xref: /linux/drivers/pinctrl/meson/pinctrl-meson.c (revision 6ea3e3bbef3705225bb675a8c57af58420c23f81)
1 /*
2  * Pin controller and GPIO driver for Amlogic Meson SoCs
3  *
4  * Copyright (C) 2014 Beniamino Galvani <b.galvani@gmail.com>
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  * version 2 as published by the Free Software Foundation.
9  *
10  * You should have received a copy of the GNU General Public License
11  * along with this program. If not, see <http://www.gnu.org/licenses/>.
12  */
13 
14 /*
15  * The available pins are organized in banks (A,B,C,D,E,X,Y,Z,AO,
16  * BOOT,CARD for meson6, X,Y,DV,H,Z,AO,BOOT,CARD for meson8 and
17  * X,Y,DV,H,AO,BOOT,CARD,DIF for meson8b) and each bank has a
18  * variable number of pins.
19  *
20  * The AO bank is special because it belongs to the Always-On power
21  * domain which can't be powered off; the bank also uses a set of
22  * registers different from the other banks.
23  *
24  * For each pin controller there are 4 different register ranges that
25  * control the following properties of the pins:
26  *  1) pin muxing
27  *  2) pull enable/disable
28  *  3) pull up/down
29  *  4) GPIO direction, output value, input value
30  *
31  * In some cases the register ranges for pull enable and pull
32  * direction are the same and thus there are only 3 register ranges.
33  *
34  * Since Meson G12A SoC, the ao register ranges for gpio, pull enable
35  * and pull direction are the same, so there are only 2 register ranges.
36  *
37  * For the pull and GPIO configuration every bank uses a contiguous
38  * set of bits in the register sets described above; the same register
39  * can be shared by more banks with different offsets.
40  *
41  * In addition to this there are some registers shared between all
42  * banks that control the IRQ functionality. This feature is not
43  * supported at the moment by the driver.
44  */
45 
46 #include <linux/device.h>
47 #include <linux/gpio/driver.h>
48 #include <linux/init.h>
49 #include <linux/io.h>
50 #include <linux/of.h>
51 #include <linux/of_address.h>
52 #include <linux/of_device.h>
53 #include <linux/pinctrl/pinconf-generic.h>
54 #include <linux/pinctrl/pinconf.h>
55 #include <linux/pinctrl/pinctrl.h>
56 #include <linux/pinctrl/pinmux.h>
57 #include <linux/platform_device.h>
58 #include <linux/regmap.h>
59 #include <linux/seq_file.h>
60 
61 #include "../core.h"
62 #include "../pinctrl-utils.h"
63 #include "pinctrl-meson.h"
64 
65 /**
66  * meson_get_bank() - find the bank containing a given pin
67  *
68  * @pc:		the pinctrl instance
69  * @pin:	the pin number
70  * @bank:	the found bank
71  *
72  * Return:	0 on success, a negative value on error
73  */
74 static int meson_get_bank(struct meson_pinctrl *pc, unsigned int pin,
75 			  struct meson_bank **bank)
76 {
77 	int i;
78 
79 	for (i = 0; i < pc->data->num_banks; i++) {
80 		if (pin >= pc->data->banks[i].first &&
81 		    pin <= pc->data->banks[i].last) {
82 			*bank = &pc->data->banks[i];
83 			return 0;
84 		}
85 	}
86 
87 	return -EINVAL;
88 }
89 
90 /**
91  * meson_calc_reg_and_bit() - calculate register and bit for a pin
92  *
93  * @bank:	the bank containing the pin
94  * @pin:	the pin number
95  * @reg_type:	the type of register needed (pull-enable, pull, etc...)
96  * @reg:	the computed register offset
97  * @bit:	the computed bit
98  */
99 static void meson_calc_reg_and_bit(struct meson_bank *bank, unsigned int pin,
100 				   enum meson_reg_type reg_type,
101 				   unsigned int *reg, unsigned int *bit)
102 {
103 	struct meson_reg_desc *desc = &bank->regs[reg_type];
104 
105 	*reg = desc->reg * 4;
106 	*bit = desc->bit + pin - bank->first;
107 }
108 
109 static int meson_get_groups_count(struct pinctrl_dev *pcdev)
110 {
111 	struct meson_pinctrl *pc = pinctrl_dev_get_drvdata(pcdev);
112 
113 	return pc->data->num_groups;
114 }
115 
116 static const char *meson_get_group_name(struct pinctrl_dev *pcdev,
117 					unsigned selector)
118 {
119 	struct meson_pinctrl *pc = pinctrl_dev_get_drvdata(pcdev);
120 
121 	return pc->data->groups[selector].name;
122 }
123 
124 static int meson_get_group_pins(struct pinctrl_dev *pcdev, unsigned selector,
125 				const unsigned **pins, unsigned *num_pins)
126 {
127 	struct meson_pinctrl *pc = pinctrl_dev_get_drvdata(pcdev);
128 
129 	*pins = pc->data->groups[selector].pins;
130 	*num_pins = pc->data->groups[selector].num_pins;
131 
132 	return 0;
133 }
134 
135 static void meson_pin_dbg_show(struct pinctrl_dev *pcdev, struct seq_file *s,
136 			       unsigned offset)
137 {
138 	seq_printf(s, " %s", dev_name(pcdev->dev));
139 }
140 
141 static const struct pinctrl_ops meson_pctrl_ops = {
142 	.get_groups_count	= meson_get_groups_count,
143 	.get_group_name		= meson_get_group_name,
144 	.get_group_pins		= meson_get_group_pins,
145 	.dt_node_to_map		= pinconf_generic_dt_node_to_map_all,
146 	.dt_free_map		= pinctrl_utils_free_map,
147 	.pin_dbg_show		= meson_pin_dbg_show,
148 };
149 
150 int meson_pmx_get_funcs_count(struct pinctrl_dev *pcdev)
151 {
152 	struct meson_pinctrl *pc = pinctrl_dev_get_drvdata(pcdev);
153 
154 	return pc->data->num_funcs;
155 }
156 
157 const char *meson_pmx_get_func_name(struct pinctrl_dev *pcdev,
158 				    unsigned selector)
159 {
160 	struct meson_pinctrl *pc = pinctrl_dev_get_drvdata(pcdev);
161 
162 	return pc->data->funcs[selector].name;
163 }
164 
165 int meson_pmx_get_groups(struct pinctrl_dev *pcdev, unsigned selector,
166 			 const char * const **groups,
167 			 unsigned * const num_groups)
168 {
169 	struct meson_pinctrl *pc = pinctrl_dev_get_drvdata(pcdev);
170 
171 	*groups = pc->data->funcs[selector].groups;
172 	*num_groups = pc->data->funcs[selector].num_groups;
173 
174 	return 0;
175 }
176 
177 static int meson_pinconf_disable_bias(struct meson_pinctrl *pc,
178 				      unsigned int pin)
179 {
180 	struct meson_bank *bank;
181 	unsigned int reg, bit = 0;
182 	int ret;
183 
184 	ret = meson_get_bank(pc, pin, &bank);
185 	if (ret)
186 		return ret;
187 
188 	meson_calc_reg_and_bit(bank, pin, REG_PULLEN, &reg, &bit);
189 	ret = regmap_update_bits(pc->reg_pullen, reg, BIT(bit), 0);
190 	if (ret)
191 		return ret;
192 
193 	return 0;
194 }
195 
196 static int meson_pinconf_enable_bias(struct meson_pinctrl *pc, unsigned int pin,
197 				     bool pull_up)
198 {
199 	struct meson_bank *bank;
200 	unsigned int reg, bit, val = 0;
201 	int ret;
202 
203 	ret = meson_get_bank(pc, pin, &bank);
204 	if (ret)
205 		return ret;
206 
207 	meson_calc_reg_and_bit(bank, pin, REG_PULL, &reg, &bit);
208 	if (pull_up)
209 		val = BIT(bit);
210 
211 	ret = regmap_update_bits(pc->reg_pull, reg, BIT(bit), val);
212 	if (ret)
213 		return ret;
214 
215 	meson_calc_reg_and_bit(bank, pin, REG_PULLEN, &reg, &bit);
216 	ret = regmap_update_bits(pc->reg_pullen, reg, BIT(bit),	BIT(bit));
217 	if (ret)
218 		return ret;
219 
220 	return 0;
221 }
222 
223 static int meson_pinconf_set_drive_strength(struct meson_pinctrl *pc,
224 					    unsigned int pin,
225 					    u16 drive_strength_ua)
226 {
227 	struct meson_bank *bank;
228 	unsigned int reg, bit, ds_val;
229 	int ret;
230 
231 	if (!pc->reg_ds) {
232 		dev_err(pc->dev, "drive-strength not supported\n");
233 		return -ENOTSUPP;
234 	}
235 
236 	ret = meson_get_bank(pc, pin, &bank);
237 	if (ret)
238 		return ret;
239 
240 	meson_calc_reg_and_bit(bank, pin, REG_DS, &reg, &bit);
241 	bit = bit << 1;
242 
243 	if (drive_strength_ua <= 500) {
244 		ds_val = MESON_PINCONF_DRV_500UA;
245 	} else if (drive_strength_ua <= 2500) {
246 		ds_val = MESON_PINCONF_DRV_2500UA;
247 	} else if (drive_strength_ua <= 3000) {
248 		ds_val = MESON_PINCONF_DRV_3000UA;
249 	} else if (drive_strength_ua <= 4000) {
250 		ds_val = MESON_PINCONF_DRV_4000UA;
251 	} else {
252 		dev_warn_once(pc->dev,
253 			      "pin %u: invalid drive-strength : %d , default to 4mA\n",
254 			      pin, drive_strength_ua);
255 		ds_val = MESON_PINCONF_DRV_4000UA;
256 	}
257 
258 	ret = regmap_update_bits(pc->reg_ds, reg, 0x3 << bit, ds_val << bit);
259 	if (ret)
260 		return ret;
261 
262 	return 0;
263 }
264 
265 static int meson_pinconf_set(struct pinctrl_dev *pcdev, unsigned int pin,
266 			     unsigned long *configs, unsigned num_configs)
267 {
268 	struct meson_pinctrl *pc = pinctrl_dev_get_drvdata(pcdev);
269 	enum pin_config_param param;
270 	unsigned int drive_strength_ua;
271 	int i, ret;
272 
273 	for (i = 0; i < num_configs; i++) {
274 		param = pinconf_to_config_param(configs[i]);
275 
276 		switch (param) {
277 		case PIN_CONFIG_BIAS_DISABLE:
278 			ret = meson_pinconf_disable_bias(pc, pin);
279 			if (ret)
280 				return ret;
281 			break;
282 		case PIN_CONFIG_BIAS_PULL_UP:
283 			ret = meson_pinconf_enable_bias(pc, pin, true);
284 			if (ret)
285 				return ret;
286 			break;
287 		case PIN_CONFIG_BIAS_PULL_DOWN:
288 			ret = meson_pinconf_enable_bias(pc, pin, false);
289 			if (ret)
290 				return ret;
291 			break;
292 		case PIN_CONFIG_DRIVE_STRENGTH_UA:
293 			drive_strength_ua =
294 				pinconf_to_config_argument(configs[i]);
295 			ret = meson_pinconf_set_drive_strength
296 				(pc, pin, drive_strength_ua);
297 			if (ret)
298 				return ret;
299 			break;
300 		default:
301 			return -ENOTSUPP;
302 		}
303 	}
304 
305 	return 0;
306 }
307 
308 static int meson_pinconf_get_pull(struct meson_pinctrl *pc, unsigned int pin)
309 {
310 	struct meson_bank *bank;
311 	unsigned int reg, bit, val;
312 	int ret, conf;
313 
314 	ret = meson_get_bank(pc, pin, &bank);
315 	if (ret)
316 		return ret;
317 
318 	meson_calc_reg_and_bit(bank, pin, REG_PULLEN, &reg, &bit);
319 
320 	ret = regmap_read(pc->reg_pullen, reg, &val);
321 	if (ret)
322 		return ret;
323 
324 	if (!(val & BIT(bit))) {
325 		conf = PIN_CONFIG_BIAS_DISABLE;
326 	} else {
327 		meson_calc_reg_and_bit(bank, pin, REG_PULL, &reg, &bit);
328 
329 		ret = regmap_read(pc->reg_pull, reg, &val);
330 		if (ret)
331 			return ret;
332 
333 		if (val & BIT(bit))
334 			conf = PIN_CONFIG_BIAS_PULL_UP;
335 		else
336 			conf = PIN_CONFIG_BIAS_PULL_DOWN;
337 	}
338 
339 	return conf;
340 }
341 
342 static int meson_pinconf_get_drive_strength(struct meson_pinctrl *pc,
343 					    unsigned int pin,
344 					    u16 *drive_strength_ua)
345 {
346 	struct meson_bank *bank;
347 	unsigned int reg, bit;
348 	unsigned int val;
349 	int ret;
350 
351 	if (!pc->reg_ds)
352 		return -ENOTSUPP;
353 
354 	ret = meson_get_bank(pc, pin, &bank);
355 	if (ret)
356 		return ret;
357 
358 	meson_calc_reg_and_bit(bank, pin, REG_DS, &reg, &bit);
359 
360 	ret = regmap_read(pc->reg_ds, reg, &val);
361 	if (ret)
362 		return ret;
363 
364 	switch ((val >> bit) & 0x3) {
365 	case MESON_PINCONF_DRV_500UA:
366 		*drive_strength_ua = 500;
367 		break;
368 	case MESON_PINCONF_DRV_2500UA:
369 		*drive_strength_ua = 2500;
370 		break;
371 	case MESON_PINCONF_DRV_3000UA:
372 		*drive_strength_ua = 3000;
373 		break;
374 	case MESON_PINCONF_DRV_4000UA:
375 		*drive_strength_ua = 4000;
376 		break;
377 	default:
378 		return -EINVAL;
379 	}
380 
381 	return 0;
382 }
383 
384 static int meson_pinconf_get(struct pinctrl_dev *pcdev, unsigned int pin,
385 			     unsigned long *config)
386 {
387 	struct meson_pinctrl *pc = pinctrl_dev_get_drvdata(pcdev);
388 	enum pin_config_param param = pinconf_to_config_param(*config);
389 	u16 arg;
390 	int ret;
391 
392 	switch (param) {
393 	case PIN_CONFIG_BIAS_DISABLE:
394 	case PIN_CONFIG_BIAS_PULL_DOWN:
395 	case PIN_CONFIG_BIAS_PULL_UP:
396 		if (meson_pinconf_get_pull(pc, pin) == param)
397 			arg = 1;
398 		else
399 			return -EINVAL;
400 		break;
401 	case PIN_CONFIG_DRIVE_STRENGTH_UA:
402 		ret = meson_pinconf_get_drive_strength(pc, pin, &arg);
403 		if (ret)
404 			return ret;
405 		break;
406 	default:
407 		return -ENOTSUPP;
408 	}
409 
410 	*config = pinconf_to_config_packed(param, arg);
411 	dev_dbg(pc->dev, "pinconf for pin %u is %lu\n", pin, *config);
412 
413 	return 0;
414 }
415 
416 static int meson_pinconf_group_set(struct pinctrl_dev *pcdev,
417 				   unsigned int num_group,
418 				   unsigned long *configs, unsigned num_configs)
419 {
420 	struct meson_pinctrl *pc = pinctrl_dev_get_drvdata(pcdev);
421 	struct meson_pmx_group *group = &pc->data->groups[num_group];
422 	int i;
423 
424 	dev_dbg(pc->dev, "set pinconf for group %s\n", group->name);
425 
426 	for (i = 0; i < group->num_pins; i++) {
427 		meson_pinconf_set(pcdev, group->pins[i], configs,
428 				  num_configs);
429 	}
430 
431 	return 0;
432 }
433 
434 static int meson_pinconf_group_get(struct pinctrl_dev *pcdev,
435 				   unsigned int group, unsigned long *config)
436 {
437 	return -ENOTSUPP;
438 }
439 
440 static const struct pinconf_ops meson_pinconf_ops = {
441 	.pin_config_get		= meson_pinconf_get,
442 	.pin_config_set		= meson_pinconf_set,
443 	.pin_config_group_get	= meson_pinconf_group_get,
444 	.pin_config_group_set	= meson_pinconf_group_set,
445 	.is_generic		= true,
446 };
447 
448 static int meson_gpio_direction_input(struct gpio_chip *chip, unsigned gpio)
449 {
450 	struct meson_pinctrl *pc = gpiochip_get_data(chip);
451 	unsigned int reg, bit;
452 	struct meson_bank *bank;
453 	int ret;
454 
455 	ret = meson_get_bank(pc, gpio, &bank);
456 	if (ret)
457 		return ret;
458 
459 	meson_calc_reg_and_bit(bank, gpio, REG_DIR, &reg, &bit);
460 
461 	return regmap_update_bits(pc->reg_gpio, reg, BIT(bit), BIT(bit));
462 }
463 
464 static int meson_gpio_direction_output(struct gpio_chip *chip, unsigned gpio,
465 				       int value)
466 {
467 	struct meson_pinctrl *pc = gpiochip_get_data(chip);
468 	unsigned int reg, bit;
469 	struct meson_bank *bank;
470 	int ret;
471 
472 	ret = meson_get_bank(pc, gpio, &bank);
473 	if (ret)
474 		return ret;
475 
476 	meson_calc_reg_and_bit(bank, gpio, REG_DIR, &reg, &bit);
477 	ret = regmap_update_bits(pc->reg_gpio, reg, BIT(bit), 0);
478 	if (ret)
479 		return ret;
480 
481 	meson_calc_reg_and_bit(bank, gpio, REG_OUT, &reg, &bit);
482 	return regmap_update_bits(pc->reg_gpio, reg, BIT(bit),
483 				  value ? BIT(bit) : 0);
484 }
485 
486 static void meson_gpio_set(struct gpio_chip *chip, unsigned gpio, int value)
487 {
488 	struct meson_pinctrl *pc = gpiochip_get_data(chip);
489 	unsigned int reg, bit;
490 	struct meson_bank *bank;
491 	int ret;
492 
493 	ret = meson_get_bank(pc, gpio, &bank);
494 	if (ret)
495 		return;
496 
497 	meson_calc_reg_and_bit(bank, gpio, REG_OUT, &reg, &bit);
498 	regmap_update_bits(pc->reg_gpio, reg, BIT(bit),
499 			   value ? BIT(bit) : 0);
500 }
501 
502 static int meson_gpio_get(struct gpio_chip *chip, unsigned gpio)
503 {
504 	struct meson_pinctrl *pc = gpiochip_get_data(chip);
505 	unsigned int reg, bit, val;
506 	struct meson_bank *bank;
507 	int ret;
508 
509 	ret = meson_get_bank(pc, gpio, &bank);
510 	if (ret)
511 		return ret;
512 
513 	meson_calc_reg_and_bit(bank, gpio, REG_IN, &reg, &bit);
514 	regmap_read(pc->reg_gpio, reg, &val);
515 
516 	return !!(val & BIT(bit));
517 }
518 
519 static int meson_gpiolib_register(struct meson_pinctrl *pc)
520 {
521 	int ret;
522 
523 	pc->chip.label = pc->data->name;
524 	pc->chip.parent = pc->dev;
525 	pc->chip.request = gpiochip_generic_request;
526 	pc->chip.free = gpiochip_generic_free;
527 	pc->chip.direction_input = meson_gpio_direction_input;
528 	pc->chip.direction_output = meson_gpio_direction_output;
529 	pc->chip.get = meson_gpio_get;
530 	pc->chip.set = meson_gpio_set;
531 	pc->chip.base = -1;
532 	pc->chip.ngpio = pc->data->num_pins;
533 	pc->chip.can_sleep = false;
534 	pc->chip.of_node = pc->of_node;
535 	pc->chip.of_gpio_n_cells = 2;
536 
537 	ret = gpiochip_add_data(&pc->chip, pc);
538 	if (ret) {
539 		dev_err(pc->dev, "can't add gpio chip %s\n",
540 			pc->data->name);
541 		return ret;
542 	}
543 
544 	return 0;
545 }
546 
547 static struct regmap_config meson_regmap_config = {
548 	.reg_bits = 32,
549 	.val_bits = 32,
550 	.reg_stride = 4,
551 };
552 
553 static struct regmap *meson_map_resource(struct meson_pinctrl *pc,
554 					 struct device_node *node, char *name)
555 {
556 	struct resource res;
557 	void __iomem *base;
558 	int i;
559 
560 	i = of_property_match_string(node, "reg-names", name);
561 	if (of_address_to_resource(node, i, &res))
562 		return ERR_PTR(-ENOENT);
563 
564 	base = devm_ioremap_resource(pc->dev, &res);
565 	if (IS_ERR(base))
566 		return ERR_CAST(base);
567 
568 	meson_regmap_config.max_register = resource_size(&res) - 4;
569 	meson_regmap_config.name = devm_kasprintf(pc->dev, GFP_KERNEL,
570 						  "%pOFn-%s", node,
571 						  name);
572 	if (!meson_regmap_config.name)
573 		return ERR_PTR(-ENOMEM);
574 
575 	return devm_regmap_init_mmio(pc->dev, base, &meson_regmap_config);
576 }
577 
578 static int meson_pinctrl_parse_dt(struct meson_pinctrl *pc,
579 				  struct device_node *node)
580 {
581 	struct device_node *np, *gpio_np = NULL;
582 
583 	for_each_child_of_node(node, np) {
584 		if (!of_find_property(np, "gpio-controller", NULL))
585 			continue;
586 		if (gpio_np) {
587 			dev_err(pc->dev, "multiple gpio nodes\n");
588 			return -EINVAL;
589 		}
590 		gpio_np = np;
591 	}
592 
593 	if (!gpio_np) {
594 		dev_err(pc->dev, "no gpio node found\n");
595 		return -EINVAL;
596 	}
597 
598 	pc->of_node = gpio_np;
599 
600 	pc->reg_mux = meson_map_resource(pc, gpio_np, "mux");
601 	if (IS_ERR(pc->reg_mux)) {
602 		dev_err(pc->dev, "mux registers not found\n");
603 		return PTR_ERR(pc->reg_mux);
604 	}
605 
606 	pc->reg_gpio = meson_map_resource(pc, gpio_np, "gpio");
607 	if (IS_ERR(pc->reg_gpio)) {
608 		dev_err(pc->dev, "gpio registers not found\n");
609 		return PTR_ERR(pc->reg_gpio);
610 	}
611 
612 	pc->reg_pull = meson_map_resource(pc, gpio_np, "pull");
613 	/* Use gpio region if pull one is not present */
614 	if (IS_ERR(pc->reg_pull))
615 		pc->reg_pull = pc->reg_gpio;
616 
617 	pc->reg_pullen = meson_map_resource(pc, gpio_np, "pull-enable");
618 	/* Use pull region if pull-enable one is not present */
619 	if (IS_ERR(pc->reg_pullen))
620 		pc->reg_pullen = pc->reg_pull;
621 
622 	pc->reg_ds = meson_map_resource(pc, gpio_np, "ds");
623 	if (IS_ERR(pc->reg_ds)) {
624 		dev_dbg(pc->dev, "ds registers not found - skipping\n");
625 		pc->reg_ds = NULL;
626 	}
627 
628 	return 0;
629 }
630 
631 int meson_pinctrl_probe(struct platform_device *pdev)
632 {
633 	struct device *dev = &pdev->dev;
634 	struct meson_pinctrl *pc;
635 	int ret;
636 
637 	pc = devm_kzalloc(dev, sizeof(struct meson_pinctrl), GFP_KERNEL);
638 	if (!pc)
639 		return -ENOMEM;
640 
641 	pc->dev = dev;
642 	pc->data = (struct meson_pinctrl_data *) of_device_get_match_data(dev);
643 
644 	ret = meson_pinctrl_parse_dt(pc, dev->of_node);
645 	if (ret)
646 		return ret;
647 
648 	pc->desc.name		= "pinctrl-meson";
649 	pc->desc.owner		= THIS_MODULE;
650 	pc->desc.pctlops	= &meson_pctrl_ops;
651 	pc->desc.pmxops		= pc->data->pmx_ops;
652 	pc->desc.confops	= &meson_pinconf_ops;
653 	pc->desc.pins		= pc->data->pins;
654 	pc->desc.npins		= pc->data->num_pins;
655 
656 	pc->pcdev = devm_pinctrl_register(pc->dev, &pc->desc, pc);
657 	if (IS_ERR(pc->pcdev)) {
658 		dev_err(pc->dev, "can't register pinctrl device");
659 		return PTR_ERR(pc->pcdev);
660 	}
661 
662 	return meson_gpiolib_register(pc);
663 }
664