xref: /linux/drivers/pinctrl/pinctrl-axp209.c (revision 0e9ab8e4d44ae9d9aaf213bfd2c90bbe7289337b)
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_FUNC_GPIO_OUT		0
34 #define AXP20X_FUNC_GPIO_IN		1
35 #define AXP20X_FUNC_LDO			2
36 #define AXP20X_FUNC_ADC			3
37 #define AXP20X_FUNCS_NB			4
38 
39 #define AXP20X_MUX_GPIO_OUT		0
40 #define AXP20X_MUX_GPIO_IN		BIT(1)
41 #define AXP20X_MUX_ADC			BIT(2)
42 
43 #define AXP813_MUX_ADC			(BIT(2) | BIT(0))
44 
45 struct axp20x_pctrl_desc {
46 	const struct pinctrl_pin_desc	*pins;
47 	unsigned int			npins;
48 	/* Stores the pins supporting LDO function. Bit offset is pin number. */
49 	u8				ldo_mask;
50 	/* Stores the pins supporting ADC function. Bit offset is pin number. */
51 	u8				adc_mask;
52 	u8				gpio_status_offset;
53 	u8				adc_mux;
54 };
55 
56 struct axp20x_pinctrl_function {
57 	const char	*name;
58 	unsigned int	muxval;
59 	const char	**groups;
60 	unsigned int	ngroups;
61 };
62 
63 struct axp20x_pctl {
64 	struct gpio_chip	chip;
65 	struct regmap		*regmap;
66 	struct pinctrl_dev			*pctl_dev;
67 	struct device				*dev;
68 	const struct axp20x_pctrl_desc		*desc;
69 	struct axp20x_pinctrl_function		funcs[AXP20X_FUNCS_NB];
70 };
71 
72 static const struct pinctrl_pin_desc axp209_pins[] = {
73 	PINCTRL_PIN(0, "GPIO0"),
74 	PINCTRL_PIN(1, "GPIO1"),
75 	PINCTRL_PIN(2, "GPIO2"),
76 };
77 
78 static const struct pinctrl_pin_desc axp22x_pins[] = {
79 	PINCTRL_PIN(0, "GPIO0"),
80 	PINCTRL_PIN(1, "GPIO1"),
81 };
82 
83 static const struct axp20x_pctrl_desc axp20x_data = {
84 	.pins	= axp209_pins,
85 	.npins	= ARRAY_SIZE(axp209_pins),
86 	.ldo_mask = BIT(0) | BIT(1),
87 	.adc_mask = BIT(0) | BIT(1),
88 	.gpio_status_offset = 4,
89 	.adc_mux = AXP20X_MUX_ADC,
90 };
91 
92 static const struct axp20x_pctrl_desc axp22x_data = {
93 	.pins	= axp22x_pins,
94 	.npins	= ARRAY_SIZE(axp22x_pins),
95 	.ldo_mask = BIT(0) | BIT(1),
96 	.gpio_status_offset = 0,
97 };
98 
99 static const struct axp20x_pctrl_desc axp813_data = {
100 	.pins	= axp22x_pins,
101 	.npins	= ARRAY_SIZE(axp22x_pins),
102 	.ldo_mask = BIT(0) | BIT(1),
103 	.adc_mask = BIT(0),
104 	.gpio_status_offset = 0,
105 	.adc_mux = AXP813_MUX_ADC,
106 };
107 
108 static int axp20x_gpio_get_reg(unsigned int offset)
109 {
110 	switch (offset) {
111 	case 0:
112 		return AXP20X_GPIO0_CTRL;
113 	case 1:
114 		return AXP20X_GPIO1_CTRL;
115 	case 2:
116 		return AXP20X_GPIO2_CTRL;
117 	}
118 
119 	return -EINVAL;
120 }
121 
122 static int axp20x_gpio_input(struct gpio_chip *chip, unsigned int offset)
123 {
124 	return pinctrl_gpio_direction_input(chip->base + offset);
125 }
126 
127 static int axp20x_gpio_get(struct gpio_chip *chip, unsigned int offset)
128 {
129 	struct axp20x_pctl *pctl = gpiochip_get_data(chip);
130 	unsigned int val;
131 	int ret;
132 
133 	ret = regmap_read(pctl->regmap, AXP20X_GPIO20_SS, &val);
134 	if (ret)
135 		return ret;
136 
137 	return !!(val & BIT(offset + pctl->desc->gpio_status_offset));
138 }
139 
140 static int axp20x_gpio_get_direction(struct gpio_chip *chip,
141 				     unsigned int offset)
142 {
143 	struct axp20x_pctl *pctl = gpiochip_get_data(chip);
144 	unsigned int val;
145 	int reg, ret;
146 
147 	reg = axp20x_gpio_get_reg(offset);
148 	if (reg < 0)
149 		return reg;
150 
151 	ret = regmap_read(pctl->regmap, reg, &val);
152 	if (ret)
153 		return ret;
154 
155 	/*
156 	 * This shouldn't really happen if the pin is in use already,
157 	 * or if it's not in use yet, it doesn't matter since we're
158 	 * going to change the value soon anyway. Default to output.
159 	 */
160 	if ((val & AXP20X_GPIO_FUNCTIONS) > 2)
161 		return GPIO_LINE_DIRECTION_OUT;
162 
163 	/*
164 	 * The GPIO directions are the three lowest values.
165 	 * 2 is input, 0 and 1 are output
166 	 */
167 	if (val & 2)
168 		return GPIO_LINE_DIRECTION_IN;
169 
170 	return GPIO_LINE_DIRECTION_OUT;
171 }
172 
173 static int axp20x_gpio_output(struct gpio_chip *chip, unsigned int offset,
174 			      int value)
175 {
176 	chip->set(chip, offset, value);
177 
178 	return 0;
179 }
180 
181 static void axp20x_gpio_set(struct gpio_chip *chip, unsigned int offset,
182 			    int value)
183 {
184 	struct axp20x_pctl *pctl = gpiochip_get_data(chip);
185 	int reg;
186 
187 	reg = axp20x_gpio_get_reg(offset);
188 	if (reg < 0)
189 		return;
190 
191 	regmap_update_bits(pctl->regmap, reg,
192 			   AXP20X_GPIO_FUNCTIONS,
193 			   value ? AXP20X_GPIO_FUNCTION_OUT_HIGH :
194 			   AXP20X_GPIO_FUNCTION_OUT_LOW);
195 }
196 
197 static int axp20x_pmx_set(struct pinctrl_dev *pctldev, unsigned int offset,
198 			  u8 config)
199 {
200 	struct axp20x_pctl *pctl = pinctrl_dev_get_drvdata(pctldev);
201 	int reg;
202 
203 	reg = axp20x_gpio_get_reg(offset);
204 	if (reg < 0)
205 		return reg;
206 
207 	return regmap_update_bits(pctl->regmap, reg, AXP20X_GPIO_FUNCTIONS,
208 				  config);
209 }
210 
211 static int axp20x_pmx_func_cnt(struct pinctrl_dev *pctldev)
212 {
213 	struct axp20x_pctl *pctl = pinctrl_dev_get_drvdata(pctldev);
214 
215 	return ARRAY_SIZE(pctl->funcs);
216 }
217 
218 static const char *axp20x_pmx_func_name(struct pinctrl_dev *pctldev,
219 					unsigned int selector)
220 {
221 	struct axp20x_pctl *pctl = pinctrl_dev_get_drvdata(pctldev);
222 
223 	return pctl->funcs[selector].name;
224 }
225 
226 static int axp20x_pmx_func_groups(struct pinctrl_dev *pctldev,
227 				  unsigned int selector,
228 				  const char * const **groups,
229 				  unsigned int *num_groups)
230 {
231 	struct axp20x_pctl *pctl = pinctrl_dev_get_drvdata(pctldev);
232 
233 	*groups = pctl->funcs[selector].groups;
234 	*num_groups = pctl->funcs[selector].ngroups;
235 
236 	return 0;
237 }
238 
239 static int axp20x_pmx_set_mux(struct pinctrl_dev *pctldev,
240 			      unsigned int function, unsigned int group)
241 {
242 	struct axp20x_pctl *pctl = pinctrl_dev_get_drvdata(pctldev);
243 	unsigned int mask;
244 
245 	/* Every pin supports GPIO_OUT and GPIO_IN functions */
246 	if (function <= AXP20X_FUNC_GPIO_IN)
247 		return axp20x_pmx_set(pctldev, group,
248 				      pctl->funcs[function].muxval);
249 
250 	if (function == AXP20X_FUNC_LDO)
251 		mask = pctl->desc->ldo_mask;
252 	else
253 		mask = pctl->desc->adc_mask;
254 
255 	if (!(BIT(group) & mask))
256 		return -EINVAL;
257 
258 	/*
259 	 * We let the regulator framework handle the LDO muxing as muxing bits
260 	 * are basically also regulators on/off bits. It's better not to enforce
261 	 * any state of the regulator when selecting LDO mux so that we don't
262 	 * interfere with the regulator driver.
263 	 */
264 	if (function == AXP20X_FUNC_LDO)
265 		return 0;
266 
267 	return axp20x_pmx_set(pctldev, group, pctl->funcs[function].muxval);
268 }
269 
270 static int axp20x_pmx_gpio_set_direction(struct pinctrl_dev *pctldev,
271 					 struct pinctrl_gpio_range *range,
272 					 unsigned int offset, bool input)
273 {
274 	struct axp20x_pctl *pctl = pinctrl_dev_get_drvdata(pctldev);
275 
276 	if (input)
277 		return axp20x_pmx_set(pctldev, offset,
278 				      pctl->funcs[AXP20X_FUNC_GPIO_IN].muxval);
279 
280 	return axp20x_pmx_set(pctldev, offset,
281 			      pctl->funcs[AXP20X_FUNC_GPIO_OUT].muxval);
282 }
283 
284 static const struct pinmux_ops axp20x_pmx_ops = {
285 	.get_functions_count	= axp20x_pmx_func_cnt,
286 	.get_function_name	= axp20x_pmx_func_name,
287 	.get_function_groups	= axp20x_pmx_func_groups,
288 	.set_mux		= axp20x_pmx_set_mux,
289 	.gpio_set_direction	= axp20x_pmx_gpio_set_direction,
290 	.strict			= true,
291 };
292 
293 static int axp20x_groups_cnt(struct pinctrl_dev *pctldev)
294 {
295 	struct axp20x_pctl *pctl = pinctrl_dev_get_drvdata(pctldev);
296 
297 	return pctl->desc->npins;
298 }
299 
300 static int axp20x_group_pins(struct pinctrl_dev *pctldev, unsigned int selector,
301 			     const unsigned int **pins, unsigned int *num_pins)
302 {
303 	struct axp20x_pctl *pctl = pinctrl_dev_get_drvdata(pctldev);
304 
305 	*pins = (unsigned int *)&pctl->desc->pins[selector];
306 	*num_pins = 1;
307 
308 	return 0;
309 }
310 
311 static const char *axp20x_group_name(struct pinctrl_dev *pctldev,
312 				     unsigned int selector)
313 {
314 	struct axp20x_pctl *pctl = pinctrl_dev_get_drvdata(pctldev);
315 
316 	return pctl->desc->pins[selector].name;
317 }
318 
319 static const struct pinctrl_ops axp20x_pctrl_ops = {
320 	.dt_node_to_map		= pinconf_generic_dt_node_to_map_group,
321 	.dt_free_map		= pinconf_generic_dt_free_map,
322 	.get_groups_count	= axp20x_groups_cnt,
323 	.get_group_name		= axp20x_group_name,
324 	.get_group_pins		= axp20x_group_pins,
325 };
326 
327 static int axp20x_funcs_groups_from_mask(struct device *dev, unsigned int mask,
328 					  unsigned int mask_len,
329 					  struct axp20x_pinctrl_function *func,
330 					  const struct pinctrl_pin_desc *pins)
331 {
332 	unsigned long int mask_cpy = mask;
333 	const char **group;
334 	unsigned int ngroups = hweight8(mask);
335 	int bit;
336 
337 	func->ngroups = ngroups;
338 	if (func->ngroups > 0) {
339 		func->groups = devm_kcalloc(dev,
340 					    ngroups, sizeof(const char *),
341 					    GFP_KERNEL);
342 		if (!func->groups)
343 			return -ENOMEM;
344 		group = func->groups;
345 		for_each_set_bit(bit, &mask_cpy, mask_len) {
346 			*group = pins[bit].name;
347 			group++;
348 		}
349 	}
350 
351 	return 0;
352 }
353 
354 static int axp20x_build_funcs_groups(struct platform_device *pdev)
355 {
356 	struct axp20x_pctl *pctl = platform_get_drvdata(pdev);
357 	int i, ret, pin, npins = pctl->desc->npins;
358 
359 	pctl->funcs[AXP20X_FUNC_GPIO_OUT].name = "gpio_out";
360 	pctl->funcs[AXP20X_FUNC_GPIO_OUT].muxval = AXP20X_MUX_GPIO_OUT;
361 	pctl->funcs[AXP20X_FUNC_GPIO_IN].name = "gpio_in";
362 	pctl->funcs[AXP20X_FUNC_GPIO_IN].muxval = AXP20X_MUX_GPIO_IN;
363 	pctl->funcs[AXP20X_FUNC_LDO].name = "ldo";
364 	/*
365 	 * Muxval for LDO is useless as we won't use it.
366 	 * See comment in axp20x_pmx_set_mux.
367 	 */
368 	pctl->funcs[AXP20X_FUNC_ADC].name = "adc";
369 	pctl->funcs[AXP20X_FUNC_ADC].muxval = pctl->desc->adc_mux;
370 
371 	/* Every pin supports GPIO_OUT and GPIO_IN functions */
372 	for (i = 0; i <= AXP20X_FUNC_GPIO_IN; i++) {
373 		pctl->funcs[i].ngroups = npins;
374 		pctl->funcs[i].groups = devm_kcalloc(&pdev->dev,
375 						     npins, sizeof(char *),
376 						     GFP_KERNEL);
377 		if (!pctl->funcs[i].groups)
378 			return -ENOMEM;
379 		for (pin = 0; pin < npins; pin++)
380 			pctl->funcs[i].groups[pin] = pctl->desc->pins[pin].name;
381 	}
382 
383 	ret = axp20x_funcs_groups_from_mask(&pdev->dev, pctl->desc->ldo_mask,
384 				      npins, &pctl->funcs[AXP20X_FUNC_LDO],
385 				      pctl->desc->pins);
386 	if (ret)
387 		return ret;
388 
389 	ret = axp20x_funcs_groups_from_mask(&pdev->dev, pctl->desc->adc_mask,
390 				      npins, &pctl->funcs[AXP20X_FUNC_ADC],
391 				      pctl->desc->pins);
392 	if (ret)
393 		return ret;
394 
395 	return 0;
396 }
397 
398 static const struct of_device_id axp20x_pctl_match[] = {
399 	{ .compatible = "x-powers,axp209-gpio", .data = &axp20x_data, },
400 	{ .compatible = "x-powers,axp221-gpio", .data = &axp22x_data, },
401 	{ .compatible = "x-powers,axp813-gpio", .data = &axp813_data, },
402 	{ }
403 };
404 MODULE_DEVICE_TABLE(of, axp20x_pctl_match);
405 
406 static int axp20x_pctl_probe(struct platform_device *pdev)
407 {
408 	struct axp20x_dev *axp20x = dev_get_drvdata(pdev->dev.parent);
409 	struct axp20x_pctl *pctl;
410 	struct device *dev = &pdev->dev;
411 	struct pinctrl_desc *pctrl_desc;
412 	int ret;
413 
414 	if (!of_device_is_available(pdev->dev.of_node))
415 		return -ENODEV;
416 
417 	if (!axp20x) {
418 		dev_err(&pdev->dev, "Parent drvdata not set\n");
419 		return -EINVAL;
420 	}
421 
422 	pctl = devm_kzalloc(&pdev->dev, sizeof(*pctl), GFP_KERNEL);
423 	if (!pctl)
424 		return -ENOMEM;
425 
426 	pctl->chip.base			= -1;
427 	pctl->chip.can_sleep		= true;
428 	pctl->chip.request		= gpiochip_generic_request;
429 	pctl->chip.free			= gpiochip_generic_free;
430 	pctl->chip.parent		= &pdev->dev;
431 	pctl->chip.label		= dev_name(&pdev->dev);
432 	pctl->chip.owner		= THIS_MODULE;
433 	pctl->chip.get			= axp20x_gpio_get;
434 	pctl->chip.get_direction	= axp20x_gpio_get_direction;
435 	pctl->chip.set			= axp20x_gpio_set;
436 	pctl->chip.direction_input	= axp20x_gpio_input;
437 	pctl->chip.direction_output	= axp20x_gpio_output;
438 
439 	pctl->desc = of_device_get_match_data(dev);
440 
441 	pctl->chip.ngpio		= pctl->desc->npins;
442 
443 	pctl->regmap = axp20x->regmap;
444 	pctl->dev = &pdev->dev;
445 
446 	platform_set_drvdata(pdev, pctl);
447 
448 	ret = axp20x_build_funcs_groups(pdev);
449 	if (ret) {
450 		dev_err(&pdev->dev, "failed to build groups\n");
451 		return ret;
452 	}
453 
454 	pctrl_desc = devm_kzalloc(&pdev->dev, sizeof(*pctrl_desc), GFP_KERNEL);
455 	if (!pctrl_desc)
456 		return -ENOMEM;
457 
458 	pctrl_desc->name = dev_name(&pdev->dev);
459 	pctrl_desc->owner = THIS_MODULE;
460 	pctrl_desc->pins = pctl->desc->pins;
461 	pctrl_desc->npins = pctl->desc->npins;
462 	pctrl_desc->pctlops = &axp20x_pctrl_ops;
463 	pctrl_desc->pmxops = &axp20x_pmx_ops;
464 
465 	pctl->pctl_dev = devm_pinctrl_register(&pdev->dev, pctrl_desc, pctl);
466 	if (IS_ERR(pctl->pctl_dev)) {
467 		dev_err(&pdev->dev, "couldn't register pinctrl driver\n");
468 		return PTR_ERR(pctl->pctl_dev);
469 	}
470 
471 	ret = devm_gpiochip_add_data(&pdev->dev, &pctl->chip, pctl);
472 	if (ret) {
473 		dev_err(&pdev->dev, "Failed to register GPIO chip\n");
474 		return ret;
475 	}
476 
477 	ret = gpiochip_add_pin_range(&pctl->chip, dev_name(&pdev->dev),
478 				     pctl->desc->pins->number,
479 				     pctl->desc->pins->number,
480 				     pctl->desc->npins);
481 	if (ret) {
482 		dev_err(&pdev->dev, "failed to add pin range\n");
483 		return ret;
484 	}
485 
486 	dev_info(&pdev->dev, "AXP209 pinctrl and GPIO driver loaded\n");
487 
488 	return 0;
489 }
490 
491 static struct platform_driver axp20x_pctl_driver = {
492 	.probe		= axp20x_pctl_probe,
493 	.driver = {
494 		.name		= "axp20x-gpio",
495 		.of_match_table	= axp20x_pctl_match,
496 	},
497 };
498 
499 module_platform_driver(axp20x_pctl_driver);
500 
501 MODULE_AUTHOR("Maxime Ripard <maxime.ripard@free-electrons.com>");
502 MODULE_AUTHOR("Quentin Schulz <quentin.schulz@free-electrons.com>");
503 MODULE_DESCRIPTION("AXP20x PMIC pinctrl and GPIO driver");
504 MODULE_LICENSE("GPL");
505