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14#include <linux/bitops.h>
15#include <linux/gpio/driver.h>
16#include <linux/of_device.h>
17#include <linux/of_irq.h>
18#include <linux/module.h>
19#include <linux/irqdomain.h>
20#include <linux/irqchip/chained_irq.h>
21#include <linux/interrupt.h>
22#include <linux/reboot.h>
23
24#define GIO_BANK_SIZE 0x20
25#define GIO_ODEN(bank) (((bank) * GIO_BANK_SIZE) + 0x00)
26#define GIO_DATA(bank) (((bank) * GIO_BANK_SIZE) + 0x04)
27#define GIO_IODIR(bank) (((bank) * GIO_BANK_SIZE) + 0x08)
28#define GIO_EC(bank) (((bank) * GIO_BANK_SIZE) + 0x0c)
29#define GIO_EI(bank) (((bank) * GIO_BANK_SIZE) + 0x10)
30#define GIO_MASK(bank) (((bank) * GIO_BANK_SIZE) + 0x14)
31#define GIO_LEVEL(bank) (((bank) * GIO_BANK_SIZE) + 0x18)
32#define GIO_STAT(bank) (((bank) * GIO_BANK_SIZE) + 0x1c)
33
34struct brcmstb_gpio_bank {
35 struct list_head node;
36 int id;
37 struct gpio_chip gc;
38 struct brcmstb_gpio_priv *parent_priv;
39 u32 width;
40 struct irq_chip irq_chip;
41};
42
43struct brcmstb_gpio_priv {
44 struct list_head bank_list;
45 void __iomem *reg_base;
46 struct platform_device *pdev;
47 int parent_irq;
48 int gpio_base;
49 bool can_wake;
50 int parent_wake_irq;
51 struct notifier_block reboot_notifier;
52};
53
54#define MAX_GPIO_PER_BANK 32
55#define GPIO_BANK(gpio) ((gpio) >> 5)
56
57#define GPIO_BIT(gpio) ((gpio) & (MAX_GPIO_PER_BANK - 1))
58
59static inline struct brcmstb_gpio_priv *
60brcmstb_gpio_gc_to_priv(struct gpio_chip *gc)
61{
62 struct brcmstb_gpio_bank *bank = gpiochip_get_data(gc);
63 return bank->parent_priv;
64}
65
66static void brcmstb_gpio_set_imask(struct brcmstb_gpio_bank *bank,
67 unsigned int offset, bool enable)
68{
69 struct gpio_chip *gc = &bank->gc;
70 struct brcmstb_gpio_priv *priv = bank->parent_priv;
71 u32 mask = gc->pin2mask(gc, offset);
72 u32 imask;
73 unsigned long flags;
74
75 spin_lock_irqsave(&gc->bgpio_lock, flags);
76 imask = gc->read_reg(priv->reg_base + GIO_MASK(bank->id));
77 if (enable)
78 imask |= mask;
79 else
80 imask &= ~mask;
81 gc->write_reg(priv->reg_base + GIO_MASK(bank->id), imask);
82 spin_unlock_irqrestore(&gc->bgpio_lock, flags);
83}
84
85
86
87static void brcmstb_gpio_irq_mask(struct irq_data *d)
88{
89 struct gpio_chip *gc = irq_data_get_irq_chip_data(d);
90 struct brcmstb_gpio_bank *bank = gpiochip_get_data(gc);
91
92 brcmstb_gpio_set_imask(bank, d->hwirq, false);
93}
94
95static void brcmstb_gpio_irq_unmask(struct irq_data *d)
96{
97 struct gpio_chip *gc = irq_data_get_irq_chip_data(d);
98 struct brcmstb_gpio_bank *bank = gpiochip_get_data(gc);
99
100 brcmstb_gpio_set_imask(bank, d->hwirq, true);
101}
102
103static int brcmstb_gpio_irq_set_type(struct irq_data *d, unsigned int type)
104{
105 struct gpio_chip *gc = irq_data_get_irq_chip_data(d);
106 struct brcmstb_gpio_bank *bank = gpiochip_get_data(gc);
107 struct brcmstb_gpio_priv *priv = bank->parent_priv;
108 u32 mask = BIT(d->hwirq);
109 u32 edge_insensitive, iedge_insensitive;
110 u32 edge_config, iedge_config;
111 u32 level, ilevel;
112 unsigned long flags;
113
114 switch (type) {
115 case IRQ_TYPE_LEVEL_LOW:
116 level = 0;
117 edge_config = 0;
118 edge_insensitive = 0;
119 break;
120 case IRQ_TYPE_LEVEL_HIGH:
121 level = mask;
122 edge_config = 0;
123 edge_insensitive = 0;
124 break;
125 case IRQ_TYPE_EDGE_FALLING:
126 level = 0;
127 edge_config = 0;
128 edge_insensitive = 0;
129 break;
130 case IRQ_TYPE_EDGE_RISING:
131 level = 0;
132 edge_config = mask;
133 edge_insensitive = 0;
134 break;
135 case IRQ_TYPE_EDGE_BOTH:
136 level = 0;
137 edge_config = 0;
138 edge_insensitive = mask;
139 break;
140 default:
141 return -EINVAL;
142 }
143
144 spin_lock_irqsave(&bank->gc.bgpio_lock, flags);
145
146 iedge_config = bank->gc.read_reg(priv->reg_base +
147 GIO_EC(bank->id)) & ~mask;
148 iedge_insensitive = bank->gc.read_reg(priv->reg_base +
149 GIO_EI(bank->id)) & ~mask;
150 ilevel = bank->gc.read_reg(priv->reg_base +
151 GIO_LEVEL(bank->id)) & ~mask;
152
153 bank->gc.write_reg(priv->reg_base + GIO_EC(bank->id),
154 iedge_config | edge_config);
155 bank->gc.write_reg(priv->reg_base + GIO_EI(bank->id),
156 iedge_insensitive | edge_insensitive);
157 bank->gc.write_reg(priv->reg_base + GIO_LEVEL(bank->id),
158 ilevel | level);
159
160 spin_unlock_irqrestore(&bank->gc.bgpio_lock, flags);
161 return 0;
162}
163
164static int brcmstb_gpio_priv_set_wake(struct brcmstb_gpio_priv *priv,
165 unsigned int enable)
166{
167 int ret = 0;
168
169
170
171
172
173
174 if (enable)
175 ret = enable_irq_wake(priv->parent_wake_irq);
176 else
177 ret = disable_irq_wake(priv->parent_wake_irq);
178 if (ret)
179 dev_err(&priv->pdev->dev, "failed to %s wake-up interrupt\n",
180 enable ? "enable" : "disable");
181 return ret;
182}
183
184static int brcmstb_gpio_irq_set_wake(struct irq_data *d, unsigned int enable)
185{
186 struct gpio_chip *gc = irq_data_get_irq_chip_data(d);
187 struct brcmstb_gpio_priv *priv = brcmstb_gpio_gc_to_priv(gc);
188
189 return brcmstb_gpio_priv_set_wake(priv, enable);
190}
191
192static irqreturn_t brcmstb_gpio_wake_irq_handler(int irq, void *data)
193{
194 struct brcmstb_gpio_priv *priv = data;
195
196 if (!priv || irq != priv->parent_wake_irq)
197 return IRQ_NONE;
198 pm_wakeup_event(&priv->pdev->dev, 0);
199 return IRQ_HANDLED;
200}
201
202static void brcmstb_gpio_irq_bank_handler(struct brcmstb_gpio_bank *bank)
203{
204 struct brcmstb_gpio_priv *priv = bank->parent_priv;
205 struct irq_domain *irq_domain = bank->gc.irqdomain;
206 void __iomem *reg_base = priv->reg_base;
207 unsigned long status;
208 unsigned long flags;
209
210 spin_lock_irqsave(&bank->gc.bgpio_lock, flags);
211 while ((status = bank->gc.read_reg(reg_base + GIO_STAT(bank->id)) &
212 bank->gc.read_reg(reg_base + GIO_MASK(bank->id)))) {
213 int bit;
214
215 for_each_set_bit(bit, &status, 32) {
216 u32 stat = bank->gc.read_reg(reg_base +
217 GIO_STAT(bank->id));
218 if (bit >= bank->width)
219 dev_warn(&priv->pdev->dev,
220 "IRQ for invalid GPIO (bank=%d, offset=%d)\n",
221 bank->id, bit);
222 bank->gc.write_reg(reg_base + GIO_STAT(bank->id),
223 stat | BIT(bit));
224 generic_handle_irq(irq_find_mapping(irq_domain, bit));
225 }
226 }
227 spin_unlock_irqrestore(&bank->gc.bgpio_lock, flags);
228}
229
230
231static void brcmstb_gpio_irq_handler(struct irq_desc *desc)
232{
233 struct gpio_chip *gc = irq_desc_get_handler_data(desc);
234 struct brcmstb_gpio_priv *priv = brcmstb_gpio_gc_to_priv(gc);
235 struct irq_chip *chip = irq_desc_get_chip(desc);
236 struct brcmstb_gpio_bank *bank;
237
238
239 BUG_ON(!priv || !chip);
240
241 chained_irq_enter(chip, desc);
242 list_for_each_entry(bank, &priv->bank_list, node)
243 brcmstb_gpio_irq_bank_handler(bank);
244 chained_irq_exit(chip, desc);
245}
246
247static int brcmstb_gpio_reboot(struct notifier_block *nb,
248 unsigned long action, void *data)
249{
250 struct brcmstb_gpio_priv *priv =
251 container_of(nb, struct brcmstb_gpio_priv, reboot_notifier);
252
253
254 if (action == SYS_POWER_OFF)
255 brcmstb_gpio_priv_set_wake(priv, 1);
256
257 return NOTIFY_DONE;
258}
259
260
261static int brcmstb_gpio_sanity_check_banks(struct device *dev,
262 struct device_node *np, struct resource *res)
263{
264 int res_num_banks = resource_size(res) / GIO_BANK_SIZE;
265 int num_banks =
266 of_property_count_u32_elems(np, "brcm,gpio-bank-widths");
267
268 if (res_num_banks != num_banks) {
269 dev_err(dev, "Mismatch in banks: res had %d, bank-widths had %d\n",
270 res_num_banks, num_banks);
271 return -EINVAL;
272 } else {
273 return 0;
274 }
275}
276
277static int brcmstb_gpio_remove(struct platform_device *pdev)
278{
279 struct brcmstb_gpio_priv *priv = platform_get_drvdata(pdev);
280 struct brcmstb_gpio_bank *bank;
281 int ret = 0;
282
283 if (!priv) {
284 dev_err(&pdev->dev, "called %s without drvdata!\n", __func__);
285 return -EFAULT;
286 }
287
288
289
290
291
292 list_for_each_entry(bank, &priv->bank_list, node)
293 gpiochip_remove(&bank->gc);
294
295 if (priv->reboot_notifier.notifier_call) {
296 ret = unregister_reboot_notifier(&priv->reboot_notifier);
297 if (ret)
298 dev_err(&pdev->dev,
299 "failed to unregister reboot notifier\n");
300 }
301 return ret;
302}
303
304static int brcmstb_gpio_of_xlate(struct gpio_chip *gc,
305 const struct of_phandle_args *gpiospec, u32 *flags)
306{
307 struct brcmstb_gpio_priv *priv = brcmstb_gpio_gc_to_priv(gc);
308 struct brcmstb_gpio_bank *bank = gpiochip_get_data(gc);
309 int offset;
310
311 if (gc->of_gpio_n_cells != 2) {
312 WARN_ON(1);
313 return -EINVAL;
314 }
315
316 if (WARN_ON(gpiospec->args_count < gc->of_gpio_n_cells))
317 return -EINVAL;
318
319 offset = gpiospec->args[0] - (gc->base - priv->gpio_base);
320 if (offset >= gc->ngpio || offset < 0)
321 return -EINVAL;
322
323 if (unlikely(offset >= bank->width)) {
324 dev_warn_ratelimited(&priv->pdev->dev,
325 "Received request for invalid GPIO offset %d\n",
326 gpiospec->args[0]);
327 }
328
329 if (flags)
330 *flags = gpiospec->args[1];
331
332 return offset;
333}
334
335
336static int brcmstb_gpio_irq_setup(struct platform_device *pdev,
337 struct brcmstb_gpio_bank *bank)
338{
339 struct brcmstb_gpio_priv *priv = bank->parent_priv;
340 struct device *dev = &pdev->dev;
341 struct device_node *np = dev->of_node;
342 int err;
343
344 bank->irq_chip.name = dev_name(dev);
345 bank->irq_chip.irq_mask = brcmstb_gpio_irq_mask;
346 bank->irq_chip.irq_unmask = brcmstb_gpio_irq_unmask;
347 bank->irq_chip.irq_set_type = brcmstb_gpio_irq_set_type;
348
349
350 bank->irq_chip.flags = IRQCHIP_MASK_ON_SUSPEND;
351
352 if (IS_ENABLED(CONFIG_PM_SLEEP) && !priv->can_wake &&
353 of_property_read_bool(np, "wakeup-source")) {
354 priv->parent_wake_irq = platform_get_irq(pdev, 1);
355 if (priv->parent_wake_irq < 0) {
356 dev_warn(dev,
357 "Couldn't get wake IRQ - GPIOs will not be able to wake from sleep");
358 } else {
359
360
361
362
363
364 device_set_wakeup_capable(dev, true);
365 device_wakeup_enable(dev);
366 err = devm_request_irq(dev, priv->parent_wake_irq,
367 brcmstb_gpio_wake_irq_handler, 0,
368 "brcmstb-gpio-wake", priv);
369
370 if (err < 0) {
371 dev_err(dev, "Couldn't request wake IRQ");
372 return err;
373 }
374
375 priv->reboot_notifier.notifier_call =
376 brcmstb_gpio_reboot;
377 register_reboot_notifier(&priv->reboot_notifier);
378 priv->can_wake = true;
379 }
380 }
381
382 if (priv->can_wake)
383 bank->irq_chip.irq_set_wake = brcmstb_gpio_irq_set_wake;
384
385 err = gpiochip_irqchip_add(&bank->gc, &bank->irq_chip, 0,
386 handle_simple_irq, IRQ_TYPE_NONE);
387 if (err)
388 return err;
389 gpiochip_set_chained_irqchip(&bank->gc, &bank->irq_chip,
390 priv->parent_irq, brcmstb_gpio_irq_handler);
391
392 return 0;
393}
394
395static int brcmstb_gpio_probe(struct platform_device *pdev)
396{
397 struct device *dev = &pdev->dev;
398 struct device_node *np = dev->of_node;
399 void __iomem *reg_base;
400 struct brcmstb_gpio_priv *priv;
401 struct resource *res;
402 struct property *prop;
403 const __be32 *p;
404 u32 bank_width;
405 int num_banks = 0;
406 int err;
407 static int gpio_base;
408 unsigned long flags = 0;
409
410 priv = devm_kzalloc(dev, sizeof(*priv), GFP_KERNEL);
411 if (!priv)
412 return -ENOMEM;
413 platform_set_drvdata(pdev, priv);
414 INIT_LIST_HEAD(&priv->bank_list);
415
416 res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
417 reg_base = devm_ioremap_resource(dev, res);
418 if (IS_ERR(reg_base))
419 return PTR_ERR(reg_base);
420
421 priv->gpio_base = gpio_base;
422 priv->reg_base = reg_base;
423 priv->pdev = pdev;
424
425 if (of_property_read_bool(np, "interrupt-controller")) {
426 priv->parent_irq = platform_get_irq(pdev, 0);
427 if (priv->parent_irq <= 0) {
428 dev_err(dev, "Couldn't get IRQ");
429 return -ENOENT;
430 }
431 } else {
432 priv->parent_irq = -ENOENT;
433 }
434
435 if (brcmstb_gpio_sanity_check_banks(dev, np, res))
436 return -EINVAL;
437
438
439
440
441
442
443
444
445
446#if defined(CONFIG_MIPS) && defined(__BIG_ENDIAN)
447 flags = BGPIOF_BIG_ENDIAN_BYTE_ORDER;
448#endif
449
450 of_property_for_each_u32(np, "brcm,gpio-bank-widths", prop, p,
451 bank_width) {
452 struct brcmstb_gpio_bank *bank;
453 struct gpio_chip *gc;
454
455 bank = devm_kzalloc(dev, sizeof(*bank), GFP_KERNEL);
456 if (!bank) {
457 err = -ENOMEM;
458 goto fail;
459 }
460
461 bank->parent_priv = priv;
462 bank->id = num_banks;
463 if (bank_width <= 0 || bank_width > MAX_GPIO_PER_BANK) {
464 dev_err(dev, "Invalid bank width %d\n", bank_width);
465 err = -EINVAL;
466 goto fail;
467 } else {
468 bank->width = bank_width;
469 }
470
471
472
473
474
475 gc = &bank->gc;
476 err = bgpio_init(gc, dev, 4,
477 reg_base + GIO_DATA(bank->id),
478 NULL, NULL, NULL,
479 reg_base + GIO_IODIR(bank->id), flags);
480 if (err) {
481 dev_err(dev, "bgpio_init() failed\n");
482 goto fail;
483 }
484
485 gc->of_node = np;
486 gc->owner = THIS_MODULE;
487 gc->label = devm_kasprintf(dev, GFP_KERNEL, "%pOF", dev->of_node);
488 gc->base = gpio_base;
489 gc->of_gpio_n_cells = 2;
490 gc->of_xlate = brcmstb_gpio_of_xlate;
491
492 gc->ngpio = MAX_GPIO_PER_BANK;
493
494
495
496
497
498 gc->write_reg(reg_base + GIO_MASK(bank->id), 0);
499
500 err = gpiochip_add_data(gc, bank);
501 if (err) {
502 dev_err(dev, "Could not add gpiochip for bank %d\n",
503 bank->id);
504 goto fail;
505 }
506 gpio_base += gc->ngpio;
507
508 if (priv->parent_irq > 0) {
509 err = brcmstb_gpio_irq_setup(pdev, bank);
510 if (err)
511 goto fail;
512 }
513
514 dev_dbg(dev, "bank=%d, base=%d, ngpio=%d, width=%d\n", bank->id,
515 gc->base, gc->ngpio, bank->width);
516
517
518 list_add(&bank->node, &priv->bank_list);
519
520 num_banks++;
521 }
522
523 dev_info(dev, "Registered %d banks (GPIO(s): %d-%d)\n",
524 num_banks, priv->gpio_base, gpio_base - 1);
525
526 return 0;
527
528fail:
529 (void) brcmstb_gpio_remove(pdev);
530 return err;
531}
532
533static const struct of_device_id brcmstb_gpio_of_match[] = {
534 { .compatible = "brcm,brcmstb-gpio" },
535 {},
536};
537
538MODULE_DEVICE_TABLE(of, brcmstb_gpio_of_match);
539
540static struct platform_driver brcmstb_gpio_driver = {
541 .driver = {
542 .name = "brcmstb-gpio",
543 .of_match_table = brcmstb_gpio_of_match,
544 },
545 .probe = brcmstb_gpio_probe,
546 .remove = brcmstb_gpio_remove,
547};
548module_platform_driver(brcmstb_gpio_driver);
549
550MODULE_AUTHOR("Gregory Fong");
551MODULE_DESCRIPTION("Driver for Broadcom BRCMSTB SoC UPG GPIO");
552MODULE_LICENSE("GPL v2");
553