[PATCH 7/7] ARM: OMAP2+: Fix omap_device for module reload on PM runtime forbid

Kevin Hilman khilman at baylibre.com
Thu Feb 11 17:13:37 PST 2016


Tony Lindgren <tony at atomide.com> writes:

> 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 <stern at rowland.harvard.edu>
> Cc: Kevin Hilman <khilman at baylibre.com>
> Cc: Nishanth Menon <nm at ti.com>
> Cc: Rafael J. Wysocki <rafael at kernel.org>
> Cc: Tero Kristo <t-kristo at ti.com>
> Reported-by: Ulf Hansson <ulf.hansson at linaro.org>
> Signed-off-by: Tony Lindgren <tony at atomide.com>

Acked-by: Kevin Hilman <khilman at baylibre.com>

> ---
>  arch/arm/mach-omap2/omap_device.c | 10 ++++++++++
>  1 file changed, 10 insertions(+)
>
> diff --git a/arch/arm/mach-omap2/omap_device.c b/arch/arm/mach-omap2/omap_device.c
> index ebd8369..f7ff3b9 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);



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