Bluetooth: btbcm: disable read tx power for some Macs with the T2 Security chip

Some Macs with the T2 security chip had Bluetooth not working.
To fix it we add DMI based quirks to disable querying of LE Tx power.

Signed-off-by: Aditya Garg <[email protected]>
Reported-by: Orlando Chamberlain <[email protected]>
Tested-by: Orlando Chamberlain <[email protected]>
Link:
https://lore.kernel.org/r/[email protected]
Fixes: 7c395ea ("Bluetooth: Query LE tx power on startup")
Cc: [email protected]
Signed-off-by: Marcel Holtmann <[email protected]>

Author: AdityaGarg8

drivers/bluetooth/btbcm.c

@@ -8,6 +8,7 @@
 
 #include <linux/module.h>
 #include <linux/firmware.h>
+#include <linux/dmi.h>
 #include <asm/unaligned.h>
 
 #include <net/bluetooth/bluetooth.h>
@@ -343,6 +344,40 @@ static struct sk_buff *btbcm_read_usb_product(struct hci_dev *hdev)
 	return skb;
 }
 
+static const struct dmi_system_id disable_broken_read_transmit_power[] = {
+	{
+		 .matches = {
+			DMI_MATCH(DMI_BOARD_VENDOR, "Apple Inc."),
+			DMI_MATCH(DMI_PRODUCT_NAME, "MacBookPro16,1"),
+		},
+	},
+	{
+		 .matches = {
+			DMI_MATCH(DMI_BOARD_VENDOR, "Apple Inc."),
+			DMI_MATCH(DMI_PRODUCT_NAME, "MacBookPro16,2"),
+		},
+	},
+	{
+		 .matches = {
+			DMI_MATCH(DMI_BOARD_VENDOR, "Apple Inc."),
+			DMI_MATCH(DMI_PRODUCT_NAME, "MacBookPro16,4"),
+		},
+	},
+	{
+		 .matches = {
+			DMI_MATCH(DMI_BOARD_VENDOR, "Apple Inc."),
+			DMI_MATCH(DMI_PRODUCT_NAME, "iMac20,1"),
+		},
+	},
+	{
+		 .matches = {
+			DMI_MATCH(DMI_BOARD_VENDOR, "Apple Inc."),
+			DMI_MATCH(DMI_PRODUCT_NAME, "iMac20,2"),
+		},
+	},
+	{ }
+};
+
 static int btbcm_read_info(struct hci_dev *hdev)
 {
 	struct sk_buff *skb;
@@ -363,6 +398,10 @@ static int btbcm_read_info(struct hci_dev *hdev)
 	bt_dev_info(hdev, "BCM: features 0x%2.2x", skb->data[1]);
 	kfree_skb(skb);
 
+	/* Read DMI and disable broken Read LE Min/Max Tx Power */
+	if (dmi_first_match(disable_broken_read_transmit_power))
+		set_bit(HCI_QUIRK_BROKEN_READ_TRANSMIT_POWER, &hdev->quirks);
+
 	return 0;
 }