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author | Tony Lindgren <tony@atomide.com> | 2016-02-12 16:56:52 (GMT) |
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committer | Tony Lindgren <tony@atomide.com> | 2016-02-12 16:56:52 (GMT) |
commit | 08c78e9d61a857c9077240e7ddb67550c6f96d06 (patch) | |
tree | ac71be08409c23eb6e2861e6c43aadcb9288e1a0 | |
parent | bf26927b2c0780609e6e5361d177cf10107065f3 (diff) | |
download | linux-08c78e9d61a857c9077240e7ddb67550c6f96d06.tar.xz |
ARM: OMAP2+: Improve omap_device error for driver writers
Drivers using pm_runtime_use_autosuspend() may not get disabled after
-EPROBE_DEFER. On the following device driver probe, hardware state
is different from the PM runtime state causing omap_device to produce
the following error:
omap_device_enable() called from invalid state 1
And with omap_device and omap hardware being picky for PM, this will
block any deeper idle states in hardware.
Let's add a proper error message so driver writers can easily fix
their drivers for PM.
In general, the solution is to fix the drivers to follow the PM
runtime documentation:
1. For sections of code that needs the device disabled, use
pm_runtime_put_sync_suspend() if pm_runtime_set_autosuspend() has
been set.
2. For driver exit code, use pm_runtime_dont_use_autosuspend() before
pm_runtime_put_sync() if pm_runtime_use_autosuspend() has been
set.
Let's not return with 0 from _od_runtime_resume() as that will
eventually lead into new drivers with broken PM runtime that will
block deeper idle states on omaps.
Cc: Alan Stern <stern@rowland.harvard.edu>
Cc: Nishanth Menon <nm@ti.com>
Cc: Rafael J. Wysocki <rafael@kernel.org>
Cc: Tero Kristo <t-kristo@ti.com>
Acked-by: Kevin Hilman <khilman@baylibre.com>
Acked-by: Ulf Hansson <ulf.hansson@linaro.org>
Signed-off-by: Tony Lindgren <tony@atomide.com>
-rw-r--r-- | arch/arm/mach-omap2/omap_device.c | 4 |
1 files changed, 3 insertions, 1 deletions
diff --git a/arch/arm/mach-omap2/omap_device.c b/arch/arm/mach-omap2/omap_device.c index 0437537..ebd8369 100644 --- a/arch/arm/mach-omap2/omap_device.c +++ b/arch/arm/mach-omap2/omap_device.c @@ -602,8 +602,10 @@ static int _od_runtime_resume(struct device *dev) int ret; ret = omap_device_enable(pdev); - if (ret) + if (ret) { + dev_err(dev, "use pm_runtime_put_sync_suspend() in driver?\n"); return ret; + } return pm_generic_runtime_resume(dev); } |