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  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/pinctrl/pinconf-generic.h>
 20#include <linux/pinctrl/pinctrl.h>
 21#include <linux/pinctrl/pinmux.h>
 22#include <linux/platform_device.h>
 23#include <linux/regmap.h>
 24#include <linux/slab.h>
 25
 26#define AXP20X_GPIO_FUNCTIONS		0x7
 27#define AXP20X_GPIO_FUNCTION_OUT_LOW	0
 28#define AXP20X_GPIO_FUNCTION_OUT_HIGH	1
 29#define AXP20X_GPIO_FUNCTION_INPUT	2
 30
 31#define AXP20X_FUNC_GPIO_OUT		0
 32#define AXP20X_FUNC_GPIO_IN		1
 33#define AXP20X_FUNC_LDO			2
 34#define AXP20X_FUNC_ADC			3
 35#define AXP20X_FUNCS_NB			4
 36
 37#define AXP20X_MUX_GPIO_OUT		0
 38#define AXP20X_MUX_GPIO_IN		BIT(1)
 39#define AXP20X_MUX_ADC			BIT(2)
 40
 41#define AXP813_MUX_ADC			(BIT(2) | BIT(0))
 42
 43struct axp20x_pctrl_desc {
 44	const struct pinctrl_pin_desc	*pins;
 45	unsigned int			npins;
 46	/* Stores the pins supporting LDO function. Bit offset is pin number. */
 47	u8				ldo_mask;
 48	/* Stores the pins supporting ADC function. Bit offset is pin number. */
 49	u8				adc_mask;
 50	u8				gpio_status_offset;
 51	u8				adc_mux;
 52};
 53
 54struct axp20x_pinctrl_function {
 55	const char	*name;
 56	unsigned int	muxval;
 57	const char	**groups;
 58	unsigned int	ngroups;
 59};
 60
 61struct axp20x_pctl {
 62	struct gpio_chip	chip;
 63	struct regmap		*regmap;
 64	struct pinctrl_dev			*pctl_dev;
 65	struct device				*dev;
 66	const struct axp20x_pctrl_desc		*desc;
 67	struct axp20x_pinctrl_function		funcs[AXP20X_FUNCS_NB];
 68};
 69
 70static const struct pinctrl_pin_desc axp209_pins[] = {
 71	PINCTRL_PIN(0, "GPIO0"),
 72	PINCTRL_PIN(1, "GPIO1"),
 73	PINCTRL_PIN(2, "GPIO2"),
 74};
 75
 76static const struct pinctrl_pin_desc axp813_pins[] = {
 77	PINCTRL_PIN(0, "GPIO0"),
 78	PINCTRL_PIN(1, "GPIO1"),
 79};
 80
 81static const struct axp20x_pctrl_desc axp20x_data = {
 82	.pins	= axp209_pins,
 83	.npins	= ARRAY_SIZE(axp209_pins),
 84	.ldo_mask = BIT(0) | BIT(1),
 85	.adc_mask = BIT(0) | BIT(1),
 86	.gpio_status_offset = 4,
 87	.adc_mux = AXP20X_MUX_ADC,
 88};
 89
 90static const struct axp20x_pctrl_desc axp813_data = {
 91	.pins	= axp813_pins,
 92	.npins	= ARRAY_SIZE(axp813_pins),
 93	.ldo_mask = BIT(0) | BIT(1),
 94	.adc_mask = BIT(0),
 95	.gpio_status_offset = 0,
 96	.adc_mux = AXP813_MUX_ADC,
 97};
 98
 99static int axp20x_gpio_get_reg(unsigned int offset)
100{
101	switch (offset) {
102	case 0:
103		return AXP20X_GPIO0_CTRL;
104	case 1:
105		return AXP20X_GPIO1_CTRL;
106	case 2:
107		return AXP20X_GPIO2_CTRL;
108	}
109
110	return -EINVAL;
111}
112
113static int axp20x_gpio_input(struct gpio_chip *chip, unsigned int offset)
114{
115	return pinctrl_gpio_direction_input(chip->base + offset);
116}
117
118static int axp20x_gpio_get(struct gpio_chip *chip, unsigned int offset)
119{
120	struct axp20x_pctl *pctl = gpiochip_get_data(chip);
121	unsigned int val;
122	int ret;
123
124	ret = regmap_read(pctl->regmap, AXP20X_GPIO20_SS, &val);
125	if (ret)
126		return ret;
127
128	return !!(val & BIT(offset + pctl->desc->gpio_status_offset));
129}
130
131static int axp20x_gpio_get_direction(struct gpio_chip *chip,
132				     unsigned int offset)
133{
134	struct axp20x_pctl *pctl = gpiochip_get_data(chip);
135	unsigned int val;
136	int reg, ret;
137
138	reg = axp20x_gpio_get_reg(offset);
139	if (reg < 0)
140		return reg;
141
142	ret = regmap_read(pctl->regmap, reg, &val);
143	if (ret)
144		return ret;
145
146	/*
147	 * This shouldn't really happen if the pin is in use already,
148	 * or if it's not in use yet, it doesn't matter since we're
149	 * going to change the value soon anyway. Default to output.
150	 */
151	if ((val & AXP20X_GPIO_FUNCTIONS) > 2)
152		return GPIO_LINE_DIRECTION_OUT;
153
154	/*
155	 * The GPIO directions are the three lowest values.
156	 * 2 is input, 0 and 1 are output
157	 */
158	if (val & 2)
159		return GPIO_LINE_DIRECTION_IN;
160
161	return GPIO_LINE_DIRECTION_OUT;
162}
163
164static int axp20x_gpio_output(struct gpio_chip *chip, unsigned int offset,
165			      int value)
166{
167	chip->set(chip, offset, value);
168
169	return 0;
170}
171
172static void axp20x_gpio_set(struct gpio_chip *chip, unsigned int offset,
173			    int value)
174{
175	struct axp20x_pctl *pctl = gpiochip_get_data(chip);
176	int reg;
177
178	reg = axp20x_gpio_get_reg(offset);
179	if (reg < 0)
180		return;
181
182	regmap_update_bits(pctl->regmap, reg,
183			   AXP20X_GPIO_FUNCTIONS,
184			   value ? AXP20X_GPIO_FUNCTION_OUT_HIGH :
185			   AXP20X_GPIO_FUNCTION_OUT_LOW);
186}
187
188static int axp20x_pmx_set(struct pinctrl_dev *pctldev, unsigned int offset,
189			  u8 config)
190{
191	struct axp20x_pctl *pctl = pinctrl_dev_get_drvdata(pctldev);
192	int reg;
193
194	reg = axp20x_gpio_get_reg(offset);
195	if (reg < 0)
196		return reg;
197
198	return regmap_update_bits(pctl->regmap, reg, AXP20X_GPIO_FUNCTIONS,
199				  config);
200}
201
202static int axp20x_pmx_func_cnt(struct pinctrl_dev *pctldev)
203{
204	struct axp20x_pctl *pctl = pinctrl_dev_get_drvdata(pctldev);
205
206	return ARRAY_SIZE(pctl->funcs);
207}
208
209static const char *axp20x_pmx_func_name(struct pinctrl_dev *pctldev,
210					unsigned int selector)
211{
212	struct axp20x_pctl *pctl = pinctrl_dev_get_drvdata(pctldev);
213
214	return pctl->funcs[selector].name;
215}
216
217static int axp20x_pmx_func_groups(struct pinctrl_dev *pctldev,
218				  unsigned int selector,
219				  const char * const **groups,
220				  unsigned int *num_groups)
221{
222	struct axp20x_pctl *pctl = pinctrl_dev_get_drvdata(pctldev);
223
224	*groups = pctl->funcs[selector].groups;
225	*num_groups = pctl->funcs[selector].ngroups;
226
227	return 0;
228}
229
230static int axp20x_pmx_set_mux(struct pinctrl_dev *pctldev,
231			      unsigned int function, unsigned int group)
232{
233	struct axp20x_pctl *pctl = pinctrl_dev_get_drvdata(pctldev);
234	unsigned int mask;
235
236	/* Every pin supports GPIO_OUT and GPIO_IN functions */
237	if (function <= AXP20X_FUNC_GPIO_IN)
238		return axp20x_pmx_set(pctldev, group,
239				      pctl->funcs[function].muxval);
240
241	if (function == AXP20X_FUNC_LDO)
242		mask = pctl->desc->ldo_mask;
243	else
244		mask = pctl->desc->adc_mask;
245
246	if (!(BIT(group) & mask))
247		return -EINVAL;
248
249	/*
250	 * We let the regulator framework handle the LDO muxing as muxing bits
251	 * are basically also regulators on/off bits. It's better not to enforce
252	 * any state of the regulator when selecting LDO mux so that we don't
253	 * interfere with the regulator driver.
254	 */
255	if (function == AXP20X_FUNC_LDO)
256		return 0;
257
258	return axp20x_pmx_set(pctldev, group, pctl->funcs[function].muxval);
259}
260
261static int axp20x_pmx_gpio_set_direction(struct pinctrl_dev *pctldev,
262					 struct pinctrl_gpio_range *range,
263					 unsigned int offset, bool input)
264{
265	struct axp20x_pctl *pctl = pinctrl_dev_get_drvdata(pctldev);
266
267	if (input)
268		return axp20x_pmx_set(pctldev, offset,
269				      pctl->funcs[AXP20X_FUNC_GPIO_IN].muxval);
270
271	return axp20x_pmx_set(pctldev, offset,
272			      pctl->funcs[AXP20X_FUNC_GPIO_OUT].muxval);
273}
274
275static const struct pinmux_ops axp20x_pmx_ops = {
276	.get_functions_count	= axp20x_pmx_func_cnt,
277	.get_function_name	= axp20x_pmx_func_name,
278	.get_function_groups	= axp20x_pmx_func_groups,
279	.set_mux		= axp20x_pmx_set_mux,
280	.gpio_set_direction	= axp20x_pmx_gpio_set_direction,
281	.strict			= true,
282};
283
284static int axp20x_groups_cnt(struct pinctrl_dev *pctldev)
285{
286	struct axp20x_pctl *pctl = pinctrl_dev_get_drvdata(pctldev);
287
288	return pctl->desc->npins;
289}
290
291static int axp20x_group_pins(struct pinctrl_dev *pctldev, unsigned int selector,
292			     const unsigned int **pins, unsigned int *num_pins)
293{
294	struct axp20x_pctl *pctl = pinctrl_dev_get_drvdata(pctldev);
295
296	*pins = (unsigned int *)&pctl->desc->pins[selector];
297	*num_pins = 1;
298
299	return 0;
300}
301
302static const char *axp20x_group_name(struct pinctrl_dev *pctldev,
303				     unsigned int selector)
304{
305	struct axp20x_pctl *pctl = pinctrl_dev_get_drvdata(pctldev);
306
307	return pctl->desc->pins[selector].name;
308}
309
310static const struct pinctrl_ops axp20x_pctrl_ops = {
311	.dt_node_to_map		= pinconf_generic_dt_node_to_map_group,
312	.dt_free_map		= pinconf_generic_dt_free_map,
313	.get_groups_count	= axp20x_groups_cnt,
314	.get_group_name		= axp20x_group_name,
315	.get_group_pins		= axp20x_group_pins,
316};
317
318static int axp20x_funcs_groups_from_mask(struct device *dev, unsigned int mask,
319					  unsigned int mask_len,
320					  struct axp20x_pinctrl_function *func,
321					  const struct pinctrl_pin_desc *pins)
322{
323	unsigned long int mask_cpy = mask;
324	const char **group;
325	unsigned int ngroups = hweight8(mask);
326	int bit;
327
328	func->ngroups = ngroups;
329	if (func->ngroups > 0) {
330		func->groups = devm_kcalloc(dev,
331					    ngroups, sizeof(const char *),
332					    GFP_KERNEL);
333		if (!func->groups)
334			return -ENOMEM;
335		group = func->groups;
336		for_each_set_bit(bit, &mask_cpy, mask_len) {
337			*group = pins[bit].name;
338			group++;
339		}
340	}
341
342	return 0;
343}
344
345static int axp20x_build_funcs_groups(struct platform_device *pdev)
346{
347	struct axp20x_pctl *pctl = platform_get_drvdata(pdev);
348	int i, ret, pin, npins = pctl->desc->npins;
349
350	pctl->funcs[AXP20X_FUNC_GPIO_OUT].name = "gpio_out";
351	pctl->funcs[AXP20X_FUNC_GPIO_OUT].muxval = AXP20X_MUX_GPIO_OUT;
352	pctl->funcs[AXP20X_FUNC_GPIO_IN].name = "gpio_in";
353	pctl->funcs[AXP20X_FUNC_GPIO_IN].muxval = AXP20X_MUX_GPIO_IN;
354	pctl->funcs[AXP20X_FUNC_LDO].name = "ldo";
355	/*
356	 * Muxval for LDO is useless as we won't use it.
357	 * See comment in axp20x_pmx_set_mux.
358	 */
359	pctl->funcs[AXP20X_FUNC_ADC].name = "adc";
360	pctl->funcs[AXP20X_FUNC_ADC].muxval = pctl->desc->adc_mux;
361
362	/* Every pin supports GPIO_OUT and GPIO_IN functions */
363	for (i = 0; i <= AXP20X_FUNC_GPIO_IN; i++) {
364		pctl->funcs[i].ngroups = npins;
365		pctl->funcs[i].groups = devm_kcalloc(&pdev->dev,
366						     npins, sizeof(char *),
367						     GFP_KERNEL);
368		if (!pctl->funcs[i].groups)
369			return -ENOMEM;
370		for (pin = 0; pin < npins; pin++)
371			pctl->funcs[i].groups[pin] = pctl->desc->pins[pin].name;
372	}
373
374	ret = axp20x_funcs_groups_from_mask(&pdev->dev, pctl->desc->ldo_mask,
375				      npins, &pctl->funcs[AXP20X_FUNC_LDO],
376				      pctl->desc->pins);
377	if (ret)
378		return ret;
379
380	ret = axp20x_funcs_groups_from_mask(&pdev->dev, pctl->desc->adc_mask,
381				      npins, &pctl->funcs[AXP20X_FUNC_ADC],
382				      pctl->desc->pins);
383	if (ret)
384		return ret;
385
386	return 0;
387}
388
389static const struct of_device_id axp20x_pctl_match[] = {
390	{ .compatible = "x-powers,axp209-gpio", .data = &axp20x_data, },
391	{ .compatible = "x-powers,axp813-gpio", .data = &axp813_data, },
392	{ }
393};
394MODULE_DEVICE_TABLE(of, axp20x_pctl_match);
395
396static int axp20x_pctl_probe(struct platform_device *pdev)
397{
398	struct axp20x_dev *axp20x = dev_get_drvdata(pdev->dev.parent);
399	struct axp20x_pctl *pctl;
400	struct device *dev = &pdev->dev;
401	struct pinctrl_desc *pctrl_desc;
402	int ret;
403
404	if (!of_device_is_available(pdev->dev.of_node))
405		return -ENODEV;
406
407	if (!axp20x) {
408		dev_err(&pdev->dev, "Parent drvdata not set\n");
409		return -EINVAL;
410	}
411
412	pctl = devm_kzalloc(&pdev->dev, sizeof(*pctl), GFP_KERNEL);
413	if (!pctl)
414		return -ENOMEM;
415
416	pctl->chip.base			= -1;
417	pctl->chip.can_sleep		= true;
418	pctl->chip.request		= gpiochip_generic_request;
419	pctl->chip.free			= gpiochip_generic_free;
420	pctl->chip.parent		= &pdev->dev;
421	pctl->chip.label		= dev_name(&pdev->dev);
422	pctl->chip.owner		= THIS_MODULE;
423	pctl->chip.get			= axp20x_gpio_get;
424	pctl->chip.get_direction	= axp20x_gpio_get_direction;
425	pctl->chip.set			= axp20x_gpio_set;
426	pctl->chip.direction_input	= axp20x_gpio_input;
427	pctl->chip.direction_output	= axp20x_gpio_output;
428
429	pctl->desc = of_device_get_match_data(dev);
430
431	pctl->chip.ngpio		= pctl->desc->npins;
432
433	pctl->regmap = axp20x->regmap;
434	pctl->dev = &pdev->dev;
435
436	platform_set_drvdata(pdev, pctl);
437
438	ret = axp20x_build_funcs_groups(pdev);
439	if (ret) {
440		dev_err(&pdev->dev, "failed to build groups\n");
441		return ret;
442	}
443
444	pctrl_desc = devm_kzalloc(&pdev->dev, sizeof(*pctrl_desc), GFP_KERNEL);
445	if (!pctrl_desc)
446		return -ENOMEM;
447
448	pctrl_desc->name = dev_name(&pdev->dev);
449	pctrl_desc->owner = THIS_MODULE;
450	pctrl_desc->pins = pctl->desc->pins;
451	pctrl_desc->npins = pctl->desc->npins;
452	pctrl_desc->pctlops = &axp20x_pctrl_ops;
453	pctrl_desc->pmxops = &axp20x_pmx_ops;
454
455	pctl->pctl_dev = devm_pinctrl_register(&pdev->dev, pctrl_desc, pctl);
456	if (IS_ERR(pctl->pctl_dev)) {
457		dev_err(&pdev->dev, "couldn't register pinctrl driver\n");
458		return PTR_ERR(pctl->pctl_dev);
459	}
460
461	ret = devm_gpiochip_add_data(&pdev->dev, &pctl->chip, pctl);
462	if (ret) {
463		dev_err(&pdev->dev, "Failed to register GPIO chip\n");
464		return ret;
465	}
466
467	ret = gpiochip_add_pin_range(&pctl->chip, dev_name(&pdev->dev),
468				     pctl->desc->pins->number,
469				     pctl->desc->pins->number,
470				     pctl->desc->npins);
471	if (ret) {
472		dev_err(&pdev->dev, "failed to add pin range\n");
473		return ret;
474	}
475
476	dev_info(&pdev->dev, "AXP209 pinctrl and GPIO driver loaded\n");
477
478	return 0;
479}
480
481static struct platform_driver axp20x_pctl_driver = {
482	.probe		= axp20x_pctl_probe,
483	.driver = {
484		.name		= "axp20x-gpio",
485		.of_match_table	= axp20x_pctl_match,
486	},
487};
488
489module_platform_driver(axp20x_pctl_driver);
490
491MODULE_AUTHOR("Maxime Ripard <maxime.ripard@free-electrons.com>");
492MODULE_AUTHOR("Quentin Schulz <quentin.schulz@free-electrons.com>");
493MODULE_DESCRIPTION("AXP20x PMIC pinctrl and GPIO driver");
494MODULE_LICENSE("GPL");