diff options
| author |   Rodrigo Alencar <455.rodrigo.alencar@gmail.com> | 2020-05-14 10:00:12 -0300 |
|---|---|---|
| committer |   Bartosz Golaszewski <bgolaszewski@baylibre.com> | 2020-05-22 17:01:25 +0200 |
| commit | 47a3734b03904bbccbba0c8f78cf2b0f0aa157e7 (patch) | |
| tree | a8f48093f23c5117d6ccc7eceb9a52d40bf157e3 /drivers/gpio | |
| parent | tools: gpio: add bias flags to lsgpio (diff) | |
| download | wireguard-linux-47a3734b03904bbccbba0c8f78cf2b0f0aa157e7.tar.xz wireguard-linux-47a3734b03904bbccbba0c8f78cf2b0f0aa157e7.zip | |
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>
Diffstat (limited to 'drivers/gpio')
| -rw-r--r-- | drivers/gpio/gpio-max730x.c | 12 |
1 files changed, 5 insertions, 7 deletions
diff --git a/drivers/gpio/gpio-max730x.c b/drivers/gpio/gpio-max730x.c index 1e1935c51096..b8c1fe20f49a 100644 --- 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); |