[3.13.y.z extended stable] Patch "[media] m88rs2000: prevent frontend crash on continuous transponder scans" has been added to staging queue

Kamal Mostafa kamal at canonical.com
Thu May 1 19:17:07 UTC 2014

This is a note to let you know that I have just added a patch titled

    [media] m88rs2000: prevent frontend crash on continuous transponder scans

to the linux-3.13.y-queue branch of the 3.13.y.z extended stable tree 
which can be found at:


This patch is scheduled to be released in version

If you, or anyone else, feels it should not be added to this tree, please 
reply to this email.

For more information about the 3.13.y.z tree, see



>From 4098867ba3a42440ff74537a20c3175017d91800 Mon Sep 17 00:00:00 2001
From: Malcolm Priestley <tvboxspy at gmail.com>
Date: Tue, 25 Feb 2014 23:11:34 -0300
Subject: [media] m88rs2000: prevent frontend crash on continuous transponder

commit 8272d0a0c0d374a01721e579df6e8add5577132b upstream.

Add m88rs2000_get_tune_settings, min delay of 2000 ms on symbol
rate more than 3000000 and delay of 3000ms less than this.

Adding min delay prevents crashing the frontend on continuous
transponder scans. Other dvb_frontend_tune_settings remain as default.

This makes very little time difference to good channel scans, but slows down
the set frontend where lock can never be achieved i.e. DVB-S2.

Signed-off-by: Malcolm Priestley <tvboxspy at gmail.com>
Signed-off-by: Michael Krufky <mkrufky at linuxtv.org>
Signed-off-by: Mauro Carvalho Chehab <m.chehab at samsung.com>
Signed-off-by: Kamal Mostafa <kamal at canonical.com>
 drivers/media/dvb-frontends/m88rs2000.c | 17 +++++++++++++++++
 1 file changed, 17 insertions(+)

diff --git a/drivers/media/dvb-frontends/m88rs2000.c b/drivers/media/dvb-frontends/m88rs2000.c
index 5b3b1d3..c7a1c8e 100644
--- a/drivers/media/dvb-frontends/m88rs2000.c
+++ b/drivers/media/dvb-frontends/m88rs2000.c
@@ -712,6 +712,22 @@ static int m88rs2000_get_frontend(struct dvb_frontend *fe)
 	return 0;

+static int m88rs2000_get_tune_settings(struct dvb_frontend *fe,
+	struct dvb_frontend_tune_settings *tune)
+	struct dtv_frontend_properties *c = &fe->dtv_property_cache;
+	if (c->symbol_rate > 3000000)
+		tune->min_delay_ms = 2000;
+	else
+		tune->min_delay_ms = 3000;
+	tune->step_size = c->symbol_rate / 16000;
+	tune->max_drift = c->symbol_rate / 2000;
+	return 0;
 static int m88rs2000_i2c_gate_ctrl(struct dvb_frontend *fe, int enable)
 	struct m88rs2000_state *state = fe->demodulator_priv;
@@ -763,6 +779,7 @@ static struct dvb_frontend_ops m88rs2000_ops = {

 	.set_frontend = m88rs2000_set_frontend,
 	.get_frontend = m88rs2000_get_frontend,
+	.get_tune_settings = m88rs2000_get_tune_settings,

 struct dvb_frontend *m88rs2000_attach(const struct m88rs2000_config *config,

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