gpio: max730x: bring gpiochip_add_data after port config

gpiochip_add_data being called before might cause premature calls of
the gpiochip operations before the port_config values are initialized,
which would possibily write zeros to port configuration registers,
an operation not allowed. For example, if there are gpio-hog nodes
in a device-tree, the sequence of function calls are performed

gpiochip_add_data
of_gpiochip_add
of_gpiochip_scan_gpios
of_gpiochip_add_hog
gpiod_hog
gpiochip_request_own_desc
gpiod_configure_flags
gpiod_direction_output/gpiod_direction_input

which would call later the gpiochip operation direction_output or
direction_input prior the port_config[] initialization.

Moreover, gpiochip_get_data is replaced by the container_of macro
inside the gpiochip operations, which would allow the calling of
max7301_direction_input prior to gpiochip_add_data

Signed-off-by: Rodrigo Alencar <455.rodrigo.alencar@gmail.com>
[Bartosz: tweaked the commit message]
Signed-off-by: Bartosz Golaszewski <bgolaszewski@baylibre.com>

diff --git a/drivers/gpio/gpio-max730x.c b/drivers/gpio/gpio-max730x.c
index 1e1935c..b8c1fe2 100644 (file)
--- a/drivers/gpio/gpio-max730x.c
+++ b/drivers/gpio/gpio-max730x.c
@@ -47,7 +47,7 @@
 
 static int max7301_direction_input(struct gpio_chip *chip, unsigned offset)
 {
-       struct max7301 *ts = gpiochip_get_data(chip);
+       struct max7301 *ts = container_of(chip, struct max7301, chip);
        u8 *config;
        u8 offset_bits, pin_config;
        int ret;
@@ -89,7 +89,7 @@ static int __max7301_set(struct max7301 *ts, unsigned offset, int value)
 static int max7301_direction_output(struct gpio_chip *chip, unsigned offset,
                                    int value)
 {
-       struct max7301 *ts = gpiochip_get_data(chip);
+       struct max7301 *ts = container_of(chip, struct max7301, chip);
        u8 *config;
        u8 offset_bits;
        int ret;
@@ -189,10 +189,6 @@ int __max730x_probe(struct max7301 *ts)
        ts->chip.parent = dev;
        ts->chip.owner = THIS_MODULE;
 
-       ret = gpiochip_add_data(&ts->chip, ts);
-       if (ret)
-               goto exit_destroy;
-
        /*
         * initialize pullups according to platform data and cache the
         * register values for later use.
@@ -214,7 +210,9 @@ int __max730x_probe(struct max7301 *ts)
                }
        }
 
-       return ret;
+       ret = gpiochip_add_data(&ts->chip, ts);
+       if (!ret)
+               return ret;
 
 exit_destroy:
        mutex_destroy(&ts->lock);