1 | // SPDX-License-Identifier: GPL-2.0+ |
2 | /* |
3 | * Intel ICH6-10, Series 5 and 6, Atom C2000 (Avoton/Rangeley) GPIO driver |
4 | * |
5 | * Copyright (C) 2010 Extreme Engineering Solutions. |
6 | */ |
7 | |
8 | #include <linux/bitops.h> |
9 | #include <linux/gpio/driver.h> |
10 | #include <linux/ioport.h> |
11 | #include <linux/mfd/lpc_ich.h> |
12 | #include <linux/module.h> |
13 | #include <linux/platform_device.h> |
14 | |
15 | #define DRV_NAME "gpio_ich" |
16 | |
17 | /* |
18 | * GPIO register offsets in GPIO I/O space. |
19 | * Each chunk of 32 GPIOs is manipulated via its own USE_SELx, IO_SELx, and |
20 | * LVLx registers. Logic in the read/write functions takes a register and |
21 | * an absolute bit number and determines the proper register offset and bit |
22 | * number in that register. For example, to read the value of GPIO bit 50 |
23 | * the code would access offset ichx_regs[2(=GPIO_LVL)][1(=50/32)], |
24 | * bit 18 (50%32). |
25 | */ |
26 | enum GPIO_REG { |
27 | GPIO_USE_SEL = 0, |
28 | GPIO_IO_SEL, |
29 | GPIO_LVL, |
30 | GPO_BLINK |
31 | }; |
32 | |
33 | static const u8 ichx_regs[4][3] = { |
34 | {0x00, 0x30, 0x40}, /* USE_SEL[1-3] offsets */ |
35 | {0x04, 0x34, 0x44}, /* IO_SEL[1-3] offsets */ |
36 | {0x0c, 0x38, 0x48}, /* LVL[1-3] offsets */ |
37 | {0x18, 0x18, 0x18}, /* BLINK offset */ |
38 | }; |
39 | |
40 | static const u8 ichx_reglen[3] = { |
41 | 0x30, 0x10, 0x10, |
42 | }; |
43 | |
44 | static const u8 avoton_regs[4][3] = { |
45 | {0x00, 0x80, 0x00}, |
46 | {0x04, 0x84, 0x00}, |
47 | {0x08, 0x88, 0x00}, |
48 | }; |
49 | |
50 | static const u8 avoton_reglen[3] = { |
51 | 0x10, 0x10, 0x00, |
52 | }; |
53 | |
54 | #define ICHX_WRITE(val, reg, base_res) outl(val, (reg) + (base_res)->start) |
55 | #define ICHX_READ(reg, base_res) inl((reg) + (base_res)->start) |
56 | |
57 | struct ichx_desc { |
58 | /* Max GPIO pins the chipset can have */ |
59 | uint ngpio; |
60 | |
61 | /* chipset registers */ |
62 | const u8 (*regs)[3]; |
63 | const u8 *reglen; |
64 | |
65 | /* GPO_BLINK is available on this chipset */ |
66 | bool have_blink; |
67 | |
68 | /* Whether the chipset has GPIO in GPE0_STS in the PM IO region */ |
69 | bool uses_gpe0; |
70 | |
71 | /* USE_SEL is bogus on some chipsets, eg 3100 */ |
72 | u32 use_sel_ignore[3]; |
73 | |
74 | /* Some chipsets have quirks, let these use their own request/get */ |
75 | int (*request)(struct gpio_chip *chip, unsigned int offset); |
76 | int (*get)(struct gpio_chip *chip, unsigned int offset); |
77 | |
78 | /* |
79 | * Some chipsets don't let reading output values on GPIO_LVL register |
80 | * this option allows driver caching written output values |
81 | */ |
82 | bool use_outlvl_cache; |
83 | }; |
84 | |
85 | static struct { |
86 | spinlock_t lock; |
87 | struct device *dev; |
88 | struct gpio_chip chip; |
89 | struct resource *gpio_base; /* GPIO IO base */ |
90 | struct resource *pm_base; /* Power Management IO base */ |
91 | struct ichx_desc *desc; /* Pointer to chipset-specific description */ |
92 | u32 orig_gpio_ctrl; /* Orig CTRL value, used to restore on exit */ |
93 | u8 use_gpio; /* Which GPIO groups are usable */ |
94 | int outlvl_cache[3]; /* cached output values */ |
95 | } ichx_priv; |
96 | |
97 | static int modparam_gpiobase = -1; /* dynamic */ |
98 | module_param_named(gpiobase, modparam_gpiobase, int, 0444); |
99 | MODULE_PARM_DESC(gpiobase, "The GPIO number base. -1 means dynamic, which is the default." ); |
100 | |
101 | static int ichx_write_bit(int reg, unsigned int nr, int val, int verify) |
102 | { |
103 | unsigned long flags; |
104 | u32 data, tmp; |
105 | int reg_nr = nr / 32; |
106 | int bit = nr & 0x1f; |
107 | |
108 | spin_lock_irqsave(&ichx_priv.lock, flags); |
109 | |
110 | if (reg == GPIO_LVL && ichx_priv.desc->use_outlvl_cache) |
111 | data = ichx_priv.outlvl_cache[reg_nr]; |
112 | else |
113 | data = ICHX_READ(ichx_priv.desc->regs[reg][reg_nr], |
114 | ichx_priv.gpio_base); |
115 | |
116 | if (val) |
117 | data |= BIT(bit); |
118 | else |
119 | data &= ~BIT(bit); |
120 | ICHX_WRITE(data, ichx_priv.desc->regs[reg][reg_nr], |
121 | ichx_priv.gpio_base); |
122 | if (reg == GPIO_LVL && ichx_priv.desc->use_outlvl_cache) |
123 | ichx_priv.outlvl_cache[reg_nr] = data; |
124 | |
125 | tmp = ICHX_READ(ichx_priv.desc->regs[reg][reg_nr], |
126 | ichx_priv.gpio_base); |
127 | |
128 | spin_unlock_irqrestore(lock: &ichx_priv.lock, flags); |
129 | |
130 | return (verify && data != tmp) ? -EPERM : 0; |
131 | } |
132 | |
133 | static int ichx_read_bit(int reg, unsigned int nr) |
134 | { |
135 | unsigned long flags; |
136 | u32 data; |
137 | int reg_nr = nr / 32; |
138 | int bit = nr & 0x1f; |
139 | |
140 | spin_lock_irqsave(&ichx_priv.lock, flags); |
141 | |
142 | data = ICHX_READ(ichx_priv.desc->regs[reg][reg_nr], |
143 | ichx_priv.gpio_base); |
144 | |
145 | if (reg == GPIO_LVL && ichx_priv.desc->use_outlvl_cache) |
146 | data = ichx_priv.outlvl_cache[reg_nr] | data; |
147 | |
148 | spin_unlock_irqrestore(lock: &ichx_priv.lock, flags); |
149 | |
150 | return !!(data & BIT(bit)); |
151 | } |
152 | |
153 | static bool ichx_gpio_check_available(struct gpio_chip *gpio, unsigned int nr) |
154 | { |
155 | return !!(ichx_priv.use_gpio & BIT(nr / 32)); |
156 | } |
157 | |
158 | static int ichx_gpio_get_direction(struct gpio_chip *gpio, unsigned int nr) |
159 | { |
160 | if (ichx_read_bit(reg: GPIO_IO_SEL, nr)) |
161 | return GPIO_LINE_DIRECTION_IN; |
162 | |
163 | return GPIO_LINE_DIRECTION_OUT; |
164 | } |
165 | |
166 | static int ichx_gpio_direction_input(struct gpio_chip *gpio, unsigned int nr) |
167 | { |
168 | /* |
169 | * Try setting pin as an input and verify it worked since many pins |
170 | * are output-only. |
171 | */ |
172 | return ichx_write_bit(reg: GPIO_IO_SEL, nr, val: 1, verify: 1); |
173 | } |
174 | |
175 | static int ichx_gpio_direction_output(struct gpio_chip *gpio, unsigned int nr, |
176 | int val) |
177 | { |
178 | /* Disable blink hardware which is available for GPIOs from 0 to 31. */ |
179 | if (nr < 32 && ichx_priv.desc->have_blink) |
180 | ichx_write_bit(reg: GPO_BLINK, nr, val: 0, verify: 0); |
181 | |
182 | /* Set GPIO output value. */ |
183 | ichx_write_bit(reg: GPIO_LVL, nr, val, verify: 0); |
184 | |
185 | /* |
186 | * Try setting pin as an output and verify it worked since many pins |
187 | * are input-only. |
188 | */ |
189 | return ichx_write_bit(reg: GPIO_IO_SEL, nr, val: 0, verify: 1); |
190 | } |
191 | |
192 | static int ichx_gpio_get(struct gpio_chip *chip, unsigned int nr) |
193 | { |
194 | return ichx_read_bit(reg: GPIO_LVL, nr); |
195 | } |
196 | |
197 | static int ich6_gpio_get(struct gpio_chip *chip, unsigned int nr) |
198 | { |
199 | unsigned long flags; |
200 | u32 data; |
201 | |
202 | /* |
203 | * GPI 0 - 15 need to be read from the power management registers on |
204 | * a ICH6/3100 bridge. |
205 | */ |
206 | if (nr < 16) { |
207 | if (!ichx_priv.pm_base) |
208 | return -ENXIO; |
209 | |
210 | spin_lock_irqsave(&ichx_priv.lock, flags); |
211 | |
212 | /* GPI 0 - 15 are latched, write 1 to clear*/ |
213 | ICHX_WRITE(BIT(16 + nr), 0, ichx_priv.pm_base); |
214 | data = ICHX_READ(0, ichx_priv.pm_base); |
215 | |
216 | spin_unlock_irqrestore(lock: &ichx_priv.lock, flags); |
217 | |
218 | return !!((data >> 16) & BIT(nr)); |
219 | } else { |
220 | return ichx_gpio_get(chip, nr); |
221 | } |
222 | } |
223 | |
224 | static int ichx_gpio_request(struct gpio_chip *chip, unsigned int nr) |
225 | { |
226 | if (!ichx_gpio_check_available(gpio: chip, nr)) |
227 | return -ENXIO; |
228 | |
229 | /* |
230 | * Note we assume the BIOS properly set a bridge's USE value. Some |
231 | * chips (eg Intel 3100) have bogus USE values though, so first see if |
232 | * the chipset's USE value can be trusted for this specific bit. |
233 | * If it can't be trusted, assume that the pin can be used as a GPIO. |
234 | */ |
235 | if (ichx_priv.desc->use_sel_ignore[nr / 32] & BIT(nr & 0x1f)) |
236 | return 0; |
237 | |
238 | return ichx_read_bit(reg: GPIO_USE_SEL, nr) ? 0 : -ENODEV; |
239 | } |
240 | |
241 | static int ich6_gpio_request(struct gpio_chip *chip, unsigned int nr) |
242 | { |
243 | /* |
244 | * Fixups for bits 16 and 17 are necessary on the Intel ICH6/3100 |
245 | * bridge as they are controlled by USE register bits 0 and 1. See |
246 | * "Table 704 GPIO_USE_SEL1 register" in the i3100 datasheet for |
247 | * additional info. |
248 | */ |
249 | if (nr == 16 || nr == 17) |
250 | nr -= 16; |
251 | |
252 | return ichx_gpio_request(chip, nr); |
253 | } |
254 | |
255 | static void ichx_gpio_set(struct gpio_chip *chip, unsigned int nr, int val) |
256 | { |
257 | ichx_write_bit(reg: GPIO_LVL, nr, val, verify: 0); |
258 | } |
259 | |
260 | static void ichx_gpiolib_setup(struct gpio_chip *chip) |
261 | { |
262 | chip->owner = THIS_MODULE; |
263 | chip->label = DRV_NAME; |
264 | chip->parent = ichx_priv.dev; |
265 | |
266 | /* Allow chip-specific overrides of request()/get() */ |
267 | chip->request = ichx_priv.desc->request ? |
268 | ichx_priv.desc->request : ichx_gpio_request; |
269 | chip->get = ichx_priv.desc->get ? |
270 | ichx_priv.desc->get : ichx_gpio_get; |
271 | |
272 | chip->set = ichx_gpio_set; |
273 | chip->get_direction = ichx_gpio_get_direction; |
274 | chip->direction_input = ichx_gpio_direction_input; |
275 | chip->direction_output = ichx_gpio_direction_output; |
276 | chip->base = modparam_gpiobase; |
277 | chip->ngpio = ichx_priv.desc->ngpio; |
278 | chip->can_sleep = false; |
279 | chip->dbg_show = NULL; |
280 | } |
281 | |
282 | /* ICH6-based, 631xesb-based */ |
283 | static struct ichx_desc ich6_desc = { |
284 | /* Bridges using the ICH6 controller need fixups for GPIO 0 - 17 */ |
285 | .request = ich6_gpio_request, |
286 | .get = ich6_gpio_get, |
287 | |
288 | /* GPIO 0-15 are read in the GPE0_STS PM register */ |
289 | .uses_gpe0 = true, |
290 | |
291 | .ngpio = 50, |
292 | .have_blink = true, |
293 | .regs = ichx_regs, |
294 | .reglen = ichx_reglen, |
295 | }; |
296 | |
297 | /* Intel 3100 */ |
298 | static struct ichx_desc i3100_desc = { |
299 | /* |
300 | * Bits 16,17, 20 of USE_SEL and bit 16 of USE_SEL2 always read 0 on |
301 | * the Intel 3100. See "Table 712. GPIO Summary Table" of 3100 |
302 | * Datasheet for more info. |
303 | */ |
304 | .use_sel_ignore = {0x00130000, 0x00010000, 0x0}, |
305 | |
306 | /* The 3100 needs fixups for GPIO 0 - 17 */ |
307 | .request = ich6_gpio_request, |
308 | .get = ich6_gpio_get, |
309 | |
310 | /* GPIO 0-15 are read in the GPE0_STS PM register */ |
311 | .uses_gpe0 = true, |
312 | |
313 | .ngpio = 50, |
314 | .regs = ichx_regs, |
315 | .reglen = ichx_reglen, |
316 | }; |
317 | |
318 | /* ICH7 and ICH8-based */ |
319 | static struct ichx_desc ich7_desc = { |
320 | .ngpio = 50, |
321 | .have_blink = true, |
322 | .regs = ichx_regs, |
323 | .reglen = ichx_reglen, |
324 | }; |
325 | |
326 | /* ICH9-based */ |
327 | static struct ichx_desc ich9_desc = { |
328 | .ngpio = 61, |
329 | .have_blink = true, |
330 | .regs = ichx_regs, |
331 | .reglen = ichx_reglen, |
332 | }; |
333 | |
334 | /* ICH10-based - Consumer/corporate versions have different amount of GPIO */ |
335 | static struct ichx_desc ich10_cons_desc = { |
336 | .ngpio = 61, |
337 | .have_blink = true, |
338 | .regs = ichx_regs, |
339 | .reglen = ichx_reglen, |
340 | }; |
341 | static struct ichx_desc ich10_corp_desc = { |
342 | .ngpio = 72, |
343 | .have_blink = true, |
344 | .regs = ichx_regs, |
345 | .reglen = ichx_reglen, |
346 | }; |
347 | |
348 | /* Intel 5 series, 6 series, 3400 series, and C200 series */ |
349 | static struct ichx_desc intel5_desc = { |
350 | .ngpio = 76, |
351 | .regs = ichx_regs, |
352 | .reglen = ichx_reglen, |
353 | }; |
354 | |
355 | /* Avoton */ |
356 | static struct ichx_desc avoton_desc = { |
357 | /* Avoton has only 59 GPIOs, but we assume the first set of register |
358 | * (Core) has 32 instead of 31 to keep gpio-ich compliance |
359 | */ |
360 | .ngpio = 60, |
361 | .regs = avoton_regs, |
362 | .reglen = avoton_reglen, |
363 | .use_outlvl_cache = true, |
364 | }; |
365 | |
366 | static int ichx_gpio_request_regions(struct device *dev, |
367 | struct resource *res_base, const char *name, u8 use_gpio) |
368 | { |
369 | int i; |
370 | |
371 | if (!res_base || !res_base->start || !res_base->end) |
372 | return -ENODEV; |
373 | |
374 | for (i = 0; i < ARRAY_SIZE(ichx_priv.desc->regs[0]); i++) { |
375 | if (!(use_gpio & BIT(i))) |
376 | continue; |
377 | if (!devm_request_region(dev, |
378 | res_base->start + ichx_priv.desc->regs[0][i], |
379 | ichx_priv.desc->reglen[i], name)) |
380 | return -EBUSY; |
381 | } |
382 | return 0; |
383 | } |
384 | |
385 | static int ichx_gpio_probe(struct platform_device *pdev) |
386 | { |
387 | struct device *dev = &pdev->dev; |
388 | struct lpc_ich_info *ich_info = dev_get_platdata(dev); |
389 | struct resource *res_base, *res_pm; |
390 | int err; |
391 | |
392 | if (!ich_info) |
393 | return -ENODEV; |
394 | |
395 | switch (ich_info->gpio_version) { |
396 | case ICH_I3100_GPIO: |
397 | ichx_priv.desc = &i3100_desc; |
398 | break; |
399 | case ICH_V5_GPIO: |
400 | ichx_priv.desc = &intel5_desc; |
401 | break; |
402 | case ICH_V6_GPIO: |
403 | ichx_priv.desc = &ich6_desc; |
404 | break; |
405 | case ICH_V7_GPIO: |
406 | ichx_priv.desc = &ich7_desc; |
407 | break; |
408 | case ICH_V9_GPIO: |
409 | ichx_priv.desc = &ich9_desc; |
410 | break; |
411 | case ICH_V10CORP_GPIO: |
412 | ichx_priv.desc = &ich10_corp_desc; |
413 | break; |
414 | case ICH_V10CONS_GPIO: |
415 | ichx_priv.desc = &ich10_cons_desc; |
416 | break; |
417 | case AVOTON_GPIO: |
418 | ichx_priv.desc = &avoton_desc; |
419 | break; |
420 | default: |
421 | return -ENODEV; |
422 | } |
423 | |
424 | ichx_priv.dev = dev; |
425 | spin_lock_init(&ichx_priv.lock); |
426 | |
427 | res_base = platform_get_resource(pdev, IORESOURCE_IO, ICH_RES_GPIO); |
428 | err = ichx_gpio_request_regions(dev, res_base, name: pdev->name, |
429 | use_gpio: ich_info->use_gpio); |
430 | if (err) |
431 | return err; |
432 | |
433 | ichx_priv.gpio_base = res_base; |
434 | ichx_priv.use_gpio = ich_info->use_gpio; |
435 | |
436 | /* |
437 | * If necessary, determine the I/O address of ACPI/power management |
438 | * registers which are needed to read the GPE0 register for GPI pins |
439 | * 0 - 15 on some chipsets. |
440 | */ |
441 | if (!ichx_priv.desc->uses_gpe0) |
442 | goto init; |
443 | |
444 | res_pm = platform_get_resource(pdev, IORESOURCE_IO, ICH_RES_GPE0); |
445 | if (!res_pm) { |
446 | dev_warn(dev, "ACPI BAR is unavailable, GPI 0 - 15 unavailable\n" ); |
447 | goto init; |
448 | } |
449 | |
450 | if (!devm_request_region(dev, res_pm->start, resource_size(res_pm), |
451 | pdev->name)) { |
452 | dev_warn(dev, "ACPI BAR is busy, GPI 0 - 15 unavailable\n" ); |
453 | goto init; |
454 | } |
455 | |
456 | ichx_priv.pm_base = res_pm; |
457 | |
458 | init: |
459 | ichx_gpiolib_setup(chip: &ichx_priv.chip); |
460 | err = devm_gpiochip_add_data(dev, &ichx_priv.chip, NULL); |
461 | if (err) { |
462 | dev_err(dev, "Failed to register GPIOs\n" ); |
463 | return err; |
464 | } |
465 | |
466 | dev_info(dev, "GPIO from %d to %d\n" , ichx_priv.chip.base, |
467 | ichx_priv.chip.base + ichx_priv.chip.ngpio - 1); |
468 | |
469 | return 0; |
470 | } |
471 | |
472 | static struct platform_driver ichx_gpio_driver = { |
473 | .driver = { |
474 | .name = DRV_NAME, |
475 | }, |
476 | .probe = ichx_gpio_probe, |
477 | }; |
478 | |
479 | module_platform_driver(ichx_gpio_driver); |
480 | |
481 | MODULE_AUTHOR("Peter Tyser <ptyser@xes-inc.com>" ); |
482 | MODULE_DESCRIPTION("GPIO interface for Intel ICH series" ); |
483 | MODULE_LICENSE("GPL" ); |
484 | MODULE_ALIAS("platform:" DRV_NAME); |
485 | |