1/*	$NetBSD: ki2c.c,v 1.17 2011/06/18 08:08:28 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
40int ki2c_match(device_t, cfdata_t, void *);
41void ki2c_attach(device_t, device_t, void *);
42inline u_int ki2c_readreg(struct ki2c_softc *, int);
43inline void ki2c_writereg(struct ki2c_softc *, int, u_int);
44u_int ki2c_getmode(struct ki2c_softc *);
45void ki2c_setmode(struct ki2c_softc *, u_int);
46u_int ki2c_getspeed(struct ki2c_softc *);
47void ki2c_setspeed(struct ki2c_softc *, u_int);
48int ki2c_intr(struct ki2c_softc *);
49int ki2c_poll(struct ki2c_softc *, int);
50int ki2c_start(struct ki2c_softc *, int, int, void *, int);
51int ki2c_read(struct ki2c_softc *, int, int, void *, int);
52int ki2c_write(struct ki2c_softc *, int, int, void *, int);
53int ki2c_print(void *, const char *);
54
55/* I2C glue */
56static int ki2c_i2c_acquire_bus(void *, int);
57static void ki2c_i2c_release_bus(void *, int);
58static int ki2c_i2c_exec(void *, i2c_op_t, i2c_addr_t, const void *, size_t,
59		    void *, size_t, int);
60
61
62CFATTACH_DECL_NEW(ki2c, sizeof(struct ki2c_softc), ki2c_match, ki2c_attach,
63	NULL, NULL);
64
65int
66ki2c_match(device_t parent, cfdata_t 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
76void
77ki2c_attach(device_t parent, device_t self, void *aux)
78{
79	struct ki2c_softc *sc = device_private(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	sc->sc_dev = self;
90	ca->ca_reg[0] += ca->ca_baseaddr;
91
92	if (OF_getprop(node, "AAPL,i2c-rate", &rate, 4) != 4) {
93		printf(": cannot get i2c-rate\n");
94		return;
95	}
96	if (OF_getprop(node, "AAPL,address", &sc->sc_reg, 4) != 4) {
97		printf(": unable to find i2c address\n");
98		return;
99	}
100	if (OF_getprop(node, "AAPL,address-step", &sc->sc_regstep, 4) != 4) {
101		printf(": unable to find i2c address step\n");
102		return;
103	}
104
105	printf("\n");
106
107	ki2c_writereg(sc, STATUS, 0);
108	ki2c_writereg(sc, ISR, 0);
109	ki2c_writereg(sc, IER, 0);
110
111	ki2c_setmode(sc, I2C_STDSUBMODE);
112	ki2c_setspeed(sc, I2C_100kHz);		/* XXX rate */
113
114	mutex_init(&sc->sc_buslock, MUTEX_DEFAULT, IPL_NONE);
115	ki2c_writereg(sc, IER,I2C_INT_DATA|I2C_INT_ADDR|I2C_INT_STOP);
116
117	/* fill in the i2c tag */
118	sc->sc_i2c.ic_cookie = sc;
119	sc->sc_i2c.ic_acquire_bus = ki2c_i2c_acquire_bus;
120	sc->sc_i2c.ic_release_bus = ki2c_i2c_release_bus;
121	sc->sc_i2c.ic_send_start = NULL;
122	sc->sc_i2c.ic_send_stop = NULL;
123	sc->sc_i2c.ic_initiate_xfer = NULL;
124	sc->sc_i2c.ic_read_byte = NULL;
125	sc->sc_i2c.ic_write_byte = NULL;
126	sc->sc_i2c.ic_exec = ki2c_i2c_exec;
127
128	iba.iba_tag = &sc->sc_i2c;
129	(void) config_found_ia(sc->sc_dev, "i2cbus", &iba, iicbus_print);
130
131	/*
132	 * newer OF puts I2C devices under 'i2c-bus' instead of attaching them
133	 * directly to the ki2c node so we just check if we have a child named
134	 * 'i2c-bus' and if so we attach its children, not ours
135	 */
136	i2cbus = 0;
137	child = OF_child(node);
138	while ((child != 0) && (i2cbus == 0)) {
139		OF_getprop(child, "name", name, sizeof(name));
140		if (strcmp(name, "i2c-bus") == 0)
141			i2cbus = child;
142		child = OF_peer(child);
143	}
144	if (i2cbus == 0)
145		i2cbus = node;
146
147	for (child = OF_child(i2cbus); child; child = OF_peer(child)) {
148		int ok = 0;
149		namelen = OF_getprop(child, "name", name, sizeof(name));
150		if (namelen < 0)
151			continue;
152		if (namelen >= sizeof(name))
153			continue;
154
155		name[namelen] = 0;
156		ka.ka_name = name;
157		ka.ka_node = child;
158		ok = OF_getprop(child, "reg", reg, sizeof(reg));
159		if (ok <= 0) {
160			ok = OF_getprop(child, "i2c-address", reg,
161			    sizeof(reg));
162		}
163		if (ok > 0) {
164			ka.ka_addr = reg[0];
165			ka.ka_tag = &sc->sc_i2c;
166			config_found_ia(self, "ki2c", &ka, ki2c_print);
167		}
168#ifdef DIAGNOSTIC
169		else {
170			printf("%s: device (%s) has no reg or i2c-address property.\n",
171			    device_xname(sc->sc_dev), name);
172		}
173#endif
174	}
175}
176
177int
178ki2c_print(void *aux, const char *ki2c)
179{
180	struct ki2c_confargs *ka = aux;
181
182	if (ki2c) {
183		aprint_normal("%s at %s", ka->ka_name, ki2c);
184		aprint_normal(" address 0x%x", ka->ka_addr);
185	}
186	return UNCONF;
187}
188
189u_int
190ki2c_readreg(struct ki2c_softc *sc, int reg)
191{
192	u_char *addr = sc->sc_reg + sc->sc_regstep * reg;
193
194	return *addr;
195}
196
197void
198ki2c_writereg(struct ki2c_softc *sc, int reg, u_int val)
199{
200	u_char *addr = sc->sc_reg + sc->sc_regstep * reg;
201
202	*addr = val;
203	__asm volatile ("eieio");
204	delay(10);
205}
206
207u_int
208ki2c_getmode(struct ki2c_softc *sc)
209{
210	return ki2c_readreg(sc, MODE) & I2C_MODE;
211}
212
213void
214ki2c_setmode(struct ki2c_softc *sc, u_int mode)
215{
216	u_int x;
217
218	KASSERT((mode & ~I2C_MODE) == 0);
219	x = ki2c_readreg(sc, MODE);
220	x &= ~I2C_MODE;
221	x |= mode;
222	ki2c_writereg(sc, MODE, x);
223}
224
225u_int
226ki2c_getspeed(struct ki2c_softc *sc)
227{
228	return ki2c_readreg(sc, MODE) & I2C_SPEED;
229}
230
231void
232ki2c_setspeed(struct ki2c_softc *sc, u_int speed)
233{
234	u_int x;
235
236	KASSERT((speed & ~I2C_SPEED) == 0);
237	x = ki2c_readreg(sc, MODE);
238	x &= ~I2C_SPEED;
239	x |= speed;
240	ki2c_writereg(sc, MODE, x);
241}
242
243int
244ki2c_intr(struct ki2c_softc *sc)
245{
246	u_int isr, x;
247
248	isr = ki2c_readreg(sc, ISR);
249	if (isr & I2C_INT_ADDR) {
250#if 0
251		if ((ki2c_readreg(sc, STATUS) & I2C_ST_LASTAAK) == 0) {
252			/* No slave responded. */
253			sc->sc_flags |= I2C_ERROR;
254			goto out;
255		}
256#endif
257
258		if (sc->sc_flags & I2C_READING) {
259			if (sc->sc_resid > 1) {
260				x = ki2c_readreg(sc, CONTROL);
261				x |= I2C_CT_AAK;
262				ki2c_writereg(sc, CONTROL, x);
263			}
264		} else {
265			ki2c_writereg(sc, DATA, *sc->sc_data++);
266			sc->sc_resid--;
267		}
268	}
269
270	if (isr & I2C_INT_DATA) {
271		if (sc->sc_flags & I2C_READING) {
272			*sc->sc_data++ = ki2c_readreg(sc, DATA);
273			sc->sc_resid--;
274
275			if (sc->sc_resid == 0) {	/* Completed */
276				ki2c_writereg(sc, CONTROL, 0);
277				goto out;
278			}
279		} else {
280#if 0
281			if ((ki2c_readreg(sc, STATUS) & I2C_ST_LASTAAK) == 0) {
282				/* No slave responded. */
283				sc->sc_flags |= I2C_ERROR;
284				goto out;
285			}
286#endif
287
288			if (sc->sc_resid == 0) {
289				x = ki2c_readreg(sc, CONTROL) | I2C_CT_STOP;
290				ki2c_writereg(sc, CONTROL, x);
291			} else {
292				ki2c_writereg(sc, DATA, *sc->sc_data++);
293				sc->sc_resid--;
294			}
295		}
296	}
297
298out:
299	if (isr & I2C_INT_STOP) {
300		ki2c_writereg(sc, CONTROL, 0);
301		sc->sc_flags &= ~I2C_BUSY;
302	}
303
304	ki2c_writereg(sc, ISR, isr);
305
306	return 1;
307}
308
309int
310ki2c_poll(struct ki2c_softc *sc, int timo)
311{
312	while (sc->sc_flags & I2C_BUSY) {
313		if (ki2c_readreg(sc, ISR))
314			ki2c_intr(sc);
315		timo -= 100;
316		if (timo < 0) {
317			printf("i2c_poll: timeout\n");
318			return -1;
319		}
320		delay(100);
321	}
322	return 0;
323}
324
325int
326ki2c_start(struct ki2c_softc *sc, int addr, int subaddr, void *data, int len)
327{
328	int rw = (sc->sc_flags & I2C_READING) ? 1 : 0;
329	int timo, x;
330
331	KASSERT((addr & 1) == 0);
332
333	sc->sc_data = data;
334	sc->sc_resid = len;
335	sc->sc_flags |= I2C_BUSY;
336
337	timo = 1000 + len * 200;
338
339	/* XXX TAS3001 sometimes takes 50ms to finish writing registers. */
340	/* if (addr == 0x68) */
341		timo += 100000;
342
343	ki2c_writereg(sc, ADDR, addr | rw);
344	ki2c_writereg(sc, SUBADDR, subaddr);
345
346	x = ki2c_readreg(sc, CONTROL) | I2C_CT_ADDR;
347	ki2c_writereg(sc, CONTROL, x);
348
349	if (ki2c_poll(sc, timo))
350		return -1;
351	if (sc->sc_flags & I2C_ERROR) {
352		printf("I2C_ERROR\n");
353		return -1;
354	}
355	return 0;
356}
357
358int
359ki2c_read(struct ki2c_softc *sc, int addr, int subaddr, void *data, int len)
360{
361	sc->sc_flags = I2C_READING;
362	#ifdef KI2C_DEBUG
363		printf("ki2c_read: %02x %d\n", addr, len);
364	#endif
365	return ki2c_start(sc, addr, subaddr, data, len);
366}
367
368int
369ki2c_write(struct ki2c_softc *sc, int addr, int subaddr, void *data, int len)
370{
371	sc->sc_flags = 0;
372	#ifdef KI2C_DEBUG
373		printf("ki2c_write: %02x %d\n",addr,len);
374	#endif
375	return ki2c_start(sc, addr, subaddr, data, len);
376}
377
378static int
379ki2c_i2c_acquire_bus(void *cookie, int flags)
380{
381	struct ki2c_softc *sc = cookie;
382
383	mutex_enter(&sc->sc_buslock);
384	return 0;
385}
386
387static void
388ki2c_i2c_release_bus(void *cookie, int flags)
389{
390	struct ki2c_softc *sc = cookie;
391
392	mutex_exit(&sc->sc_buslock);
393}
394
395int
396ki2c_i2c_exec(void *cookie, i2c_op_t op, i2c_addr_t addr, const void *vcmd,
397    size_t cmdlen, void *vbuf, size_t buflen, int flags)
398{
399	struct ki2c_softc *sc = cookie;
400	int i;
401	size_t w_len;
402	uint8_t *wp;
403	uint8_t wrbuf[I2C_EXEC_MAX_CMDLEN + I2C_EXEC_MAX_CMDLEN];
404
405	/*
406	 * We don't have any idea if the ki2c controller can execute
407	 * i2c quick_{read,write} operations, so if someone tries one,
408	 * return an error.
409	 */
410	if (cmdlen == 0 && buflen == 0)
411		return -1;
412
413	/* we handle the subaddress stuff ourselves */
414	ki2c_setmode(sc, I2C_STDMODE);
415
416	/* Write-buffer defaults to vcmd */
417	wp = (uint8_t *)(__UNCONST(vcmd));
418	w_len = cmdlen;
419
420	/*
421	 * Concatenate vcmd and vbuf for write operations
422	 *
423	 * Drivers written specifically for ki2c might already do this,
424	 * but "generic" i2c drivers still provide separate arguments
425	 * for the cmd and buf parts of iic_smbus_write_{byte,word}.
426	 */
427	if (I2C_OP_WRITE_P(op) && buflen != 0) {
428		if (cmdlen == 0) {
429			wp = (uint8_t *)vbuf;
430			w_len = buflen;
431		} else {
432			KASSERT((cmdlen + buflen) <= sizeof(wrbuf));
433			wp = (uint8_t *)(__UNCONST(vcmd));
434			w_len = 0;
435			for (i = 0; i < cmdlen; i++)
436				wrbuf[w_len++] = *wp++;
437			wp = (uint8_t *)vbuf;
438			for (i = 0; i < buflen; i++)
439				wrbuf[w_len++] = *wp++;
440			wp = wrbuf;
441		}
442	}
443
444	if (ki2c_write(sc, addr, 0, wp, w_len) !=0 )
445		return -1;
446
447	if (I2C_OP_READ_P(op)) {
448		if (ki2c_read(sc, addr, 0, vbuf, buflen) !=0 )
449			return -1;
450	}
451	return 0;
452}
453