2 * linux/drivers/mfd/ucb1x00-core.c
4 * Copyright (C) 2001 Russell King, All Rights Reserved.
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.
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.
16 * Note that all locks are private to this file. Nothing else may
19 #include <linux/module.h>
20 #include <linux/kernel.h>
21 #include <linux/slab.h>
22 #include <linux/init.h>
23 #include <linux/errno.h>
24 #include <linux/interrupt.h>
25 #include <linux/device.h>
26 #include <linux/mutex.h>
29 #include <mach/hardware.h>
33 static DEFINE_MUTEX(ucb1x00_mutex);
34 static LIST_HEAD(ucb1x00_drivers);
35 static LIST_HEAD(ucb1x00_devices);
38 * ucb1x00_io_set_dir - set IO direction
39 * @ucb: UCB1x00 structure describing chip
40 * @in: bitfield of IO pins to be set as inputs
41 * @out: bitfield of IO pins to be set as outputs
43 * Set the IO direction of the ten general purpose IO pins on
44 * the UCB1x00 chip. The @in bitfield has priority over the
45 * @out bitfield, in that if you specify a pin as both input
46 * and output, it will end up as an input.
48 * ucb1x00_enable must have been called to enable the comms
49 * before using this function.
51 * This function takes a spinlock, disabling interrupts.
53 void ucb1x00_io_set_dir(struct ucb1x00 *ucb, unsigned int in, unsigned int out)
57 spin_lock_irqsave(&ucb->io_lock, flags);
61 ucb1x00_reg_write(ucb, UCB_IO_DIR, ucb->io_dir);
62 spin_unlock_irqrestore(&ucb->io_lock, flags);
66 * ucb1x00_io_write - set or clear IO outputs
67 * @ucb: UCB1x00 structure describing chip
68 * @set: bitfield of IO pins to set to logic '1'
69 * @clear: bitfield of IO pins to set to logic '0'
71 * Set the IO output state of the specified IO pins. The value
72 * is retained if the pins are subsequently configured as inputs.
73 * The @clear bitfield has priority over the @set bitfield -
74 * outputs will be cleared.
76 * ucb1x00_enable must have been called to enable the comms
77 * before using this function.
79 * This function takes a spinlock, disabling interrupts.
81 void ucb1x00_io_write(struct ucb1x00 *ucb, unsigned int set, unsigned int clear)
85 spin_lock_irqsave(&ucb->io_lock, flags);
87 ucb->io_out &= ~clear;
89 ucb1x00_reg_write(ucb, UCB_IO_DATA, ucb->io_out);
90 spin_unlock_irqrestore(&ucb->io_lock, flags);
94 * ucb1x00_io_read - read the current state of the IO pins
95 * @ucb: UCB1x00 structure describing chip
97 * Return a bitfield describing the logic state of the ten
98 * general purpose IO pins.
100 * ucb1x00_enable must have been called to enable the comms
101 * before using this function.
103 * This function does not take any semaphores or spinlocks.
105 unsigned int ucb1x00_io_read(struct ucb1x00 *ucb)
107 return ucb1x00_reg_read(ucb, UCB_IO_DATA);
111 * UCB1300 data sheet says we must:
112 * 1. enable ADC => 5us (including reference startup time)
113 * 2. select input => 51*tsibclk => 4.3us
114 * 3. start conversion => 102*tsibclk => 8.5us
115 * (tsibclk = 1/11981000)
116 * Period between SIB 128-bit frames = 10.7us
120 * ucb1x00_adc_enable - enable the ADC converter
121 * @ucb: UCB1x00 structure describing chip
123 * Enable the ucb1x00 and ADC converter on the UCB1x00 for use.
124 * Any code wishing to use the ADC converter must call this
125 * function prior to using it.
127 * This function takes the ADC semaphore to prevent two or more
128 * concurrent uses, and therefore may sleep. As a result, it
129 * can only be called from process context, not interrupt
132 * You should release the ADC as soon as possible using
133 * ucb1x00_adc_disable.
135 void ucb1x00_adc_enable(struct ucb1x00 *ucb)
139 ucb->adc_cr |= UCB_ADC_ENA;
142 ucb1x00_reg_write(ucb, UCB_ADC_CR, ucb->adc_cr);
146 * ucb1x00_adc_read - read the specified ADC channel
147 * @ucb: UCB1x00 structure describing chip
148 * @adc_channel: ADC channel mask
149 * @sync: wait for syncronisation pulse.
151 * Start an ADC conversion and wait for the result. Note that
152 * synchronised ADC conversions (via the ADCSYNC pin) must wait
153 * until the trigger is asserted and the conversion is finished.
155 * This function currently spins waiting for the conversion to
156 * complete (2 frames max without sync).
158 * If called for a synchronised ADC conversion, it may sleep
159 * with the ADC semaphore held.
161 unsigned int ucb1x00_adc_read(struct ucb1x00 *ucb, int adc_channel, int sync)
166 adc_channel |= UCB_ADC_SYNC_ENA;
168 ucb1x00_reg_write(ucb, UCB_ADC_CR, ucb->adc_cr | adc_channel);
169 ucb1x00_reg_write(ucb, UCB_ADC_CR, ucb->adc_cr | adc_channel | UCB_ADC_START);
172 val = ucb1x00_reg_read(ucb, UCB_ADC_DATA);
173 if (val & UCB_ADC_DAT_VAL)
175 /* yield to other processes */
176 set_current_state(TASK_INTERRUPTIBLE);
180 return UCB_ADC_DAT(val);
184 * ucb1x00_adc_disable - disable the ADC converter
185 * @ucb: UCB1x00 structure describing chip
187 * Disable the ADC converter and release the ADC semaphore.
189 void ucb1x00_adc_disable(struct ucb1x00 *ucb)
191 ucb->adc_cr &= ~UCB_ADC_ENA;
192 ucb1x00_reg_write(ucb, UCB_ADC_CR, ucb->adc_cr);
193 ucb1x00_disable(ucb);
199 * UCB1x00 Interrupt handling.
201 * The UCB1x00 can generate interrupts when the SIBCLK is stopped.
202 * Since we need to read an internal register, we must re-enable
203 * SIBCLK to talk to the chip. We leave the clock running until
204 * we have finished processing all interrupts from the chip.
206 static irqreturn_t ucb1x00_irq(int irqnr, void *devid)
208 struct ucb1x00 *ucb = devid;
209 struct ucb1x00_irq *irq;
213 isr = ucb1x00_reg_read(ucb, UCB_IE_STATUS);
214 ucb1x00_reg_write(ucb, UCB_IE_CLEAR, isr);
215 ucb1x00_reg_write(ucb, UCB_IE_CLEAR, 0);
217 for (i = 0, irq = ucb->irq_handler; i < 16 && isr; i++, isr >>= 1, irq++)
218 if (isr & 1 && irq->fn)
219 irq->fn(i, irq->devid);
220 ucb1x00_disable(ucb);
226 * ucb1x00_hook_irq - hook a UCB1x00 interrupt
227 * @ucb: UCB1x00 structure describing chip
228 * @idx: interrupt index
229 * @fn: function to call when interrupt is triggered
230 * @devid: device id to pass to interrupt handler
232 * Hook the specified interrupt. You can only register one handler
233 * for each interrupt source. The interrupt source is not enabled
234 * by this function; use ucb1x00_enable_irq instead.
236 * Interrupt handlers will be called with other interrupts enabled.
238 * Returns zero on success, or one of the following errors:
239 * -EINVAL if the interrupt index is invalid
240 * -EBUSY if the interrupt has already been hooked
242 int ucb1x00_hook_irq(struct ucb1x00 *ucb, unsigned int idx, void (*fn)(int, void *), void *devid)
244 struct ucb1x00_irq *irq;
248 irq = ucb->irq_handler + idx;
251 spin_lock_irq(&ucb->lock);
252 if (irq->fn == NULL) {
257 spin_unlock_irq(&ucb->lock);
263 * ucb1x00_enable_irq - enable an UCB1x00 interrupt source
264 * @ucb: UCB1x00 structure describing chip
265 * @idx: interrupt index
266 * @edges: interrupt edges to enable
268 * Enable the specified interrupt to trigger on %UCB_RISING,
269 * %UCB_FALLING or both edges. The interrupt should have been
270 * hooked by ucb1x00_hook_irq.
272 void ucb1x00_enable_irq(struct ucb1x00 *ucb, unsigned int idx, int edges)
277 spin_lock_irqsave(&ucb->lock, flags);
280 if (edges & UCB_RISING) {
281 ucb->irq_ris_enbl |= 1 << idx;
282 ucb1x00_reg_write(ucb, UCB_IE_RIS, ucb->irq_ris_enbl);
284 if (edges & UCB_FALLING) {
285 ucb->irq_fal_enbl |= 1 << idx;
286 ucb1x00_reg_write(ucb, UCB_IE_FAL, ucb->irq_fal_enbl);
288 ucb1x00_disable(ucb);
289 spin_unlock_irqrestore(&ucb->lock, flags);
294 * ucb1x00_disable_irq - disable an UCB1x00 interrupt source
295 * @ucb: UCB1x00 structure describing chip
296 * @edges: interrupt edges to disable
298 * Disable the specified interrupt triggering on the specified
299 * (%UCB_RISING, %UCB_FALLING or both) edges.
301 void ucb1x00_disable_irq(struct ucb1x00 *ucb, unsigned int idx, int edges)
306 spin_lock_irqsave(&ucb->lock, flags);
309 if (edges & UCB_RISING) {
310 ucb->irq_ris_enbl &= ~(1 << idx);
311 ucb1x00_reg_write(ucb, UCB_IE_RIS, ucb->irq_ris_enbl);
313 if (edges & UCB_FALLING) {
314 ucb->irq_fal_enbl &= ~(1 << idx);
315 ucb1x00_reg_write(ucb, UCB_IE_FAL, ucb->irq_fal_enbl);
317 ucb1x00_disable(ucb);
318 spin_unlock_irqrestore(&ucb->lock, flags);
323 * ucb1x00_free_irq - disable and free the specified UCB1x00 interrupt
324 * @ucb: UCB1x00 structure describing chip
325 * @idx: interrupt index
328 * Disable the interrupt source and remove the handler. devid must
329 * match the devid passed when hooking the interrupt.
331 * Returns zero on success, or one of the following errors:
332 * -EINVAL if the interrupt index is invalid
333 * -ENOENT if devid does not match
335 int ucb1x00_free_irq(struct ucb1x00 *ucb, unsigned int idx, void *devid)
337 struct ucb1x00_irq *irq;
343 irq = ucb->irq_handler + idx;
346 spin_lock_irq(&ucb->lock);
347 if (irq->devid == devid) {
348 ucb->irq_ris_enbl &= ~(1 << idx);
349 ucb->irq_fal_enbl &= ~(1 << idx);
352 ucb1x00_reg_write(ucb, UCB_IE_RIS, ucb->irq_ris_enbl);
353 ucb1x00_reg_write(ucb, UCB_IE_FAL, ucb->irq_fal_enbl);
354 ucb1x00_disable(ucb);
360 spin_unlock_irq(&ucb->lock);
364 printk(KERN_ERR "Freeing bad UCB1x00 irq %d\n", idx);
368 static int ucb1x00_add_dev(struct ucb1x00 *ucb, struct ucb1x00_driver *drv)
370 struct ucb1x00_dev *dev;
373 dev = kmalloc(sizeof(struct ucb1x00_dev), GFP_KERNEL);
381 list_add(&dev->dev_node, &ucb->devs);
382 list_add(&dev->drv_node, &drv->devs);
390 static void ucb1x00_remove_dev(struct ucb1x00_dev *dev)
392 dev->drv->remove(dev);
393 list_del(&dev->dev_node);
394 list_del(&dev->drv_node);
399 * Try to probe our interrupt, rather than relying on lots of
400 * hard-coded machine dependencies. For reference, the expected
403 * Machine Default IRQ
404 * adsbitsy IRQ_GPCIN4
405 * cerf IRQ_GPIO_UCB1200_IRQ
406 * flexanet IRQ_GPIO_GUI
407 * freebird IRQ_GPIO_FREEBIRD_UCB1300_IRQ
408 * graphicsclient ADS_EXT_IRQ(8)
409 * graphicsmaster ADS_EXT_IRQ(8)
410 * lart LART_IRQ_UCB1200
411 * omnimeter IRQ_GPIO23
412 * pfs168 IRQ_GPIO_UCB1300_IRQ
413 * simpad IRQ_GPIO_UCB1300_IRQ
414 * shannon SHANNON_IRQ_GPIO_IRQ_CODEC
415 * yopy IRQ_GPIO_UCB1200_IRQ
417 static int ucb1x00_detect_irq(struct ucb1x00 *ucb)
421 mask = probe_irq_on();
428 * Enable the ADC interrupt.
430 ucb1x00_reg_write(ucb, UCB_IE_RIS, UCB_IE_ADC);
431 ucb1x00_reg_write(ucb, UCB_IE_FAL, UCB_IE_ADC);
432 ucb1x00_reg_write(ucb, UCB_IE_CLEAR, 0xffff);
433 ucb1x00_reg_write(ucb, UCB_IE_CLEAR, 0);
436 * Cause an ADC interrupt.
438 ucb1x00_reg_write(ucb, UCB_ADC_CR, UCB_ADC_ENA);
439 ucb1x00_reg_write(ucb, UCB_ADC_CR, UCB_ADC_ENA | UCB_ADC_START);
442 * Wait for the conversion to complete.
444 while ((ucb1x00_reg_read(ucb, UCB_ADC_DATA) & UCB_ADC_DAT_VAL) == 0);
445 ucb1x00_reg_write(ucb, UCB_ADC_CR, 0);
448 * Disable and clear interrupt.
450 ucb1x00_reg_write(ucb, UCB_IE_RIS, 0);
451 ucb1x00_reg_write(ucb, UCB_IE_FAL, 0);
452 ucb1x00_reg_write(ucb, UCB_IE_CLEAR, 0xffff);
453 ucb1x00_reg_write(ucb, UCB_IE_CLEAR, 0);
456 * Read triggered interrupt.
458 return probe_irq_off(mask);
461 static void ucb1x00_release(struct device *dev)
463 struct ucb1x00 *ucb = classdev_to_ucb1x00(dev);
467 static struct class ucb1x00_class = {
469 .dev_release = ucb1x00_release,
472 static int ucb1x00_probe(struct mcp *mcp)
475 struct ucb1x00_driver *drv;
480 id = mcp_reg_read(mcp, UCB_ID);
482 if (id != UCB_ID_1200 && id != UCB_ID_1300 && id != UCB_ID_TC35143) {
483 printk(KERN_WARNING "UCB1x00 ID not found: %04x\n", id);
487 ucb = kzalloc(sizeof(struct ucb1x00), GFP_KERNEL);
493 ucb->dev.class = &ucb1x00_class;
494 ucb->dev.parent = &mcp->attached_device;
495 dev_set_name(&ucb->dev, "ucb1x00");
497 spin_lock_init(&ucb->lock);
498 spin_lock_init(&ucb->io_lock);
499 sema_init(&ucb->adc_sem, 1);
503 ucb->irq = ucb1x00_detect_irq(ucb);
504 if (ucb->irq == NO_IRQ) {
505 printk(KERN_ERR "UCB1x00: IRQ probe failed\n");
510 ret = request_irq(ucb->irq, ucb1x00_irq, IRQF_TRIGGER_RISING,
513 printk(KERN_ERR "ucb1x00: unable to grab irq%d: %d\n",
518 mcp_set_drvdata(mcp, ucb);
520 ret = device_register(&ucb->dev);
524 INIT_LIST_HEAD(&ucb->devs);
525 mutex_lock(&ucb1x00_mutex);
526 list_add(&ucb->node, &ucb1x00_devices);
527 list_for_each_entry(drv, &ucb1x00_drivers, node) {
528 ucb1x00_add_dev(ucb, drv);
530 mutex_unlock(&ucb1x00_mutex);
534 free_irq(ucb->irq, ucb);
543 static void ucb1x00_remove(struct mcp *mcp)
545 struct ucb1x00 *ucb = mcp_get_drvdata(mcp);
546 struct list_head *l, *n;
548 mutex_lock(&ucb1x00_mutex);
549 list_del(&ucb->node);
550 list_for_each_safe(l, n, &ucb->devs) {
551 struct ucb1x00_dev *dev = list_entry(l, struct ucb1x00_dev, dev_node);
552 ucb1x00_remove_dev(dev);
554 mutex_unlock(&ucb1x00_mutex);
556 free_irq(ucb->irq, ucb);
557 device_unregister(&ucb->dev);
560 int ucb1x00_register_driver(struct ucb1x00_driver *drv)
564 INIT_LIST_HEAD(&drv->devs);
565 mutex_lock(&ucb1x00_mutex);
566 list_add(&drv->node, &ucb1x00_drivers);
567 list_for_each_entry(ucb, &ucb1x00_devices, node) {
568 ucb1x00_add_dev(ucb, drv);
570 mutex_unlock(&ucb1x00_mutex);
574 void ucb1x00_unregister_driver(struct ucb1x00_driver *drv)
576 struct list_head *n, *l;
578 mutex_lock(&ucb1x00_mutex);
579 list_del(&drv->node);
580 list_for_each_safe(l, n, &drv->devs) {
581 struct ucb1x00_dev *dev = list_entry(l, struct ucb1x00_dev, drv_node);
582 ucb1x00_remove_dev(dev);
584 mutex_unlock(&ucb1x00_mutex);
587 static int ucb1x00_suspend(struct mcp *mcp, pm_message_t state)
589 struct ucb1x00 *ucb = mcp_get_drvdata(mcp);
590 struct ucb1x00_dev *dev;
592 mutex_lock(&ucb1x00_mutex);
593 list_for_each_entry(dev, &ucb->devs, dev_node) {
594 if (dev->drv->suspend)
595 dev->drv->suspend(dev, state);
597 mutex_unlock(&ucb1x00_mutex);
601 static int ucb1x00_resume(struct mcp *mcp)
603 struct ucb1x00 *ucb = mcp_get_drvdata(mcp);
604 struct ucb1x00_dev *dev;
606 mutex_lock(&ucb1x00_mutex);
607 list_for_each_entry(dev, &ucb->devs, dev_node) {
608 if (dev->drv->resume)
609 dev->drv->resume(dev);
611 mutex_unlock(&ucb1x00_mutex);
615 static struct mcp_driver ucb1x00_driver = {
619 .probe = ucb1x00_probe,
620 .remove = ucb1x00_remove,
621 .suspend = ucb1x00_suspend,
622 .resume = ucb1x00_resume,
625 static int __init ucb1x00_init(void)
627 int ret = class_register(&ucb1x00_class);
629 ret = mcp_driver_register(&ucb1x00_driver);
631 class_unregister(&ucb1x00_class);
636 static void __exit ucb1x00_exit(void)
638 mcp_driver_unregister(&ucb1x00_driver);
639 class_unregister(&ucb1x00_class);
642 module_init(ucb1x00_init);
643 module_exit(ucb1x00_exit);
645 EXPORT_SYMBOL(ucb1x00_io_set_dir);
646 EXPORT_SYMBOL(ucb1x00_io_write);
647 EXPORT_SYMBOL(ucb1x00_io_read);
649 EXPORT_SYMBOL(ucb1x00_adc_enable);
650 EXPORT_SYMBOL(ucb1x00_adc_read);
651 EXPORT_SYMBOL(ucb1x00_adc_disable);
653 EXPORT_SYMBOL(ucb1x00_hook_irq);
654 EXPORT_SYMBOL(ucb1x00_free_irq);
655 EXPORT_SYMBOL(ucb1x00_enable_irq);
656 EXPORT_SYMBOL(ucb1x00_disable_irq);
658 EXPORT_SYMBOL(ucb1x00_register_driver);
659 EXPORT_SYMBOL(ucb1x00_unregister_driver);
661 MODULE_AUTHOR("Russell King <rmk@arm.linux.org.uk>");
662 MODULE_DESCRIPTION("UCB1x00 core driver");
663 MODULE_LICENSE("GPL");