1// SPDX-License-Identifier: GPL-2.0+
2/*
3 * Nano River Technologies viperboard GPIO lib driver
4 *
5 * (C) 2012 by Lemonage GmbH
6 * Author: Lars Poeschel <poeschel@lemonage.de>
7 * All rights reserved.
8 */
9
10#include <linux/kernel.h>
11#include <linux/errno.h>
12#include <linux/module.h>
13#include <linux/slab.h>
14#include <linux/types.h>
15#include <linux/mutex.h>
16#include <linux/platform_device.h>
17#include <linux/usb.h>
18#include <linux/gpio/driver.h>
19
20#include <linux/mfd/viperboard.h>
21
22#define VPRBRD_GPIOA_CLK_1MHZ 0
23#define VPRBRD_GPIOA_CLK_100KHZ 1
24#define VPRBRD_GPIOA_CLK_10KHZ 2
25#define VPRBRD_GPIOA_CLK_1KHZ 3
26#define VPRBRD_GPIOA_CLK_100HZ 4
27#define VPRBRD_GPIOA_CLK_10HZ 5
28
29#define VPRBRD_GPIOA_FREQ_DEFAULT 1000
30
31#define VPRBRD_GPIOA_CMD_CONT 0x00
32#define VPRBRD_GPIOA_CMD_PULSE 0x01
33#define VPRBRD_GPIOA_CMD_PWM 0x02
34#define VPRBRD_GPIOA_CMD_SETOUT 0x03
35#define VPRBRD_GPIOA_CMD_SETIN 0x04
36#define VPRBRD_GPIOA_CMD_SETINT 0x05
37#define VPRBRD_GPIOA_CMD_GETIN 0x06
38
39#define VPRBRD_GPIOB_CMD_SETDIR 0x00
40#define VPRBRD_GPIOB_CMD_SETVAL 0x01
41
42struct vprbrd_gpioa_msg {
43 u8 cmd;
44 u8 clk;
45 u8 offset;
46 u8 t1;
47 u8 t2;
48 u8 invert;
49 u8 pwmlevel;
50 u8 outval;
51 u8 risefall;
52 u8 answer;
53 u8 __fill;
54} __packed;
55
56struct vprbrd_gpiob_msg {
57 u8 cmd;
58 u16 val;
59 u16 mask;
60} __packed;
61
62struct vprbrd_gpio {
63 struct gpio_chip gpioa; /* gpio a related things */
64 u32 gpioa_out;
65 u32 gpioa_val;
66 struct gpio_chip gpiob; /* gpio b related things */
67 u32 gpiob_out;
68 u32 gpiob_val;
69 struct vprbrd *vb;
70};
71
72/* gpioa sampling clock module parameter */
73static unsigned char gpioa_clk;
74static unsigned int gpioa_freq = VPRBRD_GPIOA_FREQ_DEFAULT;
75module_param(gpioa_freq, uint, 0);
76MODULE_PARM_DESC(gpioa_freq,
77 "gpio-a sampling freq in Hz (default is 1000Hz) valid values: 10, 100, 1000, 10000, 100000, 1000000");
78
79/* ----- begin of gipo a chip -------------------------------------------- */
80
81static int vprbrd_gpioa_get(struct gpio_chip *chip,
82 unsigned offset)
83{
84 int ret, answer, error = 0;
85 struct vprbrd_gpio *gpio = gpiochip_get_data(chip);
86 struct vprbrd *vb = gpio->vb;
87 struct vprbrd_gpioa_msg *gamsg = (struct vprbrd_gpioa_msg *)vb->buf;
88
89 /* if io is set to output, just return the saved value */
90 if (gpio->gpioa_out & (1 << offset))
91 return !!(gpio->gpioa_val & (1 << offset));
92
93 mutex_lock(&vb->lock);
94
95 gamsg->cmd = VPRBRD_GPIOA_CMD_GETIN;
96 gamsg->clk = 0x00;
97 gamsg->offset = offset;
98 gamsg->t1 = 0x00;
99 gamsg->t2 = 0x00;
100 gamsg->invert = 0x00;
101 gamsg->pwmlevel = 0x00;
102 gamsg->outval = 0x00;
103 gamsg->risefall = 0x00;
104 gamsg->answer = 0x00;
105 gamsg->__fill = 0x00;
106
107 ret = usb_control_msg(vb->usb_dev, usb_sndctrlpipe(vb->usb_dev, 0),
108 VPRBRD_USB_REQUEST_GPIOA, VPRBRD_USB_TYPE_OUT, 0x0000,
109 0x0000, gamsg, sizeof(struct vprbrd_gpioa_msg),
110 VPRBRD_USB_TIMEOUT_MS);
111 if (ret != sizeof(struct vprbrd_gpioa_msg))
112 error = -EREMOTEIO;
113
114 ret = usb_control_msg(vb->usb_dev, usb_rcvctrlpipe(vb->usb_dev, 0),
115 VPRBRD_USB_REQUEST_GPIOA, VPRBRD_USB_TYPE_IN, 0x0000,
116 0x0000, gamsg, sizeof(struct vprbrd_gpioa_msg),
117 VPRBRD_USB_TIMEOUT_MS);
118 answer = gamsg->answer & 0x01;
119
120 mutex_unlock(&vb->lock);
121
122 if (ret != sizeof(struct vprbrd_gpioa_msg))
123 error = -EREMOTEIO;
124
125 if (error)
126 return error;
127
128 return answer;
129}
130
131static void vprbrd_gpioa_set(struct gpio_chip *chip,
132 unsigned offset, int value)
133{
134 int ret;
135 struct vprbrd_gpio *gpio = gpiochip_get_data(chip);
136 struct vprbrd *vb = gpio->vb;
137 struct vprbrd_gpioa_msg *gamsg = (struct vprbrd_gpioa_msg *)vb->buf;
138
139 if (gpio->gpioa_out & (1 << offset)) {
140 if (value)
141 gpio->gpioa_val |= (1 << offset);
142 else
143 gpio->gpioa_val &= ~(1 << offset);
144
145 mutex_lock(&vb->lock);
146
147 gamsg->cmd = VPRBRD_GPIOA_CMD_SETOUT;
148 gamsg->clk = 0x00;
149 gamsg->offset = offset;
150 gamsg->t1 = 0x00;
151 gamsg->t2 = 0x00;
152 gamsg->invert = 0x00;
153 gamsg->pwmlevel = 0x00;
154 gamsg->outval = value;
155 gamsg->risefall = 0x00;
156 gamsg->answer = 0x00;
157 gamsg->__fill = 0x00;
158
159 ret = usb_control_msg(vb->usb_dev,
160 usb_sndctrlpipe(vb->usb_dev, 0),
161 VPRBRD_USB_REQUEST_GPIOA, VPRBRD_USB_TYPE_OUT,
162 0x0000, 0x0000, gamsg,
163 sizeof(struct vprbrd_gpioa_msg), VPRBRD_USB_TIMEOUT_MS);
164
165 mutex_unlock(&vb->lock);
166
167 if (ret != sizeof(struct vprbrd_gpioa_msg))
168 dev_err(chip->parent, "usb error setting pin value\n");
169 }
170}
171
172static int vprbrd_gpioa_direction_input(struct gpio_chip *chip,
173 unsigned offset)
174{
175 int ret;
176 struct vprbrd_gpio *gpio = gpiochip_get_data(chip);
177 struct vprbrd *vb = gpio->vb;
178 struct vprbrd_gpioa_msg *gamsg = (struct vprbrd_gpioa_msg *)vb->buf;
179
180 gpio->gpioa_out &= ~(1 << offset);
181
182 mutex_lock(&vb->lock);
183
184 gamsg->cmd = VPRBRD_GPIOA_CMD_SETIN;
185 gamsg->clk = gpioa_clk;
186 gamsg->offset = offset;
187 gamsg->t1 = 0x00;
188 gamsg->t2 = 0x00;
189 gamsg->invert = 0x00;
190 gamsg->pwmlevel = 0x00;
191 gamsg->outval = 0x00;
192 gamsg->risefall = 0x00;
193 gamsg->answer = 0x00;
194 gamsg->__fill = 0x00;
195
196 ret = usb_control_msg(vb->usb_dev, usb_sndctrlpipe(vb->usb_dev, 0),
197 VPRBRD_USB_REQUEST_GPIOA, VPRBRD_USB_TYPE_OUT, 0x0000,
198 0x0000, gamsg, sizeof(struct vprbrd_gpioa_msg),
199 VPRBRD_USB_TIMEOUT_MS);
200
201 mutex_unlock(&vb->lock);
202
203 if (ret != sizeof(struct vprbrd_gpioa_msg))
204 return -EREMOTEIO;
205
206 return 0;
207}
208
209static int vprbrd_gpioa_direction_output(struct gpio_chip *chip,
210 unsigned offset, int value)
211{
212 int ret;
213 struct vprbrd_gpio *gpio = gpiochip_get_data(chip);
214 struct vprbrd *vb = gpio->vb;
215 struct vprbrd_gpioa_msg *gamsg = (struct vprbrd_gpioa_msg *)vb->buf;
216
217 gpio->gpioa_out |= (1 << offset);
218 if (value)
219 gpio->gpioa_val |= (1 << offset);
220 else
221 gpio->gpioa_val &= ~(1 << offset);
222
223 mutex_lock(&vb->lock);
224
225 gamsg->cmd = VPRBRD_GPIOA_CMD_SETOUT;
226 gamsg->clk = 0x00;
227 gamsg->offset = offset;
228 gamsg->t1 = 0x00;
229 gamsg->t2 = 0x00;
230 gamsg->invert = 0x00;
231 gamsg->pwmlevel = 0x00;
232 gamsg->outval = value;
233 gamsg->risefall = 0x00;
234 gamsg->answer = 0x00;
235 gamsg->__fill = 0x00;
236
237 ret = usb_control_msg(vb->usb_dev, usb_sndctrlpipe(vb->usb_dev, 0),
238 VPRBRD_USB_REQUEST_GPIOA, VPRBRD_USB_TYPE_OUT, 0x0000,
239 0x0000, gamsg, sizeof(struct vprbrd_gpioa_msg),
240 VPRBRD_USB_TIMEOUT_MS);
241
242 mutex_unlock(&vb->lock);
243
244 if (ret != sizeof(struct vprbrd_gpioa_msg))
245 return -EREMOTEIO;
246
247 return 0;
248}
249
250/* ----- end of gpio a chip ---------------------------------------------- */
251
252/* ----- begin of gipo b chip -------------------------------------------- */
253
254static int vprbrd_gpiob_setdir(struct vprbrd *vb, unsigned offset,
255 unsigned dir)
256{
257 struct vprbrd_gpiob_msg *gbmsg = (struct vprbrd_gpiob_msg *)vb->buf;
258 int ret;
259
260 gbmsg->cmd = VPRBRD_GPIOB_CMD_SETDIR;
261 gbmsg->val = cpu_to_be16(dir << offset);
262 gbmsg->mask = cpu_to_be16(0x0001 << offset);
263
264 ret = usb_control_msg(vb->usb_dev, usb_sndctrlpipe(vb->usb_dev, 0),
265 VPRBRD_USB_REQUEST_GPIOB, VPRBRD_USB_TYPE_OUT, 0x0000,
266 0x0000, gbmsg, sizeof(struct vprbrd_gpiob_msg),
267 VPRBRD_USB_TIMEOUT_MS);
268
269 if (ret != sizeof(struct vprbrd_gpiob_msg))
270 return -EREMOTEIO;
271
272 return 0;
273}
274
275static int vprbrd_gpiob_get(struct gpio_chip *chip,
276 unsigned offset)
277{
278 int ret;
279 u16 val;
280 struct vprbrd_gpio *gpio = gpiochip_get_data(chip);
281 struct vprbrd *vb = gpio->vb;
282 struct vprbrd_gpiob_msg *gbmsg = (struct vprbrd_gpiob_msg *)vb->buf;
283
284 /* if io is set to output, just return the saved value */
285 if (gpio->gpiob_out & (1 << offset))
286 return gpio->gpiob_val & (1 << offset);
287
288 mutex_lock(&vb->lock);
289
290 ret = usb_control_msg(vb->usb_dev, usb_rcvctrlpipe(vb->usb_dev, 0),
291 VPRBRD_USB_REQUEST_GPIOB, VPRBRD_USB_TYPE_IN, 0x0000,
292 0x0000, gbmsg, sizeof(struct vprbrd_gpiob_msg),
293 VPRBRD_USB_TIMEOUT_MS);
294 val = gbmsg->val;
295
296 mutex_unlock(&vb->lock);
297
298 if (ret != sizeof(struct vprbrd_gpiob_msg))
299 return ret;
300
301 /* cache the read values */
302 gpio->gpiob_val = be16_to_cpu(val);
303
304 return (gpio->gpiob_val >> offset) & 0x1;
305}
306
307static void vprbrd_gpiob_set(struct gpio_chip *chip,
308 unsigned offset, int value)
309{
310 int ret;
311 struct vprbrd_gpio *gpio = gpiochip_get_data(chip);
312 struct vprbrd *vb = gpio->vb;
313 struct vprbrd_gpiob_msg *gbmsg = (struct vprbrd_gpiob_msg *)vb->buf;
314
315 if (gpio->gpiob_out & (1 << offset)) {
316 if (value)
317 gpio->gpiob_val |= (1 << offset);
318 else
319 gpio->gpiob_val &= ~(1 << offset);
320
321 mutex_lock(&vb->lock);
322
323 gbmsg->cmd = VPRBRD_GPIOB_CMD_SETVAL;
324 gbmsg->val = cpu_to_be16(value << offset);
325 gbmsg->mask = cpu_to_be16(0x0001 << offset);
326
327 ret = usb_control_msg(vb->usb_dev,
328 usb_sndctrlpipe(vb->usb_dev, 0),
329 VPRBRD_USB_REQUEST_GPIOB, VPRBRD_USB_TYPE_OUT,
330 0x0000, 0x0000, gbmsg,
331 sizeof(struct vprbrd_gpiob_msg), VPRBRD_USB_TIMEOUT_MS);
332
333 mutex_unlock(&vb->lock);
334
335 if (ret != sizeof(struct vprbrd_gpiob_msg))
336 dev_err(chip->parent, "usb error setting pin value\n");
337 }
338}
339
340static int vprbrd_gpiob_direction_input(struct gpio_chip *chip,
341 unsigned offset)
342{
343 int ret;
344 struct vprbrd_gpio *gpio = gpiochip_get_data(chip);
345 struct vprbrd *vb = gpio->vb;
346
347 gpio->gpiob_out &= ~(1 << offset);
348
349 mutex_lock(&vb->lock);
350
351 ret = vprbrd_gpiob_setdir(vb, offset, 0);
352
353 mutex_unlock(&vb->lock);
354
355 if (ret)
356 dev_err(chip->parent, "usb error setting pin to input\n");
357
358 return ret;
359}
360
361static int vprbrd_gpiob_direction_output(struct gpio_chip *chip,
362 unsigned offset, int value)
363{
364 int ret;
365 struct vprbrd_gpio *gpio = gpiochip_get_data(chip);
366 struct vprbrd *vb = gpio->vb;
367
368 gpio->gpiob_out |= (1 << offset);
369
370 mutex_lock(&vb->lock);
371
372 ret = vprbrd_gpiob_setdir(vb, offset, 1);
373 if (ret)
374 dev_err(chip->parent, "usb error setting pin to output\n");
375
376 mutex_unlock(&vb->lock);
377
378 vprbrd_gpiob_set(chip, offset, value);
379
380 return ret;
381}
382
383/* ----- end of gpio b chip ---------------------------------------------- */
384
385static int vprbrd_gpio_probe(struct platform_device *pdev)
386{
387 struct vprbrd *vb = dev_get_drvdata(pdev->dev.parent);
388 struct vprbrd_gpio *vb_gpio;
389 int ret;
390
391 vb_gpio = devm_kzalloc(&pdev->dev, sizeof(*vb_gpio), GFP_KERNEL);
392 if (vb_gpio == NULL)
393 return -ENOMEM;
394
395 vb_gpio->vb = vb;
396 /* registering gpio a */
397 vb_gpio->gpioa.label = "viperboard gpio a";
398 vb_gpio->gpioa.parent = &pdev->dev;
399 vb_gpio->gpioa.owner = THIS_MODULE;
400 vb_gpio->gpioa.base = -1;
401 vb_gpio->gpioa.ngpio = 16;
402 vb_gpio->gpioa.can_sleep = true;
403 vb_gpio->gpioa.set = vprbrd_gpioa_set;
404 vb_gpio->gpioa.get = vprbrd_gpioa_get;
405 vb_gpio->gpioa.direction_input = vprbrd_gpioa_direction_input;
406 vb_gpio->gpioa.direction_output = vprbrd_gpioa_direction_output;
407 ret = devm_gpiochip_add_data(&pdev->dev, &vb_gpio->gpioa, vb_gpio);
408 if (ret < 0) {
409 dev_err(vb_gpio->gpioa.parent, "could not add gpio a");
410 return ret;
411 }
412
413 /* registering gpio b */
414 vb_gpio->gpiob.label = "viperboard gpio b";
415 vb_gpio->gpiob.parent = &pdev->dev;
416 vb_gpio->gpiob.owner = THIS_MODULE;
417 vb_gpio->gpiob.base = -1;
418 vb_gpio->gpiob.ngpio = 16;
419 vb_gpio->gpiob.can_sleep = true;
420 vb_gpio->gpiob.set = vprbrd_gpiob_set;
421 vb_gpio->gpiob.get = vprbrd_gpiob_get;
422 vb_gpio->gpiob.direction_input = vprbrd_gpiob_direction_input;
423 vb_gpio->gpiob.direction_output = vprbrd_gpiob_direction_output;
424 ret = devm_gpiochip_add_data(&pdev->dev, &vb_gpio->gpiob, vb_gpio);
425 if (ret < 0) {
426 dev_err(vb_gpio->gpiob.parent, "could not add gpio b");
427 return ret;
428 }
429
430 platform_set_drvdata(pdev, vb_gpio);
431
432 return ret;
433}
434
435static struct platform_driver vprbrd_gpio_driver = {
436 .driver.name = "viperboard-gpio",
437 .probe = vprbrd_gpio_probe,
438};
439
440static int __init vprbrd_gpio_init(void)
441{
442 switch (gpioa_freq) {
443 case 1000000:
444 gpioa_clk = VPRBRD_GPIOA_CLK_1MHZ;
445 break;
446 case 100000:
447 gpioa_clk = VPRBRD_GPIOA_CLK_100KHZ;
448 break;
449 case 10000:
450 gpioa_clk = VPRBRD_GPIOA_CLK_10KHZ;
451 break;
452 case 1000:
453 gpioa_clk = VPRBRD_GPIOA_CLK_1KHZ;
454 break;
455 case 100:
456 gpioa_clk = VPRBRD_GPIOA_CLK_100HZ;
457 break;
458 case 10:
459 gpioa_clk = VPRBRD_GPIOA_CLK_10HZ;
460 break;
461 default:
462 pr_warn("invalid gpioa_freq (%d)\n", gpioa_freq);
463 gpioa_clk = VPRBRD_GPIOA_CLK_1KHZ;
464 }
465
466 return platform_driver_register(&vprbrd_gpio_driver);
467}
468subsys_initcall(vprbrd_gpio_init);
469
470static void __exit vprbrd_gpio_exit(void)
471{
472 platform_driver_unregister(&vprbrd_gpio_driver);
473}
474module_exit(vprbrd_gpio_exit);
475
476MODULE_AUTHOR("Lars Poeschel <poeschel@lemonage.de>");
477MODULE_DESCRIPTION("GPIO driver for Nano River Techs Viperboard");
478MODULE_LICENSE("GPL");
479MODULE_ALIAS("platform:viperboard-gpio");
480