xref: /openbmc/linux/drivers/gpio/gpio-f7188x.c (revision 6774def6) 
1 /*
2  * GPIO driver for Fintek Super-I/O F71882 and F71889
3  *
4  * Copyright (C) 2010-2013 LaCie
5  *
6  * Author: Simon Guinot <simon.guinot@sequanux.org>
7  *
8  * This program is free software; you can redistribute it and/or modify
9  * it under the terms of the GNU General Public License as published by
10  * the Free Software Foundation; either version 2 of the License, or
11  * (at your option) any later version.
12  */
13 
14 #include <linux/module.h>
15 #include <linux/init.h>
16 #include <linux/platform_device.h>
17 #include <linux/io.h>
18 #include <linux/gpio.h>
19 
20 #define DRVNAME "gpio-f7188x"
21 
22 /*
23  * Super-I/O registers
24  */
25 #define SIO_LDSEL		0x07	/* Logical device select */
26 #define SIO_DEVID		0x20	/* Device ID (2 bytes) */
27 #define SIO_DEVREV		0x22	/* Device revision */
28 #define SIO_MANID		0x23	/* Fintek ID (2 bytes) */
29 
30 #define SIO_LD_GPIO		0x06	/* GPIO logical device */
31 #define SIO_UNLOCK_KEY		0x87	/* Key to enable Super-I/O */
32 #define SIO_LOCK_KEY		0xAA	/* Key to disable Super-I/O */
33 
34 #define SIO_FINTEK_ID		0x1934	/* Manufacturer ID */
35 #define SIO_F71882_ID		0x0541	/* F71882 chipset ID */
36 #define SIO_F71889_ID		0x0909	/* F71889 chipset ID */
37 
38 enum chips { f71882fg, f71889f };
39 
40 static const char * const f7188x_names[] = {
41 	"f71882fg",
42 	"f71889f",
43 };
44 
45 struct f7188x_sio {
46 	int addr;
47 	enum chips type;
48 };
49 
50 struct f7188x_gpio_bank {
51 	struct gpio_chip chip;
52 	unsigned int regbase;
53 	struct f7188x_gpio_data *data;
54 };
55 
56 struct f7188x_gpio_data {
57 	struct f7188x_sio *sio;
58 	int nr_bank;
59 	struct f7188x_gpio_bank *bank;
60 };
61 
62 /*
63  * Super-I/O functions.
64  */
65 
66 static inline int superio_inb(int base, int reg)
67 {
68 	outb(reg, base);
69 	return inb(base + 1);
70 }
71 
72 static int superio_inw(int base, int reg)
73 {
74 	int val;
75 
76 	outb(reg++, base);
77 	val = inb(base + 1) << 8;
78 	outb(reg, base);
79 	val |= inb(base + 1);
80 
81 	return val;
82 }
83 
84 static inline void superio_outb(int base, int reg, int val)
85 {
86 	outb(reg, base);
87 	outb(val, base + 1);
88 }
89 
90 static inline int superio_enter(int base)
91 {
92 	/* Don't step on other drivers' I/O space by accident. */
93 	if (!request_muxed_region(base, 2, DRVNAME)) {
94 		pr_err(DRVNAME "I/O address 0x%04x already in use\n", base);
95 		return -EBUSY;
96 	}
97 
98 	/* According to the datasheet the key must be send twice. */
99 	outb(SIO_UNLOCK_KEY, base);
100 	outb(SIO_UNLOCK_KEY, base);
101 
102 	return 0;
103 }
104 
105 static inline void superio_select(int base, int ld)
106 {
107 	outb(SIO_LDSEL, base);
108 	outb(ld, base + 1);
109 }
110 
111 static inline void superio_exit(int base)
112 {
113 	outb(SIO_LOCK_KEY, base);
114 	release_region(base, 2);
115 }
116 
117 /*
118  * GPIO chip.
119  */
120 
121 static int f7188x_gpio_direction_in(struct gpio_chip *chip, unsigned offset);
122 static int f7188x_gpio_get(struct gpio_chip *chip, unsigned offset);
123 static int f7188x_gpio_direction_out(struct gpio_chip *chip,
124 				     unsigned offset, int value);
125 static void f7188x_gpio_set(struct gpio_chip *chip, unsigned offset, int value);
126 
127 #define F7188X_GPIO_BANK(_base, _ngpio, _regbase)			\
128 	{								\
129 		.chip = {						\
130 			.label            = DRVNAME,			\
131 			.owner            = THIS_MODULE,		\
132 			.direction_input  = f7188x_gpio_direction_in,	\
133 			.get              = f7188x_gpio_get,		\
134 			.direction_output = f7188x_gpio_direction_out,	\
135 			.set              = f7188x_gpio_set,		\
136 			.base             = _base,			\
137 			.ngpio            = _ngpio,			\
138 			.can_sleep        = true,			\
139 		},							\
140 		.regbase = _regbase,					\
141 	}
142 
143 #define gpio_dir(base) (base + 0)
144 #define gpio_data_out(base) (base + 1)
145 #define gpio_data_in(base) (base + 2)
146 /* Output mode register (0:open drain 1:push-pull). */
147 #define gpio_out_mode(base) (base + 3)
148 
149 static struct f7188x_gpio_bank f71882_gpio_bank[] = {
150 	F7188X_GPIO_BANK(0 , 8, 0xF0),
151 	F7188X_GPIO_BANK(10, 8, 0xE0),
152 	F7188X_GPIO_BANK(20, 8, 0xD0),
153 	F7188X_GPIO_BANK(30, 4, 0xC0),
154 	F7188X_GPIO_BANK(40, 4, 0xB0),
155 };
156 
157 static struct f7188x_gpio_bank f71889_gpio_bank[] = {
158 	F7188X_GPIO_BANK(0 , 7, 0xF0),
159 	F7188X_GPIO_BANK(10, 7, 0xE0),
160 	F7188X_GPIO_BANK(20, 8, 0xD0),
161 	F7188X_GPIO_BANK(30, 8, 0xC0),
162 	F7188X_GPIO_BANK(40, 8, 0xB0),
163 	F7188X_GPIO_BANK(50, 5, 0xA0),
164 	F7188X_GPIO_BANK(60, 8, 0x90),
165 	F7188X_GPIO_BANK(70, 8, 0x80),
166 };
167 
168 static int f7188x_gpio_direction_in(struct gpio_chip *chip, unsigned offset)
169 {
170 	int err;
171 	struct f7188x_gpio_bank *bank =
172 		container_of(chip, struct f7188x_gpio_bank, chip);
173 	struct f7188x_sio *sio = bank->data->sio;
174 	u8 dir;
175 
176 	err = superio_enter(sio->addr);
177 	if (err)
178 		return err;
179 	superio_select(sio->addr, SIO_LD_GPIO);
180 
181 	dir = superio_inb(sio->addr, gpio_dir(bank->regbase));
182 	dir &= ~(1 << offset);
183 	superio_outb(sio->addr, gpio_dir(bank->regbase), dir);
184 
185 	superio_exit(sio->addr);
186 
187 	return 0;
188 }
189 
190 static int f7188x_gpio_get(struct gpio_chip *chip, unsigned offset)
191 {
192 	int err;
193 	struct f7188x_gpio_bank *bank =
194 		container_of(chip, struct f7188x_gpio_bank, chip);
195 	struct f7188x_sio *sio = bank->data->sio;
196 	u8 dir, data;
197 
198 	err = superio_enter(sio->addr);
199 	if (err)
200 		return err;
201 	superio_select(sio->addr, SIO_LD_GPIO);
202 
203 	dir = superio_inb(sio->addr, gpio_dir(bank->regbase));
204 	dir = !!(dir & (1 << offset));
205 	if (dir)
206 		data = superio_inb(sio->addr, gpio_data_out(bank->regbase));
207 	else
208 		data = superio_inb(sio->addr, gpio_data_in(bank->regbase));
209 
210 	superio_exit(sio->addr);
211 
212 	return !!(data & 1 << offset);
213 }
214 
215 static int f7188x_gpio_direction_out(struct gpio_chip *chip,
216 				     unsigned offset, int value)
217 {
218 	int err;
219 	struct f7188x_gpio_bank *bank =
220 		container_of(chip, struct f7188x_gpio_bank, chip);
221 	struct f7188x_sio *sio = bank->data->sio;
222 	u8 dir, data_out;
223 
224 	err = superio_enter(sio->addr);
225 	if (err)
226 		return err;
227 	superio_select(sio->addr, SIO_LD_GPIO);
228 
229 	data_out = superio_inb(sio->addr, gpio_data_out(bank->regbase));
230 	if (value)
231 		data_out |= (1 << offset);
232 	else
233 		data_out &= ~(1 << offset);
234 	superio_outb(sio->addr, gpio_data_out(bank->regbase), data_out);
235 
236 	dir = superio_inb(sio->addr, gpio_dir(bank->regbase));
237 	dir |= (1 << offset);
238 	superio_outb(sio->addr, gpio_dir(bank->regbase), dir);
239 
240 	superio_exit(sio->addr);
241 
242 	return 0;
243 }
244 
245 static void f7188x_gpio_set(struct gpio_chip *chip, unsigned offset, int value)
246 {
247 	int err;
248 	struct f7188x_gpio_bank *bank =
249 		container_of(chip, struct f7188x_gpio_bank, chip);
250 	struct f7188x_sio *sio = bank->data->sio;
251 	u8 data_out;
252 
253 	err = superio_enter(sio->addr);
254 	if (err)
255 		return;
256 	superio_select(sio->addr, SIO_LD_GPIO);
257 
258 	data_out = superio_inb(sio->addr, gpio_data_out(bank->regbase));
259 	if (value)
260 		data_out |= (1 << offset);
261 	else
262 		data_out &= ~(1 << offset);
263 	superio_outb(sio->addr, gpio_data_out(bank->regbase), data_out);
264 
265 	superio_exit(sio->addr);
266 }
267 
268 /*
269  * Platform device and driver.
270  */
271 
272 static int f7188x_gpio_probe(struct platform_device *pdev)
273 {
274 	int err;
275 	int i;
276 	struct f7188x_sio *sio = pdev->dev.platform_data;
277 	struct f7188x_gpio_data *data;
278 
279 	data = devm_kzalloc(&pdev->dev, sizeof(*data), GFP_KERNEL);
280 	if (!data)
281 		return -ENOMEM;
282 
283 	switch (sio->type) {
284 	case f71882fg:
285 		data->nr_bank = ARRAY_SIZE(f71882_gpio_bank);
286 		data->bank = f71882_gpio_bank;
287 		break;
288 	case f71889f:
289 		data->nr_bank = ARRAY_SIZE(f71889_gpio_bank);
290 		data->bank = f71889_gpio_bank;
291 		break;
292 	default:
293 		return -ENODEV;
294 	}
295 	data->sio = sio;
296 
297 	platform_set_drvdata(pdev, data);
298 
299 	/* For each GPIO bank, register a GPIO chip. */
300 	for (i = 0; i < data->nr_bank; i++) {
301 		struct f7188x_gpio_bank *bank = &data->bank[i];
302 
303 		bank->chip.dev = &pdev->dev;
304 		bank->data = data;
305 
306 		err = gpiochip_add(&bank->chip);
307 		if (err) {
308 			dev_err(&pdev->dev,
309 				"Failed to register gpiochip %d: %d\n",
310 				i, err);
311 			goto err_gpiochip;
312 		}
313 	}
314 
315 	return 0;
316 
317 err_gpiochip:
318 	for (i = i - 1; i >= 0; i--) {
319 		struct f7188x_gpio_bank *bank = &data->bank[i];
320 		gpiochip_remove(&bank->chip);
321 	}
322 
323 	return err;
324 }
325 
326 static int f7188x_gpio_remove(struct platform_device *pdev)
327 {
328 	int i;
329 	struct f7188x_gpio_data *data = platform_get_drvdata(pdev);
330 
331 	for (i = 0; i < data->nr_bank; i++) {
332 		struct f7188x_gpio_bank *bank = &data->bank[i];
333 		gpiochip_remove(&bank->chip);
334 	}
335 
336 	return 0;
337 }
338 
339 static int __init f7188x_find(int addr, struct f7188x_sio *sio)
340 {
341 	int err;
342 	u16 devid;
343 
344 	err = superio_enter(addr);
345 	if (err)
346 		return err;
347 
348 	err = -ENODEV;
349 	devid = superio_inw(addr, SIO_MANID);
350 	if (devid != SIO_FINTEK_ID) {
351 		pr_debug(DRVNAME ": Not a Fintek device at 0x%08x\n", addr);
352 		goto err;
353 	}
354 
355 	devid = superio_inw(addr, SIO_DEVID);
356 	switch (devid) {
357 	case SIO_F71882_ID:
358 		sio->type = f71882fg;
359 		break;
360 	case SIO_F71889_ID:
361 		sio->type = f71889f;
362 		break;
363 	default:
364 		pr_info(DRVNAME ": Unsupported Fintek device 0x%04x\n", devid);
365 		goto err;
366 	}
367 	sio->addr = addr;
368 	err = 0;
369 
370 	pr_info(DRVNAME ": Found %s at %#x, revision %d\n",
371 		f7188x_names[sio->type],
372 		(unsigned int) addr,
373 		(int) superio_inb(addr, SIO_DEVREV));
374 
375 err:
376 	superio_exit(addr);
377 	return err;
378 }
379 
380 static struct platform_device *f7188x_gpio_pdev;
381 
382 static int __init
383 f7188x_gpio_device_add(const struct f7188x_sio *sio)
384 {
385 	int err;
386 
387 	f7188x_gpio_pdev = platform_device_alloc(DRVNAME, -1);
388 	if (!f7188x_gpio_pdev)
389 		return -ENOMEM;
390 
391 	err = platform_device_add_data(f7188x_gpio_pdev,
392 				       sio, sizeof(*sio));
393 	if (err) {
394 		pr_err(DRVNAME "Platform data allocation failed\n");
395 		goto err;
396 	}
397 
398 	err = platform_device_add(f7188x_gpio_pdev);
399 	if (err) {
400 		pr_err(DRVNAME "Device addition failed\n");
401 		goto err;
402 	}
403 
404 	return 0;
405 
406 err:
407 	platform_device_put(f7188x_gpio_pdev);
408 
409 	return err;
410 }
411 
412 /*
413  * Try to match a supported Fintech device by reading the (hard-wired)
414  * configuration I/O ports. If available, then register both the platform
415  * device and driver to support the GPIOs.
416  */
417 
418 static struct platform_driver f7188x_gpio_driver = {
419 	.driver = {
420 		.owner	= THIS_MODULE,
421 		.name	= DRVNAME,
422 	},
423 	.probe		= f7188x_gpio_probe,
424 	.remove		= f7188x_gpio_remove,
425 };
426 
427 static int __init f7188x_gpio_init(void)
428 {
429 	int err;
430 	struct f7188x_sio sio;
431 
432 	if (f7188x_find(0x2e, &sio) &&
433 	    f7188x_find(0x4e, &sio))
434 		return -ENODEV;
435 
436 	err = platform_driver_register(&f7188x_gpio_driver);
437 	if (!err) {
438 		err = f7188x_gpio_device_add(&sio);
439 		if (err)
440 			platform_driver_unregister(&f7188x_gpio_driver);
441 	}
442 
443 	return err;
444 }
445 subsys_initcall(f7188x_gpio_init);
446 
447 static void __exit f7188x_gpio_exit(void)
448 {
449 	platform_device_unregister(f7188x_gpio_pdev);
450 	platform_driver_unregister(&f7188x_gpio_driver);
451 }
452 module_exit(f7188x_gpio_exit);
453 
454 MODULE_DESCRIPTION("GPIO driver for Super-I/O chips F71882FG and F71889F");
455 MODULE_AUTHOR("Simon Guinot <simon.guinot@sequanux.org>");
456 MODULE_LICENSE("GPL");
457