xref: /netbsd-src/sys/dev/usb/auvitek_i2c.c (revision 946379e7b37692fc43f68eb0d1c10daa0a7f3b6c)
1 /* $NetBSD: auvitek_i2c.c,v 1.3 2011/10/02 16:30:58 jmcneill 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 1.3 2011/10/02 16:30:58 jmcneill Exp $");
35 
36 #include <sys/param.h>
37 #include <sys/systm.h>
38 #include <sys/device.h>
39 #include <sys/conf.h>
40 #include <sys/bus.h>
41 #include <sys/module.h>
42 
43 #include <dev/usb/usb.h>
44 #include <dev/usb/usbdi.h>
45 #include <dev/usb/usbdi_util.h>
46 #include <dev/usb/usbdevs.h>
47 
48 #include <dev/i2c/i2cvar.h>
49 
50 #include <dev/usb/auvitekreg.h>
51 #include <dev/usb/auvitekvar.h>
52 
53 /* #define AUVITEK_I2C_DEBUG */
54 
55 static int	auvitek_i2c_acquire_bus(void *, int);
56 static void	auvitek_i2c_release_bus(void *, int);
57 static int	auvitek_i2c_exec(void *, i2c_op_t, i2c_addr_t,
58 				 const void *, size_t, void *, size_t, int);
59 
60 static int	auvitek_i2c_read(struct auvitek_softc *, i2c_addr_t,
61 				 uint8_t *, size_t);
62 static int	auvitek_i2c_write(struct auvitek_softc *, i2c_addr_t,
63 				  const uint8_t *, size_t);
64 static bool	auvitek_i2c_wait(struct auvitek_softc *);
65 static bool	auvitek_i2c_wait_rdack(struct auvitek_softc *);
66 static bool	auvitek_i2c_wait_rddone(struct auvitek_softc *);
67 static bool	auvitek_i2c_wait_wrdone(struct auvitek_softc *);
68 
69 int
70 auvitek_i2c_attach(struct auvitek_softc *sc)
71 {
72 	mutex_init(&sc->sc_i2c_lock, MUTEX_DEFAULT, IPL_NONE);
73 	sc->sc_i2c.ic_cookie = sc;
74 	sc->sc_i2c.ic_acquire_bus = auvitek_i2c_acquire_bus;
75 	sc->sc_i2c.ic_release_bus = auvitek_i2c_release_bus;
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 	mutex_destroy(&sc->sc_i2c_lock);
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_type = I2C_TYPE_SMBUS;
104 		iba.iba_tag = &sc->sc_i2c;
105 		sc->sc_i2cdev = config_found_ia(sc->sc_dev, "i2cbus",
106 		    &iba, iicbus_print);
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_acquire_bus(void *opaque, int flags)
120 {
121 	struct auvitek_softc *sc = opaque;
122 
123 	if (flags & I2C_F_POLL) {
124 		if (!mutex_tryenter(&sc->sc_i2c_lock))
125 			return EBUSY;
126 	} else {
127 		mutex_enter(&sc->sc_i2c_lock);
128 	}
129 
130 	return 0;
131 }
132 
133 static void
134 auvitek_i2c_release_bus(void *opaque, int flags)
135 {
136 	struct auvitek_softc *sc = opaque;
137 
138 	mutex_exit(&sc->sc_i2c_lock);
139 }
140 
141 static int
142 auvitek_i2c_exec(void *opaque, i2c_op_t op, i2c_addr_t addr,
143     const void *cmd, size_t cmdlen, void *vbuf, size_t buflen, int flags)
144 {
145 	struct auvitek_softc *sc = opaque;
146 
147 	if (I2C_OP_READ_P(op))
148 		return auvitek_i2c_read(sc, addr, vbuf, buflen);
149 	else
150 		return auvitek_i2c_write(sc, addr, cmd, cmdlen);
151 }
152 
153 static int
154 auvitek_i2c_read(struct auvitek_softc *sc, i2c_addr_t addr,
155     uint8_t *buf, size_t buflen)
156 {
157 	uint8_t v;
158 	unsigned int i;
159 
160 	//KASSERT(mutex_owned(&sc->sc_i2c_lock));
161 
162 	auvitek_write_1(sc, AU0828_REG_I2C_MBMODE, 1);
163 	auvitek_write_1(sc, AU0828_REG_I2C_CLKDIV, sc->sc_i2c_clkdiv);
164 	auvitek_write_1(sc, AU0828_REG_I2C_DSTADDR, addr << 1);
165 
166 	if (buflen == 0) {
167 		auvitek_write_1(sc, AU0828_REG_I2C_TRIGGER,
168 		    AU0828_I2C_TRIGGER_RD);
169 		if (auvitek_i2c_wait_rdack(sc) == false)
170 			return EBUSY;
171 		return 0;
172 	}
173 
174 	for (i = 0; i < buflen; i++) {
175 		v = AU0828_I2C_TRIGGER_RD;
176 		if (i < (buflen - 1))
177 			v |= AU0828_I2C_TRIGGER_HOLD;
178 		auvitek_write_1(sc, AU0828_REG_I2C_TRIGGER, v);
179 
180 		if (auvitek_i2c_wait_rddone(sc) == false)
181 			return EBUSY;
182 
183 		buf[i] = auvitek_read_1(sc, AU0828_REG_I2C_FIFORD);
184 	}
185 
186 	if (auvitek_i2c_wait(sc) == false)
187 		return EBUSY;
188 
189 	return 0;
190 }
191 
192 static int
193 auvitek_i2c_write(struct auvitek_softc *sc, i2c_addr_t addr,
194     const uint8_t *buf, size_t buflen)
195 {
196 	uint8_t v;
197 	unsigned int i, fifolen;
198 
199 	//KASSERT(mutex_owned(&sc->sc_i2c_lock));
200 
201 	auvitek_write_1(sc, AU0828_REG_I2C_MBMODE, 1);
202 	auvitek_write_1(sc, AU0828_REG_I2C_CLKDIV, sc->sc_i2c_clkdiv);
203 	auvitek_write_1(sc, AU0828_REG_I2C_DSTADDR, addr << 1);
204 
205 	if (buflen == 0) {
206 		auvitek_write_1(sc, AU0828_REG_I2C_TRIGGER,
207 		    AU0828_I2C_TRIGGER_RD);
208 		if (auvitek_i2c_wait(sc) == false)
209 			return EBUSY;
210 		if (auvitek_i2c_wait_rdack(sc) == false)
211 			return EBUSY;
212 		return 0;
213 	}
214 
215 	fifolen = 0;
216 	for (i = 0; i < buflen; i++) {
217 		v = AU0828_I2C_TRIGGER_WR;
218 		if (i < (buflen - 1))
219 			v |= AU0828_I2C_TRIGGER_HOLD;
220 
221 		auvitek_write_1(sc, AU0828_REG_I2C_FIFOWR, buf[i]);
222 		++fifolen;
223 
224 		if (fifolen == 4 || i == (buflen - 1)) {
225 			auvitek_write_1(sc, AU0828_REG_I2C_TRIGGER, v);
226 			fifolen = 0;
227 
228 			if (auvitek_i2c_wait_wrdone(sc) == false)
229 				return EBUSY;
230 		}
231 	}
232 
233 	if (auvitek_i2c_wait(sc) == false)
234 		return EBUSY;
235 
236 	return 0;
237 }
238 
239 static bool
240 auvitek_i2c_wait(struct auvitek_softc *sc)
241 {
242 	uint8_t status;
243 	int retry = 1000;
244 
245 	while (--retry > 0) {
246 		status = auvitek_read_1(sc, AU0828_REG_I2C_STATUS);
247 		if (!(status & AU0828_I2C_STATUS_BUSY))
248 			break;
249 		delay(10);
250 	}
251 	if (retry == 0)
252 		return false;
253 
254 	return true;
255 }
256 
257 static bool
258 auvitek_i2c_wait_rdack(struct auvitek_softc *sc)
259 {
260 	uint8_t status;
261 	int retry = 1000;
262 
263 	while (--retry > 0) {
264 		status = auvitek_read_1(sc, AU0828_REG_I2C_STATUS);
265 		if (!(status & AU0828_I2C_STATUS_NO_RD_ACK))
266 			break;
267 		delay(10);
268 	}
269 	if (retry == 0)
270 		return false;
271 
272 	return true;
273 }
274 
275 static bool
276 auvitek_i2c_wait_rddone(struct auvitek_softc *sc)
277 {
278 	uint8_t status;
279 	int retry = 1000;
280 
281 	while (--retry > 0) {
282 		status = auvitek_read_1(sc, AU0828_REG_I2C_STATUS);
283 		if (status & AU0828_I2C_STATUS_RD_DONE)
284 			break;
285 		delay(10);
286 	}
287 	if (retry == 0)
288 		return false;
289 
290 	return true;
291 }
292 
293 static bool
294 auvitek_i2c_wait_wrdone(struct auvitek_softc *sc)
295 {
296 	uint8_t status;
297 	int retry = 1000;
298 
299 	while (--retry > 0) {
300 		status = auvitek_read_1(sc, AU0828_REG_I2C_STATUS);
301 		if (status & AU0828_I2C_STATUS_WR_DONE)
302 			break;
303 		delay(10);
304 	}
305 	if (retry == 0)
306 		return false;
307 
308 	return true;
309 }
310