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
31static int sch311x_ioports[] = { 0x2e, 0x4e, 0x162e, 0x164e };
32
33static struct platform_device *sch311x_gpio_pdev;
34
35struct sch311x_pdev_data { /* platform device data */
36 unsigned short runtime_reg; /* runtime register base address */
37};
38
39struct 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
47struct sch311x_gpio_priv { /* driver private data */
48 struct sch311x_gpio_block blocks[6];
49};
50
51struct 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
59static 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
96static 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, port: sio_config_port);
106 return 0;
107}
108
109static inline void sch311x_sio_exit(int sio_config_port)
110{
111 outb(SIO_CONFIG_KEY_EXIT, port: sio_config_port);
112 release_region(sio_config_port, 2);
113}
114
115static inline int sch311x_sio_inb(int sio_config_port, int reg)
116{
117 outb(value: reg, port: sio_config_port);
118 return inb(port: sio_config_port + 1);
119}
120
121static inline void sch311x_sio_outb(int sio_config_port, int reg, int val)
122{
123 outb(value: reg, port: sio_config_port);
124 outb(value: val, port: sio_config_port + 1);
125}
126
127
128/*
129 * GPIO functions
130 */
131
132static int sch311x_gpio_request(struct gpio_chip *chip, unsigned offset)
133{
134 struct sch311x_gpio_block *block = gpiochip_get_data(gc: 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
148static void sch311x_gpio_free(struct gpio_chip *chip, unsigned offset)
149{
150 struct sch311x_gpio_block *block = gpiochip_get_data(gc: 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
158static int sch311x_gpio_get(struct gpio_chip *chip, unsigned offset)
159{
160 struct sch311x_gpio_block *block = gpiochip_get_data(gc: chip);
161 u8 data;
162
163 spin_lock(lock: &block->lock);
164 data = inb(port: block->runtime_reg + block->data_reg);
165 spin_unlock(lock: &block->lock);
166
167 return !!(data & BIT(offset));
168}
169
170static void __sch311x_gpio_set(struct sch311x_gpio_block *block,
171 unsigned offset, int value)
172{
173 u8 data = inb(port: block->runtime_reg + block->data_reg);
174 if (value)
175 data |= BIT(offset);
176 else
177 data &= ~BIT(offset);
178 outb(value: data, port: block->runtime_reg + block->data_reg);
179}
180
181static void sch311x_gpio_set(struct gpio_chip *chip, unsigned offset,
182 int value)
183{
184 struct sch311x_gpio_block *block = gpiochip_get_data(gc: chip);
185
186 spin_lock(lock: &block->lock);
187 __sch311x_gpio_set(block, offset, value);
188 spin_unlock(lock: &block->lock);
189}
190
191static int sch311x_gpio_direction_in(struct gpio_chip *chip, unsigned offset)
192{
193 struct sch311x_gpio_block *block = gpiochip_get_data(gc: chip);
194 u8 data;
195
196 spin_lock(lock: &block->lock);
197 data = inb(port: block->runtime_reg + block->config_regs[offset]);
198 data |= SCH311X_GPIO_CONF_DIR;
199 outb(value: data, port: block->runtime_reg + block->config_regs[offset]);
200 spin_unlock(lock: &block->lock);
201
202 return 0;
203}
204
205static int sch311x_gpio_direction_out(struct gpio_chip *chip, unsigned offset,
206 int value)
207{
208 struct sch311x_gpio_block *block = gpiochip_get_data(gc: chip);
209 u8 data;
210
211 spin_lock(lock: &block->lock);
212
213 data = inb(port: block->runtime_reg + block->config_regs[offset]);
214 data &= ~SCH311X_GPIO_CONF_DIR;
215 outb(value: data, port: block->runtime_reg + block->config_regs[offset]);
216 __sch311x_gpio_set(block, offset, value);
217
218 spin_unlock(lock: &block->lock);
219 return 0;
220}
221
222static int sch311x_gpio_get_direction(struct gpio_chip *chip, unsigned offset)
223{
224 struct sch311x_gpio_block *block = gpiochip_get_data(gc: chip);
225 u8 data;
226
227 spin_lock(lock: &block->lock);
228 data = inb(port: block->runtime_reg + block->config_regs[offset]);
229 spin_unlock(lock: &block->lock);
230
231 if (data & SCH311X_GPIO_CONF_DIR)
232 return GPIO_LINE_DIRECTION_IN;
233
234 return GPIO_LINE_DIRECTION_OUT;
235}
236
237static int sch311x_gpio_set_config(struct gpio_chip *chip, unsigned offset,
238 unsigned long config)
239{
240 struct sch311x_gpio_block *block = gpiochip_get_data(gc: chip);
241 enum pin_config_param param = pinconf_to_config_param(config);
242 u8 data;
243
244 switch (param) {
245 case PIN_CONFIG_DRIVE_OPEN_DRAIN:
246 spin_lock(lock: &block->lock);
247 data = inb(port: block->runtime_reg + block->config_regs[offset]);
248 data |= SCH311X_GPIO_CONF_OPEN_DRAIN;
249 outb(value: data, port: block->runtime_reg + block->config_regs[offset]);
250 spin_unlock(lock: &block->lock);
251 return 0;
252 case PIN_CONFIG_DRIVE_PUSH_PULL:
253 spin_lock(lock: &block->lock);
254 data = inb(port: block->runtime_reg + block->config_regs[offset]);
255 data &= ~SCH311X_GPIO_CONF_OPEN_DRAIN;
256 outb(value: data, port: block->runtime_reg + block->config_regs[offset]);
257 spin_unlock(lock: &block->lock);
258 return 0;
259 default:
260 break;
261 }
262 return -ENOTSUPP;
263}
264
265static int sch311x_gpio_probe(struct platform_device *pdev)
266{
267 struct sch311x_pdev_data *pdata = dev_get_platdata(dev: &pdev->dev);
268 struct sch311x_gpio_priv *priv;
269 struct sch311x_gpio_block *block;
270 int err, i;
271
272 /* we can register all GPIO data registers at once */
273 if (!devm_request_region(&pdev->dev, pdata->runtime_reg + GP1, 6,
274 DRV_NAME)) {
275 dev_err(&pdev->dev, "Failed to request region 0x%04x-0x%04x.\n",
276 pdata->runtime_reg + GP1, pdata->runtime_reg + GP1 + 5);
277 return -EBUSY;
278 }
279
280 priv = devm_kzalloc(dev: &pdev->dev, size: sizeof(*priv), GFP_KERNEL);
281 if (!priv)
282 return -ENOMEM;
283
284 for (i = 0; i < ARRAY_SIZE(priv->blocks); i++) {
285 block = &priv->blocks[i];
286
287 spin_lock_init(&block->lock);
288
289 block->chip.label = DRV_NAME;
290 block->chip.owner = THIS_MODULE;
291 block->chip.request = sch311x_gpio_request;
292 block->chip.free = sch311x_gpio_free;
293 block->chip.direction_input = sch311x_gpio_direction_in;
294 block->chip.direction_output = sch311x_gpio_direction_out;
295 block->chip.get_direction = sch311x_gpio_get_direction;
296 block->chip.set_config = sch311x_gpio_set_config;
297 block->chip.get = sch311x_gpio_get;
298 block->chip.set = sch311x_gpio_set;
299 block->chip.ngpio = 8;
300 block->chip.parent = &pdev->dev;
301 block->chip.base = sch311x_gpio_blocks[i].base;
302 block->config_regs = sch311x_gpio_blocks[i].config_regs;
303 block->data_reg = sch311x_gpio_blocks[i].data_reg;
304 block->runtime_reg = pdata->runtime_reg;
305
306 err = devm_gpiochip_add_data(&pdev->dev, &block->chip, block);
307 if (err < 0) {
308 dev_err(&pdev->dev,
309 "Could not register gpiochip, %d\n", err);
310 return err;
311 }
312 dev_info(&pdev->dev,
313 "SMSC SCH311x GPIO block %d registered.\n", i);
314 }
315
316 return 0;
317}
318
319static struct platform_driver sch311x_gpio_driver = {
320 .driver.name = DRV_NAME,
321 .probe = sch311x_gpio_probe,
322};
323
324
325/*
326 * Init & exit routines
327 */
328
329static int __init sch311x_detect(int sio_config_port, unsigned short *addr)
330{
331 int err = 0, reg;
332 unsigned short base_addr;
333 u8 dev_id;
334
335 err = sch311x_sio_enter(sio_config_port);
336 if (err)
337 return err;
338
339 /* Check device ID. */
340 reg = sch311x_sio_inb(sio_config_port, reg: 0x20);
341 switch (reg) {
342 case 0x7c: /* SCH3112 */
343 dev_id = 2;
344 break;
345 case 0x7d: /* SCH3114 */
346 dev_id = 4;
347 break;
348 case 0x7f: /* SCH3116 */
349 dev_id = 6;
350 break;
351 default:
352 err = -ENODEV;
353 goto exit;
354 }
355
356 /* Select logical device A (runtime registers) */
357 sch311x_sio_outb(sio_config_port, reg: 0x07, val: 0x0a);
358
359 /* Check if Logical Device Register is currently active */
360 if ((sch311x_sio_inb(sio_config_port, reg: 0x30) & 0x01) == 0)
361 pr_info("Seems that LDN 0x0a is not active...\n");
362
363 /* Get the base address of the runtime registers */
364 base_addr = (sch311x_sio_inb(sio_config_port, reg: 0x60) << 8) |
365 sch311x_sio_inb(sio_config_port, reg: 0x61);
366 if (!base_addr) {
367 pr_err("Base address not set\n");
368 err = -ENODEV;
369 goto exit;
370 }
371 *addr = base_addr;
372
373 pr_info("Found an SMSC SCH311%d chip at 0x%04x\n", dev_id, base_addr);
374
375exit:
376 sch311x_sio_exit(sio_config_port);
377 return err;
378}
379
380static int __init sch311x_gpio_pdev_add(const unsigned short addr)
381{
382 struct sch311x_pdev_data pdata;
383 int err;
384
385 pdata.runtime_reg = addr;
386
387 sch311x_gpio_pdev = platform_device_alloc(DRV_NAME, id: -1);
388 if (!sch311x_gpio_pdev)
389 return -ENOMEM;
390
391 err = platform_device_add_data(pdev: sch311x_gpio_pdev,
392 data: &pdata, size: sizeof(pdata));
393 if (err) {
394 pr_err(DRV_NAME "Platform data allocation failed\n");
395 goto err;
396 }
397
398 err = platform_device_add(pdev: sch311x_gpio_pdev);
399 if (err) {
400 pr_err(DRV_NAME "Device addition failed\n");
401 goto err;
402 }
403 return 0;
404
405err:
406 platform_device_put(pdev: sch311x_gpio_pdev);
407 return err;
408}
409
410static int __init sch311x_gpio_init(void)
411{
412 int err, i;
413 unsigned short addr = 0;
414
415 for (i = 0; i < ARRAY_SIZE(sch311x_ioports); i++)
416 if (sch311x_detect(sio_config_port: sch311x_ioports[i], addr: &addr) == 0)
417 break;
418
419 if (!addr)
420 return -ENODEV;
421
422 err = platform_driver_register(&sch311x_gpio_driver);
423 if (err)
424 return err;
425
426 err = sch311x_gpio_pdev_add(addr);
427 if (err)
428 goto unreg_platform_driver;
429
430 return 0;
431
432unreg_platform_driver:
433 platform_driver_unregister(&sch311x_gpio_driver);
434 return err;
435}
436
437static void __exit sch311x_gpio_exit(void)
438{
439 platform_device_unregister(sch311x_gpio_pdev);
440 platform_driver_unregister(&sch311x_gpio_driver);
441}
442
443module_init(sch311x_gpio_init);
444module_exit(sch311x_gpio_exit);
445
446MODULE_AUTHOR("Bruno Randolf <br1@einfach.org>");
447MODULE_DESCRIPTION("SMSC SCH311x GPIO Driver");
448MODULE_LICENSE("GPL");
449MODULE_ALIAS("platform:gpio-sch311x");
450

source code of linux/drivers/gpio/gpio-sch311x.c