xref: /linux/drivers/pinctrl/meson/pinctrl-meson.c (revision 23d19ba06b9c5614d6457f5fed349ec8f6d4dac9)
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  * For the pull and GPIO configuration every bank uses a contiguous
35  * set of bits in the register sets described above; the same register
36  * can be shared by more banks with different offsets.
37  *
38  * In addition to this there are some registers shared between all
39  * banks that control the IRQ functionality. This feature is not
40  * supported at the moment by the driver.
41  */
42 
43 #include <linux/device.h>
44 #include <linux/gpio/driver.h>
45 #include <linux/init.h>
46 #include <linux/io.h>
47 #include <linux/of.h>
48 #include <linux/of_address.h>
49 #include <linux/of_device.h>
50 #include <linux/pinctrl/pinconf-generic.h>
51 #include <linux/pinctrl/pinconf.h>
52 #include <linux/pinctrl/pinctrl.h>
53 #include <linux/pinctrl/pinmux.h>
54 #include <linux/platform_device.h>
55 #include <linux/regmap.h>
56 #include <linux/seq_file.h>
57 
58 #include "../core.h"
59 #include "../pinctrl-utils.h"
60 #include "pinctrl-meson.h"
61 
62 /**
63  * meson_get_bank() - find the bank containing a given pin
64  *
65  * @pc:		the pinctrl instance
66  * @pin:	the pin number
67  * @bank:	the found bank
68  *
69  * Return:	0 on success, a negative value on error
70  */
71 static int meson_get_bank(struct meson_pinctrl *pc, unsigned int pin,
72 			  struct meson_bank **bank)
73 {
74 	int i;
75 
76 	for (i = 0; i < pc->data->num_banks; i++) {
77 		if (pin >= pc->data->banks[i].first &&
78 		    pin <= pc->data->banks[i].last) {
79 			*bank = &pc->data->banks[i];
80 			return 0;
81 		}
82 	}
83 
84 	return -EINVAL;
85 }
86 
87 /**
88  * meson_calc_reg_and_bit() - calculate register and bit for a pin
89  *
90  * @bank:	the bank containing the pin
91  * @pin:	the pin number
92  * @reg_type:	the type of register needed (pull-enable, pull, etc...)
93  * @reg:	the computed register offset
94  * @bit:	the computed bit
95  */
96 static void meson_calc_reg_and_bit(struct meson_bank *bank, unsigned int pin,
97 				   enum meson_reg_type reg_type,
98 				   unsigned int *reg, unsigned int *bit)
99 {
100 	struct meson_reg_desc *desc = &bank->regs[reg_type];
101 
102 	*reg = desc->reg * 4;
103 	*bit = desc->bit + pin - bank->first;
104 }
105 
106 static int meson_get_groups_count(struct pinctrl_dev *pcdev)
107 {
108 	struct meson_pinctrl *pc = pinctrl_dev_get_drvdata(pcdev);
109 
110 	return pc->data->num_groups;
111 }
112 
113 static const char *meson_get_group_name(struct pinctrl_dev *pcdev,
114 					unsigned selector)
115 {
116 	struct meson_pinctrl *pc = pinctrl_dev_get_drvdata(pcdev);
117 
118 	return pc->data->groups[selector].name;
119 }
120 
121 static int meson_get_group_pins(struct pinctrl_dev *pcdev, unsigned selector,
122 				const unsigned **pins, unsigned *num_pins)
123 {
124 	struct meson_pinctrl *pc = pinctrl_dev_get_drvdata(pcdev);
125 
126 	*pins = pc->data->groups[selector].pins;
127 	*num_pins = pc->data->groups[selector].num_pins;
128 
129 	return 0;
130 }
131 
132 static void meson_pin_dbg_show(struct pinctrl_dev *pcdev, struct seq_file *s,
133 			       unsigned offset)
134 {
135 	seq_printf(s, " %s", dev_name(pcdev->dev));
136 }
137 
138 static const struct pinctrl_ops meson_pctrl_ops = {
139 	.get_groups_count	= meson_get_groups_count,
140 	.get_group_name		= meson_get_group_name,
141 	.get_group_pins		= meson_get_group_pins,
142 	.dt_node_to_map		= pinconf_generic_dt_node_to_map_all,
143 	.dt_free_map		= pinctrl_utils_free_map,
144 	.pin_dbg_show		= meson_pin_dbg_show,
145 };
146 
147 int meson_pmx_get_funcs_count(struct pinctrl_dev *pcdev)
148 {
149 	struct meson_pinctrl *pc = pinctrl_dev_get_drvdata(pcdev);
150 
151 	return pc->data->num_funcs;
152 }
153 
154 const char *meson_pmx_get_func_name(struct pinctrl_dev *pcdev,
155 				    unsigned selector)
156 {
157 	struct meson_pinctrl *pc = pinctrl_dev_get_drvdata(pcdev);
158 
159 	return pc->data->funcs[selector].name;
160 }
161 
162 int meson_pmx_get_groups(struct pinctrl_dev *pcdev, unsigned selector,
163 			 const char * const **groups,
164 			 unsigned * const num_groups)
165 {
166 	struct meson_pinctrl *pc = pinctrl_dev_get_drvdata(pcdev);
167 
168 	*groups = pc->data->funcs[selector].groups;
169 	*num_groups = pc->data->funcs[selector].num_groups;
170 
171 	return 0;
172 }
173 
174 static int meson_pinconf_set(struct pinctrl_dev *pcdev, unsigned int pin,
175 			     unsigned long *configs, unsigned num_configs)
176 {
177 	struct meson_pinctrl *pc = pinctrl_dev_get_drvdata(pcdev);
178 	struct meson_bank *bank;
179 	enum pin_config_param param;
180 	unsigned int reg, bit;
181 	int i, ret;
182 
183 	ret = meson_get_bank(pc, pin, &bank);
184 	if (ret)
185 		return ret;
186 
187 	for (i = 0; i < num_configs; i++) {
188 		param = pinconf_to_config_param(configs[i]);
189 
190 		switch (param) {
191 		case PIN_CONFIG_BIAS_DISABLE:
192 			dev_dbg(pc->dev, "pin %u: disable bias\n", pin);
193 
194 			meson_calc_reg_and_bit(bank, pin, REG_PULLEN, &reg,
195 					       &bit);
196 			ret = regmap_update_bits(pc->reg_pullen, reg,
197 						 BIT(bit), 0);
198 			if (ret)
199 				return ret;
200 			break;
201 		case PIN_CONFIG_BIAS_PULL_UP:
202 			dev_dbg(pc->dev, "pin %u: enable pull-up\n", pin);
203 
204 			meson_calc_reg_and_bit(bank, pin, REG_PULLEN,
205 					       &reg, &bit);
206 			ret = regmap_update_bits(pc->reg_pullen, reg,
207 						 BIT(bit), BIT(bit));
208 			if (ret)
209 				return ret;
210 
211 			meson_calc_reg_and_bit(bank, pin, REG_PULL, &reg, &bit);
212 			ret = regmap_update_bits(pc->reg_pull, reg,
213 						 BIT(bit), BIT(bit));
214 			if (ret)
215 				return ret;
216 			break;
217 		case PIN_CONFIG_BIAS_PULL_DOWN:
218 			dev_dbg(pc->dev, "pin %u: enable pull-down\n", pin);
219 
220 			meson_calc_reg_and_bit(bank, pin, REG_PULLEN,
221 					       &reg, &bit);
222 			ret = regmap_update_bits(pc->reg_pullen, reg,
223 						 BIT(bit), BIT(bit));
224 			if (ret)
225 				return ret;
226 
227 			meson_calc_reg_and_bit(bank, pin, REG_PULL, &reg, &bit);
228 			ret = regmap_update_bits(pc->reg_pull, reg,
229 						 BIT(bit), 0);
230 			if (ret)
231 				return ret;
232 			break;
233 		default:
234 			return -ENOTSUPP;
235 		}
236 	}
237 
238 	return 0;
239 }
240 
241 static int meson_pinconf_get_pull(struct meson_pinctrl *pc, unsigned int pin)
242 {
243 	struct meson_bank *bank;
244 	unsigned int reg, bit, val;
245 	int ret, conf;
246 
247 	ret = meson_get_bank(pc, pin, &bank);
248 	if (ret)
249 		return ret;
250 
251 	meson_calc_reg_and_bit(bank, pin, REG_PULLEN, &reg, &bit);
252 
253 	ret = regmap_read(pc->reg_pullen, reg, &val);
254 	if (ret)
255 		return ret;
256 
257 	if (!(val & BIT(bit))) {
258 		conf = PIN_CONFIG_BIAS_DISABLE;
259 	} else {
260 		meson_calc_reg_and_bit(bank, pin, REG_PULL, &reg, &bit);
261 
262 		ret = regmap_read(pc->reg_pull, reg, &val);
263 		if (ret)
264 			return ret;
265 
266 		if (val & BIT(bit))
267 			conf = PIN_CONFIG_BIAS_PULL_UP;
268 		else
269 			conf = PIN_CONFIG_BIAS_PULL_DOWN;
270 	}
271 
272 	return conf;
273 }
274 
275 static int meson_pinconf_get(struct pinctrl_dev *pcdev, unsigned int pin,
276 			     unsigned long *config)
277 {
278 	struct meson_pinctrl *pc = pinctrl_dev_get_drvdata(pcdev);
279 	enum pin_config_param param = pinconf_to_config_param(*config);
280 	u16 arg;
281 
282 	switch (param) {
283 	case PIN_CONFIG_BIAS_DISABLE:
284 	case PIN_CONFIG_BIAS_PULL_DOWN:
285 	case PIN_CONFIG_BIAS_PULL_UP:
286 		if (meson_pinconf_get_pull(pc, pin) == param)
287 			arg = 1;
288 		else
289 			return -EINVAL;
290 		break;
291 	default:
292 		return -ENOTSUPP;
293 	}
294 
295 	*config = pinconf_to_config_packed(param, arg);
296 	dev_dbg(pc->dev, "pinconf for pin %u is %lu\n", pin, *config);
297 
298 	return 0;
299 }
300 
301 static int meson_pinconf_group_set(struct pinctrl_dev *pcdev,
302 				   unsigned int num_group,
303 				   unsigned long *configs, unsigned num_configs)
304 {
305 	struct meson_pinctrl *pc = pinctrl_dev_get_drvdata(pcdev);
306 	struct meson_pmx_group *group = &pc->data->groups[num_group];
307 	int i;
308 
309 	dev_dbg(pc->dev, "set pinconf for group %s\n", group->name);
310 
311 	for (i = 0; i < group->num_pins; i++) {
312 		meson_pinconf_set(pcdev, group->pins[i], configs,
313 				  num_configs);
314 	}
315 
316 	return 0;
317 }
318 
319 static int meson_pinconf_group_get(struct pinctrl_dev *pcdev,
320 				   unsigned int group, unsigned long *config)
321 {
322 	return -ENOTSUPP;
323 }
324 
325 static const struct pinconf_ops meson_pinconf_ops = {
326 	.pin_config_get		= meson_pinconf_get,
327 	.pin_config_set		= meson_pinconf_set,
328 	.pin_config_group_get	= meson_pinconf_group_get,
329 	.pin_config_group_set	= meson_pinconf_group_set,
330 	.is_generic		= true,
331 };
332 
333 static int meson_gpio_direction_input(struct gpio_chip *chip, unsigned gpio)
334 {
335 	struct meson_pinctrl *pc = gpiochip_get_data(chip);
336 	unsigned int reg, bit;
337 	struct meson_bank *bank;
338 	int ret;
339 
340 	ret = meson_get_bank(pc, gpio, &bank);
341 	if (ret)
342 		return ret;
343 
344 	meson_calc_reg_and_bit(bank, gpio, REG_DIR, &reg, &bit);
345 
346 	return regmap_update_bits(pc->reg_gpio, reg, BIT(bit), BIT(bit));
347 }
348 
349 static int meson_gpio_direction_output(struct gpio_chip *chip, unsigned gpio,
350 				       int value)
351 {
352 	struct meson_pinctrl *pc = gpiochip_get_data(chip);
353 	unsigned int reg, bit;
354 	struct meson_bank *bank;
355 	int ret;
356 
357 	ret = meson_get_bank(pc, gpio, &bank);
358 	if (ret)
359 		return ret;
360 
361 	meson_calc_reg_and_bit(bank, gpio, REG_DIR, &reg, &bit);
362 	ret = regmap_update_bits(pc->reg_gpio, reg, BIT(bit), 0);
363 	if (ret)
364 		return ret;
365 
366 	meson_calc_reg_and_bit(bank, gpio, REG_OUT, &reg, &bit);
367 	return regmap_update_bits(pc->reg_gpio, reg, BIT(bit),
368 				  value ? BIT(bit) : 0);
369 }
370 
371 static void meson_gpio_set(struct gpio_chip *chip, unsigned gpio, int value)
372 {
373 	struct meson_pinctrl *pc = gpiochip_get_data(chip);
374 	unsigned int reg, bit;
375 	struct meson_bank *bank;
376 	int ret;
377 
378 	ret = meson_get_bank(pc, gpio, &bank);
379 	if (ret)
380 		return;
381 
382 	meson_calc_reg_and_bit(bank, gpio, REG_OUT, &reg, &bit);
383 	regmap_update_bits(pc->reg_gpio, reg, BIT(bit),
384 			   value ? BIT(bit) : 0);
385 }
386 
387 static int meson_gpio_get(struct gpio_chip *chip, unsigned gpio)
388 {
389 	struct meson_pinctrl *pc = gpiochip_get_data(chip);
390 	unsigned int reg, bit, val;
391 	struct meson_bank *bank;
392 	int ret;
393 
394 	ret = meson_get_bank(pc, gpio, &bank);
395 	if (ret)
396 		return ret;
397 
398 	meson_calc_reg_and_bit(bank, gpio, REG_IN, &reg, &bit);
399 	regmap_read(pc->reg_gpio, reg, &val);
400 
401 	return !!(val & BIT(bit));
402 }
403 
404 static int meson_gpiolib_register(struct meson_pinctrl *pc)
405 {
406 	int ret;
407 
408 	pc->chip.label = pc->data->name;
409 	pc->chip.parent = pc->dev;
410 	pc->chip.request = gpiochip_generic_request;
411 	pc->chip.free = gpiochip_generic_free;
412 	pc->chip.direction_input = meson_gpio_direction_input;
413 	pc->chip.direction_output = meson_gpio_direction_output;
414 	pc->chip.get = meson_gpio_get;
415 	pc->chip.set = meson_gpio_set;
416 	pc->chip.base = -1;
417 	pc->chip.ngpio = pc->data->num_pins;
418 	pc->chip.can_sleep = false;
419 	pc->chip.of_node = pc->of_node;
420 	pc->chip.of_gpio_n_cells = 2;
421 
422 	ret = gpiochip_add_data(&pc->chip, pc);
423 	if (ret) {
424 		dev_err(pc->dev, "can't add gpio chip %s\n",
425 			pc->data->name);
426 		return ret;
427 	}
428 
429 	return 0;
430 }
431 
432 static struct regmap_config meson_regmap_config = {
433 	.reg_bits = 32,
434 	.val_bits = 32,
435 	.reg_stride = 4,
436 };
437 
438 static struct regmap *meson_map_resource(struct meson_pinctrl *pc,
439 					 struct device_node *node, char *name)
440 {
441 	struct resource res;
442 	void __iomem *base;
443 	int i;
444 
445 	i = of_property_match_string(node, "reg-names", name);
446 	if (of_address_to_resource(node, i, &res))
447 		return ERR_PTR(-ENOENT);
448 
449 	base = devm_ioremap_resource(pc->dev, &res);
450 	if (IS_ERR(base))
451 		return ERR_CAST(base);
452 
453 	meson_regmap_config.max_register = resource_size(&res) - 4;
454 	meson_regmap_config.name = devm_kasprintf(pc->dev, GFP_KERNEL,
455 						  "%pOFn-%s", node,
456 						  name);
457 	if (!meson_regmap_config.name)
458 		return ERR_PTR(-ENOMEM);
459 
460 	return devm_regmap_init_mmio(pc->dev, base, &meson_regmap_config);
461 }
462 
463 static int meson_pinctrl_parse_dt(struct meson_pinctrl *pc,
464 				  struct device_node *node)
465 {
466 	struct device_node *np, *gpio_np = NULL;
467 
468 	for_each_child_of_node(node, np) {
469 		if (!of_find_property(np, "gpio-controller", NULL))
470 			continue;
471 		if (gpio_np) {
472 			dev_err(pc->dev, "multiple gpio nodes\n");
473 			return -EINVAL;
474 		}
475 		gpio_np = np;
476 	}
477 
478 	if (!gpio_np) {
479 		dev_err(pc->dev, "no gpio node found\n");
480 		return -EINVAL;
481 	}
482 
483 	pc->of_node = gpio_np;
484 
485 	pc->reg_mux = meson_map_resource(pc, gpio_np, "mux");
486 	if (IS_ERR(pc->reg_mux)) {
487 		dev_err(pc->dev, "mux registers not found\n");
488 		return PTR_ERR(pc->reg_mux);
489 	}
490 
491 	pc->reg_pull = meson_map_resource(pc, gpio_np, "pull");
492 	if (IS_ERR(pc->reg_pull)) {
493 		dev_err(pc->dev, "pull registers not found\n");
494 		return PTR_ERR(pc->reg_pull);
495 	}
496 
497 	pc->reg_pullen = meson_map_resource(pc, gpio_np, "pull-enable");
498 	/* Use pull region if pull-enable one is not present */
499 	if (IS_ERR(pc->reg_pullen))
500 		pc->reg_pullen = pc->reg_pull;
501 
502 	pc->reg_gpio = meson_map_resource(pc, gpio_np, "gpio");
503 	if (IS_ERR(pc->reg_gpio)) {
504 		dev_err(pc->dev, "gpio registers not found\n");
505 		return PTR_ERR(pc->reg_gpio);
506 	}
507 
508 	return 0;
509 }
510 
511 int meson_pinctrl_probe(struct platform_device *pdev)
512 {
513 	struct device *dev = &pdev->dev;
514 	struct meson_pinctrl *pc;
515 	int ret;
516 
517 	pc = devm_kzalloc(dev, sizeof(struct meson_pinctrl), GFP_KERNEL);
518 	if (!pc)
519 		return -ENOMEM;
520 
521 	pc->dev = dev;
522 	pc->data = (struct meson_pinctrl_data *) of_device_get_match_data(dev);
523 
524 	ret = meson_pinctrl_parse_dt(pc, dev->of_node);
525 	if (ret)
526 		return ret;
527 
528 	pc->desc.name		= "pinctrl-meson";
529 	pc->desc.owner		= THIS_MODULE;
530 	pc->desc.pctlops	= &meson_pctrl_ops;
531 	pc->desc.pmxops		= pc->data->pmx_ops;
532 	pc->desc.confops	= &meson_pinconf_ops;
533 	pc->desc.pins		= pc->data->pins;
534 	pc->desc.npins		= pc->data->num_pins;
535 
536 	pc->pcdev = devm_pinctrl_register(pc->dev, &pc->desc, pc);
537 	if (IS_ERR(pc->pcdev)) {
538 		dev_err(pc->dev, "can't register pinctrl device");
539 		return PTR_ERR(pc->pcdev);
540 	}
541 
542 	return meson_gpiolib_register(pc);
543 }
544