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n_tty: Reduce branching in canon_copy_from_read_buf()
[linux/fpc-iii.git] / drivers / gpio / gpio-tz1090.c
blob87bb1b1eee8deacaa4f9cdb9ccc81166025393e5
1 /*
2 * Toumaz Xenif TZ1090 GPIO handling.
3 *
4 * Copyright (C) 2008-2013 Imagination Technologies Ltd.
5 *
6 * Based on ARM PXA code and others.
7 *
8 * This program is free software; you can redistribute it and/or modify
9 * it under the terms of the GNU General Public License version 2 as
10 * published by the Free Software Foundation.
11 */
12
13 #include <linux/bitops.h>
14 #include <linux/export.h>
15 #include <linux/gpio.h>
16 #include <linux/interrupt.h>
17 #include <linux/io.h>
18 #include <linux/irq.h>
19 #include <linux/irqdomain.h>
20 #include <linux/kernel.h>
21 #include <linux/of_irq.h>
22 #include <linux/pinctrl/consumer.h>
23 #include <linux/platform_device.h>
24 #include <linux/slab.h>
25 #include <linux/syscore_ops.h>
26 #include <asm/global_lock.h>
27
28 /* Register offsets from bank base address */
29 #define REG_GPIO_DIR 0x00
30 #define REG_GPIO_IRQ_PLRT 0x20
31 #define REG_GPIO_IRQ_TYPE 0x30
32 #define REG_GPIO_IRQ_EN 0x40
33 #define REG_GPIO_IRQ_STS 0x50
34 #define REG_GPIO_BIT_EN 0x60
35 #define REG_GPIO_DIN 0x70
36 #define REG_GPIO_DOUT 0x80
37
38 /* REG_GPIO_IRQ_PLRT */
39 #define REG_GPIO_IRQ_PLRT_LOW 0
40 #define REG_GPIO_IRQ_PLRT_HIGH 1
41
42 /* REG_GPIO_IRQ_TYPE */
43 #define REG_GPIO_IRQ_TYPE_LEVEL 0
44 #define REG_GPIO_IRQ_TYPE_EDGE 1
45
46 /**
47 * struct tz1090_gpio_bank - GPIO bank private data
48 * @chip: Generic GPIO chip for GPIO bank
49 * @domain: IRQ domain for GPIO bank (may be NULL)
50 * @reg: Base of registers, offset for this GPIO bank
51 * @irq: IRQ number for GPIO bank
52 * @label: Debug GPIO bank label, used for storage of chip->label
53 *
54 * This is the main private data for a GPIO bank. It encapsulates a gpio_chip,
55 * and the callbacks for the gpio_chip can access the private data with the
56 * to_bank() macro below.
57 */
58 struct tz1090_gpio_bank {
59 struct gpio_chip chip;
60 struct irq_domain *domain;
61 void __iomem *reg;
62 int irq;
63 char label[16];
64 };
65 #define to_bank(c) container_of(c, struct tz1090_gpio_bank, chip)
66
67 /**
68 * struct tz1090_gpio - Overall GPIO device private data
69 * @dev: Device (from platform device)
70 * @reg: Base of GPIO registers
71 *
72 * Represents the overall GPIO device. This structure is actually only
73 * temporary, and used during init.
74 */
75 struct tz1090_gpio {
76 struct device *dev;
77 void __iomem *reg;
78 };
79
80 /**
81 * struct tz1090_gpio_bank_info - Temporary registration info for GPIO bank
82 * @priv: Overall GPIO device private data
83 * @node: Device tree node specific to this GPIO bank
84 * @index: Index of bank in range 0-2
85 */
86 struct tz1090_gpio_bank_info {
87 struct tz1090_gpio *priv;
88 struct device_node *node;
89 unsigned int index;
90 };
91
92 /* Convenience register accessors */
93 static inline void tz1090_gpio_write(struct tz1090_gpio_bank *bank,
94 unsigned int reg_offs, u32 data)
95 {
96 iowrite32(data, bank->reg + reg_offs);
97 }
98
99 static inline u32 tz1090_gpio_read(struct tz1090_gpio_bank *bank,
100 unsigned int reg_offs)
101 {
102 return ioread32(bank->reg + reg_offs);
103 }
104
105 /* caller must hold LOCK2 */
106 static inline void _tz1090_gpio_clear_bit(struct tz1090_gpio_bank *bank,
107 unsigned int reg_offs,
108 unsigned int offset)
109 {
110 u32 value;
111
112 value = tz1090_gpio_read(bank, reg_offs);
113 value &= ~BIT(offset);
114 tz1090_gpio_write(bank, reg_offs, value);
115 }
116
117 static void tz1090_gpio_clear_bit(struct tz1090_gpio_bank *bank,
118 unsigned int reg_offs,
119 unsigned int offset)
120 {
121 int lstat;
122
123 __global_lock2(lstat);
124 _tz1090_gpio_clear_bit(bank, reg_offs, offset);
125 __global_unlock2(lstat);
126 }
127
128 /* caller must hold LOCK2 */
129 static inline void _tz1090_gpio_set_bit(struct tz1090_gpio_bank *bank,
130 unsigned int reg_offs,
131 unsigned int offset)
132 {
133 u32 value;
134
135 value = tz1090_gpio_read(bank, reg_offs);
136 value |= BIT(offset);
137 tz1090_gpio_write(bank, reg_offs, value);
138 }
139
140 static void tz1090_gpio_set_bit(struct tz1090_gpio_bank *bank,
141 unsigned int reg_offs,
142 unsigned int offset)
143 {
144 int lstat;
145
146 __global_lock2(lstat);
147 _tz1090_gpio_set_bit(bank, reg_offs, offset);
148 __global_unlock2(lstat);
149 }
150
151 /* caller must hold LOCK2 */
152 static inline void _tz1090_gpio_mod_bit(struct tz1090_gpio_bank *bank,
153 unsigned int reg_offs,
154 unsigned int offset,
155 bool val)
156 {
157 u32 value;
158
159 value = tz1090_gpio_read(bank, reg_offs);
160 value &= ~BIT(offset);
161 if (val)
162 value |= BIT(offset);
163 tz1090_gpio_write(bank, reg_offs, value);
164 }
165
166 static void tz1090_gpio_mod_bit(struct tz1090_gpio_bank *bank,
167 unsigned int reg_offs,
168 unsigned int offset,
169 bool val)
170 {
171 int lstat;
172
173 __global_lock2(lstat);
174 _tz1090_gpio_mod_bit(bank, reg_offs, offset, val);
175 __global_unlock2(lstat);
176 }
177
178 static inline int tz1090_gpio_read_bit(struct tz1090_gpio_bank *bank,
179 unsigned int reg_offs,
180 unsigned int offset)
181 {
182 return tz1090_gpio_read(bank, reg_offs) & BIT(offset);
183 }
184
185 /* GPIO chip callbacks */
186
187 static int tz1090_gpio_direction_input(struct gpio_chip *chip,
188 unsigned int offset)
189 {
190 struct tz1090_gpio_bank *bank = to_bank(chip);
191 tz1090_gpio_set_bit(bank, REG_GPIO_DIR, offset);
192
193 return 0;
194 }
195
196 static int tz1090_gpio_direction_output(struct gpio_chip *chip,
197 unsigned int offset, int output_value)
198 {
199 struct tz1090_gpio_bank *bank = to_bank(chip);
200 int lstat;
201
202 __global_lock2(lstat);
203 _tz1090_gpio_mod_bit(bank, REG_GPIO_DOUT, offset, output_value);
204 _tz1090_gpio_clear_bit(bank, REG_GPIO_DIR, offset);
205 __global_unlock2(lstat);
206
207 return 0;
208 }
209
210 /*
211 * Return GPIO level
212 */
213 static int tz1090_gpio_get(struct gpio_chip *chip, unsigned int offset)
214 {
215 struct tz1090_gpio_bank *bank = to_bank(chip);
216
217 return tz1090_gpio_read_bit(bank, REG_GPIO_DIN, offset);
218 }
219
220 /*
221 * Set output GPIO level
222 */
223 static void tz1090_gpio_set(struct gpio_chip *chip, unsigned int offset,
224 int output_value)
225 {
226 struct tz1090_gpio_bank *bank = to_bank(chip);
227
228 tz1090_gpio_mod_bit(bank, REG_GPIO_DOUT, offset, output_value);
229 }
230
231 static int tz1090_gpio_request(struct gpio_chip *chip, unsigned int offset)
232 {
233 struct tz1090_gpio_bank *bank = to_bank(chip);
234 int ret;
235
236 ret = pinctrl_request_gpio(chip->base + offset);
237 if (ret)
238 return ret;
239
240 tz1090_gpio_set_bit(bank, REG_GPIO_DIR, offset);
241 tz1090_gpio_set_bit(bank, REG_GPIO_BIT_EN, offset);
242
243 return 0;
244 }
245
246 static void tz1090_gpio_free(struct gpio_chip *chip, unsigned int offset)
247 {
248 struct tz1090_gpio_bank *bank = to_bank(chip);
249
250 pinctrl_free_gpio(chip->base + offset);
251
252 tz1090_gpio_clear_bit(bank, REG_GPIO_BIT_EN, offset);
253 }
254
255 static int tz1090_gpio_to_irq(struct gpio_chip *chip, unsigned int offset)
256 {
257 struct tz1090_gpio_bank *bank = to_bank(chip);
258
259 if (!bank->domain)
260 return -EINVAL;
261
262 return irq_create_mapping(bank->domain, offset);
263 }
264
265 /* IRQ chip handlers */
266
267 /* Get TZ1090 GPIO chip from irq data provided to generic IRQ callbacks */
268 static inline struct tz1090_gpio_bank *irqd_to_gpio_bank(struct irq_data *data)
269 {
270 return (struct tz1090_gpio_bank *)data->domain->host_data;
271 }
272
273 static void tz1090_gpio_irq_polarity(struct tz1090_gpio_bank *bank,
274 unsigned int offset, unsigned int polarity)
275 {
276 tz1090_gpio_mod_bit(bank, REG_GPIO_IRQ_PLRT, offset, polarity);
277 }
278
279 static void tz1090_gpio_irq_type(struct tz1090_gpio_bank *bank,
280 unsigned int offset, unsigned int type)
281 {
282 tz1090_gpio_mod_bit(bank, REG_GPIO_IRQ_TYPE, offset, type);
283 }
284
285 /* set polarity to trigger on next edge, whether rising or falling */
286 static void tz1090_gpio_irq_next_edge(struct tz1090_gpio_bank *bank,
287 unsigned int offset)
288 {
289 unsigned int value_p, value_i;
290 int lstat;
291
292 /*
293 * Set the GPIO's interrupt polarity to the opposite of the current
294 * input value so that the next edge triggers an interrupt.
295 */
296 __global_lock2(lstat);
297 value_i = ~tz1090_gpio_read(bank, REG_GPIO_DIN);
298 value_p = tz1090_gpio_read(bank, REG_GPIO_IRQ_PLRT);
299 value_p &= ~BIT(offset);
300 value_p |= value_i & BIT(offset);
301 tz1090_gpio_write(bank, REG_GPIO_IRQ_PLRT, value_p);
302 __global_unlock2(lstat);
303 }
304
305 static unsigned int gpio_startup_irq(struct irq_data *data)
306 {
307 /*
308 * This warning indicates that the type of the irq hasn't been set
309 * before enabling the irq. This would normally be done by passing some
310 * trigger flags to request_irq().
311 */
312 WARN(irqd_get_trigger_type(data) == IRQ_TYPE_NONE,
313 "irq type not set before enabling gpio irq %d", data->irq);
314
315 irq_gc_ack_clr_bit(data);
316 irq_gc_mask_set_bit(data);
317 return 0;
318 }
319
320 static int gpio_set_irq_type(struct irq_data *data, unsigned int flow_type)
321 {
322 struct tz1090_gpio_bank *bank = irqd_to_gpio_bank(data);
323 unsigned int type;
324 unsigned int polarity;
325
326 switch (flow_type) {
327 case IRQ_TYPE_EDGE_BOTH:
328 type = REG_GPIO_IRQ_TYPE_EDGE;
329 polarity = REG_GPIO_IRQ_PLRT_LOW;
330 break;
331 case IRQ_TYPE_EDGE_RISING:
332 type = REG_GPIO_IRQ_TYPE_EDGE;
333 polarity = REG_GPIO_IRQ_PLRT_HIGH;
334 break;
335 case IRQ_TYPE_EDGE_FALLING:
336 type = REG_GPIO_IRQ_TYPE_EDGE;
337 polarity = REG_GPIO_IRQ_PLRT_LOW;
338 break;
339 case IRQ_TYPE_LEVEL_HIGH:
340 type = REG_GPIO_IRQ_TYPE_LEVEL;
341 polarity = REG_GPIO_IRQ_PLRT_HIGH;
342 break;
343 case IRQ_TYPE_LEVEL_LOW:
344 type = REG_GPIO_IRQ_TYPE_LEVEL;
345 polarity = REG_GPIO_IRQ_PLRT_LOW;
346 break;
347 default:
348 return -EINVAL;
349 }
350
351 tz1090_gpio_irq_type(bank, data->hwirq, type);
352 irq_setup_alt_chip(data, flow_type);
353
354 if (flow_type == IRQ_TYPE_EDGE_BOTH)
355 tz1090_gpio_irq_next_edge(bank, data->hwirq);
356 else
357 tz1090_gpio_irq_polarity(bank, data->hwirq, polarity);
358
359 return 0;
360 }
361
362 #ifdef CONFIG_SUSPEND
363 static int gpio_set_irq_wake(struct irq_data *data, unsigned int on)
364 {
365 struct tz1090_gpio_bank *bank = irqd_to_gpio_bank(data);
366
367 #ifdef CONFIG_PM_DEBUG
368 pr_info("irq_wake irq%d state:%d\n", data->irq, on);
369 #endif
370
371 /* wake on gpio block interrupt */
372 return irq_set_irq_wake(bank->irq, on);
373 }
374 #else
375 #define gpio_set_irq_wake NULL
376 #endif
377
378 static void tz1090_gpio_irq_handler(struct irq_desc *desc)
379 {
380 irq_hw_number_t hw;
381 unsigned int irq_stat, irq_no;
382 struct tz1090_gpio_bank *bank;
383 struct irq_desc *child_desc;
384
385 bank = (struct tz1090_gpio_bank *)irq_desc_get_handler_data(desc);
386 irq_stat = tz1090_gpio_read(bank, REG_GPIO_DIR) &
387 tz1090_gpio_read(bank, REG_GPIO_IRQ_STS) &
388 tz1090_gpio_read(bank, REG_GPIO_IRQ_EN) &
389 0x3FFFFFFF; /* 30 bits only */
390
391 for (hw = 0; irq_stat; irq_stat >>= 1, ++hw) {
392 if (!(irq_stat & 1))
393 continue;
394
395 irq_no = irq_linear_revmap(bank->domain, hw);
396 child_desc = irq_to_desc(irq_no);
397
398 /* Toggle edge for pin with both edges triggering enabled */
399 if (irqd_get_trigger_type(&child_desc->irq_data)
400 == IRQ_TYPE_EDGE_BOTH)
401 tz1090_gpio_irq_next_edge(bank, hw);
402
403 generic_handle_irq_desc(child_desc);
404 }
405 }
406
407 static int tz1090_gpio_bank_probe(struct tz1090_gpio_bank_info *info)
408 {
409 struct device_node *np = info->node;
410 struct device *dev = info->priv->dev;
411 struct tz1090_gpio_bank *bank;
412 struct irq_chip_generic *gc;
413 int err;
414
415 bank = devm_kzalloc(dev, sizeof(*bank), GFP_KERNEL);
416 if (!bank) {
417 dev_err(dev, "unable to allocate driver data\n");
418 return -ENOMEM;
419 }
420
421 /* Offset the main registers to the first register in this bank */
422 bank->reg = info->priv->reg + info->index * 4;
423
424 /* Set up GPIO chip */
425 snprintf(bank->label, sizeof(bank->label), "tz1090-gpio-%u",
426 info->index);
427 bank->chip.label = bank->label;
428 bank->chip.dev = dev;
429 bank->chip.direction_input = tz1090_gpio_direction_input;
430 bank->chip.direction_output = tz1090_gpio_direction_output;
431 bank->chip.get = tz1090_gpio_get;
432 bank->chip.set = tz1090_gpio_set;
433 bank->chip.free = tz1090_gpio_free;
434 bank->chip.request = tz1090_gpio_request;
435 bank->chip.to_irq = tz1090_gpio_to_irq;
436 bank->chip.of_node = np;
437
438 /* GPIO numbering from 0 */
439 bank->chip.base = info->index * 30;
440 bank->chip.ngpio = 30;
441
442 /* Add the GPIO bank */
443 gpiochip_add(&bank->chip);
444
445 /* Get the GPIO bank IRQ if provided */
446 bank->irq = irq_of_parse_and_map(np, 0);
447
448 /* The interrupt is optional (it may be used by another core on chip) */
449 if (!bank->irq) {
450 dev_info(dev, "IRQ not provided for bank %u, IRQs disabled\n",
451 info->index);
452 return 0;
453 }
454
455 dev_info(dev, "Setting up IRQs for GPIO bank %u\n",
456 info->index);
457
458 /*
459 * Initialise all interrupts to disabled so we don't get
460 * spurious ones on a dirty boot and hit the BUG_ON in the
461 * handler.
462 */
463 tz1090_gpio_write(bank, REG_GPIO_IRQ_EN, 0);
464
465 /* Add a virtual IRQ for each GPIO */
466 bank->domain = irq_domain_add_linear(np,
467 bank->chip.ngpio,
468 &irq_generic_chip_ops,
469 bank);
470
471 /* Set up a generic irq chip with 2 chip types (level and edge) */
472 err = irq_alloc_domain_generic_chips(bank->domain, bank->chip.ngpio, 2,
473 bank->label, handle_bad_irq, 0, 0,
474 IRQ_GC_INIT_NESTED_LOCK);
475 if (err) {
476 dev_info(dev,
477 "irq_alloc_domain_generic_chips failed for bank %u, IRQs disabled\n",
478 info->index);
479 irq_domain_remove(bank->domain);
480 return 0;
481 }
482
483 gc = irq_get_domain_generic_chip(bank->domain, 0);
484 gc->reg_base = bank->reg;
485
486 /* level chip type */
487 gc->chip_types[0].type = IRQ_TYPE_LEVEL_MASK;
488 gc->chip_types[0].handler = handle_level_irq;
489 gc->chip_types[0].regs.ack = REG_GPIO_IRQ_STS;
490 gc->chip_types[0].regs.mask = REG_GPIO_IRQ_EN;
491 gc->chip_types[0].chip.irq_startup = gpio_startup_irq;
492 gc->chip_types[0].chip.irq_ack = irq_gc_ack_clr_bit;
493 gc->chip_types[0].chip.irq_mask = irq_gc_mask_clr_bit;
494 gc->chip_types[0].chip.irq_unmask = irq_gc_mask_set_bit;
495 gc->chip_types[0].chip.irq_set_type = gpio_set_irq_type;
496 gc->chip_types[0].chip.irq_set_wake = gpio_set_irq_wake;
497 gc->chip_types[0].chip.flags = IRQCHIP_MASK_ON_SUSPEND;
498
499 /* edge chip type */
500 gc->chip_types[1].type = IRQ_TYPE_EDGE_BOTH;
501 gc->chip_types[1].handler = handle_edge_irq;
502 gc->chip_types[1].regs.ack = REG_GPIO_IRQ_STS;
503 gc->chip_types[1].regs.mask = REG_GPIO_IRQ_EN;
504 gc->chip_types[1].chip.irq_startup = gpio_startup_irq;
505 gc->chip_types[1].chip.irq_ack = irq_gc_ack_clr_bit;
506 gc->chip_types[1].chip.irq_mask = irq_gc_mask_clr_bit;
507 gc->chip_types[1].chip.irq_unmask = irq_gc_mask_set_bit;
508 gc->chip_types[1].chip.irq_set_type = gpio_set_irq_type;
509 gc->chip_types[1].chip.irq_set_wake = gpio_set_irq_wake;
510 gc->chip_types[1].chip.flags = IRQCHIP_MASK_ON_SUSPEND;
511
512 /* Setup chained handler for this GPIO bank */
513 irq_set_chained_handler_and_data(bank->irq, tz1090_gpio_irq_handler,
514 bank);
515
516 return 0;
517 }
518
519 static void tz1090_gpio_register_banks(struct tz1090_gpio *priv)
520 {
521 struct device_node *np = priv->dev->of_node;
522 struct device_node *node;
523
524 for_each_available_child_of_node(np, node) {
525 struct tz1090_gpio_bank_info info;
526 u32 addr;
527 int ret;
528
529 ret = of_property_read_u32(node, "reg", &addr);
530 if (ret) {
531 dev_err(priv->dev, "invalid reg on %s\n",
532 node->full_name);
533 continue;
534 }
535 if (addr >= 3) {
536 dev_err(priv->dev, "index %u in %s out of range\n",
537 addr, node->full_name);
538 continue;
539 }
540
541 info.index = addr;
542 info.node = of_node_get(node);
543 info.priv = priv;
544
545 ret = tz1090_gpio_bank_probe(&info);
546 if (ret) {
547 dev_err(priv->dev, "failure registering %s\n",
548 node->full_name);
549 of_node_put(node);
550 continue;
551 }
552 }
553 }
554
555 static int tz1090_gpio_probe(struct platform_device *pdev)
556 {
557 struct device_node *np = pdev->dev.of_node;
558 struct resource *res_regs;
559 struct tz1090_gpio priv;
560
561 if (!np) {
562 dev_err(&pdev->dev, "must be instantiated via devicetree\n");
563 return -ENOENT;
564 }
565
566 res_regs = platform_get_resource(pdev, IORESOURCE_MEM, 0);
567 if (!res_regs) {
568 dev_err(&pdev->dev, "cannot find registers resource\n");
569 return -ENOENT;
570 }
571
572 priv.dev = &pdev->dev;
573
574 /* Ioremap the registers */
575 priv.reg = devm_ioremap(&pdev->dev, res_regs->start,
576 resource_size(res_regs));
577 if (!priv.reg) {
578 dev_err(&pdev->dev, "unable to ioremap registers\n");
579 return -ENOMEM;
580 }
581
582 /* Look for banks */
583 tz1090_gpio_register_banks(&priv);
584
585 return 0;
586 }
587
588 static struct of_device_id tz1090_gpio_of_match[] = {
589 { .compatible = "img,tz1090-gpio" },
590 { },
591 };
592
593 static struct platform_driver tz1090_gpio_driver = {
594 .driver = {
595 .name = "tz1090-gpio",
596 .of_match_table = tz1090_gpio_of_match,
597 },
598 .probe = tz1090_gpio_probe,
599 };
600
601 static int __init tz1090_gpio_init(void)
602 {
603 return platform_driver_register(&tz1090_gpio_driver);
604 }
605 subsys_initcall(tz1090_gpio_init);
Linux with added FPC-III support