From 08c78e9d61a857c9077240e7ddb67550c6f96d06 Mon Sep 17 00:00:00 2001 From: Tony Lindgren Date: Fri, 12 Feb 2016 08:56:52 -0800 Subject: [PATCH] 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 Cc: Nishanth Menon Cc: Rafael J. Wysocki Cc: Tero Kristo Acked-by: Kevin Hilman Acked-by: Ulf Hansson Signed-off-by: Tony Lindgren --- 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 0437537751bc..ebd83690ba48 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); } -- 2.20.1