gpio: sandbox: Add GPIOD_IS_AF for gpio configured in alternate function

This allows to test if a pin's label if displayed using gpio_get_status()
when this pin is configured in alternate function.

Signed-off-by: Patrice Chotard <patrice.chotard@foss.st.com>
Reviewed-by: Simon Glass <sjg@chromium.org>
Reviewed-by: Patrick Delaunay <patrick.delaunay@foss.st.com>

4 files changed, 39 insertions, 0 deletions

diff --git a/drivers/gpio/sandbox.c b/drivers/gpio/sandbox.c
index 106b2a7..305f9a6 100644
--- a/drivers/gpio/sandbox.c
+++ b/drivers/gpio/sandbox.c
@@ -196,6 +196,8 @@ static int sb_gpio_get_function(struct udevice *dev, unsigned offset)
 		return GPIOF_OUTPUT;
 	if (get_gpio_flag(dev, offset, GPIOD_IS_IN))
 		return GPIOF_INPUT;
+	if (get_gpio_flag(dev, offset, GPIOD_IS_AF))
+		return GPIOF_FUNC;
 
 	return GPIOF_INPUT; /*GPIO is not configurated */
 }
@@ -219,6 +221,9 @@ static int sb_gpio_xlate(struct udevice *dev, struct gpio_desc *desc,
 	if (args->args[1] & GPIO_OUT_ACTIVE)
 		desc->flags |= GPIOD_IS_OUT_ACTIVE;
 
+	if (args->args[1] & GPIO_AF)
+		desc->flags |= GPIOD_IS_AF;
+
 	return 0;
 }
 
diff --git a/include/asm-generic/gpio.h b/include/asm-generic/gpio.h
index 81f63f0..0fcf709 100644
--- a/include/asm-generic/gpio.h
+++ b/include/asm-generic/gpio.h
@@ -127,6 +127,7 @@ struct gpio_desc {
 #define GPIOD_OPEN_SOURCE	BIT(6)	/* GPIO is open source type */
 #define GPIOD_PULL_UP		BIT(7)	/* GPIO has pull-up enabled */
 #define GPIOD_PULL_DOWN		BIT(8)	/* GPIO has pull-down enabled */
+#define GPIOD_IS_AF		BIT(9)	/* GPIO is an alternate function */
 
 /* Flags for updating the above */
 #define GPIOD_MASK_DIR		(GPIOD_IS_OUT | GPIOD_IS_IN | \
diff --git a/include/dt-bindings/gpio/sandbox-gpio.h b/include/dt-bindings/gpio/sandbox-gpio.h
index e4bfdb3..05f9836 100644
--- a/include/dt-bindings/gpio/sandbox-gpio.h
+++ b/include/dt-bindings/gpio/sandbox-gpio.h
@@ -21,4 +21,7 @@
 /* Bit 18 express GPIO output is active */
 #define GPIO_OUT_ACTIVE		0x40000
 
+/* Bit 19 express GPIO set as alternate function */
+#define GPIO_AF			0x80000
+
 #endif
diff --git a/test/dm/gpio.c b/test/dm/gpio.c
index 33ae987..a8c35d4 100644
--- a/test/dm/gpio.c
+++ b/test/dm/gpio.c
@@ -778,3 +778,33 @@ static int dm_test_gpio_get_values_as_int_base3(struct unit_test_state *uts)
 }
 DM_TEST(dm_test_gpio_get_values_as_int_base3,
 	UT_TESTF_SCAN_PDATA | UT_TESTF_SCAN_FDT);
+
+/* Check that gpio_get_status return the label of a GPIO configured as GPIOD_AF */
+static int dm_test_gpio_function(struct unit_test_state *uts)
+{
+	struct gpio_desc desc;
+	struct udevice *dev;
+	ulong flags;
+	unsigned int offset, gpio;
+	char buf[80];
+
+	ut_assertok(uclass_get_device(UCLASS_TEST_FDT, 0, &dev));
+	ut_asserteq_str("a-test", dev->name);
+
+	/* request gpio_b 5 */
+	ut_assertok(gpio_request_by_name(dev, "test-gpios", 2, &desc, 0));
+	/* update gpio_b 5 function to GPIO_AF */
+	ut_assertok(dm_gpio_clrset_flags(&desc, GPIOD_IS_AF, GPIOD_IS_AF));
+	ut_assertok(dm_gpio_get_flags(&desc, &flags));
+	ut_asserteq(GPIOD_IS_AF, flags);
+	/* check using gpio_get_status that label is displayed for a pin with GPIO_AF function */
+	ut_assertok(gpio_lookup_name("b5", &dev, &offset, &gpio));
+	ut_assertok(gpio_get_status(dev, offset, buf, sizeof(buf)));
+	ut_asserteq_str("b5: func a-test.test-gpios2", buf);
+
+	ut_assertok(dm_gpio_free(dev, &desc));
+
+	return 0;
+}
+DM_TEST(dm_test_gpio_function,
+	UT_TESTF_SCAN_PDATA | UT_TESTF_SCAN_FDT);