xref: /openbmc/linux/drivers/mfd/si476x-i2c.c (revision 2d99a7ec)
1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3  * drivers/mfd/si476x-i2c.c -- Core device driver for si476x MFD
4  * device
5  *
6  * Copyright (C) 2012 Innovative Converged Devices(ICD)
7  * Copyright (C) 2013 Andrey Smirnov
8  *
9  * Author: Andrey Smirnov <andrew.smirnov@gmail.com>
10  */
11 #include <linux/module.h>
12 
13 #include <linux/slab.h>
14 #include <linux/interrupt.h>
15 #include <linux/delay.h>
16 #include <linux/gpio.h>
17 #include <linux/regulator/consumer.h>
18 #include <linux/i2c.h>
19 #include <linux/err.h>
20 
21 #include <linux/mfd/si476x-core.h>
22 
23 #define SI476X_MAX_IO_ERRORS		10
24 #define SI476X_DRIVER_RDS_FIFO_DEPTH	128
25 
26 /**
27  * si476x_core_config_pinmux() - pin function configuration function
28  *
29  * @core: Core device structure
30  *
31  * Configure the functions of the pins of the radio chip.
32  *
33  * The function returns zero in case of succes or negative error code
34  * otherwise.
35  */
36 static int si476x_core_config_pinmux(struct si476x_core *core)
37 {
38 	int err;
39 	dev_dbg(&core->client->dev, "Configuring pinmux\n");
40 	err = si476x_core_cmd_dig_audio_pin_cfg(core,
41 						core->pinmux.dclk,
42 						core->pinmux.dfs,
43 						core->pinmux.dout,
44 						core->pinmux.xout);
45 	if (err < 0) {
46 		dev_err(&core->client->dev,
47 			"Failed to configure digital audio pins(err = %d)\n",
48 			err);
49 		return err;
50 	}
51 
52 	err = si476x_core_cmd_zif_pin_cfg(core,
53 					  core->pinmux.iqclk,
54 					  core->pinmux.iqfs,
55 					  core->pinmux.iout,
56 					  core->pinmux.qout);
57 	if (err < 0) {
58 		dev_err(&core->client->dev,
59 			"Failed to configure ZIF pins(err = %d)\n",
60 			err);
61 		return err;
62 	}
63 
64 	err = si476x_core_cmd_ic_link_gpo_ctl_pin_cfg(core,
65 						      core->pinmux.icin,
66 						      core->pinmux.icip,
67 						      core->pinmux.icon,
68 						      core->pinmux.icop);
69 	if (err < 0) {
70 		dev_err(&core->client->dev,
71 			"Failed to configure IC-Link/GPO pins(err = %d)\n",
72 			err);
73 		return err;
74 	}
75 
76 	err = si476x_core_cmd_ana_audio_pin_cfg(core,
77 						core->pinmux.lrout);
78 	if (err < 0) {
79 		dev_err(&core->client->dev,
80 			"Failed to configure analog audio pins(err = %d)\n",
81 			err);
82 		return err;
83 	}
84 
85 	err = si476x_core_cmd_intb_pin_cfg(core,
86 					   core->pinmux.intb,
87 					   core->pinmux.a1);
88 	if (err < 0) {
89 		dev_err(&core->client->dev,
90 			"Failed to configure interrupt pins(err = %d)\n",
91 			err);
92 		return err;
93 	}
94 
95 	return 0;
96 }
97 
98 static inline void si476x_core_schedule_polling_work(struct si476x_core *core)
99 {
100 	schedule_delayed_work(&core->status_monitor,
101 			      usecs_to_jiffies(SI476X_STATUS_POLL_US));
102 }
103 
104 /**
105  * si476x_core_start() - early chip startup function
106  * @core: Core device structure
107  * @soft: When set, this flag forces "soft" startup, where "soft"
108  * power down is the one done by sending appropriate command instead
109  * of using reset pin of the tuner
110  *
111  * Perform required startup sequence to correctly power
112  * up the chip and perform initial configuration. It does the
113  * following sequence of actions:
114  *       1. Claims and enables the power supplies VD and VIO1 required
115  *          for I2C interface of the chip operation.
116  *       2. Waits for 100us, pulls the reset line up, enables irq,
117  *          waits for another 100us as it is specified by the
118  *          datasheet.
119  *       3. Sends 'POWER_UP' command to the device with all provided
120  *          information about power-up parameters.
121  *       4. Configures, pin multiplexor, disables digital audio and
122  *          configures interrupt sources.
123  *
124  * The function returns zero in case of succes or negative error code
125  * otherwise.
126  */
127 int si476x_core_start(struct si476x_core *core, bool soft)
128 {
129 	struct i2c_client *client = core->client;
130 	int err;
131 
132 	if (!soft) {
133 		if (gpio_is_valid(core->gpio_reset))
134 			gpio_set_value_cansleep(core->gpio_reset, 1);
135 
136 		if (client->irq)
137 			enable_irq(client->irq);
138 
139 		udelay(100);
140 
141 		if (!client->irq) {
142 			atomic_set(&core->is_alive, 1);
143 			si476x_core_schedule_polling_work(core);
144 		}
145 	} else {
146 		if (client->irq)
147 			enable_irq(client->irq);
148 		else {
149 			atomic_set(&core->is_alive, 1);
150 			si476x_core_schedule_polling_work(core);
151 		}
152 	}
153 
154 	err = si476x_core_cmd_power_up(core,
155 				       &core->power_up_parameters);
156 
157 	if (err < 0) {
158 		dev_err(&core->client->dev,
159 			"Power up failure(err = %d)\n",
160 			err);
161 		goto disable_irq;
162 	}
163 
164 	if (client->irq)
165 		atomic_set(&core->is_alive, 1);
166 
167 	err = si476x_core_config_pinmux(core);
168 	if (err < 0) {
169 		dev_err(&core->client->dev,
170 			"Failed to configure pinmux(err = %d)\n",
171 			err);
172 		goto disable_irq;
173 	}
174 
175 	if (client->irq) {
176 		err = regmap_write(core->regmap,
177 				   SI476X_PROP_INT_CTL_ENABLE,
178 				   SI476X_RDSIEN |
179 				   SI476X_STCIEN |
180 				   SI476X_CTSIEN);
181 		if (err < 0) {
182 			dev_err(&core->client->dev,
183 				"Failed to configure interrupt sources"
184 				"(err = %d)\n", err);
185 			goto disable_irq;
186 		}
187 	}
188 
189 	return 0;
190 
191 disable_irq:
192 	if (err == -ENODEV)
193 		atomic_set(&core->is_alive, 0);
194 
195 	if (client->irq)
196 		disable_irq(client->irq);
197 	else
198 		cancel_delayed_work_sync(&core->status_monitor);
199 
200 	if (gpio_is_valid(core->gpio_reset))
201 		gpio_set_value_cansleep(core->gpio_reset, 0);
202 
203 	return err;
204 }
205 EXPORT_SYMBOL_GPL(si476x_core_start);
206 
207 /**
208  * si476x_core_stop() - chip power-down function
209  * @core: Core device structure
210  * @soft: When set, function sends a POWER_DOWN command instead of
211  * bringing reset line low
212  *
213  * Power down the chip by performing following actions:
214  * 1. Disable IRQ or stop the polling worker
215  * 2. Send the POWER_DOWN command if the power down is soft or bring
216  *    reset line low if not.
217  *
218  * The function returns zero in case of succes or negative error code
219  * otherwise.
220  */
221 int si476x_core_stop(struct si476x_core *core, bool soft)
222 {
223 	int err = 0;
224 	atomic_set(&core->is_alive, 0);
225 
226 	if (soft) {
227 		/* TODO: This probably shoud be a configurable option,
228 		 * so it is possible to have the chips keep their
229 		 * oscillators running
230 		 */
231 		struct si476x_power_down_args args = {
232 			.xosc = false,
233 		};
234 		err = si476x_core_cmd_power_down(core, &args);
235 	}
236 
237 	/* We couldn't disable those before
238 	 * 'si476x_core_cmd_power_down' since we expect to get CTS
239 	 * interrupt */
240 	if (core->client->irq)
241 		disable_irq(core->client->irq);
242 	else
243 		cancel_delayed_work_sync(&core->status_monitor);
244 
245 	if (!soft) {
246 		if (gpio_is_valid(core->gpio_reset))
247 			gpio_set_value_cansleep(core->gpio_reset, 0);
248 	}
249 	return err;
250 }
251 EXPORT_SYMBOL_GPL(si476x_core_stop);
252 
253 /**
254  * si476x_core_set_power_state() - set the level at which the power is
255  * supplied for the chip.
256  * @core: Core device structure
257  * @next_state: enum si476x_power_state describing power state to
258  *              switch to.
259  *
260  * Switch on all the required power supplies
261  *
262  * This function returns 0 in case of suvccess and negative error code
263  * otherwise.
264  */
265 int si476x_core_set_power_state(struct si476x_core *core,
266 				enum si476x_power_state next_state)
267 {
268 	/*
269 	   It is not clear form the datasheet if it is possible to
270 	   work with device if not all power domains are operational.
271 	   So for now the power-up policy is "power-up all the things!"
272 	 */
273 	int err = 0;
274 
275 	if (core->power_state == SI476X_POWER_INCONSISTENT) {
276 		dev_err(&core->client->dev,
277 			"The device in inconsistent power state\n");
278 		return -EINVAL;
279 	}
280 
281 	if (next_state != core->power_state) {
282 		switch (next_state) {
283 		case SI476X_POWER_UP_FULL:
284 			err = regulator_bulk_enable(ARRAY_SIZE(core->supplies),
285 						    core->supplies);
286 			if (err < 0) {
287 				core->power_state = SI476X_POWER_INCONSISTENT;
288 				break;
289 			}
290 			/*
291 			 * Startup timing diagram recommends to have a
292 			 * 100 us delay between enabling of the power
293 			 * supplies and turning the tuner on.
294 			 */
295 			udelay(100);
296 
297 			err = si476x_core_start(core, false);
298 			if (err < 0)
299 				goto disable_regulators;
300 
301 			core->power_state = next_state;
302 			break;
303 
304 		case SI476X_POWER_DOWN:
305 			core->power_state = next_state;
306 			err = si476x_core_stop(core, false);
307 			if (err < 0)
308 				core->power_state = SI476X_POWER_INCONSISTENT;
309 disable_regulators:
310 			err = regulator_bulk_disable(ARRAY_SIZE(core->supplies),
311 						     core->supplies);
312 			if (err < 0)
313 				core->power_state = SI476X_POWER_INCONSISTENT;
314 			break;
315 		default:
316 			BUG();
317 		}
318 	}
319 
320 	return err;
321 }
322 EXPORT_SYMBOL_GPL(si476x_core_set_power_state);
323 
324 /**
325  * si476x_core_report_drainer_stop() - mark the completion of the RDS
326  * buffer drain porcess by the worker.
327  *
328  * @core: Core device structure
329  */
330 static inline void si476x_core_report_drainer_stop(struct si476x_core *core)
331 {
332 	mutex_lock(&core->rds_drainer_status_lock);
333 	core->rds_drainer_is_working = false;
334 	mutex_unlock(&core->rds_drainer_status_lock);
335 }
336 
337 /**
338  * si476x_core_start_rds_drainer_once() - start RDS drainer worker if
339  * ther is none working, do nothing otherwise
340  *
341  * @core: Datastructure corresponding to the chip.
342  */
343 static inline void si476x_core_start_rds_drainer_once(struct si476x_core *core)
344 {
345 	mutex_lock(&core->rds_drainer_status_lock);
346 	if (!core->rds_drainer_is_working) {
347 		core->rds_drainer_is_working = true;
348 		schedule_work(&core->rds_fifo_drainer);
349 	}
350 	mutex_unlock(&core->rds_drainer_status_lock);
351 }
352 /**
353  * si476x_core_drain_rds_fifo() - RDS buffer drainer.
354  * @work: struct work_struct being ppassed to the function by the
355  * kernel.
356  *
357  * Drain the contents of the RDS FIFO of
358  */
359 static void si476x_core_drain_rds_fifo(struct work_struct *work)
360 {
361 	int err;
362 
363 	struct si476x_core *core = container_of(work, struct si476x_core,
364 						rds_fifo_drainer);
365 
366 	struct si476x_rds_status_report report;
367 
368 	si476x_core_lock(core);
369 	err = si476x_core_cmd_fm_rds_status(core, true, false, false, &report);
370 	if (!err) {
371 		int i = report.rdsfifoused;
372 		dev_dbg(&core->client->dev,
373 			"%d elements in RDS FIFO. Draining.\n", i);
374 		for (; i > 0; --i) {
375 			err = si476x_core_cmd_fm_rds_status(core, false, false,
376 							    (i == 1), &report);
377 			if (err < 0)
378 				goto unlock;
379 
380 			kfifo_in(&core->rds_fifo, report.rds,
381 				 sizeof(report.rds));
382 			dev_dbg(&core->client->dev, "RDS data:\n %*ph\n",
383 				(int)sizeof(report.rds), report.rds);
384 		}
385 		dev_dbg(&core->client->dev, "Drrrrained!\n");
386 		wake_up_interruptible(&core->rds_read_queue);
387 	}
388 
389 unlock:
390 	si476x_core_unlock(core);
391 	si476x_core_report_drainer_stop(core);
392 }
393 
394 /**
395  * si476x_core_pronounce_dead()
396  *
397  * @core: Core device structure
398  *
399  * Mark the device as being dead and wake up all potentially waiting
400  * threads of execution.
401  *
402  */
403 static void si476x_core_pronounce_dead(struct si476x_core *core)
404 {
405 	dev_info(&core->client->dev, "Core device is dead.\n");
406 
407 	atomic_set(&core->is_alive, 0);
408 
409 	/* Wake up al possible waiting processes */
410 	wake_up_interruptible(&core->rds_read_queue);
411 
412 	atomic_set(&core->cts, 1);
413 	wake_up(&core->command);
414 
415 	atomic_set(&core->stc, 1);
416 	wake_up(&core->tuning);
417 }
418 
419 /**
420  * si476x_core_i2c_xfer()
421  *
422  * @core: Core device structure
423  * @type: Transfer type
424  * @buf: Transfer buffer for/with data
425  * @count: Transfer buffer size
426  *
427  * Perfrom and I2C transfer(either read or write) and keep a counter
428  * of I/O errors. If the error counter rises above the threshold
429  * pronounce device dead.
430  *
431  * The function returns zero on succes or negative error code on
432  * failure.
433  */
434 int si476x_core_i2c_xfer(struct si476x_core *core,
435 		    enum si476x_i2c_type type,
436 		    char *buf, int count)
437 {
438 	static int io_errors_count;
439 	int err;
440 	if (type == SI476X_I2C_SEND)
441 		err = i2c_master_send(core->client, buf, count);
442 	else
443 		err = i2c_master_recv(core->client, buf, count);
444 
445 	if (err < 0) {
446 		if (io_errors_count++ > SI476X_MAX_IO_ERRORS)
447 			si476x_core_pronounce_dead(core);
448 	} else {
449 		io_errors_count = 0;
450 	}
451 
452 	return err;
453 }
454 EXPORT_SYMBOL_GPL(si476x_core_i2c_xfer);
455 
456 /**
457  * si476x_core_get_status()
458  * @core: Core device structure
459  *
460  * Get the status byte of the core device by berforming one byte I2C
461  * read.
462  *
463  * The function returns a status value or a negative error code on
464  * error.
465  */
466 static int si476x_core_get_status(struct si476x_core *core)
467 {
468 	u8 response;
469 	int err = si476x_core_i2c_xfer(core, SI476X_I2C_RECV,
470 				  &response, sizeof(response));
471 
472 	return (err < 0) ? err : response;
473 }
474 
475 /**
476  * si476x_core_get_and_signal_status() - IRQ dispatcher
477  * @core: Core device structure
478  *
479  * Dispatch the arrived interrupt request based on the value of the
480  * status byte reported by the tuner.
481  *
482  */
483 static void si476x_core_get_and_signal_status(struct si476x_core *core)
484 {
485 	int status = si476x_core_get_status(core);
486 	if (status < 0) {
487 		dev_err(&core->client->dev, "Failed to get status\n");
488 		return;
489 	}
490 
491 	if (status & SI476X_CTS) {
492 		/* Unfortunately completions could not be used for
493 		 * signalling CTS since this flag cannot be cleared
494 		 * in status byte, and therefore once it becomes true
495 		 * multiple calls to 'complete' would cause the
496 		 * commands following the current one to be completed
497 		 * before they actually are */
498 		dev_dbg(&core->client->dev, "[interrupt] CTSINT\n");
499 		atomic_set(&core->cts, 1);
500 		wake_up(&core->command);
501 	}
502 
503 	if (status & SI476X_FM_RDS_INT) {
504 		dev_dbg(&core->client->dev, "[interrupt] RDSINT\n");
505 		si476x_core_start_rds_drainer_once(core);
506 	}
507 
508 	if (status & SI476X_STC_INT) {
509 		dev_dbg(&core->client->dev, "[interrupt] STCINT\n");
510 		atomic_set(&core->stc, 1);
511 		wake_up(&core->tuning);
512 	}
513 }
514 
515 static void si476x_core_poll_loop(struct work_struct *work)
516 {
517 	struct si476x_core *core = SI476X_WORK_TO_CORE(work);
518 
519 	si476x_core_get_and_signal_status(core);
520 
521 	if (atomic_read(&core->is_alive))
522 		si476x_core_schedule_polling_work(core);
523 }
524 
525 static irqreturn_t si476x_core_interrupt(int irq, void *dev)
526 {
527 	struct si476x_core *core = dev;
528 
529 	si476x_core_get_and_signal_status(core);
530 
531 	return IRQ_HANDLED;
532 }
533 
534 /**
535  * si476x_core_fwver_to_revision()
536  * @core: Core device structure
537  * @func: Selects the boot function of the device:
538  *         *_BOOTLOADER  - Boot loader
539  *         *_FM_RECEIVER - FM receiver
540  *         *_AM_RECEIVER - AM receiver
541  *         *_WB_RECEIVER - Weatherband receiver
542  * @major:  Firmware major number
543  * @minor1: Firmware first minor number
544  * @minor2: Firmware second minor number
545  *
546  * Convert a chip's firmware version number into an offset that later
547  * will be used to as offset in "vtable" of tuner functions
548  *
549  * This function returns a positive offset in case of success and a -1
550  * in case of failure.
551  */
552 static int si476x_core_fwver_to_revision(struct si476x_core *core,
553 					 int func, int major,
554 					 int minor1, int minor2)
555 {
556 	switch (func) {
557 	case SI476X_FUNC_FM_RECEIVER:
558 		switch (major) {
559 		case 5:
560 			return SI476X_REVISION_A10;
561 		case 8:
562 			return SI476X_REVISION_A20;
563 		case 10:
564 			return SI476X_REVISION_A30;
565 		default:
566 			goto unknown_revision;
567 		}
568 	case SI476X_FUNC_AM_RECEIVER:
569 		switch (major) {
570 		case 5:
571 			return SI476X_REVISION_A10;
572 		case 7:
573 			return SI476X_REVISION_A20;
574 		case 9:
575 			return SI476X_REVISION_A30;
576 		default:
577 			goto unknown_revision;
578 		}
579 	case SI476X_FUNC_WB_RECEIVER:
580 		switch (major) {
581 		case 3:
582 			return SI476X_REVISION_A10;
583 		case 5:
584 			return SI476X_REVISION_A20;
585 		case 7:
586 			return SI476X_REVISION_A30;
587 		default:
588 			goto unknown_revision;
589 		}
590 	case SI476X_FUNC_BOOTLOADER:
591 	default:		/* FALLTHROUGH */
592 		BUG();
593 		return -1;
594 	}
595 
596 unknown_revision:
597 	dev_err(&core->client->dev,
598 		"Unsupported version of the firmware: %d.%d.%d, "
599 		"reverting to A10 compatible functions\n",
600 		major, minor1, minor2);
601 
602 	return SI476X_REVISION_A10;
603 }
604 
605 /**
606  * si476x_core_get_revision_info()
607  * @core: Core device structure
608  *
609  * Get the firmware version number of the device. It is done in
610  * following three steps:
611  *    1. Power-up the device
612  *    2. Send the 'FUNC_INFO' command
613  *    3. Powering the device down.
614  *
615  * The function return zero on success and a negative error code on
616  * failure.
617  */
618 static int si476x_core_get_revision_info(struct si476x_core *core)
619 {
620 	int rval;
621 	struct si476x_func_info info;
622 
623 	si476x_core_lock(core);
624 	rval = si476x_core_set_power_state(core, SI476X_POWER_UP_FULL);
625 	if (rval < 0)
626 		goto exit;
627 
628 	rval = si476x_core_cmd_func_info(core, &info);
629 	if (rval < 0)
630 		goto power_down;
631 
632 	core->revision = si476x_core_fwver_to_revision(core, info.func,
633 						       info.firmware.major,
634 						       info.firmware.minor[0],
635 						       info.firmware.minor[1]);
636 power_down:
637 	si476x_core_set_power_state(core, SI476X_POWER_DOWN);
638 exit:
639 	si476x_core_unlock(core);
640 
641 	return rval;
642 }
643 
644 bool si476x_core_has_am(struct si476x_core *core)
645 {
646 	return core->chip_id == SI476X_CHIP_SI4761 ||
647 		core->chip_id == SI476X_CHIP_SI4764;
648 }
649 EXPORT_SYMBOL_GPL(si476x_core_has_am);
650 
651 bool si476x_core_has_diversity(struct si476x_core *core)
652 {
653 	return core->chip_id == SI476X_CHIP_SI4764;
654 }
655 EXPORT_SYMBOL_GPL(si476x_core_has_diversity);
656 
657 bool si476x_core_is_a_secondary_tuner(struct si476x_core *core)
658 {
659 	return si476x_core_has_diversity(core) &&
660 		(core->diversity_mode == SI476X_PHDIV_SECONDARY_ANTENNA ||
661 		 core->diversity_mode == SI476X_PHDIV_SECONDARY_COMBINING);
662 }
663 EXPORT_SYMBOL_GPL(si476x_core_is_a_secondary_tuner);
664 
665 bool si476x_core_is_a_primary_tuner(struct si476x_core *core)
666 {
667 	return si476x_core_has_diversity(core) &&
668 		(core->diversity_mode == SI476X_PHDIV_PRIMARY_ANTENNA ||
669 		 core->diversity_mode == SI476X_PHDIV_PRIMARY_COMBINING);
670 }
671 EXPORT_SYMBOL_GPL(si476x_core_is_a_primary_tuner);
672 
673 bool si476x_core_is_in_am_receiver_mode(struct si476x_core *core)
674 {
675 	return si476x_core_has_am(core) &&
676 		(core->power_up_parameters.func == SI476X_FUNC_AM_RECEIVER);
677 }
678 EXPORT_SYMBOL_GPL(si476x_core_is_in_am_receiver_mode);
679 
680 bool si476x_core_is_powered_up(struct si476x_core *core)
681 {
682 	return core->power_state == SI476X_POWER_UP_FULL;
683 }
684 EXPORT_SYMBOL_GPL(si476x_core_is_powered_up);
685 
686 static int si476x_core_probe(struct i2c_client *client)
687 {
688 	const struct i2c_device_id *id = i2c_client_get_device_id(client);
689 	int rval;
690 	struct si476x_core          *core;
691 	struct si476x_platform_data *pdata;
692 	struct mfd_cell *cell;
693 	int              cell_num;
694 
695 	core = devm_kzalloc(&client->dev, sizeof(*core), GFP_KERNEL);
696 	if (!core)
697 		return -ENOMEM;
698 
699 	core->client = client;
700 
701 	core->regmap = devm_regmap_init_si476x(core);
702 	if (IS_ERR(core->regmap)) {
703 		rval = PTR_ERR(core->regmap);
704 		dev_err(&client->dev,
705 			"Failed to allocate register map: %d\n",
706 			rval);
707 		return rval;
708 	}
709 
710 	i2c_set_clientdata(client, core);
711 
712 	atomic_set(&core->is_alive, 0);
713 	core->power_state = SI476X_POWER_DOWN;
714 
715 	pdata = dev_get_platdata(&client->dev);
716 	if (pdata) {
717 		memcpy(&core->power_up_parameters,
718 		       &pdata->power_up_parameters,
719 		       sizeof(core->power_up_parameters));
720 
721 		core->gpio_reset = -1;
722 		if (gpio_is_valid(pdata->gpio_reset)) {
723 			rval = gpio_request(pdata->gpio_reset, "si476x reset");
724 			if (rval) {
725 				dev_err(&client->dev,
726 					"Failed to request gpio: %d\n", rval);
727 				return rval;
728 			}
729 			core->gpio_reset = pdata->gpio_reset;
730 			gpio_direction_output(core->gpio_reset, 0);
731 		}
732 
733 		core->diversity_mode = pdata->diversity_mode;
734 		memcpy(&core->pinmux, &pdata->pinmux,
735 		       sizeof(struct si476x_pinmux));
736 	} else {
737 		dev_err(&client->dev, "No platform data provided\n");
738 		return -EINVAL;
739 	}
740 
741 	core->supplies[0].supply = "vd";
742 	core->supplies[1].supply = "va";
743 	core->supplies[2].supply = "vio1";
744 	core->supplies[3].supply = "vio2";
745 
746 	rval = devm_regulator_bulk_get(&client->dev,
747 				       ARRAY_SIZE(core->supplies),
748 				       core->supplies);
749 	if (rval) {
750 		dev_err(&client->dev, "Failed to get all of the regulators\n");
751 		goto free_gpio;
752 	}
753 
754 	mutex_init(&core->cmd_lock);
755 	init_waitqueue_head(&core->command);
756 	init_waitqueue_head(&core->tuning);
757 
758 	rval = kfifo_alloc(&core->rds_fifo,
759 			   SI476X_DRIVER_RDS_FIFO_DEPTH *
760 			   sizeof(struct v4l2_rds_data),
761 			   GFP_KERNEL);
762 	if (rval) {
763 		dev_err(&client->dev, "Could not allocate the FIFO\n");
764 		goto free_gpio;
765 	}
766 	mutex_init(&core->rds_drainer_status_lock);
767 	init_waitqueue_head(&core->rds_read_queue);
768 	INIT_WORK(&core->rds_fifo_drainer, si476x_core_drain_rds_fifo);
769 
770 	if (client->irq) {
771 		rval = devm_request_threaded_irq(&client->dev,
772 						 client->irq, NULL,
773 						 si476x_core_interrupt,
774 						 IRQF_TRIGGER_FALLING |
775 						 IRQF_ONESHOT,
776 						 client->name, core);
777 		if (rval < 0) {
778 			dev_err(&client->dev, "Could not request IRQ %d\n",
779 				client->irq);
780 			goto free_kfifo;
781 		}
782 		disable_irq(client->irq);
783 		dev_dbg(&client->dev, "IRQ requested.\n");
784 
785 		core->rds_fifo_depth = 20;
786 	} else {
787 		INIT_DELAYED_WORK(&core->status_monitor,
788 				  si476x_core_poll_loop);
789 		dev_info(&client->dev,
790 			 "No IRQ number specified, will use polling\n");
791 
792 		core->rds_fifo_depth = 5;
793 	}
794 
795 	core->chip_id = id->driver_data;
796 
797 	rval = si476x_core_get_revision_info(core);
798 	if (rval < 0) {
799 		rval = -ENODEV;
800 		goto free_kfifo;
801 	}
802 
803 	cell_num = 0;
804 
805 	cell = &core->cells[SI476X_RADIO_CELL];
806 	cell->name = "si476x-radio";
807 	cell_num++;
808 
809 #ifdef CONFIG_SND_SOC_SI476X
810 	if ((core->chip_id == SI476X_CHIP_SI4761 ||
811 	     core->chip_id == SI476X_CHIP_SI4764)	&&
812 	    core->pinmux.dclk == SI476X_DCLK_DAUDIO     &&
813 	    core->pinmux.dfs  == SI476X_DFS_DAUDIO      &&
814 	    core->pinmux.dout == SI476X_DOUT_I2S_OUTPUT &&
815 	    core->pinmux.xout == SI476X_XOUT_TRISTATE) {
816 		cell = &core->cells[SI476X_CODEC_CELL];
817 		cell->name          = "si476x-codec";
818 		cell_num++;
819 	}
820 #endif
821 	rval = mfd_add_devices(&client->dev,
822 			       (client->adapter->nr << 8) + client->addr,
823 			       core->cells, cell_num,
824 			       NULL, 0, NULL);
825 	if (!rval)
826 		return 0;
827 
828 free_kfifo:
829 	kfifo_free(&core->rds_fifo);
830 
831 free_gpio:
832 	if (gpio_is_valid(core->gpio_reset))
833 		gpio_free(core->gpio_reset);
834 
835 	return rval;
836 }
837 
838 static void si476x_core_remove(struct i2c_client *client)
839 {
840 	struct si476x_core *core = i2c_get_clientdata(client);
841 
842 	si476x_core_pronounce_dead(core);
843 	mfd_remove_devices(&client->dev);
844 
845 	if (client->irq)
846 		disable_irq(client->irq);
847 	else
848 		cancel_delayed_work_sync(&core->status_monitor);
849 
850 	kfifo_free(&core->rds_fifo);
851 
852 	if (gpio_is_valid(core->gpio_reset))
853 		gpio_free(core->gpio_reset);
854 }
855 
856 
857 static const struct i2c_device_id si476x_id[] = {
858 	{ "si4761", SI476X_CHIP_SI4761 },
859 	{ "si4764", SI476X_CHIP_SI4764 },
860 	{ "si4768", SI476X_CHIP_SI4768 },
861 	{ },
862 };
863 MODULE_DEVICE_TABLE(i2c, si476x_id);
864 
865 static struct i2c_driver si476x_core_driver = {
866 	.driver		= {
867 		.name	= "si476x-core",
868 	},
869 	.probe_new	= si476x_core_probe,
870 	.remove         = si476x_core_remove,
871 	.id_table       = si476x_id,
872 };
873 module_i2c_driver(si476x_core_driver);
874 
875 
876 MODULE_AUTHOR("Andrey Smirnov <andrew.smirnov@gmail.com>");
877 MODULE_DESCRIPTION("Si4761/64/68 AM/FM MFD core device driver");
878 MODULE_LICENSE("GPL");
879