[PATCH AUTOSEL for 4.14 004/161] ACPI / LPSS: Do not instiate platform_dev for devs without MMIO resources

Sasha Levin
2018-04-09T00:22:04Z

From: Hans de Goede <hdegoede@redhat.com>

[ Upstream commit e1681599345b8466786b6e54a2db2a00a068a3f3 ]

acpi_lpss_create_device() skips handling LPSS devices which do not have
a mmio resources in their resource list (typically these devices are
disabled by the firmware). But since the LPSS code does not bind to the
device, acpi_bus_attach() ends up still creating a platform device for
it and the regular platform_driver for the ACPI HID still tries to bind
to it.

This happens e.g. on some boards which do not use the pwm-controller
and have an empty or invalid resource-table for it. Currently this causes
these error messages to get logged:

[ 3.281966] pwm-lpss 80862288:00: invalid resource
[ 3.287098] pwm-lpss: probe of 80862288:00 failed with error -22

This commit stops the undesirable creation of a platform_device for
disabled LPSS devices by setting pnp.type.platform_id to 0. Note that
acpi_scan_attach_handler() also sets pnp.type.platform_id to 0 when there
is a matching handler for the device and that handler has no attach
callback, so we simply behave as a handler without an attach function
in this case.

Signed-off-by: Hans de Goede <hdegoede@redhat.com>
Acked-by: Mika Westerberg <mika.westerberg@linux.intel.com>
Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Signed-off-by: Sasha Levin <alexander.levin@microsoft.com>
---
drivers/acpi/acpi_lpss.c | 2 ++
1 file changed, 2 insertions(+)

diff --git a/drivers/acpi/acpi_lpss.c b/drivers/acpi/acpi_lpss.c
index 032ae44710e5..a2be3fd2c72b 100644
--- a/drivers/acpi/acpi_lpss.c
+++ b/drivers/acpi/acpi_lpss.c
@@ -465,6 +465,8 @@ static int acpi_lpss_create_device(struct acpi_device *adev,
acpi_dev_free_resource_list(&resource_list);

if (!pdata->mmio_base) {
+ /* Avoid acpi_bus_attach() instantiating a pdev for this dev. */
+ adev->pnp.type.platform_id = 0;
/* Skip the device, but continue the namespace scan. */
ret = 0;
goto err_out;
--
2.15.1