/drivers/staging/iio/accel/sca3000_core.c

https://bitbucket.org/wisechild/galaxy-nexus · C · 1272 lines · 968 code · 130 blank · 174 comment · 119 complexity · 05581f1ae65d1ff83c446e689079ab58 MD5 · raw file

  1. /*
  2. * sca3000_core.c -- support VTI sca3000 series accelerometers via SPI
  3. *
  4. * This program is free software; you can redistribute it and/or modify it
  5. * under the terms of the GNU General Public License version 2 as published by
  6. * the Free Software Foundation.
  7. *
  8. * Copyright (c) 2009 Jonathan Cameron <jic23@cam.ac.uk>
  9. *
  10. * See industrialio/accels/sca3000.h for comments.
  11. */
  12. #include <linux/interrupt.h>
  13. #include <linux/gpio.h>
  14. #include <linux/fs.h>
  15. #include <linux/device.h>
  16. #include <linux/slab.h>
  17. #include <linux/kernel.h>
  18. #include <linux/spi/spi.h>
  19. #include <linux/sysfs.h>
  20. #include "../iio.h"
  21. #include "../sysfs.h"
  22. #include "../ring_generic.h"
  23. #include "accel.h"
  24. #include "sca3000.h"
  25. enum sca3000_variant {
  26. d01,
  27. e02,
  28. e04,
  29. e05,
  30. };
  31. /* Note where option modes are not defined, the chip simply does not
  32. * support any.
  33. * Other chips in the sca3000 series use i2c and are not included here.
  34. *
  35. * Some of these devices are only listed in the family data sheet and
  36. * do not actually appear to be available.
  37. */
  38. static const struct sca3000_chip_info sca3000_spi_chip_info_tbl[] = {
  39. [d01] = {
  40. .scale = 7357,
  41. .temp_output = true,
  42. .measurement_mode_freq = 250,
  43. .option_mode_1 = SCA3000_OP_MODE_BYPASS,
  44. .option_mode_1_freq = 250,
  45. .mot_det_mult_xz = {50, 100, 200, 350, 650, 1300},
  46. .mot_det_mult_y = {50, 100, 150, 250, 450, 850, 1750},
  47. },
  48. [e02] = {
  49. .scale = 9810,
  50. .measurement_mode_freq = 125,
  51. .option_mode_1 = SCA3000_OP_MODE_NARROW,
  52. .option_mode_1_freq = 63,
  53. .mot_det_mult_xz = {100, 150, 300, 550, 1050, 2050},
  54. .mot_det_mult_y = {50, 100, 200, 350, 700, 1350, 2700},
  55. },
  56. [e04] = {
  57. .scale = 19620,
  58. .measurement_mode_freq = 100,
  59. .option_mode_1 = SCA3000_OP_MODE_NARROW,
  60. .option_mode_1_freq = 50,
  61. .option_mode_2 = SCA3000_OP_MODE_WIDE,
  62. .option_mode_2_freq = 400,
  63. .mot_det_mult_xz = {200, 300, 600, 1100, 2100, 4100},
  64. .mot_det_mult_y = {100, 200, 400, 7000, 1400, 2700, 54000},
  65. },
  66. [e05] = {
  67. .scale = 61313,
  68. .measurement_mode_freq = 200,
  69. .option_mode_1 = SCA3000_OP_MODE_NARROW,
  70. .option_mode_1_freq = 50,
  71. .option_mode_2 = SCA3000_OP_MODE_WIDE,
  72. .option_mode_2_freq = 400,
  73. .mot_det_mult_xz = {600, 900, 1700, 3200, 6100, 11900},
  74. .mot_det_mult_y = {300, 600, 1200, 2000, 4100, 7800, 15600},
  75. },
  76. };
  77. int sca3000_write_reg(struct sca3000_state *st, u8 address, u8 val)
  78. {
  79. st->tx[0] = SCA3000_WRITE_REG(address);
  80. st->tx[1] = val;
  81. return spi_write(st->us, st->tx, 2);
  82. }
  83. int sca3000_read_data_short(struct sca3000_state *st,
  84. uint8_t reg_address_high,
  85. int len)
  86. {
  87. struct spi_message msg;
  88. struct spi_transfer xfer[2] = {
  89. {
  90. .len = 1,
  91. .tx_buf = st->tx,
  92. }, {
  93. .len = len,
  94. .rx_buf = st->rx,
  95. }
  96. };
  97. st->tx[0] = SCA3000_READ_REG(reg_address_high);
  98. spi_message_init(&msg);
  99. spi_message_add_tail(&xfer[0], &msg);
  100. spi_message_add_tail(&xfer[1], &msg);
  101. return spi_sync(st->us, &msg);
  102. }
  103. /**
  104. * sca3000_reg_lock_on() test if the ctrl register lock is on
  105. *
  106. * Lock must be held.
  107. **/
  108. static int sca3000_reg_lock_on(struct sca3000_state *st)
  109. {
  110. int ret;
  111. ret = sca3000_read_data_short(st, SCA3000_REG_ADDR_STATUS, 1);
  112. if (ret < 0)
  113. return ret;
  114. return !(st->rx[0] & SCA3000_LOCKED);
  115. }
  116. /**
  117. * __sca3000_unlock_reg_lock() unlock the control registers
  118. *
  119. * Note the device does not appear to support doing this in a single transfer.
  120. * This should only ever be used as part of ctrl reg read.
  121. * Lock must be held before calling this
  122. **/
  123. static int __sca3000_unlock_reg_lock(struct sca3000_state *st)
  124. {
  125. struct spi_message msg;
  126. struct spi_transfer xfer[3] = {
  127. {
  128. .len = 2,
  129. .cs_change = 1,
  130. .tx_buf = st->tx,
  131. }, {
  132. .len = 2,
  133. .cs_change = 1,
  134. .tx_buf = st->tx + 2,
  135. }, {
  136. .len = 2,
  137. .tx_buf = st->tx + 4,
  138. },
  139. };
  140. st->tx[0] = SCA3000_WRITE_REG(SCA3000_REG_ADDR_UNLOCK);
  141. st->tx[1] = 0x00;
  142. st->tx[2] = SCA3000_WRITE_REG(SCA3000_REG_ADDR_UNLOCK);
  143. st->tx[3] = 0x50;
  144. st->tx[4] = SCA3000_WRITE_REG(SCA3000_REG_ADDR_UNLOCK);
  145. st->tx[5] = 0xA0;
  146. spi_message_init(&msg);
  147. spi_message_add_tail(&xfer[0], &msg);
  148. spi_message_add_tail(&xfer[1], &msg);
  149. spi_message_add_tail(&xfer[2], &msg);
  150. return spi_sync(st->us, &msg);
  151. }
  152. /**
  153. * sca3000_write_ctrl_reg() write to a lock protect ctrl register
  154. * @sel: selects which registers we wish to write to
  155. * @val: the value to be written
  156. *
  157. * Certain control registers are protected against overwriting by the lock
  158. * register and use a shared write address. This function allows writing of
  159. * these registers.
  160. * Lock must be held.
  161. **/
  162. static int sca3000_write_ctrl_reg(struct sca3000_state *st,
  163. uint8_t sel,
  164. uint8_t val)
  165. {
  166. int ret;
  167. ret = sca3000_reg_lock_on(st);
  168. if (ret < 0)
  169. goto error_ret;
  170. if (ret) {
  171. ret = __sca3000_unlock_reg_lock(st);
  172. if (ret)
  173. goto error_ret;
  174. }
  175. /* Set the control select register */
  176. ret = sca3000_write_reg(st, SCA3000_REG_ADDR_CTRL_SEL, sel);
  177. if (ret)
  178. goto error_ret;
  179. /* Write the actual value into the register */
  180. ret = sca3000_write_reg(st, SCA3000_REG_ADDR_CTRL_DATA, val);
  181. error_ret:
  182. return ret;
  183. }
  184. /* Crucial that lock is called before calling this */
  185. /**
  186. * sca3000_read_ctrl_reg() read from lock protected control register.
  187. *
  188. * Lock must be held.
  189. **/
  190. static int sca3000_read_ctrl_reg(struct sca3000_state *st,
  191. u8 ctrl_reg)
  192. {
  193. int ret;
  194. ret = sca3000_reg_lock_on(st);
  195. if (ret < 0)
  196. goto error_ret;
  197. if (ret) {
  198. ret = __sca3000_unlock_reg_lock(st);
  199. if (ret)
  200. goto error_ret;
  201. }
  202. /* Set the control select register */
  203. ret = sca3000_write_reg(st, SCA3000_REG_ADDR_CTRL_SEL, ctrl_reg);
  204. if (ret)
  205. goto error_ret;
  206. ret = sca3000_read_data_short(st, SCA3000_REG_ADDR_CTRL_DATA, 1);
  207. if (ret)
  208. goto error_ret;
  209. else
  210. return st->rx[0];
  211. error_ret:
  212. return ret;
  213. }
  214. #ifdef SCA3000_DEBUG
  215. /**
  216. * sca3000_check_status() check the status register
  217. *
  218. * Only used for debugging purposes
  219. **/
  220. static int sca3000_check_status(struct device *dev)
  221. {
  222. int ret;
  223. struct iio_dev *indio_dev = dev_get_drvdata(dev);
  224. struct sca3000_state *st = indio_dev->dev_data;
  225. mutex_lock(&st->lock);
  226. ret = sca3000_read_data_short(st, SCA3000_REG_ADDR_STATUS, 1);
  227. if (ret < 0)
  228. goto error_ret;
  229. if (st->rx[0] & SCA3000_EEPROM_CS_ERROR)
  230. dev_err(dev, "eeprom error\n");
  231. if (st->rx[0] & SCA3000_SPI_FRAME_ERROR)
  232. dev_err(dev, "Previous SPI Frame was corrupt\n");
  233. error_ret:
  234. mutex_unlock(&st->lock);
  235. return ret;
  236. }
  237. #endif /* SCA3000_DEBUG */
  238. /**
  239. * sca3000_show_reg() - sysfs interface to read the chip revision number
  240. **/
  241. static ssize_t sca3000_show_rev(struct device *dev,
  242. struct device_attribute *attr,
  243. char *buf)
  244. {
  245. int len = 0, ret;
  246. struct iio_dev *dev_info = dev_get_drvdata(dev);
  247. struct sca3000_state *st = dev_info->dev_data;
  248. mutex_lock(&st->lock);
  249. ret = sca3000_read_data_short(st, SCA3000_REG_ADDR_REVID, 1);
  250. if (ret < 0)
  251. goto error_ret;
  252. len += sprintf(buf + len,
  253. "major=%d, minor=%d\n",
  254. st->rx[0] & SCA3000_REVID_MAJOR_MASK,
  255. st->rx[0] & SCA3000_REVID_MINOR_MASK);
  256. error_ret:
  257. mutex_unlock(&st->lock);
  258. return ret ? ret : len;
  259. }
  260. /**
  261. * sca3000_show_available_measurement_modes() display available modes
  262. *
  263. * This is all read from chip specific data in the driver. Not all
  264. * of the sca3000 series support modes other than normal.
  265. **/
  266. static ssize_t
  267. sca3000_show_available_measurement_modes(struct device *dev,
  268. struct device_attribute *attr,
  269. char *buf)
  270. {
  271. struct iio_dev *dev_info = dev_get_drvdata(dev);
  272. struct sca3000_state *st = dev_info->dev_data;
  273. int len = 0;
  274. len += sprintf(buf + len, "0 - normal mode");
  275. switch (st->info->option_mode_1) {
  276. case SCA3000_OP_MODE_NARROW:
  277. len += sprintf(buf + len, ", 1 - narrow mode");
  278. break;
  279. case SCA3000_OP_MODE_BYPASS:
  280. len += sprintf(buf + len, ", 1 - bypass mode");
  281. break;
  282. }
  283. switch (st->info->option_mode_2) {
  284. case SCA3000_OP_MODE_WIDE:
  285. len += sprintf(buf + len, ", 2 - wide mode");
  286. break;
  287. }
  288. /* always supported */
  289. len += sprintf(buf + len, " 3 - motion detection\n");
  290. return len;
  291. }
  292. /**
  293. * sca3000_show_measurmenet_mode() sysfs read of current mode
  294. **/
  295. static ssize_t
  296. sca3000_show_measurement_mode(struct device *dev,
  297. struct device_attribute *attr,
  298. char *buf)
  299. {
  300. struct iio_dev *dev_info = dev_get_drvdata(dev);
  301. struct sca3000_state *st = dev_info->dev_data;
  302. int len = 0, ret;
  303. mutex_lock(&st->lock);
  304. ret = sca3000_read_data_short(st, SCA3000_REG_ADDR_MODE, 1);
  305. if (ret)
  306. goto error_ret;
  307. /* mask bottom 2 bits - only ones that are relevant */
  308. st->rx[0] &= 0x03;
  309. switch (st->rx[0]) {
  310. case SCA3000_MEAS_MODE_NORMAL:
  311. len += sprintf(buf + len, "0 - normal mode\n");
  312. break;
  313. case SCA3000_MEAS_MODE_MOT_DET:
  314. len += sprintf(buf + len, "3 - motion detection\n");
  315. break;
  316. case SCA3000_MEAS_MODE_OP_1:
  317. switch (st->info->option_mode_1) {
  318. case SCA3000_OP_MODE_NARROW:
  319. len += sprintf(buf + len, "1 - narrow mode\n");
  320. break;
  321. case SCA3000_OP_MODE_BYPASS:
  322. len += sprintf(buf + len, "1 - bypass mode\n");
  323. break;
  324. }
  325. break;
  326. case SCA3000_MEAS_MODE_OP_2:
  327. switch (st->info->option_mode_2) {
  328. case SCA3000_OP_MODE_WIDE:
  329. len += sprintf(buf + len, "2 - wide mode\n");
  330. break;
  331. }
  332. break;
  333. }
  334. error_ret:
  335. mutex_unlock(&st->lock);
  336. return ret ? ret : len;
  337. }
  338. /**
  339. * sca3000_store_measurement_mode() set the current mode
  340. **/
  341. static ssize_t
  342. sca3000_store_measurement_mode(struct device *dev,
  343. struct device_attribute *attr,
  344. const char *buf,
  345. size_t len)
  346. {
  347. struct iio_dev *dev_info = dev_get_drvdata(dev);
  348. struct sca3000_state *st = dev_info->dev_data;
  349. int ret;
  350. int mask = 0x03;
  351. long val;
  352. mutex_lock(&st->lock);
  353. ret = strict_strtol(buf, 10, &val);
  354. if (ret)
  355. goto error_ret;
  356. ret = sca3000_read_data_short(st, SCA3000_REG_ADDR_MODE, 1);
  357. if (ret)
  358. goto error_ret;
  359. st->rx[0] &= ~mask;
  360. st->rx[0] |= (val & mask);
  361. ret = sca3000_write_reg(st, SCA3000_REG_ADDR_MODE, st->rx[0]);
  362. if (ret)
  363. goto error_ret;
  364. mutex_unlock(&st->lock);
  365. return len;
  366. error_ret:
  367. mutex_unlock(&st->lock);
  368. return ret;
  369. }
  370. /* Not even vaguely standard attributes so defined here rather than
  371. * in the relevant IIO core headers
  372. */
  373. static IIO_DEVICE_ATTR(measurement_mode_available, S_IRUGO,
  374. sca3000_show_available_measurement_modes,
  375. NULL, 0);
  376. static IIO_DEVICE_ATTR(measurement_mode, S_IRUGO | S_IWUSR,
  377. sca3000_show_measurement_mode,
  378. sca3000_store_measurement_mode,
  379. 0);
  380. /* More standard attributes */
  381. static IIO_DEV_ATTR_REV(sca3000_show_rev);
  382. #define SCA3000_INFO_MASK \
  383. (1 << IIO_CHAN_INFO_SCALE_SHARED)
  384. #define SCA3000_EVENT_MASK \
  385. (IIO_EV_BIT(IIO_EV_TYPE_MAG, IIO_EV_DIR_RISING))
  386. static struct iio_chan_spec sca3000_channels[] = {
  387. IIO_CHAN(IIO_ACCEL, 1, 0, 0, NULL, 0, IIO_MOD_X, SCA3000_INFO_MASK,
  388. 0, 0, IIO_ST('s', 11, 16, 5), SCA3000_EVENT_MASK),
  389. IIO_CHAN(IIO_ACCEL, 1, 0, 0, NULL, 0, IIO_MOD_Y, SCA3000_INFO_MASK,
  390. 1, 1, IIO_ST('s', 11, 16, 5), SCA3000_EVENT_MASK),
  391. IIO_CHAN(IIO_ACCEL, 1, 0, 0, NULL, 0, IIO_MOD_Z, SCA3000_INFO_MASK,
  392. 2, 2, IIO_ST('s', 11, 16, 5), SCA3000_EVENT_MASK),
  393. };
  394. static u8 sca3000_addresses[3][3] = {
  395. [0] = {SCA3000_REG_ADDR_X_MSB, SCA3000_REG_CTRL_SEL_MD_X_TH,
  396. SCA3000_MD_CTRL_OR_X},
  397. [1] = {SCA3000_REG_ADDR_Y_MSB, SCA3000_REG_CTRL_SEL_MD_Y_TH,
  398. SCA3000_MD_CTRL_OR_Y},
  399. [2] = {SCA3000_REG_ADDR_Z_MSB, SCA3000_REG_CTRL_SEL_MD_Z_TH,
  400. SCA3000_MD_CTRL_OR_Z},
  401. };
  402. static int sca3000_read_raw(struct iio_dev *indio_dev,
  403. struct iio_chan_spec const *chan,
  404. int *val,
  405. int *val2,
  406. long mask)
  407. {
  408. struct sca3000_state *st = indio_dev->dev_data;
  409. int ret;
  410. u8 address;
  411. switch (mask) {
  412. case 0:
  413. mutex_lock(&st->lock);
  414. if (st->mo_det_use_count) {
  415. mutex_unlock(&st->lock);
  416. return -EBUSY;
  417. }
  418. address = sca3000_addresses[chan->address][0];
  419. ret = sca3000_read_data_short(st, address, 2);
  420. if (ret < 0) {
  421. mutex_unlock(&st->lock);
  422. return ret;
  423. }
  424. *val = (be16_to_cpup((__be16 *)st->rx) >> 3) & 0x1FFF;
  425. *val = ((*val) << (sizeof(*val)*8 - 13)) >>
  426. (sizeof(*val)*8 - 13);
  427. mutex_unlock(&st->lock);
  428. return IIO_VAL_INT;
  429. case (1 << IIO_CHAN_INFO_SCALE_SHARED):
  430. *val = 0;
  431. if (chan->type == IIO_ACCEL)
  432. *val2 = st->info->scale;
  433. else /* temperature */
  434. *val2 = 555556;
  435. return IIO_VAL_INT_PLUS_MICRO;
  436. default:
  437. return -EINVAL;
  438. }
  439. }
  440. /**
  441. * sca3000_read_av_freq() sysfs function to get available frequencies
  442. *
  443. * The later modes are only relevant to the ring buffer - and depend on current
  444. * mode. Note that data sheet gives rather wide tolerances for these so integer
  445. * division will give good enough answer and not all chips have them specified
  446. * at all.
  447. **/
  448. static ssize_t sca3000_read_av_freq(struct device *dev,
  449. struct device_attribute *attr,
  450. char *buf)
  451. {
  452. struct iio_dev *indio_dev = dev_get_drvdata(dev);
  453. struct sca3000_state *st = indio_dev->dev_data;
  454. int len = 0, ret, val;
  455. mutex_lock(&st->lock);
  456. ret = sca3000_read_data_short(st, SCA3000_REG_ADDR_MODE, 1);
  457. val = st->rx[0];
  458. mutex_unlock(&st->lock);
  459. if (ret)
  460. goto error_ret;
  461. switch (val & 0x03) {
  462. case SCA3000_MEAS_MODE_NORMAL:
  463. len += sprintf(buf + len, "%d %d %d\n",
  464. st->info->measurement_mode_freq,
  465. st->info->measurement_mode_freq/2,
  466. st->info->measurement_mode_freq/4);
  467. break;
  468. case SCA3000_MEAS_MODE_OP_1:
  469. len += sprintf(buf + len, "%d %d %d\n",
  470. st->info->option_mode_1_freq,
  471. st->info->option_mode_1_freq/2,
  472. st->info->option_mode_1_freq/4);
  473. break;
  474. case SCA3000_MEAS_MODE_OP_2:
  475. len += sprintf(buf + len, "%d %d %d\n",
  476. st->info->option_mode_2_freq,
  477. st->info->option_mode_2_freq/2,
  478. st->info->option_mode_2_freq/4);
  479. break;
  480. }
  481. return len;
  482. error_ret:
  483. return ret;
  484. }
  485. /**
  486. * __sca3000_get_base_frequency() obtain mode specific base frequency
  487. *
  488. * lock must be held
  489. **/
  490. static inline int __sca3000_get_base_freq(struct sca3000_state *st,
  491. const struct sca3000_chip_info *info,
  492. int *base_freq)
  493. {
  494. int ret;
  495. ret = sca3000_read_data_short(st, SCA3000_REG_ADDR_MODE, 1);
  496. if (ret)
  497. goto error_ret;
  498. switch (0x03 & st->rx[0]) {
  499. case SCA3000_MEAS_MODE_NORMAL:
  500. *base_freq = info->measurement_mode_freq;
  501. break;
  502. case SCA3000_MEAS_MODE_OP_1:
  503. *base_freq = info->option_mode_1_freq;
  504. break;
  505. case SCA3000_MEAS_MODE_OP_2:
  506. *base_freq = info->option_mode_2_freq;
  507. break;
  508. }
  509. error_ret:
  510. return ret;
  511. }
  512. /**
  513. * sca3000_read_frequency() sysfs interface to get the current frequency
  514. **/
  515. static ssize_t sca3000_read_frequency(struct device *dev,
  516. struct device_attribute *attr,
  517. char *buf)
  518. {
  519. struct iio_dev *indio_dev = dev_get_drvdata(dev);
  520. struct sca3000_state *st = indio_dev->dev_data;
  521. int ret, len = 0, base_freq = 0, val;
  522. mutex_lock(&st->lock);
  523. ret = __sca3000_get_base_freq(st, st->info, &base_freq);
  524. if (ret)
  525. goto error_ret_mut;
  526. ret = sca3000_read_ctrl_reg(st, SCA3000_REG_CTRL_SEL_OUT_CTRL);
  527. mutex_unlock(&st->lock);
  528. if (ret)
  529. goto error_ret;
  530. val = ret;
  531. if (base_freq > 0)
  532. switch (val & 0x03) {
  533. case 0x00:
  534. case 0x03:
  535. len = sprintf(buf, "%d\n", base_freq);
  536. break;
  537. case 0x01:
  538. len = sprintf(buf, "%d\n", base_freq/2);
  539. break;
  540. case 0x02:
  541. len = sprintf(buf, "%d\n", base_freq/4);
  542. break;
  543. }
  544. return len;
  545. error_ret_mut:
  546. mutex_unlock(&st->lock);
  547. error_ret:
  548. return ret;
  549. }
  550. /**
  551. * sca3000_set_frequency() sysfs interface to set the current frequency
  552. **/
  553. static ssize_t sca3000_set_frequency(struct device *dev,
  554. struct device_attribute *attr,
  555. const char *buf,
  556. size_t len)
  557. {
  558. struct iio_dev *indio_dev = dev_get_drvdata(dev);
  559. struct sca3000_state *st = indio_dev->dev_data;
  560. int ret, base_freq = 0;
  561. int ctrlval;
  562. long val;
  563. ret = strict_strtol(buf, 10, &val);
  564. if (ret)
  565. return ret;
  566. mutex_lock(&st->lock);
  567. /* What mode are we in? */
  568. ret = __sca3000_get_base_freq(st, st->info, &base_freq);
  569. if (ret)
  570. goto error_free_lock;
  571. ret = sca3000_read_ctrl_reg(st, SCA3000_REG_CTRL_SEL_OUT_CTRL);
  572. if (ret < 0)
  573. goto error_free_lock;
  574. ctrlval = ret;
  575. /* clear the bits */
  576. ctrlval &= ~0x03;
  577. if (val == base_freq/2) {
  578. ctrlval |= SCA3000_OUT_CTRL_BUF_DIV_2;
  579. } else if (val == base_freq/4) {
  580. ctrlval |= SCA3000_OUT_CTRL_BUF_DIV_4;
  581. } else if (val != base_freq) {
  582. ret = -EINVAL;
  583. goto error_free_lock;
  584. }
  585. ret = sca3000_write_ctrl_reg(st, SCA3000_REG_CTRL_SEL_OUT_CTRL,
  586. ctrlval);
  587. error_free_lock:
  588. mutex_unlock(&st->lock);
  589. return ret ? ret : len;
  590. }
  591. /* Should only really be registered if ring buffer support is compiled in.
  592. * Does no harm however and doing it right would add a fair bit of complexity
  593. */
  594. static IIO_DEV_ATTR_SAMP_FREQ_AVAIL(sca3000_read_av_freq);
  595. static IIO_DEV_ATTR_SAMP_FREQ(S_IWUSR | S_IRUGO,
  596. sca3000_read_frequency,
  597. sca3000_set_frequency);
  598. /**
  599. * sca3000_read_temp() sysfs interface to get the temperature when available
  600. *
  601. * The alignment of data in here is downright odd. See data sheet.
  602. * Converting this into a meaningful value is left to inline functions in
  603. * userspace part of header.
  604. **/
  605. static ssize_t sca3000_read_temp(struct device *dev,
  606. struct device_attribute *attr,
  607. char *buf)
  608. {
  609. struct iio_dev *indio_dev = dev_get_drvdata(dev);
  610. struct sca3000_state *st = indio_dev->dev_data;
  611. int ret;
  612. int val;
  613. ret = sca3000_read_data_short(st, SCA3000_REG_ADDR_TEMP_MSB, 2);
  614. if (ret < 0)
  615. goto error_ret;
  616. val = ((st->rx[0] & 0x3F) << 3) | ((st->rx[1] & 0xE0) >> 5);
  617. return sprintf(buf, "%d\n", val);
  618. error_ret:
  619. return ret;
  620. }
  621. static IIO_DEV_ATTR_TEMP_RAW(sca3000_read_temp);
  622. static IIO_CONST_ATTR_TEMP_SCALE("0.555556");
  623. static IIO_CONST_ATTR_TEMP_OFFSET("-214.6");
  624. /**
  625. * sca3000_read_thresh() - query of a threshold
  626. **/
  627. static int sca3000_read_thresh(struct iio_dev *indio_dev,
  628. int e,
  629. int *val)
  630. {
  631. int ret, i;
  632. struct sca3000_state *st = indio_dev->dev_data;
  633. int num = IIO_EVENT_CODE_EXTRACT_MODIFIER(e);
  634. mutex_lock(&st->lock);
  635. ret = sca3000_read_ctrl_reg(st, sca3000_addresses[num][1]);
  636. mutex_unlock(&st->lock);
  637. if (ret < 0)
  638. return ret;
  639. *val = 0;
  640. if (num == 1)
  641. for_each_set_bit(i, (unsigned long *)&ret,
  642. ARRAY_SIZE(st->info->mot_det_mult_y))
  643. *val += st->info->mot_det_mult_y[i];
  644. else
  645. for_each_set_bit(i, (unsigned long *)&ret,
  646. ARRAY_SIZE(st->info->mot_det_mult_xz))
  647. *val += st->info->mot_det_mult_xz[i];
  648. return 0;
  649. }
  650. /**
  651. * sca3000_write_thresh() control of threshold
  652. **/
  653. static int sca3000_write_thresh(struct iio_dev *indio_dev,
  654. int e,
  655. int val)
  656. {
  657. struct sca3000_state *st = indio_dev->dev_data;
  658. int num = IIO_EVENT_CODE_EXTRACT_MODIFIER(e);
  659. int ret;
  660. int i;
  661. u8 nonlinear = 0;
  662. if (num == 1) {
  663. i = ARRAY_SIZE(st->info->mot_det_mult_y);
  664. while (i > 0)
  665. if (val >= st->info->mot_det_mult_y[--i]) {
  666. nonlinear |= (1 << i);
  667. val -= st->info->mot_det_mult_y[i];
  668. }
  669. } else {
  670. i = ARRAY_SIZE(st->info->mot_det_mult_xz);
  671. while (i > 0)
  672. if (val >= st->info->mot_det_mult_xz[--i]) {
  673. nonlinear |= (1 << i);
  674. val -= st->info->mot_det_mult_xz[i];
  675. }
  676. }
  677. mutex_lock(&st->lock);
  678. ret = sca3000_write_ctrl_reg(st, sca3000_addresses[num][1], nonlinear);
  679. mutex_unlock(&st->lock);
  680. return ret;
  681. }
  682. static struct attribute *sca3000_attributes[] = {
  683. &iio_dev_attr_revision.dev_attr.attr,
  684. &iio_dev_attr_measurement_mode_available.dev_attr.attr,
  685. &iio_dev_attr_measurement_mode.dev_attr.attr,
  686. &iio_dev_attr_sampling_frequency_available.dev_attr.attr,
  687. &iio_dev_attr_sampling_frequency.dev_attr.attr,
  688. NULL,
  689. };
  690. static struct attribute *sca3000_attributes_with_temp[] = {
  691. &iio_dev_attr_revision.dev_attr.attr,
  692. &iio_dev_attr_measurement_mode_available.dev_attr.attr,
  693. &iio_dev_attr_measurement_mode.dev_attr.attr,
  694. &iio_dev_attr_sampling_frequency_available.dev_attr.attr,
  695. &iio_dev_attr_sampling_frequency.dev_attr.attr,
  696. /* Only present if temp sensor is */
  697. &iio_dev_attr_temp_raw.dev_attr.attr,
  698. &iio_const_attr_temp_offset.dev_attr.attr,
  699. &iio_const_attr_temp_scale.dev_attr.attr,
  700. NULL,
  701. };
  702. static const struct attribute_group sca3000_attribute_group = {
  703. .attrs = sca3000_attributes,
  704. };
  705. static const struct attribute_group sca3000_attribute_group_with_temp = {
  706. .attrs = sca3000_attributes_with_temp,
  707. };
  708. /* RING RELATED interrupt handler */
  709. /* depending on event, push to the ring buffer event chrdev or the event one */
  710. /**
  711. * sca3000_event_handler() - handling ring and non ring events
  712. *
  713. * This function is complicated by the fact that the devices can signify ring
  714. * and non ring events via the same interrupt line and they can only
  715. * be distinguished via a read of the relevant status register.
  716. **/
  717. static irqreturn_t sca3000_event_handler(int irq, void *private)
  718. {
  719. struct iio_dev *indio_dev = private;
  720. struct sca3000_state *st;
  721. int ret, val;
  722. s64 last_timestamp = iio_get_time_ns();
  723. st = indio_dev->dev_data;
  724. /* Could lead if badly timed to an extra read of status reg,
  725. * but ensures no interrupt is missed.
  726. */
  727. mutex_lock(&st->lock);
  728. ret = sca3000_read_data_short(st, SCA3000_REG_ADDR_INT_STATUS, 1);
  729. val = st->rx[0];
  730. mutex_unlock(&st->lock);
  731. if (ret)
  732. goto done;
  733. sca3000_ring_int_process(val, st->indio_dev->ring);
  734. if (val & SCA3000_INT_STATUS_FREE_FALL)
  735. iio_push_event(st->indio_dev, 0,
  736. IIO_MOD_EVENT_CODE(IIO_EV_CLASS_ACCEL,
  737. 0,
  738. IIO_EV_MOD_X_AND_Y_AND_Z,
  739. IIO_EV_TYPE_MAG,
  740. IIO_EV_DIR_FALLING),
  741. last_timestamp);
  742. if (val & SCA3000_INT_STATUS_Y_TRIGGER)
  743. iio_push_event(st->indio_dev, 0,
  744. IIO_MOD_EVENT_CODE(IIO_EV_CLASS_ACCEL,
  745. 0,
  746. IIO_EV_MOD_Y,
  747. IIO_EV_TYPE_MAG,
  748. IIO_EV_DIR_RISING),
  749. last_timestamp);
  750. if (val & SCA3000_INT_STATUS_X_TRIGGER)
  751. iio_push_event(st->indio_dev, 0,
  752. IIO_MOD_EVENT_CODE(IIO_EV_CLASS_ACCEL,
  753. 0,
  754. IIO_EV_MOD_X,
  755. IIO_EV_TYPE_MAG,
  756. IIO_EV_DIR_RISING),
  757. last_timestamp);
  758. if (val & SCA3000_INT_STATUS_Z_TRIGGER)
  759. iio_push_event(st->indio_dev, 0,
  760. IIO_MOD_EVENT_CODE(IIO_EV_CLASS_ACCEL,
  761. 0,
  762. IIO_EV_MOD_Z,
  763. IIO_EV_TYPE_MAG,
  764. IIO_EV_DIR_RISING),
  765. last_timestamp);
  766. done:
  767. return IRQ_HANDLED;
  768. }
  769. /**
  770. * sca3000_read_event_config() what events are enabled
  771. **/
  772. static int sca3000_read_event_config(struct iio_dev *indio_dev,
  773. int e)
  774. {
  775. struct sca3000_state *st = indio_dev->dev_data;
  776. int ret;
  777. u8 protect_mask = 0x03;
  778. int num = IIO_EVENT_CODE_EXTRACT_MODIFIER(e);
  779. /* read current value of mode register */
  780. mutex_lock(&st->lock);
  781. ret = sca3000_read_data_short(st, SCA3000_REG_ADDR_MODE, 1);
  782. if (ret)
  783. goto error_ret;
  784. if ((st->rx[0] & protect_mask) != SCA3000_MEAS_MODE_MOT_DET)
  785. ret = 0;
  786. else {
  787. ret = sca3000_read_ctrl_reg(st, SCA3000_REG_CTRL_SEL_MD_CTRL);
  788. if (ret < 0)
  789. goto error_ret;
  790. /* only supporting logical or's for now */
  791. ret = !!(ret & sca3000_addresses[num][2]);
  792. }
  793. error_ret:
  794. mutex_unlock(&st->lock);
  795. return ret;
  796. }
  797. /**
  798. * sca3000_query_free_fall_mode() is free fall mode enabled
  799. **/
  800. static ssize_t sca3000_query_free_fall_mode(struct device *dev,
  801. struct device_attribute *attr,
  802. char *buf)
  803. {
  804. int ret, len;
  805. struct iio_dev *indio_dev = dev_get_drvdata(dev);
  806. struct sca3000_state *st = indio_dev->dev_data;
  807. int val;
  808. mutex_lock(&st->lock);
  809. ret = sca3000_read_data_short(st, SCA3000_REG_ADDR_MODE, 1);
  810. val = st->rx[0];
  811. mutex_unlock(&st->lock);
  812. if (ret < 0)
  813. return ret;
  814. len = sprintf(buf, "%d\n",
  815. !!(val & SCA3000_FREE_FALL_DETECT));
  816. return len;
  817. }
  818. /**
  819. * sca3000_set_free_fall_mode() simple on off control for free fall int
  820. *
  821. * In these chips the free fall detector should send an interrupt if
  822. * the device falls more than 25cm. This has not been tested due
  823. * to fragile wiring.
  824. **/
  825. static ssize_t sca3000_set_free_fall_mode(struct device *dev,
  826. struct device_attribute *attr,
  827. const char *buf,
  828. size_t len)
  829. {
  830. struct iio_dev *indio_dev = dev_get_drvdata(dev);
  831. struct sca3000_state *st = indio_dev->dev_data;
  832. long val;
  833. int ret;
  834. u8 protect_mask = SCA3000_FREE_FALL_DETECT;
  835. mutex_lock(&st->lock);
  836. ret = strict_strtol(buf, 10, &val);
  837. if (ret)
  838. goto error_ret;
  839. /* read current value of mode register */
  840. ret = sca3000_read_data_short(st, SCA3000_REG_ADDR_MODE, 1);
  841. if (ret)
  842. goto error_ret;
  843. /*if off and should be on*/
  844. if (val && !(st->rx[0] & protect_mask))
  845. ret = sca3000_write_reg(st, SCA3000_REG_ADDR_MODE,
  846. (st->rx[0] | SCA3000_FREE_FALL_DETECT));
  847. /* if on and should be off */
  848. else if (!val && (st->rx[0] & protect_mask))
  849. ret = sca3000_write_reg(st, SCA3000_REG_ADDR_MODE,
  850. (st->rx[0] & ~protect_mask));
  851. error_ret:
  852. mutex_unlock(&st->lock);
  853. return ret ? ret : len;
  854. }
  855. /**
  856. * sca3000_set_mo_det() simple on off control for motion detector
  857. *
  858. * This is a per axis control, but enabling any will result in the
  859. * motion detector unit being enabled.
  860. * N.B. enabling motion detector stops normal data acquisition.
  861. * There is a complexity in knowing which mode to return to when
  862. * this mode is disabled. Currently normal mode is assumed.
  863. **/
  864. static int sca3000_write_event_config(struct iio_dev *indio_dev,
  865. int e,
  866. int state)
  867. {
  868. struct sca3000_state *st = indio_dev->dev_data;
  869. int ret, ctrlval;
  870. u8 protect_mask = 0x03;
  871. int num = IIO_EVENT_CODE_EXTRACT_MODIFIER(e);
  872. mutex_lock(&st->lock);
  873. /* First read the motion detector config to find out if
  874. * this axis is on*/
  875. ret = sca3000_read_ctrl_reg(st, SCA3000_REG_CTRL_SEL_MD_CTRL);
  876. if (ret < 0)
  877. goto exit_point;
  878. ctrlval = ret;
  879. /* Off and should be on */
  880. if (state && !(ctrlval & sca3000_addresses[num][2])) {
  881. ret = sca3000_write_ctrl_reg(st,
  882. SCA3000_REG_CTRL_SEL_MD_CTRL,
  883. ctrlval |
  884. sca3000_addresses[num][2]);
  885. if (ret)
  886. goto exit_point;
  887. st->mo_det_use_count++;
  888. } else if (!state && (ctrlval & sca3000_addresses[num][2])) {
  889. ret = sca3000_write_ctrl_reg(st,
  890. SCA3000_REG_CTRL_SEL_MD_CTRL,
  891. ctrlval &
  892. ~(sca3000_addresses[num][2]));
  893. if (ret)
  894. goto exit_point;
  895. st->mo_det_use_count--;
  896. }
  897. /* read current value of mode register */
  898. ret = sca3000_read_data_short(st, SCA3000_REG_ADDR_MODE, 1);
  899. if (ret)
  900. goto exit_point;
  901. /*if off and should be on*/
  902. if ((st->mo_det_use_count)
  903. && ((st->rx[0] & protect_mask) != SCA3000_MEAS_MODE_MOT_DET))
  904. ret = sca3000_write_reg(st, SCA3000_REG_ADDR_MODE,
  905. (st->rx[0] & ~protect_mask)
  906. | SCA3000_MEAS_MODE_MOT_DET);
  907. /* if on and should be off */
  908. else if (!(st->mo_det_use_count)
  909. && ((st->rx[0] & protect_mask) == SCA3000_MEAS_MODE_MOT_DET))
  910. ret = sca3000_write_reg(st, SCA3000_REG_ADDR_MODE,
  911. (st->rx[0] & ~protect_mask));
  912. exit_point:
  913. mutex_unlock(&st->lock);
  914. return ret;
  915. }
  916. /* Free fall detector related event attribute */
  917. static IIO_DEVICE_ATTR_NAMED(accel_xayaz_mag_falling_en,
  918. accel_x&y&z_mag_falling_en,
  919. S_IRUGO | S_IWUSR,
  920. sca3000_query_free_fall_mode,
  921. sca3000_set_free_fall_mode,
  922. 0);
  923. static IIO_CONST_ATTR_NAMED(accel_xayaz_mag_falling_period,
  924. accel_x&y&z_mag_falling_period,
  925. "0.226");
  926. static struct attribute *sca3000_event_attributes[] = {
  927. &iio_dev_attr_accel_xayaz_mag_falling_en.dev_attr.attr,
  928. &iio_const_attr_accel_xayaz_mag_falling_period.dev_attr.attr,
  929. NULL,
  930. };
  931. static struct attribute_group sca3000_event_attribute_group = {
  932. .attrs = sca3000_event_attributes,
  933. };
  934. /**
  935. * sca3000_clean_setup() get the device into a predictable state
  936. *
  937. * Devices use flash memory to store many of the register values
  938. * and hence can come up in somewhat unpredictable states.
  939. * Hence reset everything on driver load.
  940. **/
  941. static int sca3000_clean_setup(struct sca3000_state *st)
  942. {
  943. int ret;
  944. mutex_lock(&st->lock);
  945. /* Ensure all interrupts have been acknowledged */
  946. ret = sca3000_read_data_short(st, SCA3000_REG_ADDR_INT_STATUS, 1);
  947. if (ret)
  948. goto error_ret;
  949. /* Turn off all motion detection channels */
  950. ret = sca3000_read_ctrl_reg(st, SCA3000_REG_CTRL_SEL_MD_CTRL);
  951. if (ret < 0)
  952. goto error_ret;
  953. ret = sca3000_write_ctrl_reg(st, SCA3000_REG_CTRL_SEL_MD_CTRL,
  954. ret & SCA3000_MD_CTRL_PROT_MASK);
  955. if (ret)
  956. goto error_ret;
  957. /* Disable ring buffer */
  958. ret = sca3000_read_ctrl_reg(st, SCA3000_REG_CTRL_SEL_OUT_CTRL);
  959. ret = sca3000_write_ctrl_reg(st, SCA3000_REG_CTRL_SEL_OUT_CTRL,
  960. (ret & SCA3000_OUT_CTRL_PROT_MASK)
  961. | SCA3000_OUT_CTRL_BUF_X_EN
  962. | SCA3000_OUT_CTRL_BUF_Y_EN
  963. | SCA3000_OUT_CTRL_BUF_Z_EN
  964. | SCA3000_OUT_CTRL_BUF_DIV_4);
  965. if (ret)
  966. goto error_ret;
  967. /* Enable interrupts, relevant to mode and set up as active low */
  968. ret = sca3000_read_data_short(st, SCA3000_REG_ADDR_INT_MASK, 1);
  969. if (ret)
  970. goto error_ret;
  971. ret = sca3000_write_reg(st,
  972. SCA3000_REG_ADDR_INT_MASK,
  973. (ret & SCA3000_INT_MASK_PROT_MASK)
  974. | SCA3000_INT_MASK_ACTIVE_LOW);
  975. if (ret)
  976. goto error_ret;
  977. /* Select normal measurement mode, free fall off, ring off */
  978. /* Ring in 12 bit mode - it is fine to overwrite reserved bits 3,5
  979. * as that occurs in one of the example on the datasheet */
  980. ret = sca3000_read_data_short(st, SCA3000_REG_ADDR_MODE, 1);
  981. if (ret)
  982. goto error_ret;
  983. ret = sca3000_write_reg(st, SCA3000_REG_ADDR_MODE,
  984. (st->rx[0] & SCA3000_MODE_PROT_MASK));
  985. st->bpse = 11;
  986. error_ret:
  987. mutex_unlock(&st->lock);
  988. return ret;
  989. }
  990. static const struct iio_info sca3000_info = {
  991. .attrs = &sca3000_attribute_group,
  992. .read_raw = &sca3000_read_raw,
  993. .num_interrupt_lines = 1,
  994. .event_attrs = &sca3000_event_attribute_group,
  995. .read_event_value = &sca3000_read_thresh,
  996. .write_event_value = &sca3000_write_thresh,
  997. .read_event_config = &sca3000_read_event_config,
  998. .write_event_config = &sca3000_write_event_config,
  999. .driver_module = THIS_MODULE,
  1000. };
  1001. static const struct iio_info sca3000_info_with_temp = {
  1002. .attrs = &sca3000_attribute_group_with_temp,
  1003. .read_raw = &sca3000_read_raw,
  1004. .read_event_value = &sca3000_read_thresh,
  1005. .write_event_value = &sca3000_write_thresh,
  1006. .read_event_config = &sca3000_read_event_config,
  1007. .write_event_config = &sca3000_write_event_config,
  1008. .driver_module = THIS_MODULE,
  1009. };
  1010. static int __devinit sca3000_probe(struct spi_device *spi)
  1011. {
  1012. int ret, regdone = 0;
  1013. struct sca3000_state *st;
  1014. st = kzalloc(sizeof(struct sca3000_state), GFP_KERNEL);
  1015. if (st == NULL) {
  1016. ret = -ENOMEM;
  1017. goto error_ret;
  1018. }
  1019. spi_set_drvdata(spi, st);
  1020. st->us = spi;
  1021. mutex_init(&st->lock);
  1022. st->info = &sca3000_spi_chip_info_tbl[spi_get_device_id(spi)
  1023. ->driver_data];
  1024. st->indio_dev = iio_allocate_device(0);
  1025. if (st->indio_dev == NULL) {
  1026. ret = -ENOMEM;
  1027. goto error_clear_st;
  1028. }
  1029. st->indio_dev->dev.parent = &spi->dev;
  1030. st->indio_dev->name = spi_get_device_id(spi)->name;
  1031. if (st->info->temp_output)
  1032. st->indio_dev->info = &sca3000_info_with_temp;
  1033. else {
  1034. st->indio_dev->info = &sca3000_info;
  1035. st->indio_dev->channels = sca3000_channels;
  1036. st->indio_dev->num_channels = ARRAY_SIZE(sca3000_channels);
  1037. }
  1038. st->indio_dev->dev_data = (void *)(st);
  1039. st->indio_dev->modes = INDIO_DIRECT_MODE;
  1040. sca3000_configure_ring(st->indio_dev);
  1041. ret = iio_device_register(st->indio_dev);
  1042. if (ret < 0)
  1043. goto error_free_dev;
  1044. regdone = 1;
  1045. ret = iio_ring_buffer_register_ex(st->indio_dev->ring, 0,
  1046. sca3000_channels,
  1047. ARRAY_SIZE(sca3000_channels));
  1048. if (ret < 0)
  1049. goto error_unregister_dev;
  1050. if (spi->irq && gpio_is_valid(irq_to_gpio(spi->irq)) > 0) {
  1051. ret = request_threaded_irq(spi->irq,
  1052. NULL,
  1053. &sca3000_event_handler,
  1054. IRQF_TRIGGER_FALLING,
  1055. "sca3000",
  1056. st->indio_dev);
  1057. if (ret)
  1058. goto error_unregister_ring;
  1059. }
  1060. sca3000_register_ring_funcs(st->indio_dev);
  1061. ret = sca3000_clean_setup(st);
  1062. if (ret)
  1063. goto error_free_irq;
  1064. return 0;
  1065. error_free_irq:
  1066. if (spi->irq && gpio_is_valid(irq_to_gpio(spi->irq)) > 0)
  1067. free_irq(spi->irq, st->indio_dev);
  1068. error_unregister_ring:
  1069. iio_ring_buffer_unregister(st->indio_dev->ring);
  1070. error_unregister_dev:
  1071. error_free_dev:
  1072. if (regdone)
  1073. iio_device_unregister(st->indio_dev);
  1074. else
  1075. iio_free_device(st->indio_dev);
  1076. error_clear_st:
  1077. kfree(st);
  1078. error_ret:
  1079. return ret;
  1080. }
  1081. static int sca3000_stop_all_interrupts(struct sca3000_state *st)
  1082. {
  1083. int ret;
  1084. mutex_lock(&st->lock);
  1085. ret = sca3000_read_data_short(st, SCA3000_REG_ADDR_INT_MASK, 1);
  1086. if (ret)
  1087. goto error_ret;
  1088. ret = sca3000_write_reg(st, SCA3000_REG_ADDR_INT_MASK,
  1089. (st->rx[0] &
  1090. ~(SCA3000_INT_MASK_RING_THREE_QUARTER |
  1091. SCA3000_INT_MASK_RING_HALF |
  1092. SCA3000_INT_MASK_ALL_INTS)));
  1093. error_ret:
  1094. mutex_unlock(&st->lock);
  1095. return ret;
  1096. }
  1097. static int sca3000_remove(struct spi_device *spi)
  1098. {
  1099. struct sca3000_state *st = spi_get_drvdata(spi);
  1100. struct iio_dev *indio_dev = st->indio_dev;
  1101. int ret;
  1102. /* Must ensure no interrupts can be generated after this!*/
  1103. ret = sca3000_stop_all_interrupts(st);
  1104. if (ret)
  1105. return ret;
  1106. if (spi->irq && gpio_is_valid(irq_to_gpio(spi->irq)) > 0)
  1107. free_irq(spi->irq, indio_dev);
  1108. iio_ring_buffer_unregister(indio_dev->ring);
  1109. sca3000_unconfigure_ring(indio_dev);
  1110. iio_device_unregister(indio_dev);
  1111. kfree(st);
  1112. return 0;
  1113. }
  1114. static const struct spi_device_id sca3000_id[] = {
  1115. {"sca3000_d01", d01},
  1116. {"sca3000_e02", e02},
  1117. {"sca3000_e04", e04},
  1118. {"sca3000_e05", e05},
  1119. {}
  1120. };
  1121. static struct spi_driver sca3000_driver = {
  1122. .driver = {
  1123. .name = "sca3000",
  1124. .owner = THIS_MODULE,
  1125. },
  1126. .probe = sca3000_probe,
  1127. .remove = __devexit_p(sca3000_remove),
  1128. .id_table = sca3000_id,
  1129. };
  1130. static __init int sca3000_init(void)
  1131. {
  1132. return spi_register_driver(&sca3000_driver);
  1133. }
  1134. module_init(sca3000_init);
  1135. static __exit void sca3000_exit(void)
  1136. {
  1137. spi_unregister_driver(&sca3000_driver);
  1138. }
  1139. module_exit(sca3000_exit);
  1140. MODULE_AUTHOR("Jonathan Cameron <jic23@cam.ac.uk>");
  1141. MODULE_DESCRIPTION("VTI SCA3000 Series Accelerometers SPI driver");
  1142. MODULE_LICENSE("GPL v2");