xref: /linux/drivers/pinctrl/renesas/gpio.c (revision b4ada0618eed0fbd1b1630f73deb048c592b06a1)
1 // SPDX-License-Identifier: GPL-2.0
2 /*
3  * SuperH Pin Function Controller GPIO driver.
4  *
5  * Copyright (C) 2008 Magnus Damm
6  * Copyright (C) 2009 - 2012 Paul Mundt
7  */
8 
9 #include <linux/device.h>
10 #include <linux/gpio/driver.h>
11 #include <linux/module.h>
12 #include <linux/pinctrl/consumer.h>
13 #include <linux/slab.h>
14 #include <linux/spinlock.h>
15 
16 #include "core.h"
17 
18 struct sh_pfc_gpio_data_reg {
19 	const struct pinmux_data_reg *info;
20 	u32 shadow;
21 };
22 
23 struct sh_pfc_gpio_pin {
24 	u8 dbit;
25 	u8 dreg;
26 };
27 
28 struct sh_pfc_chip {
29 	struct sh_pfc			*pfc;
30 	struct gpio_chip		gpio_chip;
31 
32 	struct sh_pfc_window		*mem;
33 	struct sh_pfc_gpio_data_reg	*regs;
34 	struct sh_pfc_gpio_pin		*pins;
35 };
36 
37 static struct sh_pfc *gpio_to_pfc(struct gpio_chip *gc)
38 {
39 	struct sh_pfc_chip *chip = gpiochip_get_data(gc);
40 	return chip->pfc;
41 }
42 
43 static void gpio_get_data_reg(struct sh_pfc_chip *chip, unsigned int offset,
44 			      struct sh_pfc_gpio_data_reg **reg,
45 			      unsigned int *bit)
46 {
47 	int idx = sh_pfc_get_pin_index(chip->pfc, offset);
48 	struct sh_pfc_gpio_pin *gpio_pin = &chip->pins[idx];
49 
50 	*reg = &chip->regs[gpio_pin->dreg];
51 	*bit = gpio_pin->dbit;
52 }
53 
54 static u32 gpio_read_data_reg(struct sh_pfc_chip *chip,
55 			      const struct pinmux_data_reg *dreg)
56 {
57 	phys_addr_t address = dreg->reg;
58 	void __iomem *mem = address - chip->mem->phys + chip->mem->virt;
59 
60 	return sh_pfc_read_raw_reg(mem, dreg->reg_width);
61 }
62 
63 static void gpio_write_data_reg(struct sh_pfc_chip *chip,
64 				const struct pinmux_data_reg *dreg, u32 value)
65 {
66 	phys_addr_t address = dreg->reg;
67 	void __iomem *mem = address - chip->mem->phys + chip->mem->virt;
68 
69 	sh_pfc_write_raw_reg(mem, dreg->reg_width, value);
70 }
71 
72 static void gpio_setup_data_reg(struct sh_pfc_chip *chip, unsigned idx)
73 {
74 	struct sh_pfc *pfc = chip->pfc;
75 	struct sh_pfc_gpio_pin *gpio_pin = &chip->pins[idx];
76 	const struct sh_pfc_pin *pin = &pfc->info->pins[idx];
77 	const struct pinmux_data_reg *dreg;
78 	unsigned int bit;
79 	unsigned int i;
80 
81 	for (i = 0, dreg = pfc->info->data_regs; dreg->reg_width; ++i, ++dreg) {
82 		for (bit = 0; bit < dreg->reg_width; bit++) {
83 			if (dreg->enum_ids[bit] == pin->enum_id) {
84 				gpio_pin->dreg = i;
85 				gpio_pin->dbit = bit;
86 				return;
87 			}
88 		}
89 	}
90 
91 	BUG();
92 }
93 
94 static int gpio_setup_data_regs(struct sh_pfc_chip *chip)
95 {
96 	struct sh_pfc *pfc = chip->pfc;
97 	const struct pinmux_data_reg *dreg;
98 	unsigned int i;
99 
100 	/* Count the number of data registers, allocate memory and initialize
101 	 * them.
102 	 */
103 	for (i = 0; pfc->info->data_regs[i].reg_width; ++i)
104 		;
105 
106 	chip->regs = devm_kcalloc(pfc->dev, i, sizeof(*chip->regs),
107 				  GFP_KERNEL);
108 	if (chip->regs == NULL)
109 		return -ENOMEM;
110 
111 	for (i = 0, dreg = pfc->info->data_regs; dreg->reg_width; ++i, ++dreg) {
112 		chip->regs[i].info = dreg;
113 		chip->regs[i].shadow = gpio_read_data_reg(chip, dreg);
114 	}
115 
116 	for (i = 0; i < pfc->info->nr_pins; i++) {
117 		if (pfc->info->pins[i].enum_id == 0)
118 			continue;
119 
120 		gpio_setup_data_reg(chip, i);
121 	}
122 
123 	return 0;
124 }
125 
126 /* -----------------------------------------------------------------------------
127  * Pin GPIOs
128  */
129 
130 static int gpio_pin_request(struct gpio_chip *gc, unsigned offset)
131 {
132 	struct sh_pfc *pfc = gpio_to_pfc(gc);
133 	int idx = sh_pfc_get_pin_index(pfc, offset);
134 
135 	if (idx < 0 || pfc->info->pins[idx].enum_id == 0)
136 		return -EINVAL;
137 
138 	return pinctrl_gpio_request(gc, offset);
139 }
140 
141 static void gpio_pin_free(struct gpio_chip *gc, unsigned offset)
142 {
143 	return pinctrl_gpio_free(gc, offset);
144 }
145 
146 static void gpio_pin_set_value(struct sh_pfc_chip *chip, unsigned offset,
147 			       int value)
148 {
149 	struct sh_pfc_gpio_data_reg *reg;
150 	unsigned int bit;
151 	unsigned int pos;
152 
153 	gpio_get_data_reg(chip, offset, &reg, &bit);
154 
155 	pos = reg->info->reg_width - (bit + 1);
156 
157 	if (value)
158 		reg->shadow |= BIT(pos);
159 	else
160 		reg->shadow &= ~BIT(pos);
161 
162 	gpio_write_data_reg(chip, reg->info, reg->shadow);
163 }
164 
165 static int gpio_pin_direction_input(struct gpio_chip *gc, unsigned offset)
166 {
167 	return pinctrl_gpio_direction_input(gc, offset);
168 }
169 
170 static int gpio_pin_direction_output(struct gpio_chip *gc, unsigned offset,
171 				    int value)
172 {
173 	gpio_pin_set_value(gpiochip_get_data(gc), offset, value);
174 
175 	return pinctrl_gpio_direction_output(gc, offset);
176 }
177 
178 static int gpio_pin_get(struct gpio_chip *gc, unsigned offset)
179 {
180 	struct sh_pfc_chip *chip = gpiochip_get_data(gc);
181 	struct sh_pfc_gpio_data_reg *reg;
182 	unsigned int bit;
183 	unsigned int pos;
184 
185 	gpio_get_data_reg(chip, offset, &reg, &bit);
186 
187 	pos = reg->info->reg_width - (bit + 1);
188 
189 	return (gpio_read_data_reg(chip, reg->info) >> pos) & 1;
190 }
191 
192 static int gpio_pin_set(struct gpio_chip *gc, unsigned int offset, int value)
193 {
194 	gpio_pin_set_value(gpiochip_get_data(gc), offset, value);
195 
196 	return 0;
197 }
198 
199 static int gpio_pin_to_irq(struct gpio_chip *gc, unsigned offset)
200 {
201 	struct sh_pfc *pfc = gpio_to_pfc(gc);
202 	unsigned int i, k;
203 
204 	for (i = 0; i < pfc->info->gpio_irq_size; i++) {
205 		const short *gpios = pfc->info->gpio_irq[i].gpios;
206 
207 		for (k = 0; gpios[k] >= 0; k++) {
208 			if (gpios[k] == offset)
209 				return pfc->irqs[i];
210 		}
211 	}
212 
213 	return 0;
214 }
215 
216 static int gpio_pin_setup(struct sh_pfc_chip *chip)
217 {
218 	struct sh_pfc *pfc = chip->pfc;
219 	struct gpio_chip *gc = &chip->gpio_chip;
220 	int ret;
221 
222 	chip->pins = devm_kcalloc(pfc->dev,
223 				  pfc->info->nr_pins, sizeof(*chip->pins),
224 				  GFP_KERNEL);
225 	if (chip->pins == NULL)
226 		return -ENOMEM;
227 
228 	ret = gpio_setup_data_regs(chip);
229 	if (ret < 0)
230 		return ret;
231 
232 	gc->request = gpio_pin_request;
233 	gc->free = gpio_pin_free;
234 	gc->direction_input = gpio_pin_direction_input;
235 	gc->get = gpio_pin_get;
236 	gc->direction_output = gpio_pin_direction_output;
237 	gc->set = gpio_pin_set;
238 	gc->to_irq = gpio_pin_to_irq;
239 
240 	gc->label = pfc->info->name;
241 	gc->parent = pfc->dev;
242 	gc->owner = THIS_MODULE;
243 	gc->base = IS_ENABLED(CONFIG_PINCTRL_SH_FUNC_GPIO) ? 0 : -1;
244 	gc->ngpio = pfc->nr_gpio_pins;
245 
246 	return 0;
247 }
248 
249 /* -----------------------------------------------------------------------------
250  * Function GPIOs
251  */
252 
253 #ifdef CONFIG_PINCTRL_SH_FUNC_GPIO
254 static int gpio_function_request(struct gpio_chip *gc, unsigned offset)
255 {
256 	struct sh_pfc *pfc = gpio_to_pfc(gc);
257 	unsigned int mark = pfc->info->func_gpios[offset].enum_id;
258 	unsigned long flags;
259 	int ret;
260 
261 	dev_notice_once(pfc->dev,
262 			"Use of GPIO API for function requests is deprecated, convert to pinctrl\n");
263 
264 	if (mark == 0)
265 		return -EINVAL;
266 
267 	spin_lock_irqsave(&pfc->lock, flags);
268 	ret = sh_pfc_config_mux(pfc, mark, PINMUX_TYPE_FUNCTION);
269 	spin_unlock_irqrestore(&pfc->lock, flags);
270 
271 	return ret;
272 }
273 
274 static int gpio_function_setup(struct sh_pfc_chip *chip)
275 {
276 	struct sh_pfc *pfc = chip->pfc;
277 	struct gpio_chip *gc = &chip->gpio_chip;
278 
279 	gc->request = gpio_function_request;
280 
281 	gc->label = pfc->info->name;
282 	gc->owner = THIS_MODULE;
283 	gc->base = pfc->nr_gpio_pins;
284 	gc->ngpio = pfc->info->nr_func_gpios;
285 
286 	return 0;
287 }
288 #endif /* CONFIG_PINCTRL_SH_FUNC_GPIO */
289 
290 /* -----------------------------------------------------------------------------
291  * Register/unregister
292  */
293 
294 static struct sh_pfc_chip *
295 sh_pfc_add_gpiochip(struct sh_pfc *pfc, int(*setup)(struct sh_pfc_chip *),
296 		    struct sh_pfc_window *mem)
297 {
298 	struct sh_pfc_chip *chip;
299 	int ret;
300 
301 	chip = devm_kzalloc(pfc->dev, sizeof(*chip), GFP_KERNEL);
302 	if (unlikely(!chip))
303 		return ERR_PTR(-ENOMEM);
304 
305 	chip->mem = mem;
306 	chip->pfc = pfc;
307 
308 	ret = setup(chip);
309 	if (ret < 0)
310 		return ERR_PTR(ret);
311 
312 	ret = devm_gpiochip_add_data(pfc->dev, &chip->gpio_chip, chip);
313 	if (unlikely(ret < 0))
314 		return ERR_PTR(ret);
315 
316 	dev_info(pfc->dev, "%s handling gpio %u -> %u\n",
317 		 chip->gpio_chip.label, chip->gpio_chip.base,
318 		 chip->gpio_chip.base + chip->gpio_chip.ngpio - 1);
319 
320 	return chip;
321 }
322 
323 int sh_pfc_register_gpiochip(struct sh_pfc *pfc)
324 {
325 	struct sh_pfc_chip *chip;
326 	phys_addr_t address;
327 	unsigned int i;
328 
329 	if (pfc->info->data_regs == NULL)
330 		return 0;
331 
332 	/* Find the memory window that contains the GPIO registers. Boards that
333 	 * register a separate GPIO device will not supply a memory resource
334 	 * that covers the data registers. In that case don't try to handle
335 	 * GPIOs.
336 	 */
337 	address = pfc->info->data_regs[0].reg;
338 	for (i = 0; i < pfc->num_windows; ++i) {
339 		struct sh_pfc_window *window = &pfc->windows[i];
340 
341 		if (address >= window->phys &&
342 		    address < window->phys + window->size)
343 			break;
344 	}
345 
346 	if (i == pfc->num_windows)
347 		return 0;
348 
349 	/* If we have IRQ resources make sure their number is correct. */
350 	if (pfc->num_irqs != pfc->info->gpio_irq_size) {
351 		dev_err(pfc->dev, "invalid number of IRQ resources\n");
352 		return -EINVAL;
353 	}
354 
355 	/* Register the real GPIOs chip. */
356 	chip = sh_pfc_add_gpiochip(pfc, gpio_pin_setup, &pfc->windows[i]);
357 	if (IS_ERR(chip))
358 		return PTR_ERR(chip);
359 
360 	pfc->gpio = chip;
361 
362 	if (IS_ENABLED(CONFIG_OF) && pfc->dev->of_node)
363 		return 0;
364 
365 #ifdef CONFIG_PINCTRL_SH_FUNC_GPIO
366 	/*
367 	 * Register the GPIO to pin mappings. As pins with GPIO ports
368 	 * must come first in the ranges, skip the pins without GPIO
369 	 * ports by stopping at the first range that contains such a
370 	 * pin.
371 	 */
372 	for (i = 0; i < pfc->nr_ranges; ++i) {
373 		const struct sh_pfc_pin_range *range = &pfc->ranges[i];
374 		int ret;
375 
376 		if (range->start >= pfc->nr_gpio_pins)
377 			break;
378 
379 		ret = gpiochip_add_pin_range(&chip->gpio_chip,
380 			dev_name(pfc->dev), range->start, range->start,
381 			range->end - range->start + 1);
382 		if (ret < 0)
383 			return ret;
384 	}
385 
386 	/* Register the function GPIOs chip. */
387 	if (pfc->info->nr_func_gpios) {
388 		chip = sh_pfc_add_gpiochip(pfc, gpio_function_setup, NULL);
389 		if (IS_ERR(chip))
390 			return PTR_ERR(chip);
391 	}
392 #endif /* CONFIG_PINCTRL_SH_FUNC_GPIO */
393 
394 	return 0;
395 }
396