gpio-davinci.c 16 KB

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  1. /*
  2. * TI DaVinci GPIO Support
  3. *
  4. * Copyright (c) 2006-2007 David Brownell
  5. * Copyright (c) 2007, MontaVista Software, Inc. <source@mvista.com>
  6. *
  7. * This program is free software; you can redistribute it and/or modify
  8. * it under the terms of the GNU General Public License as published by
  9. * the Free Software Foundation; either version 2 of the License, or
  10. * (at your option) any later version.
  11. */
  12. #include <linux/gpio.h>
  13. #include <linux/errno.h>
  14. #include <linux/kernel.h>
  15. #include <linux/clk.h>
  16. #include <linux/err.h>
  17. #include <linux/io.h>
  18. #include <linux/irq.h>
  19. #include <linux/irqdomain.h>
  20. #include <linux/module.h>
  21. #include <linux/of.h>
  22. #include <linux/of_device.h>
  23. #include <linux/platform_device.h>
  24. #include <linux/platform_data/gpio-davinci.h>
  25. #include <linux/irqchip/chained_irq.h>
  26. struct davinci_gpio_regs {
  27. u32 dir;
  28. u32 out_data;
  29. u32 set_data;
  30. u32 clr_data;
  31. u32 in_data;
  32. u32 set_rising;
  33. u32 clr_rising;
  34. u32 set_falling;
  35. u32 clr_falling;
  36. u32 intstat;
  37. };
  38. typedef struct irq_chip *(*gpio_get_irq_chip_cb_t)(unsigned int irq);
  39. #define BINTEN 0x8 /* GPIO Interrupt Per-Bank Enable Register */
  40. static void __iomem *gpio_base;
  41. static unsigned int offset_array[5] = {0x10, 0x38, 0x60, 0x88, 0xb0};
  42. static inline struct davinci_gpio_regs __iomem *irq2regs(struct irq_data *d)
  43. {
  44. struct davinci_gpio_regs __iomem *g;
  45. g = (__force struct davinci_gpio_regs __iomem *)irq_data_get_irq_chip_data(d);
  46. return g;
  47. }
  48. static int davinci_gpio_irq_setup(struct platform_device *pdev);
  49. /*--------------------------------------------------------------------------*/
  50. /* board setup code *MUST* setup pinmux and enable the GPIO clock. */
  51. static inline int __davinci_direction(struct gpio_chip *chip,
  52. unsigned offset, bool out, int value)
  53. {
  54. struct davinci_gpio_controller *d = gpiochip_get_data(chip);
  55. struct davinci_gpio_regs __iomem *g;
  56. unsigned long flags;
  57. u32 temp;
  58. int bank = offset / 32;
  59. u32 mask = __gpio_mask(offset);
  60. g = d->regs[bank];
  61. spin_lock_irqsave(&d->lock, flags);
  62. temp = readl_relaxed(&g->dir);
  63. if (out) {
  64. temp &= ~mask;
  65. writel_relaxed(mask, value ? &g->set_data : &g->clr_data);
  66. } else {
  67. temp |= mask;
  68. }
  69. writel_relaxed(temp, &g->dir);
  70. spin_unlock_irqrestore(&d->lock, flags);
  71. return 0;
  72. }
  73. static int davinci_direction_in(struct gpio_chip *chip, unsigned offset)
  74. {
  75. return __davinci_direction(chip, offset, false, 0);
  76. }
  77. static int
  78. davinci_direction_out(struct gpio_chip *chip, unsigned offset, int value)
  79. {
  80. return __davinci_direction(chip, offset, true, value);
  81. }
  82. /*
  83. * Read the pin's value (works even if it's set up as output);
  84. * returns zero/nonzero.
  85. *
  86. * Note that changes are synched to the GPIO clock, so reading values back
  87. * right after you've set them may give old values.
  88. */
  89. static int davinci_gpio_get(struct gpio_chip *chip, unsigned offset)
  90. {
  91. struct davinci_gpio_controller *d = gpiochip_get_data(chip);
  92. struct davinci_gpio_regs __iomem *g;
  93. int bank = offset / 32;
  94. g = d->regs[bank];
  95. return !!(__gpio_mask(offset) & readl_relaxed(&g->in_data));
  96. }
  97. /*
  98. * Assuming the pin is muxed as a gpio output, set its output value.
  99. */
  100. static void
  101. davinci_gpio_set(struct gpio_chip *chip, unsigned offset, int value)
  102. {
  103. struct davinci_gpio_controller *d = gpiochip_get_data(chip);
  104. struct davinci_gpio_regs __iomem *g;
  105. int bank = offset / 32;
  106. g = d->regs[bank];
  107. writel_relaxed(__gpio_mask(offset),
  108. value ? &g->set_data : &g->clr_data);
  109. }
  110. static struct davinci_gpio_platform_data *
  111. davinci_gpio_get_pdata(struct platform_device *pdev)
  112. {
  113. struct device_node *dn = pdev->dev.of_node;
  114. struct davinci_gpio_platform_data *pdata;
  115. int ret;
  116. u32 val;
  117. if (!IS_ENABLED(CONFIG_OF) || !pdev->dev.of_node)
  118. return dev_get_platdata(&pdev->dev);
  119. pdata = devm_kzalloc(&pdev->dev, sizeof(*pdata), GFP_KERNEL);
  120. if (!pdata)
  121. return NULL;
  122. ret = of_property_read_u32(dn, "ti,ngpio", &val);
  123. if (ret)
  124. goto of_err;
  125. pdata->ngpio = val;
  126. ret = of_property_read_u32(dn, "ti,davinci-gpio-unbanked", &val);
  127. if (ret)
  128. goto of_err;
  129. pdata->gpio_unbanked = val;
  130. return pdata;
  131. of_err:
  132. dev_err(&pdev->dev, "Populating pdata from DT failed: err %d\n", ret);
  133. return NULL;
  134. }
  135. static int davinci_gpio_probe(struct platform_device *pdev)
  136. {
  137. int gpio, bank;
  138. unsigned ngpio, nbank;
  139. struct davinci_gpio_controller *chips;
  140. struct davinci_gpio_platform_data *pdata;
  141. struct device *dev = &pdev->dev;
  142. struct resource *res;
  143. static int bank_base;
  144. pdata = davinci_gpio_get_pdata(pdev);
  145. if (!pdata) {
  146. dev_err(dev, "No platform data found\n");
  147. return -EINVAL;
  148. }
  149. dev->platform_data = pdata;
  150. /*
  151. * The gpio banks conceptually expose a segmented bitmap,
  152. * and "ngpio" is one more than the largest zero-based
  153. * bit index that's valid.
  154. */
  155. ngpio = pdata->ngpio;
  156. if (ngpio == 0) {
  157. dev_err(dev, "How many GPIOs?\n");
  158. return -EINVAL;
  159. }
  160. if (WARN_ON(ARCH_NR_GPIOS < ngpio))
  161. ngpio = ARCH_NR_GPIOS;
  162. nbank = DIV_ROUND_UP(ngpio, 32);
  163. chips = devm_kzalloc(dev,
  164. nbank * sizeof(struct davinci_gpio_controller),
  165. GFP_KERNEL);
  166. if (!chips)
  167. return -ENOMEM;
  168. res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
  169. gpio_base = devm_ioremap_resource(dev, res);
  170. if (IS_ERR(gpio_base))
  171. return PTR_ERR(gpio_base);
  172. chips->chip.label = "Davinci";
  173. chips->chip.direction_input = davinci_direction_in;
  174. chips->chip.get = davinci_gpio_get;
  175. chips->chip.direction_output = davinci_direction_out;
  176. chips->chip.set = davinci_gpio_set;
  177. chips->chip.ngpio = ngpio;
  178. chips->chip.base = bank_base;
  179. #ifdef CONFIG_OF_GPIO
  180. chips->chip.of_gpio_n_cells = 2;
  181. chips->chip.parent = dev;
  182. chips->chip.of_node = dev->of_node;
  183. #endif
  184. spin_lock_init(&chips->lock);
  185. bank_base += ngpio;
  186. for (gpio = 0, bank = 0; gpio < ngpio; gpio += 32, bank++)
  187. chips->regs[bank] = gpio_base + offset_array[bank];
  188. gpiochip_add_data(&chips->chip, chips);
  189. platform_set_drvdata(pdev, chips);
  190. davinci_gpio_irq_setup(pdev);
  191. return 0;
  192. }
  193. /*--------------------------------------------------------------------------*/
  194. /*
  195. * We expect irqs will normally be set up as input pins, but they can also be
  196. * used as output pins ... which is convenient for testing.
  197. *
  198. * NOTE: The first few GPIOs also have direct INTC hookups in addition
  199. * to their GPIOBNK0 irq, with a bit less overhead.
  200. *
  201. * All those INTC hookups (direct, plus several IRQ banks) can also
  202. * serve as EDMA event triggers.
  203. */
  204. static void gpio_irq_disable(struct irq_data *d)
  205. {
  206. struct davinci_gpio_regs __iomem *g = irq2regs(d);
  207. u32 mask = (u32) irq_data_get_irq_handler_data(d);
  208. writel_relaxed(mask, &g->clr_falling);
  209. writel_relaxed(mask, &g->clr_rising);
  210. }
  211. static void gpio_irq_enable(struct irq_data *d)
  212. {
  213. struct davinci_gpio_regs __iomem *g = irq2regs(d);
  214. u32 mask = (u32) irq_data_get_irq_handler_data(d);
  215. unsigned status = irqd_get_trigger_type(d);
  216. status &= IRQ_TYPE_EDGE_FALLING | IRQ_TYPE_EDGE_RISING;
  217. if (!status)
  218. status = IRQ_TYPE_EDGE_FALLING | IRQ_TYPE_EDGE_RISING;
  219. if (status & IRQ_TYPE_EDGE_FALLING)
  220. writel_relaxed(mask, &g->set_falling);
  221. if (status & IRQ_TYPE_EDGE_RISING)
  222. writel_relaxed(mask, &g->set_rising);
  223. }
  224. static int gpio_irq_type(struct irq_data *d, unsigned trigger)
  225. {
  226. if (trigger & ~(IRQ_TYPE_EDGE_FALLING | IRQ_TYPE_EDGE_RISING))
  227. return -EINVAL;
  228. return 0;
  229. }
  230. static struct irq_chip gpio_irqchip = {
  231. .name = "GPIO",
  232. .irq_enable = gpio_irq_enable,
  233. .irq_disable = gpio_irq_disable,
  234. .irq_set_type = gpio_irq_type,
  235. .flags = IRQCHIP_SET_TYPE_MASKED,
  236. };
  237. static void gpio_irq_handler(struct irq_desc *desc)
  238. {
  239. struct davinci_gpio_regs __iomem *g;
  240. u32 mask = 0xffff;
  241. int bank_num;
  242. struct davinci_gpio_controller *d;
  243. struct davinci_gpio_irq_data *irqdata;
  244. irqdata = (struct davinci_gpio_irq_data *)irq_desc_get_handler_data(desc);
  245. bank_num = irqdata->bank_num;
  246. g = irqdata->regs;
  247. d = irqdata->chip;
  248. /* we only care about one bank */
  249. if ((bank_num % 2) == 1)
  250. mask <<= 16;
  251. /* temporarily mask (level sensitive) parent IRQ */
  252. chained_irq_enter(irq_desc_get_chip(desc), desc);
  253. while (1) {
  254. u32 status;
  255. int bit;
  256. irq_hw_number_t hw_irq;
  257. /* ack any irqs */
  258. status = readl_relaxed(&g->intstat) & mask;
  259. if (!status)
  260. break;
  261. writel_relaxed(status, &g->intstat);
  262. /* now demux them to the right lowlevel handler */
  263. while (status) {
  264. bit = __ffs(status);
  265. status &= ~BIT(bit);
  266. /* Max number of gpios per controller is 144 so
  267. * hw_irq will be in [0..143]
  268. */
  269. hw_irq = (bank_num / 2) * 32 + bit;
  270. generic_handle_irq(
  271. irq_find_mapping(d->irq_domain, hw_irq));
  272. }
  273. }
  274. chained_irq_exit(irq_desc_get_chip(desc), desc);
  275. /* now it may re-trigger */
  276. }
  277. static int gpio_to_irq_banked(struct gpio_chip *chip, unsigned offset)
  278. {
  279. struct davinci_gpio_controller *d = gpiochip_get_data(chip);
  280. if (d->irq_domain)
  281. return irq_create_mapping(d->irq_domain, offset);
  282. else
  283. return -ENXIO;
  284. }
  285. static int gpio_to_irq_unbanked(struct gpio_chip *chip, unsigned offset)
  286. {
  287. struct davinci_gpio_controller *d = gpiochip_get_data(chip);
  288. /*
  289. * NOTE: we assume for now that only irqs in the first gpio_chip
  290. * can provide direct-mapped IRQs to AINTC (up to 32 GPIOs).
  291. */
  292. if (offset < d->gpio_unbanked)
  293. return d->base_irq + offset;
  294. else
  295. return -ENODEV;
  296. }
  297. static int gpio_irq_type_unbanked(struct irq_data *data, unsigned trigger)
  298. {
  299. struct davinci_gpio_controller *d;
  300. struct davinci_gpio_regs __iomem *g;
  301. u32 mask;
  302. d = (struct davinci_gpio_controller *)irq_data_get_irq_handler_data(data);
  303. g = (struct davinci_gpio_regs __iomem *)d->regs[0];
  304. mask = __gpio_mask(data->irq - d->base_irq);
  305. if (trigger & ~(IRQ_TYPE_EDGE_FALLING | IRQ_TYPE_EDGE_RISING))
  306. return -EINVAL;
  307. writel_relaxed(mask, (trigger & IRQ_TYPE_EDGE_FALLING)
  308. ? &g->set_falling : &g->clr_falling);
  309. writel_relaxed(mask, (trigger & IRQ_TYPE_EDGE_RISING)
  310. ? &g->set_rising : &g->clr_rising);
  311. return 0;
  312. }
  313. static int
  314. davinci_gpio_irq_map(struct irq_domain *d, unsigned int irq,
  315. irq_hw_number_t hw)
  316. {
  317. struct davinci_gpio_controller *chips =
  318. (struct davinci_gpio_controller *)d->host_data;
  319. struct davinci_gpio_regs __iomem *g = chips->regs[hw / 32];
  320. irq_set_chip_and_handler_name(irq, &gpio_irqchip, handle_simple_irq,
  321. "davinci_gpio");
  322. irq_set_irq_type(irq, IRQ_TYPE_NONE);
  323. irq_set_chip_data(irq, (__force void *)g);
  324. irq_set_handler_data(irq, (void *)__gpio_mask(hw));
  325. return 0;
  326. }
  327. static const struct irq_domain_ops davinci_gpio_irq_ops = {
  328. .map = davinci_gpio_irq_map,
  329. .xlate = irq_domain_xlate_onetwocell,
  330. };
  331. static struct irq_chip *davinci_gpio_get_irq_chip(unsigned int irq)
  332. {
  333. static struct irq_chip_type gpio_unbanked;
  334. gpio_unbanked = *irq_data_get_chip_type(irq_get_irq_data(irq));
  335. return &gpio_unbanked.chip;
  336. };
  337. static struct irq_chip *keystone_gpio_get_irq_chip(unsigned int irq)
  338. {
  339. static struct irq_chip gpio_unbanked;
  340. gpio_unbanked = *irq_get_chip(irq);
  341. return &gpio_unbanked;
  342. };
  343. static const struct of_device_id davinci_gpio_ids[];
  344. struct gpio_driver_data {
  345. gpio_get_irq_chip_cb_t gpio_get_irq_chip;
  346. bool clk_optional;
  347. };
  348. static struct gpio_driver_data davinci_data = {
  349. .gpio_get_irq_chip = davinci_gpio_get_irq_chip,
  350. .clk_optional = false,
  351. };
  352. static struct gpio_driver_data keystone_data = {
  353. .gpio_get_irq_chip = keystone_gpio_get_irq_chip,
  354. .clk_optional = false,
  355. };
  356. static struct gpio_driver_data k2g_data = {
  357. .gpio_get_irq_chip = keystone_gpio_get_irq_chip,
  358. .clk_optional = true,
  359. };
  360. /*
  361. * NOTE: for suspend/resume, probably best to make a platform_device with
  362. * suspend_late/resume_resume calls hooking into results of the set_wake()
  363. * calls ... so if no gpios are wakeup events the clock can be disabled,
  364. * with outputs left at previously set levels, and so that VDD3P3V.IOPWDN0
  365. * (dm6446) can be set appropriately for GPIOV33 pins.
  366. */
  367. static int davinci_gpio_irq_setup(struct platform_device *pdev)
  368. {
  369. unsigned gpio, bank;
  370. int irq;
  371. struct clk *clk;
  372. u32 binten = 0;
  373. unsigned ngpio, bank_irq;
  374. struct device *dev = &pdev->dev;
  375. struct resource *res;
  376. struct davinci_gpio_controller *chips = platform_get_drvdata(pdev);
  377. struct davinci_gpio_platform_data *pdata = dev->platform_data;
  378. struct davinci_gpio_regs __iomem *g;
  379. struct irq_domain *irq_domain = NULL;
  380. const struct of_device_id *match;
  381. struct irq_chip *irq_chip;
  382. struct davinci_gpio_irq_data *irqdata;
  383. struct gpio_driver_data *driver_data = NULL;
  384. gpio_get_irq_chip_cb_t gpio_get_irq_chip;
  385. /*
  386. * Use davinci_gpio_get_irq_chip by default to handle non DT cases
  387. */
  388. gpio_get_irq_chip = davinci_gpio_get_irq_chip;
  389. match = of_match_device(of_match_ptr(davinci_gpio_ids),
  390. dev);
  391. if (match) {
  392. driver_data = (struct gpio_driver_data *)match->data;
  393. gpio_get_irq_chip = driver_data->gpio_get_irq_chip;
  394. }
  395. ngpio = pdata->ngpio;
  396. res = platform_get_resource(pdev, IORESOURCE_IRQ, 0);
  397. if (!res) {
  398. dev_err(dev, "Invalid IRQ resource\n");
  399. return -EBUSY;
  400. }
  401. bank_irq = res->start;
  402. if (!bank_irq) {
  403. dev_err(dev, "Invalid IRQ resource\n");
  404. return -ENODEV;
  405. }
  406. if (driver_data && driver_data->clk_optional)
  407. goto skip_clk_handling;
  408. clk = devm_clk_get(dev, "gpio");
  409. if (IS_ERR(clk)) {
  410. printk(KERN_ERR "Error %ld getting gpio clock?\n",
  411. PTR_ERR(clk));
  412. return PTR_ERR(clk);
  413. }
  414. clk_prepare_enable(clk);
  415. skip_clk_handling:
  416. if (!pdata->gpio_unbanked) {
  417. irq = irq_alloc_descs(-1, 0, ngpio, 0);
  418. if (irq < 0) {
  419. dev_err(dev, "Couldn't allocate IRQ numbers\n");
  420. return irq;
  421. }
  422. irq_domain = irq_domain_add_legacy(dev->of_node, ngpio, irq, 0,
  423. &davinci_gpio_irq_ops,
  424. chips);
  425. if (!irq_domain) {
  426. dev_err(dev, "Couldn't register an IRQ domain\n");
  427. return -ENODEV;
  428. }
  429. }
  430. /*
  431. * Arrange gpio_to_irq() support, handling either direct IRQs or
  432. * banked IRQs. Having GPIOs in the first GPIO bank use direct
  433. * IRQs, while the others use banked IRQs, would need some setup
  434. * tweaks to recognize hardware which can do that.
  435. */
  436. chips->chip.to_irq = gpio_to_irq_banked;
  437. chips->irq_domain = irq_domain;
  438. /*
  439. * AINTC can handle direct/unbanked IRQs for GPIOs, with the GPIO
  440. * controller only handling trigger modes. We currently assume no
  441. * IRQ mux conflicts; gpio_irq_type_unbanked() is only for GPIOs.
  442. */
  443. if (pdata->gpio_unbanked) {
  444. /* pass "bank 0" GPIO IRQs to AINTC */
  445. chips->chip.to_irq = gpio_to_irq_unbanked;
  446. chips->base_irq = bank_irq;
  447. chips->gpio_unbanked = pdata->gpio_unbanked;
  448. binten = GENMASK(pdata->gpio_unbanked / 16, 0);
  449. /* AINTC handles mask/unmask; GPIO handles triggering */
  450. irq = bank_irq;
  451. irq_chip = gpio_get_irq_chip(irq);
  452. irq_chip->name = "GPIO-AINTC";
  453. irq_chip->irq_set_type = gpio_irq_type_unbanked;
  454. /* default trigger: both edges */
  455. g = chips->regs[0];
  456. writel_relaxed(~0, &g->set_falling);
  457. writel_relaxed(~0, &g->set_rising);
  458. /* set the direct IRQs up to use that irqchip */
  459. for (gpio = 0; gpio < pdata->gpio_unbanked; gpio++, irq++) {
  460. irq_set_chip(irq, irq_chip);
  461. irq_set_handler_data(irq, chips);
  462. irq_set_status_flags(irq, IRQ_TYPE_EDGE_BOTH);
  463. }
  464. goto done;
  465. }
  466. /*
  467. * Or, AINTC can handle IRQs for banks of 16 GPIO IRQs, which we
  468. * then chain through our own handler.
  469. */
  470. for (gpio = 0, bank = 0; gpio < ngpio; bank++, bank_irq++, gpio += 16) {
  471. /* disabled by default, enabled only as needed */
  472. g = chips->regs[bank / 2];
  473. writel_relaxed(~0, &g->clr_falling);
  474. writel_relaxed(~0, &g->clr_rising);
  475. /*
  476. * Each chip handles 32 gpios, and each irq bank consists of 16
  477. * gpio irqs. Pass the irq bank's corresponding controller to
  478. * the chained irq handler.
  479. */
  480. irqdata = devm_kzalloc(&pdev->dev,
  481. sizeof(struct
  482. davinci_gpio_irq_data),
  483. GFP_KERNEL);
  484. if (!irqdata)
  485. return -ENOMEM;
  486. irqdata->regs = g;
  487. irqdata->bank_num = bank;
  488. irqdata->chip = chips;
  489. irq_set_chained_handler_and_data(bank_irq, gpio_irq_handler,
  490. irqdata);
  491. binten |= BIT(bank);
  492. }
  493. done:
  494. /*
  495. * BINTEN -- per-bank interrupt enable. genirq would also let these
  496. * bits be set/cleared dynamically.
  497. */
  498. writel_relaxed(binten, gpio_base + BINTEN);
  499. return 0;
  500. }
  501. #if IS_ENABLED(CONFIG_OF)
  502. static const struct of_device_id davinci_gpio_ids[] = {
  503. {
  504. .compatible = "ti,keystone-gpio",
  505. .data = &keystone_data,
  506. },
  507. {
  508. .compatible = "ti,dm6441-gpio",
  509. .data = &davinci_data,
  510. },
  511. {
  512. .compatible = "ti,k2g-gpio",
  513. .data = &k2g_data,
  514. },
  515. { /* sentinel */ },
  516. };
  517. MODULE_DEVICE_TABLE(of, davinci_gpio_ids);
  518. #endif
  519. static struct platform_driver davinci_gpio_driver = {
  520. .probe = davinci_gpio_probe,
  521. .driver = {
  522. .name = "davinci_gpio",
  523. .of_match_table = of_match_ptr(davinci_gpio_ids),
  524. },
  525. };
  526. /**
  527. * GPIO driver registration needs to be done before machine_init functions
  528. * access GPIO. Hence davinci_gpio_drv_reg() is a postcore_initcall.
  529. */
  530. static int __init davinci_gpio_drv_reg(void)
  531. {
  532. return platform_driver_register(&davinci_gpio_driver);
  533. }
  534. postcore_initcall(davinci_gpio_drv_reg);