It is difficult for a user to know which of the i2c adapters is for which drm connector. This series addresses this problem. The idea is to have a symbolic link in connector's sysfs directory, e.g.: ls -l /sys/class/drm/card0-HDMI-A-1/ddc lrwxrwxrwx 1 root root 0 Jun 24 10:42 /sys/class/drm/card0-HDMI-A-1/ddc \ -> ../../../../soc/13880000.i2c/i2c-2 The user then knows that their card0-HDMI-A-1 uses i2c-2 and can e.g. run ddcutil: ddcutil -b 2 getvcp 0x10 VCP code 0x10 (Brightness): current value = 90, max value = 100 The first patch in the series adds struct i2c_adapter pointer to struct drm_connector. If the field is used by a particular driver, then an appropriate symbolic link is created by the generic code, which is also added by this patch. Patch 2 adds a new variant of drm_connector_init(), see the changelog below. Patches 3..24 are examples of how to convert a driver to this new scheme. v1..v2: - used fixed name "ddc" for the symbolic link in order to make it easy for userspace to find the i2c adapter v2..v3: - converted as many drivers as possible. v3..v4: - added Reviewed-by for patch 01/23 - moved "ddc" field assignment to before drm_connector_init() is called in msm, vc4, sti, mgag200, ast, amdgpu, radeon - simplified the code in amdgpu and radeon at the expense of some lines exceeding 80 characters as per Alex Deucher's suggestion - added i915 v4..v5: - changed "include <linux/i2c.h>" to "struct i2c_adapter;" in drm_connector.h, consequently, added "include <linux/i2c.h>" in drm_sysfs.c. - added "drm_connector_init_with_ddc()" variant to ensure that the ddc field of drm_connector is preserved accross its invocation - accordingly changed invocations of drm_connector_init() in the touched drivers to use the new variant v5..v6: - improved subject line of patch 1 - added kernel-doc for drm_connector_init_with_ddc() - improved kernel-doc for the ddc field of struct drm_connector - added Reviewed-by in patches 17 and 18 - added Acked-by in patch 2 - made the ownership of ddc i2c_adapter explicit in all patches, this made the affected patches much simpler @Benjamin @Shawn There were your Acked-by or Reviewed-by for some patches in v4, but now that the patches use the newly added function I'm not sure I can still include those tags without you actually confirming. Can I? Or can you please re-review? TODO: nouveau, gma500, omapdrm, panel-simple - if applicable. Other drivers are either already converted or don't mention neither "ddc" nor "i2c_adapter". Andrzej Pietrasiewicz (24): drm: Add ddc link in sysfs created by drm_connector drm: Add drm_connector_init() variant with ddc drm/exynos: Provide ddc symlink in connector's sysfs drm: rockchip: Provide ddc symlink in rk3066_hdmi sysfs directory drm: rockchip: Provide ddc symlink in inno_hdmi sysfs directory drm/msm/hdmi: Provide ddc symlink in hdmi connector sysfs directory drm/sun4i: hdmi: Provide ddc symlink in sun4i hdmi connector sysfs directory drm/mediatek: Provide ddc symlink in hdmi connector sysfs directory drm/tegra: Provide ddc symlink in output connector sysfs directory drm/imx: imx-ldb: Provide ddc symlink in connector's sysfs drm/imx: imx-tve: Provide ddc symlink in connector's sysfs drm/vc4: Provide ddc symlink in connector sysfs directory drm: zte: Provide ddc symlink in hdmi connector sysfs directory drm: zte: Provide ddc symlink in vga connector sysfs directory drm/tilcdc: Provide ddc symlink in connector sysfs directory drm: sti: Provide ddc symlink in hdmi connector sysfs directory drm/mgag200: Provide ddc symlink in connector sysfs directory drm/ast: Provide ddc symlink in connector sysfs directory drm/bridge: dumb-vga-dac: Provide ddc symlink in connector sysfs directory drm/bridge: dw-hdmi: Provide ddc symlink in connector sysfs directory drm/bridge: ti-tfp410: Provide ddc symlink in connector sysfs directory drm/amdgpu: Provide ddc symlink in connector sysfs directory drm/radeon: Provide ddc symlink in connector sysfs directory drm/i915: Provide ddc symlink in hdmi connector sysfs directory .../gpu/drm/amd/amdgpu/amdgpu_connectors.c | 96 ++++++++---- drivers/gpu/drm/ast/ast_mode.c | 13 +- drivers/gpu/drm/bridge/dumb-vga-dac.c | 6 +- drivers/gpu/drm/bridge/synopsys/dw-hdmi.c | 6 +- drivers/gpu/drm/bridge/ti-tfp410.c | 6 +- drivers/gpu/drm/drm_connector.c | 35 +++++ drivers/gpu/drm/drm_sysfs.c | 8 + drivers/gpu/drm/exynos/exynos_hdmi.c | 6 +- drivers/gpu/drm/i915/display/intel_hdmi.c | 12 +- drivers/gpu/drm/imx/imx-ldb.c | 7 +- drivers/gpu/drm/imx/imx-tve.c | 6 +- drivers/gpu/drm/mediatek/mtk_hdmi.c | 7 +- drivers/gpu/drm/mgag200/mgag200_mode.c | 13 +- drivers/gpu/drm/msm/hdmi/hdmi_connector.c | 6 +- drivers/gpu/drm/radeon/radeon_connectors.c | 142 +++++++++++++----- drivers/gpu/drm/rockchip/inno_hdmi.c | 6 +- drivers/gpu/drm/rockchip/rk3066_hdmi.c | 7 +- drivers/gpu/drm/sti/sti_hdmi.c | 6 +- drivers/gpu/drm/sun4i/sun4i_hdmi_enc.c | 7 +- drivers/gpu/drm/tegra/hdmi.c | 7 +- drivers/gpu/drm/tegra/sor.c | 7 +- drivers/gpu/drm/tilcdc/tilcdc_tfp410.c | 6 +- drivers/gpu/drm/vc4/vc4_hdmi.c | 12 +- drivers/gpu/drm/zte/zx_hdmi.c | 6 +- drivers/gpu/drm/zte/zx_vga.c | 6 +- include/drm/drm_connector.h | 18 +++ 26 files changed, 336 insertions(+), 121 deletions(-) -- 2.17.1 _______________________________________________ dri-devel mailing list dri-devel@xxxxxxxxxxxxxxxxxxxxx https://lists.freedesktop.org/mailman/listinfo/dri-devel