| Message ID | 29a5f9cf9680a36fc1f6277364aa7c53776ed0cc.1619518193.git.mchehab+huawei@kernel.org (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | None | expand |
diff --git a/drivers/staging/media/hantro/hantro_drv.c b/drivers/staging/media/hantro/hantro_drv.c index 595e82a82728..96f940c1c85c 100644 --- a/drivers/staging/media/hantro/hantro_drv.c +++ b/drivers/staging/media/hantro/hantro_drv.c @@ -155,6 +155,13 @@ static void device_run(void *priv) ret = clk_bulk_enable(ctx->dev->variant->num_clocks, ctx->dev->clocks); if (ret) goto err_cancel_job; + + /* + * The pm_runtime_get_sync() will increment dev->power.usage_count, + * even on errors. That's the expected behavior here, since the + * hantro_job_finish() function at the error handling code + * will internally call pm_runtime_put_autosuspend(). + */ ret = pm_runtime_get_sync(ctx->dev->dev); if (ret < 0) goto err_cancel_job;
Despite other *_get()/*_put() functions, where usage count is incremented only if not errors, the pm_runtime_get_sync() has a different behavior, incrementing the counter *even* on errors. That's an error prone behavior, as people often forget to decrement the usage counter. However, the hantro driver depends on this behavior, as it will decrement the usage_count unconditionally at the m2m job finish time, which makes sense. So, intead of using the pm_runtime_resume_and_get() that would decrement the counter on error, keep the current API, but add a documentation explaining the rationale for keep using pm_runtime_get_sync(). Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org> --- drivers/staging/media/hantro/hantro_drv.c | 7 +++++++ 1 file changed, 7 insertions(+)