usb: typec: ucsi: acpi: Check the _DEP dependencies

Failing probe with -EPROBE_DEFER until all dependencies
listed in the _DEP (Operation Region Dependencies) object
have been met.

This will fix an issue where on some platforms UCSI ACPI
driver fails to probe because the address space handler for
the operation region that the UCSI ACPI interface uses has
not been loaded yet.

Fixes: 8243edf44152 ("usb: typec: ucsi: Add ACPI driver")
Cc: stable@vger.kernel.org
Signed-off-by: Heikki Krogerus <heikki.krogerus@linux.intel.com>
Link: https://lore.kernel.org/r/20200904110918.51546-1-heikki.krogerus@linux.intel.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

diff --git a/drivers/usb/typec/ucsi/ucsi_acpi.c b/drivers/usb/typec/ucsi/ucsi_acpi.c
index 9fc4f33..c0aca2f 100644 (file)
--- a/drivers/usb/typec/ucsi/ucsi_acpi.c
+++ b/drivers/usb/typec/ucsi/ucsi_acpi.c
@@ -112,11 +112,15 @@ static void ucsi_acpi_notify(acpi_handle handle, u32 event, void *data)
 
 static int ucsi_acpi_probe(struct platform_device *pdev)
 {
+       struct acpi_device *adev = ACPI_COMPANION(&pdev->dev);
        struct ucsi_acpi *ua;
        struct resource *res;
        acpi_status status;
        int ret;
 
+       if (adev->dep_unmet)
+               return -EPROBE_DEFER;
+
        ua = devm_kzalloc(&pdev->dev, sizeof(*ua), GFP_KERNEL);
        if (!ua)
                return -ENOMEM;