1 /* 2 * Backlight driver for OMAP based boards. 3 * 4 * Copyright (c) 2006 Andrzej Zaborowski <balrog@zabor.org> 5 * 6 * This package is free software; you can redistribute it and/or modify 7 * it under the terms of the GNU General Public License as published by 8 * the Free Software Foundation; either version 2 of the License, or 9 * (at your option) any later version. 10 * 11 * This package is distributed in the hope that it will be useful, 12 * but WITHOUT ANY WARRANTY; without even the implied warranty of 13 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the 14 * GNU General Public License for more details. 15 * 16 * You should have received a copy of the GNU General Public License 17 * along with this package; if not, write to the Free Software 18 * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA 19 */ 20 21 #include <linux/module.h> 22 #include <linux/kernel.h> 23 #include <linux/init.h> 24 #include <linux/platform_device.h> 25 #include <linux/fb.h> 26 #include <linux/backlight.h> 27 #include <linux/slab.h> 28 #include <linux/platform_data/omap1_bl.h> 29 30 #include <mach/hardware.h> 31 #include <mach/mux.h> 32 33 #define OMAPBL_MAX_INTENSITY 0xff 34 35 struct omap_backlight { 36 int powermode; 37 int current_intensity; 38 39 struct device *dev; 40 struct omap_backlight_config *pdata; 41 }; 42 43 static inline void omapbl_send_intensity(int intensity) 44 { 45 omap_writeb(intensity, OMAP_PWL_ENABLE); 46 } 47 48 static inline void omapbl_send_enable(int enable) 49 { 50 omap_writeb(enable, OMAP_PWL_CLK_ENABLE); 51 } 52 53 static void omapbl_blank(struct omap_backlight *bl, int mode) 54 { 55 if (bl->pdata->set_power) 56 bl->pdata->set_power(bl->dev, mode); 57 58 switch (mode) { 59 case FB_BLANK_NORMAL: 60 case FB_BLANK_VSYNC_SUSPEND: 61 case FB_BLANK_HSYNC_SUSPEND: 62 case FB_BLANK_POWERDOWN: 63 omapbl_send_intensity(0); 64 omapbl_send_enable(0); 65 break; 66 67 case FB_BLANK_UNBLANK: 68 omapbl_send_intensity(bl->current_intensity); 69 omapbl_send_enable(1); 70 break; 71 } 72 } 73 74 #ifdef CONFIG_PM_SLEEP 75 static int omapbl_suspend(struct device *dev) 76 { 77 struct backlight_device *bl_dev = dev_get_drvdata(dev); 78 struct omap_backlight *bl = bl_get_data(bl_dev); 79 80 omapbl_blank(bl, FB_BLANK_POWERDOWN); 81 return 0; 82 } 83 84 static int omapbl_resume(struct device *dev) 85 { 86 struct backlight_device *bl_dev = dev_get_drvdata(dev); 87 struct omap_backlight *bl = bl_get_data(bl_dev); 88 89 omapbl_blank(bl, bl->powermode); 90 return 0; 91 } 92 #endif 93 94 static int omapbl_set_power(struct backlight_device *dev, int state) 95 { 96 struct omap_backlight *bl = bl_get_data(dev); 97 98 omapbl_blank(bl, state); 99 bl->powermode = state; 100 101 return 0; 102 } 103 104 static int omapbl_update_status(struct backlight_device *dev) 105 { 106 struct omap_backlight *bl = bl_get_data(dev); 107 108 if (bl->current_intensity != dev->props.brightness) { 109 if (bl->powermode == FB_BLANK_UNBLANK) 110 omapbl_send_intensity(dev->props.brightness); 111 bl->current_intensity = dev->props.brightness; 112 } 113 114 if (dev->props.fb_blank != bl->powermode) 115 omapbl_set_power(dev, dev->props.fb_blank); 116 117 return 0; 118 } 119 120 static int omapbl_get_intensity(struct backlight_device *dev) 121 { 122 struct omap_backlight *bl = bl_get_data(dev); 123 124 return bl->current_intensity; 125 } 126 127 static const struct backlight_ops omapbl_ops = { 128 .get_brightness = omapbl_get_intensity, 129 .update_status = omapbl_update_status, 130 }; 131 132 static int omapbl_probe(struct platform_device *pdev) 133 { 134 struct backlight_properties props; 135 struct backlight_device *dev; 136 struct omap_backlight *bl; 137 struct omap_backlight_config *pdata = dev_get_platdata(&pdev->dev); 138 139 if (!pdata) 140 return -ENXIO; 141 142 bl = devm_kzalloc(&pdev->dev, sizeof(struct omap_backlight), 143 GFP_KERNEL); 144 if (unlikely(!bl)) 145 return -ENOMEM; 146 147 memset(&props, 0, sizeof(struct backlight_properties)); 148 props.type = BACKLIGHT_RAW; 149 props.max_brightness = OMAPBL_MAX_INTENSITY; 150 dev = devm_backlight_device_register(&pdev->dev, "omap-bl", &pdev->dev, 151 bl, &omapbl_ops, &props); 152 if (IS_ERR(dev)) 153 return PTR_ERR(dev); 154 155 bl->powermode = FB_BLANK_POWERDOWN; 156 bl->current_intensity = 0; 157 158 bl->pdata = pdata; 159 bl->dev = &pdev->dev; 160 161 platform_set_drvdata(pdev, dev); 162 163 omap_cfg_reg(PWL); /* Conflicts with UART3 */ 164 165 dev->props.fb_blank = FB_BLANK_UNBLANK; 166 dev->props.brightness = pdata->default_intensity; 167 omapbl_update_status(dev); 168 169 dev_info(&pdev->dev, "OMAP LCD backlight initialised\n"); 170 171 return 0; 172 } 173 174 static SIMPLE_DEV_PM_OPS(omapbl_pm_ops, omapbl_suspend, omapbl_resume); 175 176 static struct platform_driver omapbl_driver = { 177 .probe = omapbl_probe, 178 .driver = { 179 .name = "omap-bl", 180 .pm = &omapbl_pm_ops, 181 }, 182 }; 183 184 module_platform_driver(omapbl_driver); 185 186 MODULE_AUTHOR("Andrzej Zaborowski <balrog@zabor.org>"); 187 MODULE_DESCRIPTION("OMAP LCD Backlight driver"); 188 MODULE_LICENSE("GPL"); 189