xref: /openbmc/linux/drivers/pinctrl/renesas/gpio.c (revision e15a5365)
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/init.h>
12 #include <linux/module.h>
13 #include <linux/pinctrl/consumer.h>
14 #include <linux/slab.h>
15 #include <linux/spinlock.h>
16 
17 #include "core.h"
18 
19 struct sh_pfc_gpio_data_reg {
20 	const struct pinmux_data_reg *info;
21 	u32 shadow;
22 };
23 
24 struct sh_pfc_gpio_pin {
25 	u8 dbit;
26 	u8 dreg;
27 };
28 
29 struct sh_pfc_chip {
30 	struct sh_pfc			*pfc;
31 	struct gpio_chip		gpio_chip;
32 
33 	struct sh_pfc_window		*mem;
34 	struct sh_pfc_gpio_data_reg	*regs;
35 	struct sh_pfc_gpio_pin		*pins;
36 };
37 
38 static struct sh_pfc *gpio_to_pfc(struct gpio_chip *gc)
39 {
40 	struct sh_pfc_chip *chip = gpiochip_get_data(gc);
41 	return chip->pfc;
42 }
43 
44 static void gpio_get_data_reg(struct sh_pfc_chip *chip, unsigned int offset,
45 			      struct sh_pfc_gpio_data_reg **reg,
46 			      unsigned int *bit)
47 {
48 	int idx = sh_pfc_get_pin_index(chip->pfc, offset);
49 	struct sh_pfc_gpio_pin *gpio_pin = &chip->pins[idx];
50 
51 	*reg = &chip->regs[gpio_pin->dreg];
52 	*bit = gpio_pin->dbit;
53 }
54 
55 static u32 gpio_read_data_reg(struct sh_pfc_chip *chip,
56 			      const struct pinmux_data_reg *dreg)
57 {
58 	phys_addr_t address = dreg->reg;
59 	void __iomem *mem = address - chip->mem->phys + chip->mem->virt;
60 
61 	return sh_pfc_read_raw_reg(mem, dreg->reg_width);
62 }
63 
64 static void gpio_write_data_reg(struct sh_pfc_chip *chip,
65 				const struct pinmux_data_reg *dreg, u32 value)
66 {
67 	phys_addr_t address = dreg->reg;
68 	void __iomem *mem = address - chip->mem->phys + chip->mem->virt;
69 
70 	sh_pfc_write_raw_reg(mem, dreg->reg_width, value);
71 }
72 
73 static void gpio_setup_data_reg(struct sh_pfc_chip *chip, unsigned idx)
74 {
75 	struct sh_pfc *pfc = chip->pfc;
76 	struct sh_pfc_gpio_pin *gpio_pin = &chip->pins[idx];
77 	const struct sh_pfc_pin *pin = &pfc->info->pins[idx];
78 	const struct pinmux_data_reg *dreg;
79 	unsigned int bit;
80 	unsigned int i;
81 
82 	for (i = 0, dreg = pfc->info->data_regs; dreg->reg_width; ++i, ++dreg) {
83 		for (bit = 0; bit < dreg->reg_width; bit++) {
84 			if (dreg->enum_ids[bit] == pin->enum_id) {
85 				gpio_pin->dreg = i;
86 				gpio_pin->dbit = bit;
87 				return;
88 			}
89 		}
90 	}
91 
92 	BUG();
93 }
94 
95 static int gpio_setup_data_regs(struct sh_pfc_chip *chip)
96 {
97 	struct sh_pfc *pfc = chip->pfc;
98 	const struct pinmux_data_reg *dreg;
99 	unsigned int i;
100 
101 	/* Count the number of data registers, allocate memory and initialize
102 	 * them.
103 	 */
104 	for (i = 0; pfc->info->data_regs[i].reg_width; ++i)
105 		;
106 
107 	chip->regs = devm_kcalloc(pfc->dev, i, sizeof(*chip->regs),
108 				  GFP_KERNEL);
109 	if (chip->regs == NULL)
110 		return -ENOMEM;
111 
112 	for (i = 0, dreg = pfc->info->data_regs; dreg->reg_width; ++i, ++dreg) {
113 		chip->regs[i].info = dreg;
114 		chip->regs[i].shadow = gpio_read_data_reg(chip, dreg);
115 	}
116 
117 	for (i = 0; i < pfc->info->nr_pins; i++) {
118 		if (pfc->info->pins[i].enum_id == 0)
119 			continue;
120 
121 		gpio_setup_data_reg(chip, i);
122 	}
123 
124 	return 0;
125 }
126 
127 /* -----------------------------------------------------------------------------
128  * Pin GPIOs
129  */
130 
131 static int gpio_pin_request(struct gpio_chip *gc, unsigned offset)
132 {
133 	struct sh_pfc *pfc = gpio_to_pfc(gc);
134 	int idx = sh_pfc_get_pin_index(pfc, offset);
135 
136 	if (idx < 0 || pfc->info->pins[idx].enum_id == 0)
137 		return -EINVAL;
138 
139 	return pinctrl_gpio_request(offset);
140 }
141 
142 static void gpio_pin_free(struct gpio_chip *gc, unsigned offset)
143 {
144 	return pinctrl_gpio_free(offset);
145 }
146 
147 static void gpio_pin_set_value(struct sh_pfc_chip *chip, unsigned offset,
148 			       int value)
149 {
150 	struct sh_pfc_gpio_data_reg *reg;
151 	unsigned int bit;
152 	unsigned int pos;
153 
154 	gpio_get_data_reg(chip, offset, &reg, &bit);
155 
156 	pos = reg->info->reg_width - (bit + 1);
157 
158 	if (value)
159 		reg->shadow |= BIT(pos);
160 	else
161 		reg->shadow &= ~BIT(pos);
162 
163 	gpio_write_data_reg(chip, reg->info, reg->shadow);
164 }
165 
166 static int gpio_pin_direction_input(struct gpio_chip *gc, unsigned offset)
167 {
168 	return pinctrl_gpio_direction_input(offset);
169 }
170 
171 static int gpio_pin_direction_output(struct gpio_chip *gc, unsigned offset,
172 				    int value)
173 {
174 	gpio_pin_set_value(gpiochip_get_data(gc), offset, value);
175 
176 	return pinctrl_gpio_direction_output(offset);
177 }
178 
179 static int gpio_pin_get(struct gpio_chip *gc, unsigned offset)
180 {
181 	struct sh_pfc_chip *chip = gpiochip_get_data(gc);
182 	struct sh_pfc_gpio_data_reg *reg;
183 	unsigned int bit;
184 	unsigned int pos;
185 
186 	gpio_get_data_reg(chip, offset, &reg, &bit);
187 
188 	pos = reg->info->reg_width - (bit + 1);
189 
190 	return (gpio_read_data_reg(chip, reg->info) >> pos) & 1;
191 }
192 
193 static void gpio_pin_set(struct gpio_chip *gc, unsigned offset, int value)
194 {
195 	gpio_pin_set_value(gpiochip_get_data(gc), offset, value);
196 }
197 
198 static int gpio_pin_to_irq(struct gpio_chip *gc, unsigned offset)
199 {
200 	struct sh_pfc *pfc = gpio_to_pfc(gc);
201 	unsigned int i, k;
202 
203 	for (i = 0; i < pfc->info->gpio_irq_size; i++) {
204 		const short *gpios = pfc->info->gpio_irq[i].gpios;
205 
206 		for (k = 0; gpios[k] >= 0; k++) {
207 			if (gpios[k] == offset)
208 				return pfc->irqs[i];
209 		}
210 	}
211 
212 	return 0;
213 }
214 
215 static int gpio_pin_setup(struct sh_pfc_chip *chip)
216 {
217 	struct sh_pfc *pfc = chip->pfc;
218 	struct gpio_chip *gc = &chip->gpio_chip;
219 	int ret;
220 
221 	chip->pins = devm_kcalloc(pfc->dev,
222 				  pfc->info->nr_pins, sizeof(*chip->pins),
223 				  GFP_KERNEL);
224 	if (chip->pins == NULL)
225 		return -ENOMEM;
226 
227 	ret = gpio_setup_data_regs(chip);
228 	if (ret < 0)
229 		return ret;
230 
231 	gc->request = gpio_pin_request;
232 	gc->free = gpio_pin_free;
233 	gc->direction_input = gpio_pin_direction_input;
234 	gc->get = gpio_pin_get;
235 	gc->direction_output = gpio_pin_direction_output;
236 	gc->set = gpio_pin_set;
237 	gc->to_irq = gpio_pin_to_irq;
238 
239 	gc->label = pfc->info->name;
240 	gc->parent = pfc->dev;
241 	gc->owner = THIS_MODULE;
242 	gc->base = 0;
243 	gc->ngpio = pfc->nr_gpio_pins;
244 
245 	return 0;
246 }
247 
248 /* -----------------------------------------------------------------------------
249  * Function GPIOs
250  */
251 
252 #ifdef CONFIG_PINCTRL_SH_FUNC_GPIO
253 static int gpio_function_request(struct gpio_chip *gc, unsigned offset)
254 {
255 	struct sh_pfc *pfc = gpio_to_pfc(gc);
256 	unsigned int mark = pfc->info->func_gpios[offset].enum_id;
257 	unsigned long flags;
258 	int ret;
259 
260 	dev_notice_once(pfc->dev,
261 			"Use of GPIO API for function requests is deprecated, convert to pinctrl\n");
262 
263 	if (mark == 0)
264 		return -EINVAL;
265 
266 	spin_lock_irqsave(&pfc->lock, flags);
267 	ret = sh_pfc_config_mux(pfc, mark, PINMUX_TYPE_FUNCTION);
268 	spin_unlock_irqrestore(&pfc->lock, flags);
269 
270 	return ret;
271 }
272 
273 static int gpio_function_setup(struct sh_pfc_chip *chip)
274 {
275 	struct sh_pfc *pfc = chip->pfc;
276 	struct gpio_chip *gc = &chip->gpio_chip;
277 
278 	gc->request = gpio_function_request;
279 
280 	gc->label = pfc->info->name;
281 	gc->owner = THIS_MODULE;
282 	gc->base = pfc->nr_gpio_pins;
283 	gc->ngpio = pfc->info->nr_func_gpios;
284 
285 	return 0;
286 }
287 #endif /* CONFIG_PINCTRL_SH_FUNC_GPIO */
288 
289 /* -----------------------------------------------------------------------------
290  * Register/unregister
291  */
292 
293 static struct sh_pfc_chip *
294 sh_pfc_add_gpiochip(struct sh_pfc *pfc, int(*setup)(struct sh_pfc_chip *),
295 		    struct sh_pfc_window *mem)
296 {
297 	struct sh_pfc_chip *chip;
298 	int ret;
299 
300 	chip = devm_kzalloc(pfc->dev, sizeof(*chip), GFP_KERNEL);
301 	if (unlikely(!chip))
302 		return ERR_PTR(-ENOMEM);
303 
304 	chip->mem = mem;
305 	chip->pfc = pfc;
306 
307 	ret = setup(chip);
308 	if (ret < 0)
309 		return ERR_PTR(ret);
310 
311 	ret = devm_gpiochip_add_data(pfc->dev, &chip->gpio_chip, chip);
312 	if (unlikely(ret < 0))
313 		return ERR_PTR(ret);
314 
315 	dev_info(pfc->dev, "%s handling gpio %u -> %u\n",
316 		 chip->gpio_chip.label, chip->gpio_chip.base,
317 		 chip->gpio_chip.base + chip->gpio_chip.ngpio - 1);
318 
319 	return chip;
320 }
321 
322 int sh_pfc_register_gpiochip(struct sh_pfc *pfc)
323 {
324 	struct sh_pfc_chip *chip;
325 	phys_addr_t address;
326 	unsigned int i;
327 
328 	if (pfc->info->data_regs == NULL)
329 		return 0;
330 
331 	/* Find the memory window that contain the GPIO registers. Boards that
332 	 * register a separate GPIO device will not supply a memory resource
333 	 * that covers the data registers. In that case don't try to handle
334 	 * GPIOs.
335 	 */
336 	address = pfc->info->data_regs[0].reg;
337 	for (i = 0; i < pfc->num_windows; ++i) {
338 		struct sh_pfc_window *window = &pfc->windows[i];
339 
340 		if (address >= window->phys &&
341 		    address < window->phys + window->size)
342 			break;
343 	}
344 
345 	if (i == pfc->num_windows)
346 		return 0;
347 
348 	/* If we have IRQ resources make sure their number is correct. */
349 	if (pfc->num_irqs != pfc->info->gpio_irq_size) {
350 		dev_err(pfc->dev, "invalid number of IRQ resources\n");
351 		return -EINVAL;
352 	}
353 
354 	/* Register the real GPIOs chip. */
355 	chip = sh_pfc_add_gpiochip(pfc, gpio_pin_setup, &pfc->windows[i]);
356 	if (IS_ERR(chip))
357 		return PTR_ERR(chip);
358 
359 	pfc->gpio = chip;
360 
361 	if (IS_ENABLED(CONFIG_OF) && pfc->dev->of_node)
362 		return 0;
363 
364 #ifdef CONFIG_PINCTRL_SH_FUNC_GPIO
365 	/*
366 	 * Register the GPIO to pin mappings. As pins with GPIO ports
367 	 * must come first in the ranges, skip the pins without GPIO
368 	 * ports by stopping at the first range that contains such a
369 	 * pin.
370 	 */
371 	for (i = 0; i < pfc->nr_ranges; ++i) {
372 		const struct sh_pfc_pin_range *range = &pfc->ranges[i];
373 		int ret;
374 
375 		if (range->start >= pfc->nr_gpio_pins)
376 			break;
377 
378 		ret = gpiochip_add_pin_range(&chip->gpio_chip,
379 			dev_name(pfc->dev), range->start, range->start,
380 			range->end - range->start + 1);
381 		if (ret < 0)
382 			return ret;
383 	}
384 
385 	/* Register the function GPIOs chip. */
386 	if (pfc->info->nr_func_gpios) {
387 		chip = sh_pfc_add_gpiochip(pfc, gpio_function_setup, NULL);
388 		if (IS_ERR(chip))
389 			return PTR_ERR(chip);
390 	}
391 #endif /* CONFIG_PINCTRL_SH_FUNC_GPIO */
392 
393 	return 0;
394 }
395