyond
+ * that. Increase reliability by running pixel data at max speed and the rest
+ * at 10MHz, preventing transfer glitches from messing up the init settings.
+ */
+static u32 mipi_dbi_spi_cmd_max_speed(struct spi_device *spi, size_t len)
+{
+	if (len > 64)
+		return 0; /* use default */
+
+	return min_t(u32, 10000000, spi->max_speed_hz);
+}
+
+/*
+ * MIPI DBI Type C Option 1
+ *
+ * If the SPI controller doesn't have 9 bits per word support,
+ * use blocks of 9 bytes to send 8x 9-bit words using a 8-bit SPI transfer.
+ * Pad partial blocks with MIPI_DCS_NOP (zero).
+ * This is how the D/C bit (x) is added:
+ *     x7654321
+ *     0x765432
+ *     10x76543
+ *     210x7654
+ *     3210x765
+ *     43210x76
+ *     543210x7
+ *     6543210x
+ *     76543210
+ */
+
+static int mipi_dbi_spi1e_transfer(struct mipi_dbi *mipi, int dc,
+				   const void *buf, size_t len,
+				   unsigned int bpw)
+{
+	bool swap_bytes = (bpw == 16 && tinydrm_machine_little_endian());
+	size_t chunk, max_chunk = mipi->tx_buf9_len;
+	struct spi_device *spi = mipi->spi;
+	struct spi_transfer tr = {
+		.tx_buf = mipi->tx_buf9,
+		.bits_per_word = 8,
+	};
+	struct spi_message m;
+	const u8 *src = buf;
+	int i, ret;
+	u8 *dst;
+
+	if (drm_debug & DRM_UT_DRIVER)
+		pr_debug("[drm:%s] dc=%d, max_chunk=%zu, transfers:\n",
+			 __func__, dc, max_chunk);
+
+	tr.speed_hz = mipi_dbi_spi_cmd_max_speed(spi, len);
+	spi_message_init_with_transfers(&m, &tr, 1);
+
+	if (!dc) {
+		if (WARN_ON_ONCE(len != 1))
+			return -EINVAL;
+
+		/* Command: pad no-op's (zeroes) at beginning of block */
+		dst = mipi->tx_buf9;
+		memset(dst, 0, 9);
+		dst[8] = *src;
+		tr.len = 9;
+
+		tinydrm_dbg_spi_message(spi, &m);
+
+		return spi_sync(spi, &m);
+	}
+
+	/* max with room for adding one bit per byte */
+	max_chunk = max_chunk / 9 * 8;
+	/* but no bigger than len */
+	max_chunk = min(max_chunk, len);
+	/* 8 byte blocks */
+	max_chunk = max_t(size_t, 8, max_chunk & ~0x7);
+
+	while (len) {
+		size_t added = 0;
+
+		chunk = min(len, max_chunk);
+		len -= chunk;
+		dst = mipi->tx_buf9;
+
+		if (chunk < 8) {
+			u8 val, carry = 0;
+
+			/* Data: pad no-op's (zeroes) at end of block */
+			memset(dst, 0, 9);
+
+			if (swap_bytes) {
+				for (i = 1; i < (chunk + 1); i++) {
+					val = src[1];
+					*dst++ = carry | BIT(8 - i) | (val >> i);
+					carry = val << (8 - i);
+					i++;
+					val = src[0];
+					*dst++ = carry | BIT(8 - i) | (val >> i);
+					carry = val << (8 - i);
+					src += 2;
+				}
+				*dst++ = carry;
+			} else {
+				for (i = 1; i < (chunk + 1); i++) {
+					val = *src++;
+					*dst++ = carry | BIT(8 - i) | (val >> i);
+					carry = val << (8 - i);
+				}
+				*dst++ = carry;
+			}
+
+			chunk = 8;
+			added = 1;
+		} else {
+			for (i = 0; i < chunk; i += 8) {
+				if (swap_bytes) {
+					*dst++ =                 BIT(7) | (src[1] >> 1);
+					*dst++ = (src[1] << 7) | BIT(6) | (src[0] >> 2);
+					*dst++ = (src[0] << 6) | BIT(5) | (src[3] >> 3);
+					*dst++ = (src[3] << 5) | BIT(4) | (src[2] >> 4);
+					*dst++ = (src[2] << 4) | BIT(3) | (src[5] >> 5);
+					*dst++ = (src[5] << 3) | BIT(2) | (src[4] >> 6);
+					*dst++ = (src[4] << 2) | BIT(1) | (src[7] >> 7);
+					*dst++ = (src[7] << 1) | BIT(0);
+					*dst++ = src[6];
+				} else {
+					*dst++ =                 BIT(7) | (src[0] >> 1);
+					*dst++ = (src[0] << 7) | BIT(6) | (src[1] >> 2);
+					*dst++ = (src[1] << 6) | BIT(5) | (src[2] >> 3);
+					*dst++ = (src[2] << 5) | BIT(4) | (src[3] >> 4);
+					*dst++ = (src[3] << 4) | BIT(3) | (src[4] >> 5);
+					*dst++ = (src[4] << 3) | BIT(2) | (src[5] >> 6);
+					*dst++ = (src[5] << 2) | BIT(1) | (src[6] >> 7);
+					*dst++ = (src[6] << 1) | BIT(0);
+					*dst++ = src[7];
+				}
+
+				src += 8;
+				added++;
+			}
+		}
+
+		tr.len = chunk + added;
+
+		tinydrm_dbg_spi_message(spi, &m);
+		ret = spi_sync(spi, &m);
+		if (ret)
+			return ret;
+	};
+
+	return 0;
+}
+
+static int mipi_dbi_spi1_transfer(struct mipi_dbi *mipi, int dc,
+				  const void *buf, size_t len,
+				  unsigned int bpw)
+{
+	struct spi_device *spi = mipi->spi;
+	struct spi_transfer tr = {
+		.bits_per_word = 9,
+	};
+	const u16 *src16 = buf;
+	const u8 *src8 = buf;
+	struct spi_message m;
+	size_t max_chunk;
+	u16 *dst16;
+	int ret;
+
+	if (!tinydrm_spi_bpw_supported(spi, 9))
+		return mipi_dbi_spi1e_transfer(mipi, dc, buf, len, bpw);
+
+	tr.speed_hz = mipi_dbi_spi_cmd_max_speed(spi, len);
+	max_chunk = mipi->tx_buf9_len;
+	dst16 = mipi->tx_buf9;
+
+	if (drm_debug & DRM_UT_DRIVER)
+		pr_debug("[drm:%s] dc=%d, max_chunk=%zu, transfers:\n",
+			 __func__, dc, max_chunk);
+
+	max_chunk = min(max_chunk / 2, len);
+
+	spi_message_init_with_transfers(&m, &tr, 1);
+	tr.tx_buf = dst16;
+
+	while (len) {
+		size_t chunk = min(len, max_chunk);
+		unsigned int i;
+
+		if (bpw == 16 && tinydrm_machine_little_endian()) {
+			for (i = 0; i < (chunk * 2); i += 2) {
+				dst16[i]     = *src16 >> 8;
+				dst16[i + 1] = *src16++ & 0xFF;
+				if (dc) {
+					dst16[i]     |= 0x0100;
+					dst16[i + 1] |= 0x0100;
+				}
+			}
+		} else {
+			for (i = 0; i < chunk; i++) {
+				dst16[i] = *src8++;
+				if (dc)
+					dst16[i] |= 0x0100;
+			}
+		}
+
+		tr.len = chunk;
+		len -= chunk;
+
+		tinydrm_dbg_spi_message(spi, &m);
+		ret = spi_sync(spi, &m);
+		if (ret)
+			return ret;
+	};
+
+	return 0;
+}
+
+static int mipi_dbi_typec1_command(struct mipi_dbi *mipi, u8 cmd,
+				   u8 *parameters, size_t num)
+{
+	unsigned int bpw = (cmd == MIPI_DCS_WRITE_MEMORY_START) ? 16 : 8;
+	int ret;
+
+	if (mipi_dbi_command_is_read(mipi, cmd))
+		return -ENOTSUPP;
+
+	MIPI_DBI_DEBUG_COMMAND(cmd, parameters, num);
+
+	ret = mipi_dbi_spi1_transfer(mipi, 0, &cmd, 1, 8);
+	if (ret || !num)
+		return ret;
+
+	return mipi_dbi_spi1_transfer(mipi, 1, parameters, num, bpw);
+}
+
+/* MIPI DBI Type C Option 3 */
+
+static int mipi_dbi_typec3_command_read(struct mipi_dbi *mipi, u8 cmd,
+					u8 *data, size_t len)
+{
+	struct spi_device *spi = mipi->spi;
+	u32 speed_hz = min_t(u32, MIPI_DBI_MAX_SPI_READ_SPEED,
+			     spi->max_speed_hz / 2);
+	struct spi_transfer tr[2] = {
+		{
+			.speed_hz = speed_hz,
+			.tx_buf = &cmd,
+			.len = 1,
+		}, {
+			.speed_hz = speed_hz,
+			.len = len,
+		},
+	};
+	struct spi_message m;
+	u8 *buf;
+	int ret;
+
+	if (!len)
+		return -EINVAL;
+
+	/*
+	 * Support non-standard 24-bit and 32-bit Nokia read commands which
+	 * start with a dummy clock, so we need to read an extra byte.
+	 */
+	if (cmd == MIPI_DCS_GET_DISPLAY_ID ||
+	    cmd == MIPI_DCS_GET_DISPLAY_STATUS) {
+		if (!(len == 3 || len == 4))
+			return -EINVAL;
+
+		tr[1].len = len + 1;
+	}
+
+	buf = kmalloc(tr[1].len, GFP_KERNEL);
+	if (!buf)
+		return -ENOMEM;
+
+	tr[1].rx_buf = buf;
+	gpiod_set_value_cansleep(mipi->dc, 0);
+
+	spi_message_init_with_transfers(&m, tr, ARRAY_SIZE(tr));
+	ret = spi_sync(spi, &m);
+	if (ret)
+		goto err_free;
+
+	tinydrm_dbg_spi_message(spi, &m);
+
+	if (tr[1].len == len) {
+		memcpy(data, buf, len);
+	} else {
+		unsigned int i;
+
+		for (i = 0; i < len; i++)
+			data[i] = (buf[i] << 1) | !!(buf[i + 1] & BIT(7));
+	}
+
+	MIPI_DBI_DEBUG_COMMAND(cmd, data, len);
+
+err_free:
+	kfree(buf);
+
+	return ret;
+}
+
+static int mipi_dbi_typec3_command(struct mipi_dbi *mipi, u8 cmd,
+				   u8 *par, size_t num)
+{
+	struct spi_device *spi = mipi->spi;
+	unsigned int bpw = 8;
+	u32 speed_hz;
+	int ret;
+
+	if (mipi_dbi_command_is_read(mipi, cmd))
+		return mipi_dbi_typec3_command_read(mipi, cmd, par, num);
+
+	MIPI_DBI_DEBUG_COMMAND(cmd, par, num);
+
+	gpiod_set_value_cansleep(mipi->dc, 0);
+	speed_hz = mipi_dbi_spi_cmd_max_speed(spi, 1);
+	ret = tinydrm_spi_transfer(spi, speed_hz, NULL, 8, &cmd, 1);
+	if (ret || !num)
+		return ret;
+
+	if (cmd == MIPI_DCS_WRITE_MEMORY_START && !mipi->swap_bytes)
+		bpw = 16;
+
+	gpiod_set_value_cansleep(mipi->dc, 1);
+	speed_hz = mipi_dbi_spi_cmd_max_speed(spi, num);
+
+	return tinydrm_spi_transfer(spi, speed_hz, NULL, bpw, par, num);
+}
+
+/**
+ * mipi_dbi_spi_init - Initialize MIPI DBI SPI interfaced controller
+ * @spi: SPI device
+ * @dc: D/C gpio (optional)
+ * @mipi: &mipi_dbi structure to initialize
+ * @pipe_funcs: Display pipe functions
+ * @driver: DRM driver
+ * @mode: Display mode
+ * @rotation: Initial rotation in degrees Counter Clock Wise
+ *
+ * This function sets &mipi_dbi->command, enables &mipi->read_commands for the
+ * usual read commands and initializes @mipi using mipi_dbi_init().
+ *
+ * If @dc is set, a Type C Option 3 interface is assumed, if not
+ * Type C Option 1.
+ *
+ * If the SPI master driver doesn't support the necessary bits per word,
+ * the following transformation is used:
+ *
+ * - 9-bit: reorder buffer as 9x 8-bit words, padded with no-op command.
+ * - 16-bit: if big endian send as 8-bit, if little endian swap bytes
+ *
+ * Returns:
+ * Zero on success, negative error code on failure.
+ */
+int mipi_dbi_spi_init(struct spi_device *spi, struct mipi_dbi *mipi,
+		      struct gpio_desc *dc,
+		      const struct drm_simple_display_pipe_funcs *pipe_funcs,
+		      struct drm_driver *driver,
+		      const struct drm_display_mode *mode,
+		      unsigned int rotation)
+{
+	size_t tx_size = tinydrm_spi_max_transfer_size(spi, 0);
+	struct device *dev = &spi->dev;
+	int ret;
+
+	if (tx_size < 16) {
+		DRM_ERROR("SPI transmit buffer too small: %zu\n", tx_size);
+		return -EINVAL;
+	}
+
+	/*
+	 * Even though it's not the SPI device that does DMA (the master does),
+	 * the dma mask is necessary for the dma_alloc_wc() in
+	 * drm_gem_cma_create(). The dma_addr returned will be a physical
+	 * adddress which might be different from the bus address, but this is
+	 * not a problem since the address will not be used.
+	 * The virtual address is used in the transfer and the SPI core
+	 * re-maps it on the SPI master device using the DMA streaming API
+	 * (spi_map_buf()).
+	 */
+	if (!dev->coherent_dma_mask) {
+		ret = dma_coerce_mask_and_coherent(dev, DMA_BIT_MASK(32));
+		if (ret) {
+			dev_warn(dev, "Failed to set dma mask %d\n", ret);
+			return ret;
+		}
+	}
+
+	mipi->spi = spi;
+	mipi->read_commands = mipi_dbi_dcs_read_commands;
+
+	if (dc) {
+		mipi->command = mipi_dbi_typec3_command;
+		mipi->dc = dc;
+		if (tinydrm_machine_little_endian() &&
+		    !tinydrm_spi_bpw_supported(spi, 16))
+			mipi->swap_bytes = true;
+	} else {
+		mipi->command = mipi_dbi_typec1_command;
+		mipi->tx_buf9_len = tx_size;
+		mipi->tx_buf9 = devm_kmalloc(dev, tx_size, GFP_KERNEL);
+		if (!mipi->tx_buf9)
+			return -ENOMEM;
+	}
+
+	return mipi_dbi_init(dev, mipi, pipe_funcs, driver, mode, rotation);
+}
+EXPORT_SYMBOL(mipi_dbi_spi_init);
+
+#endif /* CONFIG_SPI */
+
+#ifdef CONFIG_DEBUG_FS
+
+static ssize_t mipi_dbi_debugfs_command_write(struct file *file,
+					      const char __user *ubuf,
+					      size_t count, loff_t *ppos)
+{
+	struct seq_file *m = file->private_data;
+	struct mipi_dbi *mipi = m->private;
+	u8 val, cmd, parameters[64];
+	char *buf, *pos, *token;
+	unsigned int i;
+	int ret;
+
+	buf = memdup_user_nul(ubuf, count);
+	if (IS_ERR(buf))
+		return PTR_ERR(buf);
+
+	/* strip trailing whitespace */
+	for (i = count - 1; i > 0; i--)
+		if (isspace(buf[i]))
+			buf[i] = '\0';
+		else
+			break;
+	i = 0;
+	pos = buf;
+	while (pos) {
+		token = strsep(&pos, " ");
+		if (!token) {
+			ret = -EINVAL;
+			goto err_free;
+		}
+
+		ret = kstrtou8(token, 16, &val);
+		if (ret < 0)
+			goto err_free;
+
+		if (token == buf)
+			cmd = val;
+		else
+			parameters[i++] = val;
+
+		if (i == 64) {
+			ret = -E2BIG;
+			goto err_free;
+		}
+	}
+
+	ret = mipi_dbi_command_buf(mipi, cmd, parameters, i);
+
+err_free:
+	kfree(buf);
+
+	return ret < 0 ? ret : count;
+}
+
+static int mipi_dbi_debugfs_command_show(struct seq_file *m, void *unused)
+{
+	struct mipi_dbi *mipi = m->private;
+	u8 cmd, val[4];
+	size_t len, i;
+	int ret;
+
+	for (cmd = 0; cmd < 255; cmd++) {
+		if (!mipi_dbi_command_is_read(mipi, cmd))
+			continue;
+
+		switch (cmd) {
+		case MIPI_DCS_READ_MEMORY_START:
+		case MIPI_DCS_READ_MEMORY_CONTINUE:
+			len = 2;
+			break;
+		case MIPI_DCS_GET_DISPLAY_ID:
+			len = 3;
+			break;
+		case MIPI_DCS_GET_DISPLAY_STATUS:
+			len = 4;
+			break;
+		default:
+			len = 1;
+			break;
+		}
+
+		seq_printf(m, "%02x: ", cmd);
+		ret = mipi_dbi_command_buf(mipi, cmd, val, len);
+		if (ret) {
+			seq_puts(m, "XX\n");
+			continue;
+		}
+
+		for (i = 0; i < len; i++)
+			seq_printf(m, "%02x", val[i]);
+		seq_puts(m, "\n");
+	}
+
+	return 0;
+}
+
+static int mipi_dbi_debugfs_command_open(struct inode *inode,
+					 struct file *file)
+{
+	return single_open(file, mipi_dbi_debugfs_command_show,
+			   inode->i_private);
+}
+
+static const struct file_operations mipi_dbi_debugfs_command_fops = {
+	.owner = THIS_MODULE,
+	.open = mipi_dbi_debugfs_command_open,
+	.read = seq_read,
+	.llseek = seq_lseek,
+	.release = single_release,
+	.write = mipi_dbi_debugfs_command_write,
+};
+
+static const struct drm_info_list mipi_dbi_debugfs_list[] = {
+	{ "fb",   drm_fb_cma_debugfs_show, 0 },
+};
+
+/**
+ * mipi_dbi_debugfs_init - Create debugfs entries
+ * @minor: DRM minor
+ *
+ * This function creates a 'command' debugfs file for sending commands to the
+ * controller or getting the read command values.
+ * Drivers can use this as their &drm_driver->debugfs_init callback.
+ *
+ * Returns:
+ * Zero on success, negative error code on failure.
+ */
+int mipi_dbi_debugfs_init(struct drm_minor *minor)
+{
+	struct tinydrm_device *tdev = minor->dev->dev_private;
+	struct mipi_dbi *mipi = mipi_dbi_from_tinydrm(tdev);
+	umode_t mode = S_IFREG | S_IWUSR;
+
+	if (mipi->read_commands)
+		mode |= S_IRUGO;
+	debugfs_create_file("command", mode, minor->debugfs_root, mipi,
+			    &mipi_dbi_debugfs_command_fops);
+
+	return drm_debugfs_create_files(mipi_dbi_debugfs_list,
+					ARRAY_SIZE(mipi_dbi_debugfs_list),
+					minor->debugfs_root, minor);
+}
+EXPORT_SYMBOL(mipi_dbi_debugfs_init);
+
+#endif
+
+MODULE_LICENSE("GPL");
diff --git a/include/drm/tinydrm/mipi-dbi.h b/include/drm/tinydrm/mipi-dbi.h
new file mode 100644
index 0000000..d137b16
--- /dev/null
+++ b/include/drm/tinydrm/mipi-dbi.h
@@ -0,0 +1,107 @@
+/*
+ * MIPI Display Bus Interface (DBI) LCD controller support
+ *
+ * Copyright 2016 Noralf Trønnes
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ */
+
+#ifndef __LINUX_MIPI_DBI_H
+#define __LINUX_MIPI_DBI_H
+
+#include <drm/tinydrm/tinydrm.h>
+
+struct spi_device;
+struct gpio_desc;
+struct regulator;
+
+/**
+ * struct mipi_dbi - MIPI DBI controller
+ * @tinydrm: tinydrm base
+ * @spi: SPI device
+ * @enabled: Pipeline is enabled
+ * @cmdlock: Command lock
+ * @command: Bus specific callback executing commands.
+ * @read_commands: Array of read commands terminated by a zero entry.
+ *                 Reading is disabled if this is NULL.
+ * @dc: Optional D/C gpio.
+ * @tx_buf: Buffer used for transfer (copy clip rect area)
+ * @tx_buf9: Buffer used for Option 1 9-bit conversion
+ * @tx_buf9_len: Size of tx_buf9.
+ * @swap_bytes: Swap bytes in buffer before transfer
+ * @reset: Optional reset gpio
+ * @rotation: initial rotation in degrees Counter Clock Wise
+ * @backlight: backlight device (optional)
+ * @regulator: power regulator (optional)
+ */
+struct mipi_dbi {
+	struct tinydrm_device tinydrm;
+	struct spi_device *spi;
+	bool enabled;
+	struct mutex cmdlock;
+	int (*command)(struct mipi_dbi *mipi, u8 cmd, u8 *param, size_t num);
+	const u8 *read_commands;
+	struct gpio_desc *dc;
+	u16 *tx_buf;
+	void *tx_buf9;
+	size_t tx_buf9_len;
+	bool swap_bytes;
+	struct gpio_desc *reset;
+	unsigned int rotation;
+	struct backlight_device *backlight;
+	struct regulator *regulator;
+};
+
+static inline struct mipi_dbi *
+mipi_dbi_from_tinydrm(struct tinydrm_device *tdev)
+{
+	return container_of(tdev, struct mipi_dbi, tinydrm);
+}
+
+int mipi_dbi_spi_init(struct spi_device *spi, struct mipi_dbi *mipi,
+		      struct gpio_desc *dc,
+		      const struct drm_simple_display_pipe_funcs *pipe_funcs,
+		      struct drm_driver *driver,
+		      const struct drm_display_mode *mode,
+		      unsigned int rotation);
+int mipi_dbi_init(struct device *dev, struct mipi_dbi *mipi,
+		  const struct drm_simple_display_pipe_funcs *pipe_funcs,
+		  struct drm_driver *driver,
+		  const struct drm_display_mode *mode, unsigned int rotation);
+void mipi_dbi_pipe_enable(struct drm_simple_display_pipe *pipe,
+			  struct drm_crtc_state *crtc_state);
+void mipi_dbi_pipe_disable(struct drm_simple_display_pipe *pipe);
+void mipi_dbi_hw_reset(struct mipi_dbi *mipi);
+bool mipi_dbi_display_is_on(struct mipi_dbi *mipi);
+
+int mipi_dbi_command_read(struct mipi_dbi *mipi, u8 cmd, u8 *val);
+int mipi_dbi_command_buf(struct mipi_dbi *mipi, u8 cmd, u8 *data, size_t len);
+
+/**
+ * mipi_dbi_command - MIPI DCS command with optional parameter(s)
+ * @mipi: MIPI structure
+ * @cmd: Command
+ * @seq...: Optional parameter(s)
+ *
+ * Send MIPI DCS command to the controller. Use mipi_dbi_command_read() for
+ * get/read.
+ *
+ * Returns:
+ * Zero on success, negative error code on failure.
+ */
+#define mipi_dbi_command(mipi, cmd, seq...) \
+({ \
+	u8 d[] = { seq }; \
+	mipi_dbi_command_buf(mipi, cmd, d, ARRAY_SIZE(d)); \
+})
+
+#ifdef CONFIG_DEBUG_FS
+int mipi_dbi_debugfs_init(struct drm_minor *minor);
+#else
+#define mipi_dbi_debugfs_init		NULL
+#endif
+
+#endif /* __LINUX_MIPI_DBI_H */
-- 
2.10.2

_______________________________________________
dri-devel mailing list
dri-devel@lists.freedesktop.org
https://lists.freedesktop.org/mailman/listinfo/dri-devel

[PATCH 7/9] of: Add vendor prefix for Multi-Inno

[Noralf Trønnes]

Multi-Inno Technology Co.,Ltd is a Hong Kong based company offering
LCD, LCD module products and complete panel solutions.

Signed-off-by: Noralf Trønnes <noralf@tronnes.org>
---
 Documentation/devicetree/bindings/vendor-prefixes.txt | 1 +
 1 file changed, 1 insertion(+)

diff --git a/Documentation/devicetree/bindings/vendor-prefixes.txt b/Documentation/devicetree/bindings/vendor-prefixes.txt
index c7624ae..95188cc 100644
--- a/Documentation/devicetree/bindings/vendor-prefixes.txt
+++ b/Documentation/devicetree/bindings/vendor-prefixes.txt
@@ -192,6 +192,7 @@ mpl	MPL AG
 mqmaker	mqmaker Inc.
 msi	Micro-Star International Co. Ltd.
 mti	Imagination Technologies Ltd. (formerly MIPS Technologies Inc.)
+multi-inno	Multi-Inno Technology Co.,Ltd
 mundoreader	Mundo Reader S.L.
 murata	Murata Manufacturing Co., Ltd.
 mxicy	Macronix International Co., Ltd.
-- 
2.10.2

_______________________________________________
dri-devel mailing list
dri-devel@lists.freedesktop.org
https://lists.freedesktop.org/mailman/listinfo/dri-devel

Re: [PATCH 7/9] of: Add vendor prefix for Multi-Inno

[Rob Herring]

On Sun, Jan 22, 2017 at 07:11:15PM +0100, Noralf Trønnes wrote:
> Multi-Inno Technology Co.,Ltd is a Hong Kong based company offering
> LCD, LCD module products and complete panel solutions.
> 
> Signed-off-by: Noralf Trønnes <noralf-L59+Z2yzLopAfugRpC6u6w@public.gmane.org>
> ---
>  Documentation/devicetree/bindings/vendor-prefixes.txt | 1 +
>  1 file changed, 1 insertion(+)

Acked-by: Rob Herring <robh-DgEjT+Ai2ygdnm+yROfE0A@public.gmane.org>
--
To unsubscribe from this list: send the line "unsubscribe devicetree" in
the body of a message to majordomo-u79uwXL29TY76Z2rM5mHXA@public.gmane.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html

[PATCH 8/9] dt-bindings: Add Multi-Inno MI0283QT binding

[Noralf Trønnes]

Add device-tree binding documentation for the MI0283QT display panel.

Signed-off-by: Noralf Trønnes <noralf@tronnes.org>
---

Datasheet: https://cdn-shop.adafruit.com/datasheets/MI0283QT-11+V1.1.PDF


 .../bindings/display/multi-inno,mi0283qt.txt       | 27 ++++++++++++++++++++++
 1 file changed, 27 insertions(+)
 create mode 100644 Documentation/devicetree/bindings/display/multi-inno,mi0283qt.txt

diff --git a/Documentation/devicetree/bindings/display/multi-inno,mi0283qt.txt b/Documentation/devicetree/bindings/display/multi-inno,mi0283qt.txt
new file mode 100644
index 0000000..eed48c3
--- /dev/null
+++ b/Documentation/devicetree/bindings/display/multi-inno,mi0283qt.txt
@@ -0,0 +1,27 @@
+Multi-Inno MI0283QT display panel
+
+Required properties:
+- compatible:	"multi-inno,mi0283qt".
+
+The node for this driver must be a child node of a SPI controller, hence
+all mandatory properties described in ../spi/spi-bus.txt must be specified.
+
+Optional properties:
+- dc-gpios:	D/C pin. The presence/absence of this GPIO determines
+		the panel interface mode (IM[3:0] pins):
+		- present: IM=x110 4-wire 8-bit data serial interface
+		- absent:  IM=x101 3-wire 9-bit data serial interface
+- reset-gpios:	Reset pin
+- power-supply:	A regulator node for the supply voltage.
+- backlight:	phandle of the backlight device attached to the panel
+- rotation:	panel rotation in degrees counter clockwise (0,90,180,270)
+
+Example:
+	mi0283qt@0{
+		compatible = "multi-inno,mi0283qt";
+		reg = <0>;
+		spi-max-frequency = <32000000>;
+		rotation = <90>;
+		dc-gpios = <&gpio 25 0>;
+		backlight = <&backlight>;
+	};
--
2.10.2

_______________________________________________
dri-devel mailing list
dri-devel@lists.freedesktop.org
https://lists.freedesktop.org/mailman/listinfo/dri-devel

Re: [PATCH 8/9] dt-bindings: Add Multi-Inno MI0283QT binding

[Rob Herring]

On Sun, Jan 22, 2017 at 07:11:16PM +0100, Noralf Trønnes wrote:
> Add device-tree binding documentation for the MI0283QT display panel.
> 
> Signed-off-by: Noralf Trønnes <noralf@tronnes.org>
> ---
> 
> Datasheet: https://cdn-shop.adafruit.com/datasheets/MI0283QT-11+V1.1.PDF
> 
> 
>  .../bindings/display/multi-inno,mi0283qt.txt       | 27 ++++++++++++++++++++++
>  1 file changed, 27 insertions(+)
>  create mode 100644 Documentation/devicetree/bindings/display/multi-inno,mi0283qt.txt
> 
> diff --git a/Documentation/devicetree/bindings/display/multi-inno,mi0283qt.txt b/Documentation/devicetree/bindings/display/multi-inno,mi0283qt.txt
> new file mode 100644
> index 0000000..eed48c3
> --- /dev/null
> +++ b/Documentation/devicetree/bindings/display/multi-inno,mi0283qt.txt
> @@ -0,0 +1,27 @@
> +Multi-Inno MI0283QT display panel
> +
> +Required properties:
> +- compatible:	"multi-inno,mi0283qt".
> +
> +The node for this driver must be a child node of a SPI controller, hence
> +all mandatory properties described in ../spi/spi-bus.txt must be specified.
> +
> +Optional properties:
> +- dc-gpios:	D/C pin. The presence/absence of this GPIO determines
> +		the panel interface mode (IM[3:0] pins):
> +		- present: IM=x110 4-wire 8-bit data serial interface
> +		- absent:  IM=x101 3-wire 9-bit data serial interface
> +- reset-gpios:	Reset pin
> +- power-supply:	A regulator node for the supply voltage.
> +- backlight:	phandle of the backlight device attached to the panel
> +- rotation:	panel rotation in degrees counter clockwise (0,90,180,270)

This isn't a standard property, but probably should be. Please document 
in a common spot.

> +
> +Example:
> +	mi0283qt@0{
> +		compatible = "multi-inno,mi0283qt";
> +		reg = <0>;
> +		spi-max-frequency = <32000000>;
> +		rotation = <90>;
> +		dc-gpios = <&gpio 25 0>;
> +		backlight = <&backlight>;
> +	};
> --
> 2.10.2
> 
> --
> To unsubscribe from this list: send the line "unsubscribe devicetree" in
> the body of a message to majordomo@vger.kernel.org
> More majordomo info at  http://vger.kernel.org/majordomo-info.html
_______________________________________________
dri-devel mailing list
dri-devel@lists.freedesktop.org
https://lists.freedesktop.org/mailman/listinfo/dri-devel

[PATCH 9/9] drm/tinydrm: Add support for Multi-Inno MI0283QT display

[Noralf Trønnes]

Add driver to support the Multi-Inno MI0283QT display panel.
It has an ILI9341 MIPI DBI compatible display controller.

Signed-off-by: Noralf Trønnes <noralf@tronnes.org>
---
 MAINTAINERS                        |   6 +
 drivers/gpu/drm/tinydrm/Kconfig    |   8 ++
 drivers/gpu/drm/tinydrm/Makefile   |   3 +
 drivers/gpu/drm/tinydrm/mi0283qt.c | 279 +++++++++++++++++++++++++++++++++++++
 include/drm/tinydrm/ili9341.h      |  54 +++++++
 5 files changed, 350 insertions(+)
 create mode 100644 drivers/gpu/drm/tinydrm/mi0283qt.c
 create mode 100644 include/drm/tinydrm/ili9341.h

diff --git a/MAINTAINERS b/MAINTAINERS
index 817e0fe..8301800 100644
--- a/MAINTAINERS
+++ b/MAINTAINERS
@@ -4271,6 +4271,12 @@ S:	Supported
 F:	drivers/gpu/drm/mediatek/
 F:	Documentation/devicetree/bindings/display/mediatek/
 
+DRM DRIVER FOR MI0283QT
+M:	Noralf Trønnes <noralf@tronnes.org>
+S:	Maintained
+F:	drivers/gpu/drm/tinydrm/mi0283qt.c
+F:	Documentation/devicetree/bindings/display/multi-inno,mi0283qt.txt
+
 DRM DRIVER FOR MSM ADRENO GPU
 M:	Rob Clark <robdclark@gmail.com>
 L:	linux-arm-msm@vger.kernel.org
diff --git a/drivers/gpu/drm/tinydrm/Kconfig b/drivers/gpu/drm/tinydrm/Kconfig
index 128d2f3..d3161fd 100644
--- a/drivers/gpu/drm/tinydrm/Kconfig
+++ b/drivers/gpu/drm/tinydrm/Kconfig
@@ -9,3 +9,11 @@ menuconfig DRM_TINYDRM
 
 config TINYDRM_MIPI_DBI
 	tristate
+
+config TINYDRM_MI0283QT
+	tristate "DRM support for MI0283QT"
+	depends on DRM_TINYDRM && SPI
+	select TINYDRM_MIPI_DBI
+	help
+	  DRM driver for the Multi-Inno MI0283QT display panel
+	  If M is selected the module will be called mi0283qt.
diff --git a/drivers/gpu/drm/tinydrm/Makefile b/drivers/gpu/drm/tinydrm/Makefile
index fe5d4c6..7a3604c 100644
--- a/drivers/gpu/drm/tinydrm/Makefile
+++ b/drivers/gpu/drm/tinydrm/Makefile
@@ -2,3 +2,6 @@ obj-$(CONFIG_DRM_TINYDRM)		+= core/
 
 # Controllers
 obj-$(CONFIG_TINYDRM_MIPI_DBI)		+= mipi-dbi.o
+
+# Displays
+obj-$(CONFIG_TINYDRM_MI0283QT)		+= mi0283qt.o
diff --git a/drivers/gpu/drm/tinydrm/mi0283qt.c b/drivers/gpu/drm/tinydrm/mi0283qt.c
new file mode 100644
index 0000000..b29fe86
--- /dev/null
+++ b/drivers/gpu/drm/tinydrm/mi0283qt.c
@@ -0,0 +1,279 @@
+/*
+ * DRM driver for Multi-Inno MI0283QT panels
+ *
+ * Copyright 2016 Noralf Trønnes
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ */
+
+#include <drm/tinydrm/ili9341.h>
+#include <drm/tinydrm/mipi-dbi.h>
+#include <drm/tinydrm/tinydrm-helpers.h>
+#include <linux/delay.h>
+#include <linux/gpio/consumer.h>
+#include <linux/module.h>
+#include <linux/property.h>
+#include <linux/regulator/consumer.h>
+#include <linux/spi/spi.h>
+#include <video/mipi_display.h>
+
+static int mi0283qt_init(struct mipi_dbi *mipi)
+{
+	struct tinydrm_device *tdev = &mipi->tinydrm;
+	struct device *dev = tdev->drm->dev;
+	u8 addr_mode;
+	int ret;
+
+	DRM_DEBUG_KMS("\n");
+
+	ret = regulator_enable(mipi->regulator);
+	if (ret) {
+		dev_err(dev, "Failed to enable regulator %d\n", ret);
+		return ret;
+	}
+
+	/* Avoid flicker by skipping setup if the bootloader has done it */
+	if (mipi_dbi_display_is_on(mipi))
+		return 0;
+
+	mipi_dbi_hw_reset(mipi);
+	ret = mipi_dbi_command(mipi, MIPI_DCS_SOFT_RESET);
+	if (ret) {
+		dev_err(dev, "Error sending command %d\n", ret);
+		regulator_disable(mipi->regulator);
+		return ret;
+	}
+
+	msleep(20);
+
+	mipi_dbi_command(mipi, MIPI_DCS_SET_DISPLAY_OFF);
+
+	mipi_dbi_command(mipi, ILI9341_PWCTRLB, 0x00, 0x83, 0x30);
+	mipi_dbi_command(mipi, ILI9341_PWRSEQ, 0x64, 0x03, 0x12, 0x81);
+	mipi_dbi_command(mipi, ILI9341_DTCTRLA, 0x85, 0x01, 0x79);
+	mipi_dbi_command(mipi, ILI9341_PWCTRLA, 0x39, 0x2c, 0x00, 0x34, 0x02);
+	mipi_dbi_command(mipi, ILI9341_PUMPCTRL, 0x20);
+	mipi_dbi_command(mipi, ILI9341_DTCTRLB, 0x00, 0x00);
+
+	/* Power Control */
+	mipi_dbi_command(mipi, ILI9341_PWCTRL1, 0x26);
+	mipi_dbi_command(mipi, ILI9341_PWCTRL2, 0x11);
+	/* VCOM */
+	mipi_dbi_command(mipi, ILI9341_VMCTRL1, 0x35, 0x3e);
+	mipi_dbi_command(mipi, ILI9341_VMCTRL2, 0xbe);
+
+	/* Memory Access Control */
+	mipi_dbi_command(mipi, MIPI_DCS_SET_PIXEL_FORMAT, 0x55);
+
+	switch (mipi->rotation) {
+	default:
+		addr_mode = ILI9341_MADCTL_MV | ILI9341_MADCTL_MY |
+			    ILI9341_MADCTL_MX;
+		break;
+	case 90:
+		addr_mode = ILI9341_MADCTL_MY;
+		break;
+	case 180:
+		addr_mode = ILI9341_MADCTL_MV;
+		break;
+	case 270:
+		addr_mode = ILI9341_MADCTL_MX;
+		break;
+	}
+	addr_mode |= ILI9341_MADCTL_BGR;
+	mipi_dbi_command(mipi, MIPI_DCS_SET_ADDRESS_MODE, addr_mode);
+
+	/* Frame Rate */
+	mipi_dbi_command(mipi, ILI9341_FRMCTR1, 0x00, 0x1b);
+
+	/* Gamma */
+	mipi_dbi_command(mipi, ILI9341_EN3GAM, 0x08);
+	mipi_dbi_command(mipi, MIPI_DCS_SET_GAMMA_CURVE, 0x01);
+	mipi_dbi_command(mipi, ILI9341_PGAMCTRL,
+		       0x1f, 0x1a, 0x18, 0x0a, 0x0f, 0x06, 0x45, 0x87,
+		       0x32, 0x0a, 0x07, 0x02, 0x07, 0x05, 0x00);
+	mipi_dbi_command(mipi, ILI9341_NGAMCTRL,
+		       0x00, 0x25, 0x27, 0x05, 0x10, 0x09, 0x3a, 0x78,
+		       0x4d, 0x05, 0x18, 0x0d, 0x38, 0x3a, 0x1f);
+
+	/* DDRAM */
+	mipi_dbi_command(mipi, ILI9341_ETMOD, 0x07);
+
+	/* Display */
+	mipi_dbi_command(mipi, ILI9341_DISCTRL, 0x0a, 0x82, 0x27, 0x00);
+	mipi_dbi_command(mipi, MIPI_DCS_EXIT_SLEEP_MODE);
+	msleep(100);
+
+	mipi_dbi_command(mipi, MIPI_DCS_SET_DISPLAY_ON);
+	msleep(100);
+
+	return 0;
+}
+
+static void mi0283qt_fini(void *data)
+{
+	struct mipi_dbi *mipi = data;
+
+	DRM_DEBUG_KMS("\n");
+	regulator_disable(mipi->regulator);
+}
+
+static const struct drm_simple_display_pipe_funcs mi0283qt_pipe_funcs = {
+	.enable = mipi_dbi_pipe_enable,
+	.disable = mipi_dbi_pipe_disable,
+	.update = tinydrm_display_pipe_update,
+	.prepare_fb = tinydrm_display_pipe_prepare_fb,
+};
+
+static const struct drm_display_mode mi0283qt_mode = {
+	TINYDRM_MODE(320, 240, 58, 43),
+};
+
+static struct drm_driver mi0283qt_driver = {
+	.driver_features	= DRIVER_GEM | DRIVER_MODESET | DRIVER_PRIME |
+				  DRIVER_ATOMIC,
+	TINYDRM_GEM_DRIVER_OPS,
+	.lastclose		= tinydrm_lastclose,
+	.debugfs_init		= mipi_dbi_debugfs_init,
+	.name			= "mi0283qt",
+	.desc			= "Multi-Inno MI0283QT",
+	.date			= "20160614",
+	.major			= 1,
+	.minor			= 0,
+};
+
+static const struct of_device_id mi0283qt_of_match[] = {
+	{ .compatible = "multi-inno,mi0283qt" },
+	{},
+};
+MODULE_DEVICE_TABLE(of, mi0283qt_of_match);
+
+static const struct spi_device_id mi0283qt_id[] = {
+	{ "mi0283qt", 0 },
+	{ },
+};
+MODULE_DEVICE_TABLE(spi, mi0283qt_id);
+
+static int mi0283qt_probe(struct spi_device *spi)
+{
+	struct device *dev = &spi->dev;
+	struct tinydrm_device *tdev;
+	struct mipi_dbi *mipi;
+	struct gpio_desc *dc;
+	u32 rotation = 0;
+	int ret;
+
+	mipi = devm_kzalloc(dev, sizeof(*mipi), GFP_KERNEL);
+	if (!mipi)
+		return -ENOMEM;
+
+	mipi->reset = devm_gpiod_get_optional(dev, "reset", GPIOD_OUT_HIGH);
+	if (IS_ERR(mipi->reset)) {
+		dev_err(dev, "Failed to get gpio 'reset'\n");
+		return PTR_ERR(mipi->reset);
+	}
+
+	dc = devm_gpiod_get_optional(dev, "dc", GPIOD_OUT_LOW);
+	if (IS_ERR(dc)) {
+		dev_err(dev, "Failed to get gpio 'dc'\n");
+		return PTR_ERR(dc);
+	}
+
+	mipi->regulator = devm_regulator_get(dev, "power");
+	if (IS_ERR(mipi->regulator))
+		return PTR_ERR(mipi->regulator);
+
+	mipi->backlight = tinydrm_of_find_backlight(dev);
+	if (IS_ERR(mipi->backlight))
+		return PTR_ERR(mipi->backlight);
+
+	device_property_read_u32(dev, "rotation", &rotation);
+
+	ret = mipi_dbi_spi_init(spi, mipi, dc, &mi0283qt_pipe_funcs,
+				&mi0283qt_driver, &mi0283qt_mode, rotation);
+	if (ret)
+		return ret;
+
+	ret = mi0283qt_init(mipi);
+	if (ret)
+		return ret;
+
+	/* use devres to fini after drm unregister (drv->remove is before) */
+	ret = devm_add_action(dev, mi0283qt_fini, mipi);
+	if (ret) {
+		mi0283qt_fini(mipi);
+		return ret;
+	}
+
+	tdev = &mipi->tinydrm;
+
+	ret = devm_tinydrm_register(tdev);
+	if (ret)
+		return ret;
+
+	spi_set_drvdata(spi, mipi);
+
+	DRM_DEBUG_DRIVER("Initialized %s:%s @%uMHz on minor %d\n",
+			 tdev->drm->driver->name, dev_name(dev),
+			 spi->max_speed_hz / 1000000,
+			 tdev->drm->primary->index);
+
+	return 0;
+}
+
+static void mi0283qt_shutdown(struct spi_device *spi)
+{
+	struct mipi_dbi *mipi = spi_get_drvdata(spi);
+
+	tinydrm_shutdown(&mipi->tinydrm);
+}
+
+static int __maybe_unused mi0283qt_pm_suspend(struct device *dev)
+{
+	struct mipi_dbi *mipi = dev_get_drvdata(dev);
+	int ret;
+
+	ret = tinydrm_suspend(&mipi->tinydrm);
+	if (ret)
+		return ret;
+
+	mi0283qt_fini(mipi);
+
+	return 0;
+}
+
+static int __maybe_unused mi0283qt_pm_resume(struct device *dev)
+{
+	struct mipi_dbi *mipi = dev_get_drvdata(dev);
+	int ret;
+
+	ret = mi0283qt_init(mipi);
+	if (ret)
+		return ret;
+
+	return tinydrm_resume(&mipi->tinydrm);
+}
+
+static const struct dev_pm_ops mi0283qt_pm_ops = {
+	SET_SYSTEM_SLEEP_PM_OPS(mi0283qt_pm_suspend, mi0283qt_pm_resume)
+};
+
+static struct spi_driver mi0283qt_spi_driver = {
+	.driver = {
+		.name = "mi0283qt",
+		.owner = THIS_MODULE,
+		.of_match_table = mi0283qt_of_match,
+		.pm = &mi0283qt_pm_ops,
+	},
+	.id_table = mi0283qt_id,
+	.probe = mi0283qt_probe,
+	.shutdown = mi0283qt_shutdown,
+};
+module_spi_driver(mi0283qt_spi_driver);
+
+MODULE_DESCRIPTION("Multi-Inno MI0283QT DRM driver");
+MODULE_AUTHOR("Noralf Trønnes");
+MODULE_LICENSE("GPL");
diff --git a/include/drm/tinydrm/ili9341.h b/include/drm/tinydrm/ili9341.h
new file mode 100644
index 0000000..807a09f
--- /dev/null
+++ b/include/drm/tinydrm/ili9341.h
@@ -0,0 +1,54 @@
+/*
+ * ILI9341 LCD controller
+ *
+ * Copyright 2016 Noralf Trønnes
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ */
+
+#ifndef __LINUX_ILI9341_H
+#define __LINUX_ILI9341_H
+
+#define ILI9341_FRMCTR1    0xb1
+#define ILI9341_FRMCTR2    0xb2
+#define ILI9341_FRMCTR3    0xb3
+#define ILI9341_INVTR      0xb4
+#define ILI9341_PRCTR      0xb5
+#define ILI9341_DISCTRL    0xb6
+#define ILI9341_ETMOD      0xb7
+
+#define ILI9341_PWCTRL1    0xc0
+#define ILI9341_PWCTRL2    0xc1
+#define ILI9341_VMCTRL1    0xc5
+#define ILI9341_VMCTRL2    0xc7
+#define ILI9341_PWCTRLA    0xcb
+#define ILI9341_PWCTRLB    0xcf
+
+#define ILI9341_RDID1      0xda
+#define ILI9341_RDID2      0xdb
+#define ILI9341_RDID3      0xdc
+#define ILI9341_RDID4      0xd3
+
+#define ILI9341_PGAMCTRL   0xe0
+#define ILI9341_NGAMCTRL   0xe1
+#define ILI9341_DGAMCTRL1  0xe2
+#define ILI9341_DGAMCTRL2  0xe3
+#define ILI9341_DTCTRLA    0xe8
+#define ILI9341_DTCTRLB    0xea
+#define ILI9341_PWRSEQ     0xed
+
+#define ILI9341_EN3GAM     0xf2
+#define ILI9341_IFCTRL     0xf6
+#define ILI9341_PUMPCTRL   0xf7
+
+#define ILI9341_MADCTL_MH  BIT(2)
+#define ILI9341_MADCTL_BGR BIT(3)
+#define ILI9341_MADCTL_ML  BIT(4)
+#define ILI9341_MADCTL_MV  BIT(5)
+#define ILI9341_MADCTL_MX  BIT(6)
+#define ILI9341_MADCTL_MY  BIT(7)
+
+#endif /* __LINUX_ILI9341_H */
-- 
2.10.2

_______________________________________________
dri-devel mailing list
dri-devel@lists.freedesktop.org
https://lists.freedesktop.org/mailman/listinfo/dri-devel