xref: /linux/drivers/mfd/ucb1x00-core.c (revision 3f60db4bde17088feed5f143582d7661cdbb9a01)
1 /*
2  *  linux/drivers/mfd/ucb1x00-core.c
3  *
4  *  Copyright (C) 2001 Russell King, All Rights Reserved.
5  *
6  * This program is free software; you can redistribute it and/or modify
7  * it under the terms of the GNU General Public License as published by
8  * the Free Software Foundation; either version 2 of the License.
9  *
10  *  The UCB1x00 core driver provides basic services for handling IO,
11  *  the ADC, interrupts, and accessing registers.  It is designed
12  *  such that everything goes through this layer, thereby providing
13  *  a consistent locking methodology, as well as allowing the drivers
14  *  to be used on other non-MCP-enabled hardware platforms.
15  *
16  *  Note that all locks are private to this file.  Nothing else may
17  *  touch them.
18  */
19 #include <linux/module.h>
20 #include <linux/kernel.h>
21 #include <linux/sched.h>
22 #include <linux/slab.h>
23 #include <linux/init.h>
24 #include <linux/errno.h>
25 #include <linux/interrupt.h>
26 #include <linux/device.h>
27 #include <linux/mutex.h>
28 #include <linux/mfd/ucb1x00.h>
29 #include <linux/gpio.h>
30 #include <linux/semaphore.h>
31 
32 #include <mach/dma.h>
33 #include <mach/hardware.h>
34 
35 static DEFINE_MUTEX(ucb1x00_mutex);
36 static LIST_HEAD(ucb1x00_drivers);
37 static LIST_HEAD(ucb1x00_devices);
38 
39 /**
40  *	ucb1x00_io_set_dir - set IO direction
41  *	@ucb: UCB1x00 structure describing chip
42  *	@in:  bitfield of IO pins to be set as inputs
43  *	@out: bitfield of IO pins to be set as outputs
44  *
45  *	Set the IO direction of the ten general purpose IO pins on
46  *	the UCB1x00 chip.  The @in bitfield has priority over the
47  *	@out bitfield, in that if you specify a pin as both input
48  *	and output, it will end up as an input.
49  *
50  *	ucb1x00_enable must have been called to enable the comms
51  *	before using this function.
52  *
53  *	This function takes a spinlock, disabling interrupts.
54  */
55 void ucb1x00_io_set_dir(struct ucb1x00 *ucb, unsigned int in, unsigned int out)
56 {
57 	unsigned long flags;
58 
59 	spin_lock_irqsave(&ucb->io_lock, flags);
60 	ucb->io_dir |= out;
61 	ucb->io_dir &= ~in;
62 
63 	ucb1x00_reg_write(ucb, UCB_IO_DIR, ucb->io_dir);
64 	spin_unlock_irqrestore(&ucb->io_lock, flags);
65 }
66 
67 /**
68  *	ucb1x00_io_write - set or clear IO outputs
69  *	@ucb:   UCB1x00 structure describing chip
70  *	@set:   bitfield of IO pins to set to logic '1'
71  *	@clear: bitfield of IO pins to set to logic '0'
72  *
73  *	Set the IO output state of the specified IO pins.  The value
74  *	is retained if the pins are subsequently configured as inputs.
75  *	The @clear bitfield has priority over the @set bitfield -
76  *	outputs will be cleared.
77  *
78  *	ucb1x00_enable must have been called to enable the comms
79  *	before using this function.
80  *
81  *	This function takes a spinlock, disabling interrupts.
82  */
83 void ucb1x00_io_write(struct ucb1x00 *ucb, unsigned int set, unsigned int clear)
84 {
85 	unsigned long flags;
86 
87 	spin_lock_irqsave(&ucb->io_lock, flags);
88 	ucb->io_out |= set;
89 	ucb->io_out &= ~clear;
90 
91 	ucb1x00_reg_write(ucb, UCB_IO_DATA, ucb->io_out);
92 	spin_unlock_irqrestore(&ucb->io_lock, flags);
93 }
94 
95 /**
96  *	ucb1x00_io_read - read the current state of the IO pins
97  *	@ucb: UCB1x00 structure describing chip
98  *
99  *	Return a bitfield describing the logic state of the ten
100  *	general purpose IO pins.
101  *
102  *	ucb1x00_enable must have been called to enable the comms
103  *	before using this function.
104  *
105  *	This function does not take any semaphores or spinlocks.
106  */
107 unsigned int ucb1x00_io_read(struct ucb1x00 *ucb)
108 {
109 	return ucb1x00_reg_read(ucb, UCB_IO_DATA);
110 }
111 
112 static void ucb1x00_gpio_set(struct gpio_chip *chip, unsigned offset, int value)
113 {
114 	struct ucb1x00 *ucb = container_of(chip, struct ucb1x00, gpio);
115 	unsigned long flags;
116 
117 	spin_lock_irqsave(&ucb->io_lock, flags);
118 	if (value)
119 		ucb->io_out |= 1 << offset;
120 	else
121 		ucb->io_out &= ~(1 << offset);
122 
123 	ucb1x00_reg_write(ucb, UCB_IO_DATA, ucb->io_out);
124 	spin_unlock_irqrestore(&ucb->io_lock, flags);
125 }
126 
127 static int ucb1x00_gpio_get(struct gpio_chip *chip, unsigned offset)
128 {
129 	struct ucb1x00 *ucb = container_of(chip, struct ucb1x00, gpio);
130 	return ucb1x00_reg_read(ucb, UCB_IO_DATA) & (1 << offset);
131 }
132 
133 static int ucb1x00_gpio_direction_input(struct gpio_chip *chip, unsigned offset)
134 {
135 	struct ucb1x00 *ucb = container_of(chip, struct ucb1x00, gpio);
136 	unsigned long flags;
137 
138 	spin_lock_irqsave(&ucb->io_lock, flags);
139 	ucb->io_dir &= ~(1 << offset);
140 	ucb1x00_reg_write(ucb, UCB_IO_DIR, ucb->io_dir);
141 	spin_unlock_irqrestore(&ucb->io_lock, flags);
142 
143 	return 0;
144 }
145 
146 static int ucb1x00_gpio_direction_output(struct gpio_chip *chip, unsigned offset
147 		, int value)
148 {
149 	struct ucb1x00 *ucb = container_of(chip, struct ucb1x00, gpio);
150 	unsigned long flags;
151 	unsigned old, mask = 1 << offset;
152 
153 	spin_lock_irqsave(&ucb->io_lock, flags);
154 	old = ucb->io_out;
155 	if (value)
156 		ucb->io_out |= mask;
157 	else
158 		ucb->io_out &= ~mask;
159 
160 	if (old != ucb->io_out)
161 		ucb1x00_reg_write(ucb, UCB_IO_DATA, ucb->io_out);
162 
163 	if (!(ucb->io_dir & mask)) {
164 		ucb->io_dir |= mask;
165 		ucb1x00_reg_write(ucb, UCB_IO_DIR, ucb->io_dir);
166 	}
167 	spin_unlock_irqrestore(&ucb->io_lock, flags);
168 
169 	return 0;
170 }
171 
172 /*
173  * UCB1300 data sheet says we must:
174  *  1. enable ADC	=> 5us (including reference startup time)
175  *  2. select input	=> 51*tsibclk  => 4.3us
176  *  3. start conversion	=> 102*tsibclk => 8.5us
177  * (tsibclk = 1/11981000)
178  * Period between SIB 128-bit frames = 10.7us
179  */
180 
181 /**
182  *	ucb1x00_adc_enable - enable the ADC converter
183  *	@ucb: UCB1x00 structure describing chip
184  *
185  *	Enable the ucb1x00 and ADC converter on the UCB1x00 for use.
186  *	Any code wishing to use the ADC converter must call this
187  *	function prior to using it.
188  *
189  *	This function takes the ADC semaphore to prevent two or more
190  *	concurrent uses, and therefore may sleep.  As a result, it
191  *	can only be called from process context, not interrupt
192  *	context.
193  *
194  *	You should release the ADC as soon as possible using
195  *	ucb1x00_adc_disable.
196  */
197 void ucb1x00_adc_enable(struct ucb1x00 *ucb)
198 {
199 	down(&ucb->adc_sem);
200 
201 	ucb->adc_cr |= UCB_ADC_ENA;
202 
203 	ucb1x00_enable(ucb);
204 	ucb1x00_reg_write(ucb, UCB_ADC_CR, ucb->adc_cr);
205 }
206 
207 /**
208  *	ucb1x00_adc_read - read the specified ADC channel
209  *	@ucb: UCB1x00 structure describing chip
210  *	@adc_channel: ADC channel mask
211  *	@sync: wait for syncronisation pulse.
212  *
213  *	Start an ADC conversion and wait for the result.  Note that
214  *	synchronised ADC conversions (via the ADCSYNC pin) must wait
215  *	until the trigger is asserted and the conversion is finished.
216  *
217  *	This function currently spins waiting for the conversion to
218  *	complete (2 frames max without sync).
219  *
220  *	If called for a synchronised ADC conversion, it may sleep
221  *	with the ADC semaphore held.
222  */
223 unsigned int ucb1x00_adc_read(struct ucb1x00 *ucb, int adc_channel, int sync)
224 {
225 	unsigned int val;
226 
227 	if (sync)
228 		adc_channel |= UCB_ADC_SYNC_ENA;
229 
230 	ucb1x00_reg_write(ucb, UCB_ADC_CR, ucb->adc_cr | adc_channel);
231 	ucb1x00_reg_write(ucb, UCB_ADC_CR, ucb->adc_cr | adc_channel | UCB_ADC_START);
232 
233 	for (;;) {
234 		val = ucb1x00_reg_read(ucb, UCB_ADC_DATA);
235 		if (val & UCB_ADC_DAT_VAL)
236 			break;
237 		/* yield to other processes */
238 		set_current_state(TASK_INTERRUPTIBLE);
239 		schedule_timeout(1);
240 	}
241 
242 	return UCB_ADC_DAT(val);
243 }
244 
245 /**
246  *	ucb1x00_adc_disable - disable the ADC converter
247  *	@ucb: UCB1x00 structure describing chip
248  *
249  *	Disable the ADC converter and release the ADC semaphore.
250  */
251 void ucb1x00_adc_disable(struct ucb1x00 *ucb)
252 {
253 	ucb->adc_cr &= ~UCB_ADC_ENA;
254 	ucb1x00_reg_write(ucb, UCB_ADC_CR, ucb->adc_cr);
255 	ucb1x00_disable(ucb);
256 
257 	up(&ucb->adc_sem);
258 }
259 
260 /*
261  * UCB1x00 Interrupt handling.
262  *
263  * The UCB1x00 can generate interrupts when the SIBCLK is stopped.
264  * Since we need to read an internal register, we must re-enable
265  * SIBCLK to talk to the chip.  We leave the clock running until
266  * we have finished processing all interrupts from the chip.
267  */
268 static irqreturn_t ucb1x00_irq(int irqnr, void *devid)
269 {
270 	struct ucb1x00 *ucb = devid;
271 	struct ucb1x00_irq *irq;
272 	unsigned int isr, i;
273 
274 	ucb1x00_enable(ucb);
275 	isr = ucb1x00_reg_read(ucb, UCB_IE_STATUS);
276 	ucb1x00_reg_write(ucb, UCB_IE_CLEAR, isr);
277 	ucb1x00_reg_write(ucb, UCB_IE_CLEAR, 0);
278 
279 	for (i = 0, irq = ucb->irq_handler; i < 16 && isr; i++, isr >>= 1, irq++)
280 		if (isr & 1 && irq->fn)
281 			irq->fn(i, irq->devid);
282 	ucb1x00_disable(ucb);
283 
284 	return IRQ_HANDLED;
285 }
286 
287 /**
288  *	ucb1x00_hook_irq - hook a UCB1x00 interrupt
289  *	@ucb:   UCB1x00 structure describing chip
290  *	@idx:   interrupt index
291  *	@fn:    function to call when interrupt is triggered
292  *	@devid: device id to pass to interrupt handler
293  *
294  *	Hook the specified interrupt.  You can only register one handler
295  *	for each interrupt source.  The interrupt source is not enabled
296  *	by this function; use ucb1x00_enable_irq instead.
297  *
298  *	Interrupt handlers will be called with other interrupts enabled.
299  *
300  *	Returns zero on success, or one of the following errors:
301  *	 -EINVAL if the interrupt index is invalid
302  *	 -EBUSY if the interrupt has already been hooked
303  */
304 int ucb1x00_hook_irq(struct ucb1x00 *ucb, unsigned int idx, void (*fn)(int, void *), void *devid)
305 {
306 	struct ucb1x00_irq *irq;
307 	int ret = -EINVAL;
308 
309 	if (idx < 16) {
310 		irq = ucb->irq_handler + idx;
311 		ret = -EBUSY;
312 
313 		spin_lock_irq(&ucb->lock);
314 		if (irq->fn == NULL) {
315 			irq->devid = devid;
316 			irq->fn = fn;
317 			ret = 0;
318 		}
319 		spin_unlock_irq(&ucb->lock);
320 	}
321 	return ret;
322 }
323 
324 /**
325  *	ucb1x00_enable_irq - enable an UCB1x00 interrupt source
326  *	@ucb: UCB1x00 structure describing chip
327  *	@idx: interrupt index
328  *	@edges: interrupt edges to enable
329  *
330  *	Enable the specified interrupt to trigger on %UCB_RISING,
331  *	%UCB_FALLING or both edges.  The interrupt should have been
332  *	hooked by ucb1x00_hook_irq.
333  */
334 void ucb1x00_enable_irq(struct ucb1x00 *ucb, unsigned int idx, int edges)
335 {
336 	unsigned long flags;
337 
338 	if (idx < 16) {
339 		spin_lock_irqsave(&ucb->lock, flags);
340 
341 		ucb1x00_enable(ucb);
342 		if (edges & UCB_RISING) {
343 			ucb->irq_ris_enbl |= 1 << idx;
344 			ucb1x00_reg_write(ucb, UCB_IE_RIS, ucb->irq_ris_enbl);
345 		}
346 		if (edges & UCB_FALLING) {
347 			ucb->irq_fal_enbl |= 1 << idx;
348 			ucb1x00_reg_write(ucb, UCB_IE_FAL, ucb->irq_fal_enbl);
349 		}
350 		ucb1x00_disable(ucb);
351 		spin_unlock_irqrestore(&ucb->lock, flags);
352 	}
353 }
354 
355 /**
356  *	ucb1x00_disable_irq - disable an UCB1x00 interrupt source
357  *	@ucb: UCB1x00 structure describing chip
358  *	@edges: interrupt edges to disable
359  *
360  *	Disable the specified interrupt triggering on the specified
361  *	(%UCB_RISING, %UCB_FALLING or both) edges.
362  */
363 void ucb1x00_disable_irq(struct ucb1x00 *ucb, unsigned int idx, int edges)
364 {
365 	unsigned long flags;
366 
367 	if (idx < 16) {
368 		spin_lock_irqsave(&ucb->lock, flags);
369 
370 		ucb1x00_enable(ucb);
371 		if (edges & UCB_RISING) {
372 			ucb->irq_ris_enbl &= ~(1 << idx);
373 			ucb1x00_reg_write(ucb, UCB_IE_RIS, ucb->irq_ris_enbl);
374 		}
375 		if (edges & UCB_FALLING) {
376 			ucb->irq_fal_enbl &= ~(1 << idx);
377 			ucb1x00_reg_write(ucb, UCB_IE_FAL, ucb->irq_fal_enbl);
378 		}
379 		ucb1x00_disable(ucb);
380 		spin_unlock_irqrestore(&ucb->lock, flags);
381 	}
382 }
383 
384 /**
385  *	ucb1x00_free_irq - disable and free the specified UCB1x00 interrupt
386  *	@ucb: UCB1x00 structure describing chip
387  *	@idx: interrupt index
388  *	@devid: device id.
389  *
390  *	Disable the interrupt source and remove the handler.  devid must
391  *	match the devid passed when hooking the interrupt.
392  *
393  *	Returns zero on success, or one of the following errors:
394  *	 -EINVAL if the interrupt index is invalid
395  *	 -ENOENT if devid does not match
396  */
397 int ucb1x00_free_irq(struct ucb1x00 *ucb, unsigned int idx, void *devid)
398 {
399 	struct ucb1x00_irq *irq;
400 	int ret;
401 
402 	if (idx >= 16)
403 		goto bad;
404 
405 	irq = ucb->irq_handler + idx;
406 	ret = -ENOENT;
407 
408 	spin_lock_irq(&ucb->lock);
409 	if (irq->devid == devid) {
410 		ucb->irq_ris_enbl &= ~(1 << idx);
411 		ucb->irq_fal_enbl &= ~(1 << idx);
412 
413 		ucb1x00_enable(ucb);
414 		ucb1x00_reg_write(ucb, UCB_IE_RIS, ucb->irq_ris_enbl);
415 		ucb1x00_reg_write(ucb, UCB_IE_FAL, ucb->irq_fal_enbl);
416 		ucb1x00_disable(ucb);
417 
418 		irq->fn = NULL;
419 		irq->devid = NULL;
420 		ret = 0;
421 	}
422 	spin_unlock_irq(&ucb->lock);
423 	return ret;
424 
425 bad:
426 	printk(KERN_ERR "Freeing bad UCB1x00 irq %d\n", idx);
427 	return -EINVAL;
428 }
429 
430 static int ucb1x00_add_dev(struct ucb1x00 *ucb, struct ucb1x00_driver *drv)
431 {
432 	struct ucb1x00_dev *dev;
433 	int ret = -ENOMEM;
434 
435 	dev = kmalloc(sizeof(struct ucb1x00_dev), GFP_KERNEL);
436 	if (dev) {
437 		dev->ucb = ucb;
438 		dev->drv = drv;
439 
440 		ret = drv->add(dev);
441 
442 		if (ret == 0) {
443 			list_add(&dev->dev_node, &ucb->devs);
444 			list_add(&dev->drv_node, &drv->devs);
445 		} else {
446 			kfree(dev);
447 		}
448 	}
449 	return ret;
450 }
451 
452 static void ucb1x00_remove_dev(struct ucb1x00_dev *dev)
453 {
454 	dev->drv->remove(dev);
455 	list_del(&dev->dev_node);
456 	list_del(&dev->drv_node);
457 	kfree(dev);
458 }
459 
460 /*
461  * Try to probe our interrupt, rather than relying on lots of
462  * hard-coded machine dependencies.  For reference, the expected
463  * IRQ mappings are:
464  *
465  *  	Machine		Default IRQ
466  *	adsbitsy	IRQ_GPCIN4
467  *	cerf		IRQ_GPIO_UCB1200_IRQ
468  *	flexanet	IRQ_GPIO_GUI
469  *	freebird	IRQ_GPIO_FREEBIRD_UCB1300_IRQ
470  *	graphicsclient	ADS_EXT_IRQ(8)
471  *	graphicsmaster	ADS_EXT_IRQ(8)
472  *	lart		LART_IRQ_UCB1200
473  *	omnimeter	IRQ_GPIO23
474  *	pfs168		IRQ_GPIO_UCB1300_IRQ
475  *	simpad		IRQ_GPIO_UCB1300_IRQ
476  *	shannon		SHANNON_IRQ_GPIO_IRQ_CODEC
477  *	yopy		IRQ_GPIO_UCB1200_IRQ
478  */
479 static int ucb1x00_detect_irq(struct ucb1x00 *ucb)
480 {
481 	unsigned long mask;
482 
483 	mask = probe_irq_on();
484 	if (!mask) {
485 		probe_irq_off(mask);
486 		return NO_IRQ;
487 	}
488 
489 	/*
490 	 * Enable the ADC interrupt.
491 	 */
492 	ucb1x00_reg_write(ucb, UCB_IE_RIS, UCB_IE_ADC);
493 	ucb1x00_reg_write(ucb, UCB_IE_FAL, UCB_IE_ADC);
494 	ucb1x00_reg_write(ucb, UCB_IE_CLEAR, 0xffff);
495 	ucb1x00_reg_write(ucb, UCB_IE_CLEAR, 0);
496 
497 	/*
498 	 * Cause an ADC interrupt.
499 	 */
500 	ucb1x00_reg_write(ucb, UCB_ADC_CR, UCB_ADC_ENA);
501 	ucb1x00_reg_write(ucb, UCB_ADC_CR, UCB_ADC_ENA | UCB_ADC_START);
502 
503 	/*
504 	 * Wait for the conversion to complete.
505 	 */
506 	while ((ucb1x00_reg_read(ucb, UCB_ADC_DATA) & UCB_ADC_DAT_VAL) == 0);
507 	ucb1x00_reg_write(ucb, UCB_ADC_CR, 0);
508 
509 	/*
510 	 * Disable and clear interrupt.
511 	 */
512 	ucb1x00_reg_write(ucb, UCB_IE_RIS, 0);
513 	ucb1x00_reg_write(ucb, UCB_IE_FAL, 0);
514 	ucb1x00_reg_write(ucb, UCB_IE_CLEAR, 0xffff);
515 	ucb1x00_reg_write(ucb, UCB_IE_CLEAR, 0);
516 
517 	/*
518 	 * Read triggered interrupt.
519 	 */
520 	return probe_irq_off(mask);
521 }
522 
523 static void ucb1x00_release(struct device *dev)
524 {
525 	struct ucb1x00 *ucb = classdev_to_ucb1x00(dev);
526 	kfree(ucb);
527 }
528 
529 static struct class ucb1x00_class = {
530 	.name		= "ucb1x00",
531 	.dev_release	= ucb1x00_release,
532 };
533 
534 static int ucb1x00_probe(struct mcp *mcp)
535 {
536 	struct ucb1x00 *ucb;
537 	struct ucb1x00_driver *drv;
538 	unsigned int id;
539 	int ret = -ENODEV;
540 	int temp;
541 
542 	mcp_enable(mcp);
543 	id = mcp_reg_read(mcp, UCB_ID);
544 
545 	if (id != UCB_ID_1200 && id != UCB_ID_1300 && id != UCB_ID_TC35143) {
546 		printk(KERN_WARNING "UCB1x00 ID not found: %04x\n", id);
547 		goto err_disable;
548 	}
549 
550 	ucb = kzalloc(sizeof(struct ucb1x00), GFP_KERNEL);
551 	ret = -ENOMEM;
552 	if (!ucb)
553 		goto err_disable;
554 
555 
556 	ucb->dev.class = &ucb1x00_class;
557 	ucb->dev.parent = &mcp->attached_device;
558 	dev_set_name(&ucb->dev, "ucb1x00");
559 
560 	spin_lock_init(&ucb->lock);
561 	spin_lock_init(&ucb->io_lock);
562 	sema_init(&ucb->adc_sem, 1);
563 
564 	ucb->id  = id;
565 	ucb->mcp = mcp;
566 	ucb->irq = ucb1x00_detect_irq(ucb);
567 	if (ucb->irq == NO_IRQ) {
568 		printk(KERN_ERR "UCB1x00: IRQ probe failed\n");
569 		ret = -ENODEV;
570 		goto err_free;
571 	}
572 
573 	ucb->gpio.base = -1;
574 	if (mcp->gpio_base != 0) {
575 		ucb->gpio.label = dev_name(&ucb->dev);
576 		ucb->gpio.base = mcp->gpio_base;
577 		ucb->gpio.ngpio = 10;
578 		ucb->gpio.set = ucb1x00_gpio_set;
579 		ucb->gpio.get = ucb1x00_gpio_get;
580 		ucb->gpio.direction_input = ucb1x00_gpio_direction_input;
581 		ucb->gpio.direction_output = ucb1x00_gpio_direction_output;
582 		ret = gpiochip_add(&ucb->gpio);
583 		if (ret)
584 			goto err_free;
585 	} else
586 		dev_info(&ucb->dev, "gpio_base not set so no gpiolib support");
587 
588 	ret = request_irq(ucb->irq, ucb1x00_irq, IRQF_TRIGGER_RISING,
589 			  "UCB1x00", ucb);
590 	if (ret) {
591 		printk(KERN_ERR "ucb1x00: unable to grab irq%d: %d\n",
592 			ucb->irq, ret);
593 		goto err_gpio;
594 	}
595 
596 	mcp_set_drvdata(mcp, ucb);
597 
598 	ret = device_register(&ucb->dev);
599 	if (ret)
600 		goto err_irq;
601 
602 
603 	INIT_LIST_HEAD(&ucb->devs);
604 	mutex_lock(&ucb1x00_mutex);
605 	list_add(&ucb->node, &ucb1x00_devices);
606 	list_for_each_entry(drv, &ucb1x00_drivers, node) {
607 		ucb1x00_add_dev(ucb, drv);
608 	}
609 	mutex_unlock(&ucb1x00_mutex);
610 
611 	goto out;
612 
613  err_irq:
614 	free_irq(ucb->irq, ucb);
615  err_gpio:
616 	if (ucb->gpio.base != -1)
617 		temp = gpiochip_remove(&ucb->gpio);
618  err_free:
619 	kfree(ucb);
620  err_disable:
621 	mcp_disable(mcp);
622  out:
623 	return ret;
624 }
625 
626 static void ucb1x00_remove(struct mcp *mcp)
627 {
628 	struct ucb1x00 *ucb = mcp_get_drvdata(mcp);
629 	struct list_head *l, *n;
630 	int ret;
631 
632 	mutex_lock(&ucb1x00_mutex);
633 	list_del(&ucb->node);
634 	list_for_each_safe(l, n, &ucb->devs) {
635 		struct ucb1x00_dev *dev = list_entry(l, struct ucb1x00_dev, dev_node);
636 		ucb1x00_remove_dev(dev);
637 	}
638 	mutex_unlock(&ucb1x00_mutex);
639 
640 	if (ucb->gpio.base != -1) {
641 		ret = gpiochip_remove(&ucb->gpio);
642 		if (ret)
643 			dev_err(&ucb->dev, "Can't remove gpio chip: %d\n", ret);
644 	}
645 
646 	free_irq(ucb->irq, ucb);
647 	device_unregister(&ucb->dev);
648 }
649 
650 int ucb1x00_register_driver(struct ucb1x00_driver *drv)
651 {
652 	struct ucb1x00 *ucb;
653 
654 	INIT_LIST_HEAD(&drv->devs);
655 	mutex_lock(&ucb1x00_mutex);
656 	list_add(&drv->node, &ucb1x00_drivers);
657 	list_for_each_entry(ucb, &ucb1x00_devices, node) {
658 		ucb1x00_add_dev(ucb, drv);
659 	}
660 	mutex_unlock(&ucb1x00_mutex);
661 	return 0;
662 }
663 
664 void ucb1x00_unregister_driver(struct ucb1x00_driver *drv)
665 {
666 	struct list_head *n, *l;
667 
668 	mutex_lock(&ucb1x00_mutex);
669 	list_del(&drv->node);
670 	list_for_each_safe(l, n, &drv->devs) {
671 		struct ucb1x00_dev *dev = list_entry(l, struct ucb1x00_dev, drv_node);
672 		ucb1x00_remove_dev(dev);
673 	}
674 	mutex_unlock(&ucb1x00_mutex);
675 }
676 
677 static int ucb1x00_suspend(struct mcp *mcp, pm_message_t state)
678 {
679 	struct ucb1x00 *ucb = mcp_get_drvdata(mcp);
680 	struct ucb1x00_dev *dev;
681 
682 	mutex_lock(&ucb1x00_mutex);
683 	list_for_each_entry(dev, &ucb->devs, dev_node) {
684 		if (dev->drv->suspend)
685 			dev->drv->suspend(dev, state);
686 	}
687 	mutex_unlock(&ucb1x00_mutex);
688 	return 0;
689 }
690 
691 static int ucb1x00_resume(struct mcp *mcp)
692 {
693 	struct ucb1x00 *ucb = mcp_get_drvdata(mcp);
694 	struct ucb1x00_dev *dev;
695 
696 	ucb1x00_reg_write(ucb, UCB_IO_DATA, ucb->io_out);
697 	ucb1x00_reg_write(ucb, UCB_IO_DIR, ucb->io_dir);
698 	mutex_lock(&ucb1x00_mutex);
699 	list_for_each_entry(dev, &ucb->devs, dev_node) {
700 		if (dev->drv->resume)
701 			dev->drv->resume(dev);
702 	}
703 	mutex_unlock(&ucb1x00_mutex);
704 	return 0;
705 }
706 
707 static struct mcp_driver ucb1x00_driver = {
708 	.drv		= {
709 		.name	= "ucb1x00",
710 	},
711 	.probe		= ucb1x00_probe,
712 	.remove		= ucb1x00_remove,
713 	.suspend	= ucb1x00_suspend,
714 	.resume		= ucb1x00_resume,
715 };
716 
717 static int __init ucb1x00_init(void)
718 {
719 	int ret = class_register(&ucb1x00_class);
720 	if (ret == 0) {
721 		ret = mcp_driver_register(&ucb1x00_driver);
722 		if (ret)
723 			class_unregister(&ucb1x00_class);
724 	}
725 	return ret;
726 }
727 
728 static void __exit ucb1x00_exit(void)
729 {
730 	mcp_driver_unregister(&ucb1x00_driver);
731 	class_unregister(&ucb1x00_class);
732 }
733 
734 module_init(ucb1x00_init);
735 module_exit(ucb1x00_exit);
736 
737 EXPORT_SYMBOL(ucb1x00_io_set_dir);
738 EXPORT_SYMBOL(ucb1x00_io_write);
739 EXPORT_SYMBOL(ucb1x00_io_read);
740 
741 EXPORT_SYMBOL(ucb1x00_adc_enable);
742 EXPORT_SYMBOL(ucb1x00_adc_read);
743 EXPORT_SYMBOL(ucb1x00_adc_disable);
744 
745 EXPORT_SYMBOL(ucb1x00_hook_irq);
746 EXPORT_SYMBOL(ucb1x00_free_irq);
747 EXPORT_SYMBOL(ucb1x00_enable_irq);
748 EXPORT_SYMBOL(ucb1x00_disable_irq);
749 
750 EXPORT_SYMBOL(ucb1x00_register_driver);
751 EXPORT_SYMBOL(ucb1x00_unregister_driver);
752 
753 MODULE_AUTHOR("Russell King <rmk@arm.linux.org.uk>");
754 MODULE_DESCRIPTION("UCB1x00 core driver");
755 MODULE_LICENSE("GPL");
756