On Tue, Nov 28, 2017 at 1:19 AM, Stefan Brüns stefan.bruens@rwth-aachen.de wrote:
On Monday, November 27, 2017 4:35:02 PM CET Maxime Ripard wrote:
Hi,
On Mon, Nov 27, 2017 at 01:17:25PM +0100, Stefan Brüns wrote:
Include the OF-based modalias in the uevent sent when registering devices on the sunxi RSB bus, so that user space has a chance to autoload the kernel module for the device.
Fixes a regression caused by commit 3f241bfa60bd ("arm64: allwinner: a64: pine64: Use dcdc1 regulator for mmc0"). When the axp20x-rsb module for the AXP803 PMIC is built as a module, it is not loaded and the system ends up with an disfunctional MMC controller.
Cc: stable stable@vger.kernel.org Signed-off-by: Stefan Brüns stefan.bruens@rwth-aachen.de
drivers/bus/sunxi-rsb.c | 13 +++++++++++++ 1 file changed, 13 insertions(+)
diff --git a/drivers/bus/sunxi-rsb.c b/drivers/bus/sunxi-rsb.c index 328ca93781cf..37cb57244cbe 100644 --- a/drivers/bus/sunxi-rsb.c +++ b/drivers/bus/sunxi-rsb.c @@ -173,11 +173,24 @@ static int sunxi_rsb_device_remove(struct device *dev)> return drv->remove(to_sunxi_rsb_device(dev));
}
+static int sunxi_rsb_device_uevent(struct device *dev,
struct kobj_uevent_env *env)+{
- int ret;
- ret = of_device_uevent_modalias(dev, env);
- if (ret != -ENODEV)
return ret;A comment explaining why we need to ignore the ENODEV error code would be great here.
Lazy answer - everyone else is doing the same, and nobody cared to add an explanation.
For *some* drivers, this is likely because the same device may be enumerated from e.g ACPI or OF, and for an ACPI device -ENODEV will be returned, as dev->of_node is NULL.
For devices which are only usable in an OF context, this is bogus. Not sure about sunxi-rsb.
sunxi-rsb (and Allwinner support in mainline in general) is OF only. With the exception of mfd sub-devices, if someone is enumerating devices in some other fashion, it should rightly blow up in their face.
- return 0;
+}
static struct bus_type sunxi_rsb_bus = {
.name = RSB_CTRL_NAME, .match = sunxi_rsb_device_match, .probe = sunxi_rsb_device_probe, .remove = sunxi_rsb_device_remove,
- .uevent = sunxi_rsb_device_uevent,
Any reason to not use of_device_uevent_modalias directly here?
*If* sunxi-rsb can be used without OF, then yes, otherwise no.
You can just use of_device_uevent_modalias, like the other OF platforms.
ChenYu