xref: /netbsd-src/sys/arch/macppc/dev/ki2c.c (revision c2f76ff004a2cb67efe5b12d97bd3ef7fe89e18d)
1 /*	$NetBSD: ki2c.c,v 1.16 2010/12/20 00:25:37 matt Exp $	*/
2 /*	Id: ki2c.c,v 1.7 2002/10/05 09:56:05 tsubai Exp	*/
3 
4 /*-
5  * Copyright (c) 2001 Tsubai Masanari.  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  * 3. The name of the author may not be used to endorse or promote products
16  *    derived from this software without specific prior written permission.
17  *
18  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
19  * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
20  * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
21  * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
22  * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
23  * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
24  * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
25  * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
26  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
27  * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
28  */
29 
30 #include <sys/param.h>
31 #include <sys/device.h>
32 #include <sys/systm.h>
33 #include <sys/mutex.h>
34 
35 #include <dev/ofw/openfirm.h>
36 #include <machine/autoconf.h>
37 
38 #include <macppc/dev/ki2cvar.h>
39 
40 int ki2c_match(struct device *, struct cfdata *, void *);
41 void ki2c_attach(struct device *, struct device *, void *);
42 inline u_int ki2c_readreg(struct ki2c_softc *, int);
43 inline void ki2c_writereg(struct ki2c_softc *, int, u_int);
44 u_int ki2c_getmode(struct ki2c_softc *);
45 void ki2c_setmode(struct ki2c_softc *, u_int);
46 u_int ki2c_getspeed(struct ki2c_softc *);
47 void ki2c_setspeed(struct ki2c_softc *, u_int);
48 int ki2c_intr(struct ki2c_softc *);
49 int ki2c_poll(struct ki2c_softc *, int);
50 int ki2c_start(struct ki2c_softc *, int, int, void *, int);
51 int ki2c_read(struct ki2c_softc *, int, int, void *, int);
52 int ki2c_write(struct ki2c_softc *, int, int, void *, int);
53 int ki2c_print(void *, const char *);
54 
55 /* I2C glue */
56 static int ki2c_i2c_acquire_bus(void *, int);
57 static void ki2c_i2c_release_bus(void *, int);
58 static int ki2c_i2c_exec(void *, i2c_op_t, i2c_addr_t, const void *, size_t,
59 		    void *, size_t, int);
60 
61 
62 CFATTACH_DECL(ki2c, sizeof(struct ki2c_softc), ki2c_match, ki2c_attach,
63 	NULL, NULL);
64 
65 int
66 ki2c_match(struct device *parent, struct cfdata *match, void *aux)
67 {
68 	struct confargs *ca = aux;
69 
70 	if (strcmp(ca->ca_name, "i2c") == 0)
71 		return 1;
72 
73 	return 0;
74 }
75 
76 void
77 ki2c_attach(struct device *parent, struct device *self, void *aux)
78 {
79 	struct ki2c_softc *sc = (struct ki2c_softc *)self;
80 	struct confargs *ca = aux;
81 	int node = ca->ca_node;
82 	int rate, child, namelen, i2cbus;
83 	struct ki2c_confargs ka;
84 	struct i2cbus_attach_args iba;
85 
86 	char name[32];
87 	u_int reg[20];
88 
89 	ca->ca_reg[0] += ca->ca_baseaddr;
90 
91 	if (OF_getprop(node, "AAPL,i2c-rate", &rate, 4) != 4) {
92 		printf(": cannot get i2c-rate\n");
93 		return;
94 	}
95 	if (OF_getprop(node, "AAPL,address", &sc->sc_reg, 4) != 4) {
96 		printf(": unable to find i2c address\n");
97 		return;
98 	}
99 	if (OF_getprop(node, "AAPL,address-step", &sc->sc_regstep, 4) != 4) {
100 		printf(": unable to find i2c address step\n");
101 		return;
102 	}
103 
104 	printf("\n");
105 
106 	ki2c_writereg(sc, STATUS, 0);
107 	ki2c_writereg(sc, ISR, 0);
108 	ki2c_writereg(sc, IER, 0);
109 
110 	ki2c_setmode(sc, I2C_STDSUBMODE);
111 	ki2c_setspeed(sc, I2C_100kHz);		/* XXX rate */
112 
113 	mutex_init(&sc->sc_buslock, MUTEX_DEFAULT, IPL_NONE);
114 	ki2c_writereg(sc, IER,I2C_INT_DATA|I2C_INT_ADDR|I2C_INT_STOP);
115 
116 	/* fill in the i2c tag */
117 	sc->sc_i2c.ic_cookie = sc;
118 	sc->sc_i2c.ic_acquire_bus = ki2c_i2c_acquire_bus;
119 	sc->sc_i2c.ic_release_bus = ki2c_i2c_release_bus;
120 	sc->sc_i2c.ic_send_start = NULL;
121 	sc->sc_i2c.ic_send_stop = NULL;
122 	sc->sc_i2c.ic_initiate_xfer = NULL;
123 	sc->sc_i2c.ic_read_byte = NULL;
124 	sc->sc_i2c.ic_write_byte = NULL;
125 	sc->sc_i2c.ic_exec = ki2c_i2c_exec;
126 
127 	iba.iba_tag = &sc->sc_i2c;
128 	(void) config_found_ia(&sc->sc_dev, "i2cbus", &iba, iicbus_print);
129 
130 	/*
131 	 * newer OF puts I2C devices under 'i2c-bus' instead of attaching them
132 	 * directly to the ki2c node so we just check if we have a child named
133 	 * 'i2c-bus' and if so we attach its children, not ours
134 	 */
135 	i2cbus = 0;
136 	child = OF_child(node);
137 	while ((child != 0) && (i2cbus == 0)) {
138 		OF_getprop(child, "name", name, sizeof(name));
139 		if (strcmp(name, "i2c-bus") == 0)
140 			i2cbus = child;
141 		child = OF_peer(child);
142 	}
143 	if (i2cbus == 0)
144 		i2cbus = node;
145 
146 	for (child = OF_child(i2cbus); child; child = OF_peer(child)) {
147 		int ok = 0;
148 		namelen = OF_getprop(child, "name", name, sizeof(name));
149 		if (namelen < 0)
150 			continue;
151 		if (namelen >= sizeof(name))
152 			continue;
153 
154 		name[namelen] = 0;
155 		ka.ka_name = name;
156 		ka.ka_node = child;
157 		ok = OF_getprop(child, "reg", reg, sizeof(reg));
158 		if (ok <= 0) {
159 			ok = OF_getprop(child, "i2c-address", reg,
160 			    sizeof(reg));
161 		}
162 		if (ok > 0) {
163 			ka.ka_addr = reg[0];
164 			ka.ka_tag = &sc->sc_i2c;
165 			config_found_ia(self, "ki2c", &ka, ki2c_print);
166 		}
167 #ifdef DIAGNOSTIC
168 		else {
169 			printf("%s: device (%s) has no reg or i2c-address property.\n",
170 			    sc->sc_dev.dv_xname, name);
171 		}
172 #endif
173 	}
174 }
175 
176 int
177 ki2c_print(void *aux, const char *ki2c)
178 {
179 	struct ki2c_confargs *ka = aux;
180 
181 	if (ki2c) {
182 		aprint_normal("%s at %s", ka->ka_name, ki2c);
183 		aprint_normal(" address 0x%x", ka->ka_addr);
184 	}
185 	return UNCONF;
186 }
187 
188 u_int
189 ki2c_readreg(struct ki2c_softc *sc, int reg)
190 {
191 	u_char *addr = sc->sc_reg + sc->sc_regstep * reg;
192 
193 	return *addr;
194 }
195 
196 void
197 ki2c_writereg(struct ki2c_softc *sc, int reg, u_int val)
198 {
199 	u_char *addr = sc->sc_reg + sc->sc_regstep * reg;
200 
201 	*addr = val;
202 	__asm volatile ("eieio");
203 	delay(10);
204 }
205 
206 u_int
207 ki2c_getmode(struct ki2c_softc *sc)
208 {
209 	return ki2c_readreg(sc, MODE) & I2C_MODE;
210 }
211 
212 void
213 ki2c_setmode(struct ki2c_softc *sc, u_int mode)
214 {
215 	u_int x;
216 
217 	KASSERT((mode & ~I2C_MODE) == 0);
218 	x = ki2c_readreg(sc, MODE);
219 	x &= ~I2C_MODE;
220 	x |= mode;
221 	ki2c_writereg(sc, MODE, x);
222 }
223 
224 u_int
225 ki2c_getspeed(struct ki2c_softc *sc)
226 {
227 	return ki2c_readreg(sc, MODE) & I2C_SPEED;
228 }
229 
230 void
231 ki2c_setspeed(struct ki2c_softc *sc, u_int speed)
232 {
233 	u_int x;
234 
235 	KASSERT((speed & ~I2C_SPEED) == 0);
236 	x = ki2c_readreg(sc, MODE);
237 	x &= ~I2C_SPEED;
238 	x |= speed;
239 	ki2c_writereg(sc, MODE, x);
240 }
241 
242 int
243 ki2c_intr(struct ki2c_softc *sc)
244 {
245 	u_int isr, x;
246 
247 	isr = ki2c_readreg(sc, ISR);
248 	if (isr & I2C_INT_ADDR) {
249 #if 0
250 		if ((ki2c_readreg(sc, STATUS) & I2C_ST_LASTAAK) == 0) {
251 			/* No slave responded. */
252 			sc->sc_flags |= I2C_ERROR;
253 			goto out;
254 		}
255 #endif
256 
257 		if (sc->sc_flags & I2C_READING) {
258 			if (sc->sc_resid > 1) {
259 				x = ki2c_readreg(sc, CONTROL);
260 				x |= I2C_CT_AAK;
261 				ki2c_writereg(sc, CONTROL, x);
262 			}
263 		} else {
264 			ki2c_writereg(sc, DATA, *sc->sc_data++);
265 			sc->sc_resid--;
266 		}
267 	}
268 
269 	if (isr & I2C_INT_DATA) {
270 		if (sc->sc_flags & I2C_READING) {
271 			*sc->sc_data++ = ki2c_readreg(sc, DATA);
272 			sc->sc_resid--;
273 
274 			if (sc->sc_resid == 0) {	/* Completed */
275 				ki2c_writereg(sc, CONTROL, 0);
276 				goto out;
277 			}
278 		} else {
279 #if 0
280 			if ((ki2c_readreg(sc, STATUS) & I2C_ST_LASTAAK) == 0) {
281 				/* No slave responded. */
282 				sc->sc_flags |= I2C_ERROR;
283 				goto out;
284 			}
285 #endif
286 
287 			if (sc->sc_resid == 0) {
288 				x = ki2c_readreg(sc, CONTROL) | I2C_CT_STOP;
289 				ki2c_writereg(sc, CONTROL, x);
290 			} else {
291 				ki2c_writereg(sc, DATA, *sc->sc_data++);
292 				sc->sc_resid--;
293 			}
294 		}
295 	}
296 
297 out:
298 	if (isr & I2C_INT_STOP) {
299 		ki2c_writereg(sc, CONTROL, 0);
300 		sc->sc_flags &= ~I2C_BUSY;
301 	}
302 
303 	ki2c_writereg(sc, ISR, isr);
304 
305 	return 1;
306 }
307 
308 int
309 ki2c_poll(struct ki2c_softc *sc, int timo)
310 {
311 	while (sc->sc_flags & I2C_BUSY) {
312 		if (ki2c_readreg(sc, ISR))
313 			ki2c_intr(sc);
314 		timo -= 100;
315 		if (timo < 0) {
316 			printf("i2c_poll: timeout\n");
317 			return -1;
318 		}
319 		delay(100);
320 	}
321 	return 0;
322 }
323 
324 int
325 ki2c_start(struct ki2c_softc *sc, int addr, int subaddr, void *data, int len)
326 {
327 	int rw = (sc->sc_flags & I2C_READING) ? 1 : 0;
328 	int timo, x;
329 
330 	KASSERT((addr & 1) == 0);
331 
332 	sc->sc_data = data;
333 	sc->sc_resid = len;
334 	sc->sc_flags |= I2C_BUSY;
335 
336 	timo = 1000 + len * 200;
337 
338 	/* XXX TAS3001 sometimes takes 50ms to finish writing registers. */
339 	/* if (addr == 0x68) */
340 		timo += 100000;
341 
342 	ki2c_writereg(sc, ADDR, addr | rw);
343 	ki2c_writereg(sc, SUBADDR, subaddr);
344 
345 	x = ki2c_readreg(sc, CONTROL) | I2C_CT_ADDR;
346 	ki2c_writereg(sc, CONTROL, x);
347 
348 	if (ki2c_poll(sc, timo))
349 		return -1;
350 	if (sc->sc_flags & I2C_ERROR) {
351 		printf("I2C_ERROR\n");
352 		return -1;
353 	}
354 	return 0;
355 }
356 
357 int
358 ki2c_read(struct ki2c_softc *sc, int addr, int subaddr, void *data, int len)
359 {
360 	sc->sc_flags = I2C_READING;
361 	#ifdef KI2C_DEBUG
362 		printf("ki2c_read: %02x %d\n", addr, len);
363 	#endif
364 	return ki2c_start(sc, addr, subaddr, data, len);
365 }
366 
367 int
368 ki2c_write(struct ki2c_softc *sc, int addr, int subaddr, void *data, int len)
369 {
370 	sc->sc_flags = 0;
371 	#ifdef KI2C_DEBUG
372 		printf("ki2c_write: %02x %d\n",addr,len);
373 	#endif
374 	return ki2c_start(sc, addr, subaddr, data, len);
375 }
376 
377 static int
378 ki2c_i2c_acquire_bus(void *cookie, int flags)
379 {
380 	struct ki2c_softc *sc = cookie;
381 
382 	mutex_enter(&sc->sc_buslock);
383 	return 0;
384 }
385 
386 static void
387 ki2c_i2c_release_bus(void *cookie, int flags)
388 {
389 	struct ki2c_softc *sc = cookie;
390 
391 	mutex_exit(&sc->sc_buslock);
392 }
393 
394 int
395 ki2c_i2c_exec(void *cookie, i2c_op_t op, i2c_addr_t addr, const void *vcmd,
396     size_t cmdlen, void *vbuf, size_t buflen, int flags)
397 {
398 	struct ki2c_softc *sc = cookie;
399 	int i;
400 	size_t w_len;
401 	uint8_t *wp;
402 	uint8_t wrbuf[I2C_EXEC_MAX_CMDLEN + I2C_EXEC_MAX_CMDLEN];
403 
404 	/*
405 	 * We don't have any idea if the ki2c controller can execute
406 	 * i2c quick_{read,write} operations, so if someone tries one,
407 	 * return an error.
408 	 */
409 	if (cmdlen == 0 && buflen == 0)
410 		return -1;
411 
412 	/* we handle the subaddress stuff ourselves */
413 	ki2c_setmode(sc, I2C_STDMODE);
414 
415 	/* Write-buffer defaults to vcmd */
416 	wp = (uint8_t *)(__UNCONST(vcmd));
417 	w_len = cmdlen;
418 
419 	/*
420 	 * Concatenate vcmd and vbuf for write operations
421 	 *
422 	 * Drivers written specifically for ki2c might already do this,
423 	 * but "generic" i2c drivers still provide separate arguments
424 	 * for the cmd and buf parts of iic_smbus_write_{byte,word}.
425 	 */
426 	if (I2C_OP_WRITE_P(op) && buflen != 0) {
427 		if (cmdlen == 0) {
428 			wp = (uint8_t *)vbuf;
429 			w_len = buflen;
430 		} else {
431 			KASSERT((cmdlen + buflen) <= sizeof(wrbuf));
432 			wp = (uint8_t *)(__UNCONST(vcmd));
433 			w_len = 0;
434 			for (i = 0; i < cmdlen; i++)
435 				wrbuf[w_len++] = *wp++;
436 			wp = (uint8_t *)vbuf;
437 			for (i = 0; i < buflen; i++)
438 				wrbuf[w_len++] = *wp++;
439 			wp = wrbuf;
440 		}
441 	}
442 
443 	if (ki2c_write(sc, addr, 0, wp, w_len) !=0 )
444 		return -1;
445 
446 	if (I2C_OP_READ_P(op)) {
447 		if (ki2c_read(sc, addr, 0, vbuf, buflen) !=0 )
448 			return -1;
449 	}
450 	return 0;
451 }
452