From f70de486b2dd21b60705e57afecdc5f6a79be4e7 Mon Sep 17 00:00:00 2001
From: Sonic Zhang <sonic.zhang@analog.com>
Date: Mon, 1 Jul 2013 11:24:46 +0800
Subject: [PATCH] Blackfin: bfin_gpio: Use proper mask for comparing pfunc

For BF537_FAMILY, when offset != 1, the mask is 1.
Thus add proper mask for comparing pfunc with function.

Also has small refactor for better readability.
In portmux_setup(), it looks odd having "pmux &= ~(3 << 1);"
while in current code we do pmux |= (function << offset);.

Signed-off-by: Axel Lin <axel.lin@ingics.com>
Signed-off-by: Sonic Zhang <sonic.zhang@analog.com>
---
 arch/blackfin/kernel/bfin_gpio.c | 23 ++++++++++++++---------
 1 file changed, 14 insertions(+), 9 deletions(-)

diff --git a/arch/blackfin/kernel/bfin_gpio.c b/arch/blackfin/kernel/bfin_gpio.c
index ed978f1c5cb9..780d27db1257 100644
--- a/arch/blackfin/kernel/bfin_gpio.c
+++ b/arch/blackfin/kernel/bfin_gpio.c
@@ -255,7 +255,7 @@ static int portmux_group_check(unsigned short per)
 	u16 ident = P_IDENT(per);
 	u16 function = P_FUNCT2MUX(per);
 	s8 offset = port_mux[ident];
-	u16 m, pmux, pfunc;
+	u16 m, pmux, pfunc, mask;
 
 	if (offset < 0)
 		return 0;
@@ -270,10 +270,12 @@ static int portmux_group_check(unsigned short per)
 			continue;
 
 		if (offset == 1)
-			pfunc = (pmux >> offset) & 3;
+			mask = 3;
 		else
-			pfunc = (pmux >> offset) & 1;
-		if (pfunc != function) {
+			mask = 1;
+
+		pfunc = (pmux >> offset) & mask;
+		if (pfunc != (function & mask)) {
 			pr_err("pin group conflict! request pin %d func %d conflict with pin %d func %d\n",
 				ident, function, m, pfunc);
 			return -EINVAL;
@@ -288,17 +290,20 @@ static void portmux_setup(unsigned short per)
 	u16 ident = P_IDENT(per);
 	u16 function = P_FUNCT2MUX(per);
 	s8 offset = port_mux[ident];
-	u16 pmux;
+	u16 pmux, mask;
 
 	if (offset == -1)
 		return;
 
 	pmux = bfin_read_PORT_MUX();
-	if (offset != 1)
-		pmux &= ~(1 << offset);
+	if (offset == 1)
+		mask = 3;
 	else
-		pmux &= ~(3 << 1);
-	pmux |= (function << offset);
+		mask = 1;
+
+	pmux &= ~(mask << offset);
+	pmux |= ((function & mask) << offset);
+
 	bfin_write_PORT_MUX(pmux);
 }
 #elif defined(CONFIG_BF54x) || defined(CONFIG_BF60x)
-- 
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