omap1_bl.c 3.9 KB

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  1. // SPDX-License-Identifier: GPL-2.0-or-later
  2. /*
  3. * Backlight driver for OMAP based boards.
  4. *
  5. * Copyright (c) 2006 Andrzej Zaborowski <balrog@zabor.org>
  6. */
  7. #include <linux/module.h>
  8. #include <linux/kernel.h>
  9. #include <linux/init.h>
  10. #include <linux/platform_device.h>
  11. #include <linux/fb.h>
  12. #include <linux/backlight.h>
  13. #include <linux/slab.h>
  14. #include <linux/platform_data/omap1_bl.h>
  15. #include <mach/hardware.h>
  16. #include <mach/mux.h>
  17. #define OMAPBL_MAX_INTENSITY 0xff
  18. struct omap_backlight {
  19. int powermode;
  20. int current_intensity;
  21. struct device *dev;
  22. struct omap_backlight_config *pdata;
  23. };
  24. static inline void omapbl_send_intensity(int intensity)
  25. {
  26. omap_writeb(intensity, OMAP_PWL_ENABLE);
  27. }
  28. static inline void omapbl_send_enable(int enable)
  29. {
  30. omap_writeb(enable, OMAP_PWL_CLK_ENABLE);
  31. }
  32. static void omapbl_blank(struct omap_backlight *bl, int mode)
  33. {
  34. if (bl->pdata->set_power)
  35. bl->pdata->set_power(bl->dev, mode);
  36. switch (mode) {
  37. case FB_BLANK_NORMAL:
  38. case FB_BLANK_VSYNC_SUSPEND:
  39. case FB_BLANK_HSYNC_SUSPEND:
  40. case FB_BLANK_POWERDOWN:
  41. omapbl_send_intensity(0);
  42. omapbl_send_enable(0);
  43. break;
  44. case FB_BLANK_UNBLANK:
  45. omapbl_send_intensity(bl->current_intensity);
  46. omapbl_send_enable(1);
  47. break;
  48. }
  49. }
  50. #ifdef CONFIG_PM_SLEEP
  51. static int omapbl_suspend(struct device *dev)
  52. {
  53. struct backlight_device *bl_dev = dev_get_drvdata(dev);
  54. struct omap_backlight *bl = bl_get_data(bl_dev);
  55. omapbl_blank(bl, FB_BLANK_POWERDOWN);
  56. return 0;
  57. }
  58. static int omapbl_resume(struct device *dev)
  59. {
  60. struct backlight_device *bl_dev = dev_get_drvdata(dev);
  61. struct omap_backlight *bl = bl_get_data(bl_dev);
  62. omapbl_blank(bl, bl->powermode);
  63. return 0;
  64. }
  65. #endif
  66. static int omapbl_set_power(struct backlight_device *dev, int state)
  67. {
  68. struct omap_backlight *bl = bl_get_data(dev);
  69. omapbl_blank(bl, state);
  70. bl->powermode = state;
  71. return 0;
  72. }
  73. static int omapbl_update_status(struct backlight_device *dev)
  74. {
  75. struct omap_backlight *bl = bl_get_data(dev);
  76. if (bl->current_intensity != dev->props.brightness) {
  77. if (bl->powermode == FB_BLANK_UNBLANK)
  78. omapbl_send_intensity(dev->props.brightness);
  79. bl->current_intensity = dev->props.brightness;
  80. }
  81. if (dev->props.fb_blank != bl->powermode)
  82. omapbl_set_power(dev, dev->props.fb_blank);
  83. return 0;
  84. }
  85. static int omapbl_get_intensity(struct backlight_device *dev)
  86. {
  87. struct omap_backlight *bl = bl_get_data(dev);
  88. return bl->current_intensity;
  89. }
  90. static const struct backlight_ops omapbl_ops = {
  91. .get_brightness = omapbl_get_intensity,
  92. .update_status = omapbl_update_status,
  93. };
  94. static int omapbl_probe(struct platform_device *pdev)
  95. {
  96. struct backlight_properties props;
  97. struct backlight_device *dev;
  98. struct omap_backlight *bl;
  99. struct omap_backlight_config *pdata = dev_get_platdata(&pdev->dev);
  100. if (!pdata)
  101. return -ENXIO;
  102. bl = devm_kzalloc(&pdev->dev, sizeof(struct omap_backlight),
  103. GFP_KERNEL);
  104. if (unlikely(!bl))
  105. return -ENOMEM;
  106. memset(&props, 0, sizeof(struct backlight_properties));
  107. props.type = BACKLIGHT_RAW;
  108. props.max_brightness = OMAPBL_MAX_INTENSITY;
  109. dev = devm_backlight_device_register(&pdev->dev, "omap-bl", &pdev->dev,
  110. bl, &omapbl_ops, &props);
  111. if (IS_ERR(dev))
  112. return PTR_ERR(dev);
  113. bl->powermode = FB_BLANK_POWERDOWN;
  114. bl->current_intensity = 0;
  115. bl->pdata = pdata;
  116. bl->dev = &pdev->dev;
  117. platform_set_drvdata(pdev, dev);
  118. omap_cfg_reg(PWL); /* Conflicts with UART3 */
  119. dev->props.fb_blank = FB_BLANK_UNBLANK;
  120. dev->props.brightness = pdata->default_intensity;
  121. omapbl_update_status(dev);
  122. dev_info(&pdev->dev, "OMAP LCD backlight initialised\n");
  123. return 0;
  124. }
  125. static SIMPLE_DEV_PM_OPS(omapbl_pm_ops, omapbl_suspend, omapbl_resume);
  126. static struct platform_driver omapbl_driver = {
  127. .probe = omapbl_probe,
  128. .driver = {
  129. .name = "omap-bl",
  130. .pm = &omapbl_pm_ops,
  131. },
  132. };
  133. module_platform_driver(omapbl_driver);
  134. MODULE_AUTHOR("Andrzej Zaborowski <balrog@zabor.org>");
  135. MODULE_DESCRIPTION("OMAP LCD Backlight driver");
  136. MODULE_LICENSE("GPL");