1/*
2 * GPIO driver for the SMSC SCH311x Super-I/O chips
3 *
4 * Copyright (C) 2013 Bruno Randolf <br1@einfach.org>
5 *
6 * SuperIO functions and chip detection:
7 * (c) Copyright 2008 Wim Van Sebroeck <wim@iguana.be>.
8 *
9 * This program is free software; you can redistribute it and/or modify
10 * it under the terms of the GNU General Public License as published by
11 * the Free Software Foundation; either version 2 of the License, or
12 * (at your option) any later version.
13 */
14
15#include <linux/ioport.h>
16#include <linux/module.h>
17#include <linux/kernel.h>
18#include <linux/init.h>
19#include <linux/platform_device.h>
20#include <linux/gpio/driver.h>
21#include <linux/bitops.h>
22#include <linux/io.h>
23
24#define DRV_NAME "gpio-sch311x"
25
26#define SCH311X_GPIO_CONF_DIR BIT(0)
27#define SCH311X_GPIO_CONF_INVERT BIT(1)
28#define SCH311X_GPIO_CONF_OPEN_DRAIN BIT(7)
29
30#define SIO_CONFIG_KEY_ENTER 0x55
31#define SIO_CONFIG_KEY_EXIT 0xaa
32
33#define GP1 0x4b
34
35static int sch311x_ioports[] = { 0x2e, 0x4e, 0x162e, 0x164e };
36
37static struct platform_device *sch311x_gpio_pdev;
38
39struct sch311x_pdev_data { /* platform device data */
40 unsigned short runtime_reg; /* runtime register base address */
41};
42
43struct sch311x_gpio_block { /* one GPIO block runtime data */
44 struct gpio_chip chip;
45 unsigned short data_reg; /* from definition below */
46 unsigned short *config_regs; /* pointer to definition below */
47 unsigned short runtime_reg; /* runtime register */
48 spinlock_t lock; /* lock for this GPIO block */
49};
50
51struct sch311x_gpio_priv { /* driver private data */
52 struct sch311x_gpio_block blocks[6];
53};
54
55struct sch311x_gpio_block_def { /* register address definitions */
56 unsigned short data_reg;
57 unsigned short config_regs[8];
58 unsigned short base;
59};
60
61/* Note: some GPIOs are not available, these are marked with 0x00 */
62
63static struct sch311x_gpio_block_def sch311x_gpio_blocks[] = {
64 {
65 .data_reg = 0x4b, /* GP1 */
66 .config_regs = {0x23, 0x24, 0x25, 0x26, 0x27, 0x29, 0x2a, 0x2b},
67 .base = 10,
68 },
69 {
70 .data_reg = 0x4c, /* GP2 */
71 .config_regs = {0x00, 0x2c, 0x2d, 0x00, 0x00, 0x00, 0x00, 0x32},
72 .base = 20,
73 },
74 {
75 .data_reg = 0x4d, /* GP3 */
76 .config_regs = {0x33, 0x34, 0x35, 0x36, 0x37, 0x00, 0x39, 0x3a},
77 .base = 30,
78 },
79 {
80 .data_reg = 0x4e, /* GP4 */
81 .config_regs = {0x3b, 0x00, 0x3d, 0x00, 0x6e, 0x6f, 0x72, 0x73},
82 .base = 40,
83 },
84 {
85 .data_reg = 0x4f, /* GP5 */
86 .config_regs = {0x3f, 0x40, 0x41, 0x42, 0x43, 0x44, 0x45, 0x46},
87 .base = 50,
88 },
89 {
90 .data_reg = 0x50, /* GP6 */
91 .config_regs = {0x47, 0x48, 0x54, 0x55, 0x56, 0x57, 0x58, 0x59},
92 .base = 60,
93 },
94};
95
96/*
97 * Super-IO functions
98 */
99
100static inline int sch311x_sio_enter(int sio_config_port)
101{
102 /* Don't step on other drivers' I/O space by accident. */
103 if (!request_muxed_region(sio_config_port, 2, DRV_NAME)) {
104 pr_err(DRV_NAME "I/O address 0x%04x already in use\n",
105 sio_config_port);
106 return -EBUSY;
107 }
108
109 outb(SIO_CONFIG_KEY_ENTER, sio_config_port);
110 return 0;
111}
112
113static inline void sch311x_sio_exit(int sio_config_port)
114{
115 outb(SIO_CONFIG_KEY_EXIT, sio_config_port);
116 release_region(sio_config_port, 2);
117}
118
119static inline int sch311x_sio_inb(int sio_config_port, int reg)
120{
121 outb(reg, sio_config_port);
122 return inb(sio_config_port + 1);
123}
124
125static inline void sch311x_sio_outb(int sio_config_port, int reg, int val)
126{
127 outb(reg, sio_config_port);
128 outb(val, sio_config_port + 1);
129}
130
131
132/*
133 * GPIO functions
134 */
135
136static int sch311x_gpio_request(struct gpio_chip *chip, unsigned offset)
137{
138 struct sch311x_gpio_block *block = gpiochip_get_data(chip);
139
140 if (block->config_regs[offset] == 0) /* GPIO is not available */
141 return -ENODEV;
142
143 if (!request_region(block->runtime_reg + block->config_regs[offset],
144 1, DRV_NAME)) {
145 dev_err(chip->parent, "Failed to request region 0x%04x.\n",
146 block->runtime_reg + block->config_regs[offset]);
147 return -EBUSY;
148 }
149 return 0;
150}
151
152static void sch311x_gpio_free(struct gpio_chip *chip, unsigned offset)
153{
154 struct sch311x_gpio_block *block = gpiochip_get_data(chip);
155
156 if (block->config_regs[offset] == 0) /* GPIO is not available */
157 return;
158
159 release_region(block->runtime_reg + block->config_regs[offset], 1);
160}
161
162static int sch311x_gpio_get(struct gpio_chip *chip, unsigned offset)
163{
164 struct sch311x_gpio_block *block = gpiochip_get_data(chip);
165 u8 data;
166
167 spin_lock(&block->lock);
168 data = inb(block->runtime_reg + block->data_reg);
169 spin_unlock(&block->lock);
170
171 return !!(data & BIT(offset));
172}
173
174static void __sch311x_gpio_set(struct sch311x_gpio_block *block,
175 unsigned offset, int value)
176{
177 u8 data = inb(block->runtime_reg + block->data_reg);
178 if (value)
179 data |= BIT(offset);
180 else
181 data &= ~BIT(offset);
182 outb(data, block->runtime_reg + block->data_reg);
183}
184
185static void sch311x_gpio_set(struct gpio_chip *chip, unsigned offset,
186 int value)
187{
188 struct sch311x_gpio_block *block = gpiochip_get_data(chip);
189
190 spin_lock(&block->lock);
191 __sch311x_gpio_set(block, offset, value);
192 spin_unlock(&block->lock);
193}
194
195static int sch311x_gpio_direction_in(struct gpio_chip *chip, unsigned offset)
196{
197 struct sch311x_gpio_block *block = gpiochip_get_data(chip);
198 u8 data;
199
200 spin_lock(&block->lock);
201 data = inb(block->runtime_reg + block->config_regs[offset]);
202 data |= SCH311X_GPIO_CONF_DIR;
203 outb(data, block->runtime_reg + block->config_regs[offset]);
204 spin_unlock(&block->lock);
205
206 return 0;
207}
208
209static int sch311x_gpio_direction_out(struct gpio_chip *chip, unsigned offset,
210 int value)
211{
212 struct sch311x_gpio_block *block = gpiochip_get_data(chip);
213 u8 data;
214
215 spin_lock(&block->lock);
216
217 data = inb(block->runtime_reg + block->config_regs[offset]);
218 data &= ~SCH311X_GPIO_CONF_DIR;
219 outb(data, block->runtime_reg + block->config_regs[offset]);
220 __sch311x_gpio_set(block, offset, value);
221
222 spin_unlock(&block->lock);
223 return 0;
224}
225
226static int sch311x_gpio_get_direction(struct gpio_chip *chip, unsigned offset)
227{
228 struct sch311x_gpio_block *block = gpiochip_get_data(chip);
229 u8 data;
230
231 spin_lock(&block->lock);
232 data = inb(block->runtime_reg + block->config_regs[offset]);
233 spin_unlock(&block->lock);
234
235 return !!(data & SCH311X_GPIO_CONF_DIR);
236}
237
238static int sch311x_gpio_set_config(struct gpio_chip *chip, unsigned offset,
239 unsigned long config)
240{
241 struct sch311x_gpio_block *block = gpiochip_get_data(chip);
242 enum pin_config_param param = pinconf_to_config_param(config);
243 u8 data;
244
245 switch (param) {
246 case PIN_CONFIG_DRIVE_OPEN_DRAIN:
247 spin_lock(&block->lock);
248 data = inb(block->runtime_reg + block->config_regs[offset]);
249 data |= SCH311X_GPIO_CONF_OPEN_DRAIN;
250 outb(data, block->runtime_reg + block->config_regs[offset]);
251 spin_unlock(&block->lock);
252 return 0;
253 case PIN_CONFIG_DRIVE_PUSH_PULL:
254 spin_lock(&block->lock);
255 data = inb(block->runtime_reg + block->config_regs[offset]);
256 data &= ~SCH311X_GPIO_CONF_OPEN_DRAIN;
257 outb(data, block->runtime_reg + block->config_regs[offset]);
258 spin_unlock(&block->lock);
259 return 0;
260 default:
261 break;
262 }
263 return -ENOTSUPP;
264}
265
266static int sch311x_gpio_probe(struct platform_device *pdev)
267{
268 struct sch311x_pdev_data *pdata = dev_get_platdata(&pdev->dev);
269 struct sch311x_gpio_priv *priv;
270 struct sch311x_gpio_block *block;
271 int err, i;
272
273 /* we can register all GPIO data registers at once */
274 if (!devm_request_region(&pdev->dev, pdata->runtime_reg + GP1, 6,
275 DRV_NAME)) {
276 dev_err(&pdev->dev, "Failed to request region 0x%04x-0x%04x.\n",
277 pdata->runtime_reg + GP1, pdata->runtime_reg + GP1 + 5);
278 return -EBUSY;
279 }
280
281 priv = devm_kzalloc(&pdev->dev, sizeof(*priv), GFP_KERNEL);
282 if (!priv)
283 return -ENOMEM;
284
285 platform_set_drvdata(pdev, priv);
286
287 for (i = 0; i < ARRAY_SIZE(priv->blocks); i++) {
288 block = &priv->blocks[i];
289
290 spin_lock_init(&block->lock);
291
292 block->chip.label = DRV_NAME;
293 block->chip.owner = THIS_MODULE;
294 block->chip.request = sch311x_gpio_request;
295 block->chip.free = sch311x_gpio_free;
296 block->chip.direction_input = sch311x_gpio_direction_in;
297 block->chip.direction_output = sch311x_gpio_direction_out;
298 block->chip.get_direction = sch311x_gpio_get_direction;
299 block->chip.set_config = sch311x_gpio_set_config;
300 block->chip.get = sch311x_gpio_get;
301 block->chip.set = sch311x_gpio_set;
302 block->chip.ngpio = 8;
303 block->chip.parent = &pdev->dev;
304 block->chip.base = sch311x_gpio_blocks[i].base;
305 block->config_regs = sch311x_gpio_blocks[i].config_regs;
306 block->data_reg = sch311x_gpio_blocks[i].data_reg;
307 block->runtime_reg = pdata->runtime_reg;
308
309 err = gpiochip_add_data(&block->chip, block);
310 if (err < 0) {
311 dev_err(&pdev->dev,
312 "Could not register gpiochip, %d\n", err);
313 goto exit_err;
314 }
315 dev_info(&pdev->dev,
316 "SMSC SCH311x GPIO block %d registered.\n", i);
317 }
318
319 return 0;
320
321exit_err:
322 /* release already registered chips */
323 for (--i; i >= 0; i--)
324 gpiochip_remove(&priv->blocks[i].chip);
325 return err;
326}
327
328static int sch311x_gpio_remove(struct platform_device *pdev)
329{
330 struct sch311x_gpio_priv *priv = platform_get_drvdata(pdev);
331 int i;
332
333 for (i = 0; i < ARRAY_SIZE(priv->blocks); i++) {
334 gpiochip_remove(&priv->blocks[i].chip);
335 dev_info(&pdev->dev,
336 "SMSC SCH311x GPIO block %d unregistered.\n", i);
337 }
338 return 0;
339}
340
341static struct platform_driver sch311x_gpio_driver = {
342 .driver.name = DRV_NAME,
343 .probe = sch311x_gpio_probe,
344 .remove = sch311x_gpio_remove,
345};
346
347
348/*
349 * Init & exit routines
350 */
351
352static int __init sch311x_detect(int sio_config_port, unsigned short *addr)
353{
354 int err = 0, reg;
355 unsigned short base_addr;
356 u8 dev_id;
357
358 err = sch311x_sio_enter(sio_config_port);
359 if (err)
360 return err;
361
362 /* Check device ID. */
363 reg = sch311x_sio_inb(sio_config_port, 0x20);
364 switch (reg) {
365 case 0x7c: /* SCH3112 */
366 dev_id = 2;
367 break;
368 case 0x7d: /* SCH3114 */
369 dev_id = 4;
370 break;
371 case 0x7f: /* SCH3116 */
372 dev_id = 6;
373 break;
374 default:
375 err = -ENODEV;
376 goto exit;
377 }
378
379 /* Select logical device A (runtime registers) */
380 sch311x_sio_outb(sio_config_port, 0x07, 0x0a);
381
382 /* Check if Logical Device Register is currently active */
383 if ((sch311x_sio_inb(sio_config_port, 0x30) & 0x01) == 0)
384 pr_info("Seems that LDN 0x0a is not active...\n");
385
386 /* Get the base address of the runtime registers */
387 base_addr = (sch311x_sio_inb(sio_config_port, 0x60) << 8) |
388 sch311x_sio_inb(sio_config_port, 0x61);
389 if (!base_addr) {
390 pr_err("Base address not set\n");
391 err = -ENODEV;
392 goto exit;
393 }
394 *addr = base_addr;
395
396 pr_info("Found an SMSC SCH311%d chip at 0x%04x\n", dev_id, base_addr);
397
398exit:
399 sch311x_sio_exit(sio_config_port);
400 return err;
401}
402
403static int __init sch311x_gpio_pdev_add(const unsigned short addr)
404{
405 struct sch311x_pdev_data pdata;
406 int err;
407
408 pdata.runtime_reg = addr;
409
410 sch311x_gpio_pdev = platform_device_alloc(DRV_NAME, -1);
411 if (!sch311x_gpio_pdev)
412 return -ENOMEM;
413
414 err = platform_device_add_data(sch311x_gpio_pdev,
415 &pdata, sizeof(pdata));
416 if (err) {
417 pr_err(DRV_NAME "Platform data allocation failed\n");
418 goto err;
419 }
420
421 err = platform_device_add(sch311x_gpio_pdev);
422 if (err) {
423 pr_err(DRV_NAME "Device addition failed\n");
424 goto err;
425 }
426 return 0;
427
428err:
429 platform_device_put(sch311x_gpio_pdev);
430 return err;
431}
432
433static int __init sch311x_gpio_init(void)
434{
435 int err, i;
436 unsigned short addr = 0;
437
438 for (i = 0; i < ARRAY_SIZE(sch311x_ioports); i++)
439 if (sch311x_detect(sch311x_ioports[i], &addr) == 0)
440 break;
441
442 if (!addr)
443 return -ENODEV;
444
445 err = platform_driver_register(&sch311x_gpio_driver);
446 if (err)
447 return err;
448
449 err = sch311x_gpio_pdev_add(addr);
450 if (err)
451 goto unreg_platform_driver;
452
453 return 0;
454
455unreg_platform_driver:
456 platform_driver_unregister(&sch311x_gpio_driver);
457 return err;
458}
459
460static void __exit sch311x_gpio_exit(void)
461{
462 platform_device_unregister(sch311x_gpio_pdev);
463 platform_driver_unregister(&sch311x_gpio_driver);
464}
465
466module_init(sch311x_gpio_init);
467module_exit(sch311x_gpio_exit);
468
469MODULE_AUTHOR("Bruno Randolf <br1@einfach.org>");
470MODULE_DESCRIPTION("SMSC SCH311x GPIO Driver");
471MODULE_LICENSE("GPL");
472MODULE_ALIAS("platform:gpio-sch311x");
473