dev-backlight-s3c64xx.c 4.1 KB

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  1. // SPDX-License-Identifier: GPL-2.0
  2. //
  3. // Copyright (c) 2011 Samsung Electronics Co., Ltd.
  4. // http://www.samsung.com
  5. //
  6. // Common infrastructure for PWM Backlight for Samsung boards
  7. #include <linux/gpio.h>
  8. #include <linux/platform_device.h>
  9. #include <linux/slab.h>
  10. #include <linux/io.h>
  11. #include <linux/pwm_backlight.h>
  12. #include "devs.h"
  13. #include "gpio-cfg.h"
  14. #include "backlight-s3c64xx.h"
  15. struct samsung_bl_drvdata {
  16. struct platform_pwm_backlight_data plat_data;
  17. struct samsung_bl_gpio_info *gpio_info;
  18. };
  19. static int samsung_bl_init(struct device *dev)
  20. {
  21. int ret = 0;
  22. struct platform_pwm_backlight_data *pdata = dev->platform_data;
  23. struct samsung_bl_drvdata *drvdata = container_of(pdata,
  24. struct samsung_bl_drvdata, plat_data);
  25. struct samsung_bl_gpio_info *bl_gpio_info = drvdata->gpio_info;
  26. ret = gpio_request(bl_gpio_info->no, "Backlight");
  27. if (ret) {
  28. printk(KERN_ERR "failed to request GPIO for LCD Backlight\n");
  29. return ret;
  30. }
  31. /* Configure GPIO pin with specific GPIO function for PWM timer */
  32. s3c_gpio_cfgpin(bl_gpio_info->no, bl_gpio_info->func);
  33. return 0;
  34. }
  35. static void samsung_bl_exit(struct device *dev)
  36. {
  37. struct platform_pwm_backlight_data *pdata = dev->platform_data;
  38. struct samsung_bl_drvdata *drvdata = container_of(pdata,
  39. struct samsung_bl_drvdata, plat_data);
  40. struct samsung_bl_gpio_info *bl_gpio_info = drvdata->gpio_info;
  41. s3c_gpio_cfgpin(bl_gpio_info->no, S3C_GPIO_OUTPUT);
  42. gpio_free(bl_gpio_info->no);
  43. }
  44. /* Initialize few important fields of platform_pwm_backlight_data
  45. * structure with default values. These fields can be overridden by
  46. * board-specific values sent from machine file.
  47. * For ease of operation, these fields are initialized with values
  48. * used by most samsung boards.
  49. * Users has the option of sending info about other parameters
  50. * for their specific boards
  51. */
  52. static struct samsung_bl_drvdata samsung_dfl_bl_data __initdata = {
  53. .plat_data = {
  54. .max_brightness = 255,
  55. .dft_brightness = 255,
  56. .init = samsung_bl_init,
  57. .exit = samsung_bl_exit,
  58. },
  59. };
  60. static struct platform_device samsung_dfl_bl_device __initdata = {
  61. .name = "pwm-backlight",
  62. };
  63. /* samsung_bl_set - Set board specific data (if any) provided by user for
  64. * PWM Backlight control and register specific PWM and backlight device.
  65. * @gpio_info: structure containing GPIO info for PWM timer
  66. * @bl_data: structure containing Backlight control data
  67. */
  68. void __init samsung_bl_set(struct samsung_bl_gpio_info *gpio_info,
  69. struct platform_pwm_backlight_data *bl_data)
  70. {
  71. int ret = 0;
  72. struct platform_device *samsung_bl_device;
  73. struct samsung_bl_drvdata *samsung_bl_drvdata;
  74. struct platform_pwm_backlight_data *samsung_bl_data;
  75. samsung_bl_device = kmemdup(&samsung_dfl_bl_device,
  76. sizeof(struct platform_device), GFP_KERNEL);
  77. if (!samsung_bl_device)
  78. return;
  79. samsung_bl_drvdata = kmemdup(&samsung_dfl_bl_data,
  80. sizeof(samsung_dfl_bl_data), GFP_KERNEL);
  81. if (!samsung_bl_drvdata)
  82. goto err_data;
  83. samsung_bl_device->dev.platform_data = &samsung_bl_drvdata->plat_data;
  84. samsung_bl_drvdata->gpio_info = gpio_info;
  85. samsung_bl_data = &samsung_bl_drvdata->plat_data;
  86. /* Copy board specific data provided by user */
  87. samsung_bl_device->dev.parent = &samsung_device_pwm.dev;
  88. if (bl_data->max_brightness)
  89. samsung_bl_data->max_brightness = bl_data->max_brightness;
  90. if (bl_data->dft_brightness)
  91. samsung_bl_data->dft_brightness = bl_data->dft_brightness;
  92. if (bl_data->lth_brightness)
  93. samsung_bl_data->lth_brightness = bl_data->lth_brightness;
  94. if (bl_data->init)
  95. samsung_bl_data->init = bl_data->init;
  96. if (bl_data->notify)
  97. samsung_bl_data->notify = bl_data->notify;
  98. if (bl_data->notify_after)
  99. samsung_bl_data->notify_after = bl_data->notify_after;
  100. if (bl_data->exit)
  101. samsung_bl_data->exit = bl_data->exit;
  102. if (bl_data->check_fb)
  103. samsung_bl_data->check_fb = bl_data->check_fb;
  104. /* Register the Backlight dev */
  105. ret = platform_device_register(samsung_bl_device);
  106. if (ret) {
  107. printk(KERN_ERR "failed to register backlight device: %d\n", ret);
  108. goto err_plat_reg2;
  109. }
  110. return;
  111. err_plat_reg2:
  112. kfree(samsung_bl_data);
  113. err_data:
  114. kfree(samsung_bl_device);
  115. }