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/* SPDX-License-Identifier: GPL-2.0+ */
/*
* (C) Copyright 2017
* Mario Six, Guntermann & Drunck GmbH, mario.six@gdsys.cc
*/
/*
* This uclass encapsulates hardware methods to gather information about a
* board or a specific device such as hard-wired GPIOs on GPIO expanders,
* read-only data in flash ICs, or similar.
*
* The interface offers functions to read the usual standard data types (bool,
* int, string) from the device, each of which is identified by a static
* numeric ID (which will usually be defined as a enum in a header file).
*
* If for example the board had a read-only serial number flash IC, we could
* call
*
* ret = board_detect(dev);
* if (ret) {
* debug("board device not found.");
* return ret;
* }
*
* ret = board_get_int(dev, ID_SERIAL_NUMBER, &serial);
* if (ret) {
* debug("Error when reading serial number from device.");
* return ret;
* }
*
* to read the serial number.
*/
struct board_ops {
/**
* detect() - Run the hardware info detection procedure for this
* device.
* @dev: The device containing the information
*
* This operation might take a long time (e.g. read from EEPROM,
* check the presence of a device on a bus etc.), hence this is not
* done in the probe() method, but later during operation in this
* dedicated method.
*
* Return: 0 if OK, -ve on error.
*/
int (*detect)(struct udevice *dev);
/**
* get_bool() - Read a specific bool data value that describes the
* hardware setup.
* @dev: The board instance to gather the data.
* @id: A unique identifier for the bool value to be read.
* @val: Pointer to a buffer that receives the value read.
*
* Return: 0 if OK, -ve on error.
*/
int (*get_bool)(struct udevice *dev, int id, bool *val);
/**
* get_int() - Read a specific int data value that describes the
* hardware setup.
* @dev: The board instance to gather the data.
* @id: A unique identifier for the int value to be read.
* @val: Pointer to a buffer that receives the value read.
*
* Return: 0 if OK, -ve on error.
*/
int (*get_int)(struct udevice *dev, int id, int *val);
/**
* get_str() - Read a specific string data value that describes the
* hardware setup.
* @dev: The board instance to gather the data.
* @id: A unique identifier for the string value to be read.
* @size: The size of the buffer to receive the string data.
* @val: Pointer to a buffer that receives the value read.
*
* Return: 0 if OK, -ve on error.
*/
int (*get_str)(struct udevice *dev, int id, size_t size, char *val);
};
#define board_get_ops(dev) ((struct board_ops *)(dev)->driver->ops)
/**
* board_detect() - Run the hardware info detection procedure for this device.
*
* @dev: The device containing the information
*
* Return: 0 if OK, -ve on error.
*/
int board_detect(struct udevice *dev);
/**
* board_get_bool() - Read a specific bool data value that describes the
* hardware setup.
* @dev: The board instance to gather the data.
* @id: A unique identifier for the bool value to be read.
* @val: Pointer to a buffer that receives the value read.
*
* Return: 0 if OK, -ve on error.
*/
int board_get_bool(struct udevice *dev, int id, bool *val);
/**
* board_get_int() - Read a specific int data value that describes the
* hardware setup.
* @dev: The board instance to gather the data.
* @id: A unique identifier for the int value to be read.
* @val: Pointer to a buffer that receives the value read.
*
* Return: 0 if OK, -ve on error.
*/
int board_get_int(struct udevice *dev, int id, int *val);
/**
* board_get_str() - Read a specific string data value that describes the
* hardware setup.
* @dev: The board instance to gather the data.
* @id: A unique identifier for the string value to be read.
* @size: The size of the buffer to receive the string data.
* @val: Pointer to a buffer that receives the value read.
*
* Return: 0 if OK, -ve on error.
*/
int board_get_str(struct udevice *dev, int id, size_t size, char *val);
/**
* board_get() - Return the board device for the board in question.
* @devp: Pointer to structure to receive the board device.
*
* Since there can only be at most one board instance, the API can supply a
* function that returns the unique device. This is especially useful for use
* in board files.
*
* Return: 0 if OK, -ve on error.
*/
int board_get(struct udevice **devp);