asic3: platform_get_irq() may return signed unnoticed
[safe/jmp/linux-2.6] / drivers / mfd / asic3.c
1 /*
2  * driver/mfd/asic3.c
3  *
4  * Compaq ASIC3 support.
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 version 2 as
8  * published by the Free Software Foundation.
9  *
10  * Copyright 2001 Compaq Computer Corporation.
11  * Copyright 2004-2005 Phil Blundell
12  * Copyright 2007-2008 OpenedHand Ltd.
13  *
14  * Authors: Phil Blundell <pb@handhelds.org>,
15  *          Samuel Ortiz <sameo@openedhand.com>
16  *
17  */
18
19 #include <linux/version.h>
20 #include <linux/kernel.h>
21 #include <linux/irq.h>
22 #include <linux/gpio.h>
23 #include <linux/io.h>
24 #include <linux/spinlock.h>
25 #include <linux/platform_device.h>
26
27 #include <linux/mfd/asic3.h>
28
29 struct asic3 {
30         void __iomem *mapping;
31         unsigned int bus_shift;
32         unsigned int irq_nr;
33         unsigned int irq_base;
34         spinlock_t lock;
35         u16 irq_bothedge[4];
36         struct gpio_chip gpio;
37         struct device *dev;
38 };
39
40 static int asic3_gpio_get(struct gpio_chip *chip, unsigned offset);
41
42 static inline void asic3_write_register(struct asic3 *asic,
43                                  unsigned int reg, u32 value)
44 {
45         iowrite16(value, asic->mapping +
46                   (reg >> asic->bus_shift));
47 }
48
49 static inline u32 asic3_read_register(struct asic3 *asic,
50                                unsigned int reg)
51 {
52         return ioread16(asic->mapping +
53                         (reg >> asic->bus_shift));
54 }
55
56 /* IRQs */
57 #define MAX_ASIC_ISR_LOOPS    20
58 #define ASIC3_GPIO_BASE_INCR \
59         (ASIC3_GPIO_B_BASE - ASIC3_GPIO_A_BASE)
60
61 static void asic3_irq_flip_edge(struct asic3 *asic,
62                                 u32 base, int bit)
63 {
64         u16 edge;
65         unsigned long flags;
66
67         spin_lock_irqsave(&asic->lock, flags);
68         edge = asic3_read_register(asic,
69                                    base + ASIC3_GPIO_EDGE_TRIGGER);
70         edge ^= bit;
71         asic3_write_register(asic,
72                              base + ASIC3_GPIO_EDGE_TRIGGER, edge);
73         spin_unlock_irqrestore(&asic->lock, flags);
74 }
75
76 static void asic3_irq_demux(unsigned int irq, struct irq_desc *desc)
77 {
78         int iter, i;
79         unsigned long flags;
80         struct asic3 *asic;
81
82         desc->chip->ack(irq);
83
84         asic = desc->handler_data;
85
86         for (iter = 0 ; iter < MAX_ASIC_ISR_LOOPS; iter++) {
87                 u32 status;
88                 int bank;
89
90                 spin_lock_irqsave(&asic->lock, flags);
91                 status = asic3_read_register(asic,
92                                              ASIC3_OFFSET(INTR, P_INT_STAT));
93                 spin_unlock_irqrestore(&asic->lock, flags);
94
95                 /* Check all ten register bits */
96                 if ((status & 0x3ff) == 0)
97                         break;
98
99                 /* Handle GPIO IRQs */
100                 for (bank = 0; bank < ASIC3_NUM_GPIO_BANKS; bank++) {
101                         if (status & (1 << bank)) {
102                                 unsigned long base, istat;
103
104                                 base = ASIC3_GPIO_A_BASE
105                                        + bank * ASIC3_GPIO_BASE_INCR;
106
107                                 spin_lock_irqsave(&asic->lock, flags);
108                                 istat = asic3_read_register(asic,
109                                                             base +
110                                                             ASIC3_GPIO_INT_STATUS);
111                                 /* Clearing IntStatus */
112                                 asic3_write_register(asic,
113                                                      base +
114                                                      ASIC3_GPIO_INT_STATUS, 0);
115                                 spin_unlock_irqrestore(&asic->lock, flags);
116
117                                 for (i = 0; i < ASIC3_GPIOS_PER_BANK; i++) {
118                                         int bit = (1 << i);
119                                         unsigned int irqnr;
120
121                                         if (!(istat & bit))
122                                                 continue;
123
124                                         irqnr = asic->irq_base +
125                                                 (ASIC3_GPIOS_PER_BANK * bank)
126                                                 + i;
127                                         desc = irq_desc + irqnr;
128                                         desc->handle_irq(irqnr, desc);
129                                         if (asic->irq_bothedge[bank] & bit)
130                                                 asic3_irq_flip_edge(asic, base,
131                                                                     bit);
132                                 }
133                         }
134                 }
135
136                 /* Handle remaining IRQs in the status register */
137                 for (i = ASIC3_NUM_GPIOS; i < ASIC3_NR_IRQS; i++) {
138                         /* They start at bit 4 and go up */
139                         if (status & (1 << (i - ASIC3_NUM_GPIOS + 4))) {
140                                 desc = irq_desc + asic->irq_base + i;
141                                 desc->handle_irq(asic->irq_base + i,
142                                                  desc);
143                         }
144                 }
145         }
146
147         if (iter >= MAX_ASIC_ISR_LOOPS)
148                 dev_err(asic->dev, "interrupt processing overrun\n");
149 }
150
151 static inline int asic3_irq_to_bank(struct asic3 *asic, int irq)
152 {
153         int n;
154
155         n = (irq - asic->irq_base) >> 4;
156
157         return (n * (ASIC3_GPIO_B_BASE - ASIC3_GPIO_A_BASE));
158 }
159
160 static inline int asic3_irq_to_index(struct asic3 *asic, int irq)
161 {
162         return (irq - asic->irq_base) & 0xf;
163 }
164
165 static void asic3_mask_gpio_irq(unsigned int irq)
166 {
167         struct asic3 *asic = get_irq_chip_data(irq);
168         u32 val, bank, index;
169         unsigned long flags;
170
171         bank = asic3_irq_to_bank(asic, irq);
172         index = asic3_irq_to_index(asic, irq);
173
174         spin_lock_irqsave(&asic->lock, flags);
175         val = asic3_read_register(asic, bank + ASIC3_GPIO_MASK);
176         val |= 1 << index;
177         asic3_write_register(asic, bank + ASIC3_GPIO_MASK, val);
178         spin_unlock_irqrestore(&asic->lock, flags);
179 }
180
181 static void asic3_mask_irq(unsigned int irq)
182 {
183         struct asic3 *asic = get_irq_chip_data(irq);
184         int regval;
185         unsigned long flags;
186
187         spin_lock_irqsave(&asic->lock, flags);
188         regval = asic3_read_register(asic,
189                                      ASIC3_INTR_BASE +
190                                      ASIC3_INTR_INT_MASK);
191
192         regval &= ~(ASIC3_INTMASK_MASK0 <<
193                     (irq - (asic->irq_base + ASIC3_NUM_GPIOS)));
194
195         asic3_write_register(asic,
196                              ASIC3_INTR_BASE +
197                              ASIC3_INTR_INT_MASK,
198                              regval);
199         spin_unlock_irqrestore(&asic->lock, flags);
200 }
201
202 static void asic3_unmask_gpio_irq(unsigned int irq)
203 {
204         struct asic3 *asic = get_irq_chip_data(irq);
205         u32 val, bank, index;
206         unsigned long flags;
207
208         bank = asic3_irq_to_bank(asic, irq);
209         index = asic3_irq_to_index(asic, irq);
210
211         spin_lock_irqsave(&asic->lock, flags);
212         val = asic3_read_register(asic, bank + ASIC3_GPIO_MASK);
213         val &= ~(1 << index);
214         asic3_write_register(asic, bank + ASIC3_GPIO_MASK, val);
215         spin_unlock_irqrestore(&asic->lock, flags);
216 }
217
218 static void asic3_unmask_irq(unsigned int irq)
219 {
220         struct asic3 *asic = get_irq_chip_data(irq);
221         int regval;
222         unsigned long flags;
223
224         spin_lock_irqsave(&asic->lock, flags);
225         regval = asic3_read_register(asic,
226                                      ASIC3_INTR_BASE +
227                                      ASIC3_INTR_INT_MASK);
228
229         regval |= (ASIC3_INTMASK_MASK0 <<
230                    (irq - (asic->irq_base + ASIC3_NUM_GPIOS)));
231
232         asic3_write_register(asic,
233                              ASIC3_INTR_BASE +
234                              ASIC3_INTR_INT_MASK,
235                              regval);
236         spin_unlock_irqrestore(&asic->lock, flags);
237 }
238
239 static int asic3_gpio_irq_type(unsigned int irq, unsigned int type)
240 {
241         struct asic3 *asic = get_irq_chip_data(irq);
242         u32 bank, index;
243         u16 trigger, level, edge, bit;
244         unsigned long flags;
245
246         bank = asic3_irq_to_bank(asic, irq);
247         index = asic3_irq_to_index(asic, irq);
248         bit = 1<<index;
249
250         spin_lock_irqsave(&asic->lock, flags);
251         level = asic3_read_register(asic,
252                                     bank + ASIC3_GPIO_LEVEL_TRIGGER);
253         edge = asic3_read_register(asic,
254                                    bank + ASIC3_GPIO_EDGE_TRIGGER);
255         trigger = asic3_read_register(asic,
256                                       bank + ASIC3_GPIO_TRIGGER_TYPE);
257         asic->irq_bothedge[(irq - asic->irq_base) >> 4] &= ~bit;
258
259         if (type == IRQT_RISING) {
260                 trigger |= bit;
261                 edge |= bit;
262         } else if (type == IRQT_FALLING) {
263                 trigger |= bit;
264                 edge &= ~bit;
265         } else if (type == IRQT_BOTHEDGE) {
266                 trigger |= bit;
267                 if (asic3_gpio_get(&asic->gpio, irq - asic->irq_base))
268                         edge &= ~bit;
269                 else
270                         edge |= bit;
271                 asic->irq_bothedge[(irq - asic->irq_base) >> 4] |= bit;
272         } else if (type == IRQT_LOW) {
273                 trigger &= ~bit;
274                 level &= ~bit;
275         } else if (type == IRQT_HIGH) {
276                 trigger &= ~bit;
277                 level |= bit;
278         } else {
279                 /*
280                  * if type == IRQT_NOEDGE, we should mask interrupts, but
281                  * be careful to not unmask them if mask was also called.
282                  * Probably need internal state for mask.
283                  */
284                 dev_notice(asic->dev, "irq type not changed\n");
285         }
286         asic3_write_register(asic, bank + ASIC3_GPIO_LEVEL_TRIGGER,
287                              level);
288         asic3_write_register(asic, bank + ASIC3_GPIO_EDGE_TRIGGER,
289                              edge);
290         asic3_write_register(asic, bank + ASIC3_GPIO_TRIGGER_TYPE,
291                              trigger);
292         spin_unlock_irqrestore(&asic->lock, flags);
293         return 0;
294 }
295
296 static struct irq_chip asic3_gpio_irq_chip = {
297         .name           = "ASIC3-GPIO",
298         .ack            = asic3_mask_gpio_irq,
299         .mask           = asic3_mask_gpio_irq,
300         .unmask         = asic3_unmask_gpio_irq,
301         .set_type       = asic3_gpio_irq_type,
302 };
303
304 static struct irq_chip asic3_irq_chip = {
305         .name           = "ASIC3",
306         .ack            = asic3_mask_irq,
307         .mask           = asic3_mask_irq,
308         .unmask         = asic3_unmask_irq,
309 };
310
311 static int __init asic3_irq_probe(struct platform_device *pdev)
312 {
313         struct asic3 *asic = platform_get_drvdata(pdev);
314         unsigned long clksel = 0;
315         unsigned int irq, irq_base;
316         int map_size;
317         int ret;
318
319         ret = platform_get_irq(pdev, 0);
320         if (ret < 0)
321                 return ret;
322         asic->irq_nr = ret;
323
324         /* turn on clock to IRQ controller */
325         clksel |= CLOCK_SEL_CX;
326         asic3_write_register(asic, ASIC3_OFFSET(CLOCK, SEL),
327                              clksel);
328
329         irq_base = asic->irq_base;
330
331         for (irq = irq_base; irq < irq_base + ASIC3_NR_IRQS; irq++) {
332                 if (irq < asic->irq_base + ASIC3_NUM_GPIOS)
333                         set_irq_chip(irq, &asic3_gpio_irq_chip);
334                 else
335                         set_irq_chip(irq, &asic3_irq_chip);
336
337                 set_irq_chip_data(irq, asic);
338                 set_irq_handler(irq, handle_level_irq);
339                 set_irq_flags(irq, IRQF_VALID | IRQF_PROBE);
340         }
341
342         asic3_write_register(asic, ASIC3_OFFSET(INTR, INT_MASK),
343                              ASIC3_INTMASK_GINTMASK);
344
345         set_irq_chained_handler(asic->irq_nr, asic3_irq_demux);
346         set_irq_type(asic->irq_nr, IRQT_RISING);
347         set_irq_data(asic->irq_nr, asic);
348
349         return 0;
350 }
351
352 static void asic3_irq_remove(struct platform_device *pdev)
353 {
354         struct asic3 *asic = platform_get_drvdata(pdev);
355         unsigned int irq, irq_base;
356
357         irq_base = asic->irq_base;
358
359         for (irq = irq_base; irq < irq_base + ASIC3_NR_IRQS; irq++) {
360                 set_irq_flags(irq, 0);
361                 set_irq_handler(irq, NULL);
362                 set_irq_chip(irq, NULL);
363                 set_irq_chip_data(irq, NULL);
364         }
365         set_irq_chained_handler(asic->irq_nr, NULL);
366 }
367
368 /* GPIOs */
369 static int asic3_gpio_direction(struct gpio_chip *chip,
370                                 unsigned offset, int out)
371 {
372         u32 mask = ASIC3_GPIO_TO_MASK(offset), out_reg;
373         unsigned int gpio_base;
374         unsigned long flags;
375         struct asic3 *asic;
376
377         asic = container_of(chip, struct asic3, gpio);
378         gpio_base = ASIC3_GPIO_TO_BASE(offset);
379
380         if (gpio_base > ASIC3_GPIO_D_BASE) {
381                 dev_err(asic->dev, "Invalid base (0x%x) for gpio %d\n",
382                         gpio_base, offset);
383                 return -EINVAL;
384         }
385
386         spin_lock_irqsave(&asic->lock, flags);
387
388         out_reg = asic3_read_register(asic, gpio_base + ASIC3_GPIO_DIRECTION);
389
390         /* Input is 0, Output is 1 */
391         if (out)
392                 out_reg |= mask;
393         else
394                 out_reg &= ~mask;
395
396         asic3_write_register(asic, gpio_base + ASIC3_GPIO_DIRECTION, out_reg);
397
398         spin_unlock_irqrestore(&asic->lock, flags);
399
400         return 0;
401
402 }
403
404 static int asic3_gpio_direction_input(struct gpio_chip *chip,
405                                       unsigned offset)
406 {
407         return asic3_gpio_direction(chip, offset, 0);
408 }
409
410 static int asic3_gpio_direction_output(struct gpio_chip *chip,
411                                        unsigned offset, int value)
412 {
413         return asic3_gpio_direction(chip, offset, 1);
414 }
415
416 static int asic3_gpio_get(struct gpio_chip *chip,
417                           unsigned offset)
418 {
419         unsigned int gpio_base;
420         u32 mask = ASIC3_GPIO_TO_MASK(offset);
421         struct asic3 *asic;
422
423         asic = container_of(chip, struct asic3, gpio);
424         gpio_base = ASIC3_GPIO_TO_BASE(offset);
425
426         if (gpio_base > ASIC3_GPIO_D_BASE) {
427                 dev_err(asic->dev, "Invalid base (0x%x) for gpio %d\n",
428                         gpio_base, offset);
429                 return -EINVAL;
430         }
431
432         return asic3_read_register(asic, gpio_base + ASIC3_GPIO_STATUS) & mask;
433 }
434
435 static void asic3_gpio_set(struct gpio_chip *chip,
436                            unsigned offset, int value)
437 {
438         u32 mask, out_reg;
439         unsigned int gpio_base;
440         unsigned long flags;
441         struct asic3 *asic;
442
443         asic = container_of(chip, struct asic3, gpio);
444         gpio_base = ASIC3_GPIO_TO_BASE(offset);
445
446         if (gpio_base > ASIC3_GPIO_D_BASE) {
447                 dev_err(asic->dev, "Invalid base (0x%x) for gpio %d\n",
448                         gpio_base, offset);
449                 return;
450         }
451
452         mask = ASIC3_GPIO_TO_MASK(offset);
453
454         spin_lock_irqsave(&asic->lock, flags);
455
456         out_reg = asic3_read_register(asic, gpio_base + ASIC3_GPIO_OUT);
457
458         if (value)
459                 out_reg |= mask;
460         else
461                 out_reg &= ~mask;
462
463         asic3_write_register(asic, gpio_base + ASIC3_GPIO_OUT, out_reg);
464
465         spin_unlock_irqrestore(&asic->lock, flags);
466
467         return;
468 }
469
470 static __init int asic3_gpio_probe(struct platform_device *pdev,
471                                    u16 *gpio_config, int num)
472 {
473         struct asic3 *asic = platform_get_drvdata(pdev);
474         u16 alt_reg[ASIC3_NUM_GPIO_BANKS];
475         u16 out_reg[ASIC3_NUM_GPIO_BANKS];
476         u16 dir_reg[ASIC3_NUM_GPIO_BANKS];
477         int i;
478
479         memzero(alt_reg, ASIC3_NUM_GPIO_BANKS * sizeof(u16));
480         memzero(out_reg, ASIC3_NUM_GPIO_BANKS * sizeof(u16));
481         memzero(dir_reg, ASIC3_NUM_GPIO_BANKS * sizeof(u16));
482
483         /* Enable all GPIOs */
484         asic3_write_register(asic, ASIC3_GPIO_OFFSET(A, MASK), 0xffff);
485         asic3_write_register(asic, ASIC3_GPIO_OFFSET(B, MASK), 0xffff);
486         asic3_write_register(asic, ASIC3_GPIO_OFFSET(C, MASK), 0xffff);
487         asic3_write_register(asic, ASIC3_GPIO_OFFSET(D, MASK), 0xffff);
488
489         for (i = 0; i < num; i++) {
490                 u8 alt, pin, dir, init, bank_num, bit_num;
491                 u16 config = gpio_config[i];
492
493                 pin = ASIC3_CONFIG_GPIO_PIN(config);
494                 alt = ASIC3_CONFIG_GPIO_ALT(config);
495                 dir = ASIC3_CONFIG_GPIO_DIR(config);
496                 init = ASIC3_CONFIG_GPIO_INIT(config);
497
498                 bank_num = ASIC3_GPIO_TO_BANK(pin);
499                 bit_num = ASIC3_GPIO_TO_BIT(pin);
500
501                 alt_reg[bank_num] |= (alt << bit_num);
502                 out_reg[bank_num] |= (init << bit_num);
503                 dir_reg[bank_num] |= (dir << bit_num);
504         }
505
506         for (i = 0; i < ASIC3_NUM_GPIO_BANKS; i++) {
507                 asic3_write_register(asic,
508                                      ASIC3_BANK_TO_BASE(i) +
509                                      ASIC3_GPIO_DIRECTION,
510                                      dir_reg[i]);
511                 asic3_write_register(asic,
512                                      ASIC3_BANK_TO_BASE(i) + ASIC3_GPIO_OUT,
513                                      out_reg[i]);
514                 asic3_write_register(asic,
515                                      ASIC3_BANK_TO_BASE(i) +
516                                      ASIC3_GPIO_ALT_FUNCTION,
517                                      alt_reg[i]);
518         }
519
520         return gpiochip_add(&asic->gpio);
521 }
522
523 static int asic3_gpio_remove(struct platform_device *pdev)
524 {
525         struct asic3 *asic = platform_get_drvdata(pdev);
526
527         return gpiochip_remove(&asic->gpio);
528 }
529
530
531 /* Core */
532 static int __init asic3_probe(struct platform_device *pdev)
533 {
534         struct asic3_platform_data *pdata = pdev->dev.platform_data;
535         struct asic3 *asic;
536         struct resource *mem;
537         unsigned long clksel;
538         int ret = 0;
539
540         asic = kzalloc(sizeof(struct asic3), GFP_KERNEL);
541         if (asic == NULL) {
542                 printk(KERN_ERR "kzalloc failed\n");
543                 return -ENOMEM;
544         }
545
546         spin_lock_init(&asic->lock);
547         platform_set_drvdata(pdev, asic);
548         asic->dev = &pdev->dev;
549
550         mem = platform_get_resource(pdev, IORESOURCE_MEM, 0);
551         if (!mem) {
552                 ret = -ENOMEM;
553                 dev_err(asic->dev, "no MEM resource\n");
554                 goto out_free;
555         }
556
557         map_size = mem->end - mem->start + 1;
558         asic->mapping = ioremap(mem->start, map_size);
559         if (!asic->mapping) {
560                 ret = -ENOMEM;
561                 dev_err(asic->dev, "Couldn't ioremap\n");
562                 goto out_free;
563         }
564
565         asic->irq_base = pdata->irq_base;
566
567         /* calculate bus shift from mem resource */
568         asic->bus_shift = 2 - (map_size >> 12);
569
570         clksel = 0;
571         asic3_write_register(asic, ASIC3_OFFSET(CLOCK, SEL), clksel);
572
573         ret = asic3_irq_probe(pdev);
574         if (ret < 0) {
575                 dev_err(asic->dev, "Couldn't probe IRQs\n");
576                 goto out_unmap;
577         }
578
579         asic->gpio.base = pdata->gpio_base;
580         asic->gpio.ngpio = ASIC3_NUM_GPIOS;
581         asic->gpio.get = asic3_gpio_get;
582         asic->gpio.set = asic3_gpio_set;
583         asic->gpio.direction_input = asic3_gpio_direction_input;
584         asic->gpio.direction_output = asic3_gpio_direction_output;
585
586         ret = asic3_gpio_probe(pdev,
587                                pdata->gpio_config,
588                                pdata->gpio_config_num);
589         if (ret < 0) {
590                 dev_err(asic->dev, "GPIO probe failed\n");
591                 goto out_irq;
592         }
593
594         dev_info(asic->dev, "ASIC3 Core driver\n");
595
596         return 0;
597
598  out_irq:
599         asic3_irq_remove(pdev);
600
601  out_unmap:
602         iounmap(asic->mapping);
603
604  out_free:
605         kfree(asic);
606
607         return ret;
608 }
609
610 static int asic3_remove(struct platform_device *pdev)
611 {
612         int ret;
613         struct asic3 *asic = platform_get_drvdata(pdev);
614
615         ret = asic3_gpio_remove(pdev);
616         if (ret < 0)
617                 return ret;
618         asic3_irq_remove(pdev);
619
620         asic3_write_register(asic, ASIC3_OFFSET(CLOCK, SEL), 0);
621
622         iounmap(asic->mapping);
623
624         kfree(asic);
625
626         return 0;
627 }
628
629 static void asic3_shutdown(struct platform_device *pdev)
630 {
631 }
632
633 static struct platform_driver asic3_device_driver = {
634         .driver         = {
635                 .name   = "asic3",
636         },
637         .remove         = __devexit_p(asic3_remove),
638         .shutdown       = asic3_shutdown,
639 };
640
641 static int __init asic3_init(void)
642 {
643         int retval = 0;
644         retval = platform_driver_probe(&asic3_device_driver, asic3_probe);
645         return retval;
646 }
647
648 subsys_initcall(asic3_init);