1 // SPDX-License-Identifier: GPL-2.0-or-later
2 /*
3  * AXP20x pinctrl and GPIO driver
4  *
5  * Copyright (C) 2016 Maxime Ripard <maxime.ripard@free-electrons.com>
6  * Copyright (C) 2017 Quentin Schulz <quentin.schulz@free-electrons.com>
7  */
8 
9 #include <linux/bitops.h>
10 #include <linux/device.h>
11 #include <linux/gpio/driver.h>
12 #include <linux/init.h>
13 #include <linux/interrupt.h>
14 #include <linux/kernel.h>
15 #include <linux/mfd/axp20x.h>
16 #include <linux/module.h>
17 #include <linux/of.h>
18 #include <linux/platform_device.h>
19 #include <linux/regmap.h>
20 #include <linux/slab.h>
21 
22 #include <linux/pinctrl/consumer.h>
23 #include <linux/pinctrl/pinconf-generic.h>
24 #include <linux/pinctrl/pinctrl.h>
25 #include <linux/pinctrl/pinmux.h>
26 
27 #define AXP20X_GPIO_FUNCTIONS		0x7
28 #define AXP20X_GPIO_FUNCTION_OUT_LOW	0
29 #define AXP20X_GPIO_FUNCTION_OUT_HIGH	1
30 #define AXP20X_GPIO_FUNCTION_INPUT	2
31 
32 #define AXP20X_GPIO3_FUNCTIONS		GENMASK(2, 1)
33 #define AXP20X_GPIO3_FUNCTION_OUT_LOW	0
34 #define AXP20X_GPIO3_FUNCTION_OUT_HIGH	2
35 #define AXP20X_GPIO3_FUNCTION_INPUT	4
36 
37 #define AXP20X_FUNC_GPIO_OUT		0
38 #define AXP20X_FUNC_GPIO_IN		1
39 #define AXP20X_FUNC_LDO			2
40 #define AXP20X_FUNC_ADC			3
41 #define AXP20X_FUNCS_NB			4
42 
43 #define AXP20X_MUX_GPIO_OUT		0
44 #define AXP20X_MUX_GPIO_IN		BIT(1)
45 #define AXP20X_MUX_ADC			BIT(2)
46 
47 #define AXP813_MUX_ADC			(BIT(2) | BIT(0))
48 
49 struct axp20x_pctrl_desc {
50 	const struct pinctrl_pin_desc	*pins;
51 	unsigned int			npins;
52 	/* Stores the pins supporting LDO function. Bit offset is pin number. */
53 	u8				ldo_mask;
54 	/* Stores the pins supporting ADC function. Bit offset is pin number. */
55 	u8				adc_mask;
56 	u8				gpio_status_offset;
57 	u8				adc_mux;
58 };
59 
60 struct axp20x_pinctrl_function {
61 	const char	*name;
62 	unsigned int	muxval;
63 	const char	**groups;
64 	unsigned int	ngroups;
65 };
66 
67 struct axp20x_pctl {
68 	struct gpio_chip	chip;
69 	struct regmap		*regmap;
70 	struct pinctrl_dev			*pctl_dev;
71 	struct device				*dev;
72 	const struct axp20x_pctrl_desc		*desc;
73 	struct axp20x_pinctrl_function		funcs[AXP20X_FUNCS_NB];
74 };
75 
76 static const struct pinctrl_pin_desc axp209_pins[] = {
77 	PINCTRL_PIN(0, "GPIO0"),
78 	PINCTRL_PIN(1, "GPIO1"),
79 	PINCTRL_PIN(2, "GPIO2"),
80 	PINCTRL_PIN(3, "GPIO3"),
81 };
82 
83 static const struct pinctrl_pin_desc axp22x_pins[] = {
84 	PINCTRL_PIN(0, "GPIO0"),
85 	PINCTRL_PIN(1, "GPIO1"),
86 };
87 
88 static const struct axp20x_pctrl_desc axp20x_data = {
89 	.pins	= axp209_pins,
90 	.npins	= ARRAY_SIZE(axp209_pins),
91 	.ldo_mask = BIT(0) | BIT(1),
92 	.adc_mask = BIT(0) | BIT(1),
93 	.gpio_status_offset = 4,
94 	.adc_mux = AXP20X_MUX_ADC,
95 };
96 
97 static const struct axp20x_pctrl_desc axp22x_data = {
98 	.pins	= axp22x_pins,
99 	.npins	= ARRAY_SIZE(axp22x_pins),
100 	.ldo_mask = BIT(0) | BIT(1),
101 	.gpio_status_offset = 0,
102 };
103 
104 static const struct axp20x_pctrl_desc axp813_data = {
105 	.pins	= axp22x_pins,
106 	.npins	= ARRAY_SIZE(axp22x_pins),
107 	.ldo_mask = BIT(0) | BIT(1),
108 	.adc_mask = BIT(0),
109 	.gpio_status_offset = 0,
110 	.adc_mux = AXP813_MUX_ADC,
111 };
112 
axp20x_gpio_get_reg(unsigned int offset)113 static int axp20x_gpio_get_reg(unsigned int offset)
114 {
115 	switch (offset) {
116 	case 0:
117 		return AXP20X_GPIO0_CTRL;
118 	case 1:
119 		return AXP20X_GPIO1_CTRL;
120 	case 2:
121 		return AXP20X_GPIO2_CTRL;
122 	}
123 
124 	return -EINVAL;
125 }
126 
axp20x_gpio_input(struct gpio_chip * chip,unsigned int offset)127 static int axp20x_gpio_input(struct gpio_chip *chip, unsigned int offset)
128 {
129 	return pinctrl_gpio_direction_input(chip->base + offset);
130 }
131 
axp20x_gpio_get(struct gpio_chip * chip,unsigned int offset)132 static int axp20x_gpio_get(struct gpio_chip *chip, unsigned int offset)
133 {
134 	struct axp20x_pctl *pctl = gpiochip_get_data(chip);
135 	unsigned int val;
136 	int ret;
137 
138 	/* AXP209 has GPIO3 status sharing the settings register */
139 	if (offset == 3) {
140 		ret = regmap_read(pctl->regmap, AXP20X_GPIO3_CTRL, &val);
141 		if (ret)
142 			return ret;
143 		return !!(val & BIT(0));
144 	}
145 
146 	ret = regmap_read(pctl->regmap, AXP20X_GPIO20_SS, &val);
147 	if (ret)
148 		return ret;
149 
150 	return !!(val & BIT(offset + pctl->desc->gpio_status_offset));
151 }
152 
axp20x_gpio_get_direction(struct gpio_chip * chip,unsigned int offset)153 static int axp20x_gpio_get_direction(struct gpio_chip *chip,
154 				     unsigned int offset)
155 {
156 	struct axp20x_pctl *pctl = gpiochip_get_data(chip);
157 	unsigned int val;
158 	int reg, ret;
159 
160 	/* AXP209 GPIO3 settings have a different layout */
161 	if (offset == 3) {
162 		ret = regmap_read(pctl->regmap, AXP20X_GPIO3_CTRL, &val);
163 		if (ret)
164 			return ret;
165 		if (val & AXP20X_GPIO3_FUNCTION_INPUT)
166 			return GPIO_LINE_DIRECTION_IN;
167 
168 		return GPIO_LINE_DIRECTION_OUT;
169 	}
170 
171 	reg = axp20x_gpio_get_reg(offset);
172 	if (reg < 0)
173 		return reg;
174 
175 	ret = regmap_read(pctl->regmap, reg, &val);
176 	if (ret)
177 		return ret;
178 
179 	/*
180 	 * This shouldn't really happen if the pin is in use already,
181 	 * or if it's not in use yet, it doesn't matter since we're
182 	 * going to change the value soon anyway. Default to output.
183 	 */
184 	if ((val & AXP20X_GPIO_FUNCTIONS) > 2)
185 		return GPIO_LINE_DIRECTION_OUT;
186 
187 	/*
188 	 * The GPIO directions are the three lowest values.
189 	 * 2 is input, 0 and 1 are output
190 	 */
191 	if (val & 2)
192 		return GPIO_LINE_DIRECTION_IN;
193 
194 	return GPIO_LINE_DIRECTION_OUT;
195 }
196 
axp20x_gpio_output(struct gpio_chip * chip,unsigned int offset,int value)197 static int axp20x_gpio_output(struct gpio_chip *chip, unsigned int offset,
198 			      int value)
199 {
200 	chip->set(chip, offset, value);
201 
202 	return 0;
203 }
204 
axp20x_gpio_set(struct gpio_chip * chip,unsigned int offset,int value)205 static void axp20x_gpio_set(struct gpio_chip *chip, unsigned int offset,
206 			    int value)
207 {
208 	struct axp20x_pctl *pctl = gpiochip_get_data(chip);
209 	int reg;
210 
211 	/* AXP209 has GPIO3 status sharing the settings register */
212 	if (offset == 3) {
213 		regmap_update_bits(pctl->regmap, AXP20X_GPIO3_CTRL,
214 				   AXP20X_GPIO3_FUNCTIONS,
215 				   value ? AXP20X_GPIO3_FUNCTION_OUT_HIGH :
216 				   AXP20X_GPIO3_FUNCTION_OUT_LOW);
217 		return;
218 	}
219 
220 	reg = axp20x_gpio_get_reg(offset);
221 	if (reg < 0)
222 		return;
223 
224 	regmap_update_bits(pctl->regmap, reg,
225 			   AXP20X_GPIO_FUNCTIONS,
226 			   value ? AXP20X_GPIO_FUNCTION_OUT_HIGH :
227 			   AXP20X_GPIO_FUNCTION_OUT_LOW);
228 }
229 
axp20x_pmx_set(struct pinctrl_dev * pctldev,unsigned int offset,u8 config)230 static int axp20x_pmx_set(struct pinctrl_dev *pctldev, unsigned int offset,
231 			  u8 config)
232 {
233 	struct axp20x_pctl *pctl = pinctrl_dev_get_drvdata(pctldev);
234 	int reg;
235 
236 	/* AXP209 GPIO3 settings have a different layout */
237 	if (offset == 3) {
238 		return regmap_update_bits(pctl->regmap, AXP20X_GPIO3_CTRL,
239 				   AXP20X_GPIO3_FUNCTIONS,
240 				   config == AXP20X_MUX_GPIO_OUT ? AXP20X_GPIO3_FUNCTION_OUT_LOW :
241 				   AXP20X_GPIO3_FUNCTION_INPUT);
242 	}
243 
244 	reg = axp20x_gpio_get_reg(offset);
245 	if (reg < 0)
246 		return reg;
247 
248 	return regmap_update_bits(pctl->regmap, reg, AXP20X_GPIO_FUNCTIONS,
249 				  config);
250 }
251 
axp20x_pmx_func_cnt(struct pinctrl_dev * pctldev)252 static int axp20x_pmx_func_cnt(struct pinctrl_dev *pctldev)
253 {
254 	struct axp20x_pctl *pctl = pinctrl_dev_get_drvdata(pctldev);
255 
256 	return ARRAY_SIZE(pctl->funcs);
257 }
258 
axp20x_pmx_func_name(struct pinctrl_dev * pctldev,unsigned int selector)259 static const char *axp20x_pmx_func_name(struct pinctrl_dev *pctldev,
260 					unsigned int selector)
261 {
262 	struct axp20x_pctl *pctl = pinctrl_dev_get_drvdata(pctldev);
263 
264 	return pctl->funcs[selector].name;
265 }
266 
axp20x_pmx_func_groups(struct pinctrl_dev * pctldev,unsigned int selector,const char * const ** groups,unsigned int * num_groups)267 static int axp20x_pmx_func_groups(struct pinctrl_dev *pctldev,
268 				  unsigned int selector,
269 				  const char * const **groups,
270 				  unsigned int *num_groups)
271 {
272 	struct axp20x_pctl *pctl = pinctrl_dev_get_drvdata(pctldev);
273 
274 	*groups = pctl->funcs[selector].groups;
275 	*num_groups = pctl->funcs[selector].ngroups;
276 
277 	return 0;
278 }
279 
axp20x_pmx_set_mux(struct pinctrl_dev * pctldev,unsigned int function,unsigned int group)280 static int axp20x_pmx_set_mux(struct pinctrl_dev *pctldev,
281 			      unsigned int function, unsigned int group)
282 {
283 	struct axp20x_pctl *pctl = pinctrl_dev_get_drvdata(pctldev);
284 	unsigned int mask;
285 
286 	/* Every pin supports GPIO_OUT and GPIO_IN functions */
287 	if (function <= AXP20X_FUNC_GPIO_IN)
288 		return axp20x_pmx_set(pctldev, group,
289 				      pctl->funcs[function].muxval);
290 
291 	if (function == AXP20X_FUNC_LDO)
292 		mask = pctl->desc->ldo_mask;
293 	else
294 		mask = pctl->desc->adc_mask;
295 
296 	if (!(BIT(group) & mask))
297 		return -EINVAL;
298 
299 	/*
300 	 * We let the regulator framework handle the LDO muxing as muxing bits
301 	 * are basically also regulators on/off bits. It's better not to enforce
302 	 * any state of the regulator when selecting LDO mux so that we don't
303 	 * interfere with the regulator driver.
304 	 */
305 	if (function == AXP20X_FUNC_LDO)
306 		return 0;
307 
308 	return axp20x_pmx_set(pctldev, group, pctl->funcs[function].muxval);
309 }
310 
axp20x_pmx_gpio_set_direction(struct pinctrl_dev * pctldev,struct pinctrl_gpio_range * range,unsigned int offset,bool input)311 static int axp20x_pmx_gpio_set_direction(struct pinctrl_dev *pctldev,
312 					 struct pinctrl_gpio_range *range,
313 					 unsigned int offset, bool input)
314 {
315 	struct axp20x_pctl *pctl = pinctrl_dev_get_drvdata(pctldev);
316 
317 	if (input)
318 		return axp20x_pmx_set(pctldev, offset,
319 				      pctl->funcs[AXP20X_FUNC_GPIO_IN].muxval);
320 
321 	return axp20x_pmx_set(pctldev, offset,
322 			      pctl->funcs[AXP20X_FUNC_GPIO_OUT].muxval);
323 }
324 
325 static const struct pinmux_ops axp20x_pmx_ops = {
326 	.get_functions_count	= axp20x_pmx_func_cnt,
327 	.get_function_name	= axp20x_pmx_func_name,
328 	.get_function_groups	= axp20x_pmx_func_groups,
329 	.set_mux		= axp20x_pmx_set_mux,
330 	.gpio_set_direction	= axp20x_pmx_gpio_set_direction,
331 	.strict			= true,
332 };
333 
axp20x_groups_cnt(struct pinctrl_dev * pctldev)334 static int axp20x_groups_cnt(struct pinctrl_dev *pctldev)
335 {
336 	struct axp20x_pctl *pctl = pinctrl_dev_get_drvdata(pctldev);
337 
338 	return pctl->desc->npins;
339 }
340 
axp20x_group_pins(struct pinctrl_dev * pctldev,unsigned int selector,const unsigned int ** pins,unsigned int * num_pins)341 static int axp20x_group_pins(struct pinctrl_dev *pctldev, unsigned int selector,
342 			     const unsigned int **pins, unsigned int *num_pins)
343 {
344 	struct axp20x_pctl *pctl = pinctrl_dev_get_drvdata(pctldev);
345 
346 	*pins = (unsigned int *)&pctl->desc->pins[selector];
347 	*num_pins = 1;
348 
349 	return 0;
350 }
351 
axp20x_group_name(struct pinctrl_dev * pctldev,unsigned int selector)352 static const char *axp20x_group_name(struct pinctrl_dev *pctldev,
353 				     unsigned int selector)
354 {
355 	struct axp20x_pctl *pctl = pinctrl_dev_get_drvdata(pctldev);
356 
357 	return pctl->desc->pins[selector].name;
358 }
359 
360 static const struct pinctrl_ops axp20x_pctrl_ops = {
361 	.dt_node_to_map		= pinconf_generic_dt_node_to_map_group,
362 	.dt_free_map		= pinconf_generic_dt_free_map,
363 	.get_groups_count	= axp20x_groups_cnt,
364 	.get_group_name		= axp20x_group_name,
365 	.get_group_pins		= axp20x_group_pins,
366 };
367 
axp20x_funcs_groups_from_mask(struct device * dev,unsigned int mask,unsigned int mask_len,struct axp20x_pinctrl_function * func,const struct pinctrl_pin_desc * pins)368 static int axp20x_funcs_groups_from_mask(struct device *dev, unsigned int mask,
369 					  unsigned int mask_len,
370 					  struct axp20x_pinctrl_function *func,
371 					  const struct pinctrl_pin_desc *pins)
372 {
373 	unsigned long int mask_cpy = mask;
374 	const char **group;
375 	unsigned int ngroups = hweight8(mask);
376 	int bit;
377 
378 	func->ngroups = ngroups;
379 	if (func->ngroups > 0) {
380 		func->groups = devm_kcalloc(dev,
381 					    ngroups, sizeof(const char *),
382 					    GFP_KERNEL);
383 		if (!func->groups)
384 			return -ENOMEM;
385 		group = func->groups;
386 		for_each_set_bit(bit, &mask_cpy, mask_len) {
387 			*group = pins[bit].name;
388 			group++;
389 		}
390 	}
391 
392 	return 0;
393 }
394 
axp20x_build_funcs_groups(struct platform_device * pdev)395 static int axp20x_build_funcs_groups(struct platform_device *pdev)
396 {
397 	struct axp20x_pctl *pctl = platform_get_drvdata(pdev);
398 	int i, ret, pin, npins = pctl->desc->npins;
399 
400 	pctl->funcs[AXP20X_FUNC_GPIO_OUT].name = "gpio_out";
401 	pctl->funcs[AXP20X_FUNC_GPIO_OUT].muxval = AXP20X_MUX_GPIO_OUT;
402 	pctl->funcs[AXP20X_FUNC_GPIO_IN].name = "gpio_in";
403 	pctl->funcs[AXP20X_FUNC_GPIO_IN].muxval = AXP20X_MUX_GPIO_IN;
404 	pctl->funcs[AXP20X_FUNC_LDO].name = "ldo";
405 	/*
406 	 * Muxval for LDO is useless as we won't use it.
407 	 * See comment in axp20x_pmx_set_mux.
408 	 */
409 	pctl->funcs[AXP20X_FUNC_ADC].name = "adc";
410 	pctl->funcs[AXP20X_FUNC_ADC].muxval = pctl->desc->adc_mux;
411 
412 	/* Every pin supports GPIO_OUT and GPIO_IN functions */
413 	for (i = 0; i <= AXP20X_FUNC_GPIO_IN; i++) {
414 		pctl->funcs[i].ngroups = npins;
415 		pctl->funcs[i].groups = devm_kcalloc(&pdev->dev,
416 						     npins, sizeof(char *),
417 						     GFP_KERNEL);
418 		if (!pctl->funcs[i].groups)
419 			return -ENOMEM;
420 		for (pin = 0; pin < npins; pin++)
421 			pctl->funcs[i].groups[pin] = pctl->desc->pins[pin].name;
422 	}
423 
424 	ret = axp20x_funcs_groups_from_mask(&pdev->dev, pctl->desc->ldo_mask,
425 				      npins, &pctl->funcs[AXP20X_FUNC_LDO],
426 				      pctl->desc->pins);
427 	if (ret)
428 		return ret;
429 
430 	ret = axp20x_funcs_groups_from_mask(&pdev->dev, pctl->desc->adc_mask,
431 				      npins, &pctl->funcs[AXP20X_FUNC_ADC],
432 				      pctl->desc->pins);
433 	if (ret)
434 		return ret;
435 
436 	return 0;
437 }
438 
439 static const struct of_device_id axp20x_pctl_match[] = {
440 	{ .compatible = "x-powers,axp209-gpio", .data = &axp20x_data, },
441 	{ .compatible = "x-powers,axp221-gpio", .data = &axp22x_data, },
442 	{ .compatible = "x-powers,axp813-gpio", .data = &axp813_data, },
443 	{ }
444 };
445 MODULE_DEVICE_TABLE(of, axp20x_pctl_match);
446 
axp20x_pctl_probe(struct platform_device * pdev)447 static int axp20x_pctl_probe(struct platform_device *pdev)
448 {
449 	struct axp20x_dev *axp20x = dev_get_drvdata(pdev->dev.parent);
450 	struct axp20x_pctl *pctl;
451 	struct device *dev = &pdev->dev;
452 	struct pinctrl_desc *pctrl_desc;
453 	int ret;
454 
455 	if (!of_device_is_available(pdev->dev.of_node))
456 		return -ENODEV;
457 
458 	if (!axp20x) {
459 		dev_err(&pdev->dev, "Parent drvdata not set\n");
460 		return -EINVAL;
461 	}
462 
463 	pctl = devm_kzalloc(&pdev->dev, sizeof(*pctl), GFP_KERNEL);
464 	if (!pctl)
465 		return -ENOMEM;
466 
467 	pctl->chip.base			= -1;
468 	pctl->chip.can_sleep		= true;
469 	pctl->chip.request		= gpiochip_generic_request;
470 	pctl->chip.free			= gpiochip_generic_free;
471 	pctl->chip.parent		= &pdev->dev;
472 	pctl->chip.label		= dev_name(&pdev->dev);
473 	pctl->chip.owner		= THIS_MODULE;
474 	pctl->chip.get			= axp20x_gpio_get;
475 	pctl->chip.get_direction	= axp20x_gpio_get_direction;
476 	pctl->chip.set			= axp20x_gpio_set;
477 	pctl->chip.direction_input	= axp20x_gpio_input;
478 	pctl->chip.direction_output	= axp20x_gpio_output;
479 
480 	pctl->desc = of_device_get_match_data(dev);
481 
482 	pctl->chip.ngpio		= pctl->desc->npins;
483 
484 	pctl->regmap = axp20x->regmap;
485 	pctl->dev = &pdev->dev;
486 
487 	platform_set_drvdata(pdev, pctl);
488 
489 	ret = axp20x_build_funcs_groups(pdev);
490 	if (ret) {
491 		dev_err(&pdev->dev, "failed to build groups\n");
492 		return ret;
493 	}
494 
495 	pctrl_desc = devm_kzalloc(&pdev->dev, sizeof(*pctrl_desc), GFP_KERNEL);
496 	if (!pctrl_desc)
497 		return -ENOMEM;
498 
499 	pctrl_desc->name = dev_name(&pdev->dev);
500 	pctrl_desc->owner = THIS_MODULE;
501 	pctrl_desc->pins = pctl->desc->pins;
502 	pctrl_desc->npins = pctl->desc->npins;
503 	pctrl_desc->pctlops = &axp20x_pctrl_ops;
504 	pctrl_desc->pmxops = &axp20x_pmx_ops;
505 
506 	pctl->pctl_dev = devm_pinctrl_register(&pdev->dev, pctrl_desc, pctl);
507 	if (IS_ERR(pctl->pctl_dev)) {
508 		dev_err(&pdev->dev, "couldn't register pinctrl driver\n");
509 		return PTR_ERR(pctl->pctl_dev);
510 	}
511 
512 	ret = devm_gpiochip_add_data(&pdev->dev, &pctl->chip, pctl);
513 	if (ret) {
514 		dev_err(&pdev->dev, "Failed to register GPIO chip\n");
515 		return ret;
516 	}
517 
518 	ret = gpiochip_add_pin_range(&pctl->chip, dev_name(&pdev->dev),
519 				     pctl->desc->pins->number,
520 				     pctl->desc->pins->number,
521 				     pctl->desc->npins);
522 	if (ret) {
523 		dev_err(&pdev->dev, "failed to add pin range\n");
524 		return ret;
525 	}
526 
527 	dev_info(&pdev->dev, "AXP209 pinctrl and GPIO driver loaded\n");
528 
529 	return 0;
530 }
531 
532 static struct platform_driver axp20x_pctl_driver = {
533 	.probe		= axp20x_pctl_probe,
534 	.driver = {
535 		.name		= "axp20x-gpio",
536 		.of_match_table	= axp20x_pctl_match,
537 	},
538 };
539 
540 module_platform_driver(axp20x_pctl_driver);
541 
542 MODULE_AUTHOR("Maxime Ripard <maxime.ripard@free-electrons.com>");
543 MODULE_AUTHOR("Quentin Schulz <quentin.schulz@free-electrons.com>");
544 MODULE_DESCRIPTION("AXP20x PMIC pinctrl and GPIO driver");
545 MODULE_LICENSE("GPL");
546