diff options
| author | Patrick Delaunay | 2020-01-13 11:35:07 +0100 |
|---|---|---|
| committer | Tom Rini | 2020-04-16 23:06:54 -0400 |
| commit | 477ca57b9a53120a14bdca356612fce15211345d (patch) | |
| tree | 8ede882b3395eda2e70c38d8b4ad1b1772e6bc7b /drivers/gpio | |
| parent | 695e5fd5469ab052126c4cb30c4d26e6058de067 (diff) | |
gpio: add support of new GPIO direction flag
This commit manages the new dir flags that can be used in gpio
specifiers to indicate the pull-up or pull-down resistor
configuration for output gpio (GPIO_PULL_UP, GPIO_PULL_DOWN)
or the Open Drain/Open Source configuration for input gpio
(GPIO_OPEN_DRAIN, GPIO_OPEN_SOURCE).
These flags are already supported in Linux kernel in gpio lib.
This patch only parse and save the direction flags in GPIO
descriptor (desc->flags), it prepares the introduction of new ops
to manage them.
The GPIO uclass supports new GPIO flags from device-tree
(GPIO_XXX define in include/dt-bindings/gpio/gpio.h)
and translate them in the dir flags (GPIOD_XXX):
- GPIO_PULL_UP => GPIOD_PULL_UP
- GPIO_PULL_DOWN => GPIOD_PULL_DOWN
- GPIO_OPEN_DRAIN => GPIOD_OPEN_DRAIN
- GPIO_OPEN_SOURCE => GPIOD_OPEN_SOURCE
This patch also adds protection in the check_dir_flags function for
new invalid configuration of the dir flags.
Signed-off-by: Patrick Delaunay <patrick.delaunay@st.com>
Reviewed-by: Simon Glass <sjg@chromium.org>
Diffstat (limited to 'drivers/gpio')
| -rw-r--r-- | drivers/gpio/gpio-uclass.c | 30 |
1 files changed, 30 insertions, 0 deletions
diff --git a/drivers/gpio/gpio-uclass.c b/drivers/gpio/gpio-uclass.c index 9550e45e6cd..25263994d24 100644 --- a/drivers/gpio/gpio-uclass.c +++ b/drivers/gpio/gpio-uclass.c @@ -145,6 +145,24 @@ int gpio_xlate_offs_flags(struct udevice *dev, struct gpio_desc *desc, if (args->args[1] & GPIO_ACTIVE_LOW) desc->flags |= GPIOD_ACTIVE_LOW; + /* + * need to test 2 bits for gpio output binding: + * OPEN_DRAIN (0x6) = SINGLE_ENDED (0x2) | LINE_OPEN_DRAIN (0x4) + * OPEN_SOURCE (0x2) = SINGLE_ENDED (0x2) | LINE_OPEN_SOURCE (0x0) + */ + if (args->args[1] & GPIO_SINGLE_ENDED) { + if (args->args[1] & GPIO_LINE_OPEN_DRAIN) + desc->flags |= GPIOD_OPEN_DRAIN; + else + desc->flags |= GPIOD_OPEN_SOURCE; + } + + if (args->args[1] & GPIO_PULL_UP) + desc->flags |= GPIOD_PULL_UP; + + if (args->args[1] & GPIO_PULL_DOWN) + desc->flags |= GPIOD_PULL_DOWN; + return 0; } @@ -521,6 +539,18 @@ static int check_dir_flags(ulong flags) return -EINVAL; } + if ((flags & GPIOD_PULL_UP) && (flags & GPIOD_PULL_DOWN)) { + log_debug("%s: flags 0x%lx has GPIOD_PULL_UP and GPIOD_PULL_DOWN\n", + __func__, flags); + return -EINVAL; + } + + if ((flags & GPIOD_OPEN_DRAIN) && (flags & GPIOD_OPEN_SOURCE)) { + log_debug("%s: flags 0x%lx has GPIOD_OPEN_DRAIN and GPIOD_OPEN_SOURCE\n", + __func__, flags); + return -EINVAL; + } + return 0; } |