xref: /illumos-gate/usr/src/uts/sun4u/io/i2c/clients/seeprom.c (revision e8ed0869d5c65afe0c37c4755bf81f7381d1f43c)
1 /*
2  * CDDL HEADER START
3  *
4  * The contents of this file are subject to the terms of the
5  * Common Development and Distribution License (the "License").
6  * You may not use this file except in compliance with the License.
7  *
8  * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
9  * or http://www.opensolaris.org/os/licensing.
10  * See the License for the specific language governing permissions
11  * and limitations under the License.
12  *
13  * When distributing Covered Code, include this CDDL HEADER in each
14  * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
15  * If applicable, add the following below this CDDL HEADER, with the
16  * fields enclosed by brackets "[]" replaced with your own identifying
17  * information: Portions Copyright [yyyy] [name of copyright owner]
18  *
19  * CDDL HEADER END
20  */
21 /*
22  * Copyright 2008 Sun Microsystems, Inc.  All rights reserved.
23  * Use is subject to license terms.
24  */
25 
26 
27 #include <sys/stat.h>
28 #include <sys/modctl.h>
29 #include <sys/open.h>
30 #include <sys/types.h>
31 #include <sys/kmem.h>
32 #include <sys/ddi.h>
33 #include <sys/sunddi.h>
34 #include <sys/conf.h>
35 #include <sys/file.h>
36 #include <sys/note.h>
37 #include <sys/i2c/misc/i2c_svc.h>
38 #include <sys/i2c/clients/seeprom_impl.h>
39 
40 /*
41  * cb ops
42  */
43 static int seeprom_open(dev_t *, int, int, cred_t *);
44 static int seeprom_close(dev_t, int, int, cred_t *);
45 static int seeprom_read(dev_t, struct uio *, cred_t *);
46 static int seeprom_write(dev_t, struct uio *, cred_t *);
47 static int seeprom_io(dev_t, struct uio *, int);
48 
49 /*
50  * dev ops
51  */
52 static int seeprom_attach(dev_info_t *dip, ddi_attach_cmd_t cmd);
53 static int seeprom_detach(dev_info_t *dip, ddi_detach_cmd_t cmd);
54 static int seeprom_info(dev_info_t *, ddi_info_cmd_t, void *, void **);
55 
56 static struct cb_ops seeprom_cbops = {
57 	seeprom_open,			/* open */
58 	seeprom_close,			/* close */
59 	nodev,				/* strategy */
60 	nodev,				/* print */
61 	nodev,				/* dump */
62 	seeprom_read,			/* read */
63 	seeprom_write,			/* write */
64 	nodev,				/* ioctl */
65 	nodev,				/* devmap */
66 	nodev,				/* mmap */
67 	nodev,				/* segmap */
68 	nochpoll,			/* poll */
69 	ddi_prop_op,			/* cb_prop_op */
70 	NULL,				/* streamtab */
71 	D_NEW | D_MP | D_HOTPLUG,	/* Driver compatibility flag */
72 	CB_REV,				/* rev */
73 	nodev,				/* int (*cb_aread)() */
74 	nodev				/* int (*cb_awrite)() */
75 };
76 
77 static struct dev_ops seeprom_ops = {
78 	DEVO_REV,
79 	0,
80 	seeprom_info,
81 	nulldev,
82 	nulldev,
83 	seeprom_attach,
84 	seeprom_detach,
85 	nodev,
86 	&seeprom_cbops,
87 	NULL,
88 	nulldev,
89 	ddi_quiesce_not_needed,		/* quiesce */
90 };
91 
92 static struct modldrv seeprom_modldrv = {
93 	&mod_driverops,	 /* type of module - driver */
94 	"I2C serial EEPROM device driver",
95 	&seeprom_ops,
96 };
97 
98 static struct modlinkage seeprom_modlinkage = {
99 	MODREV_1,
100 	&seeprom_modldrv,
101 	0
102 };
103 
104 /*
105  * globals
106  */
107 
108 static void *seepromsoft_statep;
109 
110 int
111 _init(void)
112 {
113 	int error;
114 
115 	if ((error = ddi_soft_state_init(&seepromsoft_statep,
116 	    sizeof (struct seepromunit), 1)) != 0)
117 		return (error);
118 
119 	if ((error = mod_install(&seeprom_modlinkage)) != 0) {
120 		ddi_soft_state_fini(&seepromsoft_statep);
121 		return (error);
122 	}
123 
124 	return (error);
125 }
126 
127 int
128 _fini(void)
129 {
130 	int error;
131 
132 	error = mod_remove(&seeprom_modlinkage);
133 	if (error == 0) {
134 		ddi_soft_state_fini(&seepromsoft_statep);
135 	}
136 
137 	return (error);
138 }
139 
140 int
141 _info(struct modinfo *modinfop)
142 {
143 	return (mod_info(&seeprom_modlinkage, modinfop));
144 }
145 
146 static int
147 seeprom_do_attach(dev_info_t *dip)
148 {
149 	struct seepromunit *unitp;
150 	int instance;
151 	dev_t	dev;
152 
153 	instance = ddi_get_instance(dip);
154 
155 	if (ddi_soft_state_zalloc(seepromsoft_statep, instance) != 0) {
156 		cmn_err(CE_WARN, "%s_%d: failed to zalloc softstate",
157 		    ddi_node_name(dip), instance);
158 
159 		return (DDI_FAILURE);
160 	}
161 
162 	unitp = ddi_get_soft_state(seepromsoft_statep, instance);
163 
164 	unitp->seeprom_dip = dip;
165 
166 	(void) snprintf(unitp->seeprom_name, sizeof (unitp->seeprom_name),
167 	    "%s%d", ddi_driver_name(dip), instance);
168 
169 	if (ddi_create_minor_node(dip, ddi_node_name(dip), S_IFCHR,
170 	    instance, SEEPROM_NODE_TYPE, NULL) == DDI_FAILURE) {
171 		cmn_err(CE_WARN, "%s ddi_create_minor_node failed for '%s'",
172 		    unitp->seeprom_name, ddi_node_name(dip));
173 		ddi_soft_state_free(seepromsoft_statep, instance);
174 
175 		return (DDI_FAILURE);
176 	}
177 
178 	if (i2c_client_register(dip, &unitp->seeprom_hdl) != I2C_SUCCESS) {
179 		cmn_err(CE_WARN, "i2c_client_register failed\n");
180 		ddi_remove_minor_node(dip, NULL);
181 		ddi_soft_state_free(seepromsoft_statep, instance);
182 
183 		return (DDI_FAILURE);
184 	}
185 
186 	if (strcmp(ddi_binding_name(dip), "i2c-at34c02") == 0) {
187 		unitp->seeprom_addrsize = AT34C02_ADDRSIZE;
188 		unitp->seeprom_memsize = AT34C02_MEMSIZE;
189 		unitp->seeprom_pagesize = AT34C02_PAGESIZE;
190 		unitp->seeprom_pagemask = AT34C02_PAGEMASK;
191 	} else {
192 		/*
193 		 * Default is i2c-at24c64
194 		 */
195 		unitp->seeprom_addrsize = AT24C64_ADDRSIZE;
196 		unitp->seeprom_memsize = AT24C64_MEMSIZE;
197 		unitp->seeprom_pagesize = AT24C64_PAGESIZE;
198 		unitp->seeprom_pagemask = AT24C64_PAGEMASK;
199 	}
200 	dev = makedevice(DDI_MAJOR_T_UNKNOWN, instance);
201 
202 	(void) ddi_prop_create(dev, dip, DDI_PROP_CANSLEEP, "size",
203 	    (caddr_t)&unitp->seeprom_memsize, sizeof (unitp->seeprom_memsize));
204 
205 	mutex_init(&unitp->seeprom_mutex, NULL, MUTEX_DRIVER, NULL);
206 	cv_init(&unitp->seeprom_cv, NULL, CV_DRIVER, NULL);
207 
208 	return (DDI_SUCCESS);
209 }
210 
211 static int
212 seeprom_attach(dev_info_t *dip, ddi_attach_cmd_t cmd)
213 {
214 	switch (cmd) {
215 	case DDI_ATTACH:
216 
217 		return (seeprom_do_attach(dip));
218 	case DDI_RESUME:
219 		/*
220 		 * No state to restore.
221 		 */
222 		return (DDI_SUCCESS);
223 	default:
224 
225 		return (DDI_FAILURE);
226 	}
227 }
228 
229 static int
230 seeprom_info(dev_info_t *dip, ddi_info_cmd_t infocmd, void *arg, void **result)
231 {
232 	_NOTE(ARGUNUSED(dip))
233 	struct seepromunit *unitp;
234 
235 	switch (infocmd) {
236 	case DDI_INFO_DEVT2DEVINFO:
237 		unitp = ddi_get_soft_state(seepromsoft_statep,
238 		    getminor((dev_t)arg));
239 		if (unitp == NULL) {
240 
241 			return (DDI_FAILURE);
242 		}
243 		*result = (void *)unitp->seeprom_dip;
244 
245 		return (DDI_SUCCESS);
246 	case DDI_INFO_DEVT2INSTANCE:
247 		*result = (void *)(uintptr_t)getminor((dev_t)arg);
248 
249 		return (DDI_SUCCESS);
250 	default:
251 		return (DDI_FAILURE);
252 	}
253 
254 }
255 
256 static int
257 seeprom_do_detach(dev_info_t *dip)
258 {
259 	struct seepromunit *unitp;
260 	int instance;
261 
262 	instance = ddi_get_instance(dip);
263 	unitp = ddi_get_soft_state(seepromsoft_statep, instance);
264 	i2c_client_unregister(unitp->seeprom_hdl);
265 	ddi_remove_minor_node(dip, NULL);
266 	mutex_destroy(&unitp->seeprom_mutex);
267 	cv_destroy(&unitp->seeprom_cv);
268 
269 	ddi_soft_state_free(seepromsoft_statep, instance);
270 
271 	return (DDI_SUCCESS);
272 }
273 
274 static int
275 seeprom_detach(dev_info_t *dip, ddi_detach_cmd_t cmd)
276 {
277 	switch (cmd) {
278 	case DDI_DETACH:
279 
280 		return (seeprom_do_detach(dip));
281 	case DDI_SUSPEND:
282 		/*
283 		 * No state to save.  IO will be blocked by nexus.
284 		 */
285 		return (DDI_SUCCESS);
286 	default:
287 
288 		return (DDI_FAILURE);
289 	}
290 }
291 
292 static int
293 seeprom_open(dev_t *devp, int flags, int otyp, cred_t *credp)
294 {
295 	_NOTE(ARGUNUSED(credp))
296 	struct seepromunit *unitp;
297 	int instance;
298 	int err = 0;
299 
300 	if (otyp != OTYP_CHR) {
301 
302 		return (EINVAL);
303 	}
304 
305 	instance = getminor(*devp);
306 
307 	unitp = (struct seepromunit *)
308 	    ddi_get_soft_state(seepromsoft_statep, instance);
309 
310 	if (unitp == NULL) {
311 
312 		return (ENXIO);
313 	}
314 
315 	mutex_enter(&unitp->seeprom_mutex);
316 
317 	if (flags & FEXCL) {
318 		if (unitp->seeprom_oflag != 0) {
319 			err = EBUSY;
320 		} else {
321 			unitp->seeprom_oflag = FEXCL;
322 		}
323 	} else {
324 		if (unitp->seeprom_oflag == FEXCL) {
325 			err = EBUSY;
326 		} else {
327 			unitp->seeprom_oflag = FOPEN;
328 		}
329 	}
330 
331 	mutex_exit(&unitp->seeprom_mutex);
332 
333 	return (err);
334 }
335 
336 static int
337 seeprom_close(dev_t dev, int flags, int otyp, cred_t *credp)
338 {
339 	_NOTE(ARGUNUSED(flags, otyp, credp))
340 	struct seepromunit *unitp;
341 	int instance;
342 
343 	instance = getminor(dev);
344 
345 	unitp = (struct seepromunit *)
346 	    ddi_get_soft_state(seepromsoft_statep, instance);
347 
348 	if (unitp == NULL) {
349 
350 		return (ENXIO);
351 	}
352 
353 	mutex_enter(&unitp->seeprom_mutex);
354 
355 	unitp->seeprom_oflag = 0;
356 
357 	mutex_exit(&unitp->seeprom_mutex);
358 
359 	return (DDI_SUCCESS);
360 }
361 
362 static int
363 seeprom_read(dev_t dev, struct uio *uiop, cred_t *cred_p)
364 {
365 	_NOTE(ARGUNUSED(cred_p))
366 	return (seeprom_io(dev, uiop, B_READ));
367 }
368 
369 static int
370 seeprom_write(dev_t dev, struct uio *uiop, cred_t *cred_p)
371 {
372 	_NOTE(ARGUNUSED(cred_p))
373 	return (seeprom_io(dev, uiop, B_WRITE));
374 }
375 
376 static int
377 seeprom_io(dev_t dev, struct uio *uiop, int rw)
378 {
379 	struct seepromunit *unitp;
380 	int instance = getminor(dev);
381 	int	seeprom_addr;
382 	int	bytes_to_rw;
383 	int	err = 0;
384 	int	current_xfer_len;
385 	int	actual_data_xfer;
386 	i2c_transfer_t *i2ctp = NULL;
387 
388 	unitp = (struct seepromunit *)
389 	    ddi_get_soft_state(seepromsoft_statep, instance);
390 
391 
392 	if (unitp == NULL) {
393 		return (ENXIO);
394 	}
395 
396 	if (uiop->uio_offset >= unitp->seeprom_memsize) {
397 		/*
398 		 * Exceeded seeprom size.
399 		 */
400 
401 		return (ENXIO);
402 	}
403 
404 	seeprom_addr = uiop->uio_offset;
405 
406 	if (uiop->uio_resid == 0) {
407 		return (0);
408 	}
409 
410 	bytes_to_rw = min(uiop->uio_resid,
411 	    unitp->seeprom_memsize - uiop->uio_offset);
412 	/*
413 	 * Serialize access here to prevent a transaction starting
414 	 * until after 20 ms delay if last operation was a write.
415 	 */
416 	mutex_enter(&unitp->seeprom_mutex);
417 	while ((unitp->seeprom_flags & SEEPROM_BUSY) == SEEPROM_BUSY) {
418 		if (cv_wait_sig(&unitp->seeprom_cv,
419 		    &unitp->seeprom_mutex) <= 0) {
420 			mutex_exit(&unitp->seeprom_mutex);
421 
422 			return (EINTR);
423 		}
424 	}
425 	unitp->seeprom_flags |= SEEPROM_BUSY;
426 	mutex_exit(&unitp->seeprom_mutex);
427 
428 	while ((bytes_to_rw != 0) && (err == 0)) {
429 		current_xfer_len = min(bytes_to_rw, unitp->seeprom_pagesize -
430 		    (seeprom_addr & unitp->seeprom_pagemask));
431 
432 		if (rw == B_WRITE) {
433 			if (i2ctp == NULL) {
434 				(void) i2c_transfer_alloc(unitp->seeprom_hdl,
435 				    &i2ctp,
436 				    unitp->seeprom_addrsize + current_xfer_len,
437 				    0,
438 				    I2C_SLEEP);
439 
440 				if ((err = uiomove(&i2ctp->i2c_wbuf[
441 				    unitp->seeprom_addrsize],
442 				    current_xfer_len, UIO_WRITE, uiop)) != 0) {
443 					i2c_transfer_free(unitp->seeprom_hdl,
444 					    i2ctp);
445 					break;
446 				}
447 				i2ctp->i2c_version = I2C_XFER_REV;
448 				i2ctp->i2c_flags = I2C_WR;
449 			} else {
450 
451 				/*
452 				 * not all bytes were sent in previous attempt.
453 				 * Adjust the write pointer to the unsent data.
454 				 */
455 				/*LINTED*/
456 				i2ctp->i2c_wbuf += actual_data_xfer;
457 				/*LINTED*/
458 				i2ctp->i2c_wlen -= actual_data_xfer;
459 			}
460 
461 			if (unitp->seeprom_addrsize == 2) {
462 				i2ctp->i2c_wbuf[0] = (seeprom_addr >> 8);
463 				i2ctp->i2c_wbuf[1] = (uchar_t)seeprom_addr;
464 			} else {
465 				i2ctp->i2c_wbuf[0] = (uchar_t)seeprom_addr;
466 			}
467 
468 			if ((err = i2c_transfer(unitp->seeprom_hdl, i2ctp)) !=
469 			    I2C_SUCCESS) {
470 				i2c_transfer_free(unitp->seeprom_hdl, i2ctp);
471 				break;
472 			}
473 
474 			actual_data_xfer = i2ctp->i2c_wlen -
475 			    i2ctp->i2c_w_resid - unitp->seeprom_addrsize;
476 
477 			if (i2ctp->i2c_w_resid == 0) {
478 				i2c_transfer_free(unitp->seeprom_hdl, i2ctp);
479 				i2ctp = NULL;
480 			}
481 			/*
482 			 * 20 ms(20000 Microsec) delay is required before
483 			 * issuing another transaction.  This enforces that
484 			 * wait.
485 			 */
486 			delay(drv_usectohz(20000));
487 		} else {
488 			/*
489 			 * SEEPROM read.  First write out the address to read.
490 			 */
491 			(void) i2c_transfer_alloc(unitp->seeprom_hdl, &i2ctp,
492 			    unitp->seeprom_addrsize, current_xfer_len,
493 			    I2C_SLEEP);
494 			i2ctp->i2c_version = I2C_XFER_REV;
495 
496 			if (unitp->seeprom_addrsize == 2) {
497 				i2ctp->i2c_wbuf[0] = (seeprom_addr >> 8);
498 				i2ctp->i2c_wbuf[1] = (uchar_t)seeprom_addr;
499 			} else {
500 				i2ctp->i2c_wbuf[0] = (uchar_t)seeprom_addr;
501 			}
502 
503 			i2ctp->i2c_flags = I2C_WR_RD;
504 
505 			if ((err = i2c_transfer(unitp->seeprom_hdl, i2ctp)) !=
506 			    I2C_SUCCESS) {
507 				i2c_transfer_free(unitp->seeprom_hdl, i2ctp);
508 				break;
509 			}
510 
511 			actual_data_xfer = i2ctp->i2c_rlen - i2ctp->i2c_r_resid;
512 
513 			err = uiomove(i2ctp->i2c_rbuf, actual_data_xfer,
514 			    UIO_READ, uiop);
515 			i2c_transfer_free(unitp->seeprom_hdl, i2ctp);
516 		}
517 
518 		bytes_to_rw -= actual_data_xfer;
519 		seeprom_addr += actual_data_xfer;
520 	}
521 
522 	mutex_enter(&unitp->seeprom_mutex);
523 	unitp->seeprom_flags = 0;
524 	cv_signal(&unitp->seeprom_cv);
525 	mutex_exit(&unitp->seeprom_mutex);
526 
527 	return (err);
528 }
529