From 08c78e9d61a857c9077240e7ddb67550c6f96d06 Mon Sep 17 00:00:00 2001 From: Tony Lindgren Date: Fri, 12 Feb 2016 08:56:52 -0800 Subject: 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(-) (limited to 'arch/arm/mach-omap2/omap_device.c') 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); } -- cgit v1.2.3 From cf26f1137333251f3515dea31f95775b99df0fd5 Mon Sep 17 00:00:00 2001 From: Tony Lindgren Date: Fri, 12 Feb 2016 08:56:52 -0800 Subject: ARM: OMAP2+: Fix omap_device for module reload on PM runtime forbid If a driver PM runtime is disabled via sysfs, and the module is unloaded, PM runtime can't do anything to disable the device. Let's let the interconnect disable the device on BUS_NOTIFY_UNBOUND_DRIVER. Otherwise omap_device will produce and error on the following module reload. This can be easily tested with something like: # modprobe omap_hsmmc # echo on > /sys/devices/platform/68000000.ocp/4809c000.mmc/power/control # rmmod omap_hsmmc # modprobe omap_hsmmc Cc: Alan Stern Cc: Nishanth Menon Cc: Rafael J. Wysocki Cc: Tero Kristo Reported-by: Ulf Hansson Acked-by: Kevin Hilman Acked-by: Ulf Hansson Signed-off-by: Tony Lindgren --- arch/arm/mach-omap2/omap_device.c | 10 ++++++++++ 1 file changed, 10 insertions(+) (limited to 'arch/arm/mach-omap2/omap_device.c') diff --git a/arch/arm/mach-omap2/omap_device.c b/arch/arm/mach-omap2/omap_device.c index ebd83690ba48..f7ff3b9dad87 100644 --- a/arch/arm/mach-omap2/omap_device.c +++ b/arch/arm/mach-omap2/omap_device.c @@ -191,12 +191,22 @@ static int _omap_device_notifier_call(struct notifier_block *nb, { struct platform_device *pdev = to_platform_device(dev); struct omap_device *od; + int err; switch (event) { case BUS_NOTIFY_DEL_DEVICE: if (pdev->archdata.od) omap_device_delete(pdev->archdata.od); break; + case BUS_NOTIFY_UNBOUND_DRIVER: + od = to_omap_device(pdev); + if (od && (od->_state == OMAP_DEVICE_STATE_ENABLED)) { + dev_info(dev, "enabled after unload, idling\n"); + err = omap_device_idle(pdev); + if (err) + dev_err(dev, "failed to idle\n"); + } + break; case BUS_NOTIFY_ADD_DEVICE: if (pdev->dev.of_node) omap_device_build_from_dt(pdev); -- cgit v1.2.3