1// SPDX-License-Identifier: GPL-2.0-or-later
2/*
3 *  Copyright (c) 2000-2002 Vojtech Pavlik <vojtech@ucw.cz>
4 *  Copyright (c) 2001-2002, 2007 Johann Deneux <johann.deneux@gmail.com>
5 *
6 *  USB/RS232 I-Force joysticks and wheels.
7 */
8
9#include <asm/unaligned.h>
10#include "iforce.h"
11
12static struct {
13	__s32 x;
14	__s32 y;
15} iforce_hat_to_axis[16] = {{ 0,-1}, { 1,-1}, { 1, 0}, { 1, 1}, { 0, 1}, {-1, 1}, {-1, 0}, {-1,-1}};
16
17
18void iforce_dump_packet(struct iforce *iforce, char *msg, u16 cmd, unsigned char *data)
19{
20	dev_dbg(iforce->dev->dev.parent, "%s %s cmd = %04x, data = %*ph\n",
21		__func__, msg, cmd, LO(cmd), data);
22}
23
24/*
25 * Send a packet of bytes to the device
26 */
27int iforce_send_packet(struct iforce *iforce, u16 cmd, unsigned char* data)
28{
29	/* Copy data to buffer */
30	int n = LO(cmd);
31	int c;
32	int empty;
33	int head, tail;
34	unsigned long flags;
35
36/*
37 * Update head and tail of xmit buffer
38 */
39	spin_lock_irqsave(&iforce->xmit_lock, flags);
40
41	head = iforce->xmit.head;
42	tail = iforce->xmit.tail;
43
44
45	if (CIRC_SPACE(head, tail, XMIT_SIZE) < n+2) {
46		dev_warn(&iforce->dev->dev,
47			 "not enough space in xmit buffer to send new packet\n");
48		spin_unlock_irqrestore(&iforce->xmit_lock, flags);
49		return -1;
50	}
51
52	empty = head == tail;
53	XMIT_INC(iforce->xmit.head, n+2);
54
55/*
56 * Store packet in xmit buffer
57 */
58	iforce->xmit.buf[head] = HI(cmd);
59	XMIT_INC(head, 1);
60	iforce->xmit.buf[head] = LO(cmd);
61	XMIT_INC(head, 1);
62
63	c = CIRC_SPACE_TO_END(head, tail, XMIT_SIZE);
64	if (n < c) c=n;
65
66	memcpy(&iforce->xmit.buf[head],
67	       data,
68	       c);
69	if (n != c) {
70		memcpy(&iforce->xmit.buf[0],
71		       data + c,
72		       n - c);
73	}
74	XMIT_INC(head, n);
75
76	spin_unlock_irqrestore(&iforce->xmit_lock, flags);
77/*
78 * If necessary, start the transmission
79 */
80	if (empty)
81		iforce->xport_ops->xmit(iforce);
82
83	return 0;
84}
85EXPORT_SYMBOL(iforce_send_packet);
86
87/* Start or stop an effect */
88int iforce_control_playback(struct iforce* iforce, u16 id, unsigned int value)
89{
90	unsigned char data[3];
91
92	data[0] = LO(id);
93	data[1] = (value > 0) ? ((value > 1) ? 0x41 : 0x01) : 0;
94	data[2] = LO(value);
95	return iforce_send_packet(iforce, FF_CMD_PLAY, data);
96}
97
98/* Mark an effect that was being updated as ready. That means it can be updated
99 * again */
100static int mark_core_as_ready(struct iforce *iforce, unsigned short addr)
101{
102	int i;
103
104	if (!iforce->dev->ff)
105		return 0;
106
107	for (i = 0; i < iforce->dev->ff->max_effects; ++i) {
108		if (test_bit(FF_CORE_IS_USED, iforce->core_effects[i].flags) &&
109		    (iforce->core_effects[i].mod1_chunk.start == addr ||
110		     iforce->core_effects[i].mod2_chunk.start == addr)) {
111			clear_bit(FF_CORE_UPDATE, iforce->core_effects[i].flags);
112			return 0;
113		}
114	}
115	dev_warn(&iforce->dev->dev, "unused effect %04x updated !!!\n", addr);
116	return -1;
117}
118
119static void iforce_report_hats_buttons(struct iforce *iforce, u8 *data)
120{
121	struct input_dev *dev = iforce->dev;
122	int i;
123
124	input_report_abs(dev, ABS_HAT0X, iforce_hat_to_axis[data[6] >> 4].x);
125	input_report_abs(dev, ABS_HAT0Y, iforce_hat_to_axis[data[6] >> 4].y);
126
127	for (i = 0; iforce->type->btn[i] >= 0; i++)
128		input_report_key(dev, iforce->type->btn[i],
129				 data[(i >> 3) + 5] & (1 << (i & 7)));
130
131	/* If there are untouched bits left, interpret them as the second hat */
132	if (i <= 8) {
133		u8 btns = data[6];
134
135		if (test_bit(ABS_HAT1X, dev->absbit)) {
136			if (btns & BIT(3))
137				input_report_abs(dev, ABS_HAT1X, -1);
138			else if (btns & BIT(1))
139				input_report_abs(dev, ABS_HAT1X, 1);
140			else
141				input_report_abs(dev, ABS_HAT1X, 0);
142		}
143
144		if (test_bit(ABS_HAT1Y, dev->absbit)) {
145			if (btns & BIT(0))
146				input_report_abs(dev, ABS_HAT1Y, -1);
147			else if (btns & BIT(2))
148				input_report_abs(dev, ABS_HAT1Y, 1);
149			else
150				input_report_abs(dev, ABS_HAT1Y, 0);
151		}
152	}
153}
154
155void iforce_process_packet(struct iforce *iforce,
156			   u8 packet_id, u8 *data, size_t len)
157{
158	struct input_dev *dev = iforce->dev;
159	int i, j;
160
161	switch (packet_id) {
162
163	case 0x01:	/* joystick position data */
164		input_report_abs(dev, ABS_X,
165				 (__s16) get_unaligned_le16(data));
166		input_report_abs(dev, ABS_Y,
167				 (__s16) get_unaligned_le16(data + 2));
168		input_report_abs(dev, ABS_THROTTLE, 255 - data[4]);
169
170		if (len >= 8 && test_bit(ABS_RUDDER ,dev->absbit))
171			input_report_abs(dev, ABS_RUDDER, (__s8)data[7]);
172
173		iforce_report_hats_buttons(iforce, data);
174
175		input_sync(dev);
176		break;
177
178	case 0x03:	/* wheel position data */
179		input_report_abs(dev, ABS_WHEEL,
180				 (__s16) get_unaligned_le16(data));
181		input_report_abs(dev, ABS_GAS,   255 - data[2]);
182		input_report_abs(dev, ABS_BRAKE, 255 - data[3]);
183
184		iforce_report_hats_buttons(iforce, data);
185
186		input_sync(dev);
187		break;
188
189	case 0x02:	/* status report */
190		input_report_key(dev, BTN_DEAD, data[0] & 0x02);
191		input_sync(dev);
192
193		/* Check if an effect was just started or stopped */
194		i = data[1] & 0x7f;
195		if (data[1] & 0x80) {
196			if (!test_and_set_bit(FF_CORE_IS_PLAYED, iforce->core_effects[i].flags)) {
197				/* Report play event */
198				input_report_ff_status(dev, i, FF_STATUS_PLAYING);
199			}
200		} else if (test_and_clear_bit(FF_CORE_IS_PLAYED, iforce->core_effects[i].flags)) {
201			/* Report stop event */
202			input_report_ff_status(dev, i, FF_STATUS_STOPPED);
203		}
204
205		for (j = 3; j < len; j += 2)
206			mark_core_as_ready(iforce, get_unaligned_le16(data + j));
207
208		break;
209	}
210}
211EXPORT_SYMBOL(iforce_process_packet);
212