summaryrefslogtreecommitdiffstats
path: root/usb/endpt0.c
blob: 57c994ec57f406eada4bf9af842fb609ce428aa4 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
/*
 * usb/endpt0.c -- USB endpoint 0 (control) handling
 *
 * Copyright (C) 2016-2017 Tomasz Kramkowski <tk@the-tk.com>
 *
 * 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/>.
 */
#include <arrlen.h>
#include <le.h>
#include <reg/usbotg.h>
#include <stdbool.h>
#include <stddef.h>
#include <stdint.h>

#include <reg/gpio.h>

#include "bdt.h"
#include "endpt0.h"
#include "endpt1.h"

#include "descriptors.h"

#define MAX_PACKET 64
static unsigned char buf[2][MAX_PACKET];
static bool tx_odd;
static bool tx_data01;

static volatile unsigned int nextaddr;

static void *tx_data;
static size_t tx_size;

struct tok_setup {
	uint8_t reqtyp;
	uint8_t req;
	uint16_t value;
	uint16_t index;
	uint16_t length;
};

/* read_setup: parse a SETUP token's data */
static void read_setup(struct tok_setup *setup, const void *_data)
{
	const unsigned char *data = _data;

	setup->reqtyp = data[0];
	setup->req = data[1];
	setup->value = le16toh(&data[2]);
	setup->index = le16toh(&data[4]);
	setup->length = le16toh(&data[6]);
}

/* TODO: Make this a shared thing across all USB endpoints */

/* puttx: place data in the current buffer descriptor */
static bool puttx(void *data, size_t size)
{
	if (GET_BIT(usb_bdt[0][BDT_TX][tx_odd].desc, BD_OWN))
		return false;

	/* TODO: Just stop bothering with const */
	usb_bdt[0][BDT_TX][tx_odd].addr = data;
	usb_bdt[0][BDT_TX][tx_odd].desc = USB0_BD_INIT(size, tx_data01);
	tx_odd = !tx_odd;
	tx_data01 = !tx_data01;

	return true;
}

/* pushtx: attempt to push rest of the current transmission into a BD */
static bool pushtx(void)
{
	size_t size = tx_size;

	if (tx_data == NULL)
		return false;

	if (size > MAX_PACKET)
		size = MAX_PACKET;

	if (!puttx(tx_data, size))
		return false;

	tx_data = (char *)tx_data + size;
	tx_size -= size;

	if (tx_size == 0 && size < MAX_PACKET)
		tx_data = NULL;

	return true;
}

/* quetx: enqueue a transmission */
static void quetx(void *data, size_t size)
{
	tx_data = data;
	tx_size = size;

	while (pushtx())
		;
}

/* usb_endpt0_disable: Disable endpoint 0 (not valid) */
void usb_endpt0_disable(void)
{
}

/* usb_endpt0_enable: Enable and reset endpoint 0 */
void usb_endpt0_enable(void)
{
	usb_bdt[0][BDT_RX][BDT_EVEN].addr = buf[0];
	usb_bdt[0][BDT_RX][BDT_EVEN].desc = USB0_BD_INIT(sizeof buf[0], 0);

	usb_bdt[0][BDT_RX][BDT_ODD].addr = buf[1];
	usb_bdt[0][BDT_RX][BDT_ODD].desc = USB0_BD_INIT(sizeof buf[1], 0);

	usb_bdt[0][BDT_TX][BDT_EVEN].addr = NULL;
	usb_bdt[0][BDT_TX][BDT_EVEN].desc = 0;

	usb_bdt[0][BDT_TX][BDT_ODD].addr = NULL;
	usb_bdt[0][BDT_TX][BDT_ODD].desc = 0;

	USB0_ENDPT(0) = BV(ENDPT_EPRXEN) | BV(ENDPT_EPTXEN) | BV(ENDPT_EPHSHK);
	nextaddr = 0;
	tx_data = NULL;
	tx_odd = 0;
	tx_data01 = 0;
}

/* trunc: truncate size_t to a limit TODO: MOVE THIS */
static inline size_t trunc(size_t val, size_t max)
{
	if (val > max)
		return max;
	return val;
}

/* tok_setup: process a setup token */
static void tok_setup(struct tok_setup *setup)
{
	switch (setup->reqtyp << 8 | setup->req) {
	case 0x0005: /* SET ADDRESS */
		nextaddr = setup->value;
		puttx(NULL, 0);
		break;
	case 0x0009: /* SET CONFIGURATION */
		usb_endpt1_enable();
		puttx(NULL, 0);
		break;
	case 0x210a: /* SET IDLE */
		puttx(NULL, 0);
		break;
	case 0x8106: /* GET INTERFACE */
	case 0x8006: /* GET DESCRIPTOR */
		switch (setup->value) {
		case 0x0100: /* DEVICE */
			quetx(ds_dev, trunc(ARRLEN(ds_dev), setup->length));
			return;
		case 0x0200: /* CONFIGURATION */
			quetx(ds_conf, trunc(ARRLEN(ds_conf), setup->length));
			return;
		case 0x0300: /* STRING 0 */
			quetx(ds_lang, trunc(ARRLEN(ds_lang), setup->length));
			return;
		case 0x0301: /* STRING 1 */
			quetx(ds_str1, trunc(ARRLEN(ds_str1), setup->length));
			return;
		case 0x2200:
			quetx(ds_hidrep, trunc(ARRLEN(ds_hidrep), setup->length));
			return;
		}
		/* fall through */
	default:
		/* We received an unexpected SETUP so we STALL the endpoint */
		SET_BIT(USB0_ENDPT(0), ENDPT_EPSTALL);
		break;
	}
}

void usb_endpt0_token(uint8_t state)
{
	volatile struct usb0_bd *bd;
	struct tok_setup setup;

	bd = &usb_bdt[0][GET_BIT(state, STAT_TX)][GET_BIT(state, STAT_ODD)];

	switch (GET_BITS(bd->desc, BD_TOK_PID)) {
	case BD_TOK_PID_OUT:
		bd->desc = USB0_BD_INIT(sizeof buf[0], 1);
		break;
	case BD_TOK_PID_IN:
		if (nextaddr) {
			USB0_ADDR = nextaddr;
			nextaddr = 0;
		}
		break;
	case BD_TOK_PID_SETUP:
		read_setup(&setup, bd->addr);
		bd->desc = USB0_BD_INIT(sizeof buf[0], 1);

		usb_bdt[0][BDT_TX][BDT_EVEN].desc = 0;
		usb_bdt[0][BDT_TX][BDT_ODD].desc = 0;
		tx_data = NULL;

		tx_data01 = 1;

		tok_setup(&setup);

		/* SETUP sets CTL_TXSUSPENDTOKENBUSY to suspend TX */
		USB0_CTL = BV(CTL_USBENSOFEN);

		break;
	}
}