diff options
| author | Simon Glass <sjg@chromium.org> | 2021-02-04 21:22:09 -0700 |
|---|---|---|
| committer | Tom Rini <trini@konsulko.com> | 2021-03-03 15:40:47 -0500 |
| commit | 8a45b2205749252f61d26508d5de9dcce020b2ef (patch) | |
| tree | fac56f635fb7a10236dd41868a0b1629184ab39c /drivers/gpio/sandbox.c | |
| parent | be04f1ab4291c724a65d86a743b8b7938f15a54c (diff) | |
| download | u-boot-8a45b2205749252f61d26508d5de9dcce020b2ef.tar.gz | |
gpio: Add a way to read 3-way strapping pins
Using the internal vs. external pull resistors it is possible to get
27 different combinations from 3 strapping pins. Add an implementation
of this.
This involves updating the sandbox GPIO driver to model external and
(weaker) internal pull resistors. The get_value() method now takes account
of what is driving a pin:
sandbox: GPIOD_EXT_DRIVEN - in which case GPIO_EXT_HIGH provides the
value
outside source - in which case GPIO_EXT_PULL_UP/DOWN indicates the
external state and we work the final state using those flags and
the internal GPIOD_PULL_UP/DOWN flags
Of course the outside source does not really exist in sandbox. We are just
modelling it for test purpose.
Signed-off-by: Simon Glass <sjg@chromium.org>
Diffstat (limited to 'drivers/gpio/sandbox.c')
| -rw-r--r-- | drivers/gpio/sandbox.c | 13 |
1 files changed, 9 insertions, 4 deletions
diff --git a/drivers/gpio/sandbox.c b/drivers/gpio/sandbox.c index 700098446b5..d008fdd2224 100644 --- a/drivers/gpio/sandbox.c +++ b/drivers/gpio/sandbox.c @@ -19,7 +19,6 @@ #include <dt-bindings/gpio/gpio.h> #include <dt-bindings/gpio/sandbox-gpio.h> - struct gpio_state { const char *label; /* label given by requester */ ulong flags; /* flags (GPIOD_...) */ @@ -81,10 +80,16 @@ int sandbox_gpio_get_value(struct udevice *dev, unsigned offset) if (get_gpio_flag(dev, offset, GPIOD_IS_OUT)) debug("sandbox_gpio: get_value on output gpio %u\n", offset); - if (state->flags & GPIOD_EXT_DRIVEN) + if (state->flags & GPIOD_EXT_DRIVEN) { val = state->flags & GPIOD_EXT_HIGH; - else - val = false; + } else { + if (state->flags & GPIOD_EXT_PULL_UP) + val = true; + else if (state->flags & GPIOD_EXT_PULL_DOWN) + val = false; + else + val = state->flags & GPIOD_PULL_UP; + } return val; } |