[3.11.y.z extended stable] Patch "[media] fc2580: fix tuning failure on 32-bit arch" has been added to staging queue

[Luis Henriques]

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

    [media] fc2580: fix tuning failure on 32-bit arch

to the linux-3.11.y-queue branch of the 3.11.y.z extended stable tree 
which can be found at:

 http://kernel.ubuntu.com/git?p=ubuntu/linux.git;a=shortlog;h=refs/heads/linux-3.11.y-queue

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

For more information about the 3.11.y.z tree, see
https://wiki.ubuntu.com/Kernel/Dev/ExtendedStable

Thanks.
-Luis

------

>From f6c01888606200e850cdb622ac1433cdb638e034 Mon Sep 17 00:00:00 2001
From: Antti Palosaari <crope at iki.fi>
Date: Thu, 10 Apr 2014 21:18:16 -0300
Subject: [media] fc2580: fix tuning failure on 32-bit arch

commit 8845cc6415ec28ef8d57b3fb81c75ef9bce69c5f upstream.

There was some frequency calculation overflows which caused tuning
failure on 32-bit architecture. Use 64-bit numbers where needed in
order to avoid calculation overflows.

Thanks for the Finnish person, who asked remain anonymous, reporting,
testing and suggesting the fix.

Signed-off-by: Antti Palosaari <crope at iki.fi>
Signed-off-by: Mauro Carvalho Chehab <m.chehab at samsung.com>
Signed-off-by: Luis Henriques <luis.henriques at canonical.com>
---
 drivers/media/tuners/fc2580.c      | 6 +++---
 drivers/media/tuners/fc2580_priv.h | 1 +
 2 files changed, 4 insertions(+), 3 deletions(-)

diff --git a/drivers/media/tuners/fc2580.c b/drivers/media/tuners/fc2580.c
index 3aecaf465094..f0c9c42867de 100644
--- a/drivers/media/tuners/fc2580.c
+++ b/drivers/media/tuners/fc2580.c
@@ -195,7 +195,7 @@ static int fc2580_set_params(struct dvb_frontend *fe)

 	f_ref = 2UL * priv->cfg->clock / r_val;
 	n_val = div_u64_rem(f_vco, f_ref, &k_val);
-	k_val_reg = 1UL * k_val * (1 << 20) / f_ref;
+	k_val_reg = div_u64(1ULL * k_val * (1 << 20), f_ref);

 	ret = fc2580_wr_reg(priv, 0x18, r18_val | ((k_val_reg >> 16) & 0xff));
 	if (ret < 0)
@@ -348,8 +348,8 @@ static int fc2580_set_params(struct dvb_frontend *fe)
 	if (ret < 0)
 		goto err;

-	ret = fc2580_wr_reg(priv, 0x37, 1UL * priv->cfg->clock * \
-			fc2580_if_filter_lut[i].mul / 1000000000);
+	ret = fc2580_wr_reg(priv, 0x37, div_u64(1ULL * priv->cfg->clock *
+			fc2580_if_filter_lut[i].mul, 1000000000));
 	if (ret < 0)
 		goto err;

diff --git a/drivers/media/tuners/fc2580_priv.h b/drivers/media/tuners/fc2580_priv.h
index be38a9e637e0..646c99452136 100644
--- a/drivers/media/tuners/fc2580_priv.h
+++ b/drivers/media/tuners/fc2580_priv.h
@@ -22,6 +22,7 @@
 #define FC2580_PRIV_H

 #include "fc2580.h"
+#include <linux/math64.h>

 struct fc2580_reg_val {
 	u8 reg;
--
1.9.1