path: root/include/cros_ec.h

/* SPDX-License-Identifier: GPL-2.0+ */
/*
 * Chromium OS cros_ec driver
 *
 * Copyright (c) 2012 The Chromium OS Authors.
 */

#ifndef _CROS_EC_H
#define _CROS_EC_H

#include <linux/compiler.h>
#include <ec_commands.h>
#include <cros_ec_message.h>
#include <asm/gpio.h>
#include <dm/of_extra.h>

/* Our configuration information */
struct cros_ec_dev {
	struct udevice *dev;		/* Transport device */
	struct gpio_desc ec_int;	/* GPIO used as EC interrupt line */
	int protocol_version;           /* Protocol version to use */
	int optimise_flash_write;	/* Don't write erased flash blocks */

	/*
	 * These two buffers will always be dword-aligned and include enough
	 * space for up to 7 word-alignment bytes also, so we can ensure that
	 * the body of the message is always dword-aligned (64-bit).
	 *
	 * We use this alignment to keep ARM and x86 happy. Probably word
	 * alignment would be OK, there might be a small performance advantage
	 * to using dword.
	 */
	uint8_t din[ALIGN(MSG_BYTES + sizeof(int64_t), sizeof(int64_t))]
		__aligned(sizeof(int64_t));
	uint8_t dout[ALIGN(MSG_BYTES + sizeof(int64_t), sizeof(int64_t))]
		__aligned(sizeof(int64_t));
};

/*
 * Hard-code the number of columns we happen to know we have right now.  It
 * would be more correct to call cros_ec_info() at startup and determine the
 * actual number of keyboard cols from there.
 */
#define CROS_EC_KEYSCAN_COLS 13

/* Information returned by a key scan */
struct mbkp_keyscan {
	uint8_t data[CROS_EC_KEYSCAN_COLS];
};

/* Holds information about the Chrome EC */
struct fdt_cros_ec {
	struct fmap_entry flash;	/* Address and size of EC flash */
	/*
	 * Byte value of erased flash, or -1 if not known. It is normally
	 * 0xff but some flash devices use 0 (e.g. STM32Lxxx)
	 */
	int flash_erase_value;
	struct fmap_entry region[EC_FLASH_REGION_COUNT];
};

/**
 * Read the ID of the CROS-EC device
 *
 * The ID is a string identifying the CROS-EC device.
 *
 * @param dev		CROS-EC device
 * @param id		Place to put the ID
 * @param maxlen	Maximum length of the ID field
 * Return: 0 if ok, -1 on error
 */
int cros_ec_read_id(struct udevice *dev, char *id, int maxlen);

/**
 * Read a keyboard scan from the CROS-EC device
 *
 * Send a message requesting a keyboard scan and return the result
 *
 * @param dev		CROS-EC device
 * @param scan		Place to put the scan results
 * Return: 0 if ok, -1 on error
 */
int cros_ec_scan_keyboard(struct udevice *dev, struct mbkp_keyscan *scan);

/**
 * Get the next pending MKBP event from the ChromeOS EC device.
 *
 * Send a message requesting the next event and return the result.
 *
 * @param event		Place to put the event.
 * Return: 0 if ok, <0 on error.
 */
int cros_ec_get_next_event(struct udevice *dev,
			   struct ec_response_get_next_event *event);

/**
 * Read which image is currently running on the CROS-EC device.
 *
 * @param dev		CROS-EC device
 * @param image		Destination for image identifier
 * Return: 0 if ok, <0 on error
 */
int cros_ec_read_current_image(struct udevice *dev,
			       enum ec_current_image *image);

/**
 * Read the hash of the CROS-EC device firmware.
 *
 * @param dev		CROS-EC device
 * @param hash_offset	Offset in flash to read from
 * @param hash		Destination for hash information
 * Return: 0 if ok, <0 on error
 */
int cros_ec_read_hash(struct udevice *dev, uint hash_offset,
		      struct ec_response_vboot_hash *hash);

/**
 * Send a reboot command to the CROS-EC device.
 *
 * Note that some reboot commands (such as EC_REBOOT_COLD) also reboot the AP.
 *
 * @param dev		CROS-EC device
 * @param cmd		Reboot command
 * @param flags         Flags for reboot command (EC_REBOOT_FLAG_*)
 * Return: 0 if ok, <0 on error
 */
int cros_ec_reboot(struct udevice *dev, enum ec_reboot_cmd cmd, uint8_t flags);

/**
 * Check if the CROS-EC device has an interrupt pending.
 *
 * Read the status of the external interrupt connected to the CROS-EC device.
 * If no external interrupt is configured, this always returns 1.
 *
 * @param dev		CROS-EC device
 * Return: 0 if no interrupt is pending
 */
int cros_ec_interrupt_pending(struct udevice *dev);

enum {
	CROS_EC_OK,
	CROS_EC_ERR = 1,
	CROS_EC_ERR_FDT_DECODE,
	CROS_EC_ERR_CHECK_VERSION,
	CROS_EC_ERR_READ_ID,
	CROS_EC_ERR_DEV_INIT,
};

/**
 * Initialise the Chromium OS EC driver
 *
 * @param blob		Device tree blob containing setup information
 * @param cros_ecp        Returns pointer to the cros_ec device, or NULL if none
 * Return: 0 if we got an cros_ec device and all is well (or no cros_ec is
 *	expected), -ve if we should have an cros_ec device but failed to find
 *	one, or init failed (-CROS_EC_ERR_...).
 */
int cros_ec_init(const void *blob, struct udevice**cros_ecp);

/**
 * Read information about the keyboard matrix
 *
 * @param dev		CROS-EC device
 * @param info		Place to put the info structure
 */
int cros_ec_info(struct udevice *dev, struct ec_response_mkbp_info *info);

/**
 * Read the host event flags
 *
 * @param dev		CROS-EC device
 * @param events_ptr	Destination for event flags.  Not changed on error.
 * Return: 0 if ok, <0 on error
 */
int cros_ec_get_host_events(struct udevice *dev, uint32_t *events_ptr);

/**
 * Clear the specified host event flags
 *
 * @param dev		CROS-EC device
 * @param events	Event flags to clear
 * Return: 0 if ok, <0 on error
 */
int cros_ec_clear_host_events(struct udevice *dev, uint32_t events);

/**
 * Get/set flash protection
 *
 * @param dev		CROS-EC device
 * @param set_mask	Mask of flags to set; if 0, just retrieves existing
 *                      protection state without changing it.
 * @param set_flags	New flag values; only bits in set_mask are applied;
 *                      ignored if set_mask=0.
 * @param prot          Destination for updated protection state from EC.
 * Return: 0 if ok, <0 on error
 */
int cros_ec_flash_protect(struct udevice *dev, uint32_t set_mask,
			  uint32_t set_flags,
			  struct ec_response_flash_protect *resp);

/**
 * Run internal tests on the cros_ec interface.
 *
 * @param dev		CROS-EC device
 * Return: 0 if ok, <0 if the test failed
 */
int cros_ec_test(struct udevice *dev);

/**
 * Update the EC RW copy.
 *
 * @param dev		CROS-EC device
 * @param image		the content to write
 * @param imafge_size	content length
 * Return: 0 if ok, <0 if the test failed
 */
int cros_ec_flash_update_rw(struct udevice *dev, const uint8_t  *image,
			    int image_size);

/**
 * Return a pointer to the board's CROS-EC device
 *
 * Return: pointer to CROS-EC device, or NULL if none is available
 */
struct udevice *board_get_cros_ec_dev(void);

struct dm_cros_ec_ops {
	/**
	 * check_version() - Check the protocol version being used (optional)
	 *
	 * If provided, this function should check that the EC can be supported
	 * by the driver. If not provided, HELLO messages will be sent to try
	 * to determine the protocol version.
	 *
	 * @dev: Device to check
	 * @return 0 if the protocol is valid, -ve if not supported
	 */
	int (*check_version)(struct udevice *dev);

	/**
	 * command() - Old-style command interface
	 *
	 * This sends a command and receives a response (deprecated, use
	 * packet())
	 *
	 * @dev: Device to use
	 * @cmd: Command to send (only supports 0-0xff)
	 * @cmd_version: Version of command to send (often 0)
	 * @dout: Output data (may be NULL If dout_len=0)
	 * @dout_len: Length of output data excluding 4-byte header
	 * @dinp: On input, set to point to input data, often struct
	 *	cros_ec_dev->din - typically this is left alone but may be
	 *	updated by the driver
	 * @din_len: Maximum length of response
	 * @return number of bytes in response, or -ve on error
	 */
	int (*command)(struct udevice *dev, uint8_t cmd, int cmd_version,
		       const uint8_t *dout, int dout_len,
		       uint8_t **dinp, int din_len);

	/**
	 * packet() - New-style command interface
	 *
	 * This interface is preferred over command(), since it is typically
	 * easier to implement.
	 *
	 * @dev: Device to use
	 * @out_bytes: Number of bytes to send (from struct cros_ec_dev->dout)
	 * @in_bytes: Maximum number of bytes to expect in response
	 * @return number of bytes in response, or -ve on error
	 */
	int (*packet)(struct udevice *dev, int out_bytes, int in_bytes);

	/**
	 * get_switches() - Get value of EC switches
	 *
	 * This is currently supported on the LPC EC.
	 *
	 * @dev: Device to use
	 * @return current switches value, or -ENOSYS if not supported
	 */
	int (*get_switches)(struct udevice *dev);
};

#define dm_cros_ec_get_ops(dev) \
		((struct dm_cros_ec_ops *)(dev)->driver->ops)

int cros_ec_register(struct udevice *dev);

/**
 * Dump a block of data for a command.
 *
 * @param name	Name for data (e.g. 'in', 'out')
 * @param cmd	Command number associated with data, or -1 for none
 * @param data	Data block to dump
 * @param len	Length of data block to dump
 */
void cros_ec_dump_data(const char *name, int cmd, const uint8_t *data, int len);

/**
 * Calculate a simple 8-bit checksum of a data block
 *
 * @param data	Data block to checksum
 * @param size	Size of data block in bytes
 * Return: checksum value (0 to 255)
 */
int cros_ec_calc_checksum(const uint8_t *data, int size);

int cros_ec_flash_erase(struct udevice *dev, uint32_t offset, uint32_t size);

/**
 * Read data from the flash
 *
 * Read an arbitrary amount of data from the EC flash, by repeatedly reading
 * small blocks.
 *
 * The offset starts at 0. You can obtain the region information from
 * cros_ec_flash_offset() to find out where to read for a particular region.
 *
 * @param dev		CROS-EC device
 * @param data		Pointer to data buffer to read into
 * @param offset	Offset within flash to read from
 * @param size		Number of bytes to read
 * Return: 0 if ok, -1 on error
 */
int cros_ec_flash_read(struct udevice *dev, uint8_t *data, uint32_t offset,
		       uint32_t size);

/**
 * Read back flash parameters
 *
 * This function reads back parameters of the flash as reported by the EC
 *
 * @param dev  Pointer to device
 * @param info Pointer to output flash info struct
 */
int cros_ec_read_flashinfo(struct udevice *dev,
			   struct ec_response_flash_info *info);

/**
 * Write data to the flash
 *
 * Write an arbitrary amount of data to the EC flash, by repeatedly writing
 * small blocks.
 *
 * The offset starts at 0. You can obtain the region information from
 * cros_ec_flash_offset() to find out where to write for a particular region.
 *
 * Attempting to write to the region where the EC is currently running from
 * will result in an error.
 *
 * @param dev		CROS-EC device
 * @param data		Pointer to data buffer to write
 * @param offset	Offset within flash to write to.
 * @param size		Number of bytes to write
 * Return: 0 if ok, -1 on error
 */
int cros_ec_flash_write(struct udevice *dev, const uint8_t *data,
			uint32_t offset, uint32_t size);

/**
 * Obtain position and size of a flash region
 *
 * @param dev		CROS-EC device
 * @param region	Flash region to query
 * @param offset	Returns offset of flash region in EC flash
 * @param size		Returns size of flash region
 * Return: 0 if ok, -1 on error
 */
int cros_ec_flash_offset(struct udevice *dev, enum ec_flash_region region,
			 uint32_t *offset, uint32_t *size);

/**
 * cros_ec_get_sku_id() - Read the SKU ID
 *
 * @dev: CROS-EC device
 * return SKU ID, or -ve on error
 */
int cros_ec_get_sku_id(struct udevice *dev);

/**
 * Read/write non-volatile data from/to a CROS-EC device.
 *
 * @param dev		CROS-EC device
 * @param block		Buffer of VbNvContext to be read/write
 * Return: 0 if ok, -1 on error
 */
int cros_ec_read_nvdata(struct udevice *dev, uint8_t *block, int size);
int cros_ec_write_nvdata(struct udevice *dev, const uint8_t *block, int size);

/**
 * Read the version information for the EC images
 *
 * @param dev		CROS-EC device
 * @param versionp	This is set to point to the version information
 * Return: 0 if ok, -1 on error
 */
int cros_ec_read_version(struct udevice *dev,
			 struct ec_response_get_version **versionp);

/**
 * Read the build information for the EC
 *
 * @param dev		CROS-EC device
 * @param versionp	This is set to point to the build string
 * Return: 0 if ok, -1 on error
 */
int cros_ec_read_build_info(struct udevice *dev, char **strp);

/**
 * Switch on/off a LDO / FET.
 *
 * @param dev		CROS-EC device
 * @param index		index of the LDO/FET to switch
 * @param state		new state of the LDO/FET : EC_LDO_STATE_ON|OFF
 * Return: 0 if ok, -1 on error
 */
int cros_ec_set_ldo(struct udevice *dev, uint8_t index, uint8_t state);

/**
 * Read back a LDO / FET current state.
 *
 * @param dev		CROS-EC device
 * @param index		index of the LDO/FET to switch
 * @param state		current state of the LDO/FET : EC_LDO_STATE_ON|OFF
 * Return: 0 if ok, -1 on error
 */
int cros_ec_get_ldo(struct udevice *dev, uint8_t index, uint8_t *state);

/**
 * Get access to the error reported when cros_ec_board_init() was called
 *
 * This permits delayed reporting of the EC error if it failed during
 * early init.
 *
 * Return: error (0 if there was no error, -ve if there was an error)
 */
int cros_ec_get_error(void);

/**
 * Returns information from the FDT about the Chrome EC flash
 *
 * @param dev		Device to read from
 * @param config	Structure to use to return information
 */
int cros_ec_decode_ec_flash(struct udevice *dev, struct fdt_cros_ec *config);

/**
 * Check the current keyboard state, in case recovery mode is requested.
 * This function is for sandbox only.
 *
 * @param ec		CROS-EC device
 */
void cros_ec_check_keyboard(struct udevice *dev);

struct i2c_msg;
/*
 * Tunnel an I2C transfer to the EC
 *
 * @param dev		CROS-EC device
 * @param port		The remote port on EC to use
 * @param msg		List of messages to transfer
 * @param nmsgs		Number of messages to transfer
 */
int cros_ec_i2c_tunnel(struct udevice *dev, int port, struct i2c_msg *msg,
		       int nmsgs);

/**
 * cros_ec_get_events_b() - Get event mask B
 *
 * Return: value of event mask, default value of 0 if it could not be read
 */
uint64_t cros_ec_get_events_b(struct udevice *dev);

/**
 * cros_ec_clear_events_b() - Clear even mask B
 *
 * Any pending events in the B range are cleared
 *
 * Return: 0 if OK, -ve on error
 */
int cros_ec_clear_events_b(struct udevice *dev, uint64_t mask);

/**
 * cros_ec_efs_verify() - tell the EC to verify one of its images
 *
 * @param dev		CROS-EC device
 * @param region	Flash region to query
 * Return: 0 if OK, -ve on error
 */
int cros_ec_efs_verify(struct udevice *dev, enum ec_flash_region region);

/**
 * cros_ec_battery_cutoff() - Request that the battery be cut off
 *
 * This tells the battery to stop supplying power. This is used before shipping
 * a device to ensure that the battery remains charged while the device is
 * shipped or sitting on the shelf waiting to be purchased.
 *
 * @param dev		CROS-EC device
 * @param flags		Flags to use (EC_BATTERY_CUTOFF_FLAG_...)
 * Return: 0 if OK, -ve on error
 */
int cros_ec_battery_cutoff(struct udevice *dev, uint8_t flags);

/**
 * cros_ec_set_pwm_duty() - Set duty cycle of a generic pwm
 *
 * Note that duty value needs to be passed to the EC as a 16 bit number
 * for increased precision.
 *
 * @param dev		CROS-EC device
 * @param index		Index of the pwm
 * @param duty		Desired duty cycle, in 0..EC_PWM_MAX_DUTY range.
 * Return: 0 if OK, -ve on error
 */
int cros_ec_set_pwm_duty(struct udevice *dev, uint8_t index, uint16_t duty);

/**
 * cros_ec_read_limit_power() - Check if power is limited by batter/charger
 *
 * Sometimes the battery is low and / or the device is connected to a charger
 * that cannot supply much power.
 *
 * @param dev		CROS-EC device
 * @param limit_powerp	Returns whether power is limited (0 or 1)
 * Return: 0 if OK, -ENOSYS if the EC does not support this comment, -EINVAL
 *		if the EC returned an invalid response
 */
int cros_ec_read_limit_power(struct udevice *dev, int *limit_powerp);

/**
 * cros_ec_config_powerbtn() - Configure the behaviour of the power button
 *
 * @param dev		CROS-EC device
 * @param flags		Flags to use (EC_POWER_BUTTON_...)
 * Return: 0 if OK, -ve on error
 */
int cros_ec_config_powerbtn(struct udevice *dev, uint32_t flags);

/**
 * cros_ec_get_lid_shutdown_mask() - Set the lid shutdown mask
 *
 * Determines whether a lid close event is reported
 *
 * @param dev		CROS-EC device
 * Return: shufdown mas if OK, -ve on error
 */
int cros_ec_get_lid_shutdown_mask(struct udevice *dev);

/**
 * cros_ec_set_lid_shutdown_mask() - Set the lid shutdown mask
 *
 * Set whether a lid close event is reported
 *
 * @param dev		CROS-EC device
 * @param enable	true to enable reporting, false to disable
 * Return: shufdown mas if OK, -ve on error
 */
int cros_ec_set_lid_shutdown_mask(struct udevice *dev, int enable);

/**
 * cros_ec_hello() - Send a hello message
 *
 * Sends a message with a fixed input value and checks that the expected output
 * value is received
 *
 * @dev: CROS-EC device
 * @handshakep: If non-NULL, returns received handshake value on error
 * Return: 0 if OK, -ve on error
 */
int cros_ec_hello(struct udevice *dev, uint *handshakep);

/**
 * cros_ec_get_features() - Get the set of features provided by the EC
 *
 * See enum ec_feature_code for the list of available features
 *
 * @dev: CROS-EC device
 * @featuresp: Returns a bitmask of supported features
 * Return: 0 if OK, -ve on error
 */
int cros_ec_get_features(struct udevice *dev, u64 *featuresp);

/**
 * cros_ec_check_feature() - Check if a feature is supported
 *
 * @dev: CROS-EC device
 * @feature: Feature number to check (enum ec_feature_code)
 * Return: true if supported, false if not, -ve on error
 */
int cros_ec_check_feature(struct udevice *dev, uint feature);

/**
 * cros_ec_get_switches() - Get switches value
 *
 * @dev: CROS-EC device
 * Return: switches value, or -ENOSYS if not supported, or other -ve value on
 *	other error
 */
int cros_ec_get_switches(struct udevice *dev);

/**
 * cros_ec_vstore_supported() - Check if vstore is supported
 *
 * @dev: CROS-EC device
 * Return: false if not supported, true if supported, -ve on error
 */
int cros_ec_vstore_supported(struct udevice *dev);

/**
 * cros_ec_vstore_info() - Get vstore information
 *
 * @dev: CROS-EC device
 * @lockedp: mask of locked slots
 * Return: number of vstore slots supported by the EC,, -ve on error
 */
int cros_ec_vstore_info(struct udevice *dev, u32 *lockedp);

/**
 * cros_ec_vstore_read() - Read data from EC vstore slot
 *
 * @dev: CROS-EC device
 * @slot: vstore slot to read from
 * @data: buffer to store read data, must be EC_VSTORE_SLOT_SIZE bytes
 * Return: 0 if OK, -ve on error
 */
int cros_ec_vstore_read(struct udevice *dev, int slot, uint8_t *data);

/**
 * cros_ec_vstore_write() - Save data into EC vstore slot
 *
 * The maximum size of data is EC_VSTORE_SLOT_SIZE.  It is the caller's
 * responsibility to check the number of implemented slots by querying the
 * vstore info.
 *
 * @dev: CROS-EC device
 * @slot: vstore slot to write into
 * @data: data to write
 * @size: size of data in bytes
 * Return: 0 if OK, -ve on error
 */
int cros_ec_vstore_write(struct udevice *dev, int slot, const uint8_t *data,
			 size_t size);

/**
 * cros_ec_read_batt_charge() - Read the battery-charge state
 *
 * @dev: CROS-EC device
 * @chargep: Return battery-charge state as a percentage
 * Return: 0 if OK, -ve on error
 */
int cros_ec_read_batt_charge(struct udevice *dev, uint *chargep);

#endif