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
ichx_write_bit(int reg,unsigned int nr,int val,int verify)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(&ichx_priv.lock, flags);
129
130 return (verify && data != tmp) ? -EPERM : 0;
131 }
132
ichx_read_bit(int reg,unsigned int nr)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(&ichx_priv.lock, flags);
149
150 return !!(data & BIT(bit));
151 }
152
ichx_gpio_check_available(struct gpio_chip * gpio,unsigned int nr)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
ichx_gpio_get_direction(struct gpio_chip * gpio,unsigned int nr)158 static int ichx_gpio_get_direction(struct gpio_chip *gpio, unsigned int nr)
159 {
160 if (ichx_read_bit(GPIO_IO_SEL, nr))
161 return GPIO_LINE_DIRECTION_IN;
162
163 return GPIO_LINE_DIRECTION_OUT;
164 }
165
ichx_gpio_direction_input(struct gpio_chip * gpio,unsigned int nr)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(GPIO_IO_SEL, nr, 1, 1);
173 }
174
ichx_gpio_direction_output(struct gpio_chip * gpio,unsigned int nr,int val)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(GPO_BLINK, nr, 0, 0);
181
182 /* Set GPIO output value. */
183 ichx_write_bit(GPIO_LVL, nr, val, 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(GPIO_IO_SEL, nr, 0, 1);
190 }
191
ichx_gpio_get(struct gpio_chip * chip,unsigned int nr)192 static int ichx_gpio_get(struct gpio_chip *chip, unsigned int nr)
193 {
194 return ichx_read_bit(GPIO_LVL, nr);
195 }
196
ich6_gpio_get(struct gpio_chip * chip,unsigned int nr)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(&ichx_priv.lock, flags);
217
218 return !!((data >> 16) & BIT(nr));
219 } else {
220 return ichx_gpio_get(chip, nr);
221 }
222 }
223
ichx_gpio_request(struct gpio_chip * chip,unsigned int nr)224 static int ichx_gpio_request(struct gpio_chip *chip, unsigned int nr)
225 {
226 if (!ichx_gpio_check_available(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(GPIO_USE_SEL, nr) ? 0 : -ENODEV;
239 }
240
ich6_gpio_request(struct gpio_chip * chip,unsigned int nr)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
ichx_gpio_set(struct gpio_chip * chip,unsigned int nr,int val)255 static void ichx_gpio_set(struct gpio_chip *chip, unsigned int nr, int val)
256 {
257 ichx_write_bit(GPIO_LVL, nr, val, 0);
258 }
259
ichx_gpiolib_setup(struct gpio_chip * chip)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
ichx_gpio_request_regions(struct device * dev,struct resource * res_base,const char * name,u8 use_gpio)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
ichx_gpio_probe(struct platform_device * pdev)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, pdev->name,
429 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(&ichx_priv.chip);
460 err = gpiochip_add_data(&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
ichx_gpio_remove(struct platform_device * pdev)472 static int ichx_gpio_remove(struct platform_device *pdev)
473 {
474 gpiochip_remove(&ichx_priv.chip);
475
476 return 0;
477 }
478
479 static struct platform_driver ichx_gpio_driver = {
480 .driver = {
481 .name = DRV_NAME,
482 },
483 .probe = ichx_gpio_probe,
484 .remove = ichx_gpio_remove,
485 };
486
487 module_platform_driver(ichx_gpio_driver);
488
489 MODULE_AUTHOR("Peter Tyser <ptyser@xes-inc.com>");
490 MODULE_DESCRIPTION("GPIO interface for Intel ICH series");
491 MODULE_LICENSE("GPL");
492 MODULE_ALIAS("platform:"DRV_NAME);
493
