drivers/video/backlight/cr_bllcd.c

   1 /*
   2  * Copyright (c) Intel Corp. 2007.
   3  * All Rights Reserved.
   4  *
   5  * Intel funded Tungsten Graphics (http://www.tungstengraphics.com) to
   6  * develop this driver.
   7  *
   8  * This file is part of the Carillo Ranch video subsystem driver.
   9  * The Carillo Ranch video subsystem driver is free software;
  10  * you can redistribute it and/or modify
  11  * it under the terms of the GNU General Public License as published by
  12  * the Free Software Foundation; either version 2 of the License, or
  13  * (at your option) any later version.
  14  *
  15  * The Carillo Ranch video subsystem driver is distributed
  16  * in the hope that it will be useful,
  17  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  18  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  19  * GNU General Public License for more details.
  20  *
  21  * You should have received a copy of the GNU General Public License
  22  * along with this driver; if not, write to the Free Software
  23  * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA
  24  *
  25  * Authors:
  26  *   Thomas Hellstrom <thomas-at-tungstengraphics-dot-com>
  27  *   Alan Hourihane <alanh-at-tungstengraphics-dot-com>
  28  */
  29
  30 #include <linux/module.h>
  31 #include <linux/kernel.h>
  32 #include <linux/init.h>
  33 #include <linux/platform_device.h>
  34 #include <linux/mutex.h>
  35 #include <linux/fb.h>
  36 #include <linux/backlight.h>
  37 #include <linux/lcd.h>
  38 #include <linux/pci.h>
  39
  40 /* The LVDS- and panel power controls sits on the
  41  * GPIO port of the ISA bridge.
  42  */
  43
  44 #define CRVML_DEVICE_LPC    0x27B8
  45 #define CRVML_REG_GPIOBAR   0x48
  46 #define CRVML_REG_GPIOEN    0x4C
  47 #define CRVML_GPIOEN_BIT    (1 << 4)
  48 #define CRVML_PANEL_PORT    0x38
  49 #define CRVML_LVDS_ON       0x00000001
  50 #define CRVML_PANEL_ON      0x00000002
  51 #define CRVML_BACKLIGHT_OFF 0x00000004
  52
  53 /* The PLL Clock register sits on Host bridge */
  54 #define CRVML_DEVICE_MCH   0x5001
  55 #define CRVML_REG_MCHBAR   0x44
  56 #define CRVML_REG_MCHEN    0x54
  57 #define CRVML_MCHEN_BIT    (1 << 28)
  58 #define CRVML_MCHMAP_SIZE  4096
  59 #define CRVML_REG_CLOCK    0xc3c
  60 #define CRVML_CLOCK_SHIFT  8
  61 #define CRVML_CLOCK_MASK   0x00000f00
  62
  63 static struct pci_dev *lpc_dev;
  64 static u32 gpio_bar;
  65
  66 struct cr_panel {
  67         struct backlight_device *cr_backlight_device;
  68         struct lcd_device *cr_lcd_device;
  69 };
  70
  71 static int cr_backlight_set_intensity(struct backlight_device *bd)
  72 {
  73         int intensity = bd->props.brightness;
  74         u32 addr = gpio_bar + CRVML_PANEL_PORT;
  75         u32 cur = inl(addr);
  76
  77         if (bd->props.power == FB_BLANK_UNBLANK)
  78                 intensity = FB_BLANK_UNBLANK;
  79         if (bd->props.fb_blank == FB_BLANK_UNBLANK)
  80                 intensity = FB_BLANK_UNBLANK;
  81         if (bd->props.power == FB_BLANK_POWERDOWN)
  82                 intensity = FB_BLANK_POWERDOWN;
  83         if (bd->props.fb_blank == FB_BLANK_POWERDOWN)
  84                 intensity = FB_BLANK_POWERDOWN;
  85
  86         if (intensity == FB_BLANK_UNBLANK) { /* FULL ON */
  87                 cur &= ~CRVML_BACKLIGHT_OFF;
  88                 outl(cur, addr);
  89         } else if (intensity == FB_BLANK_POWERDOWN) { /* OFF */
  90                 cur |= CRVML_BACKLIGHT_OFF;
  91                 outl(cur, addr);
  92         } /* anything else, don't bother */
  93
  94         return 0;
  95 }
  96
  97 static int cr_backlight_get_intensity(struct backlight_device *bd)
  98 {
  99         u32 addr = gpio_bar + CRVML_PANEL_PORT;
 100         u32 cur = inl(addr);
 101         u8 intensity;
 102
 103         if (cur & CRVML_BACKLIGHT_OFF)
 104                 intensity = FB_BLANK_POWERDOWN;
 105         else
 106                 intensity = FB_BLANK_UNBLANK;
 107
 108         return intensity;
 109 }
 110
 111 static const struct backlight_ops cr_backlight_ops = {
 112         .get_brightness = cr_backlight_get_intensity,
 113         .update_status = cr_backlight_set_intensity,
 114 };
 115
 116 static void cr_panel_on(void)
 117 {
 118         u32 addr = gpio_bar + CRVML_PANEL_PORT;
 119         u32 cur = inl(addr);
 120
 121         if (!(cur & CRVML_PANEL_ON)) {
 122                 /* Make sure LVDS controller is down. */
 123                 if (cur & 0x00000001) {
 124                         cur &= ~CRVML_LVDS_ON;
 125                         outl(cur, addr);
 126                 }
 127                 /* Power up Panel */
 128                 schedule_timeout(HZ / 10);
 129                 cur |= CRVML_PANEL_ON;
 130                 outl(cur, addr);
 131         }
 132
 133         /* Power up LVDS controller */
 134
 135         if (!(cur & CRVML_LVDS_ON)) {
 136                 schedule_timeout(HZ / 10);
 137                 outl(cur | CRVML_LVDS_ON, addr);
 138         }
 139 }
 140
 141 static void cr_panel_off(void)
 142 {
 143         u32 addr = gpio_bar + CRVML_PANEL_PORT;
 144         u32 cur = inl(addr);
 145
 146         /* Power down LVDS controller first to avoid high currents */
 147         if (cur & CRVML_LVDS_ON) {
 148                 cur &= ~CRVML_LVDS_ON;
 149                 outl(cur, addr);
 150         }
 151         if (cur & CRVML_PANEL_ON) {
 152                 schedule_timeout(HZ / 10);
 153                 outl(cur & ~CRVML_PANEL_ON, addr);
 154         }
 155 }
 156
 157 static int cr_lcd_set_power(struct lcd_device *ld, int power)
 158 {
 159         if (power == FB_BLANK_UNBLANK)
 160                 cr_panel_on();
 161         if (power == FB_BLANK_POWERDOWN)
 162                 cr_panel_off();
 163
 164         return 0;
 165 }
 166
 167 static struct lcd_ops cr_lcd_ops = {
 168         .set_power = cr_lcd_set_power,
 169 };
 170
 171 static int cr_backlight_probe(struct platform_device *pdev)
 172 {
 173         struct backlight_device *bdp;
 174         struct lcd_device *ldp;
 175         struct cr_panel *crp;
 176         u8 dev_en;
 177
 178         lpc_dev = pci_get_device(PCI_VENDOR_ID_INTEL,
 179                                         CRVML_DEVICE_LPC, NULL);
 180         if (!lpc_dev) {
 181                 printk("INTEL CARILLO RANCH LPC not found.\n");
 182                 return -ENODEV;
 183         }
 184
 185         pci_read_config_byte(lpc_dev, CRVML_REG_GPIOEN, &dev_en);
 186         if (!(dev_en & CRVML_GPIOEN_BIT)) {
 187                 printk(KERN_ERR
 188                        "Carillo Ranch GPIO device was not enabled.\n");
 189                 pci_dev_put(lpc_dev);
 190                 return -ENODEV;
 191         }
 192
 193         bdp = backlight_device_register("cr-backlight",
 194                                         &pdev->dev, NULL, &cr_backlight_ops);
 195         if (IS_ERR(bdp)) {
 196                 pci_dev_put(lpc_dev);
 197                 return PTR_ERR(bdp);
 198         }
 199
 200         ldp = lcd_device_register("cr-lcd", &pdev->dev, NULL, &cr_lcd_ops);
 201         if (IS_ERR(ldp)) {
 202                 backlight_device_unregister(bdp);
 203                 pci_dev_put(lpc_dev);
 204                 return PTR_ERR(ldp);
 205         }
 206
 207         pci_read_config_dword(lpc_dev, CRVML_REG_GPIOBAR,
 208                               &gpio_bar);
 209         gpio_bar &= ~0x3F;
 210
 211         crp = kzalloc(sizeof(*crp), GFP_KERNEL);
 212         if (!crp) {
 213                 lcd_device_unregister(ldp);
 214                 backlight_device_unregister(bdp);
 215                 pci_dev_put(lpc_dev);
 216                 return -ENOMEM;
 217         }
 218
 219         crp->cr_backlight_device = bdp;
 220         crp->cr_lcd_device = ldp;
 221         crp->cr_backlight_device->props.power = FB_BLANK_UNBLANK;
 222         crp->cr_backlight_device->props.brightness = 0;
 223         crp->cr_backlight_device->props.max_brightness = 0;
 224         cr_backlight_set_intensity(crp->cr_backlight_device);
 225
 226         cr_lcd_set_power(crp->cr_lcd_device, FB_BLANK_UNBLANK);
 227
 228         platform_set_drvdata(pdev, crp);
 229
 230         return 0;
 231 }
 232
 233 static int cr_backlight_remove(struct platform_device *pdev)
 234 {
 235         struct cr_panel *crp = platform_get_drvdata(pdev);
 236         crp->cr_backlight_device->props.power = FB_BLANK_POWERDOWN;
 237         crp->cr_backlight_device->props.brightness = 0;
 238         crp->cr_backlight_device->props.max_brightness = 0;
 239         cr_backlight_set_intensity(crp->cr_backlight_device);
 240         cr_lcd_set_power(crp->cr_lcd_device, FB_BLANK_POWERDOWN);
 241         backlight_device_unregister(crp->cr_backlight_device);
 242         lcd_device_unregister(crp->cr_lcd_device);
 243         pci_dev_put(lpc_dev);
 244
 245         return 0;
 246 }
 247
 248 static struct platform_driver cr_backlight_driver = {
 249         .probe = cr_backlight_probe,
 250         .remove = cr_backlight_remove,
 251         .driver = {
 252                    .name = "cr_backlight",
 253                    },
 254 };
 255
 256 static struct platform_device *crp;
 257
 258 static int __init cr_backlight_init(void)
 259 {
 260         int ret = platform_driver_register(&cr_backlight_driver);
 261
 262         if (ret)
 263                 return ret;
 264
 265         crp = platform_device_register_simple("cr_backlight", -1, NULL, 0);
 266         if (IS_ERR(crp)) {
 267                 platform_driver_unregister(&cr_backlight_driver);
 268                 return PTR_ERR(crp);
 269         }
 270
 271         printk("Carillo Ranch Backlight Driver Initialized.\n");
 272
 273         return 0;
 274 }
 275
 276 static void __exit cr_backlight_exit(void)
 277 {
 278         platform_device_unregister(crp);
 279         platform_driver_unregister(&cr_backlight_driver);
 280 }
 281
 282 module_init(cr_backlight_init);
 283 module_exit(cr_backlight_exit);
 284
 285 MODULE_AUTHOR("Tungsten Graphics Inc.");
 286 MODULE_DESCRIPTION("Carillo Ranch Backlight Driver");
 287 MODULE_LICENSE("GPL");