| Message ID | 20230901234015.566018-1-dianders@chromium.org |
|---|---|
| Headers | show |
| Series | drm: drm-misc drivers call drm_atomic_helper_shutdown() at the right times | expand |
Hi, On Fri, Sep 1, 2023 at 4:40 PM Douglas Anderson <dianders@chromium.org> wrote: > > > NOTE: in order to avoid email sending limits on the cover letter, I've > split this patch series in two. Patches that target drm-misc and ones > that don't. The cover letter of the two is identical other than this note. > > This patch series came about after a _long_ discussion between me and > Maxime Ripard in response to a different patch I sent out [1]. As part > of that discussion, we realized that it would be good if DRM drivers > consistently called drm_atomic_helper_shutdown() properly at shutdown > and driver remove time as it's documented that they should do. The > eventual goal of this would be to enable removing some hacky code from > panel drivers where they had to hook into shutdown themselves because > the DRM driver wasn't calling them. > > It turns out that quite a lot of drivers seemed to be missing > drm_atomic_helper_shutdown() in one or both places that it was > supposed to be. This patch series attempts to fix all the drivers that > I was able to identify. > > NOTE: fixing this wasn't exactly cookie cutter. Each driver has its > own unique way of setting itself up and tearing itself down. Some > drivers also use the component model, which adds extra fun. I've made > my best guess at solving this and I've run a bunch of compile tests > (specifically, allmodconfig for amd64, arm64, and powerpc). That being > said, these code changes are not totally trivial and I've done zero > real testing on them. Making these patches was also a little mind > numbing and I'm certain my eyes glazed over at several points when > writing them. What I'm trying to say is to please double-check that I > didn't do anything too silly, like cast your driver's drvdata to the > wrong type. Even better, test these patches! > > I've organized this series like this: > 1. One patch for all simple cases of just needing a call at shutdown > time for drivers that go through drm-misc. > 2. A separate patch for "drm/vc4", even though it goes through > drm-misc, since I wanted to leave an extra note for that one. > 3. Patches for drivers that just needed a call at shutdown time for > drivers that _don't_ go through drm-misc. > 4. Patches for the few drivers that had the call at shutdown time but > lacked it at remove time. > 5. One patch for all simple cases of needing a call at shutdown and > remove (or unbind) time for drivers that go through drm-misc. > 6. A separate patch for "drm/hisilicon/kirin", even though it goes > through drm-misc, since I wanted to leave an extra note for that > one. > 7. Patches for drivers that needed a call at shutdown and remove (or > unbind) time for drivers that _don't_ go through drm-misc. > > I've labeled this patch series as RFT (request for testing) to help > call attention to the fact that I didn't personally test any of these > patches. > > If you're a maintainer of one of these drivers and you think that the > patch for your driver looks fabulous, you've tested it, and you'd like > to land it right away then please do. For non-drm-misc drivers there > are no dependencies here. Some of the drm-misc drivers depend on the > first patch, AKA ("drm/atomic-helper: drm_atomic_helper_shutdown(NULL) > should be a noop"). I've tried to call this out but it also should be > obvious once you know to look for it. > > I'd like to call out a few drivers that I _didn't_ fix in this series > and why. If any of these drivers should be fixed then please yell. > - DRM driers backed by usb_driver (like gud, gm12u320, udl): I didn't > add the call to drm_atomic_helper_shutdown() at shutdown time > because there's no ".shutdown" callback for them USB drivers. Given > that USB is hotpluggable, I'm assuming that they are robust against > this and the special shutdown callback isn't needed. > - ofdrm and simpledrm: These didn't have drm_atomic_helper_shutdown() > in either shutdown or remove, but I didn't add it. I think that's OK > since they're sorta special and not really directly controlling > hardware power sequencing. > - virtio, vkms, vmwgfx, xen: I believe these are all virtual (thus > they wouldn't directly drive a panel) and adding the shutdown > didn't look straightforward, so I skipped them. > > I've let each patch in the series get CCed straight from > get_maintainer. That means not everyone will have received every patch > but everyone should be on the cover letter. I know some people dislike > this but when touching this many drivers there's not much > choice. dri-devel and lkml have been CCed and lore/lei exist, so > hopefully that's enough for folks. I'm happy to add people to the > whole series for future posts. > > [1] https://lore.kernel.org/lkml/20230804140605.RFC.4.I930069a32baab6faf46d6b234f89613b5cec0f14@changeid > > > Douglas Anderson (6): > drm/atomic-helper: drm_atomic_helper_shutdown(NULL) should be a noop > drm: Call drm_atomic_helper_shutdown() at shutdown time for misc > drivers > drm/vc4: Call drm_atomic_helper_shutdown() at shutdown time > drm/ssd130x: Call drm_atomic_helper_shutdown() at remove time > drm: Call drm_atomic_helper_shutdown() at shutdown/remove time for > misc drivers > drm/hisilicon/kirin: Call drm_atomic_helper_shutdown() at > shutdown/unbind time > > .../gpu/drm/arm/display/komeda/komeda_drv.c | 9 +++++ > .../gpu/drm/arm/display/komeda/komeda_kms.c | 7 ++++ > .../gpu/drm/arm/display/komeda/komeda_kms.h | 1 + > drivers/gpu/drm/arm/hdlcd_drv.c | 6 ++++ > drivers/gpu/drm/arm/malidp_drv.c | 6 ++++ > drivers/gpu/drm/aspeed/aspeed_gfx_drv.c | 7 ++++ > drivers/gpu/drm/ast/ast_drv.c | 6 ++++ > drivers/gpu/drm/atmel-hlcdc/atmel_hlcdc_dc.c | 6 ++++ > drivers/gpu/drm/drm_atomic_helper.c | 3 ++ > drivers/gpu/drm/fsl-dcu/fsl_dcu_drm_drv.c | 8 +++++ > .../gpu/drm/hisilicon/hibmc/hibmc_drm_drv.c | 6 ++++ > .../gpu/drm/hisilicon/kirin/kirin_drm_drv.c | 9 +++++ > drivers/gpu/drm/hyperv/hyperv_drm_drv.c | 6 ++++ > drivers/gpu/drm/logicvc/logicvc_drm.c | 9 +++++ > drivers/gpu/drm/loongson/lsdc_drv.c | 6 ++++ > drivers/gpu/drm/mcde/mcde_drv.c | 9 +++++ > drivers/gpu/drm/mgag200/mgag200_drv.c | 8 +++++ > drivers/gpu/drm/omapdrm/omap_drv.c | 8 +++++ > drivers/gpu/drm/pl111/pl111_drv.c | 7 ++++ > drivers/gpu/drm/qxl/qxl_drv.c | 7 ++++ > drivers/gpu/drm/solomon/ssd130x.c | 1 + > drivers/gpu/drm/sti/sti_drv.c | 7 ++++ > drivers/gpu/drm/stm/drv.c | 7 ++++ > drivers/gpu/drm/sun4i/sun4i_drv.c | 6 ++++ > drivers/gpu/drm/tilcdc/tilcdc_drv.c | 11 +++++- > drivers/gpu/drm/tiny/bochs.c | 6 ++++ > drivers/gpu/drm/tiny/cirrus.c | 6 ++++ > drivers/gpu/drm/tve200/tve200_drv.c | 7 ++++ > drivers/gpu/drm/vboxvideo/vbox_drv.c | 10 ++++++ > drivers/gpu/drm/vc4/vc4_drv.c | 36 ++++++++++++------- > 30 files changed, 217 insertions(+), 14 deletions(-) Just a heads up to keep folks in the loop: I've landed the first patch in the drm-misc series, AKA ("drm/atomic-helper: drm_atomic_helper_shutdown(NULL) should be a noop"), but I haven't landed any of the others yet. I'm going to give them another ~week just to be sure there are no objections. -Doug
NOTE: in order to avoid email sending limits on the cover letter, I've split this patch series in two. Patches that target drm-misc and ones that don't. The cover letter of the two is identical other than this note. This patch series came about after a _long_ discussion between me and Maxime Ripard in response to a different patch I sent out [1]. As part of that discussion, we realized that it would be good if DRM drivers consistently called drm_atomic_helper_shutdown() properly at shutdown and driver remove time as it's documented that they should do. The eventual goal of this would be to enable removing some hacky code from panel drivers where they had to hook into shutdown themselves because the DRM driver wasn't calling them. It turns out that quite a lot of drivers seemed to be missing drm_atomic_helper_shutdown() in one or both places that it was supposed to be. This patch series attempts to fix all the drivers that I was able to identify. NOTE: fixing this wasn't exactly cookie cutter. Each driver has its own unique way of setting itself up and tearing itself down. Some drivers also use the component model, which adds extra fun. I've made my best guess at solving this and I've run a bunch of compile tests (specifically, allmodconfig for amd64, arm64, and powerpc). That being said, these code changes are not totally trivial and I've done zero real testing on them. Making these patches was also a little mind numbing and I'm certain my eyes glazed over at several points when writing them. What I'm trying to say is to please double-check that I didn't do anything too silly, like cast your driver's drvdata to the wrong type. Even better, test these patches! I've organized this series like this: 1. One patch for all simple cases of just needing a call at shutdown time for drivers that go through drm-misc. 2. A separate patch for "drm/vc4", even though it goes through drm-misc, since I wanted to leave an extra note for that one. 3. Patches for drivers that just needed a call at shutdown time for drivers that _don't_ go through drm-misc. 4. Patches for the few drivers that had the call at shutdown time but lacked it at remove time. 5. One patch for all simple cases of needing a call at shutdown and remove (or unbind) time for drivers that go through drm-misc. 6. A separate patch for "drm/hisilicon/kirin", even though it goes through drm-misc, since I wanted to leave an extra note for that one. 7. Patches for drivers that needed a call at shutdown and remove (or unbind) time for drivers that _don't_ go through drm-misc. I've labeled this patch series as RFT (request for testing) to help call attention to the fact that I didn't personally test any of these patches. If you're a maintainer of one of these drivers and you think that the patch for your driver looks fabulous, you've tested it, and you'd like to land it right away then please do. For non-drm-misc drivers there are no dependencies here. Some of the drm-misc drivers depend on the first patch, AKA ("drm/atomic-helper: drm_atomic_helper_shutdown(NULL) should be a noop"). I've tried to call this out but it also should be obvious once you know to look for it. I'd like to call out a few drivers that I _didn't_ fix in this series and why. If any of these drivers should be fixed then please yell. - DRM driers backed by usb_driver (like gud, gm12u320, udl): I didn't add the call to drm_atomic_helper_shutdown() at shutdown time because there's no ".shutdown" callback for them USB drivers. Given that USB is hotpluggable, I'm assuming that they are robust against this and the special shutdown callback isn't needed. - ofdrm and simpledrm: These didn't have drm_atomic_helper_shutdown() in either shutdown or remove, but I didn't add it. I think that's OK since they're sorta special and not really directly controlling hardware power sequencing. - virtio, vkms, vmwgfx, xen: I believe these are all virtual (thus they wouldn't directly drive a panel) and adding the shutdown didn't look straightforward, so I skipped them. I've let each patch in the series get CCed straight from get_maintainer. That means not everyone will have received every patch but everyone should be on the cover letter. I know some people dislike this but when touching this many drivers there's not much choice. dri-devel and lkml have been CCed and lore/lei exist, so hopefully that's enough for folks. I'm happy to add people to the whole series for future posts. [1] https://lore.kernel.org/lkml/20230804140605.RFC.4.I930069a32baab6faf46d6b234f89613b5cec0f14@changeid Douglas Anderson (6): drm/atomic-helper: drm_atomic_helper_shutdown(NULL) should be a noop drm: Call drm_atomic_helper_shutdown() at shutdown time for misc drivers drm/vc4: Call drm_atomic_helper_shutdown() at shutdown time drm/ssd130x: Call drm_atomic_helper_shutdown() at remove time drm: Call drm_atomic_helper_shutdown() at shutdown/remove time for misc drivers drm/hisilicon/kirin: Call drm_atomic_helper_shutdown() at shutdown/unbind time .../gpu/drm/arm/display/komeda/komeda_drv.c | 9 +++++ .../gpu/drm/arm/display/komeda/komeda_kms.c | 7 ++++ .../gpu/drm/arm/display/komeda/komeda_kms.h | 1 + drivers/gpu/drm/arm/hdlcd_drv.c | 6 ++++ drivers/gpu/drm/arm/malidp_drv.c | 6 ++++ drivers/gpu/drm/aspeed/aspeed_gfx_drv.c | 7 ++++ drivers/gpu/drm/ast/ast_drv.c | 6 ++++ drivers/gpu/drm/atmel-hlcdc/atmel_hlcdc_dc.c | 6 ++++ drivers/gpu/drm/drm_atomic_helper.c | 3 ++ drivers/gpu/drm/fsl-dcu/fsl_dcu_drm_drv.c | 8 +++++ .../gpu/drm/hisilicon/hibmc/hibmc_drm_drv.c | 6 ++++ .../gpu/drm/hisilicon/kirin/kirin_drm_drv.c | 9 +++++ drivers/gpu/drm/hyperv/hyperv_drm_drv.c | 6 ++++ drivers/gpu/drm/logicvc/logicvc_drm.c | 9 +++++ drivers/gpu/drm/loongson/lsdc_drv.c | 6 ++++ drivers/gpu/drm/mcde/mcde_drv.c | 9 +++++ drivers/gpu/drm/mgag200/mgag200_drv.c | 8 +++++ drivers/gpu/drm/omapdrm/omap_drv.c | 8 +++++ drivers/gpu/drm/pl111/pl111_drv.c | 7 ++++ drivers/gpu/drm/qxl/qxl_drv.c | 7 ++++ drivers/gpu/drm/solomon/ssd130x.c | 1 + drivers/gpu/drm/sti/sti_drv.c | 7 ++++ drivers/gpu/drm/stm/drv.c | 7 ++++ drivers/gpu/drm/sun4i/sun4i_drv.c | 6 ++++ drivers/gpu/drm/tilcdc/tilcdc_drv.c | 11 +++++- drivers/gpu/drm/tiny/bochs.c | 6 ++++ drivers/gpu/drm/tiny/cirrus.c | 6 ++++ drivers/gpu/drm/tve200/tve200_drv.c | 7 ++++ drivers/gpu/drm/vboxvideo/vbox_drv.c | 10 ++++++ drivers/gpu/drm/vc4/vc4_drv.c | 36 ++++++++++++------- 30 files changed, 217 insertions(+), 14 deletions(-)