diff mbox series

[v2,29/39] acpi: Add generation code for devices

Message ID 20200308214442.v2.29.I06704ecd3c988c7826720a7f447e0388bfe85808@changeid
State New
Headers show
Series dm: Add programmatic generation of ACPI tables (part A) | expand

Commit Message

Simon Glass March 9, 2020, 3:44 a.m. UTC
Some devices need to create ACPI tables to communcate their parameters
to Linux. Add support for this.

Signed-off-by: Simon Glass <sjg at chromium.org>
---

Changes in v2:
- Drop CID value from i2c struct

 include/acpi_device.h  |  705 ++++++++++++++++++++++++++
 lib/acpi/acpi_device.c | 1094 ++++++++++++++++++++++++++++++++++++++++
 2 files changed, 1799 insertions(+)
 create mode 100644 include/acpi_device.h
 create mode 100644 lib/acpi/acpi_device.c
diff mbox series

Patch

diff --git a/include/acpi_device.h b/include/acpi_device.h
new file mode 100644
index 0000000000..f97bd075ec
--- /dev/null
+++ b/include/acpi_device.h
@@ -0,0 +1,705 @@ 
+/* SPDX-License-Identifier: GPL-2.0 */
+/*
+ * Generation of tables for particular device types
+ *
+ * Copyright 2019 Google LLC
+ * Mostly taken from coreboot file of the same name
+ */
+
+#ifndef __ACPI_DEVICE_H
+#define __ACPI_DEVICE_H
+
+#include <i2c.h>
+#include <irq.h>
+#include <spi.h>
+#include <asm-generic/gpio.h>
+
+struct acpi_ctx;
+struct irq;
+struct gpio_desc;
+struct udevice;
+
+/**
+ * enum acpi_dp_type - types of device property objects
+ *
+ * These refer to the types defined by struct acpi_dp below
+ *
+ * @ACPI_DP_TYPE_UNKNOWN: Unknown / do not use
+ * @ACPI_DP_TYPE_INTEGER: Integer value (u64) in @integer
+ * @ACPI_DP_TYPE_STRING: String value in @string
+ * @ACPI_DP_TYPE_REFERENCE: Reference to another object, with value in @string
+ * @ACPI_DP_TYPE_TABLE: Type for a top-level table which may have children
+ * @ACPI_DP_TYPE_ARRAY: Array of items with first item in @array and following
+ *	items linked from that item's @next
+ * @ACPI_DP_TYPE_CHILD: Child object, with siblings in that child's @next
+ */
+enum acpi_dp_type {
+	ACPI_DP_TYPE_UNKNOWN,
+	ACPI_DP_TYPE_INTEGER,
+	ACPI_DP_TYPE_STRING,
+	ACPI_DP_TYPE_REFERENCE,
+	ACPI_DP_TYPE_TABLE,
+	ACPI_DP_TYPE_ARRAY,
+	ACPI_DP_TYPE_CHILD,
+};
+
+/* ACPI descriptor values for common descriptors: SERIAL_BUS means I2C */
+#define ACPI_DESCRIPTOR_LARGE		BIT(7)
+#define ACPI_DESCRIPTOR_INTERRUPT	(ACPI_DESCRIPTOR_LARGE | 9)
+#define ACPI_DESCRIPTOR_GPIO		(ACPI_DESCRIPTOR_LARGE | 12)
+#define ACPI_DESCRIPTOR_SERIAL_BUS	(ACPI_DESCRIPTOR_LARGE | 14)
+
+/*
+ * PRP0001 is a special DT namespace link device ID. It provides a means to use
+ * existing DT-compatible device identification in ACPI. When this _HID is used
+ * by an ACPI device, the ACPI subsystem in OS looks up "compatible" property in
+ * the device object's _DSD and will use the value of that property to identify
+ * the corresponding device in analogy with the original DT device
+ * identification algorithm.
+ * More details can be found in Linux kernel documentation:
+ * Documentation/acpi/enumeration.txt
+ */
+#define ACPI_DT_NAMESPACE_HID		"PRP0001"
+
+/* Length of a full path to an ACPI device */
+#define ACPI_PATH_MAX		30
+
+/**
+ * acpi_device_name() - Locate and return the ACPI name for this device
+ *
+ * @dev: Device to check
+ * @name: Returns the character name, must be at least ACPI_NAME_MAX long
+ * @return 0 if OK, -ve on error
+ */
+int acpi_device_name(const struct udevice *dev, char *name);
+
+/**
+ * acpi_device_path() - Get the full path to an ACPI device
+ *
+ * This gets the full path in the form XXXX.YYYY.ZZZZ where XXXX is the root
+ * and ZZZZ is the device. All parent devices are added to the path.
+ *
+ * @dev: Device to check
+ * @buf: Buffer to place the path in (should be ACPI_PATH_MAX long)
+ * @maxlen: Size of buffer (typically ACPI_PATH_MAX)
+ * @return 0 if OK, -ve on error
+ */
+int acpi_device_path(const struct udevice *dev, char *buf, int maxlen);
+
+/**
+ * acpi_device_scope() - Get the scope of an ACPI device
+ *
+ * This gets the scope which is the full path of the parent device, as per
+ * acpi_device_path().
+ *
+ * @dev: Device to check
+ * @buf: Buffer to place the path in (should be ACPI_PATH_MAX long)
+ * @maxlen: Size of buffer (typically ACPI_PATH_MAX)
+ * @return 0 if OK, -EINVAL if the device has no parent, other -ve on other
+ *	error
+ */
+int acpi_device_scope(const struct udevice *dev, char *scope, int maxlen);
+
+/**
+ * acpi_device_status() - Get the status of a device
+ *
+ * This currently just returns ACPI_STATUS_DEVICE_ALL_ON. It does not support
+ * inactive or hidden devices.
+ *
+ * @dev: Device to check
+ * @return device status, as ACPI_STATUS_DEVICE_...
+ */
+int acpi_device_status(const struct udevice *dev);
+
+/** enum acpi_irq_mode - edge/level trigger mode */
+enum acpi_irq_mode {
+	ACPI_IRQ_EDGE_TRIGGERED,
+	ACPI_IRQ_LEVEL_TRIGGERED,
+};
+
+/**
+ * enum acpi_irq_polarity - polarity of interrupt
+ *
+ * @ACPI_IRQ_ACTIVE_LOW - for ACPI_IRQ_EDGE_TRIGGERED this means falling edge
+ * @ACPI_IRQ_ACTIVE_HIGH - for ACPI_IRQ_EDGE_TRIGGERED this means rising edge
+ * @ACPI_IRQ_ACTIVE_BOTH - not meaningful for ACPI_IRQ_EDGE_TRIGGERED
+ */
+enum acpi_irq_polarity {
+	ACPI_IRQ_ACTIVE_LOW,
+	ACPI_IRQ_ACTIVE_HIGH,
+	ACPI_IRQ_ACTIVE_BOTH,
+};
+
+/**
+ * enum acpi_irq_shared - whether interrupt is shared or not
+ *
+ * @ACPI_IRQ_EXCLUSIVE: only this device uses the interrupt
+ * @ACPI_IRQ_SHARED: other devices may use this interrupt
+ */
+enum acpi_irq_shared {
+	ACPI_IRQ_EXCLUSIVE,
+	ACPI_IRQ_SHARED,
+};
+
+/** enum acpi_irq_wake - indicates whether this interrupt can wake the device */
+enum acpi_irq_wake {
+	ACPI_IRQ_NO_WAKE,
+	ACPI_IRQ_WAKE,
+};
+
+/**
+ * struct acpi_irq - representation of an ACPI interrupt
+ *
+ * @pin: ACPI pin that is monitored for the interrupt
+ * @mode: Edge/level triggering
+ * @polarity: Interrupt polarity
+ * @shared: Whether interrupt is shared or not
+ * @wake: Whether interrupt can wake the device from sleep
+ */
+struct acpi_irq {
+	unsigned int pin;
+	enum acpi_irq_mode mode;
+	enum acpi_irq_polarity polarity;
+	enum acpi_irq_shared shared;
+	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
+ * @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];
+
+	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 Descriptors for Serial Bus interfaces */
+#define ACPI_SERIAL_BUS_TYPE_I2C		1
+#define ACPI_SERIAL_BUS_TYPE_SPI		2
+#define ACPI_I2C_SERIAL_BUS_REVISION_ID		1 /* TODO: upgrade to 2 */
+#define ACPI_I2C_TYPE_SPECIFIC_REVISION_ID	1
+#define ACPI_SPI_SERIAL_BUS_REVISION_ID		1
+#define ACPI_SPI_TYPE_SPECIFIC_REVISION_ID	1
+
+/**
+ * struct acpi_gpio - representation of an ACPI I2C device
+ *
+ * @address: 7-bit or 10-bit I2C address
+ * @mode_10bit: Which address size is used
+ * @speed: Bus speed in Hz
+ * @resource: Resource name for the I2C controller
+ */
+struct acpi_i2c {
+	u16 address;
+	enum i2c_address_mode mode_10bit;
+	enum i2c_speed_rate speed;
+	const char *resource;
+};
+
+/**
+ * struct acpi_spi - representation of an ACPI SPI device
+ *
+ * @device_select: Chip select used by this device (typically 0)
+ * @device_select_polarity: Polarity for the device
+ * @wire_mode: Number of wires used for SPI
+ * @speed: Bus speed in Hz
+ * @data_bit_length: Word length for SPI (typically 8)
+ * @clock_phase: Clock phase to capture data
+ * @clock_polarity: Bus polarity
+ * @resource: Resource name for the SPI controller
+ */
+struct acpi_spi {
+	u16 device_select;
+	enum spi_polarity device_select_polarity;
+	enum spi_wire_mode wire_mode;
+	unsigned int speed;
+	u8 data_bit_length;
+	enum spi_clock_phase clock_phase;
+	enum spi_polarity clock_polarity;
+	const char *resource;
+};
+
+/**
+ * struct acpi_power_res_params - power on/off sequence information
+ *
+ * This provides GPIOs and timing information for powering a device on and off.
+ * This can be applied to any device that has power control, so is fairly
+ * generic.
+ *
+ * @reset_gpio: GPIO used to take device out of reset or to put it into reset
+ * @reset_delay_ms: Delay to be inserted after device is taken out of reset
+ *	(_ON method delay)
+ * @reset_off_delay_ms: Delay to be inserted after device is put into reset
+ *	(_OFF method delay)
+ * @enable_gpio: GPIO used to enable device
+ * @enable_delay_ms: Delay to be inserted after device is enabled
+ * @enable_off_delay_ms: Delay to be inserted after device is disabled
+ *	(_OFF method delay)
+ * @stop_gpio: GPIO used to stop operation of device
+ * @stop_delay_ms: Delay to be inserted after disabling stop (_ON method delay)
+ * @stop_off_delay_ms: Delay to be inserted after enabling stop.
+ *	(_OFF method delay)
+ */
+struct acpi_power_res_params {
+	struct acpi_gpio *reset_gpio;
+	unsigned int reset_delay_ms;
+	unsigned int reset_off_delay_ms;
+	struct acpi_gpio *enable_gpio;
+	unsigned int enable_delay_ms;
+	unsigned int enable_off_delay_ms;
+	struct acpi_gpio *stop_gpio;
+	unsigned int stop_delay_ms;
+	unsigned int stop_off_delay_ms;
+};
+
+/**
+ * struct acpi_dp - ACPI device properties
+ *
+ * Writing Device Properties objects via _DSD
+ *
+ * This provides a structure to handle nested device-specific data which ends
+ * up in a _DSD table.
+ *
+ * https://www.kernel.org/doc/html/latest/firmware-guide/acpi/DSD-properties-rules.html
+ * https://uefi.org/sites/default/files/resources/_DSD-device-properties-UUID.pdf
+ * https://uefi.org/sites/default/files/resources/_DSD-hierarchical-data-extension-UUID-v1.1.pdf
+ *
+ * The Device Property Hierarchy can be multiple levels deep with multiple
+ * children possible in each level.  In order to support this flexibility
+ * the device property hierarchy must be built up before being written out.
+ *
+ * For example:
+ *
+ * // Child table with string and integer
+ * struct acpi_dp *child = acpi_dp_new_table("CHLD");
+ * acpi_dp_add_string(child, "childstring", "CHILD");
+ * acpi_dp_add_integer(child, "childint", 100);
+ *
+ * // _DSD table with integer and gpio and child pointer
+ * struct acpi_dp *dsd = acpi_dp_new_table("_DSD");
+ * acpi_dp_add_integer(dsd, "number1", 1);
+ * acpi_dp_add_gpio(dsd, "gpio", "\_SB.PCI0.GPIO", 0, 0, 1);
+ * acpi_dp_add_child(dsd, "child", child);
+ *
+ * // Write entries into SSDT and clean up resources
+ * acpi_dp_write(dsd);
+ *
+ * Name(_DSD, Package() {
+ *   ToUUID("daffd814-6eba-4d8c-8a91-bc9bbf4aa301")
+ *   Package() {
+ *     Package() { "gpio", Package() { \_SB.PCI0.GPIO, 0, 0, 0 } }
+ *     Package() { "number1", 1 }
+ *   }
+ *   ToUUID("dbb8e3e6-5886-4ba6-8795-1319f52a966b")
+ *   Package() {
+ *     Package() { "child", CHLD }
+ *   }
+ * }
+ * Name(CHLD, Package() {
+ *   ToUUID("daffd814-6eba-4d8c-8a91-bc9bbf4aa301")
+ *   Package() {
+ *     Package() { "childstring", "CHILD" }
+ *     Package() { "childint", 100 }
+ *   }
+ * }
+ *
+ * @type: Table type
+ * @name: Name of object, typically _DSD but could be CHLD for a child object
+ * @next: Next object in list (next array element or next sibling)
+ * @child: Pointer to first child, if @type == ACPI_DP_TYPE_CHILD, else NULL
+ * @array: First array element, if @type == ACPI_DP_TYPE_ARRAY, else NULL
+ * @integer: Integer value of the property, if @type == ACPI_DP_TYPE_INTEGER
+ * @string: String value of the property, if @type == ACPI_DP_TYPE_STRING;
+ *	child name if @type == ACPI_DP_TYPE_CHILD;
+ *	reference name if @type == ACPI_DP_TYPE_REFERENCE;
+ */
+struct acpi_dp {
+	enum acpi_dp_type type;
+	const char *name;
+	struct acpi_dp *next;
+	union {
+		struct acpi_dp *child;
+		struct acpi_dp *array;
+	};
+	union {
+		u64 integer;
+		const char *string;
+	};
+};
+
+/**
+ * acpi_dp_new_table() - Start a new Device Property table
+ *
+ * @ref: ACPI reference (e.g. "_DSD")
+ * @return pointer to table, or NULL if out of memory
+ */
+struct acpi_dp *acpi_dp_new_table(const char *ref);
+
+/**
+ * acpi_dp_add_integer() - Add integer Device Property
+ *
+ * A new node is added to the end of the property list of @dp
+ *
+ * @dp: Table to add this property to
+ * @name: Name of property
+ * @value: Integer value
+ * @return pointer to new node, or NULL if out of memory
+ */
+struct acpi_dp *acpi_dp_add_integer(struct acpi_dp *dp, const char *name,
+				    u64 value);
+
+/**
+ * acpi_dp_add_string() - Add string Device Property
+ *
+ * A new node is added to the end of the property list of @dp
+ *
+ * @dp: Table to add this property to
+ * @name: Name of property
+ * @string: String value
+ * @return pointer to new node, or NULL if out of memory
+ */
+struct acpi_dp *acpi_dp_add_string(struct acpi_dp *dp, const char *name,
+				   const char *string);
+
+/**
+ * acpi_dp_add_reference() - Add reference Device Property
+ *
+ * A new node is added to the end of the property list of @dp
+ *
+ * @dp: Table to add this property to
+ * @name: Name of property
+ * @reference: Reference value
+ * @return pointer to new node, or NULL if out of memory
+ */
+struct acpi_dp *acpi_dp_add_reference(struct acpi_dp *dp, const char *name,
+				      const char *reference);
+
+/**
+ * acpi_dp_add_array() - Add array Device Property
+ *
+ * A new node is added to the end of the property list of @dp, with the array
+ * attached to that.
+ *
+ * @dp: Table to add this property to
+ * @name: Name of property
+ * @return pointer to new node, or NULL if out of memory
+ */
+struct acpi_dp *acpi_dp_add_array(struct acpi_dp *dp, struct acpi_dp *array);
+
+/**
+ * acpi_dp_add_integer_array() - Add an array of integers
+ *
+ * A new node is added to the end of the property list of @dp, with the array
+ * attached to that. Each element of the array becomes a new node.
+ *
+ * @dp: Table to add this property to
+ * @name: Name of property
+ * @return pointer to new array node, or NULL if out of memory
+ */
+struct acpi_dp *acpi_dp_add_integer_array(struct acpi_dp *dp, const char *name,
+					  u64 *array, int len);
+
+/**
+ * acpi_dp_add_gpio() - Add a GPIO binding Device Property
+ *
+ * A new node is added to the end of the property list of @dp, with the
+ * GPIO properties added to the the new node
+ *
+ * @dp: Table to add this property to
+ * @name: Name of property
+ * @ref: Reference of the device that has _CRS containing GpioIO()/GpioInt()
+ * @index: Index of the GPIO resource in _CRS starting from zero
+ * @pin: Pin in the GPIO resource, typically zero
+ * @active_low: true if pin is active low
+ * @return pointer to new node, or NULL if out of memory
+ */
+struct acpi_dp *acpi_dp_add_gpio(struct acpi_dp *dp, const char *name,
+				 const char *ref, int index, int pin,
+				 bool active_low);
+
+/**
+ * acpi_dp_add_child() - Add a child table of Device Properties
+ *
+ * A new node is added as a child of @dp
+ *
+ * @dp: Table to add this child to
+ * @name: Name of child
+ * @child: Child node to add
+ * @return pointer to new array node, or NULL if out of memory
+ */
+struct acpi_dp *acpi_dp_add_child(struct acpi_dp *dp, const char *name,
+				  struct acpi_dp *child);
+
+/**
+ * acpi_dp_add_property_list() - Add a list of of Device Properties
+ *
+ * This adds a list of properties to @dp. Any properties without a name or of
+ * type ACPI_DP_TYPE_UNKNOWN are ignored.
+ *
+ * @dp: Table to add properties to
+ * @property_list: List of properties to add
+ * @property_count: Number of properties in the list
+ * @return number of properties added
+ */
+size_t acpi_dp_add_property_list(struct acpi_dp *dp,
+				 const struct acpi_dp *property_list,
+				 size_t property_count);
+
+/**
+ * acpi_dp_write() - Write Device Property hierarchy and clean up resources
+ *
+ * This writes the table using acpigen and then frees it
+ *
+ * @table: Table to write
+ * @return 0 if OK, -ve on error
+ */
+int acpi_dp_write(struct acpi_ctx *ctx, struct acpi_dp *table);
+
+/**
+ * acpi_device_write_i2c_dev() - Write an I2C device to ACPI, including
+ * information ACPI needs to use it.
+ *
+ * This writes a serial bus descriptor for the I2C device so that ACPI can
+ */
+int acpi_device_write_i2c_dev(struct acpi_ctx *ctx, const struct udevice *dev);
+
+/**
+ * struct acpi_i2c_priv - Information read from device tree
+ *
+ * This is used by devices which want to specify various pieces of ACPI
+ * information, including power control. It allows a generic function to
+ * generate the information for ACPI, based on device-tree properties.
+ *
+ * @disable_gpio_export_in_crs: Don't export GPIOs in the CRS
+ * @reset_gpio: GPIO used to assert reset to the device
+ * @enable_gpio: GPIO used to enable the device
+ * @stop_gpio: GPIO used to stop the device
+ * @irq_gpio: GPIO used for interrupt (if @irq is not used)
+ * @irq: IRQ used for interrupt (if @irq_gpio is not used)
+ * @hid: _HID value for device (required)
+ * @uid: _UID value for device
+ * @desc: _DDN value for device
+ * @wake: Wake event, e.g. GPE0_DW1_15; 0 if none
+ * @property_count: Number of other DSD properties (currently always 0)
+ * @probed: true set set 'linux,probed' property
+ * @compat_string: Device tree compatible string to report through ACPI
+ * @has_power_resource: true if this device has a power resource
+ * @reset_delay_ms: Delay after de-asserting reset, in ms
+ * @reset_off_delay_ms: Delay after asserting reset (during power off)
+ * @enable_delay_ms: Delay after asserting enable
+ * @enable_off_delay_ms: Delay after de-asserting enable (during power off)
+ * @stop_delay_ms: Delay after de-aserting stop
+ * @stop_off_delay_ms: Delay after asserting stop (during power off)
+ * @hid_desc_reg_offset: HID register offset (for Human Interface Devices)
+ */
+struct acpi_i2c_priv {
+	bool disable_gpio_export_in_crs;
+	struct gpio_desc reset_gpio;
+	struct gpio_desc enable_gpio;
+	struct gpio_desc irq_gpio;
+	struct gpio_desc stop_gpio;
+	struct irq irq;
+	const char *hid;
+	u32 uid;
+	const char *desc;
+	u32 wake;
+	u32 property_count;
+	bool probed;
+	const char *compat_string;
+	bool has_power_resource;
+	u32 reset_delay_ms;
+	u32 reset_off_delay_ms;
+	u32 enable_delay_ms;
+	u32 enable_off_delay_ms;
+	u32 stop_delay_ms;
+	u32 stop_off_delay_ms;
+	u32 hid_desc_reg_offset;
+};
+
+/**
+ * I2C Human-Interface Devices configuration
+ *
+ * @hid_desc_reg_offset: HID register offset
+ */
+struct dsm_i2c_hid_config {
+	u8 hid_desc_reg_offset;
+};
+
+/**
+ * acpi_device_write_gpio() - Write GpioIo() or GpioInt() descriptor
+ *
+ * @gpio: GPIO information to write
+ * @return 0 if OK, -ve on error
+ */
+int acpi_device_write_gpio(struct acpi_ctx *ctx, const struct acpi_gpio *gpio);
+
+/*
+ * acpi_device_add_power_res() - Add a basic PowerResource block for a device
+ *
+ * This includes GPIOs to control enable, reset and stop operation of the
+ * device. Each GPIO is optional, but at least one must be provided.
+ *
+ * Reset - Put the device into / take the device out of reset.
+ * Enable - Enable / disable power to device.
+ * Stop - Stop / start operation of device.
+ *
+ * @return 0 if OK, -ve if at least one GPIO is not provided
+ */
+int acpi_device_add_power_res(struct acpi_ctx *ctx,
+			      const struct acpi_power_res_params *params);
+
+/**
+ * gpio_get_acpi() - Convert a GPIO description into an ACPI GPIO
+ *
+ * At present this is fairly limited. It only supports ACPI_GPIO_TYPE_IO and
+ * has hard-coded settings for type, pull, IO restrict and polarity. These
+ * could come from pinctrl potentially.
+ *
+ * @desc: GPIO description to convert
+ * @gpio: Place to put ACPI GPIO information
+ * @return 0 if OK, -ENOENT if @desc is invalid
+ */
+int gpio_get_acpi(const struct gpio_desc *desc, struct acpi_gpio *gpio);
+
+/**
+ * acpi_device_write_dsm_i2c_hid() - Write a device-specific method for HID
+ *
+ * This writes a DSM for an I2C Human-Interface Device based on the config
+ * provided
+ *
+ * @config: Config information to write
+ */
+void acpi_device_write_dsm_i2c_hid(struct acpi_ctx *ctx,
+				   struct dsm_i2c_hid_config *config);
+
+/**
+ * acpi_dp_ofnode_copy_int() - Copy a property from device tree to DP
+ *
+ * This copies an integer property from the device tree to the ACPI DP table.
+ *
+ * @dev: Device to copy from
+ * @dp: DP to copy to
+ * @prop: Property name to copy
+ * @return 0 if OK, -ve on error
+ */
+int acpi_dp_ofnode_copy_int(ofnode node, struct acpi_dp *dp, const char *prop);
+
+/**
+ * acpi_dp_dev_copy_str() - Copy a property from device tree to DP
+ *
+ * This copies a string property from the device tree to the ACPI DP table.
+ *
+ * @dev: Device to copy from
+ * @dp: DP to copy to
+ * @prop: Property name to copy
+ * @return 0 if OK, -ve on error
+ */
+int acpi_dp_ofnode_copy_str(ofnode node, struct acpi_dp *dp, const char *prop);
+
+/**
+ * acpi_dp_dev_copy_int() - Copy a property from device tree to DP
+ *
+ * This copies an integer property from the device tree to the ACPI DP table.
+ *
+ * @dev: Device to copy from
+ * @dp: DP to copy to
+ * @prop: Property name to copy
+ * @return 0 if OK, -ve on error
+ */
+int acpi_dp_dev_copy_int(const struct udevice *dev, struct acpi_dp *dp,
+			 const char *prop);
+
+/**
+ * acpi_dp_dev_copy_str() - Copy a property from device tree to DP
+ *
+ * This copies a string property from the device tree to the ACPI DP table.
+ *
+ * @dev: Device to copy from
+ * @dp: DP to copy to
+ * @prop: Property name to copy
+ * @return 0 if OK, -ve on error
+ */
+int acpi_dp_dev_copy_str(const struct udevice *dev, struct acpi_dp *dp,
+			 const char *prop);
+
+int acpi_device_get_name(const struct udevice *dev, char *out_name);
+
+#endif
diff --git a/lib/acpi/acpi_device.c b/lib/acpi/acpi_device.c
new file mode 100644
index 0000000000..145de90677
--- /dev/null
+++ b/lib/acpi/acpi_device.c
@@ -0,0 +1,1094 @@ 
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Generation of tables for particular device types
+ *
+ * Copyright 2019 Google LLC
+ * Mostly taken from coreboot file of the same name
+ */
+
+#include <common.h>
+#include <acpi_device.h>
+#include <acpigen.h>
+#include <dm.h>
+#include <irq.h>
+#include <malloc.h>
+#include <usb.h>
+#include <asm-generic/gpio.h>
+#include <dm/acpi.h>
+
+#define ACPI_DP_UUID		"daffd814-6eba-4d8c-8a91-bc9bbf4aa301"
+#define ACPI_DP_CHILD_UUID	"dbb8e3e6-5886-4ba6-8795-1319f52a966b"
+#define ACPI_DSM_I2C_HID_UUID	"3cdff6f7-4267-4555-ad05-b30a3d8938de"
+
+/**
+ * acpi_device_write_zero_len() - Write a placeholder word value
+ *
+ * @return pointer to the zero word (for fixing up later)
+ */
+static void *acpi_device_write_zero_len(struct acpi_ctx *ctx)
+{
+	char *p = acpigen_get_current(ctx);
+
+	acpigen_emit_word(ctx, 0);
+
+	return p;
+}
+
+/**
+ * acpi_device_fill_from_len() - Fill in a length value
+ *
+ * This calculated the number of bytes since the provided @start and writes it
+ * to @ptr, which was previous returned by acpi_device_write_zero_len().
+ *
+ * @ptr: Word to update
+ * @start: Start address to count from to calculated the length
+ */
+static void acpi_device_fill_from_len(struct acpi_ctx *ctx, char *ptr,
+				      char *start)
+{
+	u16 len = acpigen_get_current(ctx) - start;
+
+	ptr[0] = len & 0xff;
+	ptr[1] = (len >> 8) & 0xff;
+}
+
+/**
+ * acpi_device_fill_len() - Fill in a length value, excluding the length itself
+ *
+ * Fill in the length field with the value calculated from after the 16bit
+ * field to acpigen current. This is useful since the length value does not
+ * include the length field itself.
+ *
+ * This calls acpi_device_fill_from_len() passing @ptr + 2 as @start
+ *
+ * @ptr: Word to update.
+ */
+static void acpi_device_fill_len(struct acpi_ctx *ctx, void *ptr)
+{
+	acpi_device_fill_from_len(ctx, ptr, ptr + sizeof(u16));
+}
+
+int acpi_device_name(const struct udevice *dev, char *name)
+{
+	int ret;
+
+	ret = acpi_get_name(dev, name);
+	if (ret)
+		return log_msg_ret("name", ret);
+
+	return 0;
+}
+
+/**
+ * acpi_device_path_fill() - Find the root device and build a path from there
+ *
+ * This recursively reaches back to the root device and progressively adds path
+ * elements until the device is reached.
+ *
+ * @dev: Device to return path of
+ * @buf: Buffer to hold the path
+ * @buf_len: Length of buffer
+ * @cur: Current position in the buffer
+ * @return new position in buffer after adding @dev, or -ve on error
+ */
+static int acpi_device_path_fill(const struct udevice *dev, char *buf,
+				 size_t buf_len, int cur)
+{
+	char name[ACPI_NAME_MAX];
+	int next = 0;
+	int ret;
+
+	ret = acpi_device_name(dev, name);
+	if (ret)
+		return ret;
+
+	/*
+	 * Make sure this name segment will fit, including the path segment
+	 * separator and possible NUL terminator if this is the last segment.
+	 */
+	if (!dev || (cur + strlen(name) + 2) > buf_len)
+		return cur;
+
+	/* Walk up the tree to the root device */
+	if (dev_get_parent(dev)) {
+		next = acpi_device_path_fill(dev_get_parent(dev), buf, buf_len,
+					     cur);
+		if (next < 0)
+			return next;
+	}
+
+	/* Fill in the path from the root device */
+	next += snprintf(buf + next, buf_len - next, "%s%s",
+			 dev_get_parent(dev) && *name ? "." : "", name);
+
+	return next;
+}
+
+int acpi_device_path(const struct udevice *dev, char *buf, int maxlen)
+{
+	int ret;
+
+	ret = acpi_device_path_fill(dev, buf, maxlen, 0);
+	if (ret < 0)
+		return ret;
+
+	return 0;
+}
+
+int acpi_device_scope(const struct udevice *dev, char *scope, int maxlen)
+{
+	int ret;
+
+	if (!dev_get_parent(dev))
+		return log_msg_ret("noparent", -EINVAL);
+
+	ret = acpi_device_path_fill(dev_get_parent(dev), scope, maxlen, 0);
+	if (ret < 0)
+		return log_msg_ret("fill", ret);
+
+	return 0;
+}
+
+int acpi_device_status(const struct udevice *dev)
+{
+	return ACPI_STATUS_DEVICE_ALL_ON;
+}
+
+/* ACPI 6.1 section 6.4.3.8.1 - GPIO Interrupt or I/O */
+int acpi_device_write_gpio(struct acpi_ctx *ctx, const struct acpi_gpio *gpio)
+{
+	void *start, *desc_length;
+	void *pin_table_offset, *vendor_data_offset, *resource_offset;
+	u16 flags = 0;
+	int pin;
+
+	if (!gpio || gpio->type > ACPI_GPIO_TYPE_IO)
+		return -EINVAL;
+
+	start = acpigen_get_current(ctx);
+
+	/* Byte 0: Descriptor Type */
+	acpigen_emit_byte(ctx, ACPI_DESCRIPTOR_GPIO);
+
+	/* Byte 1-2: Length (fill in later) */
+	desc_length = acpi_device_write_zero_len(ctx);
+
+	/* Byte 3: Revision ID */
+	acpigen_emit_byte(ctx, ACPI_GPIO_REVISION_ID);
+
+	/* Byte 4: GpioIo or GpioInt */
+	acpigen_emit_byte(ctx, gpio->type);
+
+	/*
+	 * Byte 5-6: General Flags
+	 *   [15:1]: 0 => Reserved
+	 *      [0]: 1 => ResourceConsumer
+	 */
+	acpigen_emit_word(ctx, 1 << 0);
+
+	switch (gpio->type) {
+	case ACPI_GPIO_TYPE_INTERRUPT:
+		/*
+		 * Byte 7-8: GPIO Interrupt Flags
+		 *   [15:5]: 0 => Reserved
+		 *      [4]: Wake     (0=NO_WAKE   1=WAKE)
+		 *      [3]: Sharing  (0=EXCLUSIVE 1=SHARED)
+		 *    [2:1]: Polarity (0=HIGH      1=LOW     2=BOTH)
+		 *      [0]: Mode     (0=LEVEL     1=EDGE)
+		 */
+		if (gpio->irq.mode == ACPI_IRQ_EDGE_TRIGGERED)
+			flags |= 1 << 0;
+		if (gpio->irq.shared == ACPI_IRQ_SHARED)
+			flags |= 1 << 3;
+		if (gpio->irq.wake == ACPI_IRQ_WAKE)
+			flags |= 1 << 4;
+
+		switch (gpio->irq.polarity) {
+		case ACPI_IRQ_ACTIVE_HIGH:
+			flags |= 0 << 1;
+			break;
+		case ACPI_IRQ_ACTIVE_LOW:
+			flags |= 1 << 1;
+			break;
+		case ACPI_IRQ_ACTIVE_BOTH:
+			flags |= 2 << 1;
+			break;
+		}
+		break;
+
+	case ACPI_GPIO_TYPE_IO:
+		/*
+		 * Byte 7-8: GPIO IO Flags
+		 *   [15:4]: 0 => Reserved
+		 *      [3]: Sharing  (0=EXCLUSIVE 1=SHARED)
+		 *      [2]: 0 => Reserved
+		 *    [1:0]: IO Restriction
+		 *           0 => IoRestrictionNone
+		 *           1 => IoRestrictionInputOnly
+		 *           2 => IoRestrictionOutputOnly
+		 *           3 => IoRestrictionNoneAndPreserve
+		 */
+		flags |= gpio->io_restrict & 3;
+		if (gpio->io_shared)
+			flags |= 1 << 3;
+		break;
+	}
+	acpigen_emit_word(ctx, flags);
+
+	/*
+	 * Byte 9: Pin Configuration
+	 *  0x01 => Default (no configuration applied)
+	 *  0x02 => Pull-up
+	 *  0x03 => Pull-down
+	 *  0x04-0x7F => Reserved
+	 *  0x80-0xff => Vendor defined
+	 */
+	acpigen_emit_byte(ctx, gpio->pull);
+
+	/* Byte 10-11: Output Drive Strength in 1/100 mA */
+	acpigen_emit_word(ctx, gpio->output_drive_strength);
+
+	/* Byte 12-13: Debounce Timeout in 1/100 ms */
+	acpigen_emit_word(ctx, gpio->interrupt_debounce_timeout);
+
+	/* Byte 14-15: Pin Table Offset, relative to start */
+	pin_table_offset = acpi_device_write_zero_len(ctx);
+
+	/* Byte 16: Reserved */
+	acpigen_emit_byte(ctx, 0);
+
+	/* Byte 17-18: Resource Source Name Offset, relative to start */
+	resource_offset = acpi_device_write_zero_len(ctx);
+
+	/* Byte 19-20: Vendor Data Offset, relative to start */
+	vendor_data_offset = acpi_device_write_zero_len(ctx);
+
+	/* Byte 21-22: Vendor Data Length */
+	acpigen_emit_word(ctx, 0);
+
+	/* Fill in Pin Table Offset */
+	acpi_device_fill_from_len(ctx, pin_table_offset, start);
+
+	/* Pin Table, one word for each pin */
+	for (pin = 0; pin < gpio->pin_count; pin++)
+		acpigen_emit_word(ctx, gpio->pins[pin]);
+
+	/* Fill in Resource Source Name Offset */
+	acpi_device_fill_from_len(ctx, resource_offset, start);
+
+	/* Resource Source Name String */
+	acpigen_emit_string(ctx, gpio->resource);
+
+	/* Fill in Vendor Data Offset */
+	acpi_device_fill_from_len(ctx, vendor_data_offset, start);
+
+	/* Fill in GPIO Descriptor Length (account for len word) */
+	acpi_device_fill_len(ctx, desc_length);
+
+	return 0;
+}
+
+/* ACPI 6.1 section 6.4.3.8.2.1 - I2cSerialBus() */
+static void acpi_device_write_i2c(struct acpi_ctx *ctx,
+				  const struct acpi_i2c *i2c)
+{
+	void *desc_length, *type_length;
+
+	/* Byte 0: Descriptor Type */
+	acpigen_emit_byte(ctx, ACPI_DESCRIPTOR_SERIAL_BUS);
+
+	/* Byte 1+2: Length (filled in later) */
+	desc_length = acpi_device_write_zero_len(ctx);
+
+	/* Byte 3: Revision ID */
+	acpigen_emit_byte(ctx, ACPI_I2C_SERIAL_BUS_REVISION_ID);
+
+	/* Byte 4: Resource Source Index is Reserved */
+	acpigen_emit_byte(ctx, 0);
+
+	/* Byte 5: Serial Bus Type is I2C */
+	acpigen_emit_byte(ctx, ACPI_SERIAL_BUS_TYPE_I2C);
+
+	/*
+	 * Byte 6: Flags
+	 *  [7:2]: 0 => Reserved
+	 *    [1]: 1 => ResourceConsumer
+	 *    [0]: 0 => ControllerInitiated
+	 */
+	acpigen_emit_byte(ctx, 1 << 1);
+
+	/*
+	 * Byte 7-8: Type Specific Flags
+	 *   [15:1]: 0 => Reserved
+	 *      [0]: 0 => 7bit, 1 => 10bit
+	 */
+	acpigen_emit_word(ctx, i2c->mode_10bit);
+
+	/* Byte 9: Type Specific Revision ID */
+	acpigen_emit_byte(ctx, ACPI_I2C_TYPE_SPECIFIC_REVISION_ID);
+
+	/* Byte 10-11: I2C Type Data Length */
+	type_length = acpi_device_write_zero_len(ctx);
+
+	/* Byte 12-15: I2C Bus Speed */
+	acpigen_emit_dword(ctx, i2c->speed);
+
+	/* Byte 16-17: I2C Slave Address */
+	acpigen_emit_word(ctx, i2c->address);
+
+	/* Fill in Type Data Length */
+	acpi_device_fill_len(ctx, type_length);
+
+	/* Byte 18+: ResourceSource */
+	acpigen_emit_string(ctx, i2c->resource);
+
+	/* Fill in I2C Descriptor Length */
+	acpi_device_fill_len(ctx, desc_length);
+}
+
+/* ACPI 6.1 section 6.4.3.8.2.2 - SpiSerialBus() */
+void acpi_device_write_spi(struct acpi_ctx *ctx, const struct acpi_spi *spi)
+{
+	void *desc_length, *type_length;
+	u16 flags = 0;
+
+	/* Byte 0: Descriptor Type */
+	acpigen_emit_byte(ctx, ACPI_DESCRIPTOR_SERIAL_BUS);
+
+	/* Byte 1+2: Length (filled in later) */
+	desc_length = acpi_device_write_zero_len(ctx);
+
+	/* Byte 3: Revision ID */
+	acpigen_emit_byte(ctx, ACPI_SPI_SERIAL_BUS_REVISION_ID);
+
+	/* Byte 4: Resource Source Index is Reserved */
+	acpigen_emit_byte(ctx, 0);
+
+	/* Byte 5: Serial Bus Type is SPI */
+	acpigen_emit_byte(ctx, ACPI_SERIAL_BUS_TYPE_SPI);
+
+	/*
+	 * Byte 6: Flags
+	 *  [7:2]: 0 => Reserved
+	 *    [1]: 1 => ResourceConsumer
+	 *    [0]: 0 => ControllerInitiated
+	 */
+	acpigen_emit_byte(ctx, 1 << 1);
+
+	/*
+	 * Byte 7-8: Type Specific Flags
+	 *   [15:2]: 0 => Reserveda
+	 *      [1]: 0 => ActiveLow, 1 => ActiveHigh
+	 *      [0]: 0 => FourWire, 1 => ThreeWire
+	 */
+	if (spi->wire_mode == SPI_3_WIRE_MODE)
+		flags |= 1 << 0;
+	if (spi->device_select_polarity == SPI_POLARITY_HIGH)
+		flags |= 1 << 1;
+	acpigen_emit_word(ctx, flags);
+
+	/* Byte 9: Type Specific Revision ID */
+	acpigen_emit_byte(ctx, ACPI_SPI_TYPE_SPECIFIC_REVISION_ID);
+
+	/* Byte 10-11: SPI Type Data Length */
+	type_length = acpi_device_write_zero_len(ctx);
+
+	/* Byte 12-15: Connection Speed */
+	acpigen_emit_dword(ctx, spi->speed);
+
+	/* Byte 16: Data Bit Length */
+	acpigen_emit_byte(ctx, spi->data_bit_length);
+
+	/* Byte 17: Clock Phase */
+	acpigen_emit_byte(ctx, spi->clock_phase);
+
+	/* Byte 18: Clock Polarity */
+	acpigen_emit_byte(ctx, spi->clock_polarity);
+
+	/* Byte 19-20: Device Selection */
+	acpigen_emit_word(ctx, spi->device_select);
+
+	/* Fill in Type Data Length */
+	acpi_device_fill_len(ctx, type_length);
+
+	/* Byte 21+: ResourceSource String */
+	acpigen_emit_string(ctx, spi->resource);
+
+	/* Fill in SPI Descriptor Length */
+	acpi_device_fill_len(ctx, desc_length);
+}
+
+/* PowerResource() with Enable and/or Reset control */
+int acpi_device_add_power_res(struct acpi_ctx *ctx,
+			      const struct acpi_power_res_params *params)
+{
+	static const char *const power_res_dev_states[] = { "_PR0", "_PR3" };
+	unsigned int reset_gpio = params->reset_gpio->pins[0];
+	unsigned int enable_gpio = params->enable_gpio->pins[0];
+	unsigned int stop_gpio = params->stop_gpio->pins[0];
+	int ret;
+
+	if (!reset_gpio && !enable_gpio && !stop_gpio)
+		return -EINVAL;
+
+	/* PowerResource (PRIC, 0, 0) */
+	acpigen_write_power_res(ctx, "PRIC", 0, 0, power_res_dev_states,
+				ARRAY_SIZE(power_res_dev_states));
+
+	/* Method (_STA, 0, NotSerialized) { Return (0x1) } */
+	acpigen_write_sta(ctx, 0x1);
+
+	/* Method (_ON, 0, Serialized) */
+	acpigen_write_method_serialized(ctx, "_ON", 0);
+	if (reset_gpio) {
+		ret = acpigen_enable_tx_gpio(ctx, params->reset_gpio);
+		if (ret)
+			return log_msg_ret("reset1", ret);
+	}
+	if (enable_gpio) {
+		ret = acpigen_enable_tx_gpio(ctx, params->enable_gpio);
+		if (ret)
+			return log_msg_ret("enable1", ret);
+		if (params->enable_delay_ms)
+			acpigen_write_sleep(ctx, params->enable_delay_ms);
+	}
+	if (reset_gpio) {
+		ret = acpigen_disable_tx_gpio(ctx, params->reset_gpio);
+		if (ret)
+			return log_msg_ret("reset2", ret);
+		if (params->reset_delay_ms)
+			acpigen_write_sleep(ctx, params->reset_delay_ms);
+	}
+	if (stop_gpio) {
+		ret = acpigen_disable_tx_gpio(ctx, params->stop_gpio);
+		if (ret)
+			return log_msg_ret("stop1", ret);
+		if (params->stop_delay_ms)
+			acpigen_write_sleep(ctx, params->stop_delay_ms);
+	}
+	acpigen_pop_len(ctx);		/* _ON method */
+
+	/* Method (_OFF, 0, Serialized) */
+	acpigen_write_method_serialized(ctx, "_OFF", 0);
+	if (stop_gpio) {
+		ret = acpigen_enable_tx_gpio(ctx, params->stop_gpio);
+		if (ret)
+			return log_msg_ret("stop2", ret);
+		if (params->stop_off_delay_ms)
+			acpigen_write_sleep(ctx, params->stop_off_delay_ms);
+	}
+	if (reset_gpio) {
+		ret = acpigen_enable_tx_gpio(ctx, params->reset_gpio);
+		if (ret)
+			return log_msg_ret("reset3", ret);
+		if (params->reset_off_delay_ms)
+			acpigen_write_sleep(ctx, params->reset_off_delay_ms);
+	}
+	if (enable_gpio) {
+		ret = acpigen_disable_tx_gpio(ctx, params->enable_gpio);
+		if (ret)
+			return log_msg_ret("enable2", ret);
+		if (params->enable_off_delay_ms)
+			acpigen_write_sleep(ctx, params->enable_off_delay_ms);
+	}
+	acpigen_pop_len(ctx);		/* _OFF method */
+
+	acpigen_pop_len(ctx);		/* PowerResource PRIC */
+
+	return 0;
+}
+
+static void acpi_dp_write_array(struct acpi_ctx *ctx,
+				const struct acpi_dp *array);
+
+static void acpi_dp_write_value(struct acpi_ctx *ctx,
+				const struct acpi_dp *prop)
+{
+	switch (prop->type) {
+	case ACPI_DP_TYPE_INTEGER:
+		acpigen_write_integer(ctx, prop->integer);
+		break;
+	case ACPI_DP_TYPE_STRING:
+	case ACPI_DP_TYPE_CHILD:
+		acpigen_write_string(ctx, prop->string);
+		break;
+	case ACPI_DP_TYPE_REFERENCE:
+		acpigen_emit_namestring(ctx, prop->string);
+		break;
+	case ACPI_DP_TYPE_ARRAY:
+		acpi_dp_write_array(ctx, prop->array);
+		break;
+	default:
+		break;
+	}
+}
+
+/* Package (2) { "prop->name", VALUE } */
+static void acpi_dp_write_property(struct acpi_ctx *ctx,
+				   const struct acpi_dp *prop)
+{
+	acpigen_write_package(ctx, 2);
+	acpigen_write_string(ctx, prop->name);
+	acpi_dp_write_value(ctx, prop);
+	acpigen_pop_len(ctx);
+}
+
+/* Write array of Device Properties */
+static void acpi_dp_write_array(struct acpi_ctx *ctx,
+				const struct acpi_dp *array)
+{
+	const struct acpi_dp *dp;
+	char *pkg_count;
+
+	/* Package element count determined as it is populated */
+	pkg_count = acpigen_write_package(ctx, 0);
+
+	/*
+	 * Only acpi_dp of type DP_TYPE_TABLE is allowed to be an array.
+	 * DP_TYPE_TABLE does not have a value to be written. Thus, start
+	 * the loop from next type in the array.
+	 */
+	for (dp = array->next; dp; dp = dp->next) {
+		acpi_dp_write_value(ctx, dp);
+		(*pkg_count)++;
+	}
+
+	acpigen_pop_len(ctx);
+}
+
+static void acpi_dp_free(struct acpi_dp *dp)
+{
+	while (dp) {
+		struct acpi_dp *p = dp->next;
+
+		switch (dp->type) {
+		case ACPI_DP_TYPE_CHILD:
+			acpi_dp_free(dp->child);
+			break;
+		case ACPI_DP_TYPE_ARRAY:
+			acpi_dp_free(dp->array);
+			break;
+		default:
+			break;
+		}
+
+		free(dp);
+		dp = p;
+	}
+}
+
+int acpi_dp_write(struct acpi_ctx *ctx, struct acpi_dp *table)
+{
+	struct acpi_dp *dp, *prop;
+	char *dp_count, *prop_count = NULL;
+	int child_count = 0;
+	int ret;
+
+	if (!table || table->type != ACPI_DP_TYPE_TABLE)
+		return 0;
+
+	/* Name (name) */
+	acpigen_write_name(ctx, table->name);
+
+	/* Device Property list starts with the next entry */
+	prop = table->next;
+
+	/* Package (DP), default to assuming no properties or children */
+	dp_count = acpigen_write_package(ctx, 0);
+
+	/* Print base properties */
+	for (dp = prop; dp; dp = dp->next) {
+		if (dp->type == ACPI_DP_TYPE_CHILD) {
+			child_count++;
+		} else {
+			/*
+			 * The UUID and package is only added when
+			 * we come across the first property.  This
+			 * is to avoid creating a zero-length package
+			 * in situations where there are only children.
+			 */
+			if (!prop_count) {
+				*dp_count += 2;
+				/* ToUUID (ACPI_DP_UUID) */
+				ret = acpigen_write_uuid(ctx, ACPI_DP_UUID);
+				if (ret)
+					return log_msg_ret("touuid", ret);
+				/*
+				 * Package (PROP), element count determined as
+				 * it is populated
+				 */
+				prop_count = acpigen_write_package(ctx, 0);
+			}
+			(*prop_count)++;
+			acpi_dp_write_property(ctx, dp);
+		}
+	}
+
+	if (prop_count) {
+		/* Package (PROP) length, if a package was written */
+		acpigen_pop_len(ctx);
+	}
+
+	if (child_count) {
+		/* Update DP package count to 2 or 4 */
+		*dp_count += 2;
+		/* ToUUID (ACPI_DP_CHILD_UUID) */
+		ret = acpigen_write_uuid(ctx, ACPI_DP_CHILD_UUID);
+		if (ret)
+			return log_msg_ret("child uuid", ret);
+
+		/* Print child pointer properties */
+		acpigen_write_package(ctx, child_count);
+
+		for (dp = prop; dp; dp = dp->next)
+			if (dp->type == ACPI_DP_TYPE_CHILD)
+				acpi_dp_write_property(ctx, dp);
+		/* Package (CHILD) length */
+		acpigen_pop_len(ctx);
+	}
+
+	/* Package (DP) length */
+	acpigen_pop_len(ctx);
+
+	/* Recursively parse children into separate tables */
+	for (dp = prop; dp; dp = dp->next) {
+		if (dp->type == ACPI_DP_TYPE_CHILD) {
+			ret = acpi_dp_write(ctx, dp->child);
+			if (ret)
+				return log_msg_ret("dp child", ret);
+		}
+	}
+
+	/* Clean up */
+	acpi_dp_free(table);
+
+	return 0;
+}
+
+static struct acpi_dp *acpi_dp_new(struct acpi_dp *dp, enum acpi_dp_type type,
+				   const char *name)
+{
+	struct acpi_dp *new;
+
+	new = malloc(sizeof(struct acpi_dp));
+	if (!new)
+		return NULL;
+
+	memset(new, '\0', sizeof(*new));
+	new->type = type;
+	new->name = name;
+
+	if (dp) {
+		/* Add to end of property list */
+		while (dp->next)
+			dp = dp->next;
+		dp->next = new;
+	}
+
+	return new;
+}
+
+struct acpi_dp *acpi_dp_new_table(const char *name)
+{
+	return acpi_dp_new(NULL, ACPI_DP_TYPE_TABLE, name);
+}
+
+size_t acpi_dp_add_property_list(struct acpi_dp *dp,
+				 const struct acpi_dp *property_list,
+				 size_t property_count)
+{
+	const struct acpi_dp *prop;
+	size_t i, properties_added = 0;
+
+	if (!dp || !property_list)
+		return 0;
+
+	for (i = 0; i < property_count; i++) {
+		prop = &property_list[i];
+
+		if (prop->type == ACPI_DP_TYPE_UNKNOWN || !prop->name)
+			continue;
+
+		switch (prop->type) {
+		case ACPI_DP_TYPE_INTEGER:
+			acpi_dp_add_integer(dp, prop->name, prop->integer);
+			break;
+		case ACPI_DP_TYPE_STRING:
+			acpi_dp_add_string(dp, prop->name, prop->string);
+			break;
+		case ACPI_DP_TYPE_REFERENCE:
+			acpi_dp_add_reference(dp, prop->name, prop->string);
+			break;
+		case ACPI_DP_TYPE_ARRAY:
+			acpi_dp_add_array(dp, prop->array);
+			break;
+		case ACPI_DP_TYPE_CHILD:
+			acpi_dp_add_child(dp, prop->name, prop->child);
+			break;
+		default:
+			continue;
+		}
+
+		++properties_added;
+	}
+
+	return properties_added;
+}
+
+struct acpi_dp *acpi_dp_add_integer(struct acpi_dp *dp, const char *name,
+				    u64 value)
+{
+	struct acpi_dp *new = acpi_dp_new(dp, ACPI_DP_TYPE_INTEGER, name);
+
+	if (new)
+		new->integer = value;
+
+	return new;
+}
+
+struct acpi_dp *acpi_dp_add_string(struct acpi_dp *dp, const char *name,
+				   const char *string)
+{
+	struct acpi_dp *new = acpi_dp_new(dp, ACPI_DP_TYPE_STRING, name);
+
+	if (new)
+		new->string = string;
+
+	return new;
+}
+
+struct acpi_dp *acpi_dp_add_reference(struct acpi_dp *dp, const char *name,
+				      const char *reference)
+{
+	if (!dp)
+		return NULL;
+
+	struct acpi_dp *new = acpi_dp_new(dp, ACPI_DP_TYPE_REFERENCE, name);
+
+	if (new)
+		new->string = reference;
+
+	return new;
+}
+
+struct acpi_dp *acpi_dp_add_child(struct acpi_dp *dp, const char *name,
+				  struct acpi_dp *child)
+{
+	struct acpi_dp *new;
+
+	if (!dp || !child || child->type != ACPI_DP_TYPE_TABLE)
+		return NULL;
+
+	new = acpi_dp_new(dp, ACPI_DP_TYPE_CHILD, name);
+	if (new) {
+		new->child = child;
+		new->string = child->name;
+	}
+
+	return new;
+}
+
+struct acpi_dp *acpi_dp_add_array(struct acpi_dp *dp, struct acpi_dp *array)
+{
+	struct acpi_dp *new;
+
+	if (!dp || !array || array->type != ACPI_DP_TYPE_TABLE)
+		return NULL;
+
+	new = acpi_dp_new(dp, ACPI_DP_TYPE_ARRAY, array->name);
+	if (new)
+		new->array = array;
+
+	return new;
+}
+
+struct acpi_dp *acpi_dp_add_integer_array(struct acpi_dp *dp, const char *name,
+					  u64 *array, int len)
+{
+	struct acpi_dp *dp_array;
+	int i;
+
+	if (!dp || len <= 0)
+		return NULL;
+
+	dp_array = acpi_dp_new_table(name);
+	if (!dp_array)
+		return NULL;
+
+	for (i = 0; i < len; i++)
+		if (!acpi_dp_add_integer(dp_array, NULL, array[i]))
+			break;
+
+	acpi_dp_add_array(dp, dp_array);
+
+	return dp_array;
+}
+
+struct acpi_dp *acpi_dp_add_gpio(struct acpi_dp *dp, const char *name,
+				 const char *ref, int index, int pin,
+				 bool active_low)
+{
+	if (!dp)
+		return NULL;
+
+	struct acpi_dp *gpio = acpi_dp_new_table(name);
+
+	if (!gpio)
+		return NULL;
+
+	/* The device that has _CRS containing GpioIO()/GpioInt() */
+	acpi_dp_add_reference(gpio, NULL, ref);
+
+	/* Index of the GPIO resource in _CRS starting from zero */
+	acpi_dp_add_integer(gpio, NULL, index);
+
+	/* Pin in the GPIO resource, typically zero */
+	acpi_dp_add_integer(gpio, NULL, pin);
+
+	/* Set if pin is active low */
+	acpi_dp_add_integer(gpio, NULL, active_low);
+
+	acpi_dp_add_array(dp, gpio);
+
+	return gpio;
+}
+
+/**
+ * acpi_device_set_i2c() - Set up an ACPI I2C struct from a device
+ *
+ * @dev: I2C device to convert
+ * @i2c: Place to put the new structure
+ * @scope: Scope of the I2C device (this is the controller path)
+ * @return 0 (always)
+ */
+static int acpi_device_set_i2c(const struct udevice *dev, struct acpi_i2c *i2c,
+			       const char *scope)
+{
+	struct dm_i2c_chip *chip = dev_get_parent_platdata(dev);
+	struct udevice *bus = dev_get_parent(dev);
+
+	memset(i2c, '\0', sizeof(i2c));
+	i2c->address = chip->chip_addr;
+	i2c->mode_10bit = 0;
+
+	/*
+	 * i2c_bus->speed_hz is set if this device is probed, but if not we
+	 * must use the device tree
+	 */
+	i2c->speed = dev_read_u32_default(bus, "clock-frequency", 100000);
+	i2c->resource = scope;
+
+	return 0;
+}
+
+int acpi_device_write_i2c_dev(struct acpi_ctx *ctx, const struct udevice *dev)
+{
+	char scope[ACPI_PATH_MAX];
+	struct acpi_i2c i2c;
+	int ret;
+
+	ret = acpi_device_scope(dev, scope, sizeof(scope));
+	if (ret)
+		return log_msg_ret("scope", ret);
+	ret = acpi_device_set_i2c(dev, &i2c, scope);
+	if (ret)
+		return log_msg_ret("set", ret);
+	acpi_device_write_i2c(ctx, &i2c);
+
+	return 0;
+}
+
+static void i2c_hid_func0_cb(struct acpi_ctx *ctx, void *arg)
+{
+	/* ToInteger (Arg1, Local2) */
+	acpigen_write_to_integer(ctx, ARG1_OP, LOCAL2_OP);
+	/* If (LEqual (Local2, 0x0)) */
+	acpigen_write_if_lequal_op_int(ctx, LOCAL2_OP, 0x0);
+	/*   Return (Buffer (One) { 0x1f }) */
+	acpigen_write_return_singleton_buffer(ctx, 0x1f);
+	acpigen_pop_len(ctx);	/* Pop : If */
+	/* Else */
+	acpigen_write_else(ctx);
+	/*   If (LEqual (Local2, 0x1)) */
+	acpigen_write_if_lequal_op_int(ctx, LOCAL2_OP, 0x1);
+	/*     Return (Buffer (One) { 0x3f }) */
+	acpigen_write_return_singleton_buffer(ctx, 0x3f);
+	acpigen_pop_len(ctx);	/* Pop : If */
+	/*   Else */
+	acpigen_write_else(ctx);
+	/*     Return (Buffer (One) { 0x0 }) */
+	acpigen_write_return_singleton_buffer(ctx, 0x0);
+	acpigen_pop_len(ctx);	/* Pop : Else */
+	acpigen_pop_len(ctx);	/* Pop : Else */
+}
+
+static void i2c_hid_func1_cb(struct acpi_ctx *ctx, void *arg)
+{
+	struct dsm_i2c_hid_config *config = arg;
+
+	acpigen_write_return_byte(ctx, config->hid_desc_reg_offset);
+}
+
+static hid_callback_func i2c_hid_callbacks[2] = {
+	i2c_hid_func0_cb,
+	i2c_hid_func1_cb,
+};
+
+void acpi_device_write_dsm_i2c_hid(struct acpi_ctx *ctx,
+				   struct dsm_i2c_hid_config *config)
+{
+	acpigen_write_dsm(ctx, ACPI_DSM_I2C_HID_UUID, i2c_hid_callbacks,
+			  ARRAY_SIZE(i2c_hid_callbacks), config);
+}
+
+static const char *acpi_name_from_id(enum uclass_id id)
+{
+	switch (id) {
+	case UCLASS_USB_HUB:
+		/* Root Hub */
+		return "RHUB";
+	/* DSDT: acpi/northbridge.asl */
+	case UCLASS_NORTHBRIDGE:
+		return "MCHC";
+	/* DSDT: acpi/lpc.asl */
+	case UCLASS_LPC:
+		return "LPCB";
+	/* DSDT: acpi/xhci.asl */
+	case UCLASS_USB:
+		return "XHCI";
+	case UCLASS_PWM:
+		return "PWM";
+	default:
+		return NULL;
+	}
+}
+
+static int acpi_check_seq(const struct udevice *dev)
+{
+	if (dev->req_seq == -1) {
+		log_warning("Device '%s' has no seq\n", dev->name);
+		return log_msg_ret("no seq", -ENXIO);
+	}
+
+	return dev->req_seq;
+}
+
+/* If you change this function, add test cases to dm_test_acpi_get_name() */
+int acpi_device_get_name(const struct udevice *dev, char *out_name)
+{
+	enum uclass_id parent_id = UCLASS_INVALID;
+	enum uclass_id id;
+	const char *name = NULL;
+
+	id = device_get_uclass_id(dev);
+	if (dev_get_parent(dev))
+		parent_id = device_get_uclass_id(dev_get_parent(dev));
+
+	if (id == UCLASS_SOUND)
+		name = "HDAS";
+	else if (id == UCLASS_PCI)
+		name = "PCI0";
+	else if (device_is_on_pci_bus(dev))
+		name = acpi_name_from_id(id);
+	if (!name) {
+		switch (parent_id) {
+		case UCLASS_USB: {
+			struct usb_device *udev = dev_get_parent_priv(dev);
+
+			sprintf(out_name, udev->speed >= USB_SPEED_SUPER ?
+				"HS%02d" : "FS%02d",
+				udev->portnr);
+			name = out_name;
+			break;
+		}
+		default:
+			break;
+		}
+	}
+	if (!name) {
+		int num;
+
+		switch (id) {
+		/* DSDT: acpi/lpss.asl */
+		case UCLASS_SERIAL:
+			num = acpi_check_seq(dev);
+			if (num < 0)
+				return num;
+			sprintf(out_name, "URT%d", num);
+			name = out_name;
+			break;
+		case UCLASS_I2C:
+			num = acpi_check_seq(dev);
+			if (num < 0)
+				return num;
+			sprintf(out_name, "I2C%d", num);
+			name = out_name;
+			break;
+		case UCLASS_SPI:
+			num = acpi_check_seq(dev);
+			if (num < 0)
+				return num;
+			sprintf(out_name, "SPI%d", num);
+			name = out_name;
+			break;
+		default:
+			break;
+		}
+	}
+	if (!name) {
+		log_warning("No name for device '%s'\n", dev->name);
+		return -ENOENT;
+	}
+	if (name != out_name)
+		memcpy(out_name, name, ACPI_NAME_MAX);
+
+	return 0;
+}
+
+int acpi_dp_ofnode_copy_int(ofnode node, struct acpi_dp *dp, const char *prop)
+{
+	int ret;
+	u32 val = 0;
+
+	ret = ofnode_read_u32(node, prop, &val);
+	acpi_dp_add_integer(dp, prop, val);
+
+	return ret;
+}
+
+int acpi_dp_ofnode_copy_str(ofnode node, struct acpi_dp *dp, const char *prop)
+{
+	const char *val;
+
+	val = ofnode_read_string(node, prop);
+	if (!val)
+		return -ENOENT;
+	acpi_dp_add_string(dp, prop, val);
+
+	return 0;
+}
+
+int acpi_dp_dev_copy_int(const struct udevice *dev, struct acpi_dp *dp,
+			 const char *prop)
+{
+	int ret;
+	u32 val = 0;
+
+	ret = dev_read_u32(dev, prop, &val);
+	acpi_dp_add_integer(dp, prop, val);
+
+	return ret;
+}
+
+int acpi_dp_dev_copy_str(const struct udevice *dev, struct acpi_dp *dp,
+			 const char *prop)
+{
+	const char *val;
+
+	val = dev_read_string(dev, prop);
+	if (!val)
+		return -ENOENT;
+	acpi_dp_add_string(dp, prop, val);
+
+	return 0;
+}