linux-kernel - [PATCH v4 6/9] gpio: exar: Fix reading of directions and values

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Message-Id: <c0d05abf00776a7f868edf65021c3dcbdd6a3087.1496127684.git.jan.kiszka@siemens.com>
Date:   Tue, 30 May 2017 09:01:21 +0200
From:   Jan Kiszka <jan.kiszka@...mens.com>
To:     Greg Kroah-Hartman <gregkh@...uxfoundation.org>,
        Linus Walleij <linus.walleij@...aro.org>,
        Alexandre Courbot <gnurou@...il.com>
Cc:     Linux Kernel Mailing List <linux-kernel@...r.kernel.org>,
        linux-serial@...r.kernel.org, linux-gpio@...r.kernel.org,
        Sudip Mukherjee <sudip.mukherjee@...ethink.co.uk>,
        Andy Shevchenko <andy.shevchenko@...il.com>,
        Sascha Weisenberger <sascha.weisenberger@...mens.com>
Subject: [PATCH v4 6/9] gpio: exar: Fix reading of directions and values

First, the logic for translating a register bit to the return code of
exar_get_direction and exar_get_value were wrong. And second, there was
a flip regarding the register bank in exar_get_direction.

Signed-off-by: Jan Kiszka <jan.kiszka@...mens.com>
Reviewed-by: Andy Shevchenko <andy.shevchenko@...il.com>
Acked-by: Linus Walleij <linus.walleij@...aro.org>
---
 drivers/gpio/gpio-exar.c | 8 ++++----
 1 file changed, 4 insertions(+), 4 deletions(-)

diff --git a/drivers/gpio/gpio-exar.c b/drivers/gpio/gpio-exar.c
index b29890b143ce..f3585a184f39 100644
--- a/drivers/gpio/gpio-exar.c
+++ b/drivers/gpio/gpio-exar.c
@@ -68,7 +68,7 @@ static int exar_get(struct gpio_chip *chip, unsigned int reg)
 	value = readb(exar_gpio->regs + reg);
 	mutex_unlock(&exar_gpio->lock);
 
-	return !!value;
+	return value;
 }
 
 static int exar_get_direction(struct gpio_chip *chip, unsigned int offset)
@@ -78,7 +78,7 @@ static int exar_get_direction(struct gpio_chip *chip, unsigned int offset)
 	int val;
 
 	addr = bank ? EXAR_OFFSET_MPIOSEL_HI : EXAR_OFFSET_MPIOSEL_LO;
-	val = exar_get(chip, addr) >> (offset % 8);
+	val = exar_get(chip, addr) & BIT(offset % 8);
 
 	return !!val;
 }
@@ -89,8 +89,8 @@ static int exar_get_value(struct gpio_chip *chip, unsigned int offset)
 	unsigned int addr;
 	int val;
 
-	addr = bank ? EXAR_OFFSET_MPIOLVL_LO : EXAR_OFFSET_MPIOLVL_HI;
-	val = exar_get(chip, addr) >> (offset % 8);
+	addr = bank ? EXAR_OFFSET_MPIOLVL_HI : EXAR_OFFSET_MPIOLVL_LO;
+	val = exar_get(chip, addr) & BIT(offset % 8);
 
 	return !!val;
 }
-- 
2.12.3