1 // SPDX-License-Identifier: GPL-2.0-or-later
2 /*
3 * GPIO driver for the SMSC SCH311x Super-I/O chips
4 *
5 * Copyright (C) 2013 Bruno Randolf <br1@einfach.org>
6 *
7 * SuperIO functions and chip detection:
8 * (c) Copyright 2008 Wim Van Sebroeck <wim@iguana.be>.
9 */
10
11 #include <linux/ioport.h>
12 #include <linux/module.h>
13 #include <linux/kernel.h>
14 #include <linux/init.h>
15 #include <linux/platform_device.h>
16 #include <linux/gpio/driver.h>
17 #include <linux/bitops.h>
18 #include <linux/io.h>
19
20 #define DRV_NAME "gpio-sch311x"
21
22 #define SCH311X_GPIO_CONF_DIR BIT(0)
23 #define SCH311X_GPIO_CONF_INVERT BIT(1)
24 #define SCH311X_GPIO_CONF_OPEN_DRAIN BIT(7)
25
26 #define SIO_CONFIG_KEY_ENTER 0x55
27 #define SIO_CONFIG_KEY_EXIT 0xaa
28
29 #define GP1 0x4b
30
31 static int sch311x_ioports[] = { 0x2e, 0x4e, 0x162e, 0x164e };
32
33 static struct platform_device *sch311x_gpio_pdev;
34
35 struct sch311x_pdev_data { /* platform device data */
36 unsigned short runtime_reg; /* runtime register base address */
37 };
38
39 struct sch311x_gpio_block { /* one GPIO block runtime data */
40 struct gpio_chip chip;
41 unsigned short data_reg; /* from definition below */
42 unsigned short *config_regs; /* pointer to definition below */
43 unsigned short runtime_reg; /* runtime register */
44 spinlock_t lock; /* lock for this GPIO block */
45 };
46
47 struct sch311x_gpio_priv { /* driver private data */
48 struct sch311x_gpio_block blocks[6];
49 };
50
51 struct sch311x_gpio_block_def { /* register address definitions */
52 unsigned short data_reg;
53 unsigned short config_regs[8];
54 unsigned short base;
55 };
56
57 /* Note: some GPIOs are not available, these are marked with 0x00 */
58
59 static struct sch311x_gpio_block_def sch311x_gpio_blocks[] = {
60 {
61 .data_reg = 0x4b, /* GP1 */
62 .config_regs = {0x23, 0x24, 0x25, 0x26, 0x27, 0x29, 0x2a, 0x2b},
63 .base = 10,
64 },
65 {
66 .data_reg = 0x4c, /* GP2 */
67 .config_regs = {0x00, 0x2c, 0x2d, 0x00, 0x00, 0x00, 0x00, 0x32},
68 .base = 20,
69 },
70 {
71 .data_reg = 0x4d, /* GP3 */
72 .config_regs = {0x33, 0x34, 0x35, 0x36, 0x37, 0x00, 0x39, 0x3a},
73 .base = 30,
74 },
75 {
76 .data_reg = 0x4e, /* GP4 */
77 .config_regs = {0x3b, 0x00, 0x3d, 0x00, 0x6e, 0x6f, 0x72, 0x73},
78 .base = 40,
79 },
80 {
81 .data_reg = 0x4f, /* GP5 */
82 .config_regs = {0x3f, 0x40, 0x41, 0x42, 0x43, 0x44, 0x45, 0x46},
83 .base = 50,
84 },
85 {
86 .data_reg = 0x50, /* GP6 */
87 .config_regs = {0x47, 0x48, 0x54, 0x55, 0x56, 0x57, 0x58, 0x59},
88 .base = 60,
89 },
90 };
91
92 /*
93 * Super-IO functions
94 */
95
sch311x_sio_enter(int sio_config_port)96 static inline int sch311x_sio_enter(int sio_config_port)
97 {
98 /* Don't step on other drivers' I/O space by accident. */
99 if (!request_muxed_region(sio_config_port, 2, DRV_NAME)) {
100 pr_err(DRV_NAME "I/O address 0x%04x already in use\n",
101 sio_config_port);
102 return -EBUSY;
103 }
104
105 outb(SIO_CONFIG_KEY_ENTER, sio_config_port);
106 return 0;
107 }
108
sch311x_sio_exit(int sio_config_port)109 static inline void sch311x_sio_exit(int sio_config_port)
110 {
111 outb(SIO_CONFIG_KEY_EXIT, sio_config_port);
112 release_region(sio_config_port, 2);
113 }
114
sch311x_sio_inb(int sio_config_port,int reg)115 static inline int sch311x_sio_inb(int sio_config_port, int reg)
116 {
117 outb(reg, sio_config_port);
118 return inb(sio_config_port + 1);
119 }
120
sch311x_sio_outb(int sio_config_port,int reg,int val)121 static inline void sch311x_sio_outb(int sio_config_port, int reg, int val)
122 {
123 outb(reg, sio_config_port);
124 outb(val, sio_config_port + 1);
125 }
126
127
128 /*
129 * GPIO functions
130 */
131
sch311x_gpio_request(struct gpio_chip * chip,unsigned offset)132 static int sch311x_gpio_request(struct gpio_chip *chip, unsigned offset)
133 {
134 struct sch311x_gpio_block *block = gpiochip_get_data(chip);
135
136 if (block->config_regs[offset] == 0) /* GPIO is not available */
137 return -ENODEV;
138
139 if (!request_region(block->runtime_reg + block->config_regs[offset],
140 1, DRV_NAME)) {
141 dev_err(chip->parent, "Failed to request region 0x%04x.\n",
142 block->runtime_reg + block->config_regs[offset]);
143 return -EBUSY;
144 }
145 return 0;
146 }
147
sch311x_gpio_free(struct gpio_chip * chip,unsigned offset)148 static void sch311x_gpio_free(struct gpio_chip *chip, unsigned offset)
149 {
150 struct sch311x_gpio_block *block = gpiochip_get_data(chip);
151
152 if (block->config_regs[offset] == 0) /* GPIO is not available */
153 return;
154
155 release_region(block->runtime_reg + block->config_regs[offset], 1);
156 }
157
sch311x_gpio_get(struct gpio_chip * chip,unsigned offset)158 static int sch311x_gpio_get(struct gpio_chip *chip, unsigned offset)
159 {
160 struct sch311x_gpio_block *block = gpiochip_get_data(chip);
161 u8 data;
162
163 spin_lock(&block->lock);
164 data = inb(block->runtime_reg + block->data_reg);
165 spin_unlock(&block->lock);
166
167 return !!(data & BIT(offset));
168 }
169
__sch311x_gpio_set(struct sch311x_gpio_block * block,unsigned offset,int value)170 static void __sch311x_gpio_set(struct sch311x_gpio_block *block,
171 unsigned offset, int value)
172 {
173 u8 data = inb(block->runtime_reg + block->data_reg);
174 if (value)
175 data |= BIT(offset);
176 else
177 data &= ~BIT(offset);
178 outb(data, block->runtime_reg + block->data_reg);
179 }
180
sch311x_gpio_set(struct gpio_chip * chip,unsigned offset,int value)181 static void sch311x_gpio_set(struct gpio_chip *chip, unsigned offset,
182 int value)
183 {
184 struct sch311x_gpio_block *block = gpiochip_get_data(chip);
185
186 spin_lock(&block->lock);
187 __sch311x_gpio_set(block, offset, value);
188 spin_unlock(&block->lock);
189 }
190
sch311x_gpio_direction_in(struct gpio_chip * chip,unsigned offset)191 static int sch311x_gpio_direction_in(struct gpio_chip *chip, unsigned offset)
192 {
193 struct sch311x_gpio_block *block = gpiochip_get_data(chip);
194 u8 data;
195
196 spin_lock(&block->lock);
197 data = inb(block->runtime_reg + block->config_regs[offset]);
198 data |= SCH311X_GPIO_CONF_DIR;
199 outb(data, block->runtime_reg + block->config_regs[offset]);
200 spin_unlock(&block->lock);
201
202 return 0;
203 }
204
sch311x_gpio_direction_out(struct gpio_chip * chip,unsigned offset,int value)205 static int sch311x_gpio_direction_out(struct gpio_chip *chip, unsigned offset,
206 int value)
207 {
208 struct sch311x_gpio_block *block = gpiochip_get_data(chip);
209 u8 data;
210
211 spin_lock(&block->lock);
212
213 data = inb(block->runtime_reg + block->config_regs[offset]);
214 data &= ~SCH311X_GPIO_CONF_DIR;
215 outb(data, block->runtime_reg + block->config_regs[offset]);
216 __sch311x_gpio_set(block, offset, value);
217
218 spin_unlock(&block->lock);
219 return 0;
220 }
221
sch311x_gpio_get_direction(struct gpio_chip * chip,unsigned offset)222 static int sch311x_gpio_get_direction(struct gpio_chip *chip, unsigned offset)
223 {
224 struct sch311x_gpio_block *block = gpiochip_get_data(chip);
225 u8 data;
226
227 spin_lock(&block->lock);
228 data = inb(block->runtime_reg + block->config_regs[offset]);
229 spin_unlock(&block->lock);
230
231 return !!(data & SCH311X_GPIO_CONF_DIR);
232 }
233
sch311x_gpio_set_config(struct gpio_chip * chip,unsigned offset,unsigned long config)234 static int sch311x_gpio_set_config(struct gpio_chip *chip, unsigned offset,
235 unsigned long config)
236 {
237 struct sch311x_gpio_block *block = gpiochip_get_data(chip);
238 enum pin_config_param param = pinconf_to_config_param(config);
239 u8 data;
240
241 switch (param) {
242 case PIN_CONFIG_DRIVE_OPEN_DRAIN:
243 spin_lock(&block->lock);
244 data = inb(block->runtime_reg + block->config_regs[offset]);
245 data |= SCH311X_GPIO_CONF_OPEN_DRAIN;
246 outb(data, block->runtime_reg + block->config_regs[offset]);
247 spin_unlock(&block->lock);
248 return 0;
249 case PIN_CONFIG_DRIVE_PUSH_PULL:
250 spin_lock(&block->lock);
251 data = inb(block->runtime_reg + block->config_regs[offset]);
252 data &= ~SCH311X_GPIO_CONF_OPEN_DRAIN;
253 outb(data, block->runtime_reg + block->config_regs[offset]);
254 spin_unlock(&block->lock);
255 return 0;
256 default:
257 break;
258 }
259 return -ENOTSUPP;
260 }
261
sch311x_gpio_probe(struct platform_device * pdev)262 static int sch311x_gpio_probe(struct platform_device *pdev)
263 {
264 struct sch311x_pdev_data *pdata = dev_get_platdata(&pdev->dev);
265 struct sch311x_gpio_priv *priv;
266 struct sch311x_gpio_block *block;
267 int err, i;
268
269 /* we can register all GPIO data registers at once */
270 if (!devm_request_region(&pdev->dev, pdata->runtime_reg + GP1, 6,
271 DRV_NAME)) {
272 dev_err(&pdev->dev, "Failed to request region 0x%04x-0x%04x.\n",
273 pdata->runtime_reg + GP1, pdata->runtime_reg + GP1 + 5);
274 return -EBUSY;
275 }
276
277 priv = devm_kzalloc(&pdev->dev, sizeof(*priv), GFP_KERNEL);
278 if (!priv)
279 return -ENOMEM;
280
281 platform_set_drvdata(pdev, priv);
282
283 for (i = 0; i < ARRAY_SIZE(priv->blocks); i++) {
284 block = &priv->blocks[i];
285
286 spin_lock_init(&block->lock);
287
288 block->chip.label = DRV_NAME;
289 block->chip.owner = THIS_MODULE;
290 block->chip.request = sch311x_gpio_request;
291 block->chip.free = sch311x_gpio_free;
292 block->chip.direction_input = sch311x_gpio_direction_in;
293 block->chip.direction_output = sch311x_gpio_direction_out;
294 block->chip.get_direction = sch311x_gpio_get_direction;
295 block->chip.set_config = sch311x_gpio_set_config;
296 block->chip.get = sch311x_gpio_get;
297 block->chip.set = sch311x_gpio_set;
298 block->chip.ngpio = 8;
299 block->chip.parent = &pdev->dev;
300 block->chip.base = sch311x_gpio_blocks[i].base;
301 block->config_regs = sch311x_gpio_blocks[i].config_regs;
302 block->data_reg = sch311x_gpio_blocks[i].data_reg;
303 block->runtime_reg = pdata->runtime_reg;
304
305 err = gpiochip_add_data(&block->chip, block);
306 if (err < 0) {
307 dev_err(&pdev->dev,
308 "Could not register gpiochip, %d\n", err);
309 goto exit_err;
310 }
311 dev_info(&pdev->dev,
312 "SMSC SCH311x GPIO block %d registered.\n", i);
313 }
314
315 return 0;
316
317 exit_err:
318 /* release already registered chips */
319 for (--i; i >= 0; i--)
320 gpiochip_remove(&priv->blocks[i].chip);
321 return err;
322 }
323
sch311x_gpio_remove(struct platform_device * pdev)324 static int sch311x_gpio_remove(struct platform_device *pdev)
325 {
326 struct sch311x_gpio_priv *priv = platform_get_drvdata(pdev);
327 int i;
328
329 for (i = 0; i < ARRAY_SIZE(priv->blocks); i++) {
330 gpiochip_remove(&priv->blocks[i].chip);
331 dev_info(&pdev->dev,
332 "SMSC SCH311x GPIO block %d unregistered.\n", i);
333 }
334 return 0;
335 }
336
337 static struct platform_driver sch311x_gpio_driver = {
338 .driver.name = DRV_NAME,
339 .probe = sch311x_gpio_probe,
340 .remove = sch311x_gpio_remove,
341 };
342
343
344 /*
345 * Init & exit routines
346 */
347
sch311x_detect(int sio_config_port,unsigned short * addr)348 static int __init sch311x_detect(int sio_config_port, unsigned short *addr)
349 {
350 int err = 0, reg;
351 unsigned short base_addr;
352 u8 dev_id;
353
354 err = sch311x_sio_enter(sio_config_port);
355 if (err)
356 return err;
357
358 /* Check device ID. */
359 reg = sch311x_sio_inb(sio_config_port, 0x20);
360 switch (reg) {
361 case 0x7c: /* SCH3112 */
362 dev_id = 2;
363 break;
364 case 0x7d: /* SCH3114 */
365 dev_id = 4;
366 break;
367 case 0x7f: /* SCH3116 */
368 dev_id = 6;
369 break;
370 default:
371 err = -ENODEV;
372 goto exit;
373 }
374
375 /* Select logical device A (runtime registers) */
376 sch311x_sio_outb(sio_config_port, 0x07, 0x0a);
377
378 /* Check if Logical Device Register is currently active */
379 if ((sch311x_sio_inb(sio_config_port, 0x30) & 0x01) == 0)
380 pr_info("Seems that LDN 0x0a is not active...\n");
381
382 /* Get the base address of the runtime registers */
383 base_addr = (sch311x_sio_inb(sio_config_port, 0x60) << 8) |
384 sch311x_sio_inb(sio_config_port, 0x61);
385 if (!base_addr) {
386 pr_err("Base address not set\n");
387 err = -ENODEV;
388 goto exit;
389 }
390 *addr = base_addr;
391
392 pr_info("Found an SMSC SCH311%d chip at 0x%04x\n", dev_id, base_addr);
393
394 exit:
395 sch311x_sio_exit(sio_config_port);
396 return err;
397 }
398
sch311x_gpio_pdev_add(const unsigned short addr)399 static int __init sch311x_gpio_pdev_add(const unsigned short addr)
400 {
401 struct sch311x_pdev_data pdata;
402 int err;
403
404 pdata.runtime_reg = addr;
405
406 sch311x_gpio_pdev = platform_device_alloc(DRV_NAME, -1);
407 if (!sch311x_gpio_pdev)
408 return -ENOMEM;
409
410 err = platform_device_add_data(sch311x_gpio_pdev,
411 &pdata, sizeof(pdata));
412 if (err) {
413 pr_err(DRV_NAME "Platform data allocation failed\n");
414 goto err;
415 }
416
417 err = platform_device_add(sch311x_gpio_pdev);
418 if (err) {
419 pr_err(DRV_NAME "Device addition failed\n");
420 goto err;
421 }
422 return 0;
423
424 err:
425 platform_device_put(sch311x_gpio_pdev);
426 return err;
427 }
428
sch311x_gpio_init(void)429 static int __init sch311x_gpio_init(void)
430 {
431 int err, i;
432 unsigned short addr = 0;
433
434 for (i = 0; i < ARRAY_SIZE(sch311x_ioports); i++)
435 if (sch311x_detect(sch311x_ioports[i], &addr) == 0)
436 break;
437
438 if (!addr)
439 return -ENODEV;
440
441 err = platform_driver_register(&sch311x_gpio_driver);
442 if (err)
443 return err;
444
445 err = sch311x_gpio_pdev_add(addr);
446 if (err)
447 goto unreg_platform_driver;
448
449 return 0;
450
451 unreg_platform_driver:
452 platform_driver_unregister(&sch311x_gpio_driver);
453 return err;
454 }
455
sch311x_gpio_exit(void)456 static void __exit sch311x_gpio_exit(void)
457 {
458 platform_device_unregister(sch311x_gpio_pdev);
459 platform_driver_unregister(&sch311x_gpio_driver);
460 }
461
462 module_init(sch311x_gpio_init);
463 module_exit(sch311x_gpio_exit);
464
465 MODULE_AUTHOR("Bruno Randolf <br1@einfach.org>");
466 MODULE_DESCRIPTION("SMSC SCH311x GPIO Driver");
467 MODULE_LICENSE("GPL");
468 MODULE_ALIAS("platform:gpio-sch311x");
469