1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3 * Analog Devices Generic AXI ADC IP core
4 * Link: https://wiki.analog.com/resources/fpga/docs/axi_adc_ip
5 *
6 * Copyright 2012-2020 Analog Devices Inc.
7 */
8
9 #include <linux/bitfield.h>
10 #include <linux/clk.h>
11 #include <linux/io.h>
12 #include <linux/delay.h>
13 #include <linux/module.h>
14 #include <linux/of_device.h>
15 #include <linux/platform_device.h>
16 #include <linux/slab.h>
17
18 #include <linux/iio/iio.h>
19 #include <linux/iio/sysfs.h>
20 #include <linux/iio/buffer.h>
21 #include <linux/iio/buffer-dmaengine.h>
22
23 #include <linux/fpga/adi-axi-common.h>
24 #include <linux/iio/adc/adi-axi-adc.h>
25
26 /*
27 * Register definitions:
28 * https://wiki.analog.com/resources/fpga/docs/axi_adc_ip#register_map
29 */
30
31 /* ADC controls */
32
33 #define ADI_AXI_REG_RSTN 0x0040
34 #define ADI_AXI_REG_RSTN_CE_N BIT(2)
35 #define ADI_AXI_REG_RSTN_MMCM_RSTN BIT(1)
36 #define ADI_AXI_REG_RSTN_RSTN BIT(0)
37
38 /* ADC Channel controls */
39
40 #define ADI_AXI_REG_CHAN_CTRL(c) (0x0400 + (c) * 0x40)
41 #define ADI_AXI_REG_CHAN_CTRL_LB_OWR BIT(11)
42 #define ADI_AXI_REG_CHAN_CTRL_PN_SEL_OWR BIT(10)
43 #define ADI_AXI_REG_CHAN_CTRL_IQCOR_EN BIT(9)
44 #define ADI_AXI_REG_CHAN_CTRL_DCFILT_EN BIT(8)
45 #define ADI_AXI_REG_CHAN_CTRL_FMT_SIGNEXT BIT(6)
46 #define ADI_AXI_REG_CHAN_CTRL_FMT_TYPE BIT(5)
47 #define ADI_AXI_REG_CHAN_CTRL_FMT_EN BIT(4)
48 #define ADI_AXI_REG_CHAN_CTRL_PN_TYPE_OWR BIT(1)
49 #define ADI_AXI_REG_CHAN_CTRL_ENABLE BIT(0)
50
51 #define ADI_AXI_REG_CHAN_CTRL_DEFAULTS \
52 (ADI_AXI_REG_CHAN_CTRL_FMT_SIGNEXT | \
53 ADI_AXI_REG_CHAN_CTRL_FMT_EN | \
54 ADI_AXI_REG_CHAN_CTRL_ENABLE)
55
56 struct adi_axi_adc_core_info {
57 unsigned int version;
58 };
59
60 struct adi_axi_adc_state {
61 struct mutex lock;
62
63 struct adi_axi_adc_client *client;
64 void __iomem *regs;
65 };
66
67 struct adi_axi_adc_client {
68 struct list_head entry;
69 struct adi_axi_adc_conv conv;
70 struct adi_axi_adc_state *state;
71 struct device *dev;
72 const struct adi_axi_adc_core_info *info;
73 };
74
75 static LIST_HEAD(registered_clients);
76 static DEFINE_MUTEX(registered_clients_lock);
77
conv_to_client(struct adi_axi_adc_conv * conv)78 static struct adi_axi_adc_client *conv_to_client(struct adi_axi_adc_conv *conv)
79 {
80 return container_of(conv, struct adi_axi_adc_client, conv);
81 }
82
adi_axi_adc_conv_priv(struct adi_axi_adc_conv * conv)83 void *adi_axi_adc_conv_priv(struct adi_axi_adc_conv *conv)
84 {
85 struct adi_axi_adc_client *cl = conv_to_client(conv);
86
87 return (char *)cl + ALIGN(sizeof(struct adi_axi_adc_client), IIO_ALIGN);
88 }
89 EXPORT_SYMBOL_GPL(adi_axi_adc_conv_priv);
90
adi_axi_adc_write(struct adi_axi_adc_state * st,unsigned int reg,unsigned int val)91 static void adi_axi_adc_write(struct adi_axi_adc_state *st,
92 unsigned int reg,
93 unsigned int val)
94 {
95 iowrite32(val, st->regs + reg);
96 }
97
adi_axi_adc_read(struct adi_axi_adc_state * st,unsigned int reg)98 static unsigned int adi_axi_adc_read(struct adi_axi_adc_state *st,
99 unsigned int reg)
100 {
101 return ioread32(st->regs + reg);
102 }
103
adi_axi_adc_config_dma_buffer(struct device * dev,struct iio_dev * indio_dev)104 static int adi_axi_adc_config_dma_buffer(struct device *dev,
105 struct iio_dev *indio_dev)
106 {
107 const char *dma_name;
108
109 if (!device_property_present(dev, "dmas"))
110 return 0;
111
112 if (device_property_read_string(dev, "dma-names", &dma_name))
113 dma_name = "rx";
114
115 return devm_iio_dmaengine_buffer_setup(indio_dev->dev.parent,
116 indio_dev, dma_name);
117 }
118
adi_axi_adc_read_raw(struct iio_dev * indio_dev,struct iio_chan_spec const * chan,int * val,int * val2,long mask)119 static int adi_axi_adc_read_raw(struct iio_dev *indio_dev,
120 struct iio_chan_spec const *chan,
121 int *val, int *val2, long mask)
122 {
123 struct adi_axi_adc_state *st = iio_priv(indio_dev);
124 struct adi_axi_adc_conv *conv = &st->client->conv;
125
126 if (!conv->read_raw)
127 return -EOPNOTSUPP;
128
129 return conv->read_raw(conv, chan, val, val2, mask);
130 }
131
adi_axi_adc_write_raw(struct iio_dev * indio_dev,struct iio_chan_spec const * chan,int val,int val2,long mask)132 static int adi_axi_adc_write_raw(struct iio_dev *indio_dev,
133 struct iio_chan_spec const *chan,
134 int val, int val2, long mask)
135 {
136 struct adi_axi_adc_state *st = iio_priv(indio_dev);
137 struct adi_axi_adc_conv *conv = &st->client->conv;
138
139 if (!conv->write_raw)
140 return -EOPNOTSUPP;
141
142 return conv->write_raw(conv, chan, val, val2, mask);
143 }
144
adi_axi_adc_update_scan_mode(struct iio_dev * indio_dev,const unsigned long * scan_mask)145 static int adi_axi_adc_update_scan_mode(struct iio_dev *indio_dev,
146 const unsigned long *scan_mask)
147 {
148 struct adi_axi_adc_state *st = iio_priv(indio_dev);
149 struct adi_axi_adc_conv *conv = &st->client->conv;
150 unsigned int i, ctrl;
151
152 for (i = 0; i < conv->chip_info->num_channels; i++) {
153 ctrl = adi_axi_adc_read(st, ADI_AXI_REG_CHAN_CTRL(i));
154
155 if (test_bit(i, scan_mask))
156 ctrl |= ADI_AXI_REG_CHAN_CTRL_ENABLE;
157 else
158 ctrl &= ~ADI_AXI_REG_CHAN_CTRL_ENABLE;
159
160 adi_axi_adc_write(st, ADI_AXI_REG_CHAN_CTRL(i), ctrl);
161 }
162
163 return 0;
164 }
165
adi_axi_adc_conv_register(struct device * dev,size_t sizeof_priv)166 static struct adi_axi_adc_conv *adi_axi_adc_conv_register(struct device *dev,
167 size_t sizeof_priv)
168 {
169 struct adi_axi_adc_client *cl;
170 size_t alloc_size;
171
172 alloc_size = ALIGN(sizeof(struct adi_axi_adc_client), IIO_ALIGN);
173 if (sizeof_priv)
174 alloc_size += ALIGN(sizeof_priv, IIO_ALIGN);
175
176 cl = kzalloc(alloc_size, GFP_KERNEL);
177 if (!cl)
178 return ERR_PTR(-ENOMEM);
179
180 mutex_lock(®istered_clients_lock);
181
182 cl->dev = get_device(dev);
183
184 list_add_tail(&cl->entry, ®istered_clients);
185
186 mutex_unlock(®istered_clients_lock);
187
188 return &cl->conv;
189 }
190
adi_axi_adc_conv_unregister(struct adi_axi_adc_conv * conv)191 static void adi_axi_adc_conv_unregister(struct adi_axi_adc_conv *conv)
192 {
193 struct adi_axi_adc_client *cl = conv_to_client(conv);
194
195 mutex_lock(®istered_clients_lock);
196
197 list_del(&cl->entry);
198 put_device(cl->dev);
199
200 mutex_unlock(®istered_clients_lock);
201
202 kfree(cl);
203 }
204
devm_adi_axi_adc_conv_release(void * conv)205 static void devm_adi_axi_adc_conv_release(void *conv)
206 {
207 adi_axi_adc_conv_unregister(conv);
208 }
209
devm_adi_axi_adc_conv_register(struct device * dev,size_t sizeof_priv)210 struct adi_axi_adc_conv *devm_adi_axi_adc_conv_register(struct device *dev,
211 size_t sizeof_priv)
212 {
213 struct adi_axi_adc_conv *conv;
214 int ret;
215
216 conv = adi_axi_adc_conv_register(dev, sizeof_priv);
217 if (IS_ERR(conv))
218 return conv;
219
220 ret = devm_add_action_or_reset(dev, devm_adi_axi_adc_conv_release,
221 conv);
222 if (ret)
223 return ERR_PTR(ret);
224
225 return conv;
226 }
227 EXPORT_SYMBOL_GPL(devm_adi_axi_adc_conv_register);
228
in_voltage_scale_available_show(struct device * dev,struct device_attribute * attr,char * buf)229 static ssize_t in_voltage_scale_available_show(struct device *dev,
230 struct device_attribute *attr,
231 char *buf)
232 {
233 struct iio_dev *indio_dev = dev_to_iio_dev(dev);
234 struct adi_axi_adc_state *st = iio_priv(indio_dev);
235 struct adi_axi_adc_conv *conv = &st->client->conv;
236 size_t len = 0;
237 int i;
238
239 for (i = 0; i < conv->chip_info->num_scales; i++) {
240 const unsigned int *s = conv->chip_info->scale_table[i];
241
242 len += scnprintf(buf + len, PAGE_SIZE - len,
243 "%u.%06u ", s[0], s[1]);
244 }
245 buf[len - 1] = '\n';
246
247 return len;
248 }
249
250 static IIO_DEVICE_ATTR_RO(in_voltage_scale_available, 0);
251
252 enum {
253 ADI_AXI_ATTR_SCALE_AVAIL,
254 };
255
256 #define ADI_AXI_ATTR(_en_, _file_) \
257 [ADI_AXI_ATTR_##_en_] = &iio_dev_attr_##_file_.dev_attr.attr
258
259 static struct attribute *adi_axi_adc_attributes[] = {
260 ADI_AXI_ATTR(SCALE_AVAIL, in_voltage_scale_available),
261 NULL
262 };
263
axi_adc_attr_is_visible(struct kobject * kobj,struct attribute * attr,int n)264 static umode_t axi_adc_attr_is_visible(struct kobject *kobj,
265 struct attribute *attr, int n)
266 {
267 struct device *dev = kobj_to_dev(kobj);
268 struct iio_dev *indio_dev = dev_to_iio_dev(dev);
269 struct adi_axi_adc_state *st = iio_priv(indio_dev);
270 struct adi_axi_adc_conv *conv = &st->client->conv;
271
272 switch (n) {
273 case ADI_AXI_ATTR_SCALE_AVAIL:
274 if (!conv->chip_info->num_scales)
275 return 0;
276 return attr->mode;
277 default:
278 return attr->mode;
279 }
280 }
281
282 static const struct attribute_group adi_axi_adc_attribute_group = {
283 .attrs = adi_axi_adc_attributes,
284 .is_visible = axi_adc_attr_is_visible,
285 };
286
287 static const struct iio_info adi_axi_adc_info = {
288 .read_raw = &adi_axi_adc_read_raw,
289 .write_raw = &adi_axi_adc_write_raw,
290 .attrs = &adi_axi_adc_attribute_group,
291 .update_scan_mode = &adi_axi_adc_update_scan_mode,
292 };
293
294 static const struct adi_axi_adc_core_info adi_axi_adc_10_0_a_info = {
295 .version = ADI_AXI_PCORE_VER(10, 0, 'a'),
296 };
297
adi_axi_adc_attach_client(struct device * dev)298 static struct adi_axi_adc_client *adi_axi_adc_attach_client(struct device *dev)
299 {
300 const struct adi_axi_adc_core_info *info;
301 struct adi_axi_adc_client *cl;
302 struct device_node *cln;
303
304 info = of_device_get_match_data(dev);
305 if (!info)
306 return ERR_PTR(-ENODEV);
307
308 cln = of_parse_phandle(dev->of_node, "adi,adc-dev", 0);
309 if (!cln) {
310 dev_err(dev, "No 'adi,adc-dev' node defined\n");
311 return ERR_PTR(-ENODEV);
312 }
313
314 mutex_lock(®istered_clients_lock);
315
316 list_for_each_entry(cl, ®istered_clients, entry) {
317 if (!cl->dev)
318 continue;
319
320 if (cl->dev->of_node != cln)
321 continue;
322
323 if (!try_module_get(cl->dev->driver->owner)) {
324 mutex_unlock(®istered_clients_lock);
325 return ERR_PTR(-ENODEV);
326 }
327
328 get_device(cl->dev);
329 cl->info = info;
330 mutex_unlock(®istered_clients_lock);
331 return cl;
332 }
333
334 mutex_unlock(®istered_clients_lock);
335
336 return ERR_PTR(-EPROBE_DEFER);
337 }
338
adi_axi_adc_setup_channels(struct device * dev,struct adi_axi_adc_state * st)339 static int adi_axi_adc_setup_channels(struct device *dev,
340 struct adi_axi_adc_state *st)
341 {
342 struct adi_axi_adc_conv *conv = &st->client->conv;
343 int i, ret;
344
345 if (conv->preenable_setup) {
346 ret = conv->preenable_setup(conv);
347 if (ret)
348 return ret;
349 }
350
351 for (i = 0; i < conv->chip_info->num_channels; i++) {
352 adi_axi_adc_write(st, ADI_AXI_REG_CHAN_CTRL(i),
353 ADI_AXI_REG_CHAN_CTRL_DEFAULTS);
354 }
355
356 return 0;
357 }
358
axi_adc_reset(struct adi_axi_adc_state * st)359 static void axi_adc_reset(struct adi_axi_adc_state *st)
360 {
361 adi_axi_adc_write(st, ADI_AXI_REG_RSTN, 0);
362 mdelay(10);
363 adi_axi_adc_write(st, ADI_AXI_REG_RSTN, ADI_AXI_REG_RSTN_MMCM_RSTN);
364 mdelay(10);
365 adi_axi_adc_write(st, ADI_AXI_REG_RSTN,
366 ADI_AXI_REG_RSTN_RSTN | ADI_AXI_REG_RSTN_MMCM_RSTN);
367 }
368
adi_axi_adc_cleanup(void * data)369 static void adi_axi_adc_cleanup(void *data)
370 {
371 struct adi_axi_adc_client *cl = data;
372
373 put_device(cl->dev);
374 module_put(cl->dev->driver->owner);
375 }
376
adi_axi_adc_probe(struct platform_device * pdev)377 static int adi_axi_adc_probe(struct platform_device *pdev)
378 {
379 struct adi_axi_adc_conv *conv;
380 struct iio_dev *indio_dev;
381 struct adi_axi_adc_client *cl;
382 struct adi_axi_adc_state *st;
383 unsigned int ver;
384 int ret;
385
386 cl = adi_axi_adc_attach_client(&pdev->dev);
387 if (IS_ERR(cl))
388 return PTR_ERR(cl);
389
390 ret = devm_add_action_or_reset(&pdev->dev, adi_axi_adc_cleanup, cl);
391 if (ret)
392 return ret;
393
394 indio_dev = devm_iio_device_alloc(&pdev->dev, sizeof(*st));
395 if (indio_dev == NULL)
396 return -ENOMEM;
397
398 st = iio_priv(indio_dev);
399 st->client = cl;
400 cl->state = st;
401 mutex_init(&st->lock);
402
403 st->regs = devm_platform_ioremap_resource(pdev, 0);
404 if (IS_ERR(st->regs))
405 return PTR_ERR(st->regs);
406
407 conv = &st->client->conv;
408
409 axi_adc_reset(st);
410
411 ver = adi_axi_adc_read(st, ADI_AXI_REG_VERSION);
412
413 if (cl->info->version > ver) {
414 dev_err(&pdev->dev,
415 "IP core version is too old. Expected %d.%.2d.%c, Reported %d.%.2d.%c\n",
416 ADI_AXI_PCORE_VER_MAJOR(cl->info->version),
417 ADI_AXI_PCORE_VER_MINOR(cl->info->version),
418 ADI_AXI_PCORE_VER_PATCH(cl->info->version),
419 ADI_AXI_PCORE_VER_MAJOR(ver),
420 ADI_AXI_PCORE_VER_MINOR(ver),
421 ADI_AXI_PCORE_VER_PATCH(ver));
422 return -ENODEV;
423 }
424
425 indio_dev->info = &adi_axi_adc_info;
426 indio_dev->name = "adi-axi-adc";
427 indio_dev->modes = INDIO_DIRECT_MODE;
428 indio_dev->num_channels = conv->chip_info->num_channels;
429 indio_dev->channels = conv->chip_info->channels;
430
431 ret = adi_axi_adc_config_dma_buffer(&pdev->dev, indio_dev);
432 if (ret)
433 return ret;
434
435 ret = adi_axi_adc_setup_channels(&pdev->dev, st);
436 if (ret)
437 return ret;
438
439 ret = devm_iio_device_register(&pdev->dev, indio_dev);
440 if (ret)
441 return ret;
442
443 dev_info(&pdev->dev, "AXI ADC IP core (%d.%.2d.%c) probed\n",
444 ADI_AXI_PCORE_VER_MAJOR(ver),
445 ADI_AXI_PCORE_VER_MINOR(ver),
446 ADI_AXI_PCORE_VER_PATCH(ver));
447
448 return 0;
449 }
450
451 /* Match table for of_platform binding */
452 static const struct of_device_id adi_axi_adc_of_match[] = {
453 { .compatible = "adi,axi-adc-10.0.a", .data = &adi_axi_adc_10_0_a_info },
454 { /* end of list */ }
455 };
456 MODULE_DEVICE_TABLE(of, adi_axi_adc_of_match);
457
458 static struct platform_driver adi_axi_adc_driver = {
459 .driver = {
460 .name = KBUILD_MODNAME,
461 .of_match_table = adi_axi_adc_of_match,
462 },
463 .probe = adi_axi_adc_probe,
464 };
465 module_platform_driver(adi_axi_adc_driver);
466
467 MODULE_AUTHOR("Michael Hennerich <michael.hennerich@analog.com>");
468 MODULE_DESCRIPTION("Analog Devices Generic AXI ADC IP core driver");
469 MODULE_LICENSE("GPL v2");
470