xref: /linux/drivers/pinctrl/qcom/pinctrl-lpass-lpi.c (revision 30bbcb44707a97fcb62246bebc8b413b5ab293f8)
1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3  * Copyright (c) 2016-2019, The Linux Foundation. All rights reserved.
4  * Copyright (c) 2020 Linaro Ltd.
5  */
6 
7 #include <linux/bitfield.h>
8 #include <linux/clk.h>
9 #include <linux/gpio/driver.h>
10 #include <linux/module.h>
11 #include <linux/of.h>
12 #include <linux/platform_device.h>
13 #include <linux/seq_file.h>
14 
15 #include <linux/pinctrl/pinconf-generic.h>
16 #include <linux/pinctrl/pinconf.h>
17 #include <linux/pinctrl/pinmux.h>
18 
19 #include "../pinctrl-utils.h"
20 
21 #include "pinctrl-lpass-lpi.h"
22 
23 #define MAX_NR_GPIO		32
24 #define GPIO_FUNC		0
25 #define MAX_LPI_NUM_CLKS	2
26 
27 struct lpi_pinctrl {
28 	struct device *dev;
29 	struct pinctrl_dev *ctrl;
30 	struct gpio_chip chip;
31 	struct pinctrl_desc desc;
32 	char __iomem *tlmm_base;
33 	char __iomem *slew_base;
34 	struct clk_bulk_data clks[MAX_LPI_NUM_CLKS];
35 	/* Protects from concurrent register updates */
36 	struct mutex lock;
37 	DECLARE_BITMAP(ever_gpio, MAX_NR_GPIO);
38 	const struct lpi_pinctrl_variant_data *data;
39 };
40 
41 static int lpi_gpio_read(struct lpi_pinctrl *state, unsigned int pin,
42 			 unsigned int addr)
43 {
44 	u32 pin_offset;
45 
46 	if (state->data->flags & LPI_FLAG_USE_PREDEFINED_PIN_OFFSET)
47 		pin_offset = state->data->groups[pin].pin_offset;
48 	else
49 		pin_offset = LPI_TLMM_REG_OFFSET * pin;
50 
51 	return ioread32(state->tlmm_base + pin_offset + addr);
52 }
53 
54 static int lpi_gpio_write(struct lpi_pinctrl *state, unsigned int pin,
55 			  unsigned int addr, unsigned int val)
56 {
57 	u32 pin_offset;
58 
59 	if (state->data->flags & LPI_FLAG_USE_PREDEFINED_PIN_OFFSET)
60 		pin_offset = state->data->groups[pin].pin_offset;
61 	else
62 		pin_offset = LPI_TLMM_REG_OFFSET * pin;
63 
64 	iowrite32(val, state->tlmm_base + pin_offset + addr);
65 
66 	return 0;
67 }
68 
69 static const struct pinctrl_ops lpi_gpio_pinctrl_ops = {
70 	.get_groups_count	= pinctrl_generic_get_group_count,
71 	.get_group_name		= pinctrl_generic_get_group_name,
72 	.get_group_pins		= pinctrl_generic_get_group_pins,
73 	.dt_node_to_map		= pinconf_generic_dt_node_to_map_group,
74 	.dt_free_map		= pinctrl_utils_free_map,
75 };
76 
77 static int lpi_gpio_get_functions_count(struct pinctrl_dev *pctldev)
78 {
79 	struct lpi_pinctrl *pctrl = pinctrl_dev_get_drvdata(pctldev);
80 
81 	return pctrl->data->nfunctions;
82 }
83 
84 static const char *lpi_gpio_get_function_name(struct pinctrl_dev *pctldev,
85 					      unsigned int function)
86 {
87 	struct lpi_pinctrl *pctrl = pinctrl_dev_get_drvdata(pctldev);
88 
89 	return pctrl->data->functions[function].name;
90 }
91 
92 static int lpi_gpio_get_function_groups(struct pinctrl_dev *pctldev,
93 					unsigned int function,
94 					const char *const **groups,
95 					unsigned *const num_qgroups)
96 {
97 	struct lpi_pinctrl *pctrl = pinctrl_dev_get_drvdata(pctldev);
98 
99 	*groups = pctrl->data->functions[function].groups;
100 	*num_qgroups = pctrl->data->functions[function].ngroups;
101 
102 	return 0;
103 }
104 
105 static int lpi_gpio_set_mux(struct pinctrl_dev *pctldev, unsigned int function,
106 			    unsigned int group)
107 {
108 	struct lpi_pinctrl *pctrl = pinctrl_dev_get_drvdata(pctldev);
109 	const struct lpi_pingroup *g = &pctrl->data->groups[group];
110 	u32 val;
111 	int i, pin = g->pin;
112 
113 	for (i = 0; i < g->nfuncs; i++) {
114 		if (g->funcs[i] == function)
115 			break;
116 	}
117 
118 	if (WARN_ON(i == g->nfuncs))
119 		return -EINVAL;
120 
121 	mutex_lock(&pctrl->lock);
122 	val = lpi_gpio_read(pctrl, pin, LPI_GPIO_CFG_REG);
123 
124 	/*
125 	 * If this is the first time muxing to GPIO and the direction is
126 	 * output, make sure that we're not going to be glitching the pin
127 	 * by reading the current state of the pin and setting it as the
128 	 * output.
129 	 */
130 	if (i == GPIO_FUNC && (val & LPI_GPIO_OE_MASK) &&
131 	    !test_and_set_bit(group, pctrl->ever_gpio)) {
132 		u32 io_val = lpi_gpio_read(pctrl, group, LPI_GPIO_VALUE_REG);
133 
134 		if (io_val & LPI_GPIO_VALUE_IN_MASK) {
135 			if (!(io_val & LPI_GPIO_VALUE_OUT_MASK))
136 				lpi_gpio_write(pctrl, group, LPI_GPIO_VALUE_REG,
137 					       io_val | LPI_GPIO_VALUE_OUT_MASK);
138 		} else {
139 			if (io_val & LPI_GPIO_VALUE_OUT_MASK)
140 				lpi_gpio_write(pctrl, group, LPI_GPIO_VALUE_REG,
141 					       io_val & ~LPI_GPIO_VALUE_OUT_MASK);
142 		}
143 	}
144 
145 	u32p_replace_bits(&val, i, LPI_GPIO_FUNCTION_MASK);
146 	lpi_gpio_write(pctrl, pin, LPI_GPIO_CFG_REG, val);
147 	mutex_unlock(&pctrl->lock);
148 
149 	return 0;
150 }
151 
152 static const struct pinmux_ops lpi_gpio_pinmux_ops = {
153 	.get_functions_count	= lpi_gpio_get_functions_count,
154 	.get_function_name	= lpi_gpio_get_function_name,
155 	.get_function_groups	= lpi_gpio_get_function_groups,
156 	.set_mux		= lpi_gpio_set_mux,
157 };
158 
159 static int lpi_config_get(struct pinctrl_dev *pctldev,
160 			  unsigned int pin, unsigned long *config)
161 {
162 	unsigned int param = pinconf_to_config_param(*config);
163 	struct lpi_pinctrl *state = dev_get_drvdata(pctldev->dev);
164 	unsigned int arg = 0;
165 	int is_out;
166 	int pull;
167 	u32 ctl_reg;
168 
169 	ctl_reg = lpi_gpio_read(state, pin, LPI_GPIO_CFG_REG);
170 	is_out = ctl_reg & LPI_GPIO_OE_MASK;
171 	pull = FIELD_GET(LPI_GPIO_PULL_MASK, ctl_reg);
172 
173 	switch (param) {
174 	case PIN_CONFIG_BIAS_DISABLE:
175 		if (pull == LPI_GPIO_BIAS_DISABLE)
176 			arg = 1;
177 		break;
178 	case PIN_CONFIG_BIAS_PULL_DOWN:
179 		if (pull == LPI_GPIO_PULL_DOWN)
180 			arg = 1;
181 		break;
182 	case PIN_CONFIG_BIAS_BUS_HOLD:
183 		if (pull == LPI_GPIO_KEEPER)
184 			arg = 1;
185 		break;
186 	case PIN_CONFIG_BIAS_PULL_UP:
187 		if (pull == LPI_GPIO_PULL_UP)
188 			arg = 1;
189 		break;
190 	case PIN_CONFIG_INPUT_ENABLE:
191 	case PIN_CONFIG_LEVEL:
192 		if (is_out)
193 			arg = 1;
194 		break;
195 	default:
196 		return -EINVAL;
197 	}
198 
199 	*config = pinconf_to_config_packed(param, arg);
200 	return 0;
201 }
202 
203 static int lpi_config_set_slew_rate(struct lpi_pinctrl *pctrl,
204 				    const struct lpi_pingroup *g,
205 				    unsigned int group, unsigned int slew)
206 {
207 	unsigned long sval;
208 	void __iomem *reg;
209 	int slew_offset;
210 
211 	if (slew > LPI_SLEW_RATE_MAX) {
212 		dev_err(pctrl->dev, "invalid slew rate %u for pin: %d\n",
213 			slew, group);
214 		return -EINVAL;
215 	}
216 
217 	slew_offset = g->slew_offset;
218 	if (slew_offset == LPI_NO_SLEW)
219 		return 0;
220 
221 	if (pctrl->data->flags & LPI_FLAG_SLEW_RATE_SAME_REG)
222 		reg = pctrl->tlmm_base + LPI_TLMM_REG_OFFSET * group + LPI_GPIO_CFG_REG;
223 	else
224 		reg = pctrl->slew_base + LPI_SLEW_RATE_CTL_REG;
225 
226 	mutex_lock(&pctrl->lock);
227 
228 	sval = ioread32(reg);
229 	sval &= ~(LPI_SLEW_RATE_MASK << slew_offset);
230 	sval |= slew << slew_offset;
231 	iowrite32(sval, reg);
232 
233 	mutex_unlock(&pctrl->lock);
234 
235 	return 0;
236 }
237 
238 static int lpi_config_set(struct pinctrl_dev *pctldev, unsigned int group,
239 			  unsigned long *configs, unsigned int nconfs)
240 {
241 	struct lpi_pinctrl *pctrl = dev_get_drvdata(pctldev->dev);
242 	unsigned int param, arg, pullup = LPI_GPIO_BIAS_DISABLE, strength = 2;
243 	bool value, output_enabled = false;
244 	const struct lpi_pingroup *g;
245 	int i, ret;
246 	u32 val;
247 
248 	g = &pctrl->data->groups[group];
249 	for (i = 0; i < nconfs; i++) {
250 		param = pinconf_to_config_param(configs[i]);
251 		arg = pinconf_to_config_argument(configs[i]);
252 
253 		switch (param) {
254 		case PIN_CONFIG_BIAS_DISABLE:
255 			pullup = LPI_GPIO_BIAS_DISABLE;
256 			break;
257 		case PIN_CONFIG_BIAS_PULL_DOWN:
258 			pullup = LPI_GPIO_PULL_DOWN;
259 			break;
260 		case PIN_CONFIG_BIAS_BUS_HOLD:
261 			pullup = LPI_GPIO_KEEPER;
262 			break;
263 		case PIN_CONFIG_BIAS_PULL_UP:
264 			pullup = LPI_GPIO_PULL_UP;
265 			break;
266 		case PIN_CONFIG_INPUT_ENABLE:
267 			output_enabled = false;
268 			break;
269 		case PIN_CONFIG_LEVEL:
270 			output_enabled = true;
271 			value = arg;
272 			break;
273 		case PIN_CONFIG_DRIVE_STRENGTH:
274 			strength = arg;
275 			break;
276 		case PIN_CONFIG_SLEW_RATE:
277 			ret = lpi_config_set_slew_rate(pctrl, g, group, arg);
278 			if (ret)
279 				return ret;
280 			break;
281 		default:
282 			return -EINVAL;
283 		}
284 	}
285 
286 	/*
287 	 * As per Hardware Programming Guide, when configuring pin as output,
288 	 * set the pin value before setting output-enable (OE).
289 	 */
290 	if (output_enabled) {
291 		val = u32_encode_bits(value ? 1 : 0, LPI_GPIO_VALUE_OUT_MASK);
292 		lpi_gpio_write(pctrl, group, LPI_GPIO_VALUE_REG, val);
293 	}
294 
295 	mutex_lock(&pctrl->lock);
296 	val = lpi_gpio_read(pctrl, group, LPI_GPIO_CFG_REG);
297 
298 	u32p_replace_bits(&val, pullup, LPI_GPIO_PULL_MASK);
299 	u32p_replace_bits(&val, LPI_GPIO_DS_TO_VAL(strength),
300 			  LPI_GPIO_OUT_STRENGTH_MASK);
301 	u32p_replace_bits(&val, output_enabled, LPI_GPIO_OE_MASK);
302 
303 	lpi_gpio_write(pctrl, group, LPI_GPIO_CFG_REG, val);
304 	mutex_unlock(&pctrl->lock);
305 
306 	return 0;
307 }
308 
309 static const struct pinconf_ops lpi_gpio_pinconf_ops = {
310 	.is_generic			= true,
311 	.pin_config_group_get		= lpi_config_get,
312 	.pin_config_group_set		= lpi_config_set,
313 };
314 
315 static int lpi_gpio_direction_input(struct gpio_chip *chip, unsigned int pin)
316 {
317 	struct lpi_pinctrl *state = gpiochip_get_data(chip);
318 	unsigned long config;
319 
320 	config = pinconf_to_config_packed(PIN_CONFIG_INPUT_ENABLE, 1);
321 
322 	return lpi_config_set(state->ctrl, pin, &config, 1);
323 }
324 
325 static int lpi_gpio_direction_output(struct gpio_chip *chip,
326 				     unsigned int pin, int val)
327 {
328 	struct lpi_pinctrl *state = gpiochip_get_data(chip);
329 	unsigned long config;
330 
331 	config = pinconf_to_config_packed(PIN_CONFIG_LEVEL, val);
332 
333 	return lpi_config_set(state->ctrl, pin, &config, 1);
334 }
335 
336 static int lpi_gpio_get(struct gpio_chip *chip, unsigned int pin)
337 {
338 	struct lpi_pinctrl *state = gpiochip_get_data(chip);
339 
340 	return lpi_gpio_read(state, pin, LPI_GPIO_VALUE_REG) &
341 		LPI_GPIO_VALUE_IN_MASK;
342 }
343 
344 static int lpi_gpio_set(struct gpio_chip *chip, unsigned int pin, int value)
345 {
346 	struct lpi_pinctrl *state = gpiochip_get_data(chip);
347 	unsigned long config;
348 
349 	config = pinconf_to_config_packed(PIN_CONFIG_LEVEL, value);
350 
351 	return lpi_config_set(state->ctrl, pin, &config, 1);
352 }
353 
354 #ifdef CONFIG_DEBUG_FS
355 
356 static unsigned int lpi_regval_to_drive(u32 val)
357 {
358 	return (val + 1) * 2;
359 }
360 
361 static void lpi_gpio_dbg_show_one(struct seq_file *s,
362 				  struct pinctrl_dev *pctldev,
363 				  struct gpio_chip *chip,
364 				  unsigned int offset,
365 				  unsigned int gpio)
366 {
367 	struct lpi_pinctrl *state = gpiochip_get_data(chip);
368 	struct pinctrl_pin_desc pindesc;
369 	unsigned int func;
370 	int is_out;
371 	int drive;
372 	int pull;
373 	u32 ctl_reg;
374 
375 	static const char * const pulls[] = {
376 		"no pull",
377 		"pull down",
378 		"keeper",
379 		"pull up"
380 	};
381 
382 	pctldev = pctldev ? : state->ctrl;
383 	pindesc = pctldev->desc->pins[offset];
384 	ctl_reg = lpi_gpio_read(state, offset, LPI_GPIO_CFG_REG);
385 	is_out = ctl_reg & LPI_GPIO_OE_MASK;
386 
387 	func = FIELD_GET(LPI_GPIO_FUNCTION_MASK, ctl_reg);
388 	drive = FIELD_GET(LPI_GPIO_OUT_STRENGTH_MASK, ctl_reg);
389 	pull = FIELD_GET(LPI_GPIO_PULL_MASK, ctl_reg);
390 
391 	seq_printf(s, " %-8s: %-3s %d", pindesc.name, is_out ? "out" : "in", func);
392 	seq_printf(s, " %dmA", lpi_regval_to_drive(drive));
393 	seq_printf(s, " %s", pulls[pull]);
394 }
395 
396 static void lpi_gpio_dbg_show(struct seq_file *s, struct gpio_chip *chip)
397 {
398 	unsigned int gpio = chip->base;
399 	unsigned int i;
400 
401 	for (i = 0; i < chip->ngpio; i++, gpio++) {
402 		lpi_gpio_dbg_show_one(s, NULL, chip, i, gpio);
403 		seq_puts(s, "\n");
404 	}
405 }
406 
407 #else
408 #define lpi_gpio_dbg_show NULL
409 #endif
410 
411 static const struct gpio_chip lpi_gpio_template = {
412 	.direction_input	= lpi_gpio_direction_input,
413 	.direction_output	= lpi_gpio_direction_output,
414 	.get			= lpi_gpio_get,
415 	.set			= lpi_gpio_set,
416 	.request		= gpiochip_generic_request,
417 	.free			= gpiochip_generic_free,
418 	.dbg_show		= lpi_gpio_dbg_show,
419 };
420 
421 static int lpi_build_pin_desc_groups(struct lpi_pinctrl *pctrl)
422 {
423 	int i, ret;
424 
425 	for (i = 0; i < pctrl->data->npins; i++) {
426 		const struct pinctrl_pin_desc *pin_info = pctrl->desc.pins + i;
427 
428 		ret = pinctrl_generic_add_group(pctrl->ctrl, pin_info->name,
429 						  (int *)&pin_info->number, 1, NULL);
430 		if (ret < 0)
431 			goto err_pinctrl;
432 	}
433 
434 	return 0;
435 
436 err_pinctrl:
437 	for (; i > 0; i--)
438 		pinctrl_generic_remove_group(pctrl->ctrl, i - 1);
439 
440 	return ret;
441 }
442 
443 int lpi_pinctrl_probe(struct platform_device *pdev)
444 {
445 	const struct lpi_pinctrl_variant_data *data;
446 	struct device *dev = &pdev->dev;
447 	struct lpi_pinctrl *pctrl;
448 	int ret;
449 
450 	pctrl = devm_kzalloc(dev, sizeof(*pctrl), GFP_KERNEL);
451 	if (!pctrl)
452 		return -ENOMEM;
453 
454 	platform_set_drvdata(pdev, pctrl);
455 
456 	data = of_device_get_match_data(dev);
457 	if (!data)
458 		return -EINVAL;
459 
460 	if (WARN_ON(data->npins > MAX_NR_GPIO))
461 		return -EINVAL;
462 
463 	pctrl->data = data;
464 	pctrl->dev = &pdev->dev;
465 
466 	pctrl->clks[0].id = "core";
467 	pctrl->clks[1].id = "audio";
468 
469 	pctrl->tlmm_base = devm_platform_ioremap_resource(pdev, 0);
470 	if (IS_ERR(pctrl->tlmm_base))
471 		return dev_err_probe(dev, PTR_ERR(pctrl->tlmm_base),
472 				     "TLMM resource not provided\n");
473 
474 	if (!(data->flags & LPI_FLAG_SLEW_RATE_SAME_REG)) {
475 		pctrl->slew_base = devm_platform_ioremap_resource(pdev, 1);
476 		if (IS_ERR(pctrl->slew_base))
477 			return dev_err_probe(dev, PTR_ERR(pctrl->slew_base),
478 					     "Slew resource not provided\n");
479 	}
480 
481 	ret = devm_clk_bulk_get_optional(dev, MAX_LPI_NUM_CLKS, pctrl->clks);
482 	if (ret)
483 		return ret;
484 
485 	ret = clk_bulk_prepare_enable(MAX_LPI_NUM_CLKS, pctrl->clks);
486 	if (ret)
487 		return dev_err_probe(dev, ret, "Can't enable clocks\n");
488 
489 	pctrl->desc.pctlops = &lpi_gpio_pinctrl_ops;
490 	pctrl->desc.pmxops = &lpi_gpio_pinmux_ops;
491 	pctrl->desc.confops = &lpi_gpio_pinconf_ops;
492 	pctrl->desc.owner = THIS_MODULE;
493 	pctrl->desc.name = dev_name(dev);
494 	pctrl->desc.pins = data->pins;
495 	pctrl->desc.npins = data->npins;
496 	pctrl->chip = lpi_gpio_template;
497 	pctrl->chip.parent = dev;
498 	pctrl->chip.base = -1;
499 	pctrl->chip.ngpio = data->npins;
500 	pctrl->chip.label = dev_name(dev);
501 	pctrl->chip.can_sleep = false;
502 
503 	mutex_init(&pctrl->lock);
504 
505 	pctrl->ctrl = devm_pinctrl_register(dev, &pctrl->desc, pctrl);
506 	if (IS_ERR(pctrl->ctrl)) {
507 		ret = PTR_ERR(pctrl->ctrl);
508 		dev_err(dev, "failed to add pin controller\n");
509 		goto err_pinctrl;
510 	}
511 
512 	ret = lpi_build_pin_desc_groups(pctrl);
513 	if (ret)
514 		goto err_pinctrl;
515 
516 	ret = devm_gpiochip_add_data(dev, &pctrl->chip, pctrl);
517 	if (ret) {
518 		dev_err(pctrl->dev, "can't add gpio chip\n");
519 		goto err_pinctrl;
520 	}
521 
522 	return 0;
523 
524 err_pinctrl:
525 	mutex_destroy(&pctrl->lock);
526 	clk_bulk_disable_unprepare(MAX_LPI_NUM_CLKS, pctrl->clks);
527 
528 	return ret;
529 }
530 EXPORT_SYMBOL_GPL(lpi_pinctrl_probe);
531 
532 void lpi_pinctrl_remove(struct platform_device *pdev)
533 {
534 	struct lpi_pinctrl *pctrl = platform_get_drvdata(pdev);
535 	int i;
536 
537 	mutex_destroy(&pctrl->lock);
538 	clk_bulk_disable_unprepare(MAX_LPI_NUM_CLKS, pctrl->clks);
539 
540 	for (i = 0; i < pctrl->data->npins; i++)
541 		pinctrl_generic_remove_group(pctrl->ctrl, i);
542 }
543 EXPORT_SYMBOL_GPL(lpi_pinctrl_remove);
544 
545 MODULE_DESCRIPTION("QTI LPI GPIO pin control driver");
546 MODULE_LICENSE("GPL");
547