path: root/drivers/net/can/usb/gs_usb.c

// SPDX-License-Identifier: GPL-2.0-only
/* CAN driver for Geschwister Schneider USB/CAN devices
 * and bytewerk.org candleLight USB CAN interfaces.
 *
 * Copyright (C) 2013-2016 Geschwister Schneider Technologie-,
 * Entwicklungs- und Vertriebs UG (Haftungsbeschränkt).
 * Copyright (C) 2016 Hubert Denkmair
 *
 * Many thanks to all socketcan devs!
 */

#include <linux/bitfield.h>
#include <linux/ethtool.h>
#include <linux/init.h>
#include <linux/module.h>
#include <linux/netdevice.h>
#include <linux/signal.h>
#include <linux/usb.h>

#include <linux/can.h>
#include <linux/can/dev.h>
#include <linux/can/error.h>

/* Device specific constants */
#define USB_GSUSB_1_VENDOR_ID 0x1d50
#define USB_GSUSB_1_PRODUCT_ID 0x606f

#define USB_CANDLELIGHT_VENDOR_ID 0x1209
#define USB_CANDLELIGHT_PRODUCT_ID 0x2323

#define USB_CES_CANEXT_FD_VENDOR_ID 0x1cd2
#define USB_CES_CANEXT_FD_PRODUCT_ID 0x606f

#define USB_ABE_CANDEBUGGER_FD_VENDOR_ID 0x16d0
#define USB_ABE_CANDEBUGGER_FD_PRODUCT_ID 0x10b8

#define GSUSB_ENDPOINT_IN 1
#define GSUSB_ENDPOINT_OUT 2

/* Device specific constants */
enum gs_usb_breq {
	GS_USB_BREQ_HOST_FORMAT = 0,
	GS_USB_BREQ_BITTIMING,
	GS_USB_BREQ_MODE,
	GS_USB_BREQ_BERR,
	GS_USB_BREQ_BT_CONST,
	GS_USB_BREQ_DEVICE_CONFIG,
	GS_USB_BREQ_TIMESTAMP,
	GS_USB_BREQ_IDENTIFY,
	GS_USB_BREQ_GET_USER_ID,
	GS_USB_BREQ_QUIRK_CANTACT_PRO_DATA_BITTIMING = GS_USB_BREQ_GET_USER_ID,
	GS_USB_BREQ_SET_USER_ID,
	GS_USB_BREQ_DATA_BITTIMING,
	GS_USB_BREQ_BT_CONST_EXT,
};

enum gs_can_mode {
	/* reset a channel. turns it off */
	GS_CAN_MODE_RESET = 0,
	/* starts a channel */
	GS_CAN_MODE_START
};

enum gs_can_state {
	GS_CAN_STATE_ERROR_ACTIVE = 0,
	GS_CAN_STATE_ERROR_WARNING,
	GS_CAN_STATE_ERROR_PASSIVE,
	GS_CAN_STATE_BUS_OFF,
	GS_CAN_STATE_STOPPED,
	GS_CAN_STATE_SLEEPING
};

enum gs_can_identify_mode {
	GS_CAN_IDENTIFY_OFF = 0,
	GS_CAN_IDENTIFY_ON
};

/* data types passed between host and device */

/* The firmware on the original USB2CAN by Geschwister Schneider
 * Technologie Entwicklungs- und Vertriebs UG exchanges all data
 * between the host and the device in host byte order. This is done
 * with the struct gs_host_config::byte_order member, which is sent
 * first to indicate the desired byte order.
 *
 * The widely used open source firmware candleLight doesn't support
 * this feature and exchanges the data in little endian byte order.
 */
struct gs_host_config {
	__le32 byte_order;
} __packed;

struct gs_device_config {
	u8 reserved1;
	u8 reserved2;
	u8 reserved3;
	u8 icount;
	__le32 sw_version;
	__le32 hw_version;
} __packed;

#define GS_CAN_MODE_NORMAL 0
#define GS_CAN_MODE_LISTEN_ONLY BIT(0)
#define GS_CAN_MODE_LOOP_BACK BIT(1)
#define GS_CAN_MODE_TRIPLE_SAMPLE BIT(2)
#define GS_CAN_MODE_ONE_SHOT BIT(3)
#define GS_CAN_MODE_HW_TIMESTAMP BIT(4)
/* GS_CAN_FEATURE_IDENTIFY BIT(5) */
/* GS_CAN_FEATURE_USER_ID BIT(6) */
#define GS_CAN_MODE_PAD_PKTS_TO_MAX_PKT_SIZE BIT(7)
#define GS_CAN_MODE_FD BIT(8)
/* GS_CAN_FEATURE_REQ_USB_QUIRK_LPC546XX BIT(9) */
/* GS_CAN_FEATURE_BT_CONST_EXT BIT(10) */

struct gs_device_mode {
	__le32 mode;
	__le32 flags;
} __packed;

struct gs_device_state {
	__le32 state;
	__le32 rxerr;
	__le32 txerr;
} __packed;

struct gs_device_bittiming {
	__le32 prop_seg;
	__le32 phase_seg1;
	__le32 phase_seg2;
	__le32 sjw;
	__le32 brp;
} __packed;

struct gs_identify_mode {
	__le32 mode;
} __packed;

#define GS_CAN_FEATURE_LISTEN_ONLY BIT(0)
#define GS_CAN_FEATURE_LOOP_BACK BIT(1)
#define GS_CAN_FEATURE_TRIPLE_SAMPLE BIT(2)
#define GS_CAN_FEATURE_ONE_SHOT BIT(3)
#define GS_CAN_FEATURE_HW_TIMESTAMP BIT(4)
#define GS_CAN_FEATURE_IDENTIFY BIT(5)
#define GS_CAN_FEATURE_USER_ID BIT(6)
#define GS_CAN_FEATURE_PAD_PKTS_TO_MAX_PKT_SIZE BIT(7)
#define GS_CAN_FEATURE_FD BIT(8)
#define GS_CAN_FEATURE_REQ_USB_QUIRK_LPC546XX BIT(9)
#define GS_CAN_FEATURE_BT_CONST_EXT BIT(10)
#define GS_CAN_FEATURE_MASK GENMASK(10, 0)

/* internal quirks - keep in GS_CAN_FEATURE space for now */

/* CANtact Pro original firmware:
 * BREQ DATA_BITTIMING overlaps with GET_USER_ID
 */
#define GS_CAN_FEATURE_QUIRK_BREQ_CANTACT_PRO BIT(31)

struct gs_device_bt_const {
	__le32 feature;
	__le32 fclk_can;
	__le32 tseg1_min;
	__le32 tseg1_max;
	__le32 tseg2_min;
	__le32 tseg2_max;
	__le32 sjw_max;
	__le32 brp_min;
	__le32 brp_max;
	__le32 brp_inc;
} __packed;

struct gs_device_bt_const_extended {
	__le32 feature;
	__le32 fclk_can;
	__le32 tseg1_min;
	__le32 tseg1_max;
	__le32 tseg2_min;
	__le32 tseg2_max;
	__le32 sjw_max;
	__le32 brp_min;
	__le32 brp_max;
	__le32 brp_inc;

	__le32 dtseg1_min;
	__le32 dtseg1_max;
	__le32 dtseg2_min;
	__le32 dtseg2_max;
	__le32 dsjw_max;
	__le32 dbrp_min;
	__le32 dbrp_max;
	__le