summaryrefslogtreecommitdiffstats
path: root/drivers/gpio
diff options
context:
space:
mode:
authorRodrigo Alencar <455.rodrigo.alencar@gmail.com>2020-05-14 10:00:12 -0300
committerBartosz Golaszewski <bgolaszewski@baylibre.com>2020-05-22 17:01:25 +0200
commit47a3734b03904bbccbba0c8f78cf2b0f0aa157e7 (patch)
treea8f48093f23c5117d6ccc7eceb9a52d40bf157e3 /drivers/gpio
parent3831c051dfbf58595085e432acc00ad4efcf54cc (diff)
downloadlinux-stable-47a3734b03904bbccbba0c8f78cf2b0f0aa157e7.tar.gz
linux-stable-47a3734b03904bbccbba0c8f78cf2b0f0aa157e7.tar.bz2
linux-stable-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.c12
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);