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 #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
  31
  32 #include <linux/module.h>
  33 #include <linux/kernel.h>
  34 #include <linux/init.h>
  35 #include <linux/platform_device.h>
  36 #include <linux/mutex.h>
  37 #include <linux/fb.h>
  38 #include <linux/backlight.h>
  39 #include <linux/lcd.h>
  40 #include <linux/pci.h>
  41 #include <linux/slab.h>
  42
  43 /* The LVDS- and panel power controls sits on the
  44  * GPIO port of the ISA bridge.
  45  */
  46
  47 #define CRVML_DEVICE_LPC    0x27B8
  48 #define CRVML_REG_GPIOBAR   0x48
  49 #define CRVML_REG_GPIOEN    0x4C
  50 #define CRVML_GPIOEN_BIT    (1 << 4)
  51 #define CRVML_PANEL_PORT    0x38
  52 #define CRVML_LVDS_ON       0x00000001
  53 #define CRVML_PANEL_ON      0x00000002
  54 #define CRVML_BACKLIGHT_OFF 0x00000004
  55
  56 /* The PLL Clock register sits on Host bridge */
  57 #define CRVML_DEVICE_MCH   0x5001
  58 #define CRVML_REG_MCHBAR   0x44
  59 #define CRVML_REG_MCHEN    0x54
  60 #define CRVML_MCHEN_BIT    (1 << 28)
  61 #define CRVML_MCHMAP_SIZE  4096
  62 #define CRVML_REG_CLOCK    0xc3c
  63 #define CRVML_CLOCK_SHIFT  8
  64 #define CRVML_CLOCK_MASK   0x00000f00
  65
  66 static struct pci_dev *lpc_dev;
  67 static u32 gpio_bar;
  68
  69 struct cr_panel {
  70         struct backlight_device *cr_backlight_device;
  71         struct lcd_device *cr_lcd_device;
  72 };
  73
  74 static int cr_backlight_set_intensity(struct backlight_device *bd)
  75 {
  76         int intensity = bd->props.brightness;
  77         u32 addr = gpio_bar + CRVML_PANEL_PORT;
  78         u32 cur = inl(addr);
  79
  80         if (bd->props.power == FB_BLANK_UNBLANK)
  81                 intensity = FB_BLANK_UNBLANK;
  82         if (bd->props.fb_blank == FB_BLANK_UNBLANK)
  83                 intensity = FB_BLANK_UNBLANK;
  84         if (bd->props.power == FB_BLANK_POWERDOWN)
  85                 intensity = FB_BLANK_POWERDOWN;
  86         if (bd->props.fb_blank == FB_BLANK_POWERDOWN)
  87                 intensity = FB_BLANK_POWERDOWN;
  88
  89         if (intensity == FB_BLANK_UNBLANK) { /* FULL ON */
  90                 cur &= ~CRVML_BACKLIGHT_OFF;
  91                 outl(cur, addr);
  92         } else if (intensity == FB_BLANK_POWERDOWN) { /* OFF */
  93                 cur |= CRVML_BACKLIGHT_OFF;
  94                 outl(cur, addr);
  95         } /* anything else, don't bother */
  96
  97         return 0;
  98 }
  99
 100 static int cr_backlight_get_intensity(struct backlight_device *bd)
 101 {
 102         u32 addr = gpio_bar + CRVML_PANEL_PORT;
 103         u32 cur = inl(addr);
 104         u8 intensity;
 105
 106         if (cur & CRVML_BACKLIGHT_OFF)
 107                 intensity = FB_BLANK_POWERDOWN;
 108         else
 109                 intensity = FB_BLANK_UNBLANK;
 110
 111         return intensity;
 112 }
 113
 114 static const struct backlight_ops cr_backlight_ops = {
 115         .get_brightness = cr_backlight_get_intensity,
 116         .update_status = cr_backlight_set_intensity,
 117 };
 118
 119 static void cr_panel_on(void)
 120 {
 121         u32 addr = gpio_bar + CRVML_PANEL_PORT;
 122         u32 cur = inl(addr);
 123
 124         if (!(cur & CRVML_PANEL_ON)) {
 125                 /* Make sure LVDS controller is down. */
 126                 if (cur & 0x00000001) {
 127                         cur &= ~CRVML_LVDS_ON;
 128                         outl(cur, addr);
 129                 }
 130                 /* Power up Panel */
 131                 schedule_timeout(HZ / 10);
 132                 cur |= CRVML_PANEL_ON;
 133                 outl(cur, addr);
 134         }
 135
 136         /* Power up LVDS controller */
 137
 138         if (!(cur & CRVML_LVDS_ON)) {
 139                 schedule_timeout(HZ / 10);
 140                 outl(cur | CRVML_LVDS_ON, addr);
 141         }
 142 }
 143
 144 static void cr_panel_off(void)
 145 {
 146         u32 addr = gpio_bar + CRVML_PANEL_PORT;
 147         u32 cur = inl(addr);
 148
 149         /* Power down LVDS controller first to avoid high currents */
 150         if (cur & CRVML_LVDS_ON) {
 151                 cur &= ~CRVML_LVDS_ON;
 152                 outl(cur, addr);
 153         }
 154         if (cur & CRVML_PANEL_ON) {
 155                 schedule_timeout(HZ / 10);
 156                 outl(cur & ~CRVML_PANEL_ON, addr);
 157         }
 158 }
 159
 160 static int cr_lcd_set_power(struct lcd_device *ld, int power)
 161 {
 162         if (power == FB_BLANK_UNBLANK)
 163                 cr_panel_on();
 164         if (power == FB_BLANK_POWERDOWN)
 165                 cr_panel_off();
 166
 167         return 0;
 168 }
 169
 170 static struct lcd_ops cr_lcd_ops = {
 171         .set_power = cr_lcd_set_power,
 172 };
 173
 174 static int cr_backlight_probe(struct platform_device *pdev)
 175 {
 176         struct backlight_properties props;
 177         struct backlight_device *bdp;
 178         struct lcd_device *ldp;
 179         struct cr_panel *crp;
 180         u8 dev_en;
 181
 182         lpc_dev = pci_get_device(PCI_VENDOR_ID_INTEL,
 183                                         CRVML_DEVICE_LPC, NULL);
 184         if (!lpc_dev) {
 185                 pr_err("INTEL CARILLO RANCH LPC not found.\n");
 186                 return -ENODEV;
 187         }
 188
 189         pci_read_config_byte(lpc_dev, CRVML_REG_GPIOEN, &dev_en);
 190         if (!(dev_en & CRVML_GPIOEN_BIT)) {
 191                 pr_err("Carillo Ranch GPIO device was not enabled.\n");
 192                 pci_dev_put(lpc_dev);
 193                 return -ENODEV;
 194         }
 195
 196         memset(&props, 0, sizeof(struct backlight_properties));
 197         props.type = BACKLIGHT_RAW;
 198         bdp = devm_backlight_device_register(&pdev->dev, "cr-backlight",
 199                                         &pdev->dev, NULL, &cr_backlight_ops,
 200                                         &props);
 201         if (IS_ERR(bdp)) {
 202                 pci_dev_put(lpc_dev);
 203                 return PTR_ERR(bdp);
 204         }
 205
 206         ldp = devm_lcd_device_register(&pdev->dev, "cr-lcd", &pdev->dev, NULL,
 207                                         &cr_lcd_ops);
 208         if (IS_ERR(ldp)) {
 209                 pci_dev_put(lpc_dev);
 210                 return PTR_ERR(ldp);
 211         }
 212
 213         pci_read_config_dword(lpc_dev, CRVML_REG_GPIOBAR,
 214                               &gpio_bar);
 215         gpio_bar &= ~0x3F;
 216
 217         crp = devm_kzalloc(&pdev->dev, sizeof(*crp), GFP_KERNEL);
 218         if (!crp) {
 219                 pci_dev_put(lpc_dev);
 220                 return -ENOMEM;
 221         }
 222
 223         crp->cr_backlight_device = bdp;
 224         crp->cr_lcd_device = ldp;
 225         crp->cr_backlight_device->props.power = FB_BLANK_UNBLANK;
 226         crp->cr_backlight_device->props.brightness = 0;
 227         cr_backlight_set_intensity(crp->cr_backlight_device);
 228         cr_lcd_set_power(crp->cr_lcd_device, FB_BLANK_UNBLANK);
 229
 230         platform_set_drvdata(pdev, crp);
 231
 232         return 0;
 233 }
 234
 235 static int cr_backlight_remove(struct platform_device *pdev)
 236 {
 237         struct cr_panel *crp = platform_get_drvdata(pdev);
 238
 239         crp->cr_backlight_device->props.power = FB_BLANK_POWERDOWN;
 240         crp->cr_backlight_device->props.brightness = 0;
 241         crp->cr_backlight_device->props.max_brightness = 0;
 242         cr_backlight_set_intensity(crp->cr_backlight_device);
 243         cr_lcd_set_power(crp->cr_lcd_device, FB_BLANK_POWERDOWN);
 244         pci_dev_put(lpc_dev);
 245
 246         return 0;
 247 }
 248
 249 static struct platform_driver cr_backlight_driver = {
 250         .probe = cr_backlight_probe,
 251         .remove = cr_backlight_remove,
 252         .driver = {
 253                    .name = "cr_backlight",
 254                    },
 255 };
 256
 257 static struct platform_device *crp;
 258
 259 static int __init cr_backlight_init(void)
 260 {
 261         int ret = platform_driver_register(&cr_backlight_driver);
 262
 263         if (ret)
 264                 return ret;
 265
 266         crp = platform_device_register_simple("cr_backlight", -1, NULL, 0);
 267         if (IS_ERR(crp)) {
 268                 platform_driver_unregister(&cr_backlight_driver);
 269                 return PTR_ERR(crp);
 270         }
 271
 272         pr_info("Carillo Ranch Backlight Driver Initialized.\n");
 273
 274         return 0;
 275 }
 276
 277 static void __exit cr_backlight_exit(void)
 278 {
 279         platform_device_unregister(crp);
 280         platform_driver_unregister(&cr_backlight_driver);
 281 }
 282
 283 module_init(cr_backlight_init);
 284 module_exit(cr_backlight_exit);
 285
 286 MODULE_AUTHOR("Tungsten Graphics Inc.");
 287 MODULE_DESCRIPTION("Carillo Ranch Backlight Driver");
 288 MODULE_LICENSE("GPL");