From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-1.web.codeaurora.org [10.30.226.201]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id C7C2E341050 for ; Sat, 28 Feb 2026 17:51:57 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=10.30.226.201 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1772301117; cv=none; b=KV/70/gUcQVtF/5E6XdbhLqMosnYGDkrl7MHPtAPNEu4t8W1B+h86ekWA4O4U9tEmy2HxbhsIW5ONOj7OUoijNHnv9sHmPaFCjjEoEpjp9GyY66lHQ3+KAiZWDZzf2PE3Ypuv5kWGLObEOMRMBOxQwSGVkVOR6d+dfsYm6g8+vA= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1772301117; c=relaxed/simple; bh=5JgT2L3Zry9ZaKOHywsRUBM87mU0XvTZ6LuSRBXw7Wo=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=l6tD9R3WbUsHGJB4+sy70DN3zvhRZlgzkcGvSu4AJ9vQE5sN+kA1blZMTt9BV77mp/Xr6H/hbkaGf2kN5MO0AMxNFC/uDDsC7G5iQPZvxh1xpcrgTGXKPObbVWJOmC8SBetCyFQ4uSuOmawHKcR2eIhLD0nRWA65GNGyDs/pDKA= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=uO3HRD33; arc=none smtp.client-ip=10.30.226.201 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b="uO3HRD33" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 24172C19423; Sat, 28 Feb 2026 17:51:57 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1772301117; bh=5JgT2L3Zry9ZaKOHywsRUBM87mU0XvTZ6LuSRBXw7Wo=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=uO3HRD33JO4SxlFdqNQHN3fLiTOmupRBQE/p5RD/Sts41H+Vnu9ESEtK1PY3A58HU qGH+kX9CmWdDr63AaL1vqZ6SBo8T0F8LxY/NUxIQNr8T7aMbgI2c6rmk8iduPiuaAO PwkpxETfcEC/5FLtLBE5nbgaJdHQcNshzMQ+PXBSXoechXbV5LDN+6wsedHFSp8UGk A21CS5W3xxB0GBgDNX6fWi34Hpd37zud/D1UNVP88prLbxafnktf1h9VO6Gs1t1afY cE1dnSx+wbU3nLHhezB9g4mq2KEc4ZKrKFDXfjYrmNh/rQQdy8N99rSpof0PHHdxpC HuWt4J01ZsETg== From: Sasha Levin To: patches@lists.linux.dev Cc: Shuai Zhang , Dmitry Baryshkov , Luiz Augusto von Dentz , Sasha Levin Subject: [PATCH 6.18 274/752] Bluetooth: hci_qca: Fix SSR (SubSystem Restart) fail when BT_EN is pulled up by hw Date: Sat, 28 Feb 2026 12:39:45 -0500 Message-ID: <20260228174750.1542406-274-sashal@kernel.org> X-Mailer: git-send-email 2.51.0 In-Reply-To: <20260228174750.1542406-1-sashal@kernel.org> References: <20260228174750.1542406-1-sashal@kernel.org> Precedence: bulk X-Mailing-List: patches@lists.linux.dev List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 X-stable: review X-Patchwork-Hint: Ignore Content-Transfer-Encoding: 8bit From: Shuai Zhang [ Upstream commit fce1a9244a0f85683be8530e623bc729f24c5067 ] On QCS9075 and QCA8275 platforms, the BT_EN pin is always pulled up by hw and cannot be controlled by the host. As a result, in case of a firmware crash, the host cannot trigger a cold reset. Instead, the BT controller performs a warm restart on its own, without reloading the firmware. This leads to the controller remaining in IBS_WAKE state, while the host expects it to be in sleep mode. The mismatch causes HCI reset commands to time out. Additionally, the driver does not clear internal flags QCA_SSR_TRIGGERED and QCA_IBS_DISABLED, which blocks the reset sequence. If the SSR duration exceeds 2 seconds, the host may enter TX sleep mode due to tx_idle_timeout, further preventing recovery. Also, memcoredump_flag is not cleared, so only the first SSR generates a coredump. Tell the driver that the BT controller has undergone a proper restart sequence: - Clear QCA_SSR_TRIGGERED and QCA_IBS_DISABLED flags after SSR. - Add a 50ms delay to allow the controller to complete its warm reset. - Reset tx_idle_timer to prevent the host from entering TX sleep mode. - Clear memcoredump_flag to allow multiple coredump captures. Apply these steps only when HCI_QUIRK_NON_PERSISTENT_SETUP is not set, which indicates that BT_EN is defined in DTS and cannot be toggled. Refer to the comment in include/net/bluetooth/hci.h for details on HCI_QUIRK_NON_PERSISTENT_SETUP. Reviewed-by: Dmitry Baryshkov Signed-off-by: Shuai Zhang Signed-off-by: Luiz Augusto von Dentz Signed-off-by: Sasha Levin --- drivers/bluetooth/hci_qca.c | 33 +++++++++++++++++++++++++++++++++ 1 file changed, 33 insertions(+) diff --git a/drivers/bluetooth/hci_qca.c b/drivers/bluetooth/hci_qca.c index 888176b0faa90..a3c217571c3c4 100644 --- a/drivers/bluetooth/hci_qca.c +++ b/drivers/bluetooth/hci_qca.c @@ -1653,6 +1653,39 @@ static void qca_hw_error(struct hci_dev *hdev, u8 code) skb_queue_purge(&qca->rx_memdump_q); } + /* + * If the BT chip's bt_en pin is connected to a 3.3V power supply via + * hardware and always stays high, driver cannot control the bt_en pin. + * As a result, during SSR (SubSystem Restart), QCA_SSR_TRIGGERED and + * QCA_IBS_DISABLED flags cannot be cleared, which leads to a reset + * command timeout. + * Add an msleep delay to ensure controller completes the SSR process. + * + * Host will not download the firmware after SSR, controller to remain + * in the IBS_WAKE state, and the host needs to synchronize with it + * + * Since the bluetooth chip has been reset, clear the memdump state. + */ + if (!hci_test_quirk(hu->hdev, HCI_QUIRK_NON_PERSISTENT_SETUP)) { + /* + * When the SSR (SubSystem Restart) duration exceeds 2 seconds, + * it triggers host tx_idle_delay, which sets host TX state + * to sleep. Reset tx_idle_timer after SSR to prevent + * host enter TX IBS_Sleep mode. + */ + mod_timer(&qca->tx_idle_timer, jiffies + + msecs_to_jiffies(qca->tx_idle_delay)); + + /* Controller reset completion time is 50ms */ + msleep(50); + + clear_bit(QCA_SSR_TRIGGERED, &qca->flags); + clear_bit(QCA_IBS_DISABLED, &qca->flags); + + qca->tx_ibs_state = HCI_IBS_TX_AWAKE; + qca->memdump_state = QCA_MEMDUMP_IDLE; + } + clear_bit(QCA_HW_ERROR_EVENT, &qca->flags); } -- 2.51.0