[PATCH v4 07/35] gpio: Add a method to convert a GPIO to ACPI
Simon Glass
sjg at chromium.org
Tue Jul 7 21:11:44 CEST 2020
When generating ACPI tables we need to convert GPIOs in U-Boot to the ACPI
structures required by ACPI. This is a SoC-specific conversion and cannot
be handled by generic code, so add a new GPIO method to do the conversion.
Signed-off-by: Simon Glass <sjg at chromium.org>
Reviewed-by: Wolfgang Wallner <wolfgang.wallner at br-automation.com>
---
Changes in v4:
- Use memset() to zero struct acpi_gpio in gpio_get_acpi()
- Move common code about the if...else in sb_gpio_get_acpi()
- Don't set zero fields in sb_gpio_get_acpi(), and add a comment about it
- Update acpi_device_write_interrupt_irq() to return IRQ pin number
Changes in v1:
- Update sandbox driver slightly for testing
drivers/gpio/gpio-uclass.c | 22 ++++++++++
drivers/gpio/sandbox.c | 77 ++++++++++++++++++++++++++++++++
include/acpi/acpi_device.h | 90 ++++++++++++++++++++++++++++++++++++++
include/asm-generic/gpio.h | 27 ++++++++++++
test/dm/gpio.c | 62 ++++++++++++++++++++++++++
5 files changed, 278 insertions(+)
diff --git a/drivers/gpio/gpio-uclass.c b/drivers/gpio/gpio-uclass.c
index 9eeab22eef..3b964faf18 100644
--- a/drivers/gpio/gpio-uclass.c
+++ b/drivers/gpio/gpio-uclass.c
@@ -13,6 +13,7 @@
#include <errno.h>
#include <fdtdec.h>
#include <malloc.h>
+#include <acpi/acpi_device.h>
#include <asm/gpio.h>
#include <dm/device_compat.h>
#include <linux/bug.h>
@@ -809,6 +810,27 @@ int gpio_get_status(struct udevice *dev, int offset, char *buf, int buffsize)
return 0;
}
+#if CONFIG_IS_ENABLED(ACPIGEN)
+int gpio_get_acpi(const struct gpio_desc *desc, struct acpi_gpio *gpio)
+{
+ struct dm_gpio_ops *ops;
+
+ memset(gpio, '\0', sizeof(*gpio));
+ if (!dm_gpio_is_valid(desc)) {
+ /* Indicate that the GPIO is not valid */
+ gpio->pin_count = 0;
+ gpio->pins[0] = 0;
+ return -EINVAL;
+ }
+
+ ops = gpio_get_ops(desc->dev);
+ if (!ops->get_acpi)
+ return -ENOSYS;
+
+ return ops->get_acpi(desc, gpio);
+}
+#endif
+
int gpio_claim_vector(const int *gpio_num_array, const char *fmt)
{
int i, ret;
diff --git a/drivers/gpio/sandbox.c b/drivers/gpio/sandbox.c
index b9a1d65acc..c2f80472b8 100644
--- a/drivers/gpio/sandbox.c
+++ b/drivers/gpio/sandbox.c
@@ -8,7 +8,9 @@
#include <fdtdec.h>
#include <log.h>
#include <malloc.h>
+#include <acpi/acpi_device.h>
#include <asm/gpio.h>
+#include <dm/acpi.h>
#include <dm/device_compat.h>
#include <dm/lists.h>
#include <dm/of.h>
@@ -197,6 +199,63 @@ static int sb_gpio_get_dir_flags(struct udevice *dev, unsigned int offset,
return 0;
}
+#if CONFIG_IS_ENABLED(ACPIGEN)
+static int sb_gpio_get_acpi(const struct gpio_desc *desc,
+ struct acpi_gpio *gpio)
+{
+ int ret;
+
+ /* Note that gpio_get_acpi() zeroes *gpio before calling here */
+ gpio->pin_count = 1;
+ gpio->pins[0] = desc->offset;
+ ret = acpi_device_scope(desc->dev, gpio->resource,
+ sizeof(gpio->resource));
+ if (ret)
+ return log_ret(ret);
+
+ /* All of these values are just used for testing */
+ if (desc->flags & GPIOD_ACTIVE_LOW) {
+ gpio->pin0_addr = 0x80012 + desc->offset;
+ gpio->type = ACPI_GPIO_TYPE_INTERRUPT;
+ gpio->pull = ACPI_GPIO_PULL_DOWN;
+ gpio->interrupt_debounce_timeout = 4321;
+
+ /* We use the GpioInt part */
+ gpio->irq.pin = desc->offset;
+ gpio->irq.polarity = ACPI_IRQ_ACTIVE_BOTH;
+ gpio->irq.shared = ACPI_IRQ_SHARED;
+ gpio->irq.wake = ACPI_IRQ_WAKE;
+
+ /* The GpioIo part is only used for testing */
+ gpio->polarity = ACPI_GPIO_ACTIVE_LOW;
+ } else {
+ gpio->pin0_addr = 0xc00dc + desc->offset;
+ gpio->type = ACPI_GPIO_TYPE_IO;
+ gpio->pull = ACPI_GPIO_PULL_UP;
+ gpio->interrupt_debounce_timeout = 0;
+
+ /* The GpioInt part is not used */
+
+ /* We use the GpioIo part */
+ gpio->output_drive_strength = 1234;
+ gpio->io_shared = true;
+ gpio->io_restrict = ACPI_GPIO_IO_RESTRICT_INPUT;
+ gpio->polarity = 0;
+ }
+
+ return 0;
+}
+
+static int sb_gpio_get_name(const struct udevice *dev, char *out_name)
+{
+ return acpi_copy_name(out_name, "GPIO");
+}
+
+struct acpi_ops gpio_sandbox_acpi_ops = {
+ .get_name = sb_gpio_get_name,
+};
+#endif /* ACPIGEN */
+
static const struct dm_gpio_ops gpio_sandbox_ops = {
.direction_input = sb_gpio_direction_input,
.direction_output = sb_gpio_direction_output,
@@ -206,6 +265,9 @@ static const struct dm_gpio_ops gpio_sandbox_ops = {
.xlate = sb_gpio_xlate,
.set_dir_flags = sb_gpio_set_dir_flags,
.get_dir_flags = sb_gpio_get_dir_flags,
+#if CONFIG_IS_ENABLED(ACPIGEN)
+ .get_acpi = sb_gpio_get_acpi,
+#endif
};
static int sandbox_gpio_ofdata_to_platdata(struct udevice *dev)
@@ -252,6 +314,7 @@ U_BOOT_DRIVER(sandbox_gpio) = {
.probe = gpio_sandbox_probe,
.remove = gpio_sandbox_remove,
.ops = &gpio_sandbox_ops,
+ ACPI_OPS_PTR(&gpio_sandbox_acpi_ops)
};
U_BOOT_DRIVER_ALIAS(sandbox_gpio, sandbox_gpio_alias)
@@ -421,6 +484,13 @@ static int sb_pinctrl_get_pin_muxing(struct udevice *dev,
return 0;
}
+#if CONFIG_IS_ENABLED(ACPIGEN)
+static int sb_pinctrl_get_name(const struct udevice *dev, char *out_name)
+{
+ return acpi_copy_name(out_name, "PINC");
+}
+#endif
+
static int sandbox_pinctrl_probe(struct udevice *dev)
{
struct sb_pinctrl_priv *priv = dev_get_priv(dev);
@@ -436,6 +506,12 @@ static struct pinctrl_ops sandbox_pinctrl_gpio_ops = {
.get_pin_muxing = sb_pinctrl_get_pin_muxing,
};
+#if CONFIG_IS_ENABLED(ACPIGEN)
+struct acpi_ops pinctrl_sandbox_acpi_ops = {
+ .get_name = sb_pinctrl_get_name,
+};
+#endif
+
static const struct udevice_id sandbox_pinctrl_gpio_match[] = {
{ .compatible = "sandbox,pinctrl-gpio" },
{ /* sentinel */ }
@@ -449,4 +525,5 @@ U_BOOT_DRIVER(sandbox_pinctrl_gpio) = {
.bind = dm_scan_fdt_dev,
.probe = sandbox_pinctrl_probe,
.priv_auto_alloc_size = sizeof(struct sb_pinctrl_priv),
+ ACPI_OPS_PTR(&pinctrl_sandbox_acpi_ops)
};
diff --git a/include/acpi/acpi_device.h b/include/acpi/acpi_device.h
index e72fede54c..69b90968a8 100644
--- a/include/acpi/acpi_device.h
+++ b/include/acpi/acpi_device.h
@@ -92,6 +92,96 @@ struct acpi_irq {
enum acpi_irq_wake wake;
};
+/**
+ * enum acpi_gpio_type - type of the descriptor
+ *
+ * @ACPI_GPIO_TYPE_INTERRUPT: GpioInterrupt
+ * @ACPI_GPIO_TYPE_IO: GpioIo
+ */
+enum acpi_gpio_type {
+ ACPI_GPIO_TYPE_INTERRUPT,
+ ACPI_GPIO_TYPE_IO,
+};
+
+/**
+ * enum acpi_gpio_pull - pull direction
+ *
+ * @ACPI_GPIO_PULL_DEFAULT: Use default value for pin
+ * @ACPI_GPIO_PULL_UP: Pull up
+ * @ACPI_GPIO_PULL_DOWN: Pull down
+ * @ACPI_GPIO_PULL_NONE: No pullup/pulldown
+ */
+enum acpi_gpio_pull {
+ ACPI_GPIO_PULL_DEFAULT,
+ ACPI_GPIO_PULL_UP,
+ ACPI_GPIO_PULL_DOWN,
+ ACPI_GPIO_PULL_NONE,
+};
+
+/**
+ * enum acpi_gpio_io_restrict - controls input/output of pin
+ *
+ * @ACPI_GPIO_IO_RESTRICT_NONE: no restrictions
+ * @ACPI_GPIO_IO_RESTRICT_INPUT: input only (no output)
+ * @ACPI_GPIO_IO_RESTRICT_OUTPUT: output only (no input)
+ * @ACPI_GPIO_IO_RESTRICT_PRESERVE: preserve settings when driver not active
+ */
+enum acpi_gpio_io_restrict {
+ ACPI_GPIO_IO_RESTRICT_NONE,
+ ACPI_GPIO_IO_RESTRICT_INPUT,
+ ACPI_GPIO_IO_RESTRICT_OUTPUT,
+ ACPI_GPIO_IO_RESTRICT_PRESERVE,
+};
+
+/** enum acpi_gpio_polarity - controls the GPIO polarity */
+enum acpi_gpio_polarity {
+ ACPI_GPIO_ACTIVE_HIGH = 0,
+ ACPI_GPIO_ACTIVE_LOW = 1,
+};
+
+#define ACPI_GPIO_REVISION_ID 1
+#define ACPI_GPIO_MAX_PINS 2
+
+/**
+ * struct acpi_gpio - representation of an ACPI GPIO
+ *
+ * @pin_count: Number of pins represented
+ * @pins: List of pins
+ * @pin0_addr: Address in memory of the control registers for pin 0. This is
+ * used when generating ACPI tables
+ * @type: GPIO type
+ * @pull: Pullup/pulldown setting
+ * @resource: Resource name for this GPIO controller
+ * For GpioInt:
+ * @interrupt_debounce_timeout: Debounce timeout in units of 10us
+ * @irq: Interrupt
+ *
+ * For GpioIo:
+ * @output_drive_strength: Drive strength in units of 10uA
+ * @io_shared; true if GPIO is shared
+ * @io_restrict: I/O restriction setting
+ * @polarity: GPIO polarity
+ */
+struct acpi_gpio {
+ int pin_count;
+ u16 pins[ACPI_GPIO_MAX_PINS];
+ ulong pin0_addr;
+
+ enum acpi_gpio_type type;
+ enum acpi_gpio_pull pull;
+ char resource[ACPI_PATH_MAX];
+
+ /* GpioInt */
+ u16 interrupt_debounce_timeout;
+ struct acpi_irq irq;
+
+ /* GpioIo */
+ u16 output_drive_strength;
+ bool io_shared;
+ enum acpi_gpio_io_restrict io_restrict;
+ enum acpi_gpio_polarity polarity;
+};
+
/**
* acpi_device_path() - Get the full path to an ACPI device
*
diff --git a/include/asm-generic/gpio.h b/include/asm-generic/gpio.h
index e16c2f31d9..a57dd2665c 100644
--- a/include/asm-generic/gpio.h
+++ b/include/asm-generic/gpio.h
@@ -10,6 +10,7 @@
#include <dm/ofnode.h>
#include <linux/bitops.h>
+struct acpi_gpio;
struct ofnode_phandle_args;
/*
@@ -329,6 +330,20 @@ struct dm_gpio_ops {
*/
int (*get_dir_flags)(struct udevice *dev, unsigned int offset,
ulong *flags);
+
+#if CONFIG_IS_ENABLED(ACPIGEN)
+ /**
+ * get_acpi() - Get the ACPI info for a GPIO
+ *
+ * This converts a GPIO to an ACPI structure for adding to the ACPI
+ * tables.
+ *
+ * @desc: GPIO description to convert
+ * @gpio: Output ACPI GPIO information
+ * @return ACPI pin number or -ve on error
+ */
+ int (*get_acpi)(const struct gpio_desc *desc, struct acpi_gpio *gpio);
+#endif
};
/**
@@ -674,4 +689,16 @@ int dm_gpio_get_dir_flags(struct gpio_desc *desc, ulong *flags);
*/
int gpio_get_number(const struct gpio_desc *desc);
+/**
+ * gpio_get_acpi() - Get the ACPI pin for a GPIO
+ *
+ * This converts a GPIO to an ACPI pin number for adding to the ACPI
+ * tables. If the GPIO is invalid, the pin_count and pins[0] are set to 0
+ *
+ * @desc: GPIO description to convert
+ * @gpio: Output ACPI GPIO information
+ * @return ACPI pin number or -ve on error
+ */
+int gpio_get_acpi(const struct gpio_desc *desc, struct acpi_gpio *gpio);
+
#endif /* _ASM_GENERIC_GPIO_H_ */
diff --git a/test/dm/gpio.c b/test/dm/gpio.c
index 57293f2179..d44f1159ff 100644
--- a/test/dm/gpio.c
+++ b/test/dm/gpio.c
@@ -8,6 +8,7 @@
#include <dm.h>
#include <log.h>
#include <malloc.h>
+#include <acpi/acpi_device.h>
#include <dm/root.h>
#include <dm/test.h>
#include <dm/util.h>
@@ -385,3 +386,64 @@ static int dm_test_gpio_get_dir_flags(struct unit_test_state *uts)
return 0;
}
DM_TEST(dm_test_gpio_get_dir_flags, DM_TESTF_SCAN_PDATA | DM_TESTF_SCAN_FDT);
+
+/* Test of gpio_get_acpi() */
+static int dm_test_gpio_get_acpi(struct unit_test_state *uts)
+{
+ struct acpi_gpio agpio;
+ struct udevice *dev;
+ struct gpio_desc desc;
+
+ ut_assertok(uclass_get_device(UCLASS_TEST_FDT, 0, &dev));
+ ut_asserteq_str("a-test", dev->name);
+ ut_assertok(gpio_request_by_name(dev, "test-gpios", 1, &desc, 0));
+
+ /* See sb_gpio_get_acpi() */
+ ut_assertok(gpio_get_acpi(&desc, &agpio));
+ ut_asserteq(1, agpio.pin_count);
+ ut_asserteq(4, agpio.pins[0]);
+ ut_asserteq(ACPI_GPIO_TYPE_IO, agpio.type);
+ ut_asserteq(ACPI_GPIO_PULL_UP, agpio.pull);
+ ut_asserteq_str("\\_SB.PINC", agpio.resource);
+ ut_asserteq(0, agpio.interrupt_debounce_timeout);
+ ut_asserteq(0, agpio.irq.pin);
+ ut_asserteq(1234, agpio.output_drive_strength);
+ ut_asserteq(true, agpio.io_shared);
+ ut_asserteq(ACPI_GPIO_IO_RESTRICT_INPUT, agpio.io_restrict);
+ ut_asserteq(ACPI_GPIO_ACTIVE_HIGH, agpio.polarity);
+
+ return 0;
+}
+DM_TEST(dm_test_gpio_get_acpi, DM_TESTF_SCAN_PDATA | DM_TESTF_SCAN_FDT);
+
+/* Test of gpio_get_acpi() with an interrupt GPIO */
+static int dm_test_gpio_get_acpi_irq(struct unit_test_state *uts)
+{
+ struct acpi_gpio agpio;
+ struct udevice *dev;
+ struct gpio_desc desc;
+
+ ut_assertok(uclass_get_device(UCLASS_TEST_FDT, 0, &dev));
+ ut_asserteq_str("a-test", dev->name);
+ ut_assertok(gpio_request_by_name(dev, "test2-gpios", 2, &desc, 0));
+
+ /* See sb_gpio_get_acpi() */
+ ut_assertok(gpio_get_acpi(&desc, &agpio));
+ ut_asserteq(1, agpio.pin_count);
+ ut_asserteq(6, agpio.pins[0]);
+ ut_asserteq(ACPI_GPIO_TYPE_INTERRUPT, agpio.type);
+ ut_asserteq(ACPI_GPIO_PULL_DOWN, agpio.pull);
+ ut_asserteq_str("\\_SB.PINC", agpio.resource);
+ ut_asserteq(4321, agpio.interrupt_debounce_timeout);
+ ut_asserteq(6, agpio.irq.pin);
+ ut_asserteq(ACPI_IRQ_ACTIVE_BOTH, agpio.irq.polarity);
+ ut_asserteq(ACPI_IRQ_SHARED, agpio.irq.shared);
+ ut_asserteq(true, agpio.irq.wake);
+ ut_asserteq(0, agpio.output_drive_strength);
+ ut_asserteq(false, agpio.io_shared);
+ ut_asserteq(0, agpio.io_restrict);
+ ut_asserteq(ACPI_GPIO_ACTIVE_LOW, agpio.polarity);
+
+ return 0;
+}
+DM_TEST(dm_test_gpio_get_acpi_irq, DM_TESTF_SCAN_PDATA | DM_TESTF_SCAN_FDT);
--
2.27.0.383.g050319c2ae-goog
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