This is a note to let you know that I've just added the patch titled Bluetooth: btbcm: disable read tx power for some Macs with the T2 Security chip to the 5.15-stable tree which can be found at: http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary The filename of the patch is: bluetooth-btbcm-disable-read-tx-power-for-some-macs-with-the-t2-security-chip.patch and it can be found in the queue-5.15 subdirectory. If you, or anyone else, feels it should not be added to the stable tree, please let <stable@xxxxxxxxxxxxxxx> know about it. >From 801b4c027b44a185292007d3cf7513999d644723 Mon Sep 17 00:00:00 2001 From: Aditya Garg <gargaditya08@xxxxxxxx> Date: Thu, 2 Dec 2021 12:42:59 +0000 Subject: Bluetooth: btbcm: disable read tx power for some Macs with the T2 Security chip From: Aditya Garg <gargaditya08@xxxxxxxx> commit 801b4c027b44a185292007d3cf7513999d644723 upstream. 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 <gargaditya08@xxxxxxxx> Reported-by: Orlando Chamberlain <redecorating@xxxxxxxxxxxxxx> Tested-by: Orlando Chamberlain <redecorating@xxxxxxxxxxxxxx> Link: https://lore.kernel.org/r/4970a940-211b-25d6-edab-21a815313954@xxxxxxxxxxxxxx Fixes: 7c395ea521e6 ("Bluetooth: Query LE tx power on startup") Cc: stable@xxxxxxxxxxxxxxx Signed-off-by: Marcel Holtmann <marcel@xxxxxxxxxxxx> Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx> --- drivers/bluetooth/btbcm.c | 39 +++++++++++++++++++++++++++++++++++++++ 1 file changed, 39 insertions(+) --- a/drivers/bluetooth/btbcm.c +++ b/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_pr 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_de 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; } Patches currently in stable-queue which might be from gargaditya08@xxxxxxxx are queue-5.15/bluetooth-add-quirk-disabling-le-read-transmit-power.patch queue-5.15/bluetooth-btbcm-disable-read-tx-power-for-macbook-air-8-1-and-8-2.patch queue-5.15/mfd-intel-lpss-fix-too-early-pm-enablement-in-the-acpi-probe.patch queue-5.15/bluetooth-btbcm-disable-read-tx-power-for-some-macs-with-the-t2-security-chip.patch