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