[PATCH 06/11] mfd: htc-i2cpld: Rectify pointer offset error

Lee Jones
2014-08-28T13:14:43Z

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 <lee.jones@linaro.org>
---
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