linux-kernel - [PATCH v2 4/6] gpio: exar: Fix reading of directions and values

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Message-Id: <ace08e630ab57d08817c5e8669094c10a7c667ad.1495119548.git.jan.kiszka@siemens.com>
Date:   Thu, 18 May 2017 16:59:07 +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 v2 4/6] 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>
---
 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 4ed1f8bdeda7..d8b6296c11de 100644
--- a/drivers/gpio/gpio-exar.c
+++ b/drivers/gpio/gpio-exar.c
@@ -69,7 +69,7 @@ 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)
@@ -79,7 +79,7 @@ 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;
 }
@@ -90,8 +90,8 @@ 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;
 }
-- 
2.12.0