xref: /openbmc/linux/drivers/mfd/si476x-i2c.c (revision aac5987a)
1 /*
2  * drivers/mfd/si476x-i2c.c -- Core device driver for si476x MFD
3  * device
4  *
5  * Copyright (C) 2012 Innovative Converged Devices(ICD)
6  * Copyright (C) 2013 Andrey Smirnov
7  *
8  * Author: Andrey Smirnov <andrew.smirnov@gmail.com>
9  *
10  * This program is free software; you can redistribute it and/or modify
11  * it under the terms of the GNU General Public License as published by
12  * the Free Software Foundation; version 2 of the License.
13  *
14  * This program is distributed in the hope that it will be useful, but
15  * WITHOUT ANY WARRANTY; without even the implied warranty of
16  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
17  * General Public License for more details.
18  *
19  */
20 #include <linux/module.h>
21 
22 #include <linux/slab.h>
23 #include <linux/interrupt.h>
24 #include <linux/delay.h>
25 #include <linux/gpio.h>
26 #include <linux/regulator/consumer.h>
27 #include <linux/i2c.h>
28 #include <linux/err.h>
29 
30 #include <linux/mfd/si476x-core.h>
31 
32 #define SI476X_MAX_IO_ERRORS		10
33 #define SI476X_DRIVER_RDS_FIFO_DEPTH	128
34 
35 /**
36  * si476x_core_config_pinmux() - pin function configuration function
37  *
38  * @core: Core device structure
39  *
40  * Configure the functions of the pins of the radio chip.
41  *
42  * The function returns zero in case of succes or negative error code
43  * otherwise.
44  */
45 static int si476x_core_config_pinmux(struct si476x_core *core)
46 {
47 	int err;
48 	dev_dbg(&core->client->dev, "Configuring pinmux\n");
49 	err = si476x_core_cmd_dig_audio_pin_cfg(core,
50 						core->pinmux.dclk,
51 						core->pinmux.dfs,
52 						core->pinmux.dout,
53 						core->pinmux.xout);
54 	if (err < 0) {
55 		dev_err(&core->client->dev,
56 			"Failed to configure digital audio pins(err = %d)\n",
57 			err);
58 		return err;
59 	}
60 
61 	err = si476x_core_cmd_zif_pin_cfg(core,
62 					  core->pinmux.iqclk,
63 					  core->pinmux.iqfs,
64 					  core->pinmux.iout,
65 					  core->pinmux.qout);
66 	if (err < 0) {
67 		dev_err(&core->client->dev,
68 			"Failed to configure ZIF pins(err = %d)\n",
69 			err);
70 		return err;
71 	}
72 
73 	err = si476x_core_cmd_ic_link_gpo_ctl_pin_cfg(core,
74 						      core->pinmux.icin,
75 						      core->pinmux.icip,
76 						      core->pinmux.icon,
77 						      core->pinmux.icop);
78 	if (err < 0) {
79 		dev_err(&core->client->dev,
80 			"Failed to configure IC-Link/GPO pins(err = %d)\n",
81 			err);
82 		return err;
83 	}
84 
85 	err = si476x_core_cmd_ana_audio_pin_cfg(core,
86 						core->pinmux.lrout);
87 	if (err < 0) {
88 		dev_err(&core->client->dev,
89 			"Failed to configure analog audio pins(err = %d)\n",
90 			err);
91 		return err;
92 	}
93 
94 	err = si476x_core_cmd_intb_pin_cfg(core,
95 					   core->pinmux.intb,
96 					   core->pinmux.a1);
97 	if (err < 0) {
98 		dev_err(&core->client->dev,
99 			"Failed to configure interrupt pins(err = %d)\n",
100 			err);
101 		return err;
102 	}
103 
104 	return 0;
105 }
106 
107 static inline void si476x_core_schedule_polling_work(struct si476x_core *core)
108 {
109 	schedule_delayed_work(&core->status_monitor,
110 			      usecs_to_jiffies(SI476X_STATUS_POLL_US));
111 }
112 
113 /**
114  * si476x_core_start() - early chip startup function
115  * @core: Core device structure
116  * @soft: When set, this flag forces "soft" startup, where "soft"
117  * power down is the one done by sending appropriate command instead
118  * of using reset pin of the tuner
119  *
120  * Perform required startup sequence to correctly power
121  * up the chip and perform initial configuration. It does the
122  * following sequence of actions:
123  *       1. Claims and enables the power supplies VD and VIO1 required
124  *          for I2C interface of the chip operation.
125  *       2. Waits for 100us, pulls the reset line up, enables irq,
126  *          waits for another 100us as it is specified by the
127  *          datasheet.
128  *       3. Sends 'POWER_UP' command to the device with all provided
129  *          information about power-up parameters.
130  *       4. Configures, pin multiplexor, disables digital audio and
131  *          configures interrupt sources.
132  *
133  * The function returns zero in case of succes or negative error code
134  * otherwise.
135  */
136 int si476x_core_start(struct si476x_core *core, bool soft)
137 {
138 	struct i2c_client *client = core->client;
139 	int err;
140 
141 	if (!soft) {
142 		if (gpio_is_valid(core->gpio_reset))
143 			gpio_set_value_cansleep(core->gpio_reset, 1);
144 
145 		if (client->irq)
146 			enable_irq(client->irq);
147 
148 		udelay(100);
149 
150 		if (!client->irq) {
151 			atomic_set(&core->is_alive, 1);
152 			si476x_core_schedule_polling_work(core);
153 		}
154 	} else {
155 		if (client->irq)
156 			enable_irq(client->irq);
157 		else {
158 			atomic_set(&core->is_alive, 1);
159 			si476x_core_schedule_polling_work(core);
160 		}
161 	}
162 
163 	err = si476x_core_cmd_power_up(core,
164 				       &core->power_up_parameters);
165 
166 	if (err < 0) {
167 		dev_err(&core->client->dev,
168 			"Power up failure(err = %d)\n",
169 			err);
170 		goto disable_irq;
171 	}
172 
173 	if (client->irq)
174 		atomic_set(&core->is_alive, 1);
175 
176 	err = si476x_core_config_pinmux(core);
177 	if (err < 0) {
178 		dev_err(&core->client->dev,
179 			"Failed to configure pinmux(err = %d)\n",
180 			err);
181 		goto disable_irq;
182 	}
183 
184 	if (client->irq) {
185 		err = regmap_write(core->regmap,
186 				   SI476X_PROP_INT_CTL_ENABLE,
187 				   SI476X_RDSIEN |
188 				   SI476X_STCIEN |
189 				   SI476X_CTSIEN);
190 		if (err < 0) {
191 			dev_err(&core->client->dev,
192 				"Failed to configure interrupt sources"
193 				"(err = %d)\n", err);
194 			goto disable_irq;
195 		}
196 	}
197 
198 	return 0;
199 
200 disable_irq:
201 	if (err == -ENODEV)
202 		atomic_set(&core->is_alive, 0);
203 
204 	if (client->irq)
205 		disable_irq(client->irq);
206 	else
207 		cancel_delayed_work_sync(&core->status_monitor);
208 
209 	if (gpio_is_valid(core->gpio_reset))
210 		gpio_set_value_cansleep(core->gpio_reset, 0);
211 
212 	return err;
213 }
214 EXPORT_SYMBOL_GPL(si476x_core_start);
215 
216 /**
217  * si476x_core_stop() - chip power-down function
218  * @core: Core device structure
219  * @soft: When set, function sends a POWER_DOWN command instead of
220  * bringing reset line low
221  *
222  * Power down the chip by performing following actions:
223  * 1. Disable IRQ or stop the polling worker
224  * 2. Send the POWER_DOWN command if the power down is soft or bring
225  *    reset line low if not.
226  *
227  * The function returns zero in case of succes or negative error code
228  * otherwise.
229  */
230 int si476x_core_stop(struct si476x_core *core, bool soft)
231 {
232 	int err = 0;
233 	atomic_set(&core->is_alive, 0);
234 
235 	if (soft) {
236 		/* TODO: This probably shoud be a configurable option,
237 		 * so it is possible to have the chips keep their
238 		 * oscillators running
239 		 */
240 		struct si476x_power_down_args args = {
241 			.xosc = false,
242 		};
243 		err = si476x_core_cmd_power_down(core, &args);
244 	}
245 
246 	/* We couldn't disable those before
247 	 * 'si476x_core_cmd_power_down' since we expect to get CTS
248 	 * interrupt */
249 	if (core->client->irq)
250 		disable_irq(core->client->irq);
251 	else
252 		cancel_delayed_work_sync(&core->status_monitor);
253 
254 	if (!soft) {
255 		if (gpio_is_valid(core->gpio_reset))
256 			gpio_set_value_cansleep(core->gpio_reset, 0);
257 	}
258 	return err;
259 }
260 EXPORT_SYMBOL_GPL(si476x_core_stop);
261 
262 /**
263  * si476x_core_set_power_state() - set the level at which the power is
264  * supplied for the chip.
265  * @core: Core device structure
266  * @next_state: enum si476x_power_state describing power state to
267  *              switch to.
268  *
269  * Switch on all the required power supplies
270  *
271  * This function returns 0 in case of suvccess and negative error code
272  * otherwise.
273  */
274 int si476x_core_set_power_state(struct si476x_core *core,
275 				enum si476x_power_state next_state)
276 {
277 	/*
278 	   It is not clear form the datasheet if it is possible to
279 	   work with device if not all power domains are operational.
280 	   So for now the power-up policy is "power-up all the things!"
281 	 */
282 	int err = 0;
283 
284 	if (core->power_state == SI476X_POWER_INCONSISTENT) {
285 		dev_err(&core->client->dev,
286 			"The device in inconsistent power state\n");
287 		return -EINVAL;
288 	}
289 
290 	if (next_state != core->power_state) {
291 		switch (next_state) {
292 		case SI476X_POWER_UP_FULL:
293 			err = regulator_bulk_enable(ARRAY_SIZE(core->supplies),
294 						    core->supplies);
295 			if (err < 0) {
296 				core->power_state = SI476X_POWER_INCONSISTENT;
297 				break;
298 			}
299 			/*
300 			 * Startup timing diagram recommends to have a
301 			 * 100 us delay between enabling of the power
302 			 * supplies and turning the tuner on.
303 			 */
304 			udelay(100);
305 
306 			err = si476x_core_start(core, false);
307 			if (err < 0)
308 				goto disable_regulators;
309 
310 			core->power_state = next_state;
311 			break;
312 
313 		case SI476X_POWER_DOWN:
314 			core->power_state = next_state;
315 			err = si476x_core_stop(core, false);
316 			if (err < 0)
317 				core->power_state = SI476X_POWER_INCONSISTENT;
318 disable_regulators:
319 			err = regulator_bulk_disable(ARRAY_SIZE(core->supplies),
320 						     core->supplies);
321 			if (err < 0)
322 				core->power_state = SI476X_POWER_INCONSISTENT;
323 			break;
324 		default:
325 			BUG();
326 		}
327 	}
328 
329 	return err;
330 }
331 EXPORT_SYMBOL_GPL(si476x_core_set_power_state);
332 
333 /**
334  * si476x_core_report_drainer_stop() - mark the completion of the RDS
335  * buffer drain porcess by the worker.
336  *
337  * @core: Core device structure
338  */
339 static inline void si476x_core_report_drainer_stop(struct si476x_core *core)
340 {
341 	mutex_lock(&core->rds_drainer_status_lock);
342 	core->rds_drainer_is_working = false;
343 	mutex_unlock(&core->rds_drainer_status_lock);
344 }
345 
346 /**
347  * si476x_core_start_rds_drainer_once() - start RDS drainer worker if
348  * ther is none working, do nothing otherwise
349  *
350  * @core: Datastructure corresponding to the chip.
351  */
352 static inline void si476x_core_start_rds_drainer_once(struct si476x_core *core)
353 {
354 	mutex_lock(&core->rds_drainer_status_lock);
355 	if (!core->rds_drainer_is_working) {
356 		core->rds_drainer_is_working = true;
357 		schedule_work(&core->rds_fifo_drainer);
358 	}
359 	mutex_unlock(&core->rds_drainer_status_lock);
360 }
361 /**
362  * si476x_drain_rds_fifo() - RDS buffer drainer.
363  * @work: struct work_struct being ppassed to the function by the
364  * kernel.
365  *
366  * Drain the contents of the RDS FIFO of
367  */
368 static void si476x_core_drain_rds_fifo(struct work_struct *work)
369 {
370 	int err;
371 
372 	struct si476x_core *core = container_of(work, struct si476x_core,
373 						rds_fifo_drainer);
374 
375 	struct si476x_rds_status_report report;
376 
377 	si476x_core_lock(core);
378 	err = si476x_core_cmd_fm_rds_status(core, true, false, false, &report);
379 	if (!err) {
380 		int i = report.rdsfifoused;
381 		dev_dbg(&core->client->dev,
382 			"%d elements in RDS FIFO. Draining.\n", i);
383 		for (; i > 0; --i) {
384 			err = si476x_core_cmd_fm_rds_status(core, false, false,
385 							    (i == 1), &report);
386 			if (err < 0)
387 				goto unlock;
388 
389 			kfifo_in(&core->rds_fifo, report.rds,
390 				 sizeof(report.rds));
391 			dev_dbg(&core->client->dev, "RDS data:\n %*ph\n",
392 				(int)sizeof(report.rds), report.rds);
393 		}
394 		dev_dbg(&core->client->dev, "Drrrrained!\n");
395 		wake_up_interruptible(&core->rds_read_queue);
396 	}
397 
398 unlock:
399 	si476x_core_unlock(core);
400 	si476x_core_report_drainer_stop(core);
401 }
402 
403 /**
404  * si476x_core_pronounce_dead()
405  *
406  * @core: Core device structure
407  *
408  * Mark the device as being dead and wake up all potentially waiting
409  * threads of execution.
410  *
411  */
412 static void si476x_core_pronounce_dead(struct si476x_core *core)
413 {
414 	dev_info(&core->client->dev, "Core device is dead.\n");
415 
416 	atomic_set(&core->is_alive, 0);
417 
418 	/* Wake up al possible waiting processes */
419 	wake_up_interruptible(&core->rds_read_queue);
420 
421 	atomic_set(&core->cts, 1);
422 	wake_up(&core->command);
423 
424 	atomic_set(&core->stc, 1);
425 	wake_up(&core->tuning);
426 }
427 
428 /**
429  * si476x_core_i2c_xfer()
430  *
431  * @core: Core device structure
432  * @type: Transfer type
433  * @buf: Transfer buffer for/with data
434  * @count: Transfer buffer size
435  *
436  * Perfrom and I2C transfer(either read or write) and keep a counter
437  * of I/O errors. If the error counter rises above the threshold
438  * pronounce device dead.
439  *
440  * The function returns zero on succes or negative error code on
441  * failure.
442  */
443 int si476x_core_i2c_xfer(struct si476x_core *core,
444 		    enum si476x_i2c_type type,
445 		    char *buf, int count)
446 {
447 	static int io_errors_count;
448 	int err;
449 	if (type == SI476X_I2C_SEND)
450 		err = i2c_master_send(core->client, buf, count);
451 	else
452 		err = i2c_master_recv(core->client, buf, count);
453 
454 	if (err < 0) {
455 		if (io_errors_count++ > SI476X_MAX_IO_ERRORS)
456 			si476x_core_pronounce_dead(core);
457 	} else {
458 		io_errors_count = 0;
459 	}
460 
461 	return err;
462 }
463 EXPORT_SYMBOL_GPL(si476x_core_i2c_xfer);
464 
465 /**
466  * si476x_get_status()
467  * @core: Core device structure
468  *
469  * Get the status byte of the core device by berforming one byte I2C
470  * read.
471  *
472  * The function returns a status value or a negative error code on
473  * error.
474  */
475 static int si476x_core_get_status(struct si476x_core *core)
476 {
477 	u8 response;
478 	int err = si476x_core_i2c_xfer(core, SI476X_I2C_RECV,
479 				  &response, sizeof(response));
480 
481 	return (err < 0) ? err : response;
482 }
483 
484 /**
485  * si476x_get_and_signal_status() - IRQ dispatcher
486  * @core: Core device structure
487  *
488  * Dispatch the arrived interrupt request based on the value of the
489  * status byte reported by the tuner.
490  *
491  */
492 static void si476x_core_get_and_signal_status(struct si476x_core *core)
493 {
494 	int status = si476x_core_get_status(core);
495 	if (status < 0) {
496 		dev_err(&core->client->dev, "Failed to get status\n");
497 		return;
498 	}
499 
500 	if (status & SI476X_CTS) {
501 		/* Unfortunately completions could not be used for
502 		 * signalling CTS since this flag cannot be cleared
503 		 * in status byte, and therefore once it becomes true
504 		 * multiple calls to 'complete' would cause the
505 		 * commands following the current one to be completed
506 		 * before they actually are */
507 		dev_dbg(&core->client->dev, "[interrupt] CTSINT\n");
508 		atomic_set(&core->cts, 1);
509 		wake_up(&core->command);
510 	}
511 
512 	if (status & SI476X_FM_RDS_INT) {
513 		dev_dbg(&core->client->dev, "[interrupt] RDSINT\n");
514 		si476x_core_start_rds_drainer_once(core);
515 	}
516 
517 	if (status & SI476X_STC_INT) {
518 		dev_dbg(&core->client->dev, "[interrupt] STCINT\n");
519 		atomic_set(&core->stc, 1);
520 		wake_up(&core->tuning);
521 	}
522 }
523 
524 static void si476x_core_poll_loop(struct work_struct *work)
525 {
526 	struct si476x_core *core = SI476X_WORK_TO_CORE(work);
527 
528 	si476x_core_get_and_signal_status(core);
529 
530 	if (atomic_read(&core->is_alive))
531 		si476x_core_schedule_polling_work(core);
532 }
533 
534 static irqreturn_t si476x_core_interrupt(int irq, void *dev)
535 {
536 	struct si476x_core *core = dev;
537 
538 	si476x_core_get_and_signal_status(core);
539 
540 	return IRQ_HANDLED;
541 }
542 
543 /**
544  * si476x_firmware_version_to_revision()
545  * @core: Core device structure
546  * @major:  Firmware major number
547  * @minor1: Firmware first minor number
548  * @minor2: Firmware second minor number
549  *
550  * Convert a chip's firmware version number into an offset that later
551  * will be used to as offset in "vtable" of tuner functions
552  *
553  * This function returns a positive offset in case of success and a -1
554  * in case of failure.
555  */
556 static int si476x_core_fwver_to_revision(struct si476x_core *core,
557 					 int func, int major,
558 					 int minor1, int minor2)
559 {
560 	switch (func) {
561 	case SI476X_FUNC_FM_RECEIVER:
562 		switch (major) {
563 		case 5:
564 			return SI476X_REVISION_A10;
565 		case 8:
566 			return SI476X_REVISION_A20;
567 		case 10:
568 			return SI476X_REVISION_A30;
569 		default:
570 			goto unknown_revision;
571 		}
572 	case SI476X_FUNC_AM_RECEIVER:
573 		switch (major) {
574 		case 5:
575 			return SI476X_REVISION_A10;
576 		case 7:
577 			return SI476X_REVISION_A20;
578 		case 9:
579 			return SI476X_REVISION_A30;
580 		default:
581 			goto unknown_revision;
582 		}
583 	case SI476X_FUNC_WB_RECEIVER:
584 		switch (major) {
585 		case 3:
586 			return SI476X_REVISION_A10;
587 		case 5:
588 			return SI476X_REVISION_A20;
589 		case 7:
590 			return SI476X_REVISION_A30;
591 		default:
592 			goto unknown_revision;
593 		}
594 	case SI476X_FUNC_BOOTLOADER:
595 	default:		/* FALLTHROUG */
596 		BUG();
597 		return -1;
598 	}
599 
600 unknown_revision:
601 	dev_err(&core->client->dev,
602 		"Unsupported version of the firmware: %d.%d.%d, "
603 		"reverting to A10 compatible functions\n",
604 		major, minor1, minor2);
605 
606 	return SI476X_REVISION_A10;
607 }
608 
609 /**
610  * si476x_get_revision_info()
611  * @core: Core device structure
612  *
613  * Get the firmware version number of the device. It is done in
614  * following three steps:
615  *    1. Power-up the device
616  *    2. Send the 'FUNC_INFO' command
617  *    3. Powering the device down.
618  *
619  * The function return zero on success and a negative error code on
620  * failure.
621  */
622 static int si476x_core_get_revision_info(struct si476x_core *core)
623 {
624 	int rval;
625 	struct si476x_func_info info;
626 
627 	si476x_core_lock(core);
628 	rval = si476x_core_set_power_state(core, SI476X_POWER_UP_FULL);
629 	if (rval < 0)
630 		goto exit;
631 
632 	rval = si476x_core_cmd_func_info(core, &info);
633 	if (rval < 0)
634 		goto power_down;
635 
636 	core->revision = si476x_core_fwver_to_revision(core, info.func,
637 						       info.firmware.major,
638 						       info.firmware.minor[0],
639 						       info.firmware.minor[1]);
640 power_down:
641 	si476x_core_set_power_state(core, SI476X_POWER_DOWN);
642 exit:
643 	si476x_core_unlock(core);
644 
645 	return rval;
646 }
647 
648 bool si476x_core_has_am(struct si476x_core *core)
649 {
650 	return core->chip_id == SI476X_CHIP_SI4761 ||
651 		core->chip_id == SI476X_CHIP_SI4764;
652 }
653 EXPORT_SYMBOL_GPL(si476x_core_has_am);
654 
655 bool si476x_core_has_diversity(struct si476x_core *core)
656 {
657 	return core->chip_id == SI476X_CHIP_SI4764;
658 }
659 EXPORT_SYMBOL_GPL(si476x_core_has_diversity);
660 
661 bool si476x_core_is_a_secondary_tuner(struct si476x_core *core)
662 {
663 	return si476x_core_has_diversity(core) &&
664 		(core->diversity_mode == SI476X_PHDIV_SECONDARY_ANTENNA ||
665 		 core->diversity_mode == SI476X_PHDIV_SECONDARY_COMBINING);
666 }
667 EXPORT_SYMBOL_GPL(si476x_core_is_a_secondary_tuner);
668 
669 bool si476x_core_is_a_primary_tuner(struct si476x_core *core)
670 {
671 	return si476x_core_has_diversity(core) &&
672 		(core->diversity_mode == SI476X_PHDIV_PRIMARY_ANTENNA ||
673 		 core->diversity_mode == SI476X_PHDIV_PRIMARY_COMBINING);
674 }
675 EXPORT_SYMBOL_GPL(si476x_core_is_a_primary_tuner);
676 
677 bool si476x_core_is_in_am_receiver_mode(struct si476x_core *core)
678 {
679 	return si476x_core_has_am(core) &&
680 		(core->power_up_parameters.func == SI476X_FUNC_AM_RECEIVER);
681 }
682 EXPORT_SYMBOL_GPL(si476x_core_is_in_am_receiver_mode);
683 
684 bool si476x_core_is_powered_up(struct si476x_core *core)
685 {
686 	return core->power_state == SI476X_POWER_UP_FULL;
687 }
688 EXPORT_SYMBOL_GPL(si476x_core_is_powered_up);
689 
690 static int si476x_core_probe(struct i2c_client *client,
691 			     const struct i2c_device_id *id)
692 {
693 	int rval;
694 	struct si476x_core          *core;
695 	struct si476x_platform_data *pdata;
696 	struct mfd_cell *cell;
697 	int              cell_num;
698 
699 	core = devm_kzalloc(&client->dev, sizeof(*core), GFP_KERNEL);
700 	if (!core) {
701 		dev_err(&client->dev,
702 			"failed to allocate 'struct si476x_core'\n");
703 		return -ENOMEM;
704 	}
705 	core->client = client;
706 
707 	core->regmap = devm_regmap_init_si476x(core);
708 	if (IS_ERR(core->regmap)) {
709 		rval = PTR_ERR(core->regmap);
710 		dev_err(&client->dev,
711 			"Failed to allocate register map: %d\n",
712 			rval);
713 		return rval;
714 	}
715 
716 	i2c_set_clientdata(client, core);
717 
718 	atomic_set(&core->is_alive, 0);
719 	core->power_state = SI476X_POWER_DOWN;
720 
721 	pdata = dev_get_platdata(&client->dev);
722 	if (pdata) {
723 		memcpy(&core->power_up_parameters,
724 		       &pdata->power_up_parameters,
725 		       sizeof(core->power_up_parameters));
726 
727 		core->gpio_reset = -1;
728 		if (gpio_is_valid(pdata->gpio_reset)) {
729 			rval = gpio_request(pdata->gpio_reset, "si476x reset");
730 			if (rval) {
731 				dev_err(&client->dev,
732 					"Failed to request gpio: %d\n", rval);
733 				return rval;
734 			}
735 			core->gpio_reset = pdata->gpio_reset;
736 			gpio_direction_output(core->gpio_reset, 0);
737 		}
738 
739 		core->diversity_mode = pdata->diversity_mode;
740 		memcpy(&core->pinmux, &pdata->pinmux,
741 		       sizeof(struct si476x_pinmux));
742 	} else {
743 		dev_err(&client->dev, "No platform data provided\n");
744 		return -EINVAL;
745 	}
746 
747 	core->supplies[0].supply = "vd";
748 	core->supplies[1].supply = "va";
749 	core->supplies[2].supply = "vio1";
750 	core->supplies[3].supply = "vio2";
751 
752 	rval = devm_regulator_bulk_get(&client->dev,
753 				       ARRAY_SIZE(core->supplies),
754 				       core->supplies);
755 	if (rval) {
756 		dev_err(&client->dev, "Failed to get all of the regulators\n");
757 		goto free_gpio;
758 	}
759 
760 	mutex_init(&core->cmd_lock);
761 	init_waitqueue_head(&core->command);
762 	init_waitqueue_head(&core->tuning);
763 
764 	rval = kfifo_alloc(&core->rds_fifo,
765 			   SI476X_DRIVER_RDS_FIFO_DEPTH *
766 			   sizeof(struct v4l2_rds_data),
767 			   GFP_KERNEL);
768 	if (rval) {
769 		dev_err(&client->dev, "Could not allocate the FIFO\n");
770 		goto free_gpio;
771 	}
772 	mutex_init(&core->rds_drainer_status_lock);
773 	init_waitqueue_head(&core->rds_read_queue);
774 	INIT_WORK(&core->rds_fifo_drainer, si476x_core_drain_rds_fifo);
775 
776 	if (client->irq) {
777 		rval = devm_request_threaded_irq(&client->dev,
778 						 client->irq, NULL,
779 						 si476x_core_interrupt,
780 						 IRQF_TRIGGER_FALLING |
781 						 IRQF_ONESHOT,
782 						 client->name, core);
783 		if (rval < 0) {
784 			dev_err(&client->dev, "Could not request IRQ %d\n",
785 				client->irq);
786 			goto free_kfifo;
787 		}
788 		disable_irq(client->irq);
789 		dev_dbg(&client->dev, "IRQ requested.\n");
790 
791 		core->rds_fifo_depth = 20;
792 	} else {
793 		INIT_DELAYED_WORK(&core->status_monitor,
794 				  si476x_core_poll_loop);
795 		dev_info(&client->dev,
796 			 "No IRQ number specified, will use polling\n");
797 
798 		core->rds_fifo_depth = 5;
799 	}
800 
801 	core->chip_id = id->driver_data;
802 
803 	rval = si476x_core_get_revision_info(core);
804 	if (rval < 0) {
805 		rval = -ENODEV;
806 		goto free_kfifo;
807 	}
808 
809 	cell_num = 0;
810 
811 	cell = &core->cells[SI476X_RADIO_CELL];
812 	cell->name = "si476x-radio";
813 	cell_num++;
814 
815 #ifdef CONFIG_SND_SOC_SI476X
816 	if ((core->chip_id == SI476X_CHIP_SI4761 ||
817 	     core->chip_id == SI476X_CHIP_SI4764)	&&
818 	    core->pinmux.dclk == SI476X_DCLK_DAUDIO     &&
819 	    core->pinmux.dfs  == SI476X_DFS_DAUDIO      &&
820 	    core->pinmux.dout == SI476X_DOUT_I2S_OUTPUT &&
821 	    core->pinmux.xout == SI476X_XOUT_TRISTATE) {
822 		cell = &core->cells[SI476X_CODEC_CELL];
823 		cell->name          = "si476x-codec";
824 		cell_num++;
825 	}
826 #endif
827 	rval = mfd_add_devices(&client->dev,
828 			       (client->adapter->nr << 8) + client->addr,
829 			       core->cells, cell_num,
830 			       NULL, 0, NULL);
831 	if (!rval)
832 		return 0;
833 
834 free_kfifo:
835 	kfifo_free(&core->rds_fifo);
836 
837 free_gpio:
838 	if (gpio_is_valid(core->gpio_reset))
839 		gpio_free(core->gpio_reset);
840 
841 	return rval;
842 }
843 
844 static int si476x_core_remove(struct i2c_client *client)
845 {
846 	struct si476x_core *core = i2c_get_clientdata(client);
847 
848 	si476x_core_pronounce_dead(core);
849 	mfd_remove_devices(&client->dev);
850 
851 	if (client->irq)
852 		disable_irq(client->irq);
853 	else
854 		cancel_delayed_work_sync(&core->status_monitor);
855 
856 	kfifo_free(&core->rds_fifo);
857 
858 	if (gpio_is_valid(core->gpio_reset))
859 		gpio_free(core->gpio_reset);
860 
861 	return 0;
862 }
863 
864 
865 static const struct i2c_device_id si476x_id[] = {
866 	{ "si4761", SI476X_CHIP_SI4761 },
867 	{ "si4764", SI476X_CHIP_SI4764 },
868 	{ "si4768", SI476X_CHIP_SI4768 },
869 	{ },
870 };
871 MODULE_DEVICE_TABLE(i2c, si476x_id);
872 
873 static struct i2c_driver si476x_core_driver = {
874 	.driver		= {
875 		.name	= "si476x-core",
876 	},
877 	.probe		= si476x_core_probe,
878 	.remove         = si476x_core_remove,
879 	.id_table       = si476x_id,
880 };
881 module_i2c_driver(si476x_core_driver);
882 
883 
884 MODULE_AUTHOR("Andrey Smirnov <andrew.smirnov@gmail.com>");
885 MODULE_DESCRIPTION("Si4761/64/68 AM/FM MFD core device driver");
886 MODULE_LICENSE("GPL");
887