xref: /netbsd-src/sys/dev/usb/auvitek_i2c.c (revision bdc22b2e01993381dcefeff2bc9b56ca75a4235c)
1 /* $NetBSD: auvitek_i2c.c,v 1.4 2016/11/25 12:56:29 skrll 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 1.4 2016/11/25 12:56:29 skrll 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_acquire_bus(void *, int);
60 static void	auvitek_i2c_release_bus(void *, int);
61 static int	auvitek_i2c_exec(void *, i2c_op_t, i2c_addr_t,
62 				 const void *, size_t, void *, size_t, int);
63 
64 static int	auvitek_i2c_read(struct auvitek_softc *, i2c_addr_t,
65 				 uint8_t *, size_t);
66 static int	auvitek_i2c_write(struct auvitek_softc *, i2c_addr_t,
67 				  const uint8_t *, size_t);
68 static bool	auvitek_i2c_wait(struct auvitek_softc *);
69 static bool	auvitek_i2c_wait_rdack(struct auvitek_softc *);
70 static bool	auvitek_i2c_wait_rddone(struct auvitek_softc *);
71 static bool	auvitek_i2c_wait_wrdone(struct auvitek_softc *);
72 
73 int
74 auvitek_i2c_attach(struct auvitek_softc *sc)
75 {
76 	mutex_init(&sc->sc_i2c_lock, MUTEX_DEFAULT, IPL_NONE);
77 	sc->sc_i2c.ic_cookie = sc;
78 	sc->sc_i2c.ic_acquire_bus = auvitek_i2c_acquire_bus;
79 	sc->sc_i2c.ic_release_bus = auvitek_i2c_release_bus;
80 	sc->sc_i2c.ic_exec = auvitek_i2c_exec;
81 
82 	auvitek_i2c_rescan(sc, NULL, NULL);
83 
84 	return 0;
85 }
86 
87 int
88 auvitek_i2c_detach(struct auvitek_softc *sc, int flags)
89 {
90 	mutex_destroy(&sc->sc_i2c_lock);
91 
92 	if (sc->sc_i2cdev)
93 		config_detach(sc->sc_i2cdev, flags);
94 
95 	return 0;
96 }
97 
98 void
99 auvitek_i2c_rescan(struct auvitek_softc *sc, const char *ifattr,
100     const int *locs)
101 {
102 #ifdef AUVITEK_I2C_DEBUG
103 	struct i2cbus_attach_args iba;
104 
105 	if (ifattr_match(ifattr, "i2cbus") && sc->sc_i2cdev == NULL) {
106 		memset(&iba, 0, sizeof(iba));
107 		iba.iba_type = I2C_TYPE_SMBUS;
108 		iba.iba_tag = &sc->sc_i2c;
109 		sc->sc_i2cdev = config_found_ia(sc->sc_dev, "i2cbus",
110 		    &iba, iicbus_print);
111 	}
112 #endif
113 }
114 
115 void
116 auvitek_i2c_childdet(struct auvitek_softc *sc, device_t child)
117 {
118 	if (sc->sc_i2cdev == child)
119 		sc->sc_i2cdev = NULL;
120 }
121 
122 static int
123 auvitek_i2c_acquire_bus(void *opaque, int flags)
124 {
125 	struct auvitek_softc *sc = opaque;
126 
127 	if (flags & I2C_F_POLL) {
128 		if (!mutex_tryenter(&sc->sc_i2c_lock))
129 			return EBUSY;
130 	} else {
131 		mutex_enter(&sc->sc_i2c_lock);
132 	}
133 
134 	return 0;
135 }
136 
137 static void
138 auvitek_i2c_release_bus(void *opaque, int flags)
139 {
140 	struct auvitek_softc *sc = opaque;
141 
142 	mutex_exit(&sc->sc_i2c_lock);
143 }
144 
145 static int
146 auvitek_i2c_exec(void *opaque, i2c_op_t op, i2c_addr_t addr,
147     const void *cmd, size_t cmdlen, void *vbuf, size_t buflen, int flags)
148 {
149 	struct auvitek_softc *sc = opaque;
150 
151 	if (I2C_OP_READ_P(op))
152 		return auvitek_i2c_read(sc, addr, vbuf, buflen);
153 	else
154 		return auvitek_i2c_write(sc, addr, cmd, cmdlen);
155 }
156 
157 static int
158 auvitek_i2c_read(struct auvitek_softc *sc, i2c_addr_t addr,
159     uint8_t *buf, size_t buflen)
160 {
161 	uint8_t v;
162 	unsigned int i;
163 
164 	//KASSERT(mutex_owned(&sc->sc_i2c_lock));
165 
166 	auvitek_write_1(sc, AU0828_REG_I2C_MBMODE, 1);
167 	auvitek_write_1(sc, AU0828_REG_I2C_CLKDIV, sc->sc_i2c_clkdiv);
168 	auvitek_write_1(sc, AU0828_REG_I2C_DSTADDR, addr << 1);
169 
170 	if (buflen == 0) {
171 		auvitek_write_1(sc, AU0828_REG_I2C_TRIGGER,
172 		    AU0828_I2C_TRIGGER_RD);
173 		if (auvitek_i2c_wait_rdack(sc) == false)
174 			return EBUSY;
175 		return 0;
176 	}
177 
178 	for (i = 0; i < buflen; i++) {
179 		v = AU0828_I2C_TRIGGER_RD;
180 		if (i < (buflen - 1))
181 			v |= AU0828_I2C_TRIGGER_HOLD;
182 		auvitek_write_1(sc, AU0828_REG_I2C_TRIGGER, v);
183 
184 		if (auvitek_i2c_wait_rddone(sc) == false)
185 			return EBUSY;
186 
187 		buf[i] = auvitek_read_1(sc, AU0828_REG_I2C_FIFORD);
188 	}
189 
190 	if (auvitek_i2c_wait(sc) == false)
191 		return EBUSY;
192 
193 	return 0;
194 }
195 
196 static int
197 auvitek_i2c_write(struct auvitek_softc *sc, i2c_addr_t addr,
198     const uint8_t *buf, size_t buflen)
199 {
200 	uint8_t v;
201 	unsigned int i, fifolen;
202 
203 	//KASSERT(mutex_owned(&sc->sc_i2c_lock));
204 
205 	auvitek_write_1(sc, AU0828_REG_I2C_MBMODE, 1);
206 	auvitek_write_1(sc, AU0828_REG_I2C_CLKDIV, sc->sc_i2c_clkdiv);
207 	auvitek_write_1(sc, AU0828_REG_I2C_DSTADDR, addr << 1);
208 
209 	if (buflen == 0) {
210 		auvitek_write_1(sc, AU0828_REG_I2C_TRIGGER,
211 		    AU0828_I2C_TRIGGER_RD);
212 		if (auvitek_i2c_wait(sc) == false)
213 			return EBUSY;
214 		if (auvitek_i2c_wait_rdack(sc) == false)
215 			return EBUSY;
216 		return 0;
217 	}
218 
219 	fifolen = 0;
220 	for (i = 0; i < buflen; i++) {
221 		v = AU0828_I2C_TRIGGER_WR;
222 		if (i < (buflen - 1))
223 			v |= AU0828_I2C_TRIGGER_HOLD;
224 
225 		auvitek_write_1(sc, AU0828_REG_I2C_FIFOWR, buf[i]);
226 		++fifolen;
227 
228 		if (fifolen == 4 || i == (buflen - 1)) {
229 			auvitek_write_1(sc, AU0828_REG_I2C_TRIGGER, v);
230 			fifolen = 0;
231 
232 			if (auvitek_i2c_wait_wrdone(sc) == false)
233 				return EBUSY;
234 		}
235 	}
236 
237 	if (auvitek_i2c_wait(sc) == false)
238 		return EBUSY;
239 
240 	return 0;
241 }
242 
243 static bool
244 auvitek_i2c_wait(struct auvitek_softc *sc)
245 {
246 	uint8_t status;
247 	int retry = 1000;
248 
249 	while (--retry > 0) {
250 		status = auvitek_read_1(sc, AU0828_REG_I2C_STATUS);
251 		if (!(status & AU0828_I2C_STATUS_BUSY))
252 			break;
253 		delay(10);
254 	}
255 	if (retry == 0)
256 		return false;
257 
258 	return true;
259 }
260 
261 static bool
262 auvitek_i2c_wait_rdack(struct auvitek_softc *sc)
263 {
264 	uint8_t status;
265 	int retry = 1000;
266 
267 	while (--retry > 0) {
268 		status = auvitek_read_1(sc, AU0828_REG_I2C_STATUS);
269 		if (!(status & AU0828_I2C_STATUS_NO_RD_ACK))
270 			break;
271 		delay(10);
272 	}
273 	if (retry == 0)
274 		return false;
275 
276 	return true;
277 }
278 
279 static bool
280 auvitek_i2c_wait_rddone(struct auvitek_softc *sc)
281 {
282 	uint8_t status;
283 	int retry = 1000;
284 
285 	while (--retry > 0) {
286 		status = auvitek_read_1(sc, AU0828_REG_I2C_STATUS);
287 		if (status & AU0828_I2C_STATUS_RD_DONE)
288 			break;
289 		delay(10);
290 	}
291 	if (retry == 0)
292 		return false;
293 
294 	return true;
295 }
296 
297 static bool
298 auvitek_i2c_wait_wrdone(struct auvitek_softc *sc)
299 {
300 	uint8_t status;
301 	int retry = 1000;
302 
303 	while (--retry > 0) {
304 		status = auvitek_read_1(sc, AU0828_REG_I2C_STATUS);
305 		if (status & AU0828_I2C_STATUS_WR_DONE)
306 			break;
307 		delay(10);
308 	}
309 	if (retry == 0)
310 		return false;
311 
312 	return true;
313 }
314