2 * ad2s1210.c support for the ADI Resolver to Digital Converters: AD2S1210
4 * Copyright (c) 2010-2010 Analog Devices Inc.
6 * This program is free software; you can redistribute it and/or modify
7 * it under the terms of the GNU General Public License version 2 as
8 * published by the Free Software Foundation.
11 #include <linux/types.h>
12 #include <linux/mutex.h>
13 #include <linux/device.h>
14 #include <linux/spi/spi.h>
15 #include <linux/slab.h>
16 #include <linux/sysfs.h>
17 #include <linux/delay.h>
18 #include <linux/gpio.h>
19 #include <linux/module.h>
25 #define DRV_NAME "ad2s1210"
27 #define AD2S1210_DEF_CONTROL 0x7E
29 #define AD2S1210_MSB_IS_HIGH 0x80
30 #define AD2S1210_MSB_IS_LOW 0x7F
31 #define AD2S1210_PHASE_LOCK_RANGE_44 0x20
32 #define AD2S1210_ENABLE_HYSTERESIS 0x10
33 #define AD2S1210_SET_ENRES1 0x08
34 #define AD2S1210_SET_ENRES0 0x04
35 #define AD2S1210_SET_RES1 0x02
36 #define AD2S1210_SET_RES0 0x01
38 #define AD2S1210_SET_ENRESOLUTION (AD2S1210_SET_ENRES1 | \
40 #define AD2S1210_SET_RESOLUTION (AD2S1210_SET_RES1 | AD2S1210_SET_RES0)
42 #define AD2S1210_REG_POSITION 0x80
43 #define AD2S1210_REG_VELOCITY 0x82
44 #define AD2S1210_REG_LOS_THRD 0x88
45 #define AD2S1210_REG_DOS_OVR_THRD 0x89
46 #define AD2S1210_REG_DOS_MIS_THRD 0x8A
47 #define AD2S1210_REG_DOS_RST_MAX_THRD 0x8B
48 #define AD2S1210_REG_DOS_RST_MIN_THRD 0x8C
49 #define AD2S1210_REG_LOT_HIGH_THRD 0x8D
50 #define AD2S1210_REG_LOT_LOW_THRD 0x8E
51 #define AD2S1210_REG_EXCIT_FREQ 0x91
52 #define AD2S1210_REG_CONTROL 0x92
53 #define AD2S1210_REG_SOFT_RESET 0xF0
54 #define AD2S1210_REG_FAULT 0xFF
56 /* pin SAMPLE, A0, A1, RES0, RES1, is controlled by driver */
57 #define AD2S1210_SAA 3
58 #define AD2S1210_PN (AD2S1210_SAA + AD2S1210_RES)
60 #define AD2S1210_MIN_CLKIN 6144000
61 #define AD2S1210_MAX_CLKIN 10240000
62 #define AD2S1210_MIN_EXCIT 2000
63 #define AD2S1210_MAX_EXCIT 20000
64 #define AD2S1210_MIN_FCW 0x4
65 #define AD2S1210_MAX_FCW 0x50
67 /* default input clock on serial interface */
68 #define AD2S1210_DEF_CLKIN 8192000
69 /* clock period in nano second */
70 #define AD2S1210_DEF_TCK (1000000000/AD2S1210_DEF_CLKIN)
71 #define AD2S1210_DEF_EXCIT 10000
80 static const unsigned int ad2s1210_resolution_value[] = { 10, 12, 14, 16 };
82 struct ad2s1210_state {
83 const struct ad2s1210_platform_data *pdata;
85 struct spi_device *sdev;
91 enum ad2s1210_mode mode;
92 u8 rx[2] ____cacheline_aligned;
93 u8 tx[2] ____cacheline_aligned;
96 static const int ad2s1210_mode_vals[4][2] = {
99 [MOD_CONFIG] = { 1, 0 },
101 static inline void ad2s1210_set_mode(enum ad2s1210_mode mode,
102 struct ad2s1210_state *st)
104 gpio_set_value(st->pdata->a[0], ad2s1210_mode_vals[mode][0]);
105 gpio_set_value(st->pdata->a[1], ad2s1210_mode_vals[mode][1]);
109 /* write 1 bytes (address or data) to the chip */
110 static int ad2s1210_config_write(struct ad2s1210_state *st, u8 data)
114 ad2s1210_set_mode(MOD_CONFIG, st);
116 ret = spi_write(st->sdev, st->tx, 1);
124 /* read value from one of the registers */
125 static int ad2s1210_config_read(struct ad2s1210_state *st,
126 unsigned char address)
128 struct spi_transfer xfer = {
133 struct spi_message msg;
136 ad2s1210_set_mode(MOD_CONFIG, st);
137 spi_message_init(&msg);
138 spi_message_add_tail(&xfer, &msg);
139 st->tx[0] = address | AD2S1210_MSB_IS_HIGH;
140 st->tx[1] = AD2S1210_REG_FAULT;
141 ret = spi_sync(st->sdev, &msg);
150 int ad2s1210_update_frequency_control_word(struct ad2s1210_state *st)
155 fcw = (unsigned char)(st->fexcit * (1 << 15) / st->fclkin);
156 if (fcw < AD2S1210_MIN_FCW || fcw > AD2S1210_MAX_FCW) {
157 pr_err("ad2s1210: FCW out of range\n");
161 ret = ad2s1210_config_write(st, AD2S1210_REG_EXCIT_FREQ);
165 return ad2s1210_config_write(st, fcw);
168 static unsigned char ad2s1210_read_resolution_pin(struct ad2s1210_state *st)
170 return ad2s1210_resolution_value[
171 (gpio_get_value(st->pdata->res[0]) << 1) |
172 gpio_get_value(st->pdata->res[1])];
175 static const int ad2s1210_res_pins[4][2] = {
176 { 0, 0 }, {0, 1}, {1, 0}, {1, 1}
179 static inline void ad2s1210_set_resolution_pin(struct ad2s1210_state *st)
181 gpio_set_value(st->pdata->res[0],
182 ad2s1210_res_pins[(st->resolution - 10)/2][0]);
183 gpio_set_value(st->pdata->res[1],
184 ad2s1210_res_pins[(st->resolution - 10)/2][1]);
187 static inline int ad2s1210_soft_reset(struct ad2s1210_state *st)
191 ret = ad2s1210_config_write(st, AD2S1210_REG_SOFT_RESET);
195 return ad2s1210_config_write(st, 0x0);
199 /* return the OLD DATA since last spi bus write */
200 static ssize_t ad2s1210_show_raw(struct device *dev,
201 struct device_attribute *attr,
204 struct ad2s1210_state *st = iio_priv(dev_get_drvdata(dev));
207 mutex_lock(&st->lock);
209 ret = sprintf(buf, "0x%x\n", st->rx[0]);
210 st->old_data = false;
212 mutex_unlock(&st->lock);
217 static ssize_t ad2s1210_store_raw(struct device *dev,
218 struct device_attribute *attr,
222 struct ad2s1210_state *st = iio_priv(dev_get_drvdata(dev));
227 ret = strict_strtoul(buf, 16, &udata);
232 mutex_lock(&st->lock);
233 ret = ad2s1210_config_write(st, data);
234 mutex_unlock(&st->lock);
236 return ret < 0 ? ret : len;
239 static ssize_t ad2s1210_store_softreset(struct device *dev,
240 struct device_attribute *attr,
244 struct ad2s1210_state *st = iio_priv(dev_get_drvdata(dev));
247 mutex_lock(&st->lock);
248 ret = ad2s1210_soft_reset(st);
249 mutex_unlock(&st->lock);
251 return ret < 0 ? ret : len;
254 static ssize_t ad2s1210_show_fclkin(struct device *dev,
255 struct device_attribute *attr,
258 struct ad2s1210_state *st = iio_priv(dev_get_drvdata(dev));
259 return sprintf(buf, "%d\n", st->fclkin);
262 static ssize_t ad2s1210_store_fclkin(struct device *dev,
263 struct device_attribute *attr,
267 struct ad2s1210_state *st = iio_priv(dev_get_drvdata(dev));
268 unsigned long fclkin;
271 ret = strict_strtoul(buf, 10, &fclkin);
274 if (fclkin < AD2S1210_MIN_CLKIN || fclkin > AD2S1210_MAX_CLKIN) {
275 pr_err("ad2s1210: fclkin out of range\n");
279 mutex_lock(&st->lock);
282 ret = ad2s1210_update_frequency_control_word(st);
285 ret = ad2s1210_soft_reset(st);
287 mutex_unlock(&st->lock);
289 return ret < 0 ? ret : len;
292 static ssize_t ad2s1210_show_fexcit(struct device *dev,
293 struct device_attribute *attr,
296 struct ad2s1210_state *st = iio_priv(dev_get_drvdata(dev));
297 return sprintf(buf, "%d\n", st->fexcit);
300 static ssize_t ad2s1210_store_fexcit(struct device *dev,
301 struct device_attribute *attr,
302 const char *buf, size_t len)
304 struct ad2s1210_state *st = iio_priv(dev_get_drvdata(dev));
305 unsigned long fexcit;
308 ret = strict_strtoul(buf, 10, &fexcit);
311 if (fexcit < AD2S1210_MIN_EXCIT || fexcit > AD2S1210_MAX_EXCIT) {
312 pr_err("ad2s1210: excitation frequency out of range\n");
315 mutex_lock(&st->lock);
317 ret = ad2s1210_update_frequency_control_word(st);
320 ret = ad2s1210_soft_reset(st);
322 mutex_unlock(&st->lock);
324 return ret < 0 ? ret : len;
327 static ssize_t ad2s1210_show_control(struct device *dev,
328 struct device_attribute *attr,
331 struct ad2s1210_state *st = iio_priv(dev_get_drvdata(dev));
333 mutex_lock(&st->lock);
334 ret = ad2s1210_config_read(st, AD2S1210_REG_CONTROL);
335 mutex_unlock(&st->lock);
336 return ret < 0 ? ret : sprintf(buf, "0x%x\n", ret);
339 static ssize_t ad2s1210_store_control(struct device *dev,
340 struct device_attribute *attr,
341 const char *buf, size_t len)
343 struct ad2s1210_state *st = iio_priv(dev_get_drvdata(dev));
348 ret = strict_strtoul(buf, 16, &udata);
352 mutex_lock(&st->lock);
353 ret = ad2s1210_config_write(st, AD2S1210_REG_CONTROL);
356 data = udata & AD2S1210_MSB_IS_LOW;
357 ret = ad2s1210_config_write(st, data);
361 ret = ad2s1210_config_read(st, AD2S1210_REG_CONTROL);
364 if (ret & AD2S1210_MSB_IS_HIGH) {
366 pr_err("ad2s1210: write control register fail\n");
370 = ad2s1210_resolution_value[data & AD2S1210_SET_RESOLUTION];
371 if (st->pdata->gpioin) {
372 data = ad2s1210_read_resolution_pin(st);
373 if (data != st->resolution)
374 pr_warning("ad2s1210: resolution settings not match\n");
376 ad2s1210_set_resolution_pin(st);
379 st->hysteresis = !!(data & AD2S1210_ENABLE_HYSTERESIS);
382 mutex_unlock(&st->lock);
386 static ssize_t ad2s1210_show_resolution(struct device *dev,
387 struct device_attribute *attr, char *buf)
389 struct ad2s1210_state *st = iio_priv(dev_get_drvdata(dev));
390 return sprintf(buf, "%d\n", st->resolution);
393 static ssize_t ad2s1210_store_resolution(struct device *dev,
394 struct device_attribute *attr,
395 const char *buf, size_t len)
397 struct ad2s1210_state *st = iio_priv(dev_get_drvdata(dev));
402 ret = strict_strtoul(buf, 10, &udata);
403 if (ret || udata < 10 || udata > 16) {
404 pr_err("ad2s1210: resolution out of range\n");
407 mutex_lock(&st->lock);
408 ret = ad2s1210_config_read(st, AD2S1210_REG_CONTROL);
412 data &= ~AD2S1210_SET_RESOLUTION;
413 data |= (udata - 10) >> 1;
414 ret = ad2s1210_config_write(st, AD2S1210_REG_CONTROL);
417 ret = ad2s1210_config_write(st, data & AD2S1210_MSB_IS_LOW);
420 ret = ad2s1210_config_read(st, AD2S1210_REG_CONTROL);
424 if (data & AD2S1210_MSB_IS_HIGH) {
426 pr_err("ad2s1210: setting resolution fail\n");
430 = ad2s1210_resolution_value[data & AD2S1210_SET_RESOLUTION];
431 if (st->pdata->gpioin) {
432 data = ad2s1210_read_resolution_pin(st);
433 if (data != st->resolution)
434 pr_warning("ad2s1210: resolution settings not match\n");
436 ad2s1210_set_resolution_pin(st);
439 mutex_unlock(&st->lock);
443 /* read the fault register since last sample */
444 static ssize_t ad2s1210_show_fault(struct device *dev,
445 struct device_attribute *attr, char *buf)
447 struct ad2s1210_state *st = iio_priv(dev_get_drvdata(dev));
450 mutex_lock(&st->lock);
451 ret = ad2s1210_config_read(st, AD2S1210_REG_FAULT);
452 mutex_unlock(&st->lock);
454 return ret ? ret : sprintf(buf, "0x%x\n", ret);
457 static ssize_t ad2s1210_clear_fault(struct device *dev,
458 struct device_attribute *attr,
462 struct ad2s1210_state *st = iio_priv(dev_get_drvdata(dev));
465 mutex_lock(&st->lock);
466 gpio_set_value(st->pdata->sample, 0);
467 /* delay (2 * tck + 20) nano seconds */
469 gpio_set_value(st->pdata->sample, 1);
470 ret = ad2s1210_config_read(st, AD2S1210_REG_FAULT);
473 gpio_set_value(st->pdata->sample, 0);
474 gpio_set_value(st->pdata->sample, 1);
476 mutex_unlock(&st->lock);
478 return ret < 0 ? ret : len;
481 static ssize_t ad2s1210_show_reg(struct device *dev,
482 struct device_attribute *attr,
485 struct ad2s1210_state *st = iio_priv(dev_get_drvdata(dev));
486 struct iio_dev_attr *iattr = to_iio_dev_attr(attr);
489 mutex_lock(&st->lock);
490 ret = ad2s1210_config_read(st, iattr->address);
491 mutex_unlock(&st->lock);
493 return ret < 0 ? ret : sprintf(buf, "%d\n", ret);
496 static ssize_t ad2s1210_store_reg(struct device *dev,
497 struct device_attribute *attr, const char *buf, size_t len)
499 struct ad2s1210_state *st = iio_priv(dev_get_drvdata(dev));
502 struct iio_dev_attr *iattr = to_iio_dev_attr(attr);
504 ret = strict_strtoul(buf, 10, &data);
507 mutex_lock(&st->lock);
508 ret = ad2s1210_config_write(st, iattr->address);
511 ret = ad2s1210_config_write(st, data & AD2S1210_MSB_IS_LOW);
513 mutex_unlock(&st->lock);
514 return ret < 0 ? ret : len;
517 static ssize_t ad2s1210_show_pos(struct device *dev,
518 struct device_attribute *attr,
524 struct ad2s1210_state *st = iio_priv(dev_get_drvdata(dev));
526 mutex_lock(&st->lock);
527 gpio_set_value(st->pdata->sample, 0);
528 /* delay (6 * tck + 20) nano seconds */
531 ad2s1210_set_mode(MOD_POS, st);
532 ret = spi_read(st->sdev, st->rx, 2);
535 pos = be16_to_cpup((u16 *)st->rx);
537 pos >>= 16 - st->resolution;
538 len = sprintf(buf, "%d\n", pos);
540 gpio_set_value(st->pdata->sample, 1);
541 /* delay (2 * tck + 20) nano seconds */
543 mutex_unlock(&st->lock);
545 return ret < 0 ? ret : len;
548 static ssize_t ad2s1210_show_vel(struct device *dev,
549 struct device_attribute *attr,
552 unsigned short negative;
556 struct ad2s1210_state *st = iio_priv(dev_get_drvdata(dev));
558 mutex_lock(&st->lock);
559 gpio_set_value(st->pdata->sample, 0);
560 /* delay (6 * tck + 20) nano seconds */
563 ad2s1210_set_mode(MOD_VEL, st);
564 ret = spi_read(st->sdev, st->rx, 2);
567 negative = st->rx[0] & 0x80;
568 vel = be16_to_cpup((s16 *)st->rx);
569 vel >>= 16 - st->resolution;
571 negative = (0xffff >> st->resolution) << st->resolution;
574 len = sprintf(buf, "%d\n", vel);
576 gpio_set_value(st->pdata->sample, 1);
577 /* delay (2 * tck + 20) nano seconds */
579 mutex_unlock(&st->lock);
581 return ret < 0 ? ret : len;
584 static IIO_DEVICE_ATTR(raw_io, S_IRUGO | S_IWUSR,
585 ad2s1210_show_raw, ad2s1210_store_raw, 0);
586 static IIO_DEVICE_ATTR(reset, S_IWUSR,
587 NULL, ad2s1210_store_softreset, 0);
588 static IIO_DEVICE_ATTR(fclkin, S_IRUGO | S_IWUSR,
589 ad2s1210_show_fclkin, ad2s1210_store_fclkin, 0);
590 static IIO_DEVICE_ATTR(fexcit, S_IRUGO | S_IWUSR,
591 ad2s1210_show_fexcit, ad2s1210_store_fexcit, 0);
592 static IIO_DEVICE_ATTR(control, S_IRUGO | S_IWUSR,
593 ad2s1210_show_control, ad2s1210_store_control, 0);
594 static IIO_DEVICE_ATTR(bits, S_IRUGO | S_IWUSR,
595 ad2s1210_show_resolution, ad2s1210_store_resolution, 0);
596 static IIO_DEVICE_ATTR(fault, S_IRUGO | S_IWUSR,
597 ad2s1210_show_fault, ad2s1210_clear_fault, 0);
598 static IIO_DEVICE_ATTR(pos, S_IRUGO, ad2s1210_show_pos, NULL, 0);
599 static IIO_DEVICE_ATTR(vel, S_IRUGO, ad2s1210_show_vel, NULL, 0);
600 static IIO_DEVICE_ATTR(los_thrd, S_IRUGO | S_IWUSR,
601 ad2s1210_show_reg, ad2s1210_store_reg,
602 AD2S1210_REG_LOS_THRD);
603 static IIO_DEVICE_ATTR(dos_ovr_thrd, S_IRUGO | S_IWUSR,
604 ad2s1210_show_reg, ad2s1210_store_reg,
605 AD2S1210_REG_DOS_OVR_THRD);
606 static IIO_DEVICE_ATTR(dos_mis_thrd, S_IRUGO | S_IWUSR,
607 ad2s1210_show_reg, ad2s1210_store_reg,
608 AD2S1210_REG_DOS_MIS_THRD);
609 static IIO_DEVICE_ATTR(dos_rst_max_thrd, S_IRUGO | S_IWUSR,
610 ad2s1210_show_reg, ad2s1210_store_reg,
611 AD2S1210_REG_DOS_RST_MAX_THRD);
612 static IIO_DEVICE_ATTR(dos_rst_min_thrd, S_IRUGO | S_IWUSR,
613 ad2s1210_show_reg, ad2s1210_store_reg,
614 AD2S1210_REG_DOS_RST_MIN_THRD);
615 static IIO_DEVICE_ATTR(lot_high_thrd, S_IRUGO | S_IWUSR,
616 ad2s1210_show_reg, ad2s1210_store_reg,
617 AD2S1210_REG_LOT_HIGH_THRD);
618 static IIO_DEVICE_ATTR(lot_low_thrd, S_IRUGO | S_IWUSR,
619 ad2s1210_show_reg, ad2s1210_store_reg,
620 AD2S1210_REG_LOT_LOW_THRD);
622 static struct attribute *ad2s1210_attributes[] = {
623 &iio_dev_attr_raw_io.dev_attr.attr,
624 &iio_dev_attr_reset.dev_attr.attr,
625 &iio_dev_attr_fclkin.dev_attr.attr,
626 &iio_dev_attr_fexcit.dev_attr.attr,
627 &iio_dev_attr_control.dev_attr.attr,
628 &iio_dev_attr_bits.dev_attr.attr,
629 &iio_dev_attr_fault.dev_attr.attr,
630 &iio_dev_attr_pos.dev_attr.attr,
631 &iio_dev_attr_vel.dev_attr.attr,
632 &iio_dev_attr_los_thrd.dev_attr.attr,
633 &iio_dev_attr_dos_ovr_thrd.dev_attr.attr,
634 &iio_dev_attr_dos_mis_thrd.dev_attr.attr,
635 &iio_dev_attr_dos_rst_max_thrd.dev_attr.attr,
636 &iio_dev_attr_dos_rst_min_thrd.dev_attr.attr,
637 &iio_dev_attr_lot_high_thrd.dev_attr.attr,
638 &iio_dev_attr_lot_low_thrd.dev_attr.attr,
642 static const struct attribute_group ad2s1210_attribute_group = {
643 .attrs = ad2s1210_attributes,
646 static int __devinit ad2s1210_initial(struct ad2s1210_state *st)
651 mutex_lock(&st->lock);
652 if (st->pdata->gpioin)
653 st->resolution = ad2s1210_read_resolution_pin(st);
655 ad2s1210_set_resolution_pin(st);
657 ret = ad2s1210_config_write(st, AD2S1210_REG_CONTROL);
660 data = AD2S1210_DEF_CONTROL & ~(AD2S1210_SET_RESOLUTION);
661 data |= (st->resolution - 10) >> 1;
662 ret = ad2s1210_config_write(st, data);
665 ret = ad2s1210_config_read(st, AD2S1210_REG_CONTROL);
669 if (ret & AD2S1210_MSB_IS_HIGH) {
674 ret = ad2s1210_update_frequency_control_word(st);
677 ret = ad2s1210_soft_reset(st);
679 mutex_unlock(&st->lock);
683 static const struct iio_info ad2s1210_info = {
684 .attrs = &ad2s1210_attribute_group,
685 .driver_module = THIS_MODULE,
688 static int ad2s1210_setup_gpios(struct ad2s1210_state *st)
691 unsigned long flags = st->pdata->gpioin ? GPIOF_DIR_IN : GPIOF_DIR_OUT;
693 ret = gpio_request_one(st->pdata->sample, GPIOF_DIR_IN, "sample");
696 ret = gpio_request_one(st->pdata->a[0], flags, "a0");
698 goto error_free_sample;
699 ret = gpio_request_one(st->pdata->a[1], flags, "a1");
702 ret = gpio_request_one(st->pdata->res[1], flags, "res0");
705 ret = gpio_request_one(st->pdata->res[1], flags, "res1");
707 goto error_free_res0;
711 gpio_free(st->pdata->res[0]);
713 gpio_free(st->pdata->a[1]);
715 gpio_free(st->pdata->a[0]);
717 gpio_free(st->pdata->sample);
722 static void ad2s1210_free_gpios(struct ad2s1210_state *st)
724 gpio_free(st->pdata->res[1]);
725 gpio_free(st->pdata->res[0]);
726 gpio_free(st->pdata->a[1]);
727 gpio_free(st->pdata->a[0]);
728 gpio_free(st->pdata->sample);
731 static int __devinit ad2s1210_probe(struct spi_device *spi)
733 struct iio_dev *indio_dev;
734 struct ad2s1210_state *st;
737 if (spi->dev.platform_data == NULL)
740 indio_dev = iio_allocate_device(sizeof(*st));
741 if (indio_dev == NULL) {
745 st = iio_priv(indio_dev);
746 st->pdata = spi->dev.platform_data;
747 ret = ad2s1210_setup_gpios(st);
751 spi_set_drvdata(spi, indio_dev);
753 mutex_init(&st->lock);
755 st->hysteresis = true;
756 st->mode = MOD_CONFIG;
758 st->fexcit = AD2S1210_DEF_EXCIT;
760 indio_dev->dev.parent = &spi->dev;
761 indio_dev->info = &ad2s1210_info;
762 indio_dev->modes = INDIO_DIRECT_MODE;
764 ret = iio_device_register(indio_dev);
766 goto error_free_gpios;
768 st->fclkin = spi->max_speed_hz;
769 spi->mode = SPI_MODE_3;
771 ad2s1210_initial(st);
776 ad2s1210_free_gpios(st);
778 iio_free_device(indio_dev);
783 static int __devexit ad2s1210_remove(struct spi_device *spi)
785 struct iio_dev *indio_dev = spi_get_drvdata(spi);
786 struct ad2s1210_state *st = iio_priv(indio_dev);
787 ad2s1210_free_gpios(st);
788 iio_device_unregister(indio_dev);
793 static struct spi_driver ad2s1210_driver = {
796 .owner = THIS_MODULE,
798 .probe = ad2s1210_probe,
799 .remove = __devexit_p(ad2s1210_remove),
802 static __init int ad2s1210_spi_init(void)
804 return spi_register_driver(&ad2s1210_driver);
806 module_init(ad2s1210_spi_init);
808 static __exit void ad2s1210_spi_exit(void)
810 spi_unregister_driver(&ad2s1210_driver);
812 module_exit(ad2s1210_spi_exit);
814 MODULE_AUTHOR("Graff Yang <graff.yang@gmail.com>");
815 MODULE_DESCRIPTION("Analog Devices AD2S1210 Resolver to Digital SPI driver");
816 MODULE_LICENSE("GPL v2");