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
42 struct 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
56 struct vprbrd_gpiob_msg {
57 u8 cmd;
58 u16 val;
59 u16 mask;
60 } __packed;
61
62 struct 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 */
73 static unsigned char gpioa_clk;
74 static unsigned int gpioa_freq = VPRBRD_GPIOA_FREQ_DEFAULT;
75 module_param(gpioa_freq, uint, 0);
76 MODULE_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
vprbrd_gpioa_get(struct gpio_chip * chip,unsigned int offset)81 static int vprbrd_gpioa_get(struct gpio_chip *chip,
82 unsigned int 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
vprbrd_gpioa_set(struct gpio_chip * chip,unsigned int offset,int value)131 static int vprbrd_gpioa_set(struct gpio_chip *chip, unsigned int offset,
132 int value)
133 {
134 int ret = 0;
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 return 0;
141
142 if (value)
143 gpio->gpioa_val |= (1 << offset);
144 else
145 gpio->gpioa_val &= ~(1 << offset);
146
147 mutex_lock(&vb->lock);
148
149 gamsg->cmd = VPRBRD_GPIOA_CMD_SETOUT;
150 gamsg->clk = 0x00;
151 gamsg->offset = offset;
152 gamsg->t1 = 0x00;
153 gamsg->t2 = 0x00;
154 gamsg->invert = 0x00;
155 gamsg->pwmlevel = 0x00;
156 gamsg->outval = value;
157 gamsg->risefall = 0x00;
158 gamsg->answer = 0x00;
159 gamsg->__fill = 0x00;
160
161 ret = usb_control_msg(vb->usb_dev, usb_sndctrlpipe(vb->usb_dev, 0),
162 VPRBRD_USB_REQUEST_GPIOA, VPRBRD_USB_TYPE_OUT,
163 0x0000, 0x0000, gamsg,
164 sizeof(struct vprbrd_gpioa_msg),
165 VPRBRD_USB_TIMEOUT_MS);
166
167 mutex_unlock(&vb->lock);
168
169 if (ret != sizeof(struct vprbrd_gpioa_msg)) {
170 dev_err(chip->parent, "usb error setting pin value\n");
171 return -EREMOTEIO;
172 }
173
174 return 0;
175 }
176
vprbrd_gpioa_direction_input(struct gpio_chip * chip,unsigned int offset)177 static int vprbrd_gpioa_direction_input(struct gpio_chip *chip,
178 unsigned int offset)
179 {
180 int ret;
181 struct vprbrd_gpio *gpio = gpiochip_get_data(chip);
182 struct vprbrd *vb = gpio->vb;
183 struct vprbrd_gpioa_msg *gamsg = (struct vprbrd_gpioa_msg *)vb->buf;
184
185 gpio->gpioa_out &= ~(1 << offset);
186
187 mutex_lock(&vb->lock);
188
189 gamsg->cmd = VPRBRD_GPIOA_CMD_SETIN;
190 gamsg->clk = gpioa_clk;
191 gamsg->offset = offset;
192 gamsg->t1 = 0x00;
193 gamsg->t2 = 0x00;
194 gamsg->invert = 0x00;
195 gamsg->pwmlevel = 0x00;
196 gamsg->outval = 0x00;
197 gamsg->risefall = 0x00;
198 gamsg->answer = 0x00;
199 gamsg->__fill = 0x00;
200
201 ret = usb_control_msg(vb->usb_dev, usb_sndctrlpipe(vb->usb_dev, 0),
202 VPRBRD_USB_REQUEST_GPIOA, VPRBRD_USB_TYPE_OUT, 0x0000,
203 0x0000, gamsg, sizeof(struct vprbrd_gpioa_msg),
204 VPRBRD_USB_TIMEOUT_MS);
205
206 mutex_unlock(&vb->lock);
207
208 if (ret != sizeof(struct vprbrd_gpioa_msg))
209 return -EREMOTEIO;
210
211 return 0;
212 }
213
vprbrd_gpioa_direction_output(struct gpio_chip * chip,unsigned int offset,int value)214 static int vprbrd_gpioa_direction_output(struct gpio_chip *chip,
215 unsigned int offset, int value)
216 {
217 int ret;
218 struct vprbrd_gpio *gpio = gpiochip_get_data(chip);
219 struct vprbrd *vb = gpio->vb;
220 struct vprbrd_gpioa_msg *gamsg = (struct vprbrd_gpioa_msg *)vb->buf;
221
222 gpio->gpioa_out |= (1 << offset);
223 if (value)
224 gpio->gpioa_val |= (1 << offset);
225 else
226 gpio->gpioa_val &= ~(1 << offset);
227
228 mutex_lock(&vb->lock);
229
230 gamsg->cmd = VPRBRD_GPIOA_CMD_SETOUT;
231 gamsg->clk = 0x00;
232 gamsg->offset = offset;
233 gamsg->t1 = 0x00;
234 gamsg->t2 = 0x00;
235 gamsg->invert = 0x00;
236 gamsg->pwmlevel = 0x00;
237 gamsg->outval = value;
238 gamsg->risefall = 0x00;
239 gamsg->answer = 0x00;
240 gamsg->__fill = 0x00;
241
242 ret = usb_control_msg(vb->usb_dev, usb_sndctrlpipe(vb->usb_dev, 0),
243 VPRBRD_USB_REQUEST_GPIOA, VPRBRD_USB_TYPE_OUT, 0x0000,
244 0x0000, gamsg, sizeof(struct vprbrd_gpioa_msg),
245 VPRBRD_USB_TIMEOUT_MS);
246
247 mutex_unlock(&vb->lock);
248
249 if (ret != sizeof(struct vprbrd_gpioa_msg))
250 return -EREMOTEIO;
251
252 return 0;
253 }
254
255 /* ----- end of gpio a chip ---------------------------------------------- */
256
257 /* ----- begin of gipo b chip -------------------------------------------- */
258
vprbrd_gpiob_setdir(struct vprbrd * vb,unsigned int offset,unsigned int dir)259 static int vprbrd_gpiob_setdir(struct vprbrd *vb, unsigned int offset,
260 unsigned int dir)
261 {
262 struct vprbrd_gpiob_msg *gbmsg = (struct vprbrd_gpiob_msg *)vb->buf;
263 int ret;
264
265 gbmsg->cmd = VPRBRD_GPIOB_CMD_SETDIR;
266 gbmsg->val = cpu_to_be16(dir << offset);
267 gbmsg->mask = cpu_to_be16(0x0001 << offset);
268
269 ret = usb_control_msg(vb->usb_dev, usb_sndctrlpipe(vb->usb_dev, 0),
270 VPRBRD_USB_REQUEST_GPIOB, VPRBRD_USB_TYPE_OUT, 0x0000,
271 0x0000, gbmsg, sizeof(struct vprbrd_gpiob_msg),
272 VPRBRD_USB_TIMEOUT_MS);
273
274 if (ret != sizeof(struct vprbrd_gpiob_msg))
275 return -EREMOTEIO;
276
277 return 0;
278 }
279
vprbrd_gpiob_get(struct gpio_chip * chip,unsigned int offset)280 static int vprbrd_gpiob_get(struct gpio_chip *chip,
281 unsigned int offset)
282 {
283 int ret;
284 u16 val;
285 struct vprbrd_gpio *gpio = gpiochip_get_data(chip);
286 struct vprbrd *vb = gpio->vb;
287 struct vprbrd_gpiob_msg *gbmsg = (struct vprbrd_gpiob_msg *)vb->buf;
288
289 /* if io is set to output, just return the saved value */
290 if (gpio->gpiob_out & (1 << offset))
291 return gpio->gpiob_val & (1 << offset);
292
293 mutex_lock(&vb->lock);
294
295 ret = usb_control_msg(vb->usb_dev, usb_rcvctrlpipe(vb->usb_dev, 0),
296 VPRBRD_USB_REQUEST_GPIOB, VPRBRD_USB_TYPE_IN, 0x0000,
297 0x0000, gbmsg, sizeof(struct vprbrd_gpiob_msg),
298 VPRBRD_USB_TIMEOUT_MS);
299 val = gbmsg->val;
300
301 mutex_unlock(&vb->lock);
302
303 if (ret != sizeof(struct vprbrd_gpiob_msg))
304 return ret;
305
306 /* cache the read values */
307 gpio->gpiob_val = be16_to_cpu(val);
308
309 return (gpio->gpiob_val >> offset) & 0x1;
310 }
311
vprbrd_gpiob_set(struct gpio_chip * chip,unsigned int offset,int value)312 static int vprbrd_gpiob_set(struct gpio_chip *chip, unsigned int offset,
313 int value)
314 {
315 int ret;
316 struct vprbrd_gpio *gpio = gpiochip_get_data(chip);
317 struct vprbrd *vb = gpio->vb;
318 struct vprbrd_gpiob_msg *gbmsg = (struct vprbrd_gpiob_msg *)vb->buf;
319
320 if (!(gpio->gpiob_out & (1 << offset)))
321 return 0;
322
323 if (value)
324 gpio->gpiob_val |= (1 << offset);
325 else
326 gpio->gpiob_val &= ~(1 << offset);
327
328 mutex_lock(&vb->lock);
329
330 gbmsg->cmd = VPRBRD_GPIOB_CMD_SETVAL;
331 gbmsg->val = cpu_to_be16(value << offset);
332 gbmsg->mask = cpu_to_be16(0x0001 << offset);
333
334 ret = usb_control_msg(vb->usb_dev, usb_sndctrlpipe(vb->usb_dev, 0),
335 VPRBRD_USB_REQUEST_GPIOB, VPRBRD_USB_TYPE_OUT,
336 0x0000, 0x0000, gbmsg,
337 sizeof(struct vprbrd_gpiob_msg),
338 VPRBRD_USB_TIMEOUT_MS);
339
340 mutex_unlock(&vb->lock);
341
342 if (ret != sizeof(struct vprbrd_gpiob_msg)) {
343 dev_err(chip->parent, "usb error setting pin value\n");
344 return -EREMOTEIO;
345 }
346
347 return 0;
348 }
349
vprbrd_gpiob_direction_input(struct gpio_chip * chip,unsigned int offset)350 static int vprbrd_gpiob_direction_input(struct gpio_chip *chip,
351 unsigned int offset)
352 {
353 int ret;
354 struct vprbrd_gpio *gpio = gpiochip_get_data(chip);
355 struct vprbrd *vb = gpio->vb;
356
357 gpio->gpiob_out &= ~(1 << offset);
358
359 mutex_lock(&vb->lock);
360
361 ret = vprbrd_gpiob_setdir(vb, offset, 0);
362
363 mutex_unlock(&vb->lock);
364
365 if (ret)
366 dev_err(chip->parent, "usb error setting pin to input\n");
367
368 return ret;
369 }
370
vprbrd_gpiob_direction_output(struct gpio_chip * chip,unsigned int offset,int value)371 static int vprbrd_gpiob_direction_output(struct gpio_chip *chip,
372 unsigned int offset, int value)
373 {
374 int ret;
375 struct vprbrd_gpio *gpio = gpiochip_get_data(chip);
376 struct vprbrd *vb = gpio->vb;
377
378 gpio->gpiob_out |= (1 << offset);
379
380 mutex_lock(&vb->lock);
381 ret = vprbrd_gpiob_setdir(vb, offset, 1);
382 mutex_unlock(&vb->lock);
383 if (ret) {
384 dev_err(chip->parent, "usb error setting pin to output\n");
385 return ret;
386 }
387
388 return vprbrd_gpiob_set(chip, offset, value);
389 }
390
391 /* ----- end of gpio b chip ---------------------------------------------- */
392
vprbrd_gpio_probe(struct platform_device * pdev)393 static int vprbrd_gpio_probe(struct platform_device *pdev)
394 {
395 struct vprbrd *vb = dev_get_drvdata(pdev->dev.parent);
396 struct vprbrd_gpio *vb_gpio;
397 int ret;
398
399 vb_gpio = devm_kzalloc(&pdev->dev, sizeof(*vb_gpio), GFP_KERNEL);
400 if (vb_gpio == NULL)
401 return -ENOMEM;
402
403 vb_gpio->vb = vb;
404 /* registering gpio a */
405 vb_gpio->gpioa.label = "viperboard gpio a";
406 vb_gpio->gpioa.parent = &pdev->dev;
407 vb_gpio->gpioa.owner = THIS_MODULE;
408 vb_gpio->gpioa.base = -1;
409 vb_gpio->gpioa.ngpio = 16;
410 vb_gpio->gpioa.can_sleep = true;
411 vb_gpio->gpioa.set_rv = vprbrd_gpioa_set;
412 vb_gpio->gpioa.get = vprbrd_gpioa_get;
413 vb_gpio->gpioa.direction_input = vprbrd_gpioa_direction_input;
414 vb_gpio->gpioa.direction_output = vprbrd_gpioa_direction_output;
415
416 ret = devm_gpiochip_add_data(&pdev->dev, &vb_gpio->gpioa, vb_gpio);
417 if (ret < 0)
418 return ret;
419
420 /* registering gpio b */
421 vb_gpio->gpiob.label = "viperboard gpio b";
422 vb_gpio->gpiob.parent = &pdev->dev;
423 vb_gpio->gpiob.owner = THIS_MODULE;
424 vb_gpio->gpiob.base = -1;
425 vb_gpio->gpiob.ngpio = 16;
426 vb_gpio->gpiob.can_sleep = true;
427 vb_gpio->gpiob.set_rv = vprbrd_gpiob_set;
428 vb_gpio->gpiob.get = vprbrd_gpiob_get;
429 vb_gpio->gpiob.direction_input = vprbrd_gpiob_direction_input;
430 vb_gpio->gpiob.direction_output = vprbrd_gpiob_direction_output;
431
432 return devm_gpiochip_add_data(&pdev->dev, &vb_gpio->gpiob, vb_gpio);
433 }
434
435 static struct platform_driver vprbrd_gpio_driver = {
436 .driver.name = "viperboard-gpio",
437 .probe = vprbrd_gpio_probe,
438 };
439
vprbrd_gpio_init(void)440 static 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 }
468 subsys_initcall(vprbrd_gpio_init);
469
vprbrd_gpio_exit(void)470 static void __exit vprbrd_gpio_exit(void)
471 {
472 platform_driver_unregister(&vprbrd_gpio_driver);
473 }
474 module_exit(vprbrd_gpio_exit);
475
476 MODULE_AUTHOR("Lars Poeschel <poeschel@lemonage.de>");
477 MODULE_DESCRIPTION("GPIO driver for Nano River Techs Viperboard");
478 MODULE_LICENSE("GPL");
479 MODULE_ALIAS("platform:viperboard-gpio");
480