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

commit 1f3546ff3f0a1000971daef58406954bad3f7061 upstream.

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 a18112a83faed2df09e49c0a5a93d2fce0823c5f..dda8bd39c9186624cf727f7cec2c5cb8452da27c 100644 (file)
--- a/drivers/usb/typec/ucsi/ucsi_acpi.c
+++ b/drivers/usb/typec/ucsi/ucsi_acpi.c
@@ -64,11 +64,15 @@ 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;