Commit f706a63f authored by Rafael J. Wysocki's avatar Rafael J. Wysocki
Browse files

ACPI: TAD: Use DC wakeup only if AC wakeup is supported 

According to Section 9.17.2 of ACPI 6.6 [1], setting ACPI_TAD_DC_WAKE in
the capabilities without setting ACPI_TAD_AC_WAKE is invalid, so don't
support wakeup if that's the case.

Moreover, it is sufficient to check ACPI_TAD_AC_WAKE alone to determine
if wakeup is supported at all, so use this observation to simplify one
check.

Link: https://uefi.org/specs/ACPI/6.6/09_ACPI_Defined_Devices_and_Device_Specific_Objects.html#gcp-get-capability

 [1]
Signed-off-by: default avatarRafael J. Wysocki <rafael.j.wysocki@intel.com>
Link: https://patch.msgid.link/2833494.mvXUDI8C0e@rafael.j.wysocki
parent 93afe8ba

drivers/acpi/acpi_tad.c

+4 −1
Original line number Diff line number Diff line
@@ -706,6 +706,9 @@ static int acpi_tad_probe(struct platform_device *pdev) 
		caps &= ~(ACPI_TAD_AC_WAKE | ACPI_TAD_DC_WAKE);

	}



	if (!(caps & ACPI_TAD_AC_WAKE))

		caps &= ~ACPI_TAD_DC_WAKE;



	dd = devm_kzalloc(dev, sizeof(*dd), GFP_KERNEL);

	if (!dd)

		return -ENOMEM;
@@ -719,7 +722,7 @@ static int acpi_tad_probe(struct platform_device *pdev) 
	 * runtime suspend.  Everything else should be taken care of by the ACPI

	 * PM domain callbacks.

	 */

	if (ACPI_TAD_AC_WAKE | ACPI_TAD_DC_WAKE) {

	if (ACPI_TAD_AC_WAKE) {

		device_init_wakeup(dev, true);

		dev_pm_set_driver_flags(dev, DPM_FLAG_SMART_SUSPEND |

					     DPM_FLAG_MAY_SKIP_RESUME);