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/of_device.h>
19 #include <linux/platform_device.h>
20 #include <linux/regmap.h>
21 #include <linux/slab.h>
22 
23 #include <linux/pinctrl/consumer.h>
24 #include <linux/pinctrl/pinconf-generic.h>
25 #include <linux/pinctrl/pinctrl.h>
26 #include <linux/pinctrl/pinmux.h>
27 
28 #define AXP20X_GPIO_FUNCTIONS		0x7
29 #define AXP20X_GPIO_FUNCTION_OUT_LOW	0
30 #define AXP20X_GPIO_FUNCTION_OUT_HIGH	1
31 #define AXP20X_GPIO_FUNCTION_INPUT	2
32 
33 #define AXP20X_GPIO3_FUNCTIONS		GENMASK(2, 1)
34 #define AXP20X_GPIO3_FUNCTION_OUT_LOW	0
35 #define AXP20X_GPIO3_FUNCTION_OUT_HIGH	2
36 #define AXP20X_GPIO3_FUNCTION_INPUT	4
37 
38 #define AXP20X_FUNC_GPIO_OUT		0
39 #define AXP20X_FUNC_GPIO_IN		1
40 #define AXP20X_FUNC_LDO			2
41 #define AXP20X_FUNC_ADC			3
42 #define AXP20X_FUNCS_NB			4
43 
44 #define AXP20X_MUX_GPIO_OUT		0
45 #define AXP20X_MUX_GPIO_IN		BIT(1)
46 #define AXP20X_MUX_ADC			BIT(2)
47 
48 #define AXP813_MUX_ADC			(BIT(2) | BIT(0))
49 
50 struct axp20x_pctrl_desc {
51 	const struct pinctrl_pin_desc	*pins;
52 	unsigned int			npins;
53 	/* Stores the pins supporting LDO function. Bit offset is pin number. */
54 	u8				ldo_mask;
55 	/* Stores the pins supporting ADC function. Bit offset is pin number. */
56 	u8				adc_mask;
57 	u8				gpio_status_offset;
58 	u8				adc_mux;
59 };
60 
61 struct axp20x_pinctrl_function {
62 	const char	*name;
63 	unsigned int	muxval;
64 	const char	**groups;
65 	unsigned int	ngroups;
66 };
67 
68 struct axp20x_pctl {
69 	struct gpio_chip	chip;
70 	struct regmap		*regmap;
71 	struct pinctrl_dev			*pctl_dev;
72 	struct device				*dev;
73 	const struct axp20x_pctrl_desc		*desc;
74 	struct axp20x_pinctrl_function		funcs[AXP20X_FUNCS_NB];
75 };
76 
77 static const struct pinctrl_pin_desc axp209_pins[] = {
78 	PINCTRL_PIN(0, "GPIO0"),
79 	PINCTRL_PIN(1, "GPIO1"),
80 	PINCTRL_PIN(2, "GPIO2"),
81 	PINCTRL_PIN(3, "GPIO3"),
82 };
83 
84 static const struct pinctrl_pin_desc axp22x_pins[] = {
85 	PINCTRL_PIN(0, "GPIO0"),
86 	PINCTRL_PIN(1, "GPIO1"),
87 };
88 
89 static const struct axp20x_pctrl_desc axp20x_data = {
90 	.pins	= axp209_pins,
91 	.npins	= ARRAY_SIZE(axp209_pins),
92 	.ldo_mask = BIT(0) | BIT(1),
93 	.adc_mask = BIT(0) | BIT(1),
94 	.gpio_status_offset = 4,
95 	.adc_mux = AXP20X_MUX_ADC,
96 };
97 
98 static const struct axp20x_pctrl_desc axp22x_data = {
99 	.pins	= axp22x_pins,
100 	.npins	= ARRAY_SIZE(axp22x_pins),
101 	.ldo_mask = BIT(0) | BIT(1),
102 	.gpio_status_offset = 0,
103 };
104 
105 static const struct axp20x_pctrl_desc axp813_data = {
106 	.pins	= axp22x_pins,
107 	.npins	= ARRAY_SIZE(axp22x_pins),
108 	.ldo_mask = BIT(0) | BIT(1),
109 	.adc_mask = BIT(0),
110 	.gpio_status_offset = 0,
111 	.adc_mux = AXP813_MUX_ADC,
112 };
113 
114 static int axp20x_gpio_get_reg(unsigned int offset)
115 {
116 	switch (offset) {
117 	case 0:
118 		return AXP20X_GPIO0_CTRL;
119 	case 1:
120 		return AXP20X_GPIO1_CTRL;
121 	case 2:
122 		return AXP20X_GPIO2_CTRL;
123 	}
124 
125 	return -EINVAL;
126 }
127 
128 static int axp20x_gpio_input(struct gpio_chip *chip, unsigned int offset)
129 {
130 	return pinctrl_gpio_direction_input(chip->base + offset);
131 }
132 
133 static int axp20x_gpio_get(struct gpio_chip *chip, unsigned int offset)
134 {
135 	struct axp20x_pctl *pctl = gpiochip_get_data(chip);
136 	unsigned int val;
137 	int ret;
138 
139 	/* AXP209 has GPIO3 status sharing the settings register */
140 	if (offset == 3) {
141 		ret = regmap_read(pctl->regmap, AXP20X_GPIO3_CTRL, &val);
142 		if (ret)
143 			return ret;
144 		return !!(val & BIT(0));
145 	}
146 
147 	ret = regmap_read(pctl->regmap, AXP20X_GPIO20_SS, &val);
148 	if (ret)
149 		return ret;
150 
151 	return !!(val & BIT(offset + pctl->desc->gpio_status_offset));
152 }
153 
154 static int axp20x_gpio_get_direction(struct gpio_chip *chip,
155 				     unsigned int offset)
156 {
157 	struct axp20x_pctl *pctl = gpiochip_get_data(chip);
158 	unsigned int val;
159 	int reg, ret;
160 
161 	/* AXP209 GPIO3 settings have a different layout */
162 	if (offset == 3) {
163 		ret = regmap_read(pctl->regmap, AXP20X_GPIO3_CTRL, &val);
164 		if (ret)
165 			return ret;
166 		if (val & AXP20X_GPIO3_FUNCTION_INPUT)
167 			return GPIO_LINE_DIRECTION_IN;
168 
169 		return GPIO_LINE_DIRECTION_OUT;
170 	}
171 
172 	reg = axp20x_gpio_get_reg(offset);
173 	if (reg < 0)
174 		return reg;
175 
176 	ret = regmap_read(pctl->regmap, reg, &val);
177 	if (ret)
178 		return ret;
179 
180 	/*
181 	 * This shouldn't really happen if the pin is in use already,
182 	 * or if it's not in use yet, it doesn't matter since we're
183 	 * going to change the value soon anyway. Default to output.
184 	 */
185 	if ((val & AXP20X_GPIO_FUNCTIONS) > 2)
186 		return GPIO_LINE_DIRECTION_OUT;
187 
188 	/*
189 	 * The GPIO directions are the three lowest values.
190 	 * 2 is input, 0 and 1 are output
191 	 */
192 	if (val & 2)
193 		return GPIO_LINE_DIRECTION_IN;
194 
195 	return GPIO_LINE_DIRECTION_OUT;
196 }
197 
198 static int axp20x_gpio_output(struct gpio_chip *chip, unsigned int offset,
199 			      int value)
200 {
201 	chip->set(chip, offset, value);
202 
203 	return 0;
204 }
205 
206 static void axp20x_gpio_set(struct gpio_chip *chip, unsigned int offset,
207 			    int value)
208 {
209 	struct axp20x_pctl *pctl = gpiochip_get_data(chip);
210 	int reg;
211 
212 	/* AXP209 has GPIO3 status sharing the settings register */
213 	if (offset == 3) {
214 		regmap_update_bits(pctl->regmap, AXP20X_GPIO3_CTRL,
215 				   AXP20X_GPIO3_FUNCTIONS,
216 				   value ? AXP20X_GPIO3_FUNCTION_OUT_HIGH :
217 				   AXP20X_GPIO3_FUNCTION_OUT_LOW);
218 		return;
219 	}
220 
221 	reg = axp20x_gpio_get_reg(offset);
222 	if (reg < 0)
223 		return;
224 
225 	regmap_update_bits(pctl->regmap, reg,
226 			   AXP20X_GPIO_FUNCTIONS,
227 			   value ? AXP20X_GPIO_FUNCTION_OUT_HIGH :
228 			   AXP20X_GPIO_FUNCTION_OUT_LOW);
229 }
230 
231 static int axp20x_pmx_set(struct pinctrl_dev *pctldev, unsigned int offset,
232 			  u8 config)
233 {
234 	struct axp20x_pctl *pctl = pinctrl_dev_get_drvdata(pctldev);
235 	int reg;
236 
237 	/* AXP209 GPIO3 settings have a different layout */
238 	if (offset == 3) {
239 		return regmap_update_bits(pctl->regmap, AXP20X_GPIO3_CTRL,
240 				   AXP20X_GPIO3_FUNCTIONS,
241 				   config == AXP20X_MUX_GPIO_OUT ? AXP20X_GPIO3_FUNCTION_OUT_LOW :
242 				   AXP20X_GPIO3_FUNCTION_INPUT);
243 	}
244 
245 	reg = axp20x_gpio_get_reg(offset);
246 	if (reg < 0)
247 		return reg;
248 
249 	return regmap_update_bits(pctl->regmap, reg, AXP20X_GPIO_FUNCTIONS,
250 				  config);
251 }
252 
253 static int axp20x_pmx_func_cnt(struct pinctrl_dev *pctldev)
254 {
255 	struct axp20x_pctl *pctl = pinctrl_dev_get_drvdata(pctldev);
256 
257 	return ARRAY_SIZE(pctl->funcs);
258 }
259 
260 static const char *axp20x_pmx_func_name(struct pinctrl_dev *pctldev,
261 					unsigned int selector)
262 {
263 	struct axp20x_pctl *pctl = pinctrl_dev_get_drvdata(pctldev);
264 
265 	return pctl->funcs[selector].name;
266 }
267 
268 static int axp20x_pmx_func_groups(struct pinctrl_dev *pctldev,
269 				  unsigned int selector,
270 				  const char * const **groups,
271 				  unsigned int *num_groups)
272 {
273 	struct axp20x_pctl *pctl = pinctrl_dev_get_drvdata(pctldev);
274 
275 	*groups = pctl->funcs[selector].groups;
276 	*num_groups = pctl->funcs[selector].ngroups;
277 
278 	return 0;
279 }
280 
281 static int axp20x_pmx_set_mux(struct pinctrl_dev *pctldev,
282 			      unsigned int function, unsigned int group)
283 {
284 	struct axp20x_pctl *pctl = pinctrl_dev_get_drvdata(pctldev);
285 	unsigned int mask;
286 
287 	/* Every pin supports GPIO_OUT and GPIO_IN functions */
288 	if (function <= AXP20X_FUNC_GPIO_IN)
289 		return axp20x_pmx_set(pctldev, group,
290 				      pctl->funcs[function].muxval);
291 
292 	if (function == AXP20X_FUNC_LDO)
293 		mask = pctl->desc->ldo_mask;
294 	else
295 		mask = pctl->desc->adc_mask;
296 
297 	if (!(BIT(group) & mask))
298 		return -EINVAL;
299 
300 	/*
301 	 * We let the regulator framework handle the LDO muxing as muxing bits
302 	 * are basically also regulators on/off bits. It's better not to enforce
303 	 * any state of the regulator when selecting LDO mux so that we don't
304 	 * interfere with the regulator driver.
305 	 */
306 	if (function == AXP20X_FUNC_LDO)
307 		return 0;
308 
309 	return axp20x_pmx_set(pctldev, group, pctl->funcs[function].muxval);
310 }
311 
312 static int axp20x_pmx_gpio_set_direction(struct pinctrl_dev *pctldev,
313 					 struct pinctrl_gpio_range *range,
314 					 unsigned int offset, bool input)
315 {
316 	struct axp20x_pctl *pctl = pinctrl_dev_get_drvdata(pctldev);
317 
318 	if (input)
319 		return axp20x_pmx_set(pctldev, offset,
320 				      pctl->funcs[AXP20X_FUNC_GPIO_IN].muxval);
321 
322 	return axp20x_pmx_set(pctldev, offset,
323 			      pctl->funcs[AXP20X_FUNC_GPIO_OUT].muxval);
324 }
325 
326 static const struct pinmux_ops axp20x_pmx_ops = {
327 	.get_functions_count	= axp20x_pmx_func_cnt,
328 	.get_function_name	= axp20x_pmx_func_name,
329 	.get_function_groups	= axp20x_pmx_func_groups,
330 	.set_mux		= axp20x_pmx_set_mux,
331 	.gpio_set_direction	= axp20x_pmx_gpio_set_direction,
332 	.strict			= true,
333 };
334 
335 static int axp20x_groups_cnt(struct pinctrl_dev *pctldev)
336 {
337 	struct axp20x_pctl *pctl = pinctrl_dev_get_drvdata(pctldev);
338 
339 	return pctl->desc->npins;
340 }
341 
342 static int axp20x_group_pins(struct pinctrl_dev *pctldev, unsigned int selector,
343 			     const unsigned int **pins, unsigned int *num_pins)
344 {
345 	struct axp20x_pctl *pctl = pinctrl_dev_get_drvdata(pctldev);
346 
347 	*pins = (unsigned int *)&pctl->desc->pins[selector];
348 	*num_pins = 1;
349 
350 	return 0;
351 }
352 
353 static const char *axp20x_group_name(struct pinctrl_dev *pctldev,
354 				     unsigned int selector)
355 {
356 	struct axp20x_pctl *pctl = pinctrl_dev_get_drvdata(pctldev);
357 
358 	return pctl->desc->pins[selector].name;
359 }
360 
361 static const struct pinctrl_ops axp20x_pctrl_ops = {
362 	.dt_node_to_map		= pinconf_generic_dt_node_to_map_group,
363 	.dt_free_map		= pinconf_generic_dt_free_map,
364 	.get_groups_count	= axp20x_groups_cnt,
365 	.get_group_name		= axp20x_group_name,
366 	.get_group_pins		= axp20x_group_pins,
367 };
368 
369 static int axp20x_funcs_groups_from_mask(struct device *dev, unsigned int mask,
370 					  unsigned int mask_len,
371 					  struct axp20x_pinctrl_function *func,
372 					  const struct pinctrl_pin_desc *pins)
373 {
374 	unsigned long int mask_cpy = mask;
375 	const char **group;
376 	unsigned int ngroups = hweight8(mask);
377 	int bit;
378 
379 	func->ngroups = ngroups;
380 	if (func->ngroups > 0) {
381 		func->groups = devm_kcalloc(dev,
382 					    ngroups, sizeof(const char *),
383 					    GFP_KERNEL);
384 		if (!func->groups)
385 			return -ENOMEM;
386 		group = func->groups;
387 		for_each_set_bit(bit, &mask_cpy, mask_len) {
388 			*group = pins[bit].name;
389 			group++;
390 		}
391 	}
392 
393 	return 0;
394 }
395 
396 static int axp20x_build_funcs_groups(struct platform_device *pdev)
397 {
398 	struct axp20x_pctl *pctl = platform_get_drvdata(pdev);
399 	int i, ret, pin, npins = pctl->desc->npins;
400 
401 	pctl->funcs[AXP20X_FUNC_GPIO_OUT].name = "gpio_out";
402 	pctl->funcs[AXP20X_FUNC_GPIO_OUT].muxval = AXP20X_MUX_GPIO_OUT;
403 	pctl->funcs[AXP20X_FUNC_GPIO_IN].name = "gpio_in";
404 	pctl->funcs[AXP20X_FUNC_GPIO_IN].muxval = AXP20X_MUX_GPIO_IN;
405 	pctl->funcs[AXP20X_FUNC_LDO].name = "ldo";
406 	/*
407 	 * Muxval for LDO is useless as we won't use it.
408 	 * See comment in axp20x_pmx_set_mux.
409 	 */
410 	pctl->funcs[AXP20X_FUNC_ADC].name = "adc";
411 	pctl->funcs[AXP20X_FUNC_ADC].muxval = pctl->desc->adc_mux;
412 
413 	/* Every pin supports GPIO_OUT and GPIO_IN functions */
414 	for (i = 0; i <= AXP20X_FUNC_GPIO_IN; i++) {
415 		pctl->funcs[i].ngroups = npins;
416 		pctl->funcs[i].groups = devm_kcalloc(&pdev->dev,
417 						     npins, sizeof(char *),
418 						     GFP_KERNEL);
419 		if (!pctl->funcs[i].groups)
420 			return -ENOMEM;
421 		for (pin = 0; pin < npins; pin++)
422 			pctl->funcs[i].groups[pin] = pctl->desc->pins[pin].name;
423 	}
424 
425 	ret = axp20x_funcs_groups_from_mask(&pdev->dev, pctl->desc->ldo_mask,
426 				      npins, &pctl->funcs[AXP20X_FUNC_LDO],
427 				      pctl->desc->pins);
428 	if (ret)
429 		return ret;
430 
431 	ret = axp20x_funcs_groups_from_mask(&pdev->dev, pctl->desc->adc_mask,
432 				      npins, &pctl->funcs[AXP20X_FUNC_ADC],
433 				      pctl->desc->pins);
434 	if (ret)
435 		return ret;
436 
437 	return 0;
438 }
439 
440 static const struct of_device_id axp20x_pctl_match[] = {
441 	{ .compatible = "x-powers,axp209-gpio", .data = &axp20x_data, },
442 	{ .compatible = "x-powers,axp221-gpio", .data = &axp22x_data, },
443 	{ .compatible = "x-powers,axp813-gpio", .data = &axp813_data, },
444 	{ }
445 };
446 MODULE_DEVICE_TABLE(of, axp20x_pctl_match);
447 
448 static int axp20x_pctl_probe(struct platform_device *pdev)
449 {
450 	struct axp20x_dev *axp20x = dev_get_drvdata(pdev->dev.parent);
451 	struct axp20x_pctl *pctl;
452 	struct device *dev = &pdev->dev;
453 	struct pinctrl_desc *pctrl_desc;
454 	int ret;
455 
456 	if (!of_device_is_available(pdev->dev.of_node))
457 		return -ENODEV;
458 
459 	if (!axp20x) {
460 		dev_err(&pdev->dev, "Parent drvdata not set\n");
461 		return -EINVAL;
462 	}
463 
464 	pctl = devm_kzalloc(&pdev->dev, sizeof(*pctl), GFP_KERNEL);
465 	if (!pctl)
466 		return -ENOMEM;
467 
468 	pctl->chip.base			= -1;
469 	pctl->chip.can_sleep		= true;
470 	pctl->chip.request		= gpiochip_generic_request;
471 	pctl->chip.free			= gpiochip_generic_free;
472 	pctl->chip.parent		= &pdev->dev;
473 	pctl->chip.label		= dev_name(&pdev->dev);
474 	pctl->chip.owner		= THIS_MODULE;
475 	pctl->chip.get			= axp20x_gpio_get;
476 	pctl->chip.get_direction	= axp20x_gpio_get_direction;
477 	pctl->chip.set			= axp20x_gpio_set;
478 	pctl->chip.direction_input	= axp20x_gpio_input;
479 	pctl->chip.direction_output	= axp20x_gpio_output;
480 
481 	pctl->desc = of_device_get_match_data(dev);
482 
483 	pctl->chip.ngpio		= pctl->desc->npins;
484 
485 	pctl->regmap = axp20x->regmap;
486 	pctl->dev = &pdev->dev;
487 
488 	platform_set_drvdata(pdev, pctl);
489 
490 	ret = axp20x_build_funcs_groups(pdev);
491 	if (ret) {
492 		dev_err(&pdev->dev, "failed to build groups\n");
493 		return ret;
494 	}
495 
496 	pctrl_desc = devm_kzalloc(&pdev->dev, sizeof(*pctrl_desc), GFP_KERNEL);
497 	if (!pctrl_desc)
498 		return -ENOMEM;
499 
500 	pctrl_desc->name = dev_name(&pdev->dev);
501 	pctrl_desc->owner = THIS_MODULE;
502 	pctrl_desc->pins = pctl->desc->pins;
503 	pctrl_desc->npins = pctl->desc->npins;
504 	pctrl_desc->pctlops = &axp20x_pctrl_ops;
505 	pctrl_desc->pmxops = &axp20x_pmx_ops;
506 
507 	pctl->pctl_dev = devm_pinctrl_register(&pdev->dev, pctrl_desc, pctl);
508 	if (IS_ERR(pctl->pctl_dev)) {
509 		dev_err(&pdev->dev, "couldn't register pinctrl driver\n");
510 		return PTR_ERR(pctl->pctl_dev);
511 	}
512 
513 	ret = devm_gpiochip_add_data(&pdev->dev, &pctl->chip, pctl);
514 	if (ret) {
515 		dev_err(&pdev->dev, "Failed to register GPIO chip\n");
516 		return ret;
517 	}
518 
519 	ret = gpiochip_add_pin_range(&pctl->chip, dev_name(&pdev->dev),
520 				     pctl->desc->pins->number,
521 				     pctl->desc->pins->number,
522 				     pctl->desc->npins);
523 	if (ret) {
524 		dev_err(&pdev->dev, "failed to add pin range\n");
525 		return ret;
526 	}
527 
528 	dev_info(&pdev->dev, "AXP209 pinctrl and GPIO driver loaded\n");
529 
530 	return 0;
531 }
532 
533 static struct platform_driver axp20x_pctl_driver = {
534 	.probe		= axp20x_pctl_probe,
535 	.driver = {
536 		.name		= "axp20x-gpio",
537 		.of_match_table	= axp20x_pctl_match,
538 	},
539 };
540 
541 module_platform_driver(axp20x_pctl_driver);
542 
543 MODULE_AUTHOR("Maxime Ripard <maxime.ripard@free-electrons.com>");
544 MODULE_AUTHOR("Quentin Schulz <quentin.schulz@free-electrons.com>");
545 MODULE_DESCRIPTION("AXP20x PMIC pinctrl and GPIO driver");
546 MODULE_LICENSE("GPL");
547