xref: /linux/drivers/pinctrl/meson/pinctrl-meson.c (revision 9959d9a747fddfd9e1a37f2e3fc60cbc956aad3a)
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(struct pinctrl_dev *pcdev, unsigned int pin,
224 			     unsigned long *configs, unsigned num_configs)
225 {
226 	struct meson_pinctrl *pc = pinctrl_dev_get_drvdata(pcdev);
227 	enum pin_config_param param;
228 	int i, ret;
229 
230 	for (i = 0; i < num_configs; i++) {
231 		param = pinconf_to_config_param(configs[i]);
232 
233 		switch (param) {
234 		case PIN_CONFIG_BIAS_DISABLE:
235 			ret = meson_pinconf_disable_bias(pc, pin);
236 			if (ret)
237 				return ret;
238 			break;
239 		case PIN_CONFIG_BIAS_PULL_UP:
240 			ret = meson_pinconf_enable_bias(pc, pin, true);
241 			if (ret)
242 				return ret;
243 			break;
244 		case PIN_CONFIG_BIAS_PULL_DOWN:
245 			ret = meson_pinconf_enable_bias(pc, pin, false);
246 			if (ret)
247 				return ret;
248 			break;
249 		default:
250 			return -ENOTSUPP;
251 		}
252 	}
253 
254 	return 0;
255 }
256 
257 static int meson_pinconf_get_pull(struct meson_pinctrl *pc, unsigned int pin)
258 {
259 	struct meson_bank *bank;
260 	unsigned int reg, bit, val;
261 	int ret, conf;
262 
263 	ret = meson_get_bank(pc, pin, &bank);
264 	if (ret)
265 		return ret;
266 
267 	meson_calc_reg_and_bit(bank, pin, REG_PULLEN, &reg, &bit);
268 
269 	ret = regmap_read(pc->reg_pullen, reg, &val);
270 	if (ret)
271 		return ret;
272 
273 	if (!(val & BIT(bit))) {
274 		conf = PIN_CONFIG_BIAS_DISABLE;
275 	} else {
276 		meson_calc_reg_and_bit(bank, pin, REG_PULL, &reg, &bit);
277 
278 		ret = regmap_read(pc->reg_pull, reg, &val);
279 		if (ret)
280 			return ret;
281 
282 		if (val & BIT(bit))
283 			conf = PIN_CONFIG_BIAS_PULL_UP;
284 		else
285 			conf = PIN_CONFIG_BIAS_PULL_DOWN;
286 	}
287 
288 	return conf;
289 }
290 
291 static int meson_pinconf_get(struct pinctrl_dev *pcdev, unsigned int pin,
292 			     unsigned long *config)
293 {
294 	struct meson_pinctrl *pc = pinctrl_dev_get_drvdata(pcdev);
295 	enum pin_config_param param = pinconf_to_config_param(*config);
296 	u16 arg;
297 
298 	switch (param) {
299 	case PIN_CONFIG_BIAS_DISABLE:
300 	case PIN_CONFIG_BIAS_PULL_DOWN:
301 	case PIN_CONFIG_BIAS_PULL_UP:
302 		if (meson_pinconf_get_pull(pc, pin) == param)
303 			arg = 1;
304 		else
305 			return -EINVAL;
306 		break;
307 	default:
308 		return -ENOTSUPP;
309 	}
310 
311 	*config = pinconf_to_config_packed(param, arg);
312 	dev_dbg(pc->dev, "pinconf for pin %u is %lu\n", pin, *config);
313 
314 	return 0;
315 }
316 
317 static int meson_pinconf_group_set(struct pinctrl_dev *pcdev,
318 				   unsigned int num_group,
319 				   unsigned long *configs, unsigned num_configs)
320 {
321 	struct meson_pinctrl *pc = pinctrl_dev_get_drvdata(pcdev);
322 	struct meson_pmx_group *group = &pc->data->groups[num_group];
323 	int i;
324 
325 	dev_dbg(pc->dev, "set pinconf for group %s\n", group->name);
326 
327 	for (i = 0; i < group->num_pins; i++) {
328 		meson_pinconf_set(pcdev, group->pins[i], configs,
329 				  num_configs);
330 	}
331 
332 	return 0;
333 }
334 
335 static int meson_pinconf_group_get(struct pinctrl_dev *pcdev,
336 				   unsigned int group, unsigned long *config)
337 {
338 	return -ENOTSUPP;
339 }
340 
341 static const struct pinconf_ops meson_pinconf_ops = {
342 	.pin_config_get		= meson_pinconf_get,
343 	.pin_config_set		= meson_pinconf_set,
344 	.pin_config_group_get	= meson_pinconf_group_get,
345 	.pin_config_group_set	= meson_pinconf_group_set,
346 	.is_generic		= true,
347 };
348 
349 static int meson_gpio_direction_input(struct gpio_chip *chip, unsigned gpio)
350 {
351 	struct meson_pinctrl *pc = gpiochip_get_data(chip);
352 	unsigned int reg, bit;
353 	struct meson_bank *bank;
354 	int ret;
355 
356 	ret = meson_get_bank(pc, gpio, &bank);
357 	if (ret)
358 		return ret;
359 
360 	meson_calc_reg_and_bit(bank, gpio, REG_DIR, &reg, &bit);
361 
362 	return regmap_update_bits(pc->reg_gpio, reg, BIT(bit), BIT(bit));
363 }
364 
365 static int meson_gpio_direction_output(struct gpio_chip *chip, unsigned gpio,
366 				       int value)
367 {
368 	struct meson_pinctrl *pc = gpiochip_get_data(chip);
369 	unsigned int reg, bit;
370 	struct meson_bank *bank;
371 	int ret;
372 
373 	ret = meson_get_bank(pc, gpio, &bank);
374 	if (ret)
375 		return ret;
376 
377 	meson_calc_reg_and_bit(bank, gpio, REG_DIR, &reg, &bit);
378 	ret = regmap_update_bits(pc->reg_gpio, reg, BIT(bit), 0);
379 	if (ret)
380 		return ret;
381 
382 	meson_calc_reg_and_bit(bank, gpio, REG_OUT, &reg, &bit);
383 	return regmap_update_bits(pc->reg_gpio, reg, BIT(bit),
384 				  value ? BIT(bit) : 0);
385 }
386 
387 static void meson_gpio_set(struct gpio_chip *chip, unsigned gpio, int value)
388 {
389 	struct meson_pinctrl *pc = gpiochip_get_data(chip);
390 	unsigned int reg, bit;
391 	struct meson_bank *bank;
392 	int ret;
393 
394 	ret = meson_get_bank(pc, gpio, &bank);
395 	if (ret)
396 		return;
397 
398 	meson_calc_reg_and_bit(bank, gpio, REG_OUT, &reg, &bit);
399 	regmap_update_bits(pc->reg_gpio, reg, BIT(bit),
400 			   value ? BIT(bit) : 0);
401 }
402 
403 static int meson_gpio_get(struct gpio_chip *chip, unsigned gpio)
404 {
405 	struct meson_pinctrl *pc = gpiochip_get_data(chip);
406 	unsigned int reg, bit, val;
407 	struct meson_bank *bank;
408 	int ret;
409 
410 	ret = meson_get_bank(pc, gpio, &bank);
411 	if (ret)
412 		return ret;
413 
414 	meson_calc_reg_and_bit(bank, gpio, REG_IN, &reg, &bit);
415 	regmap_read(pc->reg_gpio, reg, &val);
416 
417 	return !!(val & BIT(bit));
418 }
419 
420 static int meson_gpiolib_register(struct meson_pinctrl *pc)
421 {
422 	int ret;
423 
424 	pc->chip.label = pc->data->name;
425 	pc->chip.parent = pc->dev;
426 	pc->chip.request = gpiochip_generic_request;
427 	pc->chip.free = gpiochip_generic_free;
428 	pc->chip.direction_input = meson_gpio_direction_input;
429 	pc->chip.direction_output = meson_gpio_direction_output;
430 	pc->chip.get = meson_gpio_get;
431 	pc->chip.set = meson_gpio_set;
432 	pc->chip.base = -1;
433 	pc->chip.ngpio = pc->data->num_pins;
434 	pc->chip.can_sleep = false;
435 	pc->chip.of_node = pc->of_node;
436 	pc->chip.of_gpio_n_cells = 2;
437 
438 	ret = gpiochip_add_data(&pc->chip, pc);
439 	if (ret) {
440 		dev_err(pc->dev, "can't add gpio chip %s\n",
441 			pc->data->name);
442 		return ret;
443 	}
444 
445 	return 0;
446 }
447 
448 static struct regmap_config meson_regmap_config = {
449 	.reg_bits = 32,
450 	.val_bits = 32,
451 	.reg_stride = 4,
452 };
453 
454 static struct regmap *meson_map_resource(struct meson_pinctrl *pc,
455 					 struct device_node *node, char *name)
456 {
457 	struct resource res;
458 	void __iomem *base;
459 	int i;
460 
461 	i = of_property_match_string(node, "reg-names", name);
462 	if (of_address_to_resource(node, i, &res))
463 		return ERR_PTR(-ENOENT);
464 
465 	base = devm_ioremap_resource(pc->dev, &res);
466 	if (IS_ERR(base))
467 		return ERR_CAST(base);
468 
469 	meson_regmap_config.max_register = resource_size(&res) - 4;
470 	meson_regmap_config.name = devm_kasprintf(pc->dev, GFP_KERNEL,
471 						  "%pOFn-%s", node,
472 						  name);
473 	if (!meson_regmap_config.name)
474 		return ERR_PTR(-ENOMEM);
475 
476 	return devm_regmap_init_mmio(pc->dev, base, &meson_regmap_config);
477 }
478 
479 static int meson_pinctrl_parse_dt(struct meson_pinctrl *pc,
480 				  struct device_node *node)
481 {
482 	struct device_node *np, *gpio_np = NULL;
483 
484 	for_each_child_of_node(node, np) {
485 		if (!of_find_property(np, "gpio-controller", NULL))
486 			continue;
487 		if (gpio_np) {
488 			dev_err(pc->dev, "multiple gpio nodes\n");
489 			return -EINVAL;
490 		}
491 		gpio_np = np;
492 	}
493 
494 	if (!gpio_np) {
495 		dev_err(pc->dev, "no gpio node found\n");
496 		return -EINVAL;
497 	}
498 
499 	pc->of_node = gpio_np;
500 
501 	pc->reg_mux = meson_map_resource(pc, gpio_np, "mux");
502 	if (IS_ERR(pc->reg_mux)) {
503 		dev_err(pc->dev, "mux registers not found\n");
504 		return PTR_ERR(pc->reg_mux);
505 	}
506 
507 	pc->reg_gpio = meson_map_resource(pc, gpio_np, "gpio");
508 	if (IS_ERR(pc->reg_gpio)) {
509 		dev_err(pc->dev, "gpio registers not found\n");
510 		return PTR_ERR(pc->reg_gpio);
511 	}
512 
513 	pc->reg_pull = meson_map_resource(pc, gpio_np, "pull");
514 	/* Use gpio region if pull one is not present */
515 	if (IS_ERR(pc->reg_pull))
516 		pc->reg_pull = pc->reg_gpio;
517 
518 	pc->reg_pullen = meson_map_resource(pc, gpio_np, "pull-enable");
519 	/* Use pull region if pull-enable one is not present */
520 	if (IS_ERR(pc->reg_pullen))
521 		pc->reg_pullen = pc->reg_pull;
522 
523 	pc->reg_ds = meson_map_resource(pc, gpio_np, "ds");
524 	if (IS_ERR(pc->reg_ds)) {
525 		dev_dbg(pc->dev, "ds registers not found - skipping\n");
526 		pc->reg_ds = NULL;
527 	}
528 
529 	return 0;
530 }
531 
532 int meson_pinctrl_probe(struct platform_device *pdev)
533 {
534 	struct device *dev = &pdev->dev;
535 	struct meson_pinctrl *pc;
536 	int ret;
537 
538 	pc = devm_kzalloc(dev, sizeof(struct meson_pinctrl), GFP_KERNEL);
539 	if (!pc)
540 		return -ENOMEM;
541 
542 	pc->dev = dev;
543 	pc->data = (struct meson_pinctrl_data *) of_device_get_match_data(dev);
544 
545 	ret = meson_pinctrl_parse_dt(pc, dev->of_node);
546 	if (ret)
547 		return ret;
548 
549 	pc->desc.name		= "pinctrl-meson";
550 	pc->desc.owner		= THIS_MODULE;
551 	pc->desc.pctlops	= &meson_pctrl_ops;
552 	pc->desc.pmxops		= pc->data->pmx_ops;
553 	pc->desc.confops	= &meson_pinconf_ops;
554 	pc->desc.pins		= pc->data->pins;
555 	pc->desc.npins		= pc->data->num_pins;
556 
557 	pc->pcdev = devm_pinctrl_register(pc->dev, &pc->desc, pc);
558 	if (IS_ERR(pc->pcdev)) {
559 		dev_err(pc->dev, "can't register pinctrl device");
560 		return PTR_ERR(pc->pcdev);
561 	}
562 
563 	return meson_gpiolib_register(pc);
564 }
565