xref: /freebsd/sys/dev/iicbus/controller/rockchip/rk_i2c.c (revision 7fdf597e96a02165cfe22ff357b857d5fa15ed8a)
1 /*-
2  * SPDX-License-Identifier: BSD-2-Clause
3  *
4  * Copyright (c) 2018 Emmanuel Vadot <manu@FreeBSD.org>
5  *
6  * Redistribution and use in source and binary forms, with or without
7  * modification, are permitted provided that the following conditions
8  * are met:
9  * 1. Redistributions of source code must retain the above copyright
10  *    notice, this list of conditions and the following disclaimer.
11  * 2. Redistributions in binary form must reproduce the above copyright
12  *    notice, this list of conditions and the following disclaimer in the
13  *    documentation and/or other materials provided with the distribution.
14  *
15  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
16  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
17  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
18  * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
19  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
20  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
21  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
22  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
23  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
24  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
25  * SUCH DAMAGE.
26  */
27 
28 #include <sys/param.h>
29 #include <sys/bus.h>
30 #include <sys/kernel.h>
31 #include <sys/module.h>
32 #include <sys/mutex.h>
33 #include <sys/rman.h>
34 #include <machine/bus.h>
35 
36 #include <dev/ofw/ofw_bus.h>
37 #include <dev/ofw/ofw_bus_subr.h>
38 
39 #include <dev/iicbus/iiconf.h>
40 #include <dev/iicbus/iicbus.h>
41 
42 #include <dev/clk/clk.h>
43 
44 #include "iicbus_if.h"
45 
46 #define	RK_I2C_CON			0x00
47 #define	 RK_I2C_CON_EN			(1 << 0)
48 #define	 RK_I2C_CON_MODE_SHIFT		1
49 #define	 RK_I2C_CON_MODE_TX		0
50 #define	 RK_I2C_CON_MODE_RRX		1
51 #define	 RK_I2C_CON_MODE_RX		2
52 #define	 RK_I2C_CON_MODE_RTX		3
53 #define	 RK_I2C_CON_MODE_MASK		0x6
54 #define	 RK_I2C_CON_START		(1 << 3)
55 #define	 RK_I2C_CON_STOP		(1 << 4)
56 #define	 RK_I2C_CON_LASTACK		(1 << 5)
57 #define	 RK_I2C_CON_NAKSTOP		(1 << 6)
58 #define	 RK_I2C_CON_CTRL_MASK		0xFF
59 
60 #define	RK_I2C_CLKDIV		0x04
61 #define	 RK_I2C_CLKDIVL_MASK	0xFFFF
62 #define	 RK_I2C_CLKDIVL_SHIFT	0
63 #define	 RK_I2C_CLKDIVH_MASK	0xFFFF0000
64 #define	 RK_I2C_CLKDIVH_SHIFT	16
65 #define	 RK_I2C_CLKDIV_MUL	8
66 
67 #define	RK_I2C_MRXADDR			0x08
68 #define	 RK_I2C_MRXADDR_SADDR_MASK	0xFFFFFF
69 #define	 RK_I2C_MRXADDR_VALID(x)	(1 << (24 + x))
70 
71 #define	RK_I2C_MRXRADDR			0x0C
72 #define	 RK_I2C_MRXRADDR_SRADDR_MASK	0xFFFFFF
73 #define	 RK_I2C_MRXRADDR_VALID(x)	(1 << (24 + x))
74 
75 #define	RK_I2C_MTXCNT		0x10
76 #define	 RK_I2C_MTXCNT_MASK	0x3F
77 
78 #define	RK_I2C_MRXCNT		0x14
79 #define	 RK_I2C_MRXCNT_MASK	0x3F
80 
81 #define	RK_I2C_IEN		0x18
82 #define	 RK_I2C_IEN_BTFIEN	(1 << 0)
83 #define	 RK_I2C_IEN_BRFIEN	(1 << 1)
84 #define	 RK_I2C_IEN_MBTFIEN	(1 << 2)
85 #define	 RK_I2C_IEN_MBRFIEN	(1 << 3)
86 #define	 RK_I2C_IEN_STARTIEN	(1 << 4)
87 #define	 RK_I2C_IEN_STOPIEN	(1 << 5)
88 #define	 RK_I2C_IEN_NAKRCVIEN	(1 << 6)
89 #define	 RK_I2C_IEN_ALL		(RK_I2C_IEN_MBTFIEN | RK_I2C_IEN_MBRFIEN | \
90 	RK_I2C_IEN_STARTIEN | RK_I2C_IEN_STOPIEN | RK_I2C_IEN_NAKRCVIEN)
91 
92 #define	RK_I2C_IPD		0x1C
93 #define	 RK_I2C_IPD_BTFIPD	(1 << 0)
94 #define	 RK_I2C_IPD_BRFIPD	(1 << 1)
95 #define	 RK_I2C_IPD_MBTFIPD	(1 << 2)
96 #define	 RK_I2C_IPD_MBRFIPD	(1 << 3)
97 #define	 RK_I2C_IPD_STARTIPD	(1 << 4)
98 #define	 RK_I2C_IPD_STOPIPD	(1 << 5)
99 #define	 RK_I2C_IPD_NAKRCVIPD	(1 << 6)
100 #define	 RK_I2C_IPD_ALL		(RK_I2C_IPD_MBTFIPD | RK_I2C_IPD_MBRFIPD | \
101 	RK_I2C_IPD_STARTIPD | RK_I2C_IPD_STOPIPD | RK_I2C_IPD_NAKRCVIPD)
102 
103 #define	RK_I2C_FNCT		0x20
104 #define	 RK_I2C_FNCT_MASK	0x3F
105 
106 #define	RK_I2C_TXDATA_BASE	0x100
107 
108 #define	RK_I2C_RXDATA_BASE	0x200
109 
110 /* 8 data registers, 4 bytes each. */
111 #define	RK_I2C_MAX_RXTX_LEN	32
112 
113 enum rk_i2c_state {
114 	STATE_IDLE = 0,
115 	STATE_START,
116 	STATE_READ,
117 	STATE_WRITE,
118 	STATE_STOP
119 };
120 
121 struct rk_i2c_softc {
122 	device_t	dev;
123 	struct resource	*res[2];
124 	struct mtx	mtx;
125 	clk_t		sclk;
126 	clk_t		pclk;
127 	int		busy;
128 	void *		intrhand;
129 	uint32_t	intr;
130 	uint32_t	ipd;
131 	struct iic_msg	*msg;
132 	size_t		cnt;
133 	bool		transfer_done;
134 	bool		nak_recv;
135 	bool		tx_slave_addr;
136 	uint8_t		mode;
137 	uint8_t		state;
138 
139 	device_t	iicbus;
140 };
141 
142 static struct ofw_compat_data compat_data[] = {
143 	{"rockchip,rk3288-i2c", 1},
144 	{"rockchip,rk3328-i2c", 1},
145 	{"rockchip,rk3399-i2c", 1},
146 	{NULL,             0}
147 };
148 
149 static struct resource_spec rk_i2c_spec[] = {
150 	{ SYS_RES_MEMORY,	0,	RF_ACTIVE },
151 	{ SYS_RES_IRQ,		0,	RF_ACTIVE | RF_SHAREABLE },
152 	{ -1, 0 }
153 };
154 
155 static int rk_i2c_probe(device_t dev);
156 static int rk_i2c_attach(device_t dev);
157 static int rk_i2c_detach(device_t dev);
158 
159 #define	RK_I2C_LOCK(sc)			mtx_lock(&(sc)->mtx)
160 #define	RK_I2C_UNLOCK(sc)		mtx_unlock(&(sc)->mtx)
161 #define	RK_I2C_ASSERT_LOCKED(sc)	mtx_assert(&(sc)->mtx, MA_OWNED)
162 #define	RK_I2C_READ(sc, reg)		bus_read_4((sc)->res[0], (reg))
163 #define	RK_I2C_WRITE(sc, reg, val)	bus_write_4((sc)->res[0], (reg), (val))
164 
165 static uint32_t
166 rk_i2c_get_clkdiv(struct rk_i2c_softc *sc, uint32_t speed)
167 {
168 	uint64_t sclk_freq;
169 	uint32_t clkdiv;
170 	int err;
171 
172 	err = clk_get_freq(sc->sclk, &sclk_freq);
173 	if (err != 0)
174 		return (err);
175 
176 	clkdiv = (sclk_freq / speed / RK_I2C_CLKDIV_MUL / 2) - 1;
177 	clkdiv &= RK_I2C_CLKDIVL_MASK;
178 
179 	clkdiv = clkdiv << RK_I2C_CLKDIVH_SHIFT | clkdiv;
180 
181 	return (clkdiv);
182 }
183 
184 static int
185 rk_i2c_reset(device_t dev, u_char speed, u_char addr, u_char *oldaddr)
186 {
187 	struct rk_i2c_softc *sc;
188 	uint32_t clkdiv;
189 	u_int busfreq;
190 
191 	sc = device_get_softc(dev);
192 
193 	busfreq = IICBUS_GET_FREQUENCY(sc->iicbus, speed);
194 
195 	clkdiv = rk_i2c_get_clkdiv(sc, busfreq);
196 
197 	RK_I2C_LOCK(sc);
198 
199 	/* Set the clock divider */
200 	RK_I2C_WRITE(sc, RK_I2C_CLKDIV, clkdiv);
201 
202 	/* Disable the module */
203 	RK_I2C_WRITE(sc, RK_I2C_CON, 0);
204 
205 	RK_I2C_UNLOCK(sc);
206 
207 	return (0);
208 }
209 
210 static uint8_t
211 rk_i2c_fill_tx(struct rk_i2c_softc *sc)
212 {
213 	uint32_t buf32;
214 	uint8_t buf;
215 	int i, j, len;
216 
217 	len = sc->msg->len - sc->cnt;
218 	if (sc->tx_slave_addr) {
219 		KASSERT(sc->cnt == 0, ("tx_slave_addr in the middle of data"));
220 		len++;
221 	}
222 
223 	if (len > RK_I2C_MAX_RXTX_LEN)
224 		len = RK_I2C_MAX_RXTX_LEN;
225 
226 	for (i = 0; i < len; ) {
227 		buf32 = 0;
228 
229 		/* Process next 4 bytes or whatever remains. */
230 		for (j = 0; j < MIN(len - i, 4); j++) {
231 			/* Fill the addr if needed */
232 			if (sc->tx_slave_addr) {
233 				buf = sc->msg->slave;
234 				sc->tx_slave_addr = false;
235 			} else {
236 				KASSERT(sc->cnt < sc->msg->len,
237 				    ("%s: data buffer overrun", __func__));
238 				buf = sc->msg->buf[sc->cnt];
239 				sc->cnt++;
240 			}
241 			buf32 |= (uint32_t)buf << (j * 8);
242 		}
243 
244 		KASSERT(i % 4 == 0, ("%s: misaligned write offset", __func__));
245 		RK_I2C_WRITE(sc, RK_I2C_TXDATA_BASE + i, buf32);
246 
247 		i += j;
248 	}
249 
250 	return (len);
251 }
252 
253 static void
254 rk_i2c_drain_rx(struct rk_i2c_softc *sc)
255 {
256 	uint32_t buf32 = 0;
257 	uint8_t buf8;
258 	int len;
259 	int i;
260 
261 	if (sc->msg == NULL) {
262 		device_printf(sc->dev, "No current iic msg\n");
263 		return;
264 	}
265 
266 	len = sc->msg->len - sc->cnt;
267 	if (len > RK_I2C_MAX_RXTX_LEN)
268 		len = RK_I2C_MAX_RXTX_LEN;
269 
270 	for (i = 0; i < len; i++) {
271 		if (i % 4 == 0)
272 			buf32 = RK_I2C_READ(sc, RK_I2C_RXDATA_BASE + i);
273 
274 		buf8 = (buf32 >> ((i % 4) * 8)) & 0xFF;
275 		sc->msg->buf[sc->cnt++] = buf8;
276 	}
277 }
278 
279 static void
280 rk_i2c_send_stop(struct rk_i2c_softc *sc)
281 {
282 	uint32_t reg;
283 
284 	if (!(sc->msg->flags & IIC_M_NOSTOP)) {
285 		RK_I2C_WRITE(sc, RK_I2C_IEN, RK_I2C_IEN_STOPIEN);
286 
287 		sc->state = STATE_STOP;
288 
289 		reg = RK_I2C_READ(sc, RK_I2C_CON);
290 		reg |= RK_I2C_CON_STOP;
291 		RK_I2C_WRITE(sc, RK_I2C_CON, reg);
292 	} else {
293 		/*
294 		 * Do not actually set stop bit, set up conditions to
295 		 * emulate repeated start by clearing all state.
296 		 */
297 		sc->state = STATE_IDLE;
298 		sc->transfer_done = 1;
299 
300 		reg = RK_I2C_READ(sc, RK_I2C_CON);
301 		reg &= ~RK_I2C_CON_CTRL_MASK;
302 		RK_I2C_WRITE(sc, RK_I2C_CON, reg);
303 	}
304 }
305 
306 static void
307 rk_i2c_intr_locked(struct rk_i2c_softc *sc)
308 {
309 	uint32_t reg;
310 	int transfer_len;
311 
312 	sc->ipd = RK_I2C_READ(sc, RK_I2C_IPD);
313 
314 	/* Something to handle? */
315 	if ((sc->ipd & RK_I2C_IPD_ALL) == 0)
316 		return;
317 
318 	RK_I2C_WRITE(sc, RK_I2C_IPD, sc->ipd);
319 	sc->ipd &= RK_I2C_IPD_ALL;
320 
321 	if (sc->ipd & RK_I2C_IPD_NAKRCVIPD) {
322 		/* NACK received */
323 		sc->ipd &= ~RK_I2C_IPD_NAKRCVIPD;
324 		sc->nak_recv = true;
325 		/* XXXX last byte !!!, signal error !!! */
326 		sc->transfer_done = true;
327 		sc->state = STATE_IDLE;
328 		goto err;
329 	}
330 
331 	switch (sc->state) {
332 	case STATE_START:
333 		/* Disable start bit */
334 		reg = RK_I2C_READ(sc, RK_I2C_CON);
335 		reg &= ~RK_I2C_CON_START;
336 		RK_I2C_WRITE(sc, RK_I2C_CON, reg);
337 
338 		if (sc->mode == RK_I2C_CON_MODE_RRX ||
339 		    sc->mode == RK_I2C_CON_MODE_RX) {
340 			sc->state = STATE_READ;
341 			RK_I2C_WRITE(sc, RK_I2C_IEN, RK_I2C_IEN_MBRFIEN |
342 			    RK_I2C_IEN_NAKRCVIEN);
343 
344 			if ((sc->msg->len - sc->cnt) > 32)
345 				transfer_len = 32;
346 			else {
347 				transfer_len = sc->msg->len - sc->cnt;
348 				reg = RK_I2C_READ(sc, RK_I2C_CON);
349 				reg |= RK_I2C_CON_LASTACK;
350 				RK_I2C_WRITE(sc, RK_I2C_CON, reg);
351 			}
352 
353 			RK_I2C_WRITE(sc, RK_I2C_MRXCNT, transfer_len);
354 		} else {
355 			sc->state = STATE_WRITE;
356 			RK_I2C_WRITE(sc, RK_I2C_IEN, RK_I2C_IEN_MBTFIEN |
357 			    RK_I2C_IEN_NAKRCVIEN);
358 
359 			transfer_len = rk_i2c_fill_tx(sc);
360 			RK_I2C_WRITE(sc, RK_I2C_MTXCNT, transfer_len);
361 		}
362 		break;
363 	case STATE_READ:
364 		rk_i2c_drain_rx(sc);
365 
366 		if (sc->cnt == sc->msg->len) {
367 			rk_i2c_send_stop(sc);
368 		} else {
369 			sc->mode = RK_I2C_CON_MODE_RX;
370 			reg = RK_I2C_READ(sc, RK_I2C_CON) & \
371 			    ~RK_I2C_CON_CTRL_MASK;
372 			reg |= sc->mode << RK_I2C_CON_MODE_SHIFT;
373 			reg |= RK_I2C_CON_EN;
374 
375 			if ((sc->msg->len - sc->cnt) > 32)
376 				transfer_len = 32;
377 			else {
378 				transfer_len = sc->msg->len - sc->cnt;
379 				reg |= RK_I2C_CON_LASTACK;
380 			}
381 
382 			RK_I2C_WRITE(sc, RK_I2C_CON, reg);
383 			RK_I2C_WRITE(sc, RK_I2C_MRXCNT, transfer_len);
384 		}
385 		break;
386 	case STATE_WRITE:
387 		if (sc->cnt < sc->msg->len) {
388 			/* Keep writing. */
389 			RK_I2C_WRITE(sc, RK_I2C_IEN, RK_I2C_IEN_MBTFIEN |
390 			    RK_I2C_IEN_NAKRCVIEN);
391 			transfer_len = rk_i2c_fill_tx(sc);
392 			RK_I2C_WRITE(sc, RK_I2C_MTXCNT, transfer_len);
393 		} else {
394 			rk_i2c_send_stop(sc);
395 		}
396 		break;
397 	case STATE_STOP:
398 		/* Disable stop bit */
399 		reg = RK_I2C_READ(sc, RK_I2C_CON);
400 		reg &= ~RK_I2C_CON_STOP;
401 		RK_I2C_WRITE(sc, RK_I2C_CON, reg);
402 
403 		sc->transfer_done = 1;
404 		sc->state = STATE_IDLE;
405 		break;
406 	case STATE_IDLE:
407 		break;
408 	}
409 
410 err:
411 	wakeup(sc);
412 }
413 
414 static void
415 rk_i2c_intr(void *arg)
416 {
417 	struct rk_i2c_softc *sc;
418 
419 	sc = (struct rk_i2c_softc *)arg;
420 
421 	RK_I2C_LOCK(sc);
422 	rk_i2c_intr_locked(sc);
423 	RK_I2C_UNLOCK(sc);
424 }
425 
426 static void
427 rk_i2c_start_xfer(struct rk_i2c_softc *sc, struct iic_msg *msg, boolean_t last)
428 {
429 	uint32_t reg;
430 	uint8_t len;
431 
432 	sc->transfer_done = false;
433 	sc->nak_recv = false;
434 	sc->tx_slave_addr = false;
435 	sc->cnt = 0;
436 	sc->state = STATE_IDLE;
437 	sc->msg = msg;
438 
439 	reg = RK_I2C_READ(sc, RK_I2C_CON) & ~RK_I2C_CON_CTRL_MASK;
440 	if (!(sc->msg->flags & IIC_M_NOSTART)) {
441 		/* Stadard message */
442 		if (sc->mode == RK_I2C_CON_MODE_TX) {
443 			sc->tx_slave_addr = true;
444 		}
445 		sc->state = STATE_START;
446 		reg |= RK_I2C_CON_START;
447 
448 		RK_I2C_WRITE(sc, RK_I2C_IEN, RK_I2C_IEN_STARTIEN);
449 	} else {
450 		/* Continuation message */
451 		if (sc->mode == RK_I2C_CON_MODE_RX) {
452 			sc->state = STATE_READ;
453 			if (last)
454 				reg |= RK_I2C_CON_LASTACK;
455 
456 			RK_I2C_WRITE(sc, RK_I2C_MRXCNT, sc->msg->len);
457 			RK_I2C_WRITE(sc, RK_I2C_IEN, RK_I2C_IEN_MBRFIEN |
458 			    RK_I2C_IEN_NAKRCVIEN);
459 		} else {
460 			sc->state = STATE_WRITE;
461 			len = rk_i2c_fill_tx(sc);
462 
463 			RK_I2C_WRITE(sc, RK_I2C_MTXCNT, len);
464 
465 			RK_I2C_WRITE(sc, RK_I2C_IEN, RK_I2C_IEN_MBTFIEN |
466 			    RK_I2C_IEN_NAKRCVIEN);
467 		}
468 	}
469 	reg |= RK_I2C_CON_NAKSTOP;
470 	reg |= sc->mode << RK_I2C_CON_MODE_SHIFT;
471 	reg |= RK_I2C_CON_EN;
472 	RK_I2C_WRITE(sc, RK_I2C_CON, reg);
473 }
474 
475 static int
476 rk_i2c_transfer(device_t dev, struct iic_msg *msgs, uint32_t nmsgs)
477 {
478 	struct rk_i2c_softc *sc;
479 	uint32_t reg;
480 	bool last_msg;
481 	int i, j, timeout, err;
482 
483 	sc = device_get_softc(dev);
484 
485 	RK_I2C_LOCK(sc);
486 
487 	while (sc->busy)
488 		mtx_sleep(sc, &sc->mtx, 0, "i2cbuswait", 0);
489 	sc->busy = 1;
490 
491 	/* Disable the module and interrupts */
492 	RK_I2C_WRITE(sc, RK_I2C_CON, 0);
493 	RK_I2C_WRITE(sc, RK_I2C_IEN, 0);
494 
495 	/* Clean stale interrupts */
496 	RK_I2C_WRITE(sc, RK_I2C_IPD, RK_I2C_IPD_ALL);
497 
498 	err = 0;
499 	for (i = 0; i < nmsgs; i++) {
500 		/* Validate parameters. */
501 		if (msgs == NULL || msgs[i].buf == NULL ||
502 		    msgs[i].len == 0) {
503 			err = IIC_ENOTSUPP;
504 			break;
505 		}
506 		/*
507 		 * If next message have NOSTART flag, then they both
508 		 * should be same type (read/write) and same address.
509 		 */
510 		if (i < nmsgs - 1) {
511 			if ((msgs[i + 1].flags & IIC_M_NOSTART) &&
512 			    ((msgs[i].flags & IIC_M_RD) !=
513 			    (msgs[i + 1].flags & IIC_M_RD) ||
514 			    (msgs[i].slave !=  msgs[i + 1].slave))) {
515 				err = IIC_ENOTSUPP;
516 				break;
517 			}
518 		}
519 		/*
520 		 * Detect simple register read case.
521 		 * The first message should be IIC_M_WR | IIC_M_NOSTOP,
522 		 * next pure IIC_M_RD (no other flags allowed). Both
523 		 * messages should have same slave address.
524 		 */
525 
526 		if (nmsgs - i >= 2 && msgs[i].len < 4 &&
527 		    msgs[i].flags == (IIC_M_WR  | IIC_M_NOSTOP) &&
528 		    (msgs[i + 1].flags & IIC_M_RD) == IIC_M_RD &&
529 		    (msgs[i].slave & ~LSB) == (msgs[i + 1].slave & ~LSB)) {
530 			sc->mode = RK_I2C_CON_MODE_RRX;
531 
532 			/* Write slave address */
533 			reg = msgs[i].slave & ~LSB;
534 			reg |= RK_I2C_MRXADDR_VALID(0);
535 			RK_I2C_WRITE(sc, RK_I2C_MRXADDR, reg);
536 
537 			/* Write slave register address */
538 			reg = 0;
539 			for (j = 0; j < msgs[i].len ; j++) {
540 				reg |= (uint32_t)msgs[i].buf[j] << (j * 8);
541 				reg |= RK_I2C_MRXADDR_VALID(j);
542 			}
543 			RK_I2C_WRITE(sc, RK_I2C_MRXRADDR, reg);
544 
545 			i++;
546 		} else {
547 			if (msgs[i].flags & IIC_M_RD) {
548 				if (msgs[i].flags & IIC_M_NOSTART) {
549 					sc->mode = RK_I2C_CON_MODE_RX;
550 				} else {
551 					sc->mode = RK_I2C_CON_MODE_RRX;
552 					reg = msgs[i].slave & ~LSB;
553 					reg |= RK_I2C_MRXADDR_VALID(0);
554 					RK_I2C_WRITE(sc, RK_I2C_MRXADDR, reg);
555 					RK_I2C_WRITE(sc, RK_I2C_MRXRADDR, 0);
556 				}
557 			} else {
558 				sc->mode = RK_I2C_CON_MODE_TX;
559 			}
560 		}
561 		/* last message ? */
562 		last_msg = (i >= nmsgs - 1) ||
563 		    !(msgs[i + 1].flags & IIC_M_NOSTART);
564 		rk_i2c_start_xfer(sc, msgs + i, last_msg);
565 
566 		if (cold) {
567 			for(timeout = 10000; timeout > 0; timeout--)  {
568 				rk_i2c_intr_locked(sc);
569 				if (sc->transfer_done)
570 					break;
571 				DELAY(1000);
572 			}
573 			if (timeout <= 0)
574 				err = IIC_ETIMEOUT;
575 		} else {
576 			while (err == 0 && !sc->transfer_done) {
577 				err = msleep(sc, &sc->mtx, PZERO, "rk_i2c",
578 				    10 * hz);
579 			}
580 		}
581 	}
582 
583 	/* Disable the module and interrupts */
584 	RK_I2C_WRITE(sc, RK_I2C_CON, 0);
585 	RK_I2C_WRITE(sc, RK_I2C_IEN, 0);
586 
587 	sc->busy = 0;
588 
589 	if (sc->nak_recv)
590 		err = IIC_ENOACK;
591 
592 	RK_I2C_UNLOCK(sc);
593 	return (err);
594 }
595 
596 static int
597 rk_i2c_probe(device_t dev)
598 {
599 
600 	if (!ofw_bus_status_okay(dev))
601 		return (ENXIO);
602 	if (ofw_bus_search_compatible(dev, compat_data)->ocd_data == 0)
603 		return (ENXIO);
604 
605 	device_set_desc(dev, "RockChip I2C");
606 	return (BUS_PROBE_DEFAULT);
607 }
608 
609 static int
610 rk_i2c_attach(device_t dev)
611 {
612 	struct rk_i2c_softc *sc;
613 	int error;
614 
615 	sc = device_get_softc(dev);
616 	sc->dev = dev;
617 
618 	mtx_init(&sc->mtx, device_get_nameunit(dev), "rk_i2c", MTX_DEF);
619 
620 	if (bus_alloc_resources(dev, rk_i2c_spec, sc->res) != 0) {
621 		device_printf(dev, "cannot allocate resources for device\n");
622 		error = ENXIO;
623 		goto fail;
624 	}
625 
626 	if (bus_setup_intr(dev, sc->res[1],
627 	    INTR_TYPE_MISC | INTR_MPSAFE, NULL, rk_i2c_intr, sc,
628 	    &sc->intrhand)) {
629 		bus_release_resources(dev, rk_i2c_spec, sc->res);
630 		device_printf(dev, "cannot setup interrupt handler\n");
631 		return (ENXIO);
632 	}
633 
634 	clk_set_assigned(dev, ofw_bus_get_node(dev));
635 
636 	/* Activate the module clocks. */
637 	error = clk_get_by_ofw_name(dev, 0, "i2c", &sc->sclk);
638 	if (error != 0) {
639 		device_printf(dev, "cannot get i2c clock\n");
640 		goto fail;
641 	}
642 	error = clk_enable(sc->sclk);
643 	if (error != 0) {
644 		device_printf(dev, "cannot enable i2c clock\n");
645 		goto fail;
646 	}
647 	/* pclk clock is optional. */
648 	error = clk_get_by_ofw_name(dev, 0, "pclk", &sc->pclk);
649 	if (error != 0 && error != ENOENT) {
650 		device_printf(dev, "cannot get pclk clock\n");
651 		goto fail;
652 	}
653 	if (sc->pclk != NULL) {
654 		error = clk_enable(sc->pclk);
655 		if (error != 0) {
656 			device_printf(dev, "cannot enable pclk clock\n");
657 			goto fail;
658 		}
659 	}
660 
661 	sc->iicbus = device_add_child(dev, "iicbus", DEVICE_UNIT_ANY);
662 	if (sc->iicbus == NULL) {
663 		device_printf(dev, "cannot add iicbus child device\n");
664 		error = ENXIO;
665 		goto fail;
666 	}
667 
668 	bus_attach_children(dev);
669 
670 	return (0);
671 
672 fail:
673 	if (rk_i2c_detach(dev) != 0)
674 		device_printf(dev, "Failed to detach\n");
675 	return (error);
676 }
677 
678 static int
679 rk_i2c_detach(device_t dev)
680 {
681 	struct rk_i2c_softc *sc;
682 	int error;
683 
684 	sc = device_get_softc(dev);
685 
686 	if ((error = bus_generic_detach(dev)) != 0)
687 		return (error);
688 
689 	if (sc->iicbus != NULL)
690 		if ((error = device_delete_child(dev, sc->iicbus)) != 0)
691 			return (error);
692 
693 	if (sc->sclk != NULL)
694 		clk_release(sc->sclk);
695 	if (sc->pclk != NULL)
696 		clk_release(sc->pclk);
697 
698 	if (sc->intrhand != NULL)
699 		bus_teardown_intr(sc->dev, sc->res[1], sc->intrhand);
700 
701 	bus_release_resources(dev, rk_i2c_spec, sc->res);
702 
703 	mtx_destroy(&sc->mtx);
704 
705 	return (0);
706 }
707 
708 static phandle_t
709 rk_i2c_get_node(device_t bus, device_t dev)
710 {
711 
712 	return ofw_bus_get_node(bus);
713 }
714 
715 static device_method_t rk_i2c_methods[] = {
716 	DEVMETHOD(device_probe,		rk_i2c_probe),
717 	DEVMETHOD(device_attach,	rk_i2c_attach),
718 	DEVMETHOD(device_detach,	rk_i2c_detach),
719 
720 	/* OFW methods */
721 	DEVMETHOD(ofw_bus_get_node,		rk_i2c_get_node),
722 
723 	DEVMETHOD(iicbus_callback,	iicbus_null_callback),
724 	DEVMETHOD(iicbus_reset,		rk_i2c_reset),
725 	DEVMETHOD(iicbus_transfer,	rk_i2c_transfer),
726 
727 	DEVMETHOD_END
728 };
729 
730 static driver_t rk_i2c_driver = {
731 	"rk_i2c",
732 	rk_i2c_methods,
733 	sizeof(struct rk_i2c_softc),
734 };
735 
736 EARLY_DRIVER_MODULE(rk_i2c, simplebus, rk_i2c_driver, 0, 0,
737     BUS_PASS_INTERRUPT + BUS_PASS_ORDER_LATE);
738 EARLY_DRIVER_MODULE(ofw_iicbus, rk_i2c, ofw_iicbus_driver,
739     0, 0, BUS_PASS_INTERRUPT + BUS_PASS_ORDER_LATE);
740 MODULE_DEPEND(rk_i2c, iicbus, 1, 1, 1);
741 MODULE_VERSION(rk_i2c, 1);
742