[PATCH 4.15 21/84] media: [RESEND] media: dvb-frontends: Add delay to Si2168 restart

[Greg Kroah-Hartman]

4.15-stable review patch.  If anyone has any objections, please let me know.

------------------

From: Ron Economos <w6rz@xxxxxxxxxxx>


[ Upstream commit 380a6c86457573aa42d27ae11e025eb25941a0b7 ]

On faster CPUs a delay is required after the resume command and the restart command. Without the delay, the restart command often returns -EREMOTEIO and the Si2168 does not restart.

Note that this patch fixes the same issue as https://patchwork.linuxtv.org/patch/44304/, but I believe my udelay() fix addresses the actual problem.

Signed-off-by: Ron Economos <w6rz@xxxxxxxxxxx>
Signed-off-by: Mauro Carvalho Chehab <mchehab@xxxxxxxxxxxxxxxx>
Signed-off-by: Sasha Levin <alexander.levin@xxxxxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
---
 drivers/media/dvb-frontends/si2168.c |    3 +++
 1 file changed, 3 insertions(+)

--- a/drivers/media/dvb-frontends/si2168.c
+++ b/drivers/media/dvb-frontends/si2168.c
@@ -14,6 +14,8 @@
  *    GNU General Public License for more details.
  */
 
+#include <linux/delay.h>
+
 #include "si2168_priv.h"
 
 static const struct dvb_frontend_ops si2168_ops;
@@ -435,6 +437,7 @@ static int si2168_init(struct dvb_fronte
 		if (ret)
 			goto err;
 
+		udelay(100);
 		memcpy(cmd.args, "\x85", 1);
 		cmd.wlen = 1;
 		cmd.rlen = 1;