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1d09aaa6 MN |
1 | /* |
2 | * GPIO controller driver for Intel Lynxpoint PCH chipset> | |
3 | * Copyright (c) 2012, Intel Corporation. | |
4 | * | |
5 | * Author: Mathias Nyman <mathias.nyman@linux.intel.com> | |
6 | * | |
7 | * This program is free software; you can redistribute it and/or modify it | |
8 | * under the terms and conditions of the GNU General Public License, | |
9 | * version 2, as published by the Free Software Foundation. | |
10 | * | |
11 | * This program is distributed in the hope it will be useful, but WITHOUT | |
12 | * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or | |
13 | * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for | |
14 | * more details. | |
15 | * | |
16 | * You should have received a copy of the GNU General Public License along with | |
17 | * this program; if not, write to the Free Software Foundation, Inc., | |
18 | * 51 Franklin St - Fifth Floor, Boston, MA 02110-1301 USA. | |
19 | * | |
20 | */ | |
21 | ||
22 | #include <linux/kernel.h> | |
23 | #include <linux/module.h> | |
24 | #include <linux/init.h> | |
25 | #include <linux/types.h> | |
26 | #include <linux/bitops.h> | |
27 | #include <linux/interrupt.h> | |
28 | #include <linux/irq.h> | |
29 | #include <linux/gpio.h> | |
30 | #include <linux/irqdomain.h> | |
31 | #include <linux/slab.h> | |
32 | #include <linux/acpi.h> | |
33 | #include <linux/platform_device.h> | |
34 | #include <linux/pm_runtime.h> | |
977d16b8 | 35 | #include <linux/io.h> |
1d09aaa6 MN |
36 | |
37 | /* LynxPoint chipset has support for 94 gpio pins */ | |
38 | ||
39 | #define LP_NUM_GPIO 94 | |
40 | ||
41 | /* Bitmapped register offsets */ | |
42 | #define LP_ACPI_OWNED 0x00 /* Bitmap, set by bios, 0: pin reserved for ACPI */ | |
43 | #define LP_GC 0x7C /* set APIC IRQ to IRQ14 or IRQ15 for all pins */ | |
44 | #define LP_INT_STAT 0x80 | |
45 | #define LP_INT_ENABLE 0x90 | |
46 | ||
47 | /* Each pin has two 32 bit config registers, starting at 0x100 */ | |
48 | #define LP_CONFIG1 0x100 | |
49 | #define LP_CONFIG2 0x104 | |
50 | ||
51 | /* LP_CONFIG1 reg bits */ | |
52 | #define OUT_LVL_BIT BIT(31) | |
53 | #define IN_LVL_BIT BIT(30) | |
54 | #define TRIG_SEL_BIT BIT(4) /* 0: Edge, 1: Level */ | |
55 | #define INT_INV_BIT BIT(3) /* Invert interrupt triggering */ | |
56 | #define DIR_BIT BIT(2) /* 0: Output, 1: Input */ | |
57 | #define USE_SEL_BIT BIT(0) /* 0: Native, 1: GPIO */ | |
58 | ||
59 | /* LP_CONFIG2 reg bits */ | |
60 | #define GPINDIS_BIT BIT(2) /* disable input sensing */ | |
61 | #define GPIWP_BIT (BIT(0) | BIT(1)) /* weak pull options */ | |
62 | ||
63 | struct lp_gpio { | |
64 | struct gpio_chip chip; | |
65 | struct irq_domain *domain; | |
66 | struct platform_device *pdev; | |
67 | spinlock_t lock; | |
68 | unsigned long reg_base; | |
69 | }; | |
70 | ||
71 | /* | |
72 | * Lynxpoint gpios are controlled through both bitmapped registers and | |
73 | * per gpio specific registers. The bitmapped registers are in chunks of | |
74 | * 3 x 32bit registers to cover all 94 gpios | |
75 | * | |
76 | * per gpio specific registers consist of two 32bit registers per gpio | |
77 | * (LP_CONFIG1 and LP_CONFIG2), with 94 gpios there's a total of | |
78 | * 188 config registes. | |
79 | * | |
80 | * A simplified view of the register layout look like this: | |
81 | * | |
82 | * LP_ACPI_OWNED[31:0] gpio ownerships for gpios 0-31 (bitmapped registers) | |
83 | * LP_ACPI_OWNED[63:32] gpio ownerships for gpios 32-63 | |
84 | * LP_ACPI_OWNED[94:64] gpio ownerships for gpios 63-94 | |
85 | * ... | |
86 | * LP_INT_ENABLE[31:0] ... | |
87 | * LP_INT_ENABLE[63:31] ... | |
88 | * LP_INT_ENABLE[94:64] ... | |
89 | * LP0_CONFIG1 (gpio 0) config1 reg for gpio 0 (per gpio registers) | |
90 | * LP0_CONFIG2 (gpio 0) config2 reg for gpio 0 | |
91 | * LP1_CONFIG1 (gpio 1) config1 reg for gpio 1 | |
92 | * LP1_CONFIG2 (gpio 1) config2 reg for gpio 1 | |
93 | * LP2_CONFIG1 (gpio 2) ... | |
94 | * LP2_CONFIG2 (gpio 2) ... | |
95 | * ... | |
96 | * LP94_CONFIG1 (gpio 94) ... | |
97 | * LP94_CONFIG2 (gpio 94) ... | |
98 | */ | |
99 | ||
100 | static unsigned long lp_gpio_reg(struct gpio_chip *chip, unsigned offset, | |
101 | int reg) | |
102 | { | |
103 | struct lp_gpio *lg = container_of(chip, struct lp_gpio, chip); | |
104 | int reg_offset; | |
105 | ||
106 | if (reg == LP_CONFIG1 || reg == LP_CONFIG2) | |
107 | /* per gpio specific config registers */ | |
108 | reg_offset = offset * 8; | |
109 | else | |
110 | /* bitmapped registers */ | |
111 | reg_offset = (offset / 32) * 4; | |
112 | ||
113 | return lg->reg_base + reg + reg_offset; | |
114 | } | |
115 | ||
116 | static int lp_gpio_request(struct gpio_chip *chip, unsigned offset) | |
117 | { | |
118 | struct lp_gpio *lg = container_of(chip, struct lp_gpio, chip); | |
119 | unsigned long reg = lp_gpio_reg(chip, offset, LP_CONFIG1); | |
120 | unsigned long conf2 = lp_gpio_reg(chip, offset, LP_CONFIG2); | |
121 | unsigned long acpi_use = lp_gpio_reg(chip, offset, LP_ACPI_OWNED); | |
122 | ||
123 | pm_runtime_get(&lg->pdev->dev); /* should we put if failed */ | |
124 | ||
125 | /* Fail if BIOS reserved pin for ACPI use */ | |
126 | if (!(inl(acpi_use) & BIT(offset % 32))) { | |
127 | dev_err(&lg->pdev->dev, "gpio %d reserved for ACPI\n", offset); | |
128 | return -EBUSY; | |
129 | } | |
130 | /* Fail if pin is in alternate function mode (not GPIO mode) */ | |
131 | if (!(inl(reg) & USE_SEL_BIT)) | |
132 | return -ENODEV; | |
133 | ||
134 | /* enable input sensing */ | |
135 | outl(inl(conf2) & ~GPINDIS_BIT, conf2); | |
136 | ||
137 | ||
138 | return 0; | |
139 | } | |
140 | ||
141 | static void lp_gpio_free(struct gpio_chip *chip, unsigned offset) | |
142 | { | |
143 | struct lp_gpio *lg = container_of(chip, struct lp_gpio, chip); | |
144 | unsigned long conf2 = lp_gpio_reg(chip, offset, LP_CONFIG2); | |
145 | ||
146 | /* disable input sensing */ | |
147 | outl(inl(conf2) | GPINDIS_BIT, conf2); | |
148 | ||
149 | pm_runtime_put(&lg->pdev->dev); | |
150 | } | |
151 | ||
152 | static int lp_irq_type(struct irq_data *d, unsigned type) | |
153 | { | |
154 | struct lp_gpio *lg = irq_data_get_irq_chip_data(d); | |
155 | u32 hwirq = irqd_to_hwirq(d); | |
156 | unsigned long flags; | |
157 | u32 value; | |
158 | unsigned long reg = lp_gpio_reg(&lg->chip, hwirq, LP_CONFIG1); | |
159 | ||
160 | if (hwirq >= lg->chip.ngpio) | |
161 | return -EINVAL; | |
162 | ||
163 | spin_lock_irqsave(&lg->lock, flags); | |
164 | value = inl(reg); | |
165 | ||
166 | /* set both TRIG_SEL and INV bits to 0 for rising edge */ | |
167 | if (type & IRQ_TYPE_EDGE_RISING) | |
168 | value &= ~(TRIG_SEL_BIT | INT_INV_BIT); | |
169 | ||
170 | /* TRIG_SEL bit 0, INV bit 1 for falling edge */ | |
171 | if (type & IRQ_TYPE_EDGE_FALLING) | |
172 | value = (value | INT_INV_BIT) & ~TRIG_SEL_BIT; | |
173 | ||
174 | /* TRIG_SEL bit 1, INV bit 0 for level low */ | |
175 | if (type & IRQ_TYPE_LEVEL_LOW) | |
176 | value = (value | TRIG_SEL_BIT) & ~INT_INV_BIT; | |
177 | ||
178 | /* TRIG_SEL bit 1, INV bit 1 for level high */ | |
179 | if (type & IRQ_TYPE_LEVEL_HIGH) | |
180 | value |= TRIG_SEL_BIT | INT_INV_BIT; | |
181 | ||
182 | outl(value, reg); | |
183 | spin_unlock_irqrestore(&lg->lock, flags); | |
184 | ||
185 | return 0; | |
186 | } | |
187 | ||
188 | static int lp_gpio_get(struct gpio_chip *chip, unsigned offset) | |
189 | { | |
190 | unsigned long reg = lp_gpio_reg(chip, offset, LP_CONFIG1); | |
191 | return inl(reg) & IN_LVL_BIT; | |
192 | } | |
193 | ||
194 | static void lp_gpio_set(struct gpio_chip *chip, unsigned offset, int value) | |
195 | { | |
196 | struct lp_gpio *lg = container_of(chip, struct lp_gpio, chip); | |
197 | unsigned long reg = lp_gpio_reg(chip, offset, LP_CONFIG1); | |
198 | unsigned long flags; | |
199 | ||
200 | spin_lock_irqsave(&lg->lock, flags); | |
201 | ||
202 | if (value) | |
203 | outl(inl(reg) | OUT_LVL_BIT, reg); | |
204 | else | |
205 | outl(inl(reg) & ~OUT_LVL_BIT, reg); | |
206 | ||
207 | spin_unlock_irqrestore(&lg->lock, flags); | |
208 | } | |
209 | ||
210 | static int lp_gpio_direction_input(struct gpio_chip *chip, unsigned offset) | |
211 | { | |
212 | struct lp_gpio *lg = container_of(chip, struct lp_gpio, chip); | |
213 | unsigned long reg = lp_gpio_reg(chip, offset, LP_CONFIG1); | |
214 | unsigned long flags; | |
215 | ||
216 | spin_lock_irqsave(&lg->lock, flags); | |
217 | outl(inl(reg) | DIR_BIT, reg); | |
218 | spin_unlock_irqrestore(&lg->lock, flags); | |
219 | ||
220 | return 0; | |
221 | } | |
222 | ||
223 | static int lp_gpio_direction_output(struct gpio_chip *chip, | |
224 | unsigned offset, int value) | |
225 | { | |
226 | struct lp_gpio *lg = container_of(chip, struct lp_gpio, chip); | |
227 | unsigned long reg = lp_gpio_reg(chip, offset, LP_CONFIG1); | |
228 | unsigned long flags; | |
229 | ||
230 | lp_gpio_set(chip, offset, value); | |
231 | ||
232 | spin_lock_irqsave(&lg->lock, flags); | |
233 | outl(inl(reg) & ~DIR_BIT, reg); | |
234 | spin_unlock_irqrestore(&lg->lock, flags); | |
235 | ||
236 | return 0; | |
237 | } | |
238 | ||
239 | static int lp_gpio_to_irq(struct gpio_chip *chip, unsigned offset) | |
240 | { | |
241 | struct lp_gpio *lg = container_of(chip, struct lp_gpio, chip); | |
242 | return irq_create_mapping(lg->domain, offset); | |
243 | } | |
244 | ||
245 | static void lp_gpio_irq_handler(unsigned irq, struct irq_desc *desc) | |
246 | { | |
247 | struct irq_data *data = irq_desc_get_irq_data(desc); | |
248 | struct lp_gpio *lg = irq_data_get_irq_handler_data(data); | |
249 | struct irq_chip *chip = irq_data_get_irq_chip(data); | |
250 | u32 base, pin, mask; | |
03d152d5 | 251 | unsigned long reg, ena, pending; |
1d09aaa6 MN |
252 | unsigned virq; |
253 | ||
254 | /* check from GPIO controller which pin triggered the interrupt */ | |
255 | for (base = 0; base < lg->chip.ngpio; base += 32) { | |
256 | reg = lp_gpio_reg(&lg->chip, base, LP_INT_STAT); | |
03d152d5 | 257 | ena = lp_gpio_reg(&lg->chip, base, LP_INT_ENABLE); |
1d09aaa6 | 258 | |
03d152d5 | 259 | while ((pending = (inl(reg) & inl(ena)))) { |
1d09aaa6 MN |
260 | pin = __ffs(pending); |
261 | mask = BIT(pin); | |
262 | /* Clear before handling so we don't lose an edge */ | |
263 | outl(mask, reg); | |
264 | virq = irq_find_mapping(lg->domain, base + pin); | |
265 | generic_handle_irq(virq); | |
266 | } | |
267 | } | |
268 | chip->irq_eoi(data); | |
269 | } | |
270 | ||
271 | static void lp_irq_unmask(struct irq_data *d) | |
272 | { | |
273 | } | |
274 | ||
275 | static void lp_irq_mask(struct irq_data *d) | |
276 | { | |
277 | } | |
278 | ||
279 | static void lp_irq_enable(struct irq_data *d) | |
280 | { | |
281 | struct lp_gpio *lg = irq_data_get_irq_chip_data(d); | |
282 | u32 hwirq = irqd_to_hwirq(d); | |
283 | unsigned long reg = lp_gpio_reg(&lg->chip, hwirq, LP_INT_ENABLE); | |
284 | unsigned long flags; | |
285 | ||
286 | spin_lock_irqsave(&lg->lock, flags); | |
287 | outl(inl(reg) | BIT(hwirq % 32), reg); | |
288 | spin_unlock_irqrestore(&lg->lock, flags); | |
289 | } | |
290 | ||
291 | static void lp_irq_disable(struct irq_data *d) | |
292 | { | |
293 | struct lp_gpio *lg = irq_data_get_irq_chip_data(d); | |
294 | u32 hwirq = irqd_to_hwirq(d); | |
295 | unsigned long reg = lp_gpio_reg(&lg->chip, hwirq, LP_INT_ENABLE); | |
296 | unsigned long flags; | |
297 | ||
298 | spin_lock_irqsave(&lg->lock, flags); | |
299 | outl(inl(reg) & ~BIT(hwirq % 32), reg); | |
300 | spin_unlock_irqrestore(&lg->lock, flags); | |
301 | } | |
302 | ||
303 | static struct irq_chip lp_irqchip = { | |
304 | .name = "LP-GPIO", | |
305 | .irq_mask = lp_irq_mask, | |
306 | .irq_unmask = lp_irq_unmask, | |
307 | .irq_enable = lp_irq_enable, | |
308 | .irq_disable = lp_irq_disable, | |
309 | .irq_set_type = lp_irq_type, | |
310 | .flags = IRQCHIP_SKIP_SET_WAKE, | |
311 | }; | |
312 | ||
313 | static void lp_gpio_irq_init_hw(struct lp_gpio *lg) | |
314 | { | |
315 | unsigned long reg; | |
316 | unsigned base; | |
317 | ||
318 | for (base = 0; base < lg->chip.ngpio; base += 32) { | |
319 | /* disable gpio pin interrupts */ | |
320 | reg = lp_gpio_reg(&lg->chip, base, LP_INT_ENABLE); | |
321 | outl(0, reg); | |
322 | /* Clear interrupt status register */ | |
323 | reg = lp_gpio_reg(&lg->chip, base, LP_INT_STAT); | |
324 | outl(0xffffffff, reg); | |
325 | } | |
326 | } | |
327 | ||
328 | static int lp_gpio_irq_map(struct irq_domain *d, unsigned int virq, | |
329 | irq_hw_number_t hw) | |
330 | { | |
331 | struct lp_gpio *lg = d->host_data; | |
332 | ||
333 | irq_set_chip_and_handler_name(virq, &lp_irqchip, handle_simple_irq, | |
334 | "demux"); | |
335 | irq_set_chip_data(virq, lg); | |
336 | irq_set_irq_type(virq, IRQ_TYPE_NONE); | |
337 | ||
338 | return 0; | |
339 | } | |
340 | ||
341 | static const struct irq_domain_ops lp_gpio_irq_ops = { | |
342 | .map = lp_gpio_irq_map, | |
343 | }; | |
344 | ||
345 | static int lp_gpio_probe(struct platform_device *pdev) | |
346 | { | |
347 | struct lp_gpio *lg; | |
348 | struct gpio_chip *gc; | |
349 | struct resource *io_rc, *irq_rc; | |
350 | struct device *dev = &pdev->dev; | |
351 | unsigned long reg_len; | |
352 | unsigned hwirq; | |
353 | int ret = -ENODEV; | |
354 | ||
355 | lg = devm_kzalloc(dev, sizeof(struct lp_gpio), GFP_KERNEL); | |
356 | if (!lg) { | |
357 | dev_err(dev, "can't allocate lp_gpio chip data\n"); | |
358 | return -ENOMEM; | |
359 | } | |
360 | ||
361 | lg->pdev = pdev; | |
362 | platform_set_drvdata(pdev, lg); | |
363 | ||
364 | io_rc = platform_get_resource(pdev, IORESOURCE_IO, 0); | |
365 | irq_rc = platform_get_resource(pdev, IORESOURCE_IRQ, 0); | |
366 | ||
367 | if (!io_rc) { | |
368 | dev_err(dev, "missing IO resources\n"); | |
369 | return -EINVAL; | |
370 | } | |
371 | ||
372 | lg->reg_base = io_rc->start; | |
373 | reg_len = resource_size(io_rc); | |
374 | ||
375 | if (!devm_request_region(dev, lg->reg_base, reg_len, "lp-gpio")) { | |
376 | dev_err(dev, "failed requesting IO region 0x%x\n", | |
377 | (unsigned int)lg->reg_base); | |
378 | return -EBUSY; | |
379 | } | |
380 | ||
381 | spin_lock_init(&lg->lock); | |
382 | ||
383 | gc = &lg->chip; | |
384 | gc->label = dev_name(dev); | |
385 | gc->owner = THIS_MODULE; | |
386 | gc->request = lp_gpio_request; | |
387 | gc->free = lp_gpio_free; | |
388 | gc->direction_input = lp_gpio_direction_input; | |
389 | gc->direction_output = lp_gpio_direction_output; | |
390 | gc->get = lp_gpio_get; | |
391 | gc->set = lp_gpio_set; | |
392 | gc->base = -1; | |
393 | gc->ngpio = LP_NUM_GPIO; | |
394 | gc->can_sleep = 0; | |
395 | gc->dev = dev; | |
396 | ||
397 | /* set up interrupts */ | |
398 | if (irq_rc && irq_rc->start) { | |
399 | hwirq = irq_rc->start; | |
400 | gc->to_irq = lp_gpio_to_irq; | |
401 | ||
402 | lg->domain = irq_domain_add_linear(NULL, LP_NUM_GPIO, | |
403 | &lp_gpio_irq_ops, lg); | |
404 | if (!lg->domain) | |
405 | return -ENXIO; | |
406 | ||
407 | lp_gpio_irq_init_hw(lg); | |
408 | ||
409 | irq_set_handler_data(hwirq, lg); | |
410 | irq_set_chained_handler(hwirq, lp_gpio_irq_handler); | |
411 | } | |
412 | ||
413 | ret = gpiochip_add(gc); | |
414 | if (ret) { | |
415 | dev_err(dev, "failed adding lp-gpio chip\n"); | |
416 | return ret; | |
417 | } | |
418 | pm_runtime_enable(dev); | |
419 | ||
420 | return 0; | |
421 | } | |
422 | ||
423 | static int lp_gpio_runtime_suspend(struct device *dev) | |
424 | { | |
425 | return 0; | |
426 | } | |
427 | ||
428 | static int lp_gpio_runtime_resume(struct device *dev) | |
429 | { | |
430 | return 0; | |
431 | } | |
432 | ||
433 | static const struct dev_pm_ops lp_gpio_pm_ops = { | |
434 | .runtime_suspend = lp_gpio_runtime_suspend, | |
435 | .runtime_resume = lp_gpio_runtime_resume, | |
436 | }; | |
437 | ||
438 | static const struct acpi_device_id lynxpoint_gpio_acpi_match[] = { | |
439 | { "INT33C7", 0 }, | |
440 | { } | |
441 | }; | |
442 | MODULE_DEVICE_TABLE(acpi, lynxpoint_gpio_acpi_match); | |
443 | ||
444 | static int lp_gpio_remove(struct platform_device *pdev) | |
445 | { | |
446 | struct lp_gpio *lg = platform_get_drvdata(pdev); | |
447 | int err; | |
b168386e | 448 | pm_runtime_disable(&pdev->dev); |
1d09aaa6 MN |
449 | err = gpiochip_remove(&lg->chip); |
450 | if (err) | |
451 | dev_warn(&pdev->dev, "failed to remove gpio_chip.\n"); | |
1d09aaa6 MN |
452 | return 0; |
453 | } | |
454 | ||
455 | static struct platform_driver lp_gpio_driver = { | |
456 | .probe = lp_gpio_probe, | |
457 | .remove = lp_gpio_remove, | |
458 | .driver = { | |
459 | .name = "lp_gpio", | |
460 | .owner = THIS_MODULE, | |
461 | .pm = &lp_gpio_pm_ops, | |
462 | .acpi_match_table = ACPI_PTR(lynxpoint_gpio_acpi_match), | |
463 | }, | |
464 | }; | |
465 | ||
466 | static int __init lp_gpio_init(void) | |
467 | { | |
468 | return platform_driver_register(&lp_gpio_driver); | |
469 | } | |
470 | ||
471 | subsys_initcall(lp_gpio_init); |