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 #include <asm/uaccess.h>
  40
  41 /* The LVDS- and panel power controls sits on the
  42  * GPIO port of the ISA bridge.
  43  */
  44
  45 #define CRVML_DEVICE_LPC    0x27B8
  46 #define CRVML_REG_GPIOBAR   0x48
  47 #define CRVML_REG_GPIOEN    0x4C
  48 #define CRVML_GPIOEN_BIT    (1 << 4)
  49 #define CRVML_PANEL_PORT    0x38
  50 #define CRVML_LVDS_ON       0x00000001
  51 #define CRVML_PANEL_ON      0x00000002
  52 #define CRVML_BACKLIGHT_OFF 0x00000004
  53
  54 /* The PLL Clock register sits on Host bridge */
  55 #define CRVML_DEVICE_MCH   0x5001
  56 #define CRVML_REG_MCHBAR   0x44
  57 #define CRVML_REG_MCHEN    0x54
  58 #define CRVML_MCHEN_BIT    (1 << 28)
  59 #define CRVML_MCHMAP_SIZE  4096
  60 #define CRVML_REG_CLOCK    0xc3c
  61 #define CRVML_CLOCK_SHIFT  8
  62 #define CRVML_CLOCK_MASK   0x00000f00
  63
  64 static struct pci_dev *lpc_dev;
  65 static u32 gpio_bar;
  66
  67 struct cr_panel {
  68         struct backlight_device *cr_backlight_device;
  69         struct lcd_device *cr_lcd_device;
  70 };
  71
  72 static int cr_backlight_set_intensity(struct backlight_device *bd)
  73 {
  74         int intensity = bd->props.brightness;
  75         u32 addr = gpio_bar + CRVML_PANEL_PORT;
  76         u32 cur = inl(addr);
  77
  78         if (bd->props.power == FB_BLANK_UNBLANK)
  79                 intensity = FB_BLANK_UNBLANK;
  80         if (bd->props.fb_blank == FB_BLANK_UNBLANK)
  81                 intensity = FB_BLANK_UNBLANK;
  82         if (bd->props.power == FB_BLANK_POWERDOWN)
  83                 intensity = FB_BLANK_POWERDOWN;
  84         if (bd->props.fb_blank == FB_BLANK_POWERDOWN)
  85                 intensity = FB_BLANK_POWERDOWN;
  86
  87         if (intensity == FB_BLANK_UNBLANK) { /* FULL ON */
  88                 cur &= ~CRVML_BACKLIGHT_OFF;
  89                 outl(cur, addr);
  90         } else if (intensity == FB_BLANK_POWERDOWN) { /* OFF */
  91                 cur |= CRVML_BACKLIGHT_OFF;
  92                 outl(cur, addr);
  93         } /* anything else, don't bother */
  94
  95         return 0;
  96 }
  97
  98 static int cr_backlight_get_intensity(struct backlight_device *bd)
  99 {
 100         u32 addr = gpio_bar + CRVML_PANEL_PORT;
 101         u32 cur = inl(addr);
 102         u8 intensity;
 103
 104         if (cur & CRVML_BACKLIGHT_OFF)
 105                 intensity = FB_BLANK_POWERDOWN;
 106         else
 107                 intensity = FB_BLANK_UNBLANK;
 108
 109         return intensity;
 110 }
 111
 112 static struct backlight_ops cr_backlight_ops = {
 113         .get_brightness = cr_backlight_get_intensity,
 114         .update_status = cr_backlight_set_intensity,
 115 };
 116
 117 static void cr_panel_on(void)
 118 {
 119         u32 addr = gpio_bar + CRVML_PANEL_PORT;
 120         u32 cur = inl(addr);
 121
 122         if (!(cur & CRVML_PANEL_ON)) {
 123                 /* Make sure LVDS controller is down. */
 124                 if (cur & 0x00000001) {
 125                         cur &= ~CRVML_LVDS_ON;
 126                         outl(cur, addr);
 127                 }
 128                 /* Power up Panel */
 129                 schedule_timeout(HZ / 10);
 130                 cur |= CRVML_PANEL_ON;
 131                 outl(cur, addr);
 132         }
 133
 134         /* Power up LVDS controller */
 135
 136         if (!(cur & CRVML_LVDS_ON)) {
 137                 schedule_timeout(HZ / 10);
 138                 outl(cur | CRVML_LVDS_ON, addr);
 139         }
 140 }
 141
 142 static void cr_panel_off(void)
 143 {
 144         u32 addr = gpio_bar + CRVML_PANEL_PORT;
 145         u32 cur = inl(addr);
 146
 147         /* Power down LVDS controller first to avoid high currents */
 148         if (cur & CRVML_LVDS_ON) {
 149                 cur &= ~CRVML_LVDS_ON;
 150                 outl(cur, addr);
 151         }
 152         if (cur & CRVML_PANEL_ON) {
 153                 schedule_timeout(HZ / 10);
 154                 outl(cur & ~CRVML_PANEL_ON, addr);
 155         }
 156 }
 157
 158 static int cr_lcd_set_power(struct lcd_device *ld, int power)
 159 {
 160         if (power == FB_BLANK_UNBLANK)
 161                 cr_panel_on();
 162         if (power == FB_BLANK_POWERDOWN)
 163                 cr_panel_off();
 164
 165         return 0;
 166 }
 167
 168 static struct lcd_ops cr_lcd_ops = {
 169         .set_power = cr_lcd_set_power,
 170 };
 171
 172 static int cr_backlight_probe(struct platform_device *pdev)
 173 {
 174         struct cr_panel *crp;
 175         u8 dev_en;
 176
 177         crp = kzalloc(sizeof(*crp), GFP_KERNEL);
 178         if (crp == NULL)
 179                 return -ENOMEM;
 180
 181         lpc_dev = pci_get_device(PCI_VENDOR_ID_INTEL,
 182                                         CRVML_DEVICE_LPC, NULL);
 183         if (!lpc_dev) {
 184                 printk("INTEL CARILLO RANCH LPC not found.\n");
 185                 return -ENODEV;
 186         }
 187
 188         pci_read_config_byte(lpc_dev, CRVML_REG_GPIOEN, &dev_en);
 189         if (!(dev_en & CRVML_GPIOEN_BIT)) {
 190                 printk(KERN_ERR
 191                        "Carillo Ranch GPIO device was not enabled.\n");
 192                 pci_dev_put(lpc_dev);
 193                 return -ENODEV;
 194         }
 195
 196         crp->cr_backlight_device = backlight_device_register("cr-backlight",
 197                                                              &pdev->dev, NULL,
 198                                                              &cr_backlight_ops);
 199         if (IS_ERR(crp->cr_backlight_device)) {
 200                 pci_dev_put(lpc_dev);
 201                 return PTR_ERR(crp->cr_backlight_device);
 202         }
 203
 204         crp->cr_lcd_device = lcd_device_register("cr-lcd",
 205                                                         &pdev->dev,
 206                                                         &cr_lcd_ops);
 207
 208         if (IS_ERR(crp->cr_lcd_device)) {
 209                 pci_dev_put(lpc_dev);
 210                 return PTR_ERR(crp->cr_backlight_device);
 211         }
 212
 213         pci_read_config_dword(lpc_dev, CRVML_REG_GPIOBAR,
 214                               &gpio_bar);
 215         gpio_bar &= ~0x3F;
 216
 217         crp->cr_backlight_device->props.power = FB_BLANK_UNBLANK;
 218         crp->cr_backlight_device->props.brightness = 0;
 219         crp->cr_backlight_device->props.max_brightness = 0;
 220         cr_backlight_set_intensity(crp->cr_backlight_device);
 221
 222         cr_lcd_set_power(crp->cr_lcd_device, FB_BLANK_UNBLANK);
 223
 224         platform_set_drvdata(pdev, crp);
 225
 226         return 0;
 227 }
 228
 229 static int cr_backlight_remove(struct platform_device *pdev)
 230 {
 231         struct cr_panel *crp = platform_get_drvdata(pdev);
 232         crp->cr_backlight_device->props.power = FB_BLANK_POWERDOWN;
 233         crp->cr_backlight_device->props.brightness = 0;
 234         crp->cr_backlight_device->props.max_brightness = 0;
 235         cr_backlight_set_intensity(crp->cr_backlight_device);
 236         cr_lcd_set_power(crp->cr_lcd_device, FB_BLANK_POWERDOWN);
 237         backlight_device_unregister(crp->cr_backlight_device);
 238         lcd_device_unregister(crp->cr_lcd_device);
 239         pci_dev_put(lpc_dev);
 240
 241         return 0;
 242 }
 243
 244 static struct platform_driver cr_backlight_driver = {
 245         .probe = cr_backlight_probe,
 246         .remove = cr_backlight_remove,
 247         .driver = {
 248                    .name = "cr_backlight",
 249                    },
 250 };
 251
 252 static struct platform_device *crp;
 253
 254 static int __init cr_backlight_init(void)
 255 {
 256         int ret = platform_driver_register(&cr_backlight_driver);
 257
 258         if (!ret) {
 259                 crp = platform_device_alloc("cr_backlight", -1);
 260                 if (!crp)
 261                         return -ENOMEM;
 262
 263                 ret = platform_device_add(crp);
 264
 265                 if (ret) {
 266                         platform_device_put(crp);
 267                         platform_driver_unregister(&cr_backlight_driver);
 268                 }
 269         }
 270
 271         printk("Carillo Ranch Backlight Driver Initialized.\n");
 272
 273         return ret;
 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");