Messages in this thread | | | Date | Wed, 16 Mar 2022 20:12:41 +0100 | Subject | Re: [PATCH] drm/panel: add CONFIG_DRM_KMS_HELPER dependencies | From | Thomas Zimmermann <> |
| |
Hi
Am 16.03.22 um 19:36 schrieb Arnd Bergmann: > From: Arnd Bergmann <arnd@arndb.de> > > The driver fails to build when the KMS helpers are disabled: > > ld.lld: error: undefined symbol: drm_gem_fb_get_obj >>>> referenced by drm_mipi_dbi.c >>>> gpu/drm/drm_mipi_dbi.o:(mipi_dbi_buf_copy) in archive drivers/built-in.a >>>> referenced by drm_mipi_dbi.c >>>> gpu/drm/drm_mipi_dbi.o:(mipi_dbi_fb_dirty) in archive drivers/built-in.a > > ld.lld: error: undefined symbol: drm_gem_fb_begin_cpu_access >>>> referenced by drm_mipi_dbi.c >>>> gpu/drm/drm_mipi_dbi.o:(mipi_dbi_buf_copy) in archive drivers/built-in.a > > ld.lld: error: undefined symbol: drm_fb_swab >>>> referenced by drm_mipi_dbi.c >>>> gpu/drm/drm_mipi_dbi.o:(mipi_dbi_buf_copy) in archive drivers/built-in.a > > ld.lld: error: undefined symbol: drm_fb_xrgb8888_to_rgb565 >>>> referenced by drm_mipi_dbi.c >>>> gpu/drm/drm_mipi_dbi.o:(mipi_dbi_buf_copy) in archive drivers/built-in.a > > ld.lld: error: undefined symbol: drm_fb_memcpy >>>> referenced by drm_mipi_dbi.c >>>> gpu/drm/drm_mipi_dbi.o:(mipi_dbi_buf_copy) in archive drivers/built-in.a > > This is fairly hard to hit in randconfig drivers, but it eventually > did trigger for me in a configuration where all other DRM drivers > are loadable modules, but DRM_PANEL_WIDECHIPS_WS2401 was built-in. > > Adding a dependency in all drivers that select DRM_MIPI_DBI avoids > the problem for now, adding the dependency in DRM_MIPI_DBI as well > should help make it easier to figure out why it breaks if someone > forgets the dependency the next time. > > Signed-off-by: Arnd Bergmann <arnd@arndb.de> > --- > drivers/gpu/drm/Kconfig | 2 +- > drivers/gpu/drm/panel/Kconfig | 4 ++++ > 2 files changed, 5 insertions(+), 1 deletion(-) > > I see this warning on 5.17-rc8, but did not test it on linux-next, > which may already have a fix. > > > diff --git a/drivers/gpu/drm/Kconfig b/drivers/gpu/drm/Kconfig > index b1f22e457fd0..d5ec0b77c010 100644 > --- a/drivers/gpu/drm/Kconfig > +++ b/drivers/gpu/drm/Kconfig > @@ -30,7 +30,7 @@ menuconfig DRM > > config DRM_MIPI_DBI > tristate > - depends on DRM > + depends on DRM_KMS_HELPER
This symbol cannot be selected by users, so it's maybe not a good idea to depend on it. In fact, I've had to remove such a statement because it created a cyclic dependency. [1]
Making the drivers depend on KMS helpers is the right thing though. If there's a better solution, please let me know.
Best regards Thomas
> > config DRM_MIPI_DSI > bool > diff --git a/drivers/gpu/drm/panel/Kconfig b/drivers/gpu/drm/panel/Kconfig > index 0aec5a10b064..96887d0efb9f 100644 > --- a/drivers/gpu/drm/panel/Kconfig > +++ b/drivers/gpu/drm/panel/Kconfig > @@ -425,6 +425,7 @@ config DRM_PANEL_SAMSUNG_DB7430 > tristate "Samsung DB7430-based DPI panels" > depends on OF && SPI && GPIOLIB > depends on BACKLIGHT_CLASS_DEVICE > + depends on DRM_KMS_HELPER > select DRM_MIPI_DBI > help > Say Y here if you want to enable support for the Samsung > @@ -440,6 +441,7 @@ config DRM_PANEL_SAMSUNG_S6D16D0 > config DRM_PANEL_SAMSUNG_S6D27A1 > tristate "Samsung S6D27A1 DPI panel driver" > depends on OF && SPI && GPIOLIB > + depends on DRM_KMS_HELPER > select DRM_MIPI_DBI > help > Say Y here if you want to enable support for the Samsung > @@ -476,6 +478,7 @@ config DRM_PANEL_SAMSUNG_S6E63M0_SPI > depends on SPI > depends on DRM_PANEL_SAMSUNG_S6E63M0 > default DRM_PANEL_SAMSUNG_S6E63M0 > + depends on DRM_KMS_HELPER > select DRM_MIPI_DBI > help > Say Y here if you want to be able to access the Samsung > @@ -677,6 +680,7 @@ config DRM_PANEL_WIDECHIPS_WS2401 > tristate "Widechips WS2401 DPI panel driver" > depends on SPI && GPIOLIB > depends on BACKLIGHT_CLASS_DEVICE > + depends on DRM_KMS_HELPER > select DRM_MIPI_DBI > help > Say Y here if you want to enable support for the Widechips WS2401 DPI
-- Thomas Zimmermann Graphics Driver Developer SUSE Software Solutions Germany GmbH Maxfeldstr. 5, 90409 Nürnberg, Germany (HRB 36809, AG Nürnberg) Geschäftsführer: Ivo Totev [unhandled content-type:application/pgp-signature] | |