1/*-
2 * Copyright (c) 2001 Tsubai Masanari.  All rights reserved.
3 *
4 * Redistribution and use in source and binary forms, with or without
5 * modification, are permitted provided that the following conditions
6 * are met:
7 * 1. Redistributions of source code must retain the above copyright
8 *    notice, this list of conditions and the following disclaimer.
9 * 2. Redistributions in binary form must reproduce the above copyright
10 *    notice, this list of conditions and the following disclaimer in the
11 *    documentation and/or other materials provided with the distribution.
12 * 3. The name of the author may not be used to endorse or promote products
13 *    derived from this software without specific prior written permission.
14 *
15 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
16 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
17 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
18 * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
19 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
20 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
21 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
22 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
23 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
24 * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
25 *
26 * $FreeBSD$
27 *	NetBSD: ki2c.c,v 1.11 2007/12/06 17:00:33 ad Exp
28 *	Id: ki2c.c,v 1.7 2002/10/05 09:56:05 tsubai Exp
29 */
30
31/*
32 * 	Support routines for the Keywest I2C controller.
33 */
34
35#include <sys/param.h>
36#include <sys/systm.h>
37#include <sys/kernel.h>
38#include <sys/module.h>
39#include <sys/bus.h>
40#include <sys/lock.h>
41#include <sys/mutex.h>
42#include <machine/resource.h>
43#include <machine/bus.h>
44#include <sys/rman.h>
45
46#include <dev/iicbus/iicbus.h>
47#include <dev/iicbus/iiconf.h>
48#include <dev/ofw/ofw_bus.h>
49#include "iicbus_if.h"
50
51/* Keywest I2C Register offsets */
52#define MODE	0
53#define CONTROL	1
54#define STATUS	2
55#define ISR	3
56#define IER	4
57#define ADDR	5
58#define SUBADDR	6
59#define DATA	7
60#define REV	8
61
62/* MODE */
63#define I2C_SPEED	0x03	/* Speed mask */
64#define  I2C_100kHz	0x00
65#define  I2C_50kHz	0x01
66#define  I2C_25kHz	0x02
67#define I2C_MODE	0x0c	/* Mode mask */
68#define  I2C_DUMBMODE	0x00	/*  Dumb mode */
69#define  I2C_STDMODE	0x04	/*  Standard mode */
70#define  I2C_STDSUBMODE	0x08	/*  Standard mode + sub address */
71#define  I2C_COMBMODE	0x0c	/*  Combined mode */
72#define I2C_PORT	0xf0	/* Port mask */
73
74/* CONTROL */
75#define I2C_CT_AAK	0x01	/* Send AAK */
76#define I2C_CT_ADDR	0x02	/* Send address(es) */
77#define I2C_CT_STOP	0x04	/* Send STOP */
78#define I2C_CT_START	0x08	/* Send START */
79
80/* STATUS */
81#define I2C_ST_BUSY	0x01	/* Busy */
82#define I2C_ST_LASTAAK	0x02	/* Last AAK */
83#define I2C_ST_LASTRW	0x04	/* Last R/W */
84#define I2C_ST_SDA	0x08	/* SDA */
85#define I2C_ST_SCL	0x10	/* SCL */
86
87/* ISR/IER */
88#define I2C_INT_DATA	0x01	/* Data byte sent/received */
89#define I2C_INT_ADDR	0x02	/* Address sent */
90#define I2C_INT_STOP	0x04	/* STOP condition sent */
91#define I2C_INT_START	0x08	/* START condition sent */
92
93/* I2C flags */
94#define I2C_BUSY	0x01
95#define I2C_READING	0x02
96#define I2C_ERROR	0x04
97#define I2C_SELECTED	0x08
98
99struct kiic_softc {
100	device_t 		 sc_dev;
101	phandle_t		 sc_node;
102	struct mtx 		 sc_mutex;
103	struct resource		*sc_reg;
104	int			 sc_irqrid;
105	struct resource		*sc_irq;
106	void			*sc_ih;
107	u_int 			 sc_regstep;
108	u_int 			 sc_flags;
109	u_char			*sc_data;
110	int 			 sc_resid;
111	uint16_t		 sc_i2c_base;
112	device_t 		 sc_iicbus;
113};
114
115static int 	kiic_probe(device_t dev);
116static int 	kiic_attach(device_t dev);
117static void 	kiic_writereg(struct kiic_softc *sc, u_int, u_int);
118static u_int 	kiic_readreg(struct kiic_softc *, u_int);
119static void 	kiic_setport(struct kiic_softc *, u_int);
120static void 	kiic_setmode(struct kiic_softc *, u_int);
121static void 	kiic_setspeed(struct kiic_softc *, u_int);
122static void 	kiic_intr(void *xsc);
123static int	kiic_transfer(device_t dev, struct iic_msg *msgs,
124		    uint32_t nmsgs);
125static phandle_t kiic_get_node(device_t bus, device_t dev);
126
127static device_method_t kiic_methods[] = {
128	/* device interface */
129	DEVMETHOD(device_probe, 	kiic_probe),
130	DEVMETHOD(device_attach, 	kiic_attach),
131
132	/* iicbus interface */
133	DEVMETHOD(iicbus_callback,	iicbus_null_callback),
134	DEVMETHOD(iicbus_transfer,	kiic_transfer),
135
136	/* ofw_bus interface */
137	DEVMETHOD(ofw_bus_get_node,	kiic_get_node),
138
139	{ 0, 0 }
140};
141
142static driver_t kiic_driver = {
143	"iichb",
144	kiic_methods,
145	sizeof(struct kiic_softc)
146};
147static devclass_t kiic_devclass;
148
149DRIVER_MODULE(kiic, macio, kiic_driver, kiic_devclass, 0, 0);
150DRIVER_MODULE(kiic, unin, kiic_driver, kiic_devclass, 0, 0);
151
152static int
153kiic_probe(device_t self)
154{
155	const char *name;
156
157	name = ofw_bus_get_name(self);
158	if (name && strcmp(name, "i2c") == 0) {
159		device_set_desc(self, "Keywest I2C controller");
160		return (0);
161	}
162
163	return (ENXIO);
164}
165
166static int
167kiic_attach(device_t self)
168{
169	struct kiic_softc *sc = device_get_softc(self);
170	int rid, rate;
171	phandle_t node;
172	char name[64];
173
174	bzero(sc, sizeof(*sc));
175	sc->sc_dev = self;
176
177	node = ofw_bus_get_node(self);
178	if (node == 0 || node == -1) {
179		return (EINVAL);
180	}
181
182	rid = 0;
183	sc->sc_reg = bus_alloc_resource_any(self, SYS_RES_MEMORY,
184			&rid, RF_ACTIVE);
185	if (sc->sc_reg == NULL) {
186		return (ENOMEM);
187	}
188
189	if (OF_getencprop(node, "AAPL,i2c-rate", &rate, 4) != 4) {
190		device_printf(self, "cannot get i2c-rate\n");
191		return (ENXIO);
192	}
193	if (OF_getencprop(node, "AAPL,address-step", &sc->sc_regstep, 4) != 4) {
194		device_printf(self, "unable to find i2c address step\n");
195		return (ENXIO);
196	}
197
198	/*
199	 * Some Keywest I2C devices have their children attached directly
200	 * underneath them.  Some have a single 'iicbus' child with the
201	 * devices underneath that.  Sort this out, and make sure that the
202	 * OFW I2C layer has the correct node.
203	 *
204	 * Note: the I2C children of the Uninorth bridges have two ports.
205	 *  In general, the port is designated in the 9th bit of the I2C
206	 *  address. However, for kiic devices with children attached below
207	 *  an i2c-bus node, the port is indicated in the 'reg' property
208	 *  of the i2c-bus node.
209	 */
210
211	sc->sc_node = node;
212
213	node = OF_child(node);
214	if (OF_getprop(node, "name", name, sizeof(name)) > 0) {
215		if (strcmp(name,"i2c-bus") == 0) {
216			phandle_t reg;
217			if (OF_getprop(node, "reg", &reg, sizeof(reg)) > 0)
218				sc->sc_i2c_base = reg << 8;
219
220			sc->sc_node = node;
221		}
222	}
223
224	mtx_init(&sc->sc_mutex, "kiic", NULL, MTX_DEF);
225
226	sc->sc_irq = bus_alloc_resource_any(self, SYS_RES_IRQ, &sc->sc_irqrid,
227	    RF_ACTIVE);
228	bus_setup_intr(self, sc->sc_irq, INTR_TYPE_MISC | INTR_MPSAFE, NULL,
229	    kiic_intr, sc, &sc->sc_ih);
230
231	kiic_writereg(sc, ISR, kiic_readreg(sc, ISR));
232	kiic_writereg(sc, STATUS, 0);
233	kiic_writereg(sc, IER, 0);
234
235	kiic_setmode(sc, I2C_STDMODE);
236	kiic_setspeed(sc, I2C_100kHz);		/* XXX rate */
237
238	kiic_writereg(sc, IER, I2C_INT_DATA | I2C_INT_ADDR | I2C_INT_STOP);
239
240	if (bootverbose)
241		device_printf(self, "Revision: %02X\n", kiic_readreg(sc, REV));
242
243	/* Add the IIC bus layer */
244	sc->sc_iicbus = device_add_child(self, "iicbus", -1);
245
246	return (bus_generic_attach(self));
247}
248
249static void
250kiic_writereg(struct kiic_softc *sc, u_int reg, u_int val)
251{
252	bus_write_4(sc->sc_reg, sc->sc_regstep * reg, val);
253	DELAY(100); /* register access delay */
254}
255
256static u_int
257kiic_readreg(struct kiic_softc *sc, u_int reg)
258{
259	return bus_read_4(sc->sc_reg, sc->sc_regstep * reg) & 0xff;
260}
261
262static void
263kiic_setmode(struct kiic_softc *sc, u_int mode)
264{
265	u_int x;
266
267	KASSERT((mode & ~I2C_MODE) == 0, ("bad mode"));
268	x = kiic_readreg(sc, MODE);
269	x &= ~I2C_MODE;
270	x |= mode;
271	kiic_writereg(sc, MODE, x);
272}
273
274static void
275kiic_setport(struct kiic_softc *sc, u_int port)
276{
277	u_int x;
278
279	KASSERT(port == 1 || port == 0, ("bad port"));
280	x = kiic_readreg(sc, MODE);
281	x &= ~I2C_PORT;
282	x |= (port << 4);
283	kiic_writereg(sc, MODE, x);
284}
285
286static void
287kiic_setspeed(struct kiic_softc *sc, u_int speed)
288{
289	u_int x;
290
291	KASSERT((speed & ~I2C_SPEED) == 0, ("bad speed"));
292	x = kiic_readreg(sc, MODE);
293	x &= ~I2C_SPEED;
294	x |= speed;
295	kiic_writereg(sc, MODE, x);
296}
297
298static void
299kiic_intr(void *xsc)
300{
301	struct kiic_softc *sc = xsc;
302	u_int isr;
303	uint32_t x;
304
305	mtx_lock(&sc->sc_mutex);
306	isr = kiic_readreg(sc, ISR);
307
308	if (isr & I2C_INT_ADDR) {
309		sc->sc_flags |= I2C_SELECTED;
310
311		if (sc->sc_flags & I2C_READING) {
312			if (sc->sc_resid > 1) {
313				x = kiic_readreg(sc, CONTROL);
314				x |= I2C_CT_AAK;
315				kiic_writereg(sc, CONTROL, x);
316			}
317		} else {
318			kiic_writereg(sc, DATA, *sc->sc_data++);
319			sc->sc_resid--;
320		}
321	}
322
323	if (isr & I2C_INT_DATA) {
324		if (sc->sc_flags & I2C_READING) {
325			if (sc->sc_resid > 0) {
326				*sc->sc_data++ = kiic_readreg(sc, DATA);
327				sc->sc_resid--;
328			}
329			if (sc->sc_resid == 0)  /* done */
330				kiic_writereg(sc, CONTROL, 0);
331		} else {
332			if (sc->sc_resid == 0) {
333				x = kiic_readreg(sc, CONTROL);
334				x |= I2C_CT_STOP;
335				kiic_writereg(sc, CONTROL, x);
336			} else {
337				kiic_writereg(sc, DATA, *sc->sc_data++);
338				sc->sc_resid--;
339			}
340		}
341	}
342
343	if (isr & I2C_INT_STOP) {
344		kiic_writereg(sc, CONTROL, 0);
345		sc->sc_flags &= ~I2C_SELECTED;
346		wakeup(sc->sc_dev);
347	}
348
349	kiic_writereg(sc, ISR, isr);
350	mtx_unlock(&sc->sc_mutex);
351}
352
353static int
354kiic_transfer(device_t dev, struct iic_msg *msgs, uint32_t nmsgs)
355{
356	struct kiic_softc *sc;
357	int i, x, timo, err;
358	uint16_t addr;
359	uint8_t subaddr;
360
361	sc = device_get_softc(dev);
362	timo = 100;
363	subaddr = 0;
364
365	mtx_lock(&sc->sc_mutex);
366
367	if (sc->sc_flags & I2C_BUSY)
368		mtx_sleep(dev, &sc->sc_mutex, 0, "kiic", timo);
369
370	if (sc->sc_flags & I2C_BUSY) {
371		mtx_unlock(&sc->sc_mutex);
372		return (ETIMEDOUT);
373	}
374
375	sc->sc_flags = I2C_BUSY;
376
377	/* Clear pending interrupts, and reset controller */
378	kiic_writereg(sc, ISR, kiic_readreg(sc, ISR));
379	kiic_writereg(sc, STATUS, 0);
380
381	for (i = 0; i < nmsgs; i++) {
382		if (msgs[i].flags & IIC_M_NOSTOP) {
383			if (msgs[i+1].flags & IIC_M_RD)
384				kiic_setmode(sc, I2C_COMBMODE);
385			else
386				kiic_setmode(sc, I2C_STDSUBMODE);
387			KASSERT(msgs[i].len == 1, ("oversize I2C message"));
388			subaddr = msgs[i].buf[0];
389			i++;
390		} else {
391			kiic_setmode(sc, I2C_STDMODE);
392		}
393
394		sc->sc_data = msgs[i].buf;
395		sc->sc_resid = msgs[i].len;
396		sc->sc_flags = I2C_BUSY;
397		addr = msgs[i].slave;
398		timo = 1000 + sc->sc_resid * 200;
399		timo += 100000;
400
401		if (msgs[i].flags & IIC_M_RD) {
402			sc->sc_flags |= I2C_READING;
403			addr |= 1;
404		}
405
406		addr |= sc->sc_i2c_base;
407
408		kiic_setport(sc, (addr & 0x100) >> 8);
409		kiic_writereg(sc, ADDR, addr & 0xff);
410		kiic_writereg(sc, SUBADDR, subaddr);
411
412		x = kiic_readreg(sc, CONTROL) | I2C_CT_ADDR;
413		kiic_writereg(sc, CONTROL, x);
414
415		err = mtx_sleep(dev, &sc->sc_mutex, 0, "kiic", timo);
416
417		msgs[i].len -= sc->sc_resid;
418
419		if ((sc->sc_flags & I2C_ERROR) || err == EWOULDBLOCK) {
420			device_printf(sc->sc_dev, "I2C error\n");
421			sc->sc_flags = 0;
422			mtx_unlock(&sc->sc_mutex);
423			return (EIO);
424		}
425	}
426
427	sc->sc_flags = 0;
428
429	mtx_unlock(&sc->sc_mutex);
430
431	return (0);
432}
433
434static phandle_t
435kiic_get_node(device_t bus, device_t dev)
436{
437	struct kiic_softc *sc;
438
439	sc = device_get_softc(bus);
440	/* We only have one child, the I2C bus, which needs our own node. */
441
442	return sc->sc_node;
443}
444
445