| /* |
| * psb backlight interface |
| * |
| * Copyright (c) 2009, Intel Corporation. |
| * |
| * This program is free software; you can redistribute it and/or modify it |
| * under the terms and conditions of the GNU General Public License, |
| * version 2, as published by the Free Software Foundation. |
| * |
| * This program is distributed in the hope it will be useful, but WITHOUT |
| * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or |
| * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for |
| * more details. |
| * |
| * You should have received a copy of the GNU General Public License along with |
| * this program; if not, write to the Free Software Foundation, Inc., |
| * 51 Franklin St - Fifth Floor, Boston, MA 02110-1301 USA. |
| * |
| * Authors: Eric Knopp |
| * |
| */ |
| |
| #include <linux/backlight.h> |
| #include <linux/version.h> |
| #include "psb_drv.h" |
| #include "psb_intel_reg.h" |
| #include "psb_intel_drv.h" |
| #include "psb_intel_bios.h" |
| #include "psb_powermgmt.h" |
| |
| #define MRST_BLC_MAX_PWM_REG_FREQ 0xFFFF |
| #define BLC_PWM_PRECISION_FACTOR 100 /* 10000000 */ |
| #define BLC_PWM_FREQ_CALC_CONSTANT 32 |
| #define MHz 1000000 |
| #define BRIGHTNESS_MIN_LEVEL 1 |
| #define BRIGHTNESS_MAX_LEVEL 100 |
| #define BRIGHTNESS_MASK 0xFF |
| #define BLC_POLARITY_NORMAL 0 |
| #define BLC_POLARITY_INVERSE 1 |
| #define BLC_ADJUSTMENT_MAX 100 |
| |
| #define PSB_BLC_PWM_PRECISION_FACTOR 10 |
| #define PSB_BLC_MAX_PWM_REG_FREQ 0xFFFE |
| #define PSB_BLC_MIN_PWM_REG_FREQ 0x2 |
| |
| #define PSB_BACKLIGHT_PWM_POLARITY_BIT_CLEAR (0xFFFE) |
| #define PSB_BACKLIGHT_PWM_CTL_SHIFT (16) |
| |
| static int psb_brightness; |
| static struct backlight_device *psb_backlight_device; |
| static u8 blc_brightnesscmd; |
| static u8 blc_pol; |
| static u8 blc_type; |
| |
| int psb_set_brightness(struct backlight_device *bd) |
| { |
| struct drm_device *dev = bl_get_data(psb_backlight_device); |
| int level = bd->props.brightness; |
| |
| DRM_DEBUG_DRIVER("backlight level set to %d\n", level); |
| |
| /* Perform value bounds checking */ |
| if (level < BRIGHTNESS_MIN_LEVEL) |
| level = BRIGHTNESS_MIN_LEVEL; |
| |
| psb_intel_lvds_set_brightness(dev, level); |
| psb_brightness = level; |
| return 0; |
| } |
| |
| int psb_get_brightness(struct backlight_device *bd) |
| { |
| DRM_DEBUG_DRIVER("brightness = 0x%x\n", psb_brightness); |
| |
| /* return locally cached var instead of HW read (due to DPST etc.) */ |
| /* FIXME: ideally return actual value in case firmware fiddled with |
| it */ |
| return psb_brightness; |
| } |
| |
| static const struct backlight_ops psb_ops = { |
| .get_brightness = psb_get_brightness, |
| .update_status = psb_set_brightness, |
| }; |
| |
| static int device_backlight_init(struct drm_device *dev) |
| { |
| unsigned long core_clock; |
| /* u32 bl_max_freq; */ |
| /* unsigned long value; */ |
| u16 bl_max_freq; |
| uint32_t value; |
| uint32_t blc_pwm_precision_factor; |
| struct drm_psb_private *dev_priv = dev->dev_private; |
| |
| /* get bl_max_freq and pol from dev_priv*/ |
| if (!dev_priv->lvds_bl) { |
| DRM_ERROR("Has no valid LVDS backlight info\n"); |
| return 1; |
| } |
| bl_max_freq = dev_priv->lvds_bl->freq; |
| blc_pol = dev_priv->lvds_bl->pol; |
| blc_pwm_precision_factor = PSB_BLC_PWM_PRECISION_FACTOR; |
| blc_brightnesscmd = dev_priv->lvds_bl->brightnesscmd; |
| blc_type = dev_priv->lvds_bl->type; |
| |
| core_clock = dev_priv->core_freq; |
| |
| value = (core_clock * MHz) / BLC_PWM_FREQ_CALC_CONSTANT; |
| value *= blc_pwm_precision_factor; |
| value /= bl_max_freq; |
| value /= blc_pwm_precision_factor; |
| |
| if (ospm_power_using_hw_begin(OSPM_DISPLAY_ISLAND, |
| OSPM_UHB_ONLY_IF_ON)) { |
| /* Check: may be MFLD only */ |
| if ( |
| value > (unsigned long long)PSB_BLC_MAX_PWM_REG_FREQ || |
| value < (unsigned long long)PSB_BLC_MIN_PWM_REG_FREQ) |
| return 2; |
| else { |
| value &= PSB_BACKLIGHT_PWM_POLARITY_BIT_CLEAR; |
| REG_WRITE(BLC_PWM_CTL, |
| (value << PSB_BACKLIGHT_PWM_CTL_SHIFT) | |
| (value)); |
| } |
| ospm_power_using_hw_end(OSPM_DISPLAY_ISLAND); |
| } |
| return 0; |
| } |
| |
| int psb_backlight_init(struct drm_device *dev) |
| { |
| #ifdef CONFIG_BACKLIGHT_CLASS_DEVICE |
| int ret = 0; |
| |
| struct backlight_properties props; |
| memset(&props, 0, sizeof(struct backlight_properties)); |
| props.max_brightness = BRIGHTNESS_MAX_LEVEL; |
| |
| psb_backlight_device = backlight_device_register("psb-bl", NULL, |
| (void *)dev, &psb_ops, &props); |
| if (IS_ERR(psb_backlight_device)) |
| return PTR_ERR(psb_backlight_device); |
| |
| ret = device_backlight_init(dev); |
| if (ret < 0) |
| return ret; |
| |
| psb_backlight_device->props.brightness = BRIGHTNESS_MAX_LEVEL; |
| psb_backlight_device->props.max_brightness = BRIGHTNESS_MAX_LEVEL; |
| backlight_update_status(psb_backlight_device); |
| #endif |
| return 0; |
| } |
| |
| void psb_backlight_exit(void) |
| { |
| #ifdef CONFIG_BACKLIGHT_CLASS_DEVICE |
| psb_backlight_device->props.brightness = 0; |
| backlight_update_status(psb_backlight_device); |
| backlight_device_unregister(psb_backlight_device); |
| #endif |
| } |
| |
| struct backlight_device *psb_get_backlight_device(void) |
| { |
| return psb_backlight_device; |
| } |