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From:   Wayne Chang <waynec@nvidia.com>
To:     <heikki.krogerus@linux.intel.com>, <gregkh@linuxfoundation.org>
CC:     <singhanc@nvidia.com>, <waynec@nvidia.com>,
        <linux-usb@vger.kernel.org>, <linux-kernel@vger.kernel.org>
Subject: [PATCH 1/1] ucsi_ccg: Check DEV_INT bit only when starting CCG4
Date:   Fri, 7 Jan 2022 17:24:55 +0800
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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: WayneChang <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