/* This program is free software: you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation, either version 3 of the License, or
 * (at your option) any later version.
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program.  If not, see <http://www.gnu.org/licenses/>.
 *
 */
/** USB cable definitions and utilities
 *  @file
 *  @author King Kévin <kingkevin@cuvoodoo.info>
 *  @date 2019
 */

/** the USB pin type */
enum usb_pin_type_t {
	USB_PIN_TYPE_UNDEFINED, /*< the default type, undefined */
	USB_PIN_TYPE_GROUND, /*< ground (including ground drain) */
	USB_PIN_TYPE_POWER, /*< power (VBUS) */
	USB_PIN_TYPE_SHIELD, /*< shield */
	USB_PIN_TYPE_DIFFERENTIAL, /*< differential data pairs (D+/-, SSTX+/-, SSRX+/-) */
	USB_PIN_TYPE_IDENTIFICATION, /*< pin to identify type (often connected to power or ground through resistor) */
	USB_PIN_TYPE_OTHER, /*< any other type */
};

/** the type of connection between two pins
 *  @note to be used as bit mask
 *  @note ordered from least most most reliable/accurate
 */
enum usb_pin_connection_t {
	USB_PIN_CONNECTION_DRIVE_FLOAT = (1 << 0), /*< the output side is driven using pull/push, the input is floating */
	USB_PIN_CONNECTION_PULL_FLOAT = (1 << 1), /*< the output side is driven using pull up/down, the input is floating */
	USB_PIN_CONNECTION_DRIVE_PULL = (1 << 2), /*< the output side is driven using pull/push, the input is pulled up/down */
};

/** USB pin definition */
struct usb_pin_t {
	const char* name; /*< pin name */
	uint32_t port; /*< on which MCU port is this pin connected */
	uint16_t pin; /*< on which MCU pin is this pin connected */
	enum usb_pin_type_t type; /*< pin type */
};

/** USB connector definition */
struct usb_connector_t {
	const char* name; /*< connector name (A, B, mini-B, micro-B, C, ...) */
	bool host; /*< if on host or device side */
	uint8_t pins_nb; /*< number of pins */
	const struct usb_pin_t* pins; /*< all connector pins */
};

/** USB cable definition */
struct usb_cable_t {
	const char* name; /*< cable name */
	uint8_t connectors_nb; /*< number of connectors */
	const struct usb_connector_t** connectors; /*< list of connectors this cables uses */
	uint8_t pin_pairs_nb; /* number of connected pin pairs */
	const struct usb_pin_t* (*pin_pairs)[2]; /*< list of connected pin pairs (order does not matter) */
};

/** USB connectors definitions */
extern const struct usb_connector_t* usb_connectors[8];
/** USB cables definitions */
extern const struct usb_cable_t usb_cables[35];

/** set every pin of connector to input floating
 *  @param[in] connector connector on which to set the pins floating
 */
void usb_cables_pins_float(const struct usb_connector_t* connector);
/** set every pin to the connectors to input floating
 *  @param[in] connectors list on connectors on which to set the pins floating
 *  @param[in] connectors_nb numbers of connectors
 */
void usb_cables_connectors_float(const struct usb_connector_t** connectors, uint8_t connectors_nb);
/** test if two pins are connected
 *  @param[in] pin1 first pin
 *  @param[in] pin2 second pin
 *  @return first nibble corresponds to the connection types (usb_pin_connection_t) from pin1 to pin2, second nibble from pin2 to pin1
 *  @note setting both levels (high, low) in both directions (pin1 to pin2 and pin2 to pin1) are tested, except for ground pins
 */
uint8_t usb_cables_check_pins(const struct usb_pin_t* pin1, const struct usb_pin_t* pin2);
/** check connector for connections between pins of this connector
 *  @param[in] connector connector to check
 *  @param[out] connected which of the pins are connected (NULL to just print the pins)
 */
void usb_cables_check_intra(const struct usb_connector_t* connector, bool* connected);
/** check connectors for connections between pins of the connectors
 *  @param[in] connectors connectors to check
 *  @param[in] connectors_nb numbers of connectors
 *  @param[out] connected which of the connectors are connected (NULL to just print the connections)
 *  @note connection between pin of the same connector are not checked
 *  @note when connected is NULL all pin connections will be tested, else some might be skipped to speed scan
 */
void usb_cables_check_inter(const struct usb_connector_t** connectors, uint8_t connectors_nb, bool* connected);
/** check connectors for connections between ground pins of the connectors
 *  @param[in] connectors connectors to check
 *  @param[in] connectors_nb numbers of connectors
 *  @param[out] connected which of the connectors are connected (NULL to just print the connections)
 *  @note connection between pin on the same connector are not checked
 *  @note this is faster than usb_cables_check_inter but only checks the ground pins
 *  @note it assumes all grounds are connected (e.g. only one cable is connected)
 */
void usb_cables_check_ground(const struct usb_connector_t** connectors, uint8_t connectors_nb, bool* connected);
/** check if there is a load on the connector
 *  @param[in] connector connector to check
 *  @return if there is a load on the connector
 */
bool usb_cables_check_load(const struct usb_connector_t* connector);
/** check USB cable connections
 *  @param[in] usb_cable USB cable to check
 *  @param[out] defined number of pin pairs that are connected according to definition
 *  @param[out] undefined number of pin pairs that are connected but not according to definition
 *  @param[out] disconnected number of pin pairs that are not connected but should according to definition
 *  @return if the connections of the cable correspond to the definition
 *  @note each pair is checked in both directions
 */
bool usb_cables_check_cable(const struct usb_cable_t* usb_cable, uint8_t* defined, uint8_t* undefined, uint8_t* disconnected);