1 /*
2 * Nano River Technologies viperboard GPIO lib driver
3 *
4 * (C) 2012 by Lemonage GmbH
5 * Author: Lars Poeschel <poeschel@lemonage.de>
6 * All rights reserved.
7 *
8 * This program is free software; you can redistribute it and/or modify it
9 * under the terms of the GNU General Public License as published by the
10 * Free Software Foundation; either version 2 of the License, or (at your
11 * option) any later version.
12 *
13 */
14
15 #include <linux/kernel.h>
16 #include <linux/errno.h>
17 #include <linux/module.h>
18 #include <linux/slab.h>
19 #include <linux/types.h>
20 #include <linux/mutex.h>
21 #include <linux/platform_device.h>
22
23 #include <linux/usb.h>
24 #include <linux/gpio.h>
25
26 #include <linux/mfd/viperboard.h>
27
28 #define VPRBRD_GPIOA_CLK_1MHZ 0
29 #define VPRBRD_GPIOA_CLK_100KHZ 1
30 #define VPRBRD_GPIOA_CLK_10KHZ 2
31 #define VPRBRD_GPIOA_CLK_1KHZ 3
32 #define VPRBRD_GPIOA_CLK_100HZ 4
33 #define VPRBRD_GPIOA_CLK_10HZ 5
34
35 #define VPRBRD_GPIOA_FREQ_DEFAULT 1000
36
37 #define VPRBRD_GPIOA_CMD_CONT 0x00
38 #define VPRBRD_GPIOA_CMD_PULSE 0x01
39 #define VPRBRD_GPIOA_CMD_PWM 0x02
40 #define VPRBRD_GPIOA_CMD_SETOUT 0x03
41 #define VPRBRD_GPIOA_CMD_SETIN 0x04
42 #define VPRBRD_GPIOA_CMD_SETINT 0x05
43 #define VPRBRD_GPIOA_CMD_GETIN 0x06
44
45 #define VPRBRD_GPIOB_CMD_SETDIR 0x00
46 #define VPRBRD_GPIOB_CMD_SETVAL 0x01
47
48 struct vprbrd_gpioa_msg {
49 u8 cmd;
50 u8 clk;
51 u8 offset;
52 u8 t1;
53 u8 t2;
54 u8 invert;
55 u8 pwmlevel;
56 u8 outval;
57 u8 risefall;
58 u8 answer;
59 u8 __fill;
60 } __packed;
61
62 struct vprbrd_gpiob_msg {
63 u8 cmd;
64 u16 val;
65 u16 mask;
66 } __packed;
67
68 struct vprbrd_gpio {
69 struct gpio_chip gpioa; /* gpio a related things */
70 u32 gpioa_out;
71 u32 gpioa_val;
72 struct gpio_chip gpiob; /* gpio b related things */
73 u32 gpiob_out;
74 u32 gpiob_val;
75 struct vprbrd *vb;
76 };
77
78 /* gpioa sampling clock module parameter */
79 static unsigned char gpioa_clk;
80 static unsigned int gpioa_freq = VPRBRD_GPIOA_FREQ_DEFAULT;
81 module_param(gpioa_freq, uint, 0);
82 MODULE_PARM_DESC(gpioa_freq,
83 "gpio-a sampling freq in Hz (default is 1000Hz) valid values: 10, 100, 1000, 10000, 100000, 1000000");
84
85 /* ----- begin of gipo a chip -------------------------------------------- */
86
vprbrd_gpioa_get(struct gpio_chip * chip,unsigned offset)87 static int vprbrd_gpioa_get(struct gpio_chip *chip,
88 unsigned offset)
89 {
90 int ret, answer, error = 0;
91 struct vprbrd_gpio *gpio =
92 container_of(chip, struct vprbrd_gpio, gpioa);
93 struct vprbrd *vb = gpio->vb;
94 struct vprbrd_gpioa_msg *gamsg = (struct vprbrd_gpioa_msg *)vb->buf;
95
96 /* if io is set to output, just return the saved value */
97 if (gpio->gpioa_out & (1 << offset))
98 return gpio->gpioa_val & (1 << offset);
99
100 mutex_lock(&vb->lock);
101
102 gamsg->cmd = VPRBRD_GPIOA_CMD_GETIN;
103 gamsg->clk = 0x00;
104 gamsg->offset = offset;
105 gamsg->t1 = 0x00;
106 gamsg->t2 = 0x00;
107 gamsg->invert = 0x00;
108 gamsg->pwmlevel = 0x00;
109 gamsg->outval = 0x00;
110 gamsg->risefall = 0x00;
111 gamsg->answer = 0x00;
112 gamsg->__fill = 0x00;
113
114 ret = usb_control_msg(vb->usb_dev, usb_sndctrlpipe(vb->usb_dev, 0),
115 VPRBRD_USB_REQUEST_GPIOA, VPRBRD_USB_TYPE_OUT, 0x0000,
116 0x0000, gamsg, sizeof(struct vprbrd_gpioa_msg),
117 VPRBRD_USB_TIMEOUT_MS);
118 if (ret != sizeof(struct vprbrd_gpioa_msg))
119 error = -EREMOTEIO;
120
121 ret = usb_control_msg(vb->usb_dev, usb_rcvctrlpipe(vb->usb_dev, 0),
122 VPRBRD_USB_REQUEST_GPIOA, VPRBRD_USB_TYPE_IN, 0x0000,
123 0x0000, gamsg, sizeof(struct vprbrd_gpioa_msg),
124 VPRBRD_USB_TIMEOUT_MS);
125 answer = gamsg->answer & 0x01;
126
127 mutex_unlock(&vb->lock);
128
129 if (ret != sizeof(struct vprbrd_gpioa_msg))
130 error = -EREMOTEIO;
131
132 if (error)
133 return error;
134
135 return answer;
136 }
137
vprbrd_gpioa_set(struct gpio_chip * chip,unsigned offset,int value)138 static void vprbrd_gpioa_set(struct gpio_chip *chip,
139 unsigned offset, int value)
140 {
141 int ret;
142 struct vprbrd_gpio *gpio =
143 container_of(chip, struct vprbrd_gpio, gpioa);
144 struct vprbrd *vb = gpio->vb;
145 struct vprbrd_gpioa_msg *gamsg = (struct vprbrd_gpioa_msg *)vb->buf;
146
147 if (gpio->gpioa_out & (1 << offset)) {
148 if (value)
149 gpio->gpioa_val |= (1 << offset);
150 else
151 gpio->gpioa_val &= ~(1 << offset);
152
153 mutex_lock(&vb->lock);
154
155 gamsg->cmd = VPRBRD_GPIOA_CMD_SETOUT;
156 gamsg->clk = 0x00;
157 gamsg->offset = offset;
158 gamsg->t1 = 0x00;
159 gamsg->t2 = 0x00;
160 gamsg->invert = 0x00;
161 gamsg->pwmlevel = 0x00;
162 gamsg->outval = value;
163 gamsg->risefall = 0x00;
164 gamsg->answer = 0x00;
165 gamsg->__fill = 0x00;
166
167 ret = usb_control_msg(vb->usb_dev,
168 usb_sndctrlpipe(vb->usb_dev, 0),
169 VPRBRD_USB_REQUEST_GPIOA, VPRBRD_USB_TYPE_OUT,
170 0x0000, 0x0000, gamsg,
171 sizeof(struct vprbrd_gpioa_msg), VPRBRD_USB_TIMEOUT_MS);
172
173 mutex_unlock(&vb->lock);
174
175 if (ret != sizeof(struct vprbrd_gpioa_msg))
176 dev_err(chip->dev, "usb error setting pin value\n");
177 }
178 }
179
vprbrd_gpioa_direction_input(struct gpio_chip * chip,unsigned offset)180 static int vprbrd_gpioa_direction_input(struct gpio_chip *chip,
181 unsigned offset)
182 {
183 int ret;
184 struct vprbrd_gpio *gpio =
185 container_of(chip, struct vprbrd_gpio, gpioa);
186 struct vprbrd *vb = gpio->vb;
187 struct vprbrd_gpioa_msg *gamsg = (struct vprbrd_gpioa_msg *)vb->buf;
188
189 gpio->gpioa_out &= ~(1 << offset);
190
191 mutex_lock(&vb->lock);
192
193 gamsg->cmd = VPRBRD_GPIOA_CMD_SETIN;
194 gamsg->clk = gpioa_clk;
195 gamsg->offset = offset;
196 gamsg->t1 = 0x00;
197 gamsg->t2 = 0x00;
198 gamsg->invert = 0x00;
199 gamsg->pwmlevel = 0x00;
200 gamsg->outval = 0x00;
201 gamsg->risefall = 0x00;
202 gamsg->answer = 0x00;
203 gamsg->__fill = 0x00;
204
205 ret = usb_control_msg(vb->usb_dev, usb_sndctrlpipe(vb->usb_dev, 0),
206 VPRBRD_USB_REQUEST_GPIOA, VPRBRD_USB_TYPE_OUT, 0x0000,
207 0x0000, gamsg, sizeof(struct vprbrd_gpioa_msg),
208 VPRBRD_USB_TIMEOUT_MS);
209
210 mutex_unlock(&vb->lock);
211
212 if (ret != sizeof(struct vprbrd_gpioa_msg))
213 return -EREMOTEIO;
214
215 return 0;
216 }
217
vprbrd_gpioa_direction_output(struct gpio_chip * chip,unsigned offset,int value)218 static int vprbrd_gpioa_direction_output(struct gpio_chip *chip,
219 unsigned offset, int value)
220 {
221 int ret;
222 struct vprbrd_gpio *gpio =
223 container_of(chip, struct vprbrd_gpio, gpioa);
224 struct vprbrd *vb = gpio->vb;
225 struct vprbrd_gpioa_msg *gamsg = (struct vprbrd_gpioa_msg *)vb->buf;
226
227 gpio->gpioa_out |= (1 << offset);
228 if (value)
229 gpio->gpioa_val |= (1 << offset);
230 else
231 gpio->gpioa_val &= ~(1 << offset);
232
233 mutex_lock(&vb->lock);
234
235 gamsg->cmd = VPRBRD_GPIOA_CMD_SETOUT;
236 gamsg->clk = 0x00;
237 gamsg->offset = offset;
238 gamsg->t1 = 0x00;
239 gamsg->t2 = 0x00;
240 gamsg->invert = 0x00;
241 gamsg->pwmlevel = 0x00;
242 gamsg->outval = value;
243 gamsg->risefall = 0x00;
244 gamsg->answer = 0x00;
245 gamsg->__fill = 0x00;
246
247 ret = usb_control_msg(vb->usb_dev, usb_sndctrlpipe(vb->usb_dev, 0),
248 VPRBRD_USB_REQUEST_GPIOA, VPRBRD_USB_TYPE_OUT, 0x0000,
249 0x0000, gamsg, sizeof(struct vprbrd_gpioa_msg),
250 VPRBRD_USB_TIMEOUT_MS);
251
252 mutex_unlock(&vb->lock);
253
254 if (ret != sizeof(struct vprbrd_gpioa_msg))
255 return -EREMOTEIO;
256
257 return 0;
258 }
259
260 /* ----- end of gpio a chip ---------------------------------------------- */
261
262 /* ----- begin of gipo b chip -------------------------------------------- */
263
vprbrd_gpiob_setdir(struct vprbrd * vb,unsigned offset,unsigned dir)264 static int vprbrd_gpiob_setdir(struct vprbrd *vb, unsigned offset,
265 unsigned dir)
266 {
267 struct vprbrd_gpiob_msg *gbmsg = (struct vprbrd_gpiob_msg *)vb->buf;
268 int ret;
269
270 gbmsg->cmd = VPRBRD_GPIOB_CMD_SETDIR;
271 gbmsg->val = cpu_to_be16(dir << offset);
272 gbmsg->mask = cpu_to_be16(0x0001 << offset);
273
274 ret = usb_control_msg(vb->usb_dev, usb_sndctrlpipe(vb->usb_dev, 0),
275 VPRBRD_USB_REQUEST_GPIOB, VPRBRD_USB_TYPE_OUT, 0x0000,
276 0x0000, gbmsg, sizeof(struct vprbrd_gpiob_msg),
277 VPRBRD_USB_TIMEOUT_MS);
278
279 if (ret != sizeof(struct vprbrd_gpiob_msg))
280 return -EREMOTEIO;
281
282 return 0;
283 }
284
vprbrd_gpiob_get(struct gpio_chip * chip,unsigned offset)285 static int vprbrd_gpiob_get(struct gpio_chip *chip,
286 unsigned offset)
287 {
288 int ret;
289 u16 val;
290 struct vprbrd_gpio *gpio =
291 container_of(chip, struct vprbrd_gpio, gpiob);
292 struct vprbrd *vb = gpio->vb;
293 struct vprbrd_gpiob_msg *gbmsg = (struct vprbrd_gpiob_msg *)vb->buf;
294
295 /* if io is set to output, just return the saved value */
296 if (gpio->gpiob_out & (1 << offset))
297 return gpio->gpiob_val & (1 << offset);
298
299 mutex_lock(&vb->lock);
300
301 ret = usb_control_msg(vb->usb_dev, usb_rcvctrlpipe(vb->usb_dev, 0),
302 VPRBRD_USB_REQUEST_GPIOB, VPRBRD_USB_TYPE_IN, 0x0000,
303 0x0000, gbmsg, sizeof(struct vprbrd_gpiob_msg),
304 VPRBRD_USB_TIMEOUT_MS);
305 val = gbmsg->val;
306
307 mutex_unlock(&vb->lock);
308
309 if (ret != sizeof(struct vprbrd_gpiob_msg))
310 return ret;
311
312 /* cache the read values */
313 gpio->gpiob_val = be16_to_cpu(val);
314
315 return (gpio->gpiob_val >> offset) & 0x1;
316 }
317
vprbrd_gpiob_set(struct gpio_chip * chip,unsigned offset,int value)318 static void vprbrd_gpiob_set(struct gpio_chip *chip,
319 unsigned offset, int value)
320 {
321 int ret;
322 struct vprbrd_gpio *gpio =
323 container_of(chip, struct vprbrd_gpio, gpiob);
324 struct vprbrd *vb = gpio->vb;
325 struct vprbrd_gpiob_msg *gbmsg = (struct vprbrd_gpiob_msg *)vb->buf;
326
327 if (gpio->gpiob_out & (1 << offset)) {
328 if (value)
329 gpio->gpiob_val |= (1 << offset);
330 else
331 gpio->gpiob_val &= ~(1 << offset);
332
333 mutex_lock(&vb->lock);
334
335 gbmsg->cmd = VPRBRD_GPIOB_CMD_SETVAL;
336 gbmsg->val = cpu_to_be16(value << offset);
337 gbmsg->mask = cpu_to_be16(0x0001 << offset);
338
339 ret = usb_control_msg(vb->usb_dev,
340 usb_sndctrlpipe(vb->usb_dev, 0),
341 VPRBRD_USB_REQUEST_GPIOB, VPRBRD_USB_TYPE_OUT,
342 0x0000, 0x0000, gbmsg,
343 sizeof(struct vprbrd_gpiob_msg), VPRBRD_USB_TIMEOUT_MS);
344
345 mutex_unlock(&vb->lock);
346
347 if (ret != sizeof(struct vprbrd_gpiob_msg))
348 dev_err(chip->dev, "usb error setting pin value\n");
349 }
350 }
351
vprbrd_gpiob_direction_input(struct gpio_chip * chip,unsigned offset)352 static int vprbrd_gpiob_direction_input(struct gpio_chip *chip,
353 unsigned offset)
354 {
355 int ret;
356 struct vprbrd_gpio *gpio =
357 container_of(chip, struct vprbrd_gpio, gpiob);
358 struct vprbrd *vb = gpio->vb;
359
360 gpio->gpiob_out &= ~(1 << offset);
361
362 mutex_lock(&vb->lock);
363
364 ret = vprbrd_gpiob_setdir(vb, offset, 0);
365
366 mutex_unlock(&vb->lock);
367
368 if (ret)
369 dev_err(chip->dev, "usb error setting pin to input\n");
370
371 return ret;
372 }
373
vprbrd_gpiob_direction_output(struct gpio_chip * chip,unsigned offset,int value)374 static int vprbrd_gpiob_direction_output(struct gpio_chip *chip,
375 unsigned offset, int value)
376 {
377 int ret;
378 struct vprbrd_gpio *gpio =
379 container_of(chip, struct vprbrd_gpio, gpiob);
380 struct vprbrd *vb = gpio->vb;
381
382 gpio->gpiob_out |= (1 << offset);
383
384 mutex_lock(&vb->lock);
385
386 ret = vprbrd_gpiob_setdir(vb, offset, 1);
387 if (ret)
388 dev_err(chip->dev, "usb error setting pin to output\n");
389
390 mutex_unlock(&vb->lock);
391
392 vprbrd_gpiob_set(chip, offset, value);
393
394 return ret;
395 }
396
397 /* ----- end of gpio b chip ---------------------------------------------- */
398
vprbrd_gpio_probe(struct platform_device * pdev)399 static int vprbrd_gpio_probe(struct platform_device *pdev)
400 {
401 struct vprbrd *vb = dev_get_drvdata(pdev->dev.parent);
402 struct vprbrd_gpio *vb_gpio;
403 int ret;
404
405 vb_gpio = devm_kzalloc(&pdev->dev, sizeof(*vb_gpio), GFP_KERNEL);
406 if (vb_gpio == NULL)
407 return -ENOMEM;
408
409 vb_gpio->vb = vb;
410 /* registering gpio a */
411 vb_gpio->gpioa.label = "viperboard gpio a";
412 vb_gpio->gpioa.dev = &pdev->dev;
413 vb_gpio->gpioa.owner = THIS_MODULE;
414 vb_gpio->gpioa.base = -1;
415 vb_gpio->gpioa.ngpio = 16;
416 vb_gpio->gpioa.can_sleep = true;
417 vb_gpio->gpioa.set = vprbrd_gpioa_set;
418 vb_gpio->gpioa.get = vprbrd_gpioa_get;
419 vb_gpio->gpioa.direction_input = vprbrd_gpioa_direction_input;
420 vb_gpio->gpioa.direction_output = vprbrd_gpioa_direction_output;
421 ret = gpiochip_add(&vb_gpio->gpioa);
422 if (ret < 0) {
423 dev_err(vb_gpio->gpioa.dev, "could not add gpio a");
424 goto err_gpioa;
425 }
426
427 /* registering gpio b */
428 vb_gpio->gpiob.label = "viperboard gpio b";
429 vb_gpio->gpiob.dev = &pdev->dev;
430 vb_gpio->gpiob.owner = THIS_MODULE;
431 vb_gpio->gpiob.base = -1;
432 vb_gpio->gpiob.ngpio = 16;
433 vb_gpio->gpiob.can_sleep = true;
434 vb_gpio->gpiob.set = vprbrd_gpiob_set;
435 vb_gpio->gpiob.get = vprbrd_gpiob_get;
436 vb_gpio->gpiob.direction_input = vprbrd_gpiob_direction_input;
437 vb_gpio->gpiob.direction_output = vprbrd_gpiob_direction_output;
438 ret = gpiochip_add(&vb_gpio->gpiob);
439 if (ret < 0) {
440 dev_err(vb_gpio->gpiob.dev, "could not add gpio b");
441 goto err_gpiob;
442 }
443
444 platform_set_drvdata(pdev, vb_gpio);
445
446 return ret;
447
448 err_gpiob:
449 gpiochip_remove(&vb_gpio->gpioa);
450
451 err_gpioa:
452 return ret;
453 }
454
vprbrd_gpio_remove(struct platform_device * pdev)455 static int vprbrd_gpio_remove(struct platform_device *pdev)
456 {
457 struct vprbrd_gpio *vb_gpio = platform_get_drvdata(pdev);
458
459 gpiochip_remove(&vb_gpio->gpiob);
460
461 return 0;
462 }
463
464 static struct platform_driver vprbrd_gpio_driver = {
465 .driver.name = "viperboard-gpio",
466 .driver.owner = THIS_MODULE,
467 .probe = vprbrd_gpio_probe,
468 .remove = vprbrd_gpio_remove,
469 };
470
vprbrd_gpio_init(void)471 static int __init vprbrd_gpio_init(void)
472 {
473 switch (gpioa_freq) {
474 case 1000000:
475 gpioa_clk = VPRBRD_GPIOA_CLK_1MHZ;
476 break;
477 case 100000:
478 gpioa_clk = VPRBRD_GPIOA_CLK_100KHZ;
479 break;
480 case 10000:
481 gpioa_clk = VPRBRD_GPIOA_CLK_10KHZ;
482 break;
483 case 1000:
484 gpioa_clk = VPRBRD_GPIOA_CLK_1KHZ;
485 break;
486 case 100:
487 gpioa_clk = VPRBRD_GPIOA_CLK_100HZ;
488 break;
489 case 10:
490 gpioa_clk = VPRBRD_GPIOA_CLK_10HZ;
491 break;
492 default:
493 pr_warn("invalid gpioa_freq (%d)\n", gpioa_freq);
494 gpioa_clk = VPRBRD_GPIOA_CLK_1KHZ;
495 }
496
497 return platform_driver_register(&vprbrd_gpio_driver);
498 }
499 subsys_initcall(vprbrd_gpio_init);
500
vprbrd_gpio_exit(void)501 static void __exit vprbrd_gpio_exit(void)
502 {
503 platform_driver_unregister(&vprbrd_gpio_driver);
504 }
505 module_exit(vprbrd_gpio_exit);
506
507 MODULE_AUTHOR("Lars Poeschel <poeschel@lemonage.de>");
508 MODULE_DESCRIPTION("GPIO driver for Nano River Techs Viperboard");
509 MODULE_LICENSE("GPL");
510 MODULE_ALIAS("platform:viperboard-gpio");
511