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_device.h>
13 #include <linux/of_irq.h>
14 #include <linux/platform_device.h>
15 #include <linux/spinlock.h>
16 #include <dt-bindings/gpio/uniphier-gpio.h>
17
18 #define UNIPHIER_GPIO_BANK_MASK \
19 GENMASK((UNIPHIER_GPIO_LINES_PER_BANK) - 1, 0)
20
21 #define UNIPHIER_GPIO_IRQ_MAX_NUM 24
22
23 #define UNIPHIER_GPIO_PORT_DATA 0x0 /* data */
24 #define UNIPHIER_GPIO_PORT_DIR 0x4 /* direction (1:in, 0:out) */
25 #define UNIPHIER_GPIO_IRQ_EN 0x90 /* irq enable */
26 #define UNIPHIER_GPIO_IRQ_MODE 0x94 /* irq mode (1: both edge) */
27 #define UNIPHIER_GPIO_IRQ_FLT_EN 0x98 /* noise filter enable */
28 #define UNIPHIER_GPIO_IRQ_FLT_CYC 0x9c /* noise filter clock cycle */
29
30 struct uniphier_gpio_priv {
31 struct gpio_chip chip;
32 struct irq_chip irq_chip;
33 struct irq_domain *domain;
34 void __iomem *regs;
35 spinlock_t lock;
36 u32 saved_vals[0];
37 };
38
uniphier_gpio_bank_to_reg(unsigned int bank)39 static unsigned int uniphier_gpio_bank_to_reg(unsigned int bank)
40 {
41 unsigned int reg;
42
43 reg = (bank + 1) * 8;
44
45 /*
46 * Unfortunately, the GPIO port registers are not contiguous because
47 * offset 0x90-0x9f is used for IRQ. Add 0x10 when crossing the region.
48 */
49 if (reg >= UNIPHIER_GPIO_IRQ_EN)
50 reg += 0x10;
51
52 return reg;
53 }
54
uniphier_gpio_get_bank_and_mask(unsigned int offset,unsigned int * bank,u32 * mask)55 static void uniphier_gpio_get_bank_and_mask(unsigned int offset,
56 unsigned int *bank, u32 *mask)
57 {
58 *bank = offset / UNIPHIER_GPIO_LINES_PER_BANK;
59 *mask = BIT(offset % UNIPHIER_GPIO_LINES_PER_BANK);
60 }
61
uniphier_gpio_reg_update(struct uniphier_gpio_priv * priv,unsigned int reg,u32 mask,u32 val)62 static void uniphier_gpio_reg_update(struct uniphier_gpio_priv *priv,
63 unsigned int reg, u32 mask, u32 val)
64 {
65 unsigned long flags;
66 u32 tmp;
67
68 spin_lock_irqsave(&priv->lock, flags);
69 tmp = readl(priv->regs + reg);
70 tmp &= ~mask;
71 tmp |= mask & val;
72 writel(tmp, priv->regs + reg);
73 spin_unlock_irqrestore(&priv->lock, flags);
74 }
75
uniphier_gpio_bank_write(struct gpio_chip * chip,unsigned int bank,unsigned int reg,u32 mask,u32 val)76 static void uniphier_gpio_bank_write(struct gpio_chip *chip, unsigned int bank,
77 unsigned int reg, u32 mask, u32 val)
78 {
79 struct uniphier_gpio_priv *priv = gpiochip_get_data(chip);
80
81 if (!mask)
82 return;
83
84 uniphier_gpio_reg_update(priv, uniphier_gpio_bank_to_reg(bank) + reg,
85 mask, val);
86 }
87
uniphier_gpio_offset_write(struct gpio_chip * chip,unsigned int offset,unsigned int reg,int val)88 static void uniphier_gpio_offset_write(struct gpio_chip *chip,
89 unsigned int offset, unsigned int reg,
90 int val)
91 {
92 unsigned int bank;
93 u32 mask;
94
95 uniphier_gpio_get_bank_and_mask(offset, &bank, &mask);
96
97 uniphier_gpio_bank_write(chip, bank, reg, mask, val ? mask : 0);
98 }
99
uniphier_gpio_offset_read(struct gpio_chip * chip,unsigned int offset,unsigned int reg)100 static int uniphier_gpio_offset_read(struct gpio_chip *chip,
101 unsigned int offset, unsigned int reg)
102 {
103 struct uniphier_gpio_priv *priv = gpiochip_get_data(chip);
104 unsigned int bank, reg_offset;
105 u32 mask;
106
107 uniphier_gpio_get_bank_and_mask(offset, &bank, &mask);
108 reg_offset = uniphier_gpio_bank_to_reg(bank) + reg;
109
110 return !!(readl(priv->regs + reg_offset) & mask);
111 }
112
uniphier_gpio_get_direction(struct gpio_chip * chip,unsigned int offset)113 static int uniphier_gpio_get_direction(struct gpio_chip *chip,
114 unsigned int offset)
115 {
116 return uniphier_gpio_offset_read(chip, offset, UNIPHIER_GPIO_PORT_DIR);
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 int bank, shift, bank_mask, bank_bits;
151 int i;
152
153 for (i = 0; i < chip->ngpio; i += UNIPHIER_GPIO_LINES_PER_BANK) {
154 bank = i / UNIPHIER_GPIO_LINES_PER_BANK;
155 shift = i % BITS_PER_LONG;
156 bank_mask = (mask[BIT_WORD(i)] >> shift) &
157 UNIPHIER_GPIO_BANK_MASK;
158 bank_bits = bits[BIT_WORD(i)] >> shift;
159
160 uniphier_gpio_bank_write(chip, bank, UNIPHIER_GPIO_PORT_DATA,
161 bank_mask, bank_bits);
162 }
163 }
164
uniphier_gpio_to_irq(struct gpio_chip * chip,unsigned int offset)165 static int uniphier_gpio_to_irq(struct gpio_chip *chip, unsigned int offset)
166 {
167 struct irq_fwspec fwspec;
168
169 if (offset < UNIPHIER_GPIO_IRQ_OFFSET)
170 return -ENXIO;
171
172 fwspec.fwnode = of_node_to_fwnode(chip->parent->of_node);
173 fwspec.param_count = 2;
174 fwspec.param[0] = offset - UNIPHIER_GPIO_IRQ_OFFSET;
175 /*
176 * IRQ_TYPE_NONE is rejected by the parent irq domain. Set LEVEL_HIGH
177 * temporarily. Anyway, ->irq_set_type() will override it later.
178 */
179 fwspec.param[1] = IRQ_TYPE_LEVEL_HIGH;
180
181 return irq_create_fwspec_mapping(&fwspec);
182 }
183
uniphier_gpio_irq_mask(struct irq_data * data)184 static void uniphier_gpio_irq_mask(struct irq_data *data)
185 {
186 struct uniphier_gpio_priv *priv = data->chip_data;
187 u32 mask = BIT(data->hwirq);
188
189 uniphier_gpio_reg_update(priv, UNIPHIER_GPIO_IRQ_EN, mask, 0);
190
191 return irq_chip_mask_parent(data);
192 }
193
uniphier_gpio_irq_unmask(struct irq_data * data)194 static void uniphier_gpio_irq_unmask(struct irq_data *data)
195 {
196 struct uniphier_gpio_priv *priv = data->chip_data;
197 u32 mask = BIT(data->hwirq);
198
199 uniphier_gpio_reg_update(priv, UNIPHIER_GPIO_IRQ_EN, mask, mask);
200
201 return irq_chip_unmask_parent(data);
202 }
203
uniphier_gpio_irq_set_type(struct irq_data * data,unsigned int type)204 static int uniphier_gpio_irq_set_type(struct irq_data *data, unsigned int type)
205 {
206 struct uniphier_gpio_priv *priv = data->chip_data;
207 u32 mask = BIT(data->hwirq);
208 u32 val = 0;
209
210 if (type == IRQ_TYPE_EDGE_BOTH) {
211 val = mask;
212 type = IRQ_TYPE_EDGE_FALLING;
213 }
214
215 uniphier_gpio_reg_update(priv, UNIPHIER_GPIO_IRQ_MODE, mask, val);
216 /* To enable both edge detection, the noise filter must be enabled. */
217 uniphier_gpio_reg_update(priv, UNIPHIER_GPIO_IRQ_FLT_EN, mask, val);
218
219 return irq_chip_set_type_parent(data, type);
220 }
221
uniphier_gpio_irq_get_parent_hwirq(struct uniphier_gpio_priv * priv,unsigned int hwirq)222 static int uniphier_gpio_irq_get_parent_hwirq(struct uniphier_gpio_priv *priv,
223 unsigned int hwirq)
224 {
225 struct device_node *np = priv->chip.parent->of_node;
226 const __be32 *range;
227 u32 base, parent_base, size;
228 int len;
229
230 range = of_get_property(np, "socionext,interrupt-ranges", &len);
231 if (!range)
232 return -EINVAL;
233
234 len /= sizeof(*range);
235
236 for (; len >= 3; len -= 3) {
237 base = be32_to_cpu(*range++);
238 parent_base = be32_to_cpu(*range++);
239 size = be32_to_cpu(*range++);
240
241 if (base <= hwirq && hwirq < base + size)
242 return hwirq - base + parent_base;
243 }
244
245 return -ENOENT;
246 }
247
uniphier_gpio_irq_domain_translate(struct irq_domain * domain,struct irq_fwspec * fwspec,unsigned long * out_hwirq,unsigned int * out_type)248 static int uniphier_gpio_irq_domain_translate(struct irq_domain *domain,
249 struct irq_fwspec *fwspec,
250 unsigned long *out_hwirq,
251 unsigned int *out_type)
252 {
253 if (WARN_ON(fwspec->param_count < 2))
254 return -EINVAL;
255
256 *out_hwirq = fwspec->param[0];
257 *out_type = fwspec->param[1] & IRQ_TYPE_SENSE_MASK;
258
259 return 0;
260 }
261
uniphier_gpio_irq_domain_alloc(struct irq_domain * domain,unsigned int virq,unsigned int nr_irqs,void * arg)262 static int uniphier_gpio_irq_domain_alloc(struct irq_domain *domain,
263 unsigned int virq,
264 unsigned int nr_irqs, void *arg)
265 {
266 struct uniphier_gpio_priv *priv = domain->host_data;
267 struct irq_fwspec parent_fwspec;
268 irq_hw_number_t hwirq;
269 unsigned int type;
270 int ret;
271
272 if (WARN_ON(nr_irqs != 1))
273 return -EINVAL;
274
275 ret = uniphier_gpio_irq_domain_translate(domain, arg, &hwirq, &type);
276 if (ret)
277 return ret;
278
279 ret = uniphier_gpio_irq_get_parent_hwirq(priv, hwirq);
280 if (ret < 0)
281 return ret;
282
283 /* parent is UniPhier AIDET */
284 parent_fwspec.fwnode = domain->parent->fwnode;
285 parent_fwspec.param_count = 2;
286 parent_fwspec.param[0] = ret;
287 parent_fwspec.param[1] = (type == IRQ_TYPE_EDGE_BOTH) ?
288 IRQ_TYPE_EDGE_FALLING : type;
289
290 ret = irq_domain_set_hwirq_and_chip(domain, virq, hwirq,
291 &priv->irq_chip, priv);
292 if (ret)
293 return ret;
294
295 return irq_domain_alloc_irqs_parent(domain, virq, 1, &parent_fwspec);
296 }
297
uniphier_gpio_irq_domain_activate(struct irq_domain * domain,struct irq_data * data,bool early)298 static int uniphier_gpio_irq_domain_activate(struct irq_domain *domain,
299 struct irq_data *data, bool early)
300 {
301 struct uniphier_gpio_priv *priv = domain->host_data;
302 struct gpio_chip *chip = &priv->chip;
303
304 return gpiochip_lock_as_irq(chip, data->hwirq + UNIPHIER_GPIO_IRQ_OFFSET);
305 }
306
uniphier_gpio_irq_domain_deactivate(struct irq_domain * domain,struct irq_data * data)307 static void uniphier_gpio_irq_domain_deactivate(struct irq_domain *domain,
308 struct irq_data *data)
309 {
310 struct uniphier_gpio_priv *priv = domain->host_data;
311 struct gpio_chip *chip = &priv->chip;
312
313 gpiochip_unlock_as_irq(chip, data->hwirq + UNIPHIER_GPIO_IRQ_OFFSET);
314 }
315
316 static const struct irq_domain_ops uniphier_gpio_irq_domain_ops = {
317 .alloc = uniphier_gpio_irq_domain_alloc,
318 .free = irq_domain_free_irqs_common,
319 .activate = uniphier_gpio_irq_domain_activate,
320 .deactivate = uniphier_gpio_irq_domain_deactivate,
321 .translate = uniphier_gpio_irq_domain_translate,
322 };
323
uniphier_gpio_hw_init(struct uniphier_gpio_priv * priv)324 static void uniphier_gpio_hw_init(struct uniphier_gpio_priv *priv)
325 {
326 /*
327 * Due to the hardware design, the noise filter must be enabled to
328 * detect both edge interrupts. This filter is intended to remove the
329 * noise from the irq lines. It does not work for GPIO input, so GPIO
330 * debounce is not supported. Unfortunately, the filter period is
331 * shared among all irq lines. Just choose a sensible period here.
332 */
333 writel(0xff, priv->regs + UNIPHIER_GPIO_IRQ_FLT_CYC);
334 }
335
uniphier_gpio_get_nbanks(unsigned int ngpio)336 static unsigned int uniphier_gpio_get_nbanks(unsigned int ngpio)
337 {
338 return DIV_ROUND_UP(ngpio, UNIPHIER_GPIO_LINES_PER_BANK);
339 }
340
uniphier_gpio_probe(struct platform_device * pdev)341 static int uniphier_gpio_probe(struct platform_device *pdev)
342 {
343 struct device *dev = &pdev->dev;
344 struct device_node *parent_np;
345 struct irq_domain *parent_domain;
346 struct uniphier_gpio_priv *priv;
347 struct gpio_chip *chip;
348 struct irq_chip *irq_chip;
349 unsigned int nregs;
350 u32 ngpios;
351 int ret;
352
353 parent_np = of_irq_find_parent(dev->of_node);
354 if (!parent_np)
355 return -ENXIO;
356
357 parent_domain = irq_find_host(parent_np);
358 of_node_put(parent_np);
359 if (!parent_domain)
360 return -EPROBE_DEFER;
361
362 ret = of_property_read_u32(dev->of_node, "ngpios", &ngpios);
363 if (ret)
364 return ret;
365
366 nregs = uniphier_gpio_get_nbanks(ngpios) * 2 + 3;
367 priv = devm_kzalloc(dev, struct_size(priv, saved_vals, nregs),
368 GFP_KERNEL);
369 if (!priv)
370 return -ENOMEM;
371
372 priv->regs = devm_platform_ioremap_resource(pdev, 0);
373 if (IS_ERR(priv->regs))
374 return PTR_ERR(priv->regs);
375
376 spin_lock_init(&priv->lock);
377
378 chip = &priv->chip;
379 chip->label = dev_name(dev);
380 chip->parent = dev;
381 chip->request = gpiochip_generic_request;
382 chip->free = gpiochip_generic_free;
383 chip->get_direction = uniphier_gpio_get_direction;
384 chip->direction_input = uniphier_gpio_direction_input;
385 chip->direction_output = uniphier_gpio_direction_output;
386 chip->get = uniphier_gpio_get;
387 chip->set = uniphier_gpio_set;
388 chip->set_multiple = uniphier_gpio_set_multiple;
389 chip->to_irq = uniphier_gpio_to_irq;
390 chip->base = -1;
391 chip->ngpio = ngpios;
392
393 irq_chip = &priv->irq_chip;
394 irq_chip->name = dev_name(dev);
395 irq_chip->irq_mask = uniphier_gpio_irq_mask;
396 irq_chip->irq_unmask = uniphier_gpio_irq_unmask;
397 irq_chip->irq_eoi = irq_chip_eoi_parent;
398 irq_chip->irq_set_affinity = irq_chip_set_affinity_parent;
399 irq_chip->irq_set_type = uniphier_gpio_irq_set_type;
400
401 uniphier_gpio_hw_init(priv);
402
403 ret = devm_gpiochip_add_data(dev, chip, priv);
404 if (ret)
405 return ret;
406
407 priv->domain = irq_domain_create_hierarchy(
408 parent_domain, 0,
409 UNIPHIER_GPIO_IRQ_MAX_NUM,
410 of_node_to_fwnode(dev->of_node),
411 &uniphier_gpio_irq_domain_ops, priv);
412 if (!priv->domain)
413 return -ENOMEM;
414
415 platform_set_drvdata(pdev, priv);
416
417 return 0;
418 }
419
uniphier_gpio_remove(struct platform_device * pdev)420 static int uniphier_gpio_remove(struct platform_device *pdev)
421 {
422 struct uniphier_gpio_priv *priv = platform_get_drvdata(pdev);
423
424 irq_domain_remove(priv->domain);
425
426 return 0;
427 }
428
uniphier_gpio_suspend(struct device * dev)429 static int __maybe_unused uniphier_gpio_suspend(struct device *dev)
430 {
431 struct uniphier_gpio_priv *priv = dev_get_drvdata(dev);
432 unsigned int nbanks = uniphier_gpio_get_nbanks(priv->chip.ngpio);
433 u32 *val = priv->saved_vals;
434 unsigned int reg;
435 int i;
436
437 for (i = 0; i < nbanks; i++) {
438 reg = uniphier_gpio_bank_to_reg(i);
439
440 *val++ = readl(priv->regs + reg + UNIPHIER_GPIO_PORT_DATA);
441 *val++ = readl(priv->regs + reg + UNIPHIER_GPIO_PORT_DIR);
442 }
443
444 *val++ = readl(priv->regs + UNIPHIER_GPIO_IRQ_EN);
445 *val++ = readl(priv->regs + UNIPHIER_GPIO_IRQ_MODE);
446 *val++ = readl(priv->regs + UNIPHIER_GPIO_IRQ_FLT_EN);
447
448 return 0;
449 }
450
uniphier_gpio_resume(struct device * dev)451 static int __maybe_unused uniphier_gpio_resume(struct device *dev)
452 {
453 struct uniphier_gpio_priv *priv = dev_get_drvdata(dev);
454 unsigned int nbanks = uniphier_gpio_get_nbanks(priv->chip.ngpio);
455 const u32 *val = priv->saved_vals;
456 unsigned int reg;
457 int i;
458
459 for (i = 0; i < nbanks; i++) {
460 reg = uniphier_gpio_bank_to_reg(i);
461
462 writel(*val++, priv->regs + reg + UNIPHIER_GPIO_PORT_DATA);
463 writel(*val++, priv->regs + reg + UNIPHIER_GPIO_PORT_DIR);
464 }
465
466 writel(*val++, priv->regs + UNIPHIER_GPIO_IRQ_EN);
467 writel(*val++, priv->regs + UNIPHIER_GPIO_IRQ_MODE);
468 writel(*val++, priv->regs + UNIPHIER_GPIO_IRQ_FLT_EN);
469
470 uniphier_gpio_hw_init(priv);
471
472 return 0;
473 }
474
475 static const struct dev_pm_ops uniphier_gpio_pm_ops = {
476 SET_LATE_SYSTEM_SLEEP_PM_OPS(uniphier_gpio_suspend,
477 uniphier_gpio_resume)
478 };
479
480 static const struct of_device_id uniphier_gpio_match[] = {
481 { .compatible = "socionext,uniphier-gpio" },
482 { /* sentinel */ }
483 };
484 MODULE_DEVICE_TABLE(of, uniphier_gpio_match);
485
486 static struct platform_driver uniphier_gpio_driver = {
487 .probe = uniphier_gpio_probe,
488 .remove = uniphier_gpio_remove,
489 .driver = {
490 .name = "uniphier-gpio",
491 .of_match_table = uniphier_gpio_match,
492 .pm = &uniphier_gpio_pm_ops,
493 },
494 };
495 module_platform_driver(uniphier_gpio_driver);
496
497 MODULE_AUTHOR("Masahiro Yamada <yamada.masahiro@socionext.com>");
498 MODULE_DESCRIPTION("UniPhier GPIO driver");
499 MODULE_LICENSE("GPL v2");
500