Received-SPF: Pass (protection.outlook.com: domain of nvidia.com designates
 12.22.5.235 as permitted sender) receiver=protection.outlook.com;
 client-ip=12.22.5.235; helo=mail.nvidia.com;
From:   Wayne Chang <waynec@nvidia.com>
To:     <heikki.krogerus@linux.intel.com>, <gregkh@linuxfoundation.org>
CC:     <linux-kernel@vger.kernel.org>, <linux-usb@vger.kernel.org>,
        <singhanc@nvidia.com>, <waynec@nvidia.com>
Subject: [PATCH v2 1/1] ucsi_ccg: Check DEV_INT bit only when starting CCG4
Date:   Tue, 11 Jan 2022 21:36:43 +0800
Message-ID: <20220111133643.589346-1-waynec@nvidia.com>
MIME-Version: 1.0
Content-Transfer-Encoding: 8bit
Content-Type: text/plain
X-MS-Exchange-CrossTenant-OriginalArrivalTime: 11 Jan 2022 13:36:47.5164
 (UTC)
X-MS-Exchange-CrossTenant-Network-Message-Id: 44206838-589a-45dc-fe1c-08d9d5076a66
X-MS-Exchange-CrossTenant-Id: 43083d15-7273-40c1-b7db-39efd9ccc17a
X-MS-Exchange-CrossTenant-OriginalAttributedTenantConnectingIp: TenantId=43083d15-7273-40c1-b7db-39efd9ccc17a;Ip=[12.22.5.235];Helo=[mail.nvidia.com]
X-MS-Exchange-CrossTenant-AuthSource: CO1NAM11FT055.eop-nam11.prod.protection.outlook.com
X-MS-Exchange-CrossTenant-AuthAs: Anonymous
X-MS-Exchange-CrossTenant-FromEntityHeader: HybridOnPrem
X-MS-Exchange-Transport-CrossTenantHeadersStamped: MWHPR12MB1486
Precedence: bulk
List-ID: <linux-kernel.vger.kernel.org>
X-Mailing-List: linux-kernel@vger.kernel.org

From: Sing-Han Chen <singhanc@nvidia.com>

after driver sending the UCSI_START cmd, CCGx would
clear Bit 0:Device Interrupt in the INTR_REG if CCGX
reset successfully.

however, there might be a chance that other bits in
INTR_REG are not cleared due to internal data queued
in PPM and cause the driver thinks CCGx reset failed.

the commit checks bit 0 in INTR_REG and ignore other
bits. ucsi driver would reset PPM later.

Signed-off-by: Sing-Han Chen <singhanc@nvidia.com>
Signed-off-by: Wayne Chang <waynec@nvidia.com>
---
 drivers/usb/typec/ucsi/ucsi_ccg.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/usb/typec/ucsi/ucsi_ccg.c b/drivers/usb/typec/ucsi/ucsi_ccg.c
index bff96d64dddf..6db7c8ddd51c 100644
--- a/drivers/usb/typec/ucsi/ucsi_ccg.c
+++ b/drivers/usb/typec/ucsi/ucsi_ccg.c
@@ -325,7 +325,7 @@ static int ucsi_ccg_init(struct ucsi_ccg *uc)
 		if (status < 0)
 			return status;
 
-		if (!data)
+		if (!(data & DEV_INT))
 			return 0;
 
 		status = ccg_write(uc, CCGX_RAB_INTR_REG, &data, sizeof(data));
-- 
2.25.1