[PATCH v3 00/79] Address some issues with PM runtime at media subsystem

From: Mauro Carvalho Chehab
Date: Tue Apr 27 2021 - 06:34:55 EST

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During the review of the patches from unm.edu, one of the patterns
I noticed is the amount of patches trying to fix pm_runtime_get_sync()
calls.

After analyzing the feedback from version 1 of this series, I noticed
a few other weird behaviors at the PM runtime resume code. So, this
series start addressing some bugs and issues at the current code.
Then, it gets rid of pm_runtime_get_sync() at the media subsystem
(with 2 exceptions).

It should be noticed that
Commit dd8088d5a896 ("PM: runtime: Add pm_runtime_resume_and_get to deal with usage counter")
added a new method to does a pm_runtime get, which increments
the usage count only on success.

The rationale of getting rid of pm_runtime_get_sync() is:

1. despite its name, this is actually a PM runtime resume call,
but some developers didn't seem to realize that, as I got this
pattern on some drivers:

pm_runtime_get_sync(&client->dev);
pm_runtime_disable(&client->dev);
pm_runtime_set_suspended(&client->dev);
pm_runtime_put_noidle(&client->dev);

It makes no sense to resume PM just to suspend it again ;-)

2. Usual *_get() methods only increment their use count on success,
but pm_runtime_get_sync() increments it unconditionally. Due to
that, several drivers were mistakenly not calling
pm_runtime_put_noidle() when it fails;

3. The name of the new variant is a lot clearer:
pm_runtime_resume_and_get()
As its same clearly says that this is a PM runtime resume function,
that also increments the usage counter on success;

4. Consistency: we did similar changes subsystem wide with
for instance strlcpy() and strcpy() that got replaced by
strscpy(). Having all drivers using the same known-to-be-safe
methods is a good thing;

5. Prevent newer drivers to copy-and-paste a code that it would
be easier to break if they don't truly understand what's behind
the scenes.

This series replace places pm_runtime_get_sync(), by calling
pm_runtime_resume_and_get() instead.

This should help to avoid future mistakes like that, as people
tend to use the existing drivers as examples for newer ones.

compile-tested only.

Patches 1 to 7 fix some issues that already exists at the current
PM runtime code;

patches 8 to 20 fix some usage_count problems that still exists
at the media subsystem;

patches 21 to 78 repaces pm_runtime_get_sync() by
pm_runtime_resume_and_get();

Patch 79 (and a hunk on patch 78) documents the two exceptions
where pm_runtime_get_sync() will still be used for now.

---

v3: - fix a compilation error;
v2: - addressed pointed issues and fixed a few other PM issues.

Mauro Carvalho Chehab (79):
media: venus: fix PM runtime logic at venus_sys_error_handler()
media: i2c: ccs-core: return the right error code at suspend
media: i2c: mt9m001: don't resume at remove time
media: i2c: ov7740: don't resume at remove time
media: i2c: video-i2c: don't resume at remove time
media: exynos-gsc: don't resume at remove time
media: atmel: properly get pm_runtime
media: marvel-ccic: fix some issues when getting pm_runtime
media: mdk-mdp: fix pm_runtime_get_sync() usage count
media: rcar_fdp1: fix pm_runtime_get_sync() usage count
media: rga-buf: use pm_runtime_resume_and_get()
media: renesas-ceu: Properly check for PM errors
media: s5p: fix pm_runtime_get_sync() usage count
media: am437x: fix pm_runtime_get_sync() usage count
media: sh_vou: fix pm_runtime_get_sync() usage count
media: mtk-vcodec: fix pm_runtime_get_sync() usage count
media: s5p-jpeg: fix pm_runtime_get_sync() usage count
media: delta-v4l2: fix pm_runtime_get_sync() usage count
media: sun8i_rotate: fix pm_runtime_get_sync() usage count
staging: media: rkvdec: fix pm_runtime_get_sync() usage count
staging: media: atomisp_fops: use pm_runtime_resume_and_get()
staging: media: imx7-mipi-csis: use pm_runtime_resume_and_get()
staging: media: ipu3: use pm_runtime_resume_and_get()
staging: media: cedrus_video: use pm_runtime_resume_and_get()
staging: media: vde: use pm_runtime_resume_and_get()
staging: media: csi: use pm_runtime_resume_and_get()
staging: media: vi: use pm_runtime_resume_and_get()
media: i2c: ak7375: use pm_runtime_resume_and_get()
media: i2c: ccs-core: use pm_runtime_resume_and_get()
media: i2c: dw9714: use pm_runtime_resume_and_get()
media: i2c: dw9768: use pm_runtime_resume_and_get()
media: i2c: dw9807-vcm: use pm_runtime_resume_and_get()
media: i2c: hi556: use pm_runtime_resume_and_get()
media: i2c: imx214: use pm_runtime_resume_and_get()
media: i2c: imx219: use pm_runtime_resume_and_get()
media: i2c: imx258: use pm_runtime_resume_and_get()
media: i2c: imx274: use pm_runtime_resume_and_get()
media: i2c: imx290: use pm_runtime_resume_and_get()
media: i2c: imx319: use pm_runtime_resume_and_get()
media: i2c: imx334: use pm_runtime_resume_and_get()
media: i2c: imx355: use pm_runtime_resume_and_get()
media: i2c: mt9m001: use pm_runtime_resume_and_get()
media: i2c: ov02a10: use pm_runtime_resume_and_get()
media: i2c: ov13858: use pm_runtime_resume_and_get()
media: i2c: ov2659: use pm_runtime_resume_and_get()
media: i2c: ov2685: use pm_runtime_resume_and_get()
media: i2c: ov2740: use pm_runtime_resume_and_get()
media: i2c: ov5647: use pm_runtime_resume_and_get()
media: i2c: ov5648: use pm_runtime_resume_and_get()
media: i2c: ov5670: use pm_runtime_resume_and_get()
media: i2c: ov5675: use pm_runtime_resume_and_get()
media: i2c: ov5695: use pm_runtime_resume_and_get()
media: i2c: ov7740: use pm_runtime_resume_and_get()
media: i2c: ov8856: use pm_runtime_resume_and_get()
media: i2c: ov8865: use pm_runtime_resume_and_get()
media: i2c: ov9734: use pm_runtime_resume_and_get()
media: i2c: tvp5150: use pm_runtime_resume_and_get()
media: i2c: video-i2c: use pm_runtime_resume_and_get()
media: sti/hva: use pm_runtime_resume_and_get()
media: ipu3: use pm_runtime_resume_and_get()
media: coda: use pm_runtime_resume_and_get()
media: exynos4-is: use pm_runtime_resume_and_get()
media: exynos-gsc: use pm_runtime_resume_and_get()
media: mtk-jpeg: use pm_runtime_resume_and_get()
media: camss: use pm_runtime_resume_and_get()
media: venus: use pm_runtime_resume_and_get()
media: venus: vdec: use pm_runtime_resume_and_get()
media: venus: venc: use pm_runtime_resume_and_get()
media: rcar-fcp: use pm_runtime_resume_and_get()
media: rkisp1: use pm_runtime_resume_and_get()
media: s3c-camif: use pm_runtime_resume_and_get()
media: s5p-mfc: use pm_runtime_resume_and_get()
media: bdisp-v4l2: use pm_runtime_resume_and_get()
media: stm32: use pm_runtime_resume_and_get()
media: sunxi: use pm_runtime_resume_and_get()
media: ti-vpe: use pm_runtime_resume_and_get()
media: vsp1: use pm_runtime_resume_and_get()
media: rcar-vin: use pm_runtime_resume_and_get()
media: hantro: document the usage of pm_runtime_get_sync()

drivers/media/cec/platform/s5p/s5p_cec.c | 5 +++-
drivers/media/i2c/ak7375.c | 10 +------
drivers/media/i2c/ccs/ccs-core.c | 18 +++++-------
drivers/media/i2c/dw9714.c | 10 +------
drivers/media/i2c/dw9768.c | 10 +------
drivers/media/i2c/dw9807-vcm.c | 10 +------
drivers/media/i2c/hi556.c | 3 +-
drivers/media/i2c/imx214.c | 6 ++--
drivers/media/i2c/imx219.c | 6 ++--
drivers/media/i2c/imx258.c | 6 ++--
drivers/media/i2c/imx274.c | 3 +-
drivers/media/i2c/imx290.c | 6 ++--
drivers/media/i2c/imx319.c | 6 ++--
drivers/media/i2c/imx334.c | 5 ++--
drivers/media/i2c/imx355.c | 6 ++--
drivers/media/i2c/mt9m001.c | 8 ++----
drivers/media/i2c/ov02a10.c | 6 ++--
drivers/media/i2c/ov13858.c | 6 ++--
drivers/media/i2c/ov2659.c | 6 ++--
drivers/media/i2c/ov2685.c | 7 ++---
drivers/media/i2c/ov2740.c | 6 ++--
drivers/media/i2c/ov5647.c | 9 +++---
drivers/media/i2c/ov5648.c | 6 ++--
drivers/media/i2c/ov5670.c | 6 ++--
drivers/media/i2c/ov5675.c | 3 +-
drivers/media/i2c/ov5695.c | 6 ++--
drivers/media/i2c/ov7740.c | 8 ++----
drivers/media/i2c/ov8856.c | 3 +-
drivers/media/i2c/ov8865.c | 6 ++--
drivers/media/i2c/ov9734.c | 3 +-
drivers/media/i2c/tvp5150.c | 16 ++---------
drivers/media/i2c/video-i2c.c | 14 +++-------
drivers/media/pci/intel/ipu3/ipu3-cio2-main.c | 3 +-
drivers/media/platform/am437x/am437x-vpfe.c | 22 +++++++++++----
drivers/media/platform/atmel/atmel-isc-base.c | 27 +++++++++++++-----
drivers/media/platform/atmel/atmel-isi.c | 19 ++++++++++---
drivers/media/platform/coda/coda-common.c | 5 ++--
drivers/media/platform/exynos-gsc/gsc-core.c | 3 --
drivers/media/platform/exynos-gsc/gsc-m2m.c | 2 +-
.../media/platform/exynos4-is/fimc-capture.c | 6 ++--
drivers/media/platform/exynos4-is/fimc-is.c | 4 +--
.../platform/exynos4-is/fimc-isp-video.c | 3 +-
drivers/media/platform/exynos4-is/fimc-isp.c | 7 ++---
drivers/media/platform/exynos4-is/fimc-lite.c | 5 ++--
drivers/media/platform/exynos4-is/fimc-m2m.c | 2 +-
drivers/media/platform/exynos4-is/media-dev.c | 8 ++----
drivers/media/platform/exynos4-is/mipi-csis.c | 8 ++----
.../media/platform/marvell-ccic/mcam-core.c | 9 ++++--
.../media/platform/mtk-jpeg/mtk_jpeg_core.c | 4 +--
drivers/media/platform/mtk-mdp/mtk_mdp_m2m.c | 6 ++--
.../platform/mtk-vcodec/mtk_vcodec_dec_pm.c | 4 +--
.../media/platform/qcom/camss/camss-csid.c | 6 ++--
.../media/platform/qcom/camss/camss-csiphy.c | 6 ++--
.../media/platform/qcom/camss/camss-ispif.c | 6 ++--
drivers/media/platform/qcom/camss/camss-vfe.c | 5 ++--
drivers/media/platform/qcom/venus/core.c | 28 +++++++++++--------
.../media/platform/qcom/venus/pm_helpers.c | 10 +++----
drivers/media/platform/qcom/venus/vdec.c | 4 +--
drivers/media/platform/qcom/venus/venc.c | 5 ++--
drivers/media/platform/rcar-fcp.c | 6 ++--
drivers/media/platform/rcar-vin/rcar-csi2.c | 6 ++++
drivers/media/platform/rcar-vin/rcar-dma.c | 6 ++--
drivers/media/platform/rcar-vin/rcar-v4l2.c | 6 ++--
drivers/media/platform/rcar_fdp1.c | 12 ++++++--
drivers/media/platform/renesas-ceu.c | 4 +--
drivers/media/platform/rockchip/rga/rga-buf.c | 3 +-
drivers/media/platform/rockchip/rga/rga.c | 4 ++-
.../platform/rockchip/rkisp1/rkisp1-capture.c | 3 +-
.../media/platform/s3c-camif/camif-capture.c | 2 +-
drivers/media/platform/s3c-camif/camif-core.c | 5 ++--
drivers/media/platform/s5p-jpeg/jpeg-core.c | 2 +-
drivers/media/platform/s5p-mfc/s5p_mfc_pm.c | 6 ++--
drivers/media/platform/sh_vou.c | 6 +++-
drivers/media/platform/sti/bdisp/bdisp-v4l2.c | 7 +++--
drivers/media/platform/sti/delta/delta-v4l2.c | 4 +--
drivers/media/platform/sti/hva/hva-hw.c | 17 +++++------
drivers/media/platform/stm32/stm32-dcmi.c | 5 ++--
.../platform/sunxi/sun4i-csi/sun4i_v4l2.c | 6 ++--
.../sunxi/sun8i-rotate/sun8i_rotate.c | 2 +-
drivers/media/platform/ti-vpe/cal-video.c | 4 ++-
drivers/media/platform/ti-vpe/cal.c | 8 ++++--
drivers/media/platform/ti-vpe/vpe.c | 4 +--
drivers/media/platform/vsp1/vsp1_drv.c | 6 ++--
.../staging/media/atomisp/pci/atomisp_fops.c | 6 ++--
drivers/staging/media/hantro/hantro_drv.c | 7 +++++
drivers/staging/media/imx/imx7-mipi-csis.c | 7 ++---
drivers/staging/media/ipu3/ipu3.c | 3 +-
drivers/staging/media/rkvdec/rkvdec.c | 2 +-
.../staging/media/sunxi/cedrus/cedrus_video.c | 6 ++--
drivers/staging/media/tegra-vde/vde.c | 16 +++++++----
drivers/staging/media/tegra-video/csi.c | 3 +-
drivers/staging/media/tegra-video/vi.c | 3 +-
92 files changed, 298 insertions(+), 335 deletions(-)

--
2.30.2

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