| Message ID | 1455145370-20301-7-git-send-email-tony@atomide.com |
|---|---|
| State | Not Applicable |
| Headers | show |
Tony Lindgren <tony@atomide.com> writes: > 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: Kevin Hilman <khilman@baylibre.com> > Cc: Nishanth Menon <nm@ti.com> > Cc: Rafael J. Wysocki <rafael@kernel.org> > Cc: Ulf Hansson <ulf.hansson@linaro.org> > Cc: Tero Kristo <t-kristo@ti.com> > Signed-off-by: Tony Lindgren <tony@atomide.com> Acked-by: Kevin Hilman <khilman@baylibre.com> > --- > arch/arm/mach-omap2/omap_device.c | 4 +++- > 1 file changed, 3 insertions(+), 1 deletion(-) > > 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); > } -- To unsubscribe from this list: send the line "unsubscribe linux-i2c" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
On 11 February 2016 at 00:02, Tony Lindgren <tony@atomide.com> wrote: > 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: Kevin Hilman <khilman@baylibre.com> > Cc: Nishanth Menon <nm@ti.com> > Cc: Rafael J. Wysocki <rafael@kernel.org> > Cc: Ulf Hansson <ulf.hansson@linaro.org> > Cc: Tero Kristo <t-kristo@ti.com> > Signed-off-by: Tony Lindgren <tony@atomide.com> Acked-by: Ulf Hansson <ulf.hansson@linaro.org> Kind regards Uffe > --- > arch/arm/mach-omap2/omap_device.c | 4 +++- > 1 file changed, 3 insertions(+), 1 deletion(-) > > 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); > } > -- > 2.7.0 > -- To unsubscribe from this list: send the line "unsubscribe linux-i2c" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
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); }
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: Kevin Hilman <khilman@baylibre.com> Cc: Nishanth Menon <nm@ti.com> Cc: Rafael J. Wysocki <rafael@kernel.org> Cc: Ulf Hansson <ulf.hansson@linaro.org> Cc: Tero Kristo <t-kristo@ti.com> Signed-off-by: Tony Lindgren <tony@atomide.com> --- arch/arm/mach-omap2/omap_device.c | 4 +++- 1 file changed, 3 insertions(+), 1 deletion(-)