mwifiex: pcie: add reset_wsid quirk for Surface 3

This commit adds reset_wsid quirk and uses this quirk for Surface 3 on
card reset.

To reset mwifiex on Surface 3, it seems that calling the _DSM method
exists in \_SB.WSID [1] device is required.

On Surface 3, calling the _DSM method removes/re-probes the card by
itself. So, need to place the reset function before performing FLR and
skip performing any other reset-related works.

Note that Surface Pro 3 also has the WSID device [2], but it seems to need
more work. This commit only supports Surface 3 yet.

[1] https://github.com/linux-surface/acpidumps/blob/05cba925f3a515f222acb5b3551a032ddde958fe/surface_3/dsdt.dsl#L11947-L12011
[2] https://github.com/linux-surface/acpidumps/blob/05cba925f3a515f222acb5b3551a032ddde958fe/surface_pro_3/dsdt.dsl#L12164-L12216

Signed-off-by: Tsuchiya Yuto <kitakar@gmail.com>
Patchset: mwifiex

drivers/net/wireless/marvell/mwifiex/pcie.c

@@ -2981,6 +2981,16 @@ static void mwifiex_pcie_card_reset_work(struct mwifiex_adapter *adapter)
 {
 	struct pcie_service_card *card = adapter->card;
 
+	/* On Surface 3, reset_wsid method removes then re-probes card by
+	 * itself. So, need to place it here and skip performing any other
+	 * reset-related works.
+	 */
+	if (card->quirks & QUIRK_FW_RST_WSID_S3) {
+		mwifiex_pcie_reset_wsid_quirk(card->dev);
+		/* skip performing any other reset-related works */
+		return;
+	}
+
 	/* We can't afford to wait here; remove() might be waiting on us. If we
 	 * can't grab the device lock, maybe we'll get another chance later.
 	 */

drivers/net/wireless/marvell/mwifiex/pcie_quirks.c

@@ -1,10 +1,21 @@
 // SPDX-License-Identifier: GPL-2.0-only
 // NXP Wireless LAN device driver: PCIE and platform specific quirks
 
+#include <linux/acpi.h>
 #include <linux/dmi.h>
 
 #include "pcie_quirks.h"
 
+/* For reset_wsid quirk */
+#define ACPI_WSID_PATH		"\\_SB.WSID"
+#define WSID_REV		0x0
+#define WSID_FUNC_WIFI_PWR_OFF	0x1
+#define WSID_FUNC_WIFI_PWR_ON	0x2
+/* WSID _DSM UUID: "534ea3bf-fcc2-4e7a-908f-a13978f0c7ef" */
+static const guid_t wsid_dsm_guid =
+	GUID_INIT(0x534ea3bf, 0xfcc2, 0x4e7a,
+		  0x90, 0x8f, 0xa1, 0x39, 0x78, 0xf0, 0xc7, 0xef);
+
 /* quirk table based on DMI matching */
 static const struct dmi_system_id mwifiex_quirk_table[] = {
 	{
@@ -73,6 +84,14 @@ static const struct dmi_system_id mwifiex_quirk_table[] = {
 		},
 		.driver_data = (void *)QUIRK_FW_RST_D3COLD,
 	},
+	{
+		.ident = "Surface 3",
+		.matches = {
+			DMI_EXACT_MATCH(DMI_SYS_VENDOR, "Microsoft Corporation"),
+			DMI_EXACT_MATCH(DMI_PRODUCT_NAME, "Surface 3"),
+		},
+		.driver_data = (void *)QUIRK_FW_RST_WSID_S3,
+	},
 	{}
 };
 
@@ -89,6 +108,9 @@ void mwifiex_initialize_quirks(struct pcie_service_card *card)
 		dev_info(&pdev->dev, "no quirks enabled\n");
 	if (card->quirks & QUIRK_FW_RST_D3COLD)
 		dev_info(&pdev->dev, "quirk reset_d3cold enabled\n");
+	if (card->quirks & QUIRK_FW_RST_WSID_S3)
+		dev_info(&pdev->dev,
+			 "quirk reset_wsid for Surface 3 enabled\n");
 }
 
 static void mwifiex_pcie_set_power_d3cold(struct pci_dev *pdev)
@@ -145,3 +167,64 @@ int mwifiex_pcie_reset_d3cold_quirk(struct pci_dev *pdev)
 
 	return 0;
 }
+
+int mwifiex_pcie_reset_wsid_quirk(struct pci_dev *pdev)
+{
+	acpi_handle handle;
+	union acpi_object *obj;
+	acpi_status status;
+
+	dev_info(&pdev->dev, "Using reset_wsid quirk to perform FW reset\n");
+
+	status = acpi_get_handle(NULL, ACPI_WSID_PATH, &handle);
+	if (ACPI_FAILURE(status)) {
+		dev_err(&pdev->dev, "No ACPI handle for path %s\n",
+			ACPI_WSID_PATH);
+		return -ENODEV;
+	}
+
+	if (!acpi_has_method(handle, "_DSM")) {
+		dev_err(&pdev->dev, "_DSM method not found\n");
+		return -ENODEV;
+	}
+
+	if (!acpi_check_dsm(handle, &wsid_dsm_guid,
+			    WSID_REV, WSID_FUNC_WIFI_PWR_OFF)) {
+		dev_err(&pdev->dev,
+			"_DSM method doesn't support wifi power off func\n");
+		return -ENODEV;
+	}
+
+	if (!acpi_check_dsm(handle, &wsid_dsm_guid,
+			    WSID_REV, WSID_FUNC_WIFI_PWR_ON)) {
+		dev_err(&pdev->dev,
+			"_DSM method doesn't support wifi power on func\n");
+		return -ENODEV;
+	}
+
+	/* card will be removed immediately after this call on Surface 3 */
+	dev_info(&pdev->dev, "turning wifi off...\n");
+	obj = acpi_evaluate_dsm(handle, &wsid_dsm_guid,
+				WSID_REV, WSID_FUNC_WIFI_PWR_OFF,
+				NULL);
+	if (!obj) {
+		dev_err(&pdev->dev,
+			"device _DSM execution failed for turning wifi off\n");
+		return -EIO;
+	}
+	ACPI_FREE(obj);
+
+	/* card will be re-probed immediately after this call on Surface 3 */
+	dev_info(&pdev->dev, "turning wifi on...\n");
+	obj = acpi_evaluate_dsm(handle, &wsid_dsm_guid,
+				WSID_REV, WSID_FUNC_WIFI_PWR_ON,
+				NULL);
+	if (!obj) {
+		dev_err(&pdev->dev,
+			"device _DSM execution failed for turning wifi on\n");
+		return -EIO;
+	}
+	ACPI_FREE(obj);
+
+	return 0;
+}

drivers/net/wireless/marvell/mwifiex/pcie_quirks.h

@@ -5,5 +5,11 @@
 
 #define QUIRK_FW_RST_D3COLD	BIT(0)
 
+/* Surface 3 and Surface Pro 3 have the same _DSM method but need to
+ * be handled differently. Currently, only S3 is supported.
+ */
+#define QUIRK_FW_RST_WSID_S3	BIT(1)
+
 void mwifiex_initialize_quirks(struct pcie_service_card *card);
 int mwifiex_pcie_reset_d3cold_quirk(struct pci_dev *pdev);
+int mwifiex_pcie_reset_wsid_quirk(struct pci_dev *pdev);