xref: /linux/drivers/mfd/ucb1x00-core.c (revision 497e6b37b0099dc415578488287fd84fb74433eb)
1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3  *  linux/drivers/mfd/ucb1x00-core.c
4  *
5  *  Copyright (C) 2001 Russell King, All Rights Reserved.
6  *
7  *  The UCB1x00 core driver provides basic services for handling IO,
8  *  the ADC, interrupts, and accessing registers.  It is designed
9  *  such that everything goes through this layer, thereby providing
10  *  a consistent locking methodology, as well as allowing the drivers
11  *  to be used on other non-MCP-enabled hardware platforms.
12  *
13  *  Note that all locks are private to this file.  Nothing else may
14  *  touch them.
15  */
16 #include <linux/module.h>
17 #include <linux/kernel.h>
18 #include <linux/sched.h>
19 #include <linux/slab.h>
20 #include <linux/init.h>
21 #include <linux/errno.h>
22 #include <linux/interrupt.h>
23 #include <linux/irq.h>
24 #include <linux/device.h>
25 #include <linux/mutex.h>
26 #include <linux/mfd/ucb1x00.h>
27 #include <linux/pm.h>
28 #include <linux/gpio/driver.h>
29 
30 static DEFINE_MUTEX(ucb1x00_mutex);
31 static LIST_HEAD(ucb1x00_drivers);
32 static LIST_HEAD(ucb1x00_devices);
33 
34 /**
35  *	ucb1x00_io_set_dir - set IO direction
36  *	@ucb: UCB1x00 structure describing chip
37  *	@in:  bitfield of IO pins to be set as inputs
38  *	@out: bitfield of IO pins to be set as outputs
39  *
40  *	Set the IO direction of the ten general purpose IO pins on
41  *	the UCB1x00 chip.  The @in bitfield has priority over the
42  *	@out bitfield, in that if you specify a pin as both input
43  *	and output, it will end up as an input.
44  *
45  *	ucb1x00_enable must have been called to enable the comms
46  *	before using this function.
47  *
48  *	This function takes a spinlock, disabling interrupts.
49  */
50 void ucb1x00_io_set_dir(struct ucb1x00 *ucb, unsigned int in, unsigned int out)
51 {
52 	unsigned long flags;
53 
54 	spin_lock_irqsave(&ucb->io_lock, flags);
55 	ucb->io_dir |= out;
56 	ucb->io_dir &= ~in;
57 
58 	ucb1x00_reg_write(ucb, UCB_IO_DIR, ucb->io_dir);
59 	spin_unlock_irqrestore(&ucb->io_lock, flags);
60 }
61 
62 /**
63  *	ucb1x00_io_write - set or clear IO outputs
64  *	@ucb:   UCB1x00 structure describing chip
65  *	@set:   bitfield of IO pins to set to logic '1'
66  *	@clear: bitfield of IO pins to set to logic '0'
67  *
68  *	Set the IO output state of the specified IO pins.  The value
69  *	is retained if the pins are subsequently configured as inputs.
70  *	The @clear bitfield has priority over the @set bitfield -
71  *	outputs will be cleared.
72  *
73  *	ucb1x00_enable must have been called to enable the comms
74  *	before using this function.
75  *
76  *	This function takes a spinlock, disabling interrupts.
77  */
78 void ucb1x00_io_write(struct ucb1x00 *ucb, unsigned int set, unsigned int clear)
79 {
80 	unsigned long flags;
81 
82 	spin_lock_irqsave(&ucb->io_lock, flags);
83 	ucb->io_out |= set;
84 	ucb->io_out &= ~clear;
85 
86 	ucb1x00_reg_write(ucb, UCB_IO_DATA, ucb->io_out);
87 	spin_unlock_irqrestore(&ucb->io_lock, flags);
88 }
89 
90 /**
91  *	ucb1x00_io_read - read the current state of the IO pins
92  *	@ucb: UCB1x00 structure describing chip
93  *
94  *	Return a bitfield describing the logic state of the ten
95  *	general purpose IO pins.
96  *
97  *	ucb1x00_enable must have been called to enable the comms
98  *	before using this function.
99  *
100  *	This function does not take any mutexes or spinlocks.
101  */
102 unsigned int ucb1x00_io_read(struct ucb1x00 *ucb)
103 {
104 	return ucb1x00_reg_read(ucb, UCB_IO_DATA);
105 }
106 
107 static void ucb1x00_gpio_set(struct gpio_chip *chip, unsigned offset, int value)
108 {
109 	struct ucb1x00 *ucb = gpiochip_get_data(chip);
110 	unsigned long flags;
111 
112 	spin_lock_irqsave(&ucb->io_lock, flags);
113 	if (value)
114 		ucb->io_out |= 1 << offset;
115 	else
116 		ucb->io_out &= ~(1 << offset);
117 
118 	ucb1x00_enable(ucb);
119 	ucb1x00_reg_write(ucb, UCB_IO_DATA, ucb->io_out);
120 	ucb1x00_disable(ucb);
121 	spin_unlock_irqrestore(&ucb->io_lock, flags);
122 }
123 
124 static int ucb1x00_gpio_get(struct gpio_chip *chip, unsigned offset)
125 {
126 	struct ucb1x00 *ucb = gpiochip_get_data(chip);
127 	unsigned val;
128 
129 	ucb1x00_enable(ucb);
130 	val = ucb1x00_reg_read(ucb, UCB_IO_DATA);
131 	ucb1x00_disable(ucb);
132 
133 	return !!(val & (1 << offset));
134 }
135 
136 static int ucb1x00_gpio_direction_input(struct gpio_chip *chip, unsigned offset)
137 {
138 	struct ucb1x00 *ucb = gpiochip_get_data(chip);
139 	unsigned long flags;
140 
141 	spin_lock_irqsave(&ucb->io_lock, flags);
142 	ucb->io_dir &= ~(1 << offset);
143 	ucb1x00_enable(ucb);
144 	ucb1x00_reg_write(ucb, UCB_IO_DIR, ucb->io_dir);
145 	ucb1x00_disable(ucb);
146 	spin_unlock_irqrestore(&ucb->io_lock, flags);
147 
148 	return 0;
149 }
150 
151 static int ucb1x00_gpio_direction_output(struct gpio_chip *chip, unsigned offset
152 		, int value)
153 {
154 	struct ucb1x00 *ucb = gpiochip_get_data(chip);
155 	unsigned long flags;
156 	unsigned old, mask = 1 << offset;
157 
158 	spin_lock_irqsave(&ucb->io_lock, flags);
159 	old = ucb->io_out;
160 	if (value)
161 		ucb->io_out |= mask;
162 	else
163 		ucb->io_out &= ~mask;
164 
165 	ucb1x00_enable(ucb);
166 	if (old != ucb->io_out)
167 		ucb1x00_reg_write(ucb, UCB_IO_DATA, ucb->io_out);
168 
169 	if (!(ucb->io_dir & mask)) {
170 		ucb->io_dir |= mask;
171 		ucb1x00_reg_write(ucb, UCB_IO_DIR, ucb->io_dir);
172 	}
173 	ucb1x00_disable(ucb);
174 	spin_unlock_irqrestore(&ucb->io_lock, flags);
175 
176 	return 0;
177 }
178 
179 static int ucb1x00_to_irq(struct gpio_chip *chip, unsigned offset)
180 {
181 	struct ucb1x00 *ucb = gpiochip_get_data(chip);
182 
183 	return ucb->irq_base > 0 ? ucb->irq_base + offset : -ENXIO;
184 }
185 
186 /*
187  * UCB1300 data sheet says we must:
188  *  1. enable ADC	=> 5us (including reference startup time)
189  *  2. select input	=> 51*tsibclk  => 4.3us
190  *  3. start conversion	=> 102*tsibclk => 8.5us
191  * (tsibclk = 1/11981000)
192  * Period between SIB 128-bit frames = 10.7us
193  */
194 
195 /**
196  *	ucb1x00_adc_enable - enable the ADC converter
197  *	@ucb: UCB1x00 structure describing chip
198  *
199  *	Enable the ucb1x00 and ADC converter on the UCB1x00 for use.
200  *	Any code wishing to use the ADC converter must call this
201  *	function prior to using it.
202  *
203  *	This function takes the ADC mutex to prevent two or more
204  *	concurrent uses, and therefore may sleep.  As a result, it
205  *	can only be called from process context, not interrupt
206  *	context.
207  *
208  *	You should release the ADC as soon as possible using
209  *	ucb1x00_adc_disable.
210  */
211 void ucb1x00_adc_enable(struct ucb1x00 *ucb)
212 {
213 	mutex_lock(&ucb->adc_mutex);
214 
215 	ucb->adc_cr |= UCB_ADC_ENA;
216 
217 	ucb1x00_enable(ucb);
218 	ucb1x00_reg_write(ucb, UCB_ADC_CR, ucb->adc_cr);
219 }
220 
221 /**
222  *	ucb1x00_adc_read - read the specified ADC channel
223  *	@ucb: UCB1x00 structure describing chip
224  *	@adc_channel: ADC channel mask
225  *	@sync: wait for syncronisation pulse.
226  *
227  *	Start an ADC conversion and wait for the result.  Note that
228  *	synchronised ADC conversions (via the ADCSYNC pin) must wait
229  *	until the trigger is asserted and the conversion is finished.
230  *
231  *	This function currently spins waiting for the conversion to
232  *	complete (2 frames max without sync).
233  *
234  *	If called for a synchronised ADC conversion, it may sleep
235  *	with the ADC mutex held.
236  */
237 unsigned int ucb1x00_adc_read(struct ucb1x00 *ucb, int adc_channel, int sync)
238 {
239 	unsigned int val;
240 
241 	if (sync)
242 		adc_channel |= UCB_ADC_SYNC_ENA;
243 
244 	ucb1x00_reg_write(ucb, UCB_ADC_CR, ucb->adc_cr | adc_channel);
245 	ucb1x00_reg_write(ucb, UCB_ADC_CR, ucb->adc_cr | adc_channel | UCB_ADC_START);
246 
247 	for (;;) {
248 		val = ucb1x00_reg_read(ucb, UCB_ADC_DATA);
249 		if (val & UCB_ADC_DAT_VAL)
250 			break;
251 		/* yield to other processes */
252 		set_current_state(TASK_INTERRUPTIBLE);
253 		schedule_timeout(1);
254 	}
255 
256 	return UCB_ADC_DAT(val);
257 }
258 
259 /**
260  *	ucb1x00_adc_disable - disable the ADC converter
261  *	@ucb: UCB1x00 structure describing chip
262  *
263  *	Disable the ADC converter and release the ADC mutex.
264  */
265 void ucb1x00_adc_disable(struct ucb1x00 *ucb)
266 {
267 	ucb->adc_cr &= ~UCB_ADC_ENA;
268 	ucb1x00_reg_write(ucb, UCB_ADC_CR, ucb->adc_cr);
269 	ucb1x00_disable(ucb);
270 
271 	mutex_unlock(&ucb->adc_mutex);
272 }
273 
274 /*
275  * UCB1x00 Interrupt handling.
276  *
277  * The UCB1x00 can generate interrupts when the SIBCLK is stopped.
278  * Since we need to read an internal register, we must re-enable
279  * SIBCLK to talk to the chip.  We leave the clock running until
280  * we have finished processing all interrupts from the chip.
281  */
282 static void ucb1x00_irq(struct irq_desc *desc)
283 {
284 	struct ucb1x00 *ucb = irq_desc_get_handler_data(desc);
285 	unsigned int isr, i;
286 
287 	ucb1x00_enable(ucb);
288 	isr = ucb1x00_reg_read(ucb, UCB_IE_STATUS);
289 	ucb1x00_reg_write(ucb, UCB_IE_CLEAR, isr);
290 	ucb1x00_reg_write(ucb, UCB_IE_CLEAR, 0);
291 
292 	for (i = 0; i < 16 && isr; i++, isr >>= 1)
293 		if (isr & 1)
294 			generic_handle_irq(ucb->irq_base + i);
295 	ucb1x00_disable(ucb);
296 }
297 
298 static void ucb1x00_irq_update(struct ucb1x00 *ucb, unsigned mask)
299 {
300 	ucb1x00_enable(ucb);
301 	if (ucb->irq_ris_enbl & mask)
302 		ucb1x00_reg_write(ucb, UCB_IE_RIS, ucb->irq_ris_enbl &
303 				  ucb->irq_mask);
304 	if (ucb->irq_fal_enbl & mask)
305 		ucb1x00_reg_write(ucb, UCB_IE_FAL, ucb->irq_fal_enbl &
306 				  ucb->irq_mask);
307 	ucb1x00_disable(ucb);
308 }
309 
310 static void ucb1x00_irq_noop(struct irq_data *data)
311 {
312 }
313 
314 static void ucb1x00_irq_mask(struct irq_data *data)
315 {
316 	struct ucb1x00 *ucb = irq_data_get_irq_chip_data(data);
317 	unsigned mask = 1 << (data->irq - ucb->irq_base);
318 
319 	raw_spin_lock(&ucb->irq_lock);
320 	ucb->irq_mask &= ~mask;
321 	ucb1x00_irq_update(ucb, mask);
322 	raw_spin_unlock(&ucb->irq_lock);
323 }
324 
325 static void ucb1x00_irq_unmask(struct irq_data *data)
326 {
327 	struct ucb1x00 *ucb = irq_data_get_irq_chip_data(data);
328 	unsigned mask = 1 << (data->irq - ucb->irq_base);
329 
330 	raw_spin_lock(&ucb->irq_lock);
331 	ucb->irq_mask |= mask;
332 	ucb1x00_irq_update(ucb, mask);
333 	raw_spin_unlock(&ucb->irq_lock);
334 }
335 
336 static int ucb1x00_irq_set_type(struct irq_data *data, unsigned int type)
337 {
338 	struct ucb1x00 *ucb = irq_data_get_irq_chip_data(data);
339 	unsigned mask = 1 << (data->irq - ucb->irq_base);
340 
341 	raw_spin_lock(&ucb->irq_lock);
342 	if (type & IRQ_TYPE_EDGE_RISING)
343 		ucb->irq_ris_enbl |= mask;
344 	else
345 		ucb->irq_ris_enbl &= ~mask;
346 
347 	if (type & IRQ_TYPE_EDGE_FALLING)
348 		ucb->irq_fal_enbl |= mask;
349 	else
350 		ucb->irq_fal_enbl &= ~mask;
351 	if (ucb->irq_mask & mask) {
352 		ucb1x00_reg_write(ucb, UCB_IE_RIS, ucb->irq_ris_enbl &
353 				  ucb->irq_mask);
354 		ucb1x00_reg_write(ucb, UCB_IE_FAL, ucb->irq_fal_enbl &
355 				  ucb->irq_mask);
356 	}
357 	raw_spin_unlock(&ucb->irq_lock);
358 
359 	return 0;
360 }
361 
362 static int ucb1x00_irq_set_wake(struct irq_data *data, unsigned int on)
363 {
364 	struct ucb1x00 *ucb = irq_data_get_irq_chip_data(data);
365 	struct ucb1x00_plat_data *pdata = ucb->mcp->attached_device.platform_data;
366 	unsigned mask = 1 << (data->irq - ucb->irq_base);
367 
368 	if (!pdata || !pdata->can_wakeup)
369 		return -EINVAL;
370 
371 	raw_spin_lock(&ucb->irq_lock);
372 	if (on)
373 		ucb->irq_wake |= mask;
374 	else
375 		ucb->irq_wake &= ~mask;
376 	raw_spin_unlock(&ucb->irq_lock);
377 
378 	return 0;
379 }
380 
381 static struct irq_chip ucb1x00_irqchip = {
382 	.name = "ucb1x00",
383 	.irq_ack = ucb1x00_irq_noop,
384 	.irq_mask = ucb1x00_irq_mask,
385 	.irq_unmask = ucb1x00_irq_unmask,
386 	.irq_set_type = ucb1x00_irq_set_type,
387 	.irq_set_wake = ucb1x00_irq_set_wake,
388 };
389 
390 static int ucb1x00_add_dev(struct ucb1x00 *ucb, struct ucb1x00_driver *drv)
391 {
392 	struct ucb1x00_dev *dev;
393 	int ret;
394 
395 	dev = kmalloc(sizeof(struct ucb1x00_dev), GFP_KERNEL);
396 	if (!dev)
397 		return -ENOMEM;
398 
399 	dev->ucb = ucb;
400 	dev->drv = drv;
401 
402 	ret = drv->add(dev);
403 	if (ret) {
404 		kfree(dev);
405 		return ret;
406 	}
407 
408 	list_add_tail(&dev->dev_node, &ucb->devs);
409 	list_add_tail(&dev->drv_node, &drv->devs);
410 
411 	return ret;
412 }
413 
414 static void ucb1x00_remove_dev(struct ucb1x00_dev *dev)
415 {
416 	dev->drv->remove(dev);
417 	list_del(&dev->dev_node);
418 	list_del(&dev->drv_node);
419 	kfree(dev);
420 }
421 
422 /*
423  * Try to probe our interrupt, rather than relying on lots of
424  * hard-coded machine dependencies.  For reference, the expected
425  * IRQ mappings are:
426  *
427  *  	Machine		Default IRQ
428  *	adsbitsy	IRQ_GPCIN4
429  *	cerf		IRQ_GPIO_UCB1200_IRQ
430  *	flexanet	IRQ_GPIO_GUI
431  *	freebird	IRQ_GPIO_FREEBIRD_UCB1300_IRQ
432  *	graphicsclient	ADS_EXT_IRQ(8)
433  *	graphicsmaster	ADS_EXT_IRQ(8)
434  *	lart		LART_IRQ_UCB1200
435  *	omnimeter	IRQ_GPIO23
436  *	pfs168		IRQ_GPIO_UCB1300_IRQ
437  *	simpad		IRQ_GPIO_UCB1300_IRQ
438  *	shannon		SHANNON_IRQ_GPIO_IRQ_CODEC
439  *	yopy		IRQ_GPIO_UCB1200_IRQ
440  */
441 static int ucb1x00_detect_irq(struct ucb1x00 *ucb)
442 {
443 	unsigned long mask;
444 
445 	mask = probe_irq_on();
446 
447 	/*
448 	 * Enable the ADC interrupt.
449 	 */
450 	ucb1x00_reg_write(ucb, UCB_IE_RIS, UCB_IE_ADC);
451 	ucb1x00_reg_write(ucb, UCB_IE_FAL, UCB_IE_ADC);
452 	ucb1x00_reg_write(ucb, UCB_IE_CLEAR, 0xffff);
453 	ucb1x00_reg_write(ucb, UCB_IE_CLEAR, 0);
454 
455 	/*
456 	 * Cause an ADC interrupt.
457 	 */
458 	ucb1x00_reg_write(ucb, UCB_ADC_CR, UCB_ADC_ENA);
459 	ucb1x00_reg_write(ucb, UCB_ADC_CR, UCB_ADC_ENA | UCB_ADC_START);
460 
461 	/*
462 	 * Wait for the conversion to complete.
463 	 */
464 	while ((ucb1x00_reg_read(ucb, UCB_ADC_DATA) & UCB_ADC_DAT_VAL) == 0);
465 	ucb1x00_reg_write(ucb, UCB_ADC_CR, 0);
466 
467 	/*
468 	 * Disable and clear interrupt.
469 	 */
470 	ucb1x00_reg_write(ucb, UCB_IE_RIS, 0);
471 	ucb1x00_reg_write(ucb, UCB_IE_FAL, 0);
472 	ucb1x00_reg_write(ucb, UCB_IE_CLEAR, 0xffff);
473 	ucb1x00_reg_write(ucb, UCB_IE_CLEAR, 0);
474 
475 	/*
476 	 * Read triggered interrupt.
477 	 */
478 	return probe_irq_off(mask);
479 }
480 
481 static void ucb1x00_release(struct device *dev)
482 {
483 	struct ucb1x00 *ucb = classdev_to_ucb1x00(dev);
484 	kfree(ucb);
485 }
486 
487 static struct class ucb1x00_class = {
488 	.name		= "ucb1x00",
489 	.dev_release	= ucb1x00_release,
490 };
491 
492 static int ucb1x00_probe(struct mcp *mcp)
493 {
494 	struct ucb1x00_plat_data *pdata = mcp->attached_device.platform_data;
495 	struct ucb1x00_driver *drv;
496 	struct ucb1x00 *ucb;
497 	unsigned id, i, irq_base;
498 	int ret = -ENODEV;
499 
500 	/* Tell the platform to deassert the UCB1x00 reset */
501 	if (pdata && pdata->reset)
502 		pdata->reset(UCB_RST_PROBE);
503 
504 	mcp_enable(mcp);
505 	id = mcp_reg_read(mcp, UCB_ID);
506 	mcp_disable(mcp);
507 
508 	if (id != UCB_ID_1200 && id != UCB_ID_1300 && id != UCB_ID_TC35143) {
509 		printk(KERN_WARNING "UCB1x00 ID not found: %04x\n", id);
510 		goto out;
511 	}
512 
513 	ucb = kzalloc(sizeof(struct ucb1x00), GFP_KERNEL);
514 	ret = -ENOMEM;
515 	if (!ucb)
516 		goto out;
517 
518 	device_initialize(&ucb->dev);
519 	ucb->dev.class = &ucb1x00_class;
520 	ucb->dev.parent = &mcp->attached_device;
521 	dev_set_name(&ucb->dev, "ucb1x00");
522 
523 	raw_spin_lock_init(&ucb->irq_lock);
524 	spin_lock_init(&ucb->io_lock);
525 	mutex_init(&ucb->adc_mutex);
526 
527 	ucb->id  = id;
528 	ucb->mcp = mcp;
529 
530 	ret = device_add(&ucb->dev);
531 	if (ret)
532 		goto err_dev_add;
533 
534 	ucb1x00_enable(ucb);
535 	ucb->irq = ucb1x00_detect_irq(ucb);
536 	ucb1x00_disable(ucb);
537 	if (!ucb->irq) {
538 		dev_err(&ucb->dev, "IRQ probe failed\n");
539 		ret = -ENODEV;
540 		goto err_no_irq;
541 	}
542 
543 	ucb->gpio.base = -1;
544 	irq_base = pdata ? pdata->irq_base : 0;
545 	ucb->irq_base = irq_alloc_descs(-1, irq_base, 16, -1);
546 	if (ucb->irq_base < 0) {
547 		dev_err(&ucb->dev, "unable to allocate 16 irqs: %d\n",
548 			ucb->irq_base);
549 		ret = ucb->irq_base;
550 		goto err_irq_alloc;
551 	}
552 
553 	for (i = 0; i < 16; i++) {
554 		unsigned irq = ucb->irq_base + i;
555 
556 		irq_set_chip_and_handler(irq, &ucb1x00_irqchip, handle_edge_irq);
557 		irq_set_chip_data(irq, ucb);
558 		irq_clear_status_flags(irq, IRQ_NOREQUEST);
559 	}
560 
561 	irq_set_irq_type(ucb->irq, IRQ_TYPE_EDGE_RISING);
562 	irq_set_chained_handler_and_data(ucb->irq, ucb1x00_irq, ucb);
563 
564 	if (pdata && pdata->gpio_base) {
565 		ucb->gpio.label = dev_name(&ucb->dev);
566 		ucb->gpio.parent = &ucb->dev;
567 		ucb->gpio.owner = THIS_MODULE;
568 		ucb->gpio.base = pdata->gpio_base;
569 		ucb->gpio.ngpio = 10;
570 		ucb->gpio.set = ucb1x00_gpio_set;
571 		ucb->gpio.get = ucb1x00_gpio_get;
572 		ucb->gpio.direction_input = ucb1x00_gpio_direction_input;
573 		ucb->gpio.direction_output = ucb1x00_gpio_direction_output;
574 		ucb->gpio.to_irq = ucb1x00_to_irq;
575 		ret = gpiochip_add_data(&ucb->gpio, ucb);
576 		if (ret)
577 			goto err_gpio_add;
578 	} else
579 		dev_info(&ucb->dev, "gpio_base not set so no gpiolib support");
580 
581 	mcp_set_drvdata(mcp, ucb);
582 
583 	if (pdata)
584 		device_set_wakeup_capable(&ucb->dev, pdata->can_wakeup);
585 
586 	INIT_LIST_HEAD(&ucb->devs);
587 	mutex_lock(&ucb1x00_mutex);
588 	list_add_tail(&ucb->node, &ucb1x00_devices);
589 	list_for_each_entry(drv, &ucb1x00_drivers, node) {
590 		ucb1x00_add_dev(ucb, drv);
591 	}
592 	mutex_unlock(&ucb1x00_mutex);
593 
594 	return ret;
595 
596  err_gpio_add:
597 	irq_set_chained_handler(ucb->irq, NULL);
598  err_irq_alloc:
599 	if (ucb->irq_base > 0)
600 		irq_free_descs(ucb->irq_base, 16);
601  err_no_irq:
602 	device_del(&ucb->dev);
603  err_dev_add:
604 	put_device(&ucb->dev);
605  out:
606 	if (pdata && pdata->reset)
607 		pdata->reset(UCB_RST_PROBE_FAIL);
608 	return ret;
609 }
610 
611 static void ucb1x00_remove(struct mcp *mcp)
612 {
613 	struct ucb1x00_plat_data *pdata = mcp->attached_device.platform_data;
614 	struct ucb1x00 *ucb = mcp_get_drvdata(mcp);
615 	struct list_head *l, *n;
616 
617 	mutex_lock(&ucb1x00_mutex);
618 	list_del(&ucb->node);
619 	list_for_each_safe(l, n, &ucb->devs) {
620 		struct ucb1x00_dev *dev = list_entry(l, struct ucb1x00_dev, dev_node);
621 		ucb1x00_remove_dev(dev);
622 	}
623 	mutex_unlock(&ucb1x00_mutex);
624 
625 	if (ucb->gpio.base != -1)
626 		gpiochip_remove(&ucb->gpio);
627 
628 	irq_set_chained_handler(ucb->irq, NULL);
629 	irq_free_descs(ucb->irq_base, 16);
630 	device_unregister(&ucb->dev);
631 
632 	if (pdata && pdata->reset)
633 		pdata->reset(UCB_RST_REMOVE);
634 }
635 
636 int ucb1x00_register_driver(struct ucb1x00_driver *drv)
637 {
638 	struct ucb1x00 *ucb;
639 
640 	INIT_LIST_HEAD(&drv->devs);
641 	mutex_lock(&ucb1x00_mutex);
642 	list_add_tail(&drv->node, &ucb1x00_drivers);
643 	list_for_each_entry(ucb, &ucb1x00_devices, node) {
644 		ucb1x00_add_dev(ucb, drv);
645 	}
646 	mutex_unlock(&ucb1x00_mutex);
647 	return 0;
648 }
649 
650 void ucb1x00_unregister_driver(struct ucb1x00_driver *drv)
651 {
652 	struct list_head *n, *l;
653 
654 	mutex_lock(&ucb1x00_mutex);
655 	list_del(&drv->node);
656 	list_for_each_safe(l, n, &drv->devs) {
657 		struct ucb1x00_dev *dev = list_entry(l, struct ucb1x00_dev, drv_node);
658 		ucb1x00_remove_dev(dev);
659 	}
660 	mutex_unlock(&ucb1x00_mutex);
661 }
662 
663 static int ucb1x00_suspend(struct device *dev)
664 {
665 	struct ucb1x00_plat_data *pdata = dev_get_platdata(dev);
666 	struct ucb1x00 *ucb = dev_get_drvdata(dev);
667 	struct ucb1x00_dev *udev;
668 
669 	mutex_lock(&ucb1x00_mutex);
670 	list_for_each_entry(udev, &ucb->devs, dev_node) {
671 		if (udev->drv->suspend)
672 			udev->drv->suspend(udev);
673 	}
674 	mutex_unlock(&ucb1x00_mutex);
675 
676 	if (ucb->irq_wake) {
677 		unsigned long flags;
678 
679 		raw_spin_lock_irqsave(&ucb->irq_lock, flags);
680 		ucb1x00_enable(ucb);
681 		ucb1x00_reg_write(ucb, UCB_IE_RIS, ucb->irq_ris_enbl &
682 				  ucb->irq_wake);
683 		ucb1x00_reg_write(ucb, UCB_IE_FAL, ucb->irq_fal_enbl &
684 				  ucb->irq_wake);
685 		ucb1x00_disable(ucb);
686 		raw_spin_unlock_irqrestore(&ucb->irq_lock, flags);
687 
688 		enable_irq_wake(ucb->irq);
689 	} else if (pdata && pdata->reset)
690 		pdata->reset(UCB_RST_SUSPEND);
691 
692 	return 0;
693 }
694 
695 static int ucb1x00_resume(struct device *dev)
696 {
697 	struct ucb1x00_plat_data *pdata = dev_get_platdata(dev);
698 	struct ucb1x00 *ucb = dev_get_drvdata(dev);
699 	struct ucb1x00_dev *udev;
700 
701 	if (!ucb->irq_wake && pdata && pdata->reset)
702 		pdata->reset(UCB_RST_RESUME);
703 
704 	ucb1x00_enable(ucb);
705 	ucb1x00_reg_write(ucb, UCB_IO_DATA, ucb->io_out);
706 	ucb1x00_reg_write(ucb, UCB_IO_DIR, ucb->io_dir);
707 
708 	if (ucb->irq_wake) {
709 		unsigned long flags;
710 
711 		raw_spin_lock_irqsave(&ucb->irq_lock, flags);
712 		ucb1x00_reg_write(ucb, UCB_IE_RIS, ucb->irq_ris_enbl &
713 				  ucb->irq_mask);
714 		ucb1x00_reg_write(ucb, UCB_IE_FAL, ucb->irq_fal_enbl &
715 				  ucb->irq_mask);
716 		raw_spin_unlock_irqrestore(&ucb->irq_lock, flags);
717 
718 		disable_irq_wake(ucb->irq);
719 	}
720 	ucb1x00_disable(ucb);
721 
722 	mutex_lock(&ucb1x00_mutex);
723 	list_for_each_entry(udev, &ucb->devs, dev_node) {
724 		if (udev->drv->resume)
725 			udev->drv->resume(udev);
726 	}
727 	mutex_unlock(&ucb1x00_mutex);
728 	return 0;
729 }
730 
731 static DEFINE_SIMPLE_DEV_PM_OPS(ucb1x00_pm_ops,
732 				ucb1x00_suspend, ucb1x00_resume);
733 
734 static struct mcp_driver ucb1x00_driver = {
735 	.drv		= {
736 		.name	= "ucb1x00",
737 		.owner	= THIS_MODULE,
738 		.pm	= pm_sleep_ptr(&ucb1x00_pm_ops),
739 	},
740 	.probe		= ucb1x00_probe,
741 	.remove		= ucb1x00_remove,
742 };
743 
744 static int __init ucb1x00_init(void)
745 {
746 	int ret = class_register(&ucb1x00_class);
747 	if (ret == 0) {
748 		ret = mcp_driver_register(&ucb1x00_driver);
749 		if (ret)
750 			class_unregister(&ucb1x00_class);
751 	}
752 	return ret;
753 }
754 
755 static void __exit ucb1x00_exit(void)
756 {
757 	mcp_driver_unregister(&ucb1x00_driver);
758 	class_unregister(&ucb1x00_class);
759 }
760 
761 module_init(ucb1x00_init);
762 module_exit(ucb1x00_exit);
763 
764 EXPORT_SYMBOL(ucb1x00_io_set_dir);
765 EXPORT_SYMBOL(ucb1x00_io_write);
766 EXPORT_SYMBOL(ucb1x00_io_read);
767 
768 EXPORT_SYMBOL(ucb1x00_adc_enable);
769 EXPORT_SYMBOL(ucb1x00_adc_read);
770 EXPORT_SYMBOL(ucb1x00_adc_disable);
771 
772 EXPORT_SYMBOL(ucb1x00_register_driver);
773 EXPORT_SYMBOL(ucb1x00_unregister_driver);
774 
775 MODULE_ALIAS("mcp:ucb1x00");
776 MODULE_AUTHOR("Russell King <rmk@arm.linux.org.uk>");
777 MODULE_DESCRIPTION("UCB1x00 core driver");
778 MODULE_LICENSE("GPL");
779