1 /*
2 * Copyright 2015 IBM Corp.
3 *
4 * Joel Stanley <joel@jms.id.au>
5 *
6 * This program is free software; you can redistribute it and/or
7 * modify it under the terms of the GNU General Public License
8 * as published by the Free Software Foundation; either version
9 * 2 of the License, or (at your option) any later version.
10 */
11
12 #include <linux/module.h>
13 #include <linux/kernel.h>
14 #include <linux/init.h>
15 #include <linux/io.h>
16 #include <linux/spinlock.h>
17 #include <linux/platform_device.h>
18 #include <linux/gpio/driver.h>
19 #include <linux/pinctrl/consumer.h>
20
21 struct aspeed_gpio {
22 struct gpio_chip chip;
23 spinlock_t lock;
24 void __iomem *base;
25 int irq;
26 };
27
28 struct aspeed_gpio_bank {
29 uint16_t val_regs;
30 uint16_t irq_regs;
31 const char names[4];
32 };
33
34 static const struct aspeed_gpio_bank aspeed_gpio_banks[] = {
35 {
36 .val_regs = 0x0000,
37 .irq_regs = 0x0008,
38 .names = { 'A', 'B', 'C', 'D' },
39 },
40 {
41 .val_regs = 0x0020,
42 .irq_regs = 0x0028,
43 .names = { 'E', 'F', 'G', 'H' },
44 },
45 {
46 .val_regs = 0x0070,
47 .irq_regs = 0x0098,
48 .names = { 'I', 'J', 'K', 'L' },
49 },
50 {
51 .val_regs = 0x0078,
52 .irq_regs = 0x00e8,
53 .names = { 'M', 'N', 'O', 'P' },
54 },
55 {
56 .val_regs = 0x0080,
57 .irq_regs = 0x0118,
58 .names = { 'Q', 'R', 'S', 'T' },
59 },
60 {
61 .val_regs = 0x0088,
62 .irq_regs = 0x0148,
63 .names = { 'U', 'V', 'W', 'X' },
64 },
65 /*
66 * A bank exists for { 'Y', 'Z', "AA", "AB" }, but is not implemented.
67 * Only half of GPIOs Y support interrupt configuration, and none of Z,
68 * AA or AB do as they are output only.
69 */
70 };
71
72 #define GPIO_BANK(x) ((x) >> 5)
73 #define GPIO_OFFSET(x) ((x) & 0x1f)
74 #define GPIO_BIT(x) BIT(GPIO_OFFSET(x))
75
76 #define GPIO_DATA 0x00
77 #define GPIO_DIR 0x04
78
79 #define GPIO_IRQ_ENABLE 0x00
80 #define GPIO_IRQ_TYPE0 0x04
81 #define GPIO_IRQ_TYPE1 0x08
82 #define GPIO_IRQ_TYPE2 0x0c
83 #define GPIO_IRQ_STATUS 0x10
84
to_bank(unsigned int offset)85 static const struct aspeed_gpio_bank *to_bank(unsigned int offset)
86 {
87 unsigned int bank = GPIO_BANK(offset);
88
89 WARN_ON(bank > ARRAY_SIZE(aspeed_gpio_banks));
90 return &aspeed_gpio_banks[bank];
91 }
92
bank_val_reg(struct aspeed_gpio * gpio,const struct aspeed_gpio_bank * bank,unsigned int reg)93 static void __iomem *bank_val_reg(struct aspeed_gpio *gpio,
94 const struct aspeed_gpio_bank *bank,
95 unsigned int reg)
96 {
97 return gpio->base + bank->val_regs + reg;
98 }
99
bank_irq_reg(struct aspeed_gpio * gpio,const struct aspeed_gpio_bank * bank,unsigned int reg)100 static void __iomem *bank_irq_reg(struct aspeed_gpio *gpio,
101 const struct aspeed_gpio_bank *bank,
102 unsigned int reg)
103 {
104 return gpio->base + bank->irq_regs + reg;
105 }
106
aspeed_gpio_get(struct gpio_chip * gc,unsigned int offset)107 static int aspeed_gpio_get(struct gpio_chip *gc, unsigned int offset)
108 {
109 struct aspeed_gpio *gpio = gpiochip_get_data(gc);
110 const struct aspeed_gpio_bank *bank = to_bank(offset);
111
112 return !!(ioread32(bank_val_reg(gpio, bank, GPIO_DATA))
113 & GPIO_BIT(offset));
114 }
115
__aspeed_gpio_set(struct gpio_chip * gc,unsigned int offset,int val)116 static void __aspeed_gpio_set(struct gpio_chip *gc, unsigned int offset,
117 int val)
118 {
119 struct aspeed_gpio *gpio = gpiochip_get_data(gc);
120 const struct aspeed_gpio_bank *bank = to_bank(offset);
121 void __iomem *addr;
122 u32 reg;
123
124 addr = bank_val_reg(gpio, bank, GPIO_DATA);
125 reg = ioread32(addr);
126
127 if (val)
128 reg |= GPIO_BIT(offset);
129 else
130 reg &= ~GPIO_BIT(offset);
131
132 iowrite32(reg, addr);
133 }
134
aspeed_gpio_set(struct gpio_chip * gc,unsigned int offset,int val)135 static void aspeed_gpio_set(struct gpio_chip *gc, unsigned int offset,
136 int val)
137 {
138 struct aspeed_gpio *gpio = gpiochip_get_data(gc);
139 unsigned long flags;
140
141 spin_lock_irqsave(&gpio->lock, flags);
142
143 __aspeed_gpio_set(gc, offset, val);
144
145 spin_unlock_irqrestore(&gpio->lock, flags);
146 }
147
aspeed_gpio_dir_in(struct gpio_chip * gc,unsigned int offset)148 static int aspeed_gpio_dir_in(struct gpio_chip *gc, unsigned int offset)
149 {
150 struct aspeed_gpio *gpio = gpiochip_get_data(gc);
151 const struct aspeed_gpio_bank *bank = to_bank(offset);
152 unsigned long flags;
153 u32 reg;
154
155 spin_lock_irqsave(&gpio->lock, flags);
156
157 reg = ioread32(bank_val_reg(gpio, bank, GPIO_DIR));
158 iowrite32(reg & ~GPIO_BIT(offset), bank_val_reg(gpio, bank, GPIO_DIR));
159
160 spin_unlock_irqrestore(&gpio->lock, flags);
161
162 return 0;
163 }
164
aspeed_gpio_dir_out(struct gpio_chip * gc,unsigned int offset,int val)165 static int aspeed_gpio_dir_out(struct gpio_chip *gc,
166 unsigned int offset, int val)
167 {
168 struct aspeed_gpio *gpio = gpiochip_get_data(gc);
169 const struct aspeed_gpio_bank *bank = to_bank(offset);
170 unsigned long flags;
171 u32 reg;
172
173 spin_lock_irqsave(&gpio->lock, flags);
174
175 reg = ioread32(bank_val_reg(gpio, bank, GPIO_DIR));
176 iowrite32(reg | GPIO_BIT(offset), bank_val_reg(gpio, bank, GPIO_DIR));
177
178 __aspeed_gpio_set(gc, offset, val);
179
180 spin_unlock_irqrestore(&gpio->lock, flags);
181
182 return 0;
183 }
184
aspeed_gpio_get_direction(struct gpio_chip * gc,unsigned int offset)185 static int aspeed_gpio_get_direction(struct gpio_chip *gc, unsigned int offset)
186 {
187 struct aspeed_gpio *gpio = gpiochip_get_data(gc);
188 const struct aspeed_gpio_bank *bank = to_bank(offset);
189 unsigned long flags;
190 u32 val;
191
192 spin_lock_irqsave(&gpio->lock, flags);
193
194 val = ioread32(bank_val_reg(gpio, bank, GPIO_DIR)) & GPIO_BIT(offset);
195
196 spin_unlock_irqrestore(&gpio->lock, flags);
197
198 return !val;
199
200 }
201
irqd_to_aspeed_gpio_data(struct irq_data * d,struct aspeed_gpio ** gpio,const struct aspeed_gpio_bank ** bank,u32 * bit)202 static inline int irqd_to_aspeed_gpio_data(struct irq_data *d,
203 struct aspeed_gpio **gpio,
204 const struct aspeed_gpio_bank **bank,
205 u32 *bit)
206 {
207 int offset;
208
209 offset = irqd_to_hwirq(d);
210
211 *gpio = irq_data_get_irq_chip_data(d);
212 *bank = to_bank(offset);
213 *bit = GPIO_BIT(offset);
214
215 return 0;
216 }
217
aspeed_gpio_irq_ack(struct irq_data * d)218 static void aspeed_gpio_irq_ack(struct irq_data *d)
219 {
220 const struct aspeed_gpio_bank *bank;
221 struct aspeed_gpio *gpio;
222 unsigned long flags;
223 void __iomem *status_addr;
224 u32 bit;
225 int rc;
226
227 rc = irqd_to_aspeed_gpio_data(d, &gpio, &bank, &bit);
228 if (rc)
229 return;
230
231 status_addr = bank_irq_reg(gpio, bank, GPIO_IRQ_STATUS);
232
233 spin_lock_irqsave(&gpio->lock, flags);
234 iowrite32(bit, status_addr);
235 spin_unlock_irqrestore(&gpio->lock, flags);
236 }
237
aspeed_gpio_irq_set_mask(struct irq_data * d,bool set)238 static void aspeed_gpio_irq_set_mask(struct irq_data *d, bool set)
239 {
240 const struct aspeed_gpio_bank *bank;
241 struct aspeed_gpio *gpio;
242 unsigned long flags;
243 u32 reg, bit;
244 void __iomem *addr;
245 int rc;
246
247 rc = irqd_to_aspeed_gpio_data(d, &gpio, &bank, &bit);
248 if (rc)
249 return;
250
251 addr = bank_irq_reg(gpio, bank, GPIO_IRQ_ENABLE);
252
253 spin_lock_irqsave(&gpio->lock, flags);
254
255 reg = ioread32(addr);
256 if (set)
257 reg |= bit;
258 else
259 reg &= bit;
260 iowrite32(reg, addr);
261
262 spin_unlock_irqrestore(&gpio->lock, flags);
263 }
264
aspeed_gpio_irq_mask(struct irq_data * d)265 static void aspeed_gpio_irq_mask(struct irq_data *d)
266 {
267 aspeed_gpio_irq_set_mask(d, false);
268 }
269
aspeed_gpio_irq_unmask(struct irq_data * d)270 static void aspeed_gpio_irq_unmask(struct irq_data *d)
271 {
272 aspeed_gpio_irq_set_mask(d, true);
273 }
274
aspeed_gpio_set_type(struct irq_data * d,unsigned int type)275 static int aspeed_gpio_set_type(struct irq_data *d, unsigned int type)
276 {
277 u32 type0 = 0;
278 u32 type1 = 0;
279 u32 type2 = 0;
280 u32 bit, reg;
281 const struct aspeed_gpio_bank *bank;
282 irq_flow_handler_t handler;
283 struct aspeed_gpio *gpio;
284 unsigned long flags;
285 void __iomem *addr;
286 int rc;
287
288 rc = irqd_to_aspeed_gpio_data(d, &gpio, &bank, &bit);
289 if (rc)
290 return -EINVAL;
291
292 switch (type & IRQ_TYPE_SENSE_MASK) {
293 case IRQ_TYPE_EDGE_BOTH:
294 type2 |= bit;
295 case IRQ_TYPE_EDGE_RISING:
296 type0 |= bit;
297 case IRQ_TYPE_EDGE_FALLING:
298 handler = handle_edge_irq;
299 break;
300 case IRQ_TYPE_LEVEL_HIGH:
301 type0 |= bit;
302 case IRQ_TYPE_LEVEL_LOW:
303 type1 |= bit;
304 handler = handle_level_irq;
305 break;
306 default:
307 return -EINVAL;
308 }
309
310 spin_lock_irqsave(&gpio->lock, flags);
311
312 addr = bank_irq_reg(gpio, bank, GPIO_IRQ_TYPE0);
313 reg = ioread32(addr);
314 reg = (reg & ~bit) | type0;
315 iowrite32(reg, addr);
316
317 addr = bank_irq_reg(gpio, bank, GPIO_IRQ_TYPE1);
318 reg = ioread32(addr);
319 reg = (reg & ~bit) | type1;
320 iowrite32(reg, addr);
321
322 addr = bank_irq_reg(gpio, bank, GPIO_IRQ_TYPE2);
323 reg = ioread32(addr);
324 reg = (reg & ~bit) | type2;
325 iowrite32(reg, addr);
326
327 spin_unlock_irqrestore(&gpio->lock, flags);
328
329 irq_set_handler_locked(d, handler);
330
331 return 0;
332 }
333
aspeed_gpio_irq_handler(struct irq_desc * desc)334 static void aspeed_gpio_irq_handler(struct irq_desc *desc)
335 {
336 struct gpio_chip *gc = irq_desc_get_handler_data(desc);
337 struct irq_chip *ic = irq_desc_get_chip(desc);
338 struct aspeed_gpio *data = gpiochip_get_data(gc);
339 unsigned int i, p, girq;
340 unsigned long reg;
341
342 chained_irq_enter(ic, desc);
343
344 for (i = 0; i < ARRAY_SIZE(aspeed_gpio_banks); i++) {
345 const struct aspeed_gpio_bank *bank = &aspeed_gpio_banks[i];
346
347 reg = ioread32(bank_irq_reg(data, bank, GPIO_IRQ_STATUS));
348
349 for_each_set_bit(p, ®, 32) {
350 girq = irq_find_mapping(gc->irqdomain, i * 32 + p);
351 generic_handle_irq(girq);
352 }
353
354 }
355
356 chained_irq_exit(ic, desc);
357 }
358
359 static struct irq_chip aspeed_gpio_irqchip = {
360 .name = "aspeed-gpio",
361 .irq_ack = aspeed_gpio_irq_ack,
362 .irq_mask = aspeed_gpio_irq_mask,
363 .irq_unmask = aspeed_gpio_irq_unmask,
364 .irq_set_type = aspeed_gpio_set_type,
365 };
366
aspeed_gpio_setup_irqs(struct aspeed_gpio * gpio,struct platform_device * pdev)367 static int aspeed_gpio_setup_irqs(struct aspeed_gpio *gpio,
368 struct platform_device *pdev)
369 {
370 int rc;
371
372 rc = platform_get_irq(pdev, 0);
373 if (rc < 0)
374 return rc;
375
376 gpio->irq = rc;
377
378 rc = gpiochip_irqchip_add(&gpio->chip, &aspeed_gpio_irqchip,
379 0, handle_bad_irq, IRQ_TYPE_NONE);
380 if (rc) {
381 dev_info(&pdev->dev, "Could not add irqchip\n");
382 return rc;
383 }
384
385 gpiochip_set_chained_irqchip(&gpio->chip, &aspeed_gpio_irqchip,
386 gpio->irq, aspeed_gpio_irq_handler);
387
388 return 0;
389 }
390
aspeed_gpio_request(struct gpio_chip * chip,unsigned int offset)391 static int aspeed_gpio_request(struct gpio_chip *chip, unsigned int offset)
392 {
393 return pinctrl_request_gpio(chip->base + offset);
394 }
395
aspeed_gpio_free(struct gpio_chip * chip,unsigned int offset)396 static void aspeed_gpio_free(struct gpio_chip *chip, unsigned int offset)
397 {
398 pinctrl_free_gpio(chip->base + offset);
399 }
400
aspeed_gpio_probe(struct platform_device * pdev)401 static int __init aspeed_gpio_probe(struct platform_device *pdev)
402 {
403 struct aspeed_gpio *gpio;
404 struct resource *res;
405 int rc;
406
407 gpio = devm_kzalloc(&pdev->dev, sizeof(*gpio), GFP_KERNEL);
408 if (!gpio)
409 return -ENOMEM;
410
411 res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
412 gpio->base = devm_ioremap_resource(&pdev->dev, res);
413 if (IS_ERR(gpio->base))
414 return PTR_ERR(gpio->base);
415
416 spin_lock_init(&gpio->lock);
417
418 gpio->chip.ngpio = ARRAY_SIZE(aspeed_gpio_banks) * 32;
419
420 gpio->chip.parent = &pdev->dev;
421 gpio->chip.direction_input = aspeed_gpio_dir_in;
422 gpio->chip.direction_output = aspeed_gpio_dir_out;
423 gpio->chip.get_direction = aspeed_gpio_get_direction;
424 gpio->chip.request = aspeed_gpio_request;
425 gpio->chip.free = aspeed_gpio_free;
426 gpio->chip.get = aspeed_gpio_get;
427 gpio->chip.set = aspeed_gpio_set;
428 gpio->chip.label = dev_name(&pdev->dev);
429 gpio->chip.base = -1;
430
431 rc = devm_gpiochip_add_data(&pdev->dev, &gpio->chip, gpio);
432 if (rc < 0)
433 return rc;
434
435 return aspeed_gpio_setup_irqs(gpio, pdev);
436 }
437
438 static const struct of_device_id aspeed_gpio_of_table[] = {
439 { .compatible = "aspeed,ast2400-gpio" },
440 { .compatible = "aspeed,ast2500-gpio" },
441 {}
442 };
443 MODULE_DEVICE_TABLE(of, aspeed_gpio_of_table);
444
445 static struct platform_driver aspeed_gpio_driver = {
446 .driver = {
447 .name = KBUILD_MODNAME,
448 .of_match_table = aspeed_gpio_of_table,
449 },
450 };
451
452 module_platform_driver_probe(aspeed_gpio_driver, aspeed_gpio_probe);
453
454 MODULE_DESCRIPTION("Aspeed GPIO Driver");
455 MODULE_LICENSE("GPL");
456