1 // SPDX-License-Identifier: GPL-2.0
2 //
3 // Copyright (C) 2017 Socionext Inc.
4 // Author: Masahiro Yamada <yamada.masahiro@socionext.com>
5
6 #include <linux/bits.h>
7 #include <linux/gpio/driver.h>
8 #include <linux/irq.h>
9 #include <linux/irqdomain.h>
10 #include <linux/module.h>
11 #include <linux/of.h>
12 #include <linux/of_irq.h>
13 #include <linux/platform_device.h>
14 #include <linux/property.h>
15 #include <linux/spinlock.h>
16 #include <dt-bindings/gpio/uniphier-gpio.h>
17
18 #define UNIPHIER_GPIO_IRQ_MAX_NUM 24
19
20 #define UNIPHIER_GPIO_PORT_DATA 0x0 /* data */
21 #define UNIPHIER_GPIO_PORT_DIR 0x4 /* direction (1:in, 0:out) */
22 #define UNIPHIER_GPIO_IRQ_EN 0x90 /* irq enable */
23 #define UNIPHIER_GPIO_IRQ_MODE 0x94 /* irq mode (1: both edge) */
24 #define UNIPHIER_GPIO_IRQ_FLT_EN 0x98 /* noise filter enable */
25 #define UNIPHIER_GPIO_IRQ_FLT_CYC 0x9c /* noise filter clock cycle */
26
27 struct uniphier_gpio_priv {
28 struct gpio_chip chip;
29 struct irq_chip irq_chip;
30 struct irq_domain *domain;
31 void __iomem *regs;
32 spinlock_t lock;
33 u32 saved_vals[];
34 };
35
uniphier_gpio_bank_to_reg(unsigned int bank)36 static unsigned int uniphier_gpio_bank_to_reg(unsigned int bank)
37 {
38 unsigned int reg;
39
40 reg = (bank + 1) * 8;
41
42 /*
43 * Unfortunately, the GPIO port registers are not contiguous because
44 * offset 0x90-0x9f is used for IRQ. Add 0x10 when crossing the region.
45 */
46 if (reg >= UNIPHIER_GPIO_IRQ_EN)
47 reg += 0x10;
48
49 return reg;
50 }
51
uniphier_gpio_get_bank_and_mask(unsigned int offset,unsigned int * bank,u32 * mask)52 static void uniphier_gpio_get_bank_and_mask(unsigned int offset,
53 unsigned int *bank, u32 *mask)
54 {
55 *bank = offset / UNIPHIER_GPIO_LINES_PER_BANK;
56 *mask = BIT(offset % UNIPHIER_GPIO_LINES_PER_BANK);
57 }
58
uniphier_gpio_reg_update(struct uniphier_gpio_priv * priv,unsigned int reg,u32 mask,u32 val)59 static void uniphier_gpio_reg_update(struct uniphier_gpio_priv *priv,
60 unsigned int reg, u32 mask, u32 val)
61 {
62 unsigned long flags;
63 u32 tmp;
64
65 spin_lock_irqsave(&priv->lock, flags);
66 tmp = readl(priv->regs + reg);
67 tmp &= ~mask;
68 tmp |= mask & val;
69 writel(tmp, priv->regs + reg);
70 spin_unlock_irqrestore(&priv->lock, flags);
71 }
72
uniphier_gpio_bank_write(struct gpio_chip * chip,unsigned int bank,unsigned int reg,u32 mask,u32 val)73 static void uniphier_gpio_bank_write(struct gpio_chip *chip, unsigned int bank,
74 unsigned int reg, u32 mask, u32 val)
75 {
76 struct uniphier_gpio_priv *priv = gpiochip_get_data(chip);
77
78 if (!mask)
79 return;
80
81 uniphier_gpio_reg_update(priv, uniphier_gpio_bank_to_reg(bank) + reg,
82 mask, val);
83 }
84
uniphier_gpio_offset_write(struct gpio_chip * chip,unsigned int offset,unsigned int reg,int val)85 static void uniphier_gpio_offset_write(struct gpio_chip *chip,
86 unsigned int offset, unsigned int reg,
87 int val)
88 {
89 unsigned int bank;
90 u32 mask;
91
92 uniphier_gpio_get_bank_and_mask(offset, &bank, &mask);
93
94 uniphier_gpio_bank_write(chip, bank, reg, mask, val ? mask : 0);
95 }
96
uniphier_gpio_offset_read(struct gpio_chip * chip,unsigned int offset,unsigned int reg)97 static int uniphier_gpio_offset_read(struct gpio_chip *chip,
98 unsigned int offset, unsigned int reg)
99 {
100 struct uniphier_gpio_priv *priv = gpiochip_get_data(chip);
101 unsigned int bank, reg_offset;
102 u32 mask;
103
104 uniphier_gpio_get_bank_and_mask(offset, &bank, &mask);
105 reg_offset = uniphier_gpio_bank_to_reg(bank) + reg;
106
107 return !!(readl(priv->regs + reg_offset) & mask);
108 }
109
uniphier_gpio_get_direction(struct gpio_chip * chip,unsigned int offset)110 static int uniphier_gpio_get_direction(struct gpio_chip *chip,
111 unsigned int offset)
112 {
113 if (uniphier_gpio_offset_read(chip, offset, UNIPHIER_GPIO_PORT_DIR))
114 return GPIO_LINE_DIRECTION_IN;
115
116 return GPIO_LINE_DIRECTION_OUT;
117 }
118
uniphier_gpio_direction_input(struct gpio_chip * chip,unsigned int offset)119 static int uniphier_gpio_direction_input(struct gpio_chip *chip,
120 unsigned int offset)
121 {
122 uniphier_gpio_offset_write(chip, offset, UNIPHIER_GPIO_PORT_DIR, 1);
123
124 return 0;
125 }
126
uniphier_gpio_direction_output(struct gpio_chip * chip,unsigned int offset,int val)127 static int uniphier_gpio_direction_output(struct gpio_chip *chip,
128 unsigned int offset, int val)
129 {
130 uniphier_gpio_offset_write(chip, offset, UNIPHIER_GPIO_PORT_DATA, val);
131 uniphier_gpio_offset_write(chip, offset, UNIPHIER_GPIO_PORT_DIR, 0);
132
133 return 0;
134 }
135
uniphier_gpio_get(struct gpio_chip * chip,unsigned int offset)136 static int uniphier_gpio_get(struct gpio_chip *chip, unsigned int offset)
137 {
138 return uniphier_gpio_offset_read(chip, offset, UNIPHIER_GPIO_PORT_DATA);
139 }
140
uniphier_gpio_set(struct gpio_chip * chip,unsigned int offset,int val)141 static void uniphier_gpio_set(struct gpio_chip *chip,
142 unsigned int offset, int val)
143 {
144 uniphier_gpio_offset_write(chip, offset, UNIPHIER_GPIO_PORT_DATA, val);
145 }
146
uniphier_gpio_set_multiple(struct gpio_chip * chip,unsigned long * mask,unsigned long * bits)147 static void uniphier_gpio_set_multiple(struct gpio_chip *chip,
148 unsigned long *mask, unsigned long *bits)
149 {
150 unsigned long i, bank, bank_mask, bank_bits;
151
152 for_each_set_clump8(i, bank_mask, mask, chip->ngpio) {
153 bank = i / UNIPHIER_GPIO_LINES_PER_BANK;
154 bank_bits = bitmap_get_value8(bits, i);
155
156 uniphier_gpio_bank_write(chip, bank, UNIPHIER_GPIO_PORT_DATA,
157 bank_mask, bank_bits);
158 }
159 }
160
uniphier_gpio_to_irq(struct gpio_chip * chip,unsigned int offset)161 static int uniphier_gpio_to_irq(struct gpio_chip *chip, unsigned int offset)
162 {
163 struct irq_fwspec fwspec;
164
165 if (offset < UNIPHIER_GPIO_IRQ_OFFSET)
166 return -ENXIO;
167
168 fwspec.fwnode = dev_fwnode(chip->parent);
169 fwspec.param_count = 2;
170 fwspec.param[0] = offset - UNIPHIER_GPIO_IRQ_OFFSET;
171 /*
172 * IRQ_TYPE_NONE is rejected by the parent irq domain. Set LEVEL_HIGH
173 * temporarily. Anyway, ->irq_set_type() will override it later.
174 */
175 fwspec.param[1] = IRQ_TYPE_LEVEL_HIGH;
176
177 return irq_create_fwspec_mapping(&fwspec);
178 }
179
uniphier_gpio_irq_mask(struct irq_data * data)180 static void uniphier_gpio_irq_mask(struct irq_data *data)
181 {
182 struct uniphier_gpio_priv *priv = irq_data_get_irq_chip_data(data);
183 u32 mask = BIT(irqd_to_hwirq(data));
184
185 uniphier_gpio_reg_update(priv, UNIPHIER_GPIO_IRQ_EN, mask, 0);
186
187 irq_chip_mask_parent(data);
188 }
189
uniphier_gpio_irq_unmask(struct irq_data * data)190 static void uniphier_gpio_irq_unmask(struct irq_data *data)
191 {
192 struct uniphier_gpio_priv *priv = irq_data_get_irq_chip_data(data);
193 u32 mask = BIT(irqd_to_hwirq(data));
194
195 uniphier_gpio_reg_update(priv, UNIPHIER_GPIO_IRQ_EN, mask, mask);
196
197 irq_chip_unmask_parent(data);
198 }
199
uniphier_gpio_irq_set_type(struct irq_data * data,unsigned int type)200 static int uniphier_gpio_irq_set_type(struct irq_data *data, unsigned int type)
201 {
202 struct uniphier_gpio_priv *priv = irq_data_get_irq_chip_data(data);
203 u32 mask = BIT(irqd_to_hwirq(data));
204 u32 val = 0;
205
206 if (type == IRQ_TYPE_EDGE_BOTH) {
207 val = mask;
208 type = IRQ_TYPE_EDGE_FALLING;
209 }
210
211 uniphier_gpio_reg_update(priv, UNIPHIER_GPIO_IRQ_MODE, mask, val);
212 /* To enable both edge detection, the noise filter must be enabled. */
213 uniphier_gpio_reg_update(priv, UNIPHIER_GPIO_IRQ_FLT_EN, mask, val);
214
215 return irq_chip_set_type_parent(data, type);
216 }
217
uniphier_gpio_irq_get_parent_hwirq(struct uniphier_gpio_priv * priv,unsigned int hwirq)218 static int uniphier_gpio_irq_get_parent_hwirq(struct uniphier_gpio_priv *priv,
219 unsigned int hwirq)
220 {
221 struct device_node *np = priv->chip.parent->of_node;
222 const __be32 *range;
223 u32 base, parent_base, size;
224 int len;
225
226 range = of_get_property(np, "socionext,interrupt-ranges", &len);
227 if (!range)
228 return -EINVAL;
229
230 len /= sizeof(*range);
231
232 for (; len >= 3; len -= 3) {
233 base = be32_to_cpu(*range++);
234 parent_base = be32_to_cpu(*range++);
235 size = be32_to_cpu(*range++);
236
237 if (base <= hwirq && hwirq < base + size)
238 return hwirq - base + parent_base;
239 }
240
241 return -ENOENT;
242 }
243
uniphier_gpio_irq_domain_translate(struct irq_domain * domain,struct irq_fwspec * fwspec,unsigned long * out_hwirq,unsigned int * out_type)244 static int uniphier_gpio_irq_domain_translate(struct irq_domain *domain,
245 struct irq_fwspec *fwspec,
246 unsigned long *out_hwirq,
247 unsigned int *out_type)
248 {
249 if (WARN_ON(fwspec->param_count < 2))
250 return -EINVAL;
251
252 *out_hwirq = fwspec->param[0];
253 *out_type = fwspec->param[1] & IRQ_TYPE_SENSE_MASK;
254
255 return 0;
256 }
257
uniphier_gpio_irq_domain_alloc(struct irq_domain * domain,unsigned int virq,unsigned int nr_irqs,void * arg)258 static int uniphier_gpio_irq_domain_alloc(struct irq_domain *domain,
259 unsigned int virq,
260 unsigned int nr_irqs, void *arg)
261 {
262 struct uniphier_gpio_priv *priv = domain->host_data;
263 struct irq_fwspec parent_fwspec;
264 irq_hw_number_t hwirq;
265 unsigned int type;
266 int ret;
267
268 if (WARN_ON(nr_irqs != 1))
269 return -EINVAL;
270
271 ret = uniphier_gpio_irq_domain_translate(domain, arg, &hwirq, &type);
272 if (ret)
273 return ret;
274
275 ret = uniphier_gpio_irq_get_parent_hwirq(priv, hwirq);
276 if (ret < 0)
277 return ret;
278
279 /* parent is UniPhier AIDET */
280 parent_fwspec.fwnode = domain->parent->fwnode;
281 parent_fwspec.param_count = 2;
282 parent_fwspec.param[0] = ret;
283 parent_fwspec.param[1] = (type == IRQ_TYPE_EDGE_BOTH) ?
284 IRQ_TYPE_EDGE_FALLING : type;
285
286 ret = irq_domain_set_hwirq_and_chip(domain, virq, hwirq,
287 &priv->irq_chip, priv);
288 if (ret)
289 return ret;
290
291 return irq_domain_alloc_irqs_parent(domain, virq, 1, &parent_fwspec);
292 }
293
uniphier_gpio_irq_domain_activate(struct irq_domain * domain,struct irq_data * data,bool early)294 static int uniphier_gpio_irq_domain_activate(struct irq_domain *domain,
295 struct irq_data *data, bool early)
296 {
297 struct uniphier_gpio_priv *priv = domain->host_data;
298 struct gpio_chip *chip = &priv->chip;
299
300 return gpiochip_lock_as_irq(chip,
301 irqd_to_hwirq(data) + UNIPHIER_GPIO_IRQ_OFFSET);
302 }
303
uniphier_gpio_irq_domain_deactivate(struct irq_domain * domain,struct irq_data * data)304 static void uniphier_gpio_irq_domain_deactivate(struct irq_domain *domain,
305 struct irq_data *data)
306 {
307 struct uniphier_gpio_priv *priv = domain->host_data;
308 struct gpio_chip *chip = &priv->chip;
309
310 gpiochip_unlock_as_irq(chip,
311 irqd_to_hwirq(data) + UNIPHIER_GPIO_IRQ_OFFSET);
312 }
313
314 static const struct irq_domain_ops uniphier_gpio_irq_domain_ops = {
315 .alloc = uniphier_gpio_irq_domain_alloc,
316 .free = irq_domain_free_irqs_common,
317 .activate = uniphier_gpio_irq_domain_activate,
318 .deactivate = uniphier_gpio_irq_domain_deactivate,
319 .translate = uniphier_gpio_irq_domain_translate,
320 };
321
uniphier_gpio_hw_init(struct uniphier_gpio_priv * priv)322 static void uniphier_gpio_hw_init(struct uniphier_gpio_priv *priv)
323 {
324 /*
325 * Due to the hardware design, the noise filter must be enabled to
326 * detect both edge interrupts. This filter is intended to remove the
327 * noise from the irq lines. It does not work for GPIO input, so GPIO
328 * debounce is not supported. Unfortunately, the filter period is
329 * shared among all irq lines. Just choose a sensible period here.
330 */
331 writel(0xff, priv->regs + UNIPHIER_GPIO_IRQ_FLT_CYC);
332 }
333
uniphier_gpio_get_nbanks(unsigned int ngpio)334 static unsigned int uniphier_gpio_get_nbanks(unsigned int ngpio)
335 {
336 return DIV_ROUND_UP(ngpio, UNIPHIER_GPIO_LINES_PER_BANK);
337 }
338
uniphier_gpio_probe(struct platform_device * pdev)339 static int uniphier_gpio_probe(struct platform_device *pdev)
340 {
341 struct device *dev = &pdev->dev;
342 struct device_node *parent_np;
343 struct irq_domain *parent_domain;
344 struct uniphier_gpio_priv *priv;
345 struct gpio_chip *chip;
346 struct irq_chip *irq_chip;
347 unsigned int nregs;
348 u32 ngpios;
349 int ret;
350
351 parent_np = of_irq_find_parent(dev->of_node);
352 if (!parent_np)
353 return -ENXIO;
354
355 parent_domain = irq_find_host(parent_np);
356 of_node_put(parent_np);
357 if (!parent_domain)
358 return -EPROBE_DEFER;
359
360 ret = of_property_read_u32(dev->of_node, "ngpios", &ngpios);
361 if (ret)
362 return ret;
363
364 nregs = uniphier_gpio_get_nbanks(ngpios) * 2 + 3;
365 priv = devm_kzalloc(dev, struct_size(priv, saved_vals, nregs),
366 GFP_KERNEL);
367 if (!priv)
368 return -ENOMEM;
369
370 priv->regs = devm_platform_ioremap_resource(pdev, 0);
371 if (IS_ERR(priv->regs))
372 return PTR_ERR(priv->regs);
373
374 spin_lock_init(&priv->lock);
375
376 chip = &priv->chip;
377 chip->label = dev_name(dev);
378 chip->parent = dev;
379 chip->request = gpiochip_generic_request;
380 chip->free = gpiochip_generic_free;
381 chip->get_direction = uniphier_gpio_get_direction;
382 chip->direction_input = uniphier_gpio_direction_input;
383 chip->direction_output = uniphier_gpio_direction_output;
384 chip->get = uniphier_gpio_get;
385 chip->set = uniphier_gpio_set;
386 chip->set_multiple = uniphier_gpio_set_multiple;
387 chip->to_irq = uniphier_gpio_to_irq;
388 chip->base = -1;
389 chip->ngpio = ngpios;
390
391 irq_chip = &priv->irq_chip;
392 irq_chip->name = dev_name(dev);
393 irq_chip->irq_mask = uniphier_gpio_irq_mask;
394 irq_chip->irq_unmask = uniphier_gpio_irq_unmask;
395 irq_chip->irq_eoi = irq_chip_eoi_parent;
396 irq_chip->irq_set_affinity = irq_chip_set_affinity_parent;
397 irq_chip->irq_set_type = uniphier_gpio_irq_set_type;
398
399 uniphier_gpio_hw_init(priv);
400
401 ret = devm_gpiochip_add_data(dev, chip, priv);
402 if (ret)
403 return ret;
404
405 priv->domain = irq_domain_create_hierarchy(
406 parent_domain, 0,
407 UNIPHIER_GPIO_IRQ_MAX_NUM,
408 dev_fwnode(dev),
409 &uniphier_gpio_irq_domain_ops, priv);
410 if (!priv->domain)
411 return -ENOMEM;
412
413 platform_set_drvdata(pdev, priv);
414
415 return 0;
416 }
417
uniphier_gpio_remove(struct platform_device * pdev)418 static void uniphier_gpio_remove(struct platform_device *pdev)
419 {
420 struct uniphier_gpio_priv *priv = platform_get_drvdata(pdev);
421
422 irq_domain_remove(priv->domain);
423 }
424
uniphier_gpio_suspend(struct device * dev)425 static int __maybe_unused uniphier_gpio_suspend(struct device *dev)
426 {
427 struct uniphier_gpio_priv *priv = dev_get_drvdata(dev);
428 unsigned int nbanks = uniphier_gpio_get_nbanks(priv->chip.ngpio);
429 u32 *val = priv->saved_vals;
430 unsigned int reg;
431 int i;
432
433 for (i = 0; i < nbanks; i++) {
434 reg = uniphier_gpio_bank_to_reg(i);
435
436 *val++ = readl(priv->regs + reg + UNIPHIER_GPIO_PORT_DATA);
437 *val++ = readl(priv->regs + reg + UNIPHIER_GPIO_PORT_DIR);
438 }
439
440 *val++ = readl(priv->regs + UNIPHIER_GPIO_IRQ_EN);
441 *val++ = readl(priv->regs + UNIPHIER_GPIO_IRQ_MODE);
442 *val++ = readl(priv->regs + UNIPHIER_GPIO_IRQ_FLT_EN);
443
444 return 0;
445 }
446
uniphier_gpio_resume(struct device * dev)447 static int __maybe_unused uniphier_gpio_resume(struct device *dev)
448 {
449 struct uniphier_gpio_priv *priv = dev_get_drvdata(dev);
450 unsigned int nbanks = uniphier_gpio_get_nbanks(priv->chip.ngpio);
451 const u32 *val = priv->saved_vals;
452 unsigned int reg;
453 int i;
454
455 for (i = 0; i < nbanks; i++) {
456 reg = uniphier_gpio_bank_to_reg(i);
457
458 writel(*val++, priv->regs + reg + UNIPHIER_GPIO_PORT_DATA);
459 writel(*val++, priv->regs + reg + UNIPHIER_GPIO_PORT_DIR);
460 }
461
462 writel(*val++, priv->regs + UNIPHIER_GPIO_IRQ_EN);
463 writel(*val++, priv->regs + UNIPHIER_GPIO_IRQ_MODE);
464 writel(*val++, priv->regs + UNIPHIER_GPIO_IRQ_FLT_EN);
465
466 uniphier_gpio_hw_init(priv);
467
468 return 0;
469 }
470
471 static const struct dev_pm_ops uniphier_gpio_pm_ops = {
472 SET_LATE_SYSTEM_SLEEP_PM_OPS(uniphier_gpio_suspend,
473 uniphier_gpio_resume)
474 };
475
476 static const struct of_device_id uniphier_gpio_match[] = {
477 { .compatible = "socionext,uniphier-gpio" },
478 { /* sentinel */ }
479 };
480 MODULE_DEVICE_TABLE(of, uniphier_gpio_match);
481
482 static struct platform_driver uniphier_gpio_driver = {
483 .probe = uniphier_gpio_probe,
484 .remove = uniphier_gpio_remove,
485 .driver = {
486 .name = "uniphier-gpio",
487 .of_match_table = uniphier_gpio_match,
488 .pm = &uniphier_gpio_pm_ops,
489 },
490 };
491 module_platform_driver(uniphier_gpio_driver);
492
493 MODULE_AUTHOR("Masahiro Yamada <yamada.masahiro@socionext.com>");
494 MODULE_DESCRIPTION("UniPhier GPIO driver");
495 MODULE_LICENSE("GPL v2");
496