From mboxrd@z Thu Jan 1 00:00:00 1970 From: lee.jones@linaro.org (Lee Jones) Date: Thu, 28 Aug 2014 14:14:12 +0100 Subject: [PATCH 06/11] mfd: htc-i2cpld: Rectify pointer offset error In-Reply-To: <1409231657-18294-1-git-send-email-lee.jones@linaro.org> References: <1409231657-18294-1-git-send-email-lee.jones@linaro.org> Message-ID: <1409231657-18294-6-git-send-email-lee.jones@linaro.org> To: linux-arm-kernel@lists.infradead.org List-Id: linux-arm-kernel.lists.infradead.org Checking the result of container_of() against NULL will always result to false. Using the offset of member 'chip_out' to find the start of 'struct htcpld_chip' will result in an offset error when .get_chip() is attempting to obtain 'htcpld-in'. Instead, we'll use the correct member based on a previously the set chip label. Signed-off-by: Lee Jones --- drivers/mfd/htc-i2cpld.c | 33 ++++++++++----------------------- 1 file changed, 10 insertions(+), 23 deletions(-) diff --git a/drivers/mfd/htc-i2cpld.c b/drivers/mfd/htc-i2cpld.c index 073e180..99b362e 100644 --- a/drivers/mfd/htc-i2cpld.c +++ b/drivers/mfd/htc-i2cpld.c @@ -258,31 +258,18 @@ static void htcpld_chip_set_ni(struct work_struct *work) static int htcpld_chip_get(struct gpio_chip *chip, unsigned offset) { struct htcpld_chip *chip_data; - int val = 0; - int is_input = 0; - - /* Try out first */ - chip_data = container_of(chip, struct htcpld_chip, chip_out); - if (!chip_data) { - /* Try in */ - is_input = 1; - chip_data = container_of(chip, struct htcpld_chip, chip_in); - if (!chip_data) - return -EINVAL; - } + u8 cache; - /* Determine if this is an input or output GPIO */ - if (!is_input) - /* Use the output cache */ - val = (chip_data->cache_out >> offset) & 1; - else - /* Use the input cache */ - val = (chip_data->cache_in >> offset) & 1; + if (!strncmp(chip->label, "htcpld-out", 10)) { + chip_data = container_of(chip, struct htcpld_chip, chip_out); + cache = chip_data->cache_out; + } else if (!strncmp(chip->label, "htcpld-in", 9)) { + chip_data = container_of(chip, struct htcpld_chip, chip_in); + cache = chip_data->cache_in; + } else + return -EINVAL; - if (val) - return 1; - else - return 0; + return (cache >> offset) & 1; } static int htcpld_direction_output(struct gpio_chip *chip, -- 1.9.1