From 825911492eb15bf8bb7fb94bc0c0421fe7a6327d Mon Sep 17 00:00:00 2001
From: Sing-Han Chen <singhanc@nvidia.com>
Date: Wed, 12 Jan 2022 17:41:43 +0800
Subject: [PATCH] ucsi_ccg: Check DEV_INT bit only when starting CCG4
Git-commit: 825911492eb15bf8bb7fb94bc0c0421fe7a6327d
Patch-mainline: v5.17-rc2
References: git-fixes
CCGx clears Bit 0:Device Interrupt in the INTR_REG
if CCGx is reset successfully. However, there might
be a chance that other bits in INTR_REG are not
cleared due to internal data queued in PPM. This case
misleads the driver that CCGx reset failed.
The commit checks bit 0 in INTR_REG and ignores other
bits. The ucsi driver would reset PPM later.
Fixes: 247c554a14aa ("usb: typec: ucsi: add support for Cypress CCGx")
Cc: stable@vger.kernel.org
Reviewed-by: Heikki Krogerus <heikki.krogerus@linux.intel.com>
Signed-off-by: Sing-Han Chen <singhanc@nvidia.com>
Signed-off-by: Wayne Chang <waynec@nvidia.com>
Link: https://lore.kernel.org/r/20220112094143.628610-1-waynec@nvidia.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Acked-by: Takashi Iwai <tiwai@suse.de>
---
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));
--
2.31.1