dm: gpio: Add a way to update flags

It is convenient to be able to adjust some of the flags for a GPIO while
leaving others alone. Add a function for this.

Update dm_gpio_set_dir_flags() to make use of this.

Also update dm_gpio_set_value() to use this also, since this allows the
open-drain / open-source features to be implemented directly in the
driver, rather than using the uclass workaround.

Update the sandbox tests accordingly. This involves a lot of changes to
dm_test_gpio_opendrain_opensource() since we no-longer have the direciion
being reported differently depending on the open drain/open source flags.

Also update the STM32 drivers to let the uclass handle the active low/high
logic.

Drop the GPIOD_FLAGS_OUTPUT() macro which is no-longer used.

Signed-off-by: Simon Glass <sjg@chromium.org>
Tested-by: Kory Maincent <kory.maincent@bootlin.com>
Reviewed-by: Patrick Delaunay <patrick.delaunay@foss.st.com>
Tested-by: Patrick Delaunay <patrick.delaunay@foss.st.com>
Reviewed-by: Patrick Delaunay <patrick.delaunay@foss.st.com>
Tested-by: Patrick Delaunay <patrick.delaunay@foss.st.com>

1 files changed, 25 insertions, 6 deletions

diff --git a/include/asm-generic/gpio.h b/include/asm-generic/gpio.h
index 4f8d1938da..7d1e19ad53 100644
--- a/include/asm-generic/gpio.h
+++ b/include/asm-generic/gpio.h
@@ -128,6 +128,12 @@ struct gpio_desc {
 #define GPIOD_PULL_UP		BIT(7)	/* GPIO has pull-up enabled */
 #define GPIOD_PULL_DOWN		BIT(8)	/* GPIO has pull-down enabled */
 
+/* Flags for updating the above */
+#define GPIOD_MASK_DIR		(GPIOD_IS_OUT | GPIOD_IS_IN | \
+					GPIOD_IS_OUT_ACTIVE)
+#define GPIOD_MASK_DSTYPE	(GPIOD_OPEN_DRAIN | GPIOD_OPEN_SOURCE)
+#define GPIOD_MASK_PULL		(GPIOD_PULL_UP | GPIOD_PULL_DOWN)
+
 	uint offset;		/* GPIO offset within the device */
 	/*
 	 * We could consider adding the GPIO label in here. Possibly we could
@@ -135,12 +141,6 @@ struct gpio_desc {
 	 */
 };
 
-/* helper to compute the value of the gpio output */
-#define GPIOD_FLAGS_OUTPUT_MASK (GPIOD_ACTIVE_LOW | GPIOD_IS_OUT_ACTIVE)
-#define GPIOD_FLAGS_OUTPUT(flags) \
-	(((((flags) & GPIOD_FLAGS_OUTPUT_MASK) == GPIOD_IS_OUT_ACTIVE) || \
-	  (((flags) & GPIOD_FLAGS_OUTPUT_MASK) == GPIOD_ACTIVE_LOW)))
-
 /**
  * dm_gpio_is_valid() - Check if a GPIO is valid
  *
@@ -669,6 +669,25 @@ int dm_gpio_set_value(const struct gpio_desc *desc, int value);
 int dm_gpio_set_dir(struct gpio_desc *desc);
 
 /**
+ * dm_gpio_clrset_flags() - Update flags
+ *
+ * This updates the flags as directled. Note that desc->flags is updated by this
+ * function on success. If any changes cannot be made, best efforts are made.
+ *
+ * By use of @clr and @set any of flags can be individually updated, or left
+ * alone
+ *
+ * @desc:	GPIO description containing device, offset and flags,
+ *		previously returned by gpio_request_by_name()
+ * @clr:	Flags to clear (GPIOD_...)
+ * @set:	Flags to set (GPIOD_...)
+ * @return 0 if OK, -EINVAL if the flags had obvious conflicts,
+ * -ERECALLCONFLICT if there was a non-obvious hardware conflict when attempting
+ * to set the flags
+ */
+int dm_gpio_clrset_flags(struct gpio_desc *desc, ulong clr, ulong set);
+
+/**
  * dm_gpio_set_dir_flags() - Set direction using description and added flags
  *
  * This sets up the direction according to the provided flags and the GPIO