pwrseq_sd8787.c 2.8 KB

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  1. // SPDX-License-Identifier: GPL-2.0-or-later
  2. /*
  3. * pwrseq_sd8787.c - power sequence support for Marvell SD8787 BT + Wifi chip
  4. *
  5. * Copyright (C) 2016 Matt Ranostay <matt@ranostay.consulting>
  6. *
  7. * Based on the original work pwrseq_simple.c
  8. * Copyright (C) 2014 Linaro Ltd
  9. * Author: Ulf Hansson <ulf.hansson@linaro.org>
  10. */
  11. #include <linux/delay.h>
  12. #include <linux/init.h>
  13. #include <linux/kernel.h>
  14. #include <linux/platform_device.h>
  15. #include <linux/module.h>
  16. #include <linux/slab.h>
  17. #include <linux/device.h>
  18. #include <linux/err.h>
  19. #include <linux/gpio/consumer.h>
  20. #include <linux/mmc/host.h>
  21. #include "pwrseq.h"
  22. struct mmc_pwrseq_sd8787 {
  23. struct mmc_pwrseq pwrseq;
  24. struct gpio_desc *reset_gpio;
  25. struct gpio_desc *pwrdn_gpio;
  26. };
  27. #define to_pwrseq_sd8787(p) container_of(p, struct mmc_pwrseq_sd8787, pwrseq)
  28. static void mmc_pwrseq_sd8787_pre_power_on(struct mmc_host *host)
  29. {
  30. struct mmc_pwrseq_sd8787 *pwrseq = to_pwrseq_sd8787(host->pwrseq);
  31. gpiod_set_value_cansleep(pwrseq->reset_gpio, 1);
  32. msleep(300);
  33. gpiod_set_value_cansleep(pwrseq->pwrdn_gpio, 1);
  34. }
  35. static void mmc_pwrseq_sd8787_power_off(struct mmc_host *host)
  36. {
  37. struct mmc_pwrseq_sd8787 *pwrseq = to_pwrseq_sd8787(host->pwrseq);
  38. gpiod_set_value_cansleep(pwrseq->pwrdn_gpio, 0);
  39. gpiod_set_value_cansleep(pwrseq->reset_gpio, 0);
  40. }
  41. static const struct mmc_pwrseq_ops mmc_pwrseq_sd8787_ops = {
  42. .pre_power_on = mmc_pwrseq_sd8787_pre_power_on,
  43. .power_off = mmc_pwrseq_sd8787_power_off,
  44. };
  45. static const struct of_device_id mmc_pwrseq_sd8787_of_match[] = {
  46. { .compatible = "mmc-pwrseq-sd8787",},
  47. {/* sentinel */},
  48. };
  49. MODULE_DEVICE_TABLE(of, mmc_pwrseq_sd8787_of_match);
  50. static int mmc_pwrseq_sd8787_probe(struct platform_device *pdev)
  51. {
  52. struct mmc_pwrseq_sd8787 *pwrseq;
  53. struct device *dev = &pdev->dev;
  54. pwrseq = devm_kzalloc(dev, sizeof(*pwrseq), GFP_KERNEL);
  55. if (!pwrseq)
  56. return -ENOMEM;
  57. pwrseq->pwrdn_gpio = devm_gpiod_get(dev, "powerdown", GPIOD_OUT_LOW);
  58. if (IS_ERR(pwrseq->pwrdn_gpio))
  59. return PTR_ERR(pwrseq->pwrdn_gpio);
  60. pwrseq->reset_gpio = devm_gpiod_get(dev, "reset", GPIOD_OUT_LOW);
  61. if (IS_ERR(pwrseq->reset_gpio))
  62. return PTR_ERR(pwrseq->reset_gpio);
  63. pwrseq->pwrseq.dev = dev;
  64. pwrseq->pwrseq.ops = &mmc_pwrseq_sd8787_ops;
  65. pwrseq->pwrseq.owner = THIS_MODULE;
  66. platform_set_drvdata(pdev, pwrseq);
  67. return mmc_pwrseq_register(&pwrseq->pwrseq);
  68. }
  69. static int mmc_pwrseq_sd8787_remove(struct platform_device *pdev)
  70. {
  71. struct mmc_pwrseq_sd8787 *pwrseq = platform_get_drvdata(pdev);
  72. mmc_pwrseq_unregister(&pwrseq->pwrseq);
  73. return 0;
  74. }
  75. static struct platform_driver mmc_pwrseq_sd8787_driver = {
  76. .probe = mmc_pwrseq_sd8787_probe,
  77. .remove = mmc_pwrseq_sd8787_remove,
  78. .driver = {
  79. .name = "pwrseq_sd8787",
  80. .of_match_table = mmc_pwrseq_sd8787_of_match,
  81. },
  82. };
  83. module_platform_driver(mmc_pwrseq_sd8787_driver);
  84. MODULE_LICENSE("GPL v2");