/*
   * Chromium OS cros_ec driver
   *
   * Copyright (c) 2012 The Chromium OS Authors.
   *
   * SPDX-License-Identifier:	GPL-2.0+
   */
  
  #ifndef _CROS_EC_H
  #define _CROS_EC_H
  
  #include <linux/compiler.h>
  #include <ec_commands.h>
  #include <fdtdec.h>
  #include <cros_ec_message.h>
  #include <asm/gpio.h>
  
  #ifndef CONFIG_DM_CROS_EC
  /* Which interface is the device on? */
  enum cros_ec_interface_t {
  	CROS_EC_IF_NONE,
  	CROS_EC_IF_SPI,
  	CROS_EC_IF_I2C,
  	CROS_EC_IF_LPC,	/* Intel Low Pin Count interface */
  	CROS_EC_IF_SANDBOX,
  };
  #endif
  
  /* Our configuration information */
  struct cros_ec_dev {
  #ifdef CONFIG_DM_CROS_EC
  	struct udevice *dev;		/* Transport device */
  #else
  	enum cros_ec_interface_t interface;
  	struct spi_slave *spi;		/* Our SPI slave, if using SPI */
  	int node;                       /* Our node */
  	int parent_node;		/* Our parent node (interface) */
  	unsigned int cs;		/* Our chip select */
  	unsigned int addr;		/* Device address (for I2C) */
  	unsigned int bus_num;		/* Bus number (for I2C) */
  	unsigned int max_frequency;	/* Maximum interface frequency */
  #endif
  	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 cros_ec_dev *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 cros_ec_dev *dev, struct mbkp_keyscan *scan);
  
  /**
   * 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 cros_ec_dev *dev,
  		enum ec_current_image *image);
  
  /**
   * Read the hash of the CROS-EC device firmware.
   *
   * @param dev		CROS-EC device
   * @param hash		Destination for hash information
   * @return 0 if ok, <0 on error
   */
  int cros_ec_read_hash(struct cros_ec_dev *dev,
  		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 cros_ec_dev *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 cros_ec_dev *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 cros_ec_dev **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 cros_ec_dev *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 cros_ec_dev *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 cros_ec_dev *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 cros_ec_dev *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 cros_ec_dev *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 cros_ec_dev *dev,
  			 const uint8_t  *image, int image_size);
  
  /**
   * Return a pointer to the board's CROS-EC device
   *
   * This should be implemented by board files.
   *
   * @return pointer to CROS-EC device, or NULL if none is available
   */
  struct cros_ec_dev *board_get_cros_ec_dev(void);
  
  #ifdef CONFIG_DM_CROS_EC
  
  struct dm_cros_ec_ops {
  	int (*check_version)(struct udevice *dev);
  	int (*command)(struct udevice *dev, uint8_t cmd, int cmd_version,
  		       const uint8_t *dout, int dout_len,
  		       uint8_t **dinp, int din_len);
  	int (*packet)(struct udevice *dev, int out_bytes, int in_bytes);
  };
  
  #define dm_cros_ec_get_ops(dev) \
  		((struct dm_cros_ec_ops *)(dev)->driver->ops)
  
  int cros_ec_register(struct udevice *dev);
  
  #else /* !CONFIG_DM_CROS_EC */
  
  /* Internal interfaces */
  int cros_ec_i2c_init(struct cros_ec_dev *dev, const void *blob);
  int cros_ec_spi_init(struct cros_ec_dev *dev, const void *blob);
  int cros_ec_lpc_init(struct cros_ec_dev *dev, const void *blob);
  int cros_ec_sandbox_init(struct cros_ec_dev *dev, const void *blob);
  
  /**
   * Read information from the fdt for the i2c cros_ec interface
   *
   * @param dev		CROS-EC device
   * @param blob		Device tree blob
   * @return 0 if ok, -1 if we failed to read all required information
   */
  int cros_ec_i2c_decode_fdt(struct cros_ec_dev *dev, const void *blob);
  
  /**
   * Read information from the fdt for the spi cros_ec interface
   *
   * @param dev		CROS-EC device
   * @param blob		Device tree blob
   * @return 0 if ok, -1 if we failed to read all required information
   */
  int cros_ec_spi_decode_fdt(struct cros_ec_dev *dev, const void *blob);
  
  /**
   * Read information from the fdt for the sandbox cros_ec interface
   *
   * @param dev		CROS-EC device
   * @param blob		Device tree blob
   * @return 0 if ok, -1 if we failed to read all required information
   */
  int cros_ec_sandbox_decode_fdt(struct cros_ec_dev *dev, const void *blob);
  
  /**
   * Check whether the LPC interface supports new-style commands.
   *
   * LPC has its own way of doing this, which involves checking LPC values
   * visible to the host. Do this, and update dev->protocol_version accordingly.
   *
   * @param dev		CROS-EC device to check
   */
  int cros_ec_lpc_check_version(struct cros_ec_dev *dev);
  
  /**
   * Send a command to an I2C CROS-EC device and return the reply.
   *
   * This rather complicated function deals with sending both old-style and
   * new-style commands. The old ones have just a command byte and arguments.
   * The new ones have version, command, arg-len, [args], chksum so are 3 bytes
   * longer.
   *
   * The device's internal input/output buffers are used.
   *
   * @param dev		CROS-EC device
   * @param cmd		Command to send (EC_CMD_...)
   * @param cmd_version	Version of command to send (EC_VER_...)
   * @param dout          Output data (may be NULL If dout_len=0)
   * @param dout_len      Size of output data in bytes
   * @param dinp          Returns pointer to response data
   * @param din_len       Maximum size of response in bytes
   * @return number of bytes in response, or -1 on error
   */
  int cros_ec_i2c_command(struct cros_ec_dev *dev, uint8_t cmd, int cmd_version,
  		     const uint8_t *dout, int dout_len,
  		     uint8_t **dinp, int din_len);
  
  /**
   * Send a command to a LPC CROS-EC device and return the reply.
   *
   * The device's internal input/output buffers are used.
   *
   * @param dev		CROS-EC device
   * @param cmd		Command to send (EC_CMD_...)
   * @param cmd_version	Version of command to send (EC_VER_...)
   * @param dout          Output data (may be NULL If dout_len=0)
   * @param dout_len      Size of output data in bytes
   * @param dinp          Returns pointer to response data
   * @param din_len       Maximum size of response in bytes
   * @return number of bytes in response, or -1 on error
   */
  int cros_ec_lpc_command(struct cros_ec_dev *dev, uint8_t cmd, int cmd_version,
  		     const uint8_t *dout, int dout_len,
  		     uint8_t **dinp, int din_len);
  
  int cros_ec_spi_command(struct cros_ec_dev *dev, uint8_t cmd, int cmd_version,
  		     const uint8_t *dout, int dout_len,
  		     uint8_t **dinp, int din_len);
  
  /**
   * Send a packet to a CROS-EC device and return the response packet.
   *
   * Expects the request packet to be stored in dev->dout.  Stores the response
   * packet in dev->din.
   *
   * @param dev		CROS-EC device
   * @param out_bytes	Size of request packet to output
   * @param in_bytes	Maximum size of response packet to receive
   * @return number of bytes in response packet, or <0 on error
   */
  int cros_ec_spi_packet(struct cros_ec_dev *dev, int out_bytes, int in_bytes);
  int cros_ec_sandbox_packet(struct cros_ec_dev *dev, int out_bytes,
  			   int in_bytes);
  #endif
  
  /**
   * 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);
  
  /**
   * Decode a flash region parameter
   *
   * @param argc	Number of params remaining
   * @param argv	List of remaining parameters
   * @return flash region (EC_FLASH_REGION_...) or -1 on error
   */
  int cros_ec_decode_region(int argc, char * const argv[]);
  
  int cros_ec_flash_erase(struct cros_ec_dev *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 cros_ec_dev *dev, uint8_t *data, uint32_t offset,
  		    uint32_t size);
  
  /**
   * 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 cros_ec_dev *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 cros_ec_dev *dev, enum ec_flash_region region,
  		      uint32_t *offset, uint32_t *size);
  
  /**
   * Read/write VbNvContext 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_vbnvcontext(struct cros_ec_dev *dev, uint8_t *block);
  int cros_ec_write_vbnvcontext(struct cros_ec_dev *dev, const uint8_t *block);
  
  /**
   * 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 cros_ec_dev *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 cros_ec_dev *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 cros_ec_dev *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 cros_ec_dev *dev, uint8_t index, uint8_t *state);
  
  /**
   * Initialize the Chrome OS EC at board initialization time.
   *
   * @return 0 if ok, -ve on error
   */
  int cros_ec_board_init(void);
  
  /**
   * 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 blob		FDT blob to use
   * @param node		Node offset to read from
   * @param config	Structure to use to return information
   */
  int cros_ec_decode_ec_flash(const void *blob, int node,
  			    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 cros_ec_dev *dev);
  
  /*
   * Tunnel an I2C transfer to the EC
   *
   * @param dev		CROS-EC device
   * @param chip		Chip address (7-bit I2C address)
   * @param addr		Register address to read/write
   * @param alen		Length of register address in bytes
   * @param buffer	Buffer containing data to read/write
   * @param len		Length of buffer
   * @param is_read	1 if this is a read, 0 if this is a write
   */
  int cros_ec_i2c_xfer(struct cros_ec_dev *dev, uchar chip, uint addr,
  		     int alen, uchar *buffer, int len, int is_read);
  
  #endif