xref: /freebsd/sys/powerpc/powermac/kiic.c (revision 193d9e768ba63fcfb187cfd17f461f7d41345048)
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 
99 struct 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 
115 static int 	kiic_probe(device_t dev);
116 static int 	kiic_attach(device_t dev);
117 static void 	kiic_writereg(struct kiic_softc *sc, u_int, u_int);
118 static u_int 	kiic_readreg(struct kiic_softc *, u_int);
119 static void 	kiic_setport(struct kiic_softc *, u_int);
120 static void 	kiic_setmode(struct kiic_softc *, u_int);
121 static void 	kiic_setspeed(struct kiic_softc *, u_int);
122 static void 	kiic_intr(void *xsc);
123 static int	kiic_transfer(device_t dev, struct iic_msg *msgs,
124 		    uint32_t nmsgs);
125 static phandle_t kiic_get_node(device_t bus, device_t dev);
126 
127 static 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 
142 static driver_t kiic_driver = {
143 	"iichb",
144 	kiic_methods,
145 	sizeof(struct kiic_softc)
146 };
147 static devclass_t kiic_devclass;
148 
149 DRIVER_MODULE(kiic, macio, kiic_driver, kiic_devclass, 0, 0);
150 DRIVER_MODULE(kiic, unin, kiic_driver, kiic_devclass, 0, 0);
151 
152 static int
153 kiic_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 
166 static int
167 kiic_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 
249 static void
250 kiic_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 
256 static u_int
257 kiic_readreg(struct kiic_softc *sc, u_int reg)
258 {
259 	return bus_read_4(sc->sc_reg, sc->sc_regstep * reg) & 0xff;
260 }
261 
262 static void
263 kiic_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 
274 static void
275 kiic_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 
286 static void
287 kiic_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 
298 static void
299 kiic_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 
353 static int
354 kiic_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 
434 static phandle_t
435 kiic_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