xref: /netbsd-src/sys/dev/usb/auvitek_i2c.c (revision 82d56013d7b633d116a93943de88e08335357a7c)
1 /* $NetBSD: auvitek_i2c.c,v 1.6 2021/04/24 23:36:59 thorpej Exp $ */
2 
3 /*-
4  * Copyright (c) 2010 Jared D. McNeill <jmcneill@invisible.ca>
5  * All rights reserved.
6  *
7  * Redistribution and use in source and binary forms, with or without
8  * modification, are permitted provided that the following conditions
9  * are met:
10  * 1. Redistributions of source code must retain the above copyright
11  *    notice, this list of conditions and the following disclaimer.
12  * 2. Redistributions in binary form must reproduce the above copyright
13  *    notice, this list of conditions and the following disclaimer in the
14  *    documentation and/or other materials provided with the distribution.
15  *
16  * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS
17  * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
18  * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
19  * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS
20  * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
21  * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
22  * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
23  * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
24  * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
25  * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
26  * POSSIBILITY OF SUCH DAMAGE.
27  */
28 
29 /*
30  * Auvitek AU0828 USB controller - I2C access ops
31  */
32 
33 #include <sys/cdefs.h>
34 __KERNEL_RCSID(0, "$NetBSD: auvitek_i2c.c,v 1.6 2021/04/24 23:36:59 thorpej Exp $");
35 
36 #ifdef _KERNEL_OPT
37 #include "opt_usb.h"
38 #endif
39 
40 #include <sys/param.h>
41 #include <sys/systm.h>
42 #include <sys/device.h>
43 #include <sys/conf.h>
44 #include <sys/bus.h>
45 #include <sys/module.h>
46 
47 #include <dev/usb/usb.h>
48 #include <dev/usb/usbdi.h>
49 #include <dev/usb/usbdi_util.h>
50 #include <dev/usb/usbdevs.h>
51 
52 #include <dev/i2c/i2cvar.h>
53 
54 #include <dev/usb/auvitekreg.h>
55 #include <dev/usb/auvitekvar.h>
56 
57 /* #define AUVITEK_I2C_DEBUG */
58 
59 static int	auvitek_i2c_exec(void *, i2c_op_t, i2c_addr_t,
60 				 const void *, size_t, void *, size_t, int);
61 
62 static int	auvitek_i2c_read(struct auvitek_softc *, i2c_addr_t,
63 				 uint8_t *, size_t);
64 static int	auvitek_i2c_write(struct auvitek_softc *, i2c_addr_t,
65 				  const uint8_t *, size_t);
66 static bool	auvitek_i2c_wait(struct auvitek_softc *);
67 static bool	auvitek_i2c_wait_rdack(struct auvitek_softc *);
68 static bool	auvitek_i2c_wait_rddone(struct auvitek_softc *);
69 static bool	auvitek_i2c_wait_wrdone(struct auvitek_softc *);
70 
71 int
72 auvitek_i2c_attach(struct auvitek_softc *sc)
73 {
74 	iic_tag_init(&sc->sc_i2c);
75 	sc->sc_i2c.ic_cookie = sc;
76 	sc->sc_i2c.ic_exec = auvitek_i2c_exec;
77 
78 	auvitek_i2c_rescan(sc, NULL, NULL);
79 
80 	return 0;
81 }
82 
83 int
84 auvitek_i2c_detach(struct auvitek_softc *sc, int flags)
85 {
86 	iic_tag_fini(&sc->sc_i2c);
87 
88 	if (sc->sc_i2cdev)
89 		config_detach(sc->sc_i2cdev, flags);
90 
91 	return 0;
92 }
93 
94 void
95 auvitek_i2c_rescan(struct auvitek_softc *sc, const char *ifattr,
96     const int *locs)
97 {
98 #ifdef AUVITEK_I2C_DEBUG
99 	struct i2cbus_attach_args iba;
100 
101 	if (ifattr_match(ifattr, "i2cbus") && sc->sc_i2cdev == NULL) {
102 		memset(&iba, 0, sizeof(iba));
103 		iba.iba_tag = &sc->sc_i2c;
104 		sc->sc_i2cdev = config_found(sc->sc_dev, &iba, iicbus_print,
105 		    CFARG_IATTR, "i2cbus",
106 		    CFARG_EOL);
107 	}
108 #endif
109 }
110 
111 void
112 auvitek_i2c_childdet(struct auvitek_softc *sc, device_t child)
113 {
114 	if (sc->sc_i2cdev == child)
115 		sc->sc_i2cdev = NULL;
116 }
117 
118 static int
119 auvitek_i2c_exec(void *opaque, i2c_op_t op, i2c_addr_t addr,
120     const void *cmd, size_t cmdlen, void *vbuf, size_t buflen, int flags)
121 {
122 	struct auvitek_softc *sc = opaque;
123 
124 	if (I2C_OP_READ_P(op))
125 		return auvitek_i2c_read(sc, addr, vbuf, buflen);
126 	else
127 		return auvitek_i2c_write(sc, addr, cmd, cmdlen);
128 }
129 
130 static int
131 auvitek_i2c_read(struct auvitek_softc *sc, i2c_addr_t addr,
132     uint8_t *buf, size_t buflen)
133 {
134 	uint8_t v;
135 	unsigned int i;
136 
137 	auvitek_write_1(sc, AU0828_REG_I2C_MBMODE, 1);
138 	auvitek_write_1(sc, AU0828_REG_I2C_CLKDIV, sc->sc_i2c_clkdiv);
139 	auvitek_write_1(sc, AU0828_REG_I2C_DSTADDR, addr << 1);
140 
141 	if (buflen == 0) {
142 		auvitek_write_1(sc, AU0828_REG_I2C_TRIGGER,
143 		    AU0828_I2C_TRIGGER_RD);
144 		if (auvitek_i2c_wait_rdack(sc) == false)
145 			return EBUSY;
146 		return 0;
147 	}
148 
149 	for (i = 0; i < buflen; i++) {
150 		v = AU0828_I2C_TRIGGER_RD;
151 		if (i < (buflen - 1))
152 			v |= AU0828_I2C_TRIGGER_HOLD;
153 		auvitek_write_1(sc, AU0828_REG_I2C_TRIGGER, v);
154 
155 		if (auvitek_i2c_wait_rddone(sc) == false)
156 			return EBUSY;
157 
158 		buf[i] = auvitek_read_1(sc, AU0828_REG_I2C_FIFORD);
159 	}
160 
161 	if (auvitek_i2c_wait(sc) == false)
162 		return EBUSY;
163 
164 	return 0;
165 }
166 
167 static int
168 auvitek_i2c_write(struct auvitek_softc *sc, i2c_addr_t addr,
169     const uint8_t *buf, size_t buflen)
170 {
171 	uint8_t v;
172 	unsigned int i, fifolen;
173 
174 	auvitek_write_1(sc, AU0828_REG_I2C_MBMODE, 1);
175 	auvitek_write_1(sc, AU0828_REG_I2C_CLKDIV, sc->sc_i2c_clkdiv);
176 	auvitek_write_1(sc, AU0828_REG_I2C_DSTADDR, addr << 1);
177 
178 	if (buflen == 0) {
179 		auvitek_write_1(sc, AU0828_REG_I2C_TRIGGER,
180 		    AU0828_I2C_TRIGGER_RD);
181 		if (auvitek_i2c_wait(sc) == false)
182 			return EBUSY;
183 		if (auvitek_i2c_wait_rdack(sc) == false)
184 			return EBUSY;
185 		return 0;
186 	}
187 
188 	fifolen = 0;
189 	for (i = 0; i < buflen; i++) {
190 		v = AU0828_I2C_TRIGGER_WR;
191 		if (i < (buflen - 1))
192 			v |= AU0828_I2C_TRIGGER_HOLD;
193 
194 		auvitek_write_1(sc, AU0828_REG_I2C_FIFOWR, buf[i]);
195 		++fifolen;
196 
197 		if (fifolen == 4 || i == (buflen - 1)) {
198 			auvitek_write_1(sc, AU0828_REG_I2C_TRIGGER, v);
199 			fifolen = 0;
200 
201 			if (auvitek_i2c_wait_wrdone(sc) == false)
202 				return EBUSY;
203 		}
204 	}
205 
206 	if (auvitek_i2c_wait(sc) == false)
207 		return EBUSY;
208 
209 	return 0;
210 }
211 
212 static bool
213 auvitek_i2c_wait(struct auvitek_softc *sc)
214 {
215 	uint8_t status;
216 	int retry = 1000;
217 
218 	while (--retry > 0) {
219 		status = auvitek_read_1(sc, AU0828_REG_I2C_STATUS);
220 		if (!(status & AU0828_I2C_STATUS_BUSY))
221 			break;
222 		delay(10);
223 	}
224 	if (retry == 0)
225 		return false;
226 
227 	return true;
228 }
229 
230 static bool
231 auvitek_i2c_wait_rdack(struct auvitek_softc *sc)
232 {
233 	uint8_t status;
234 	int retry = 1000;
235 
236 	while (--retry > 0) {
237 		status = auvitek_read_1(sc, AU0828_REG_I2C_STATUS);
238 		if (!(status & AU0828_I2C_STATUS_NO_RD_ACK))
239 			break;
240 		delay(10);
241 	}
242 	if (retry == 0)
243 		return false;
244 
245 	return true;
246 }
247 
248 static bool
249 auvitek_i2c_wait_rddone(struct auvitek_softc *sc)
250 {
251 	uint8_t status;
252 	int retry = 1000;
253 
254 	while (--retry > 0) {
255 		status = auvitek_read_1(sc, AU0828_REG_I2C_STATUS);
256 		if (status & AU0828_I2C_STATUS_RD_DONE)
257 			break;
258 		delay(10);
259 	}
260 	if (retry == 0)
261 		return false;
262 
263 	return true;
264 }
265 
266 static bool
267 auvitek_i2c_wait_wrdone(struct auvitek_softc *sc)
268 {
269 	uint8_t status;
270 	int retry = 1000;
271 
272 	while (--retry > 0) {
273 		status = auvitek_read_1(sc, AU0828_REG_I2C_STATUS);
274 		if (status & AU0828_I2C_STATUS_WR_DONE)
275 			break;
276 		delay(10);
277 	}
278 	if (retry == 0)
279 		return false;
280 
281 	return true;
282 }
283