From 7e06e0d5493b3e88016b247fe92f67a071d2c655 Mon Sep 17 00:00:00 2001
From: Hong Liu <hong.liu@intel.com>
Date: Tue, 12 Feb 2019 20:05:22 +0800
Subject: [PATCH] HID: intel-ish-hid: move doorbell writing before flush
Git-commit: 7e06e0d5493b3e88016b247fe92f67a071d2c655
Patch-mainline: v5.1-rc1
References: jsc#SLE-5241

Reading of IPC_REG_ISH_HOST_FWSTS will flush both message register
and doorbell. So move the doorbell write before reading of
IPC_REG_ISH_HOST_FWSTS.

Signed-off-by: Hong Liu <hong.liu@intel.com>
Tested-by: Hongyan Song <hongyan.song@intel.com>
Acked-by: Srinivas Pandruvada <srinivas.pandruvada@linux.intel.com>
Signed-off-by: Jiri Kosina <jkosina@suse.cz>
Acked-by: Takashi Iwai <tiwai@suse.de>

---
 drivers/hid/intel-ish-hid/ipc/ipc.c | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/drivers/hid/intel-ish-hid/ipc/ipc.c b/drivers/hid/intel-ish-hid/ipc/ipc.c
index ff8eca11ff73..30d8a639a5bb 100644
--- a/drivers/hid/intel-ish-hid/ipc/ipc.c
+++ b/drivers/hid/intel-ish-hid/ipc/ipc.c
@@ -314,6 +314,8 @@ static int write_ipc_from_queue(struct ishtp_device *dev)
 		memcpy(&reg, &r_buf[length >> 2], rem);
 		ish_reg_write(dev, reg_addr, reg);
 	}
+	ish_reg_write(dev, IPC_REG_HOST2ISH_DRBL, doorbell_val);
+
 	/* Flush writes to msg registers and doorbell */
 	ish_reg_read(dev, IPC_REG_ISH_HOST_FWSTS);
 
@@ -321,8 +323,6 @@ static int write_ipc_from_queue(struct ishtp_device *dev)
 	++dev->ipc_tx_cnt;
 	dev->ipc_tx_bytes_cnt += IPC_HEADER_GET_LENGTH(doorbell_val);
 
-	ish_reg_write(dev, IPC_REG_HOST2ISH_DRBL, doorbell_val);
-
 	ipc_send_compl = ipc_link->ipc_send_compl;
 	ipc_send_compl_prm = ipc_link->ipc_send_compl_prm;
 	list_del_init(&ipc_link->link);
-- 
2.16.4