Commit d9239fdc authored by Rafael J. Wysocki's avatar Rafael J. Wysocki
Browse files

ACPI: bus: Rework the handling of \_SB._OSC USB4 features 



Use acpi_osc_handshake() introduced previously for implementing the
\_SB._OSC USB4 features control negotiation.

Signed-off-by: default avatarRafael J. Wysocki <rafael.j.wysocki@intel.com>
Reviewed-by: default avatarJonathan Cameron <jonathan.cameron@huawei.com>
Link: https://patch.msgid.link/3879947.MHq7AAxBmi@rafael.j.wysocki
parent 64850593

drivers/acpi/bus.c

+8 −50
Original line number Diff line number Diff line
@@ -528,19 +528,15 @@ static void acpi_bus_decode_usb_osc(const char *msg, u32 bits) 
	       (bits & OSC_USB_XDOMAIN) ? '+' : '-');

}



static u8 sb_usb_uuid_str[] = "23A0D13A-26AB-486C-9C5F-0FFA525A575A";

static void acpi_bus_osc_negotiate_usb_control(void)

{

	u32 capbuf[3], *capbuf_ret;

	struct acpi_osc_context context = {

		.uuid_str = sb_usb_uuid_str,

		.rev = 1,

		.cap.length = sizeof(capbuf),

		.cap.pointer = capbuf,

	static const u8 sb_usb_uuid_str[] = "23A0D13A-26AB-486C-9C5F-0FFA525A575A";

	u32 capbuf[3], control;

	struct acpi_buffer cap = {

		.pointer = capbuf,

		.length = sizeof(capbuf),

	};

	acpi_handle handle;

	acpi_status status;

	u32 control;



	if (!osc_sb_native_usb4_support_confirmed)

		return;
@@ -551,54 +547,16 @@ static void acpi_bus_osc_negotiate_usb_control(void) 
	control = OSC_USB_USB3_TUNNELING | OSC_USB_DP_TUNNELING |

		  OSC_USB_PCIE_TUNNELING | OSC_USB_XDOMAIN;



	/*

	 * Run _OSC first with query bit set, trying to get control over

	 * all tunneling. The platform can then clear out bits in the

	 * control dword that it does not want to grant to the OS.

	 */

	capbuf[OSC_QUERY_DWORD] = OSC_QUERY_ENABLE;

	capbuf[OSC_SUPPORT_DWORD] = 0;

	capbuf[OSC_CONTROL_DWORD] = control;



	status = acpi_run_osc(handle, &context);

	if (ACPI_FAILURE(status))

		return;



	if (context.ret.length != sizeof(capbuf)) {

		pr_info("USB4 _OSC: returned invalid length buffer\n");

		goto out_free;

	}



	/*

	 * Run _OSC again now with query bit clear and the control dword

	 * matching what the platform granted (which may not have all

	 * the control bits set).

	 */

	capbuf_ret = context.ret.pointer;



	capbuf[OSC_QUERY_DWORD] = 0;

	capbuf[OSC_CONTROL_DWORD] = capbuf_ret[OSC_CONTROL_DWORD];



	kfree(context.ret.pointer);



	status = acpi_run_osc(handle, &context);

	if (ACPI_FAILURE(status))

	if (acpi_osc_handshake(handle, sb_usb_uuid_str, 1, &cap))

		return;



	if (context.ret.length != sizeof(capbuf)) {

		pr_info("USB4 _OSC: returned invalid length buffer\n");

		goto out_free;

	}



	osc_sb_native_usb4_control =

		control & acpi_osc_ctx_get_pci_control(&context);

	osc_sb_native_usb4_control = capbuf[OSC_CONTROL_DWORD];



	acpi_bus_decode_usb_osc("USB4 _OSC: OS supports", control);

	acpi_bus_decode_usb_osc("USB4 _OSC: OS controls",

				osc_sb_native_usb4_control);



out_free:

	kfree(context.ret.pointer);

	acpi_bus_decode_usb_osc("USB4 _OSC: OS controls", osc_sb_native_usb4_control);

}



/* --------------------------------------------------------------------------