xref: /linux/drivers/pinctrl/qcom/pinctrl-lpass-lpi.c (revision 4c630f307455c06f99bdeca7f7a1ab5318604fe0)
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_device.h>
12 #include <linux/seq_file.h>
13 
14 #include <linux/pinctrl/pinconf-generic.h>
15 #include <linux/pinctrl/pinconf.h>
16 #include <linux/pinctrl/pinmux.h>
17 
18 #include "../pinctrl-utils.h"
19 
20 #include "pinctrl-lpass-lpi.h"
21 
22 #define MAX_NR_GPIO		23
23 #define GPIO_FUNC		0
24 #define MAX_LPI_NUM_CLKS	2
25 
26 struct lpi_pinctrl {
27 	struct device *dev;
28 	struct pinctrl_dev *ctrl;
29 	struct gpio_chip chip;
30 	struct pinctrl_desc desc;
31 	char __iomem *tlmm_base;
32 	char __iomem *slew_base;
33 	struct clk_bulk_data clks[MAX_LPI_NUM_CLKS];
34 	struct mutex slew_access_lock;
35 	DECLARE_BITMAP(ever_gpio, MAX_NR_GPIO);
36 	const struct lpi_pinctrl_variant_data *data;
37 };
38 
39 static int lpi_gpio_read(struct lpi_pinctrl *state, unsigned int pin,
40 			 unsigned int addr)
41 {
42 	return ioread32(state->tlmm_base + LPI_TLMM_REG_OFFSET * pin + addr);
43 }
44 
45 static int lpi_gpio_write(struct lpi_pinctrl *state, unsigned int pin,
46 			  unsigned int addr, unsigned int val)
47 {
48 	iowrite32(val, state->tlmm_base + LPI_TLMM_REG_OFFSET * pin + addr);
49 
50 	return 0;
51 }
52 
53 static const struct pinctrl_ops lpi_gpio_pinctrl_ops = {
54 	.get_groups_count	= pinctrl_generic_get_group_count,
55 	.get_group_name		= pinctrl_generic_get_group_name,
56 	.get_group_pins		= pinctrl_generic_get_group_pins,
57 	.dt_node_to_map		= pinconf_generic_dt_node_to_map_group,
58 	.dt_free_map		= pinctrl_utils_free_map,
59 };
60 
61 static int lpi_gpio_get_functions_count(struct pinctrl_dev *pctldev)
62 {
63 	struct lpi_pinctrl *pctrl = pinctrl_dev_get_drvdata(pctldev);
64 
65 	return pctrl->data->nfunctions;
66 }
67 
68 static const char *lpi_gpio_get_function_name(struct pinctrl_dev *pctldev,
69 					      unsigned int function)
70 {
71 	struct lpi_pinctrl *pctrl = pinctrl_dev_get_drvdata(pctldev);
72 
73 	return pctrl->data->functions[function].name;
74 }
75 
76 static int lpi_gpio_get_function_groups(struct pinctrl_dev *pctldev,
77 					unsigned int function,
78 					const char *const **groups,
79 					unsigned *const num_qgroups)
80 {
81 	struct lpi_pinctrl *pctrl = pinctrl_dev_get_drvdata(pctldev);
82 
83 	*groups = pctrl->data->functions[function].groups;
84 	*num_qgroups = pctrl->data->functions[function].ngroups;
85 
86 	return 0;
87 }
88 
89 static int lpi_gpio_set_mux(struct pinctrl_dev *pctldev, unsigned int function,
90 			    unsigned int group)
91 {
92 	struct lpi_pinctrl *pctrl = pinctrl_dev_get_drvdata(pctldev);
93 	const struct lpi_pingroup *g = &pctrl->data->groups[group];
94 	u32 val;
95 	int i, pin = g->pin;
96 
97 	for (i = 0; i < g->nfuncs; i++) {
98 		if (g->funcs[i] == function)
99 			break;
100 	}
101 
102 	if (WARN_ON(i == g->nfuncs))
103 		return -EINVAL;
104 
105 	val = lpi_gpio_read(pctrl, pin, LPI_GPIO_CFG_REG);
106 
107 	/*
108 	 * If this is the first time muxing to GPIO and the direction is
109 	 * output, make sure that we're not going to be glitching the pin
110 	 * by reading the current state of the pin and setting it as the
111 	 * output.
112 	 */
113 	if (i == GPIO_FUNC && (val & LPI_GPIO_OE_MASK) &&
114 	    !test_and_set_bit(group, pctrl->ever_gpio)) {
115 		u32 io_val = lpi_gpio_read(pctrl, group, LPI_GPIO_VALUE_REG);
116 
117 		if (io_val & LPI_GPIO_VALUE_IN_MASK) {
118 			if (!(io_val & LPI_GPIO_VALUE_OUT_MASK))
119 				lpi_gpio_write(pctrl, group, LPI_GPIO_VALUE_REG,
120 					       io_val | LPI_GPIO_VALUE_OUT_MASK);
121 		} else {
122 			if (io_val & LPI_GPIO_VALUE_OUT_MASK)
123 				lpi_gpio_write(pctrl, group, LPI_GPIO_VALUE_REG,
124 					       io_val & ~LPI_GPIO_VALUE_OUT_MASK);
125 		}
126 	}
127 
128 	u32p_replace_bits(&val, i, LPI_GPIO_FUNCTION_MASK);
129 	lpi_gpio_write(pctrl, pin, LPI_GPIO_CFG_REG, val);
130 
131 	return 0;
132 }
133 
134 static const struct pinmux_ops lpi_gpio_pinmux_ops = {
135 	.get_functions_count	= lpi_gpio_get_functions_count,
136 	.get_function_name	= lpi_gpio_get_function_name,
137 	.get_function_groups	= lpi_gpio_get_function_groups,
138 	.set_mux		= lpi_gpio_set_mux,
139 };
140 
141 static int lpi_config_get(struct pinctrl_dev *pctldev,
142 			  unsigned int pin, unsigned long *config)
143 {
144 	unsigned int param = pinconf_to_config_param(*config);
145 	struct lpi_pinctrl *state = dev_get_drvdata(pctldev->dev);
146 	unsigned int arg = 0;
147 	int is_out;
148 	int pull;
149 	u32 ctl_reg;
150 
151 	ctl_reg = lpi_gpio_read(state, pin, LPI_GPIO_CFG_REG);
152 	is_out = ctl_reg & LPI_GPIO_OE_MASK;
153 	pull = FIELD_GET(LPI_GPIO_PULL_MASK, ctl_reg);
154 
155 	switch (param) {
156 	case PIN_CONFIG_BIAS_DISABLE:
157 		if (pull == LPI_GPIO_BIAS_DISABLE)
158 			arg = 1;
159 		break;
160 	case PIN_CONFIG_BIAS_PULL_DOWN:
161 		if (pull == LPI_GPIO_PULL_DOWN)
162 			arg = 1;
163 		break;
164 	case PIN_CONFIG_BIAS_BUS_HOLD:
165 		if (pull == LPI_GPIO_KEEPER)
166 			arg = 1;
167 		break;
168 	case PIN_CONFIG_BIAS_PULL_UP:
169 		if (pull == LPI_GPIO_PULL_UP)
170 			arg = 1;
171 		break;
172 	case PIN_CONFIG_INPUT_ENABLE:
173 	case PIN_CONFIG_OUTPUT:
174 		if (is_out)
175 			arg = 1;
176 		break;
177 	default:
178 		return -EINVAL;
179 	}
180 
181 	*config = pinconf_to_config_packed(param, arg);
182 	return 0;
183 }
184 
185 static int lpi_config_set(struct pinctrl_dev *pctldev, unsigned int group,
186 			  unsigned long *configs, unsigned int nconfs)
187 {
188 	struct lpi_pinctrl *pctrl = dev_get_drvdata(pctldev->dev);
189 	unsigned int param, arg, pullup = LPI_GPIO_BIAS_DISABLE, strength = 2;
190 	bool value, output_enabled = false;
191 	const struct lpi_pingroup *g;
192 	unsigned long sval;
193 	int i, slew_offset;
194 	u32 val;
195 
196 	g = &pctrl->data->groups[group];
197 	for (i = 0; i < nconfs; i++) {
198 		param = pinconf_to_config_param(configs[i]);
199 		arg = pinconf_to_config_argument(configs[i]);
200 
201 		switch (param) {
202 		case PIN_CONFIG_BIAS_DISABLE:
203 			pullup = LPI_GPIO_BIAS_DISABLE;
204 			break;
205 		case PIN_CONFIG_BIAS_PULL_DOWN:
206 			pullup = LPI_GPIO_PULL_DOWN;
207 			break;
208 		case PIN_CONFIG_BIAS_BUS_HOLD:
209 			pullup = LPI_GPIO_KEEPER;
210 			break;
211 		case PIN_CONFIG_BIAS_PULL_UP:
212 			pullup = LPI_GPIO_PULL_UP;
213 			break;
214 		case PIN_CONFIG_INPUT_ENABLE:
215 			output_enabled = false;
216 			break;
217 		case PIN_CONFIG_OUTPUT:
218 			output_enabled = true;
219 			value = arg;
220 			break;
221 		case PIN_CONFIG_DRIVE_STRENGTH:
222 			strength = arg;
223 			break;
224 		case PIN_CONFIG_SLEW_RATE:
225 			if (arg > LPI_SLEW_RATE_MAX) {
226 				dev_err(pctldev->dev, "invalid slew rate %u for pin: %d\n",
227 					arg, group);
228 				return -EINVAL;
229 			}
230 
231 			slew_offset = g->slew_offset;
232 			if (slew_offset == LPI_NO_SLEW)
233 				break;
234 
235 			mutex_lock(&pctrl->slew_access_lock);
236 
237 			sval = ioread32(pctrl->slew_base + LPI_SLEW_RATE_CTL_REG);
238 			sval &= ~(LPI_SLEW_RATE_MASK << slew_offset);
239 			sval |= arg << slew_offset;
240 			iowrite32(sval, pctrl->slew_base + LPI_SLEW_RATE_CTL_REG);
241 
242 			mutex_unlock(&pctrl->slew_access_lock);
243 			break;
244 		default:
245 			return -EINVAL;
246 		}
247 	}
248 
249 	/*
250 	 * As per Hardware Programming Guide, when configuring pin as output,
251 	 * set the pin value before setting output-enable (OE).
252 	 */
253 	if (output_enabled) {
254 		val = u32_encode_bits(value ? 1 : 0, LPI_GPIO_VALUE_OUT_MASK);
255 		lpi_gpio_write(pctrl, group, LPI_GPIO_VALUE_REG, val);
256 	}
257 
258 	val = lpi_gpio_read(pctrl, group, LPI_GPIO_CFG_REG);
259 
260 	u32p_replace_bits(&val, pullup, LPI_GPIO_PULL_MASK);
261 	u32p_replace_bits(&val, LPI_GPIO_DS_TO_VAL(strength),
262 			  LPI_GPIO_OUT_STRENGTH_MASK);
263 	u32p_replace_bits(&val, output_enabled, LPI_GPIO_OE_MASK);
264 
265 	lpi_gpio_write(pctrl, group, LPI_GPIO_CFG_REG, val);
266 
267 	return 0;
268 }
269 
270 static const struct pinconf_ops lpi_gpio_pinconf_ops = {
271 	.is_generic			= true,
272 	.pin_config_group_get		= lpi_config_get,
273 	.pin_config_group_set		= lpi_config_set,
274 };
275 
276 static int lpi_gpio_direction_input(struct gpio_chip *chip, unsigned int pin)
277 {
278 	struct lpi_pinctrl *state = gpiochip_get_data(chip);
279 	unsigned long config;
280 
281 	config = pinconf_to_config_packed(PIN_CONFIG_INPUT_ENABLE, 1);
282 
283 	return lpi_config_set(state->ctrl, pin, &config, 1);
284 }
285 
286 static int lpi_gpio_direction_output(struct gpio_chip *chip,
287 				     unsigned int pin, int val)
288 {
289 	struct lpi_pinctrl *state = gpiochip_get_data(chip);
290 	unsigned long config;
291 
292 	config = pinconf_to_config_packed(PIN_CONFIG_OUTPUT, val);
293 
294 	return lpi_config_set(state->ctrl, pin, &config, 1);
295 }
296 
297 static int lpi_gpio_get(struct gpio_chip *chip, unsigned int pin)
298 {
299 	struct lpi_pinctrl *state = gpiochip_get_data(chip);
300 
301 	return lpi_gpio_read(state, pin, LPI_GPIO_VALUE_REG) &
302 		LPI_GPIO_VALUE_IN_MASK;
303 }
304 
305 static void lpi_gpio_set(struct gpio_chip *chip, unsigned int pin, int value)
306 {
307 	struct lpi_pinctrl *state = gpiochip_get_data(chip);
308 	unsigned long config;
309 
310 	config = pinconf_to_config_packed(PIN_CONFIG_OUTPUT, value);
311 
312 	lpi_config_set(state->ctrl, pin, &config, 1);
313 }
314 
315 #ifdef CONFIG_DEBUG_FS
316 #include <linux/seq_file.h>
317 
318 static unsigned int lpi_regval_to_drive(u32 val)
319 {
320 	return (val + 1) * 2;
321 }
322 
323 static void lpi_gpio_dbg_show_one(struct seq_file *s,
324 				  struct pinctrl_dev *pctldev,
325 				  struct gpio_chip *chip,
326 				  unsigned int offset,
327 				  unsigned int gpio)
328 {
329 	struct lpi_pinctrl *state = gpiochip_get_data(chip);
330 	struct pinctrl_pin_desc pindesc;
331 	unsigned int func;
332 	int is_out;
333 	int drive;
334 	int pull;
335 	u32 ctl_reg;
336 
337 	static const char * const pulls[] = {
338 		"no pull",
339 		"pull down",
340 		"keeper",
341 		"pull up"
342 	};
343 
344 	pctldev = pctldev ? : state->ctrl;
345 	pindesc = pctldev->desc->pins[offset];
346 	ctl_reg = lpi_gpio_read(state, offset, LPI_GPIO_CFG_REG);
347 	is_out = ctl_reg & LPI_GPIO_OE_MASK;
348 
349 	func = FIELD_GET(LPI_GPIO_FUNCTION_MASK, ctl_reg);
350 	drive = FIELD_GET(LPI_GPIO_OUT_STRENGTH_MASK, ctl_reg);
351 	pull = FIELD_GET(LPI_GPIO_PULL_MASK, ctl_reg);
352 
353 	seq_printf(s, " %-8s: %-3s %d", pindesc.name, is_out ? "out" : "in", func);
354 	seq_printf(s, " %dmA", lpi_regval_to_drive(drive));
355 	seq_printf(s, " %s", pulls[pull]);
356 }
357 
358 static void lpi_gpio_dbg_show(struct seq_file *s, struct gpio_chip *chip)
359 {
360 	unsigned int gpio = chip->base;
361 	unsigned int i;
362 
363 	for (i = 0; i < chip->ngpio; i++, gpio++) {
364 		lpi_gpio_dbg_show_one(s, NULL, chip, i, gpio);
365 		seq_puts(s, "\n");
366 	}
367 }
368 
369 #else
370 #define lpi_gpio_dbg_show NULL
371 #endif
372 
373 static const struct gpio_chip lpi_gpio_template = {
374 	.direction_input	= lpi_gpio_direction_input,
375 	.direction_output	= lpi_gpio_direction_output,
376 	.get			= lpi_gpio_get,
377 	.set			= lpi_gpio_set,
378 	.request		= gpiochip_generic_request,
379 	.free			= gpiochip_generic_free,
380 	.dbg_show		= lpi_gpio_dbg_show,
381 };
382 
383 static int lpi_build_pin_desc_groups(struct lpi_pinctrl *pctrl)
384 {
385 	int i, ret;
386 
387 	for (i = 0; i < pctrl->data->npins; i++) {
388 		const struct pinctrl_pin_desc *pin_info = pctrl->desc.pins + i;
389 
390 		ret = pinctrl_generic_add_group(pctrl->ctrl, pin_info->name,
391 						  (int *)&pin_info->number, 1, NULL);
392 		if (ret < 0)
393 			goto err_pinctrl;
394 	}
395 
396 	return 0;
397 
398 err_pinctrl:
399 	for (; i > 0; i--)
400 		pinctrl_generic_remove_group(pctrl->ctrl, i - 1);
401 
402 	return ret;
403 }
404 
405 int lpi_pinctrl_probe(struct platform_device *pdev)
406 {
407 	const struct lpi_pinctrl_variant_data *data;
408 	struct device *dev = &pdev->dev;
409 	struct lpi_pinctrl *pctrl;
410 	int ret;
411 
412 	pctrl = devm_kzalloc(dev, sizeof(*pctrl), GFP_KERNEL);
413 	if (!pctrl)
414 		return -ENOMEM;
415 
416 	platform_set_drvdata(pdev, pctrl);
417 
418 	data = of_device_get_match_data(dev);
419 	if (!data)
420 		return -EINVAL;
421 
422 	if (WARN_ON(data->npins > MAX_NR_GPIO))
423 		return -EINVAL;
424 
425 	pctrl->data = data;
426 	pctrl->dev = &pdev->dev;
427 
428 	pctrl->clks[0].id = "core";
429 	pctrl->clks[1].id = "audio";
430 
431 	pctrl->tlmm_base = devm_platform_ioremap_resource(pdev, 0);
432 	if (IS_ERR(pctrl->tlmm_base))
433 		return dev_err_probe(dev, PTR_ERR(pctrl->tlmm_base),
434 				     "TLMM resource not provided\n");
435 
436 	pctrl->slew_base = devm_platform_ioremap_resource(pdev, 1);
437 	if (IS_ERR(pctrl->slew_base))
438 		return dev_err_probe(dev, PTR_ERR(pctrl->slew_base),
439 				     "Slew resource not provided\n");
440 
441 	if (of_property_read_bool(dev->of_node, "qcom,adsp-bypass-mode"))
442 		ret = devm_clk_bulk_get_optional(dev, MAX_LPI_NUM_CLKS, pctrl->clks);
443 	else
444 		ret = devm_clk_bulk_get(dev, MAX_LPI_NUM_CLKS, pctrl->clks);
445 
446 	if (ret)
447 		return ret;
448 
449 	ret = clk_bulk_prepare_enable(MAX_LPI_NUM_CLKS, pctrl->clks);
450 	if (ret)
451 		return dev_err_probe(dev, ret, "Can't enable clocks\n");
452 
453 	pctrl->desc.pctlops = &lpi_gpio_pinctrl_ops;
454 	pctrl->desc.pmxops = &lpi_gpio_pinmux_ops;
455 	pctrl->desc.confops = &lpi_gpio_pinconf_ops;
456 	pctrl->desc.owner = THIS_MODULE;
457 	pctrl->desc.name = dev_name(dev);
458 	pctrl->desc.pins = data->pins;
459 	pctrl->desc.npins = data->npins;
460 	pctrl->chip = lpi_gpio_template;
461 	pctrl->chip.parent = dev;
462 	pctrl->chip.base = -1;
463 	pctrl->chip.ngpio = data->npins;
464 	pctrl->chip.label = dev_name(dev);
465 	pctrl->chip.can_sleep = false;
466 
467 	mutex_init(&pctrl->slew_access_lock);
468 
469 	pctrl->ctrl = devm_pinctrl_register(dev, &pctrl->desc, pctrl);
470 	if (IS_ERR(pctrl->ctrl)) {
471 		ret = PTR_ERR(pctrl->ctrl);
472 		dev_err(dev, "failed to add pin controller\n");
473 		goto err_pinctrl;
474 	}
475 
476 	ret = lpi_build_pin_desc_groups(pctrl);
477 	if (ret)
478 		goto err_pinctrl;
479 
480 	ret = devm_gpiochip_add_data(dev, &pctrl->chip, pctrl);
481 	if (ret) {
482 		dev_err(pctrl->dev, "can't add gpio chip\n");
483 		goto err_pinctrl;
484 	}
485 
486 	return 0;
487 
488 err_pinctrl:
489 	mutex_destroy(&pctrl->slew_access_lock);
490 	clk_bulk_disable_unprepare(MAX_LPI_NUM_CLKS, pctrl->clks);
491 
492 	return ret;
493 }
494 EXPORT_SYMBOL_GPL(lpi_pinctrl_probe);
495 
496 int lpi_pinctrl_remove(struct platform_device *pdev)
497 {
498 	struct lpi_pinctrl *pctrl = platform_get_drvdata(pdev);
499 	int i;
500 
501 	mutex_destroy(&pctrl->slew_access_lock);
502 	clk_bulk_disable_unprepare(MAX_LPI_NUM_CLKS, pctrl->clks);
503 
504 	for (i = 0; i < pctrl->data->npins; i++)
505 		pinctrl_generic_remove_group(pctrl->ctrl, i);
506 
507 	return 0;
508 }
509 EXPORT_SYMBOL_GPL(lpi_pinctrl_remove);
510 
511 MODULE_DESCRIPTION("QTI LPI GPIO pin control driver");
512 MODULE_LICENSE("GPL");
513