/* * Copyright (c) 2006 Dave Airlie * Copyright © 2006-2008 Intel Corporation * Jesse Barnes * * Permission is hereby granted, free of charge, to any person obtaining a * copy of this software and associated documentation files (the "Software"), * to deal in the Software without restriction, including without limitation * the rights to use, copy, modify, merge, publish, distribute, sublicense, * and/or sell copies of the Software, and to permit persons to whom the * Software is furnished to do so, subject to the following conditions: * * The above copyright notice and this permission notice (including the next * paragraph) shall be included in all copies or substantial portions of the * Software. * * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER * DEALINGS IN THE SOFTWARE. * * Authors: * Eric Anholt */ #include #include #include #include "drmP.h" #include "drm.h" #include "intel_drv.h" #include "i915_drm.h" #include "i915_drv.h" /* * Intel GPIO access functions */ #define I2C_RISEFALL_TIME 20 static int get_clock(void *data) { struct intel_i2c_chan *chan = data; struct drm_i915_private *dev_priv = chan->drm_dev->dev_private; u32 val; val = I915_READ(chan->reg); return ((val & GPIO_CLOCK_VAL_IN) != 0); } static int get_data(void *data) { struct intel_i2c_chan *chan = data; struct drm_i915_private *dev_priv = chan->drm_dev->dev_private; u32 val; val = I915_READ(chan->reg); return ((val & GPIO_DATA_VAL_IN) != 0); } static void set_clock(void *data, int state_high) { struct intel_i2c_chan *chan = data; struct drm_device *dev = chan->drm_dev; struct drm_i915_private *dev_priv = chan->drm_dev->dev_private; u32 reserved = 0, clock_bits; /* On most chips, these bits must be preserved in software. */ if (!IS_I830(dev) && !IS_845G(dev)) reserved = I915_READ(chan->reg) & (GPIO_DATA_PULLUP_DISABLE | GPIO_CLOCK_PULLUP_DISABLE); if (state_high) clock_bits = GPIO_CLOCK_DIR_IN | GPIO_CLOCK_DIR_MASK; else clock_bits = GPIO_CLOCK_DIR_OUT | GPIO_CLOCK_DIR_MASK | GPIO_CLOCK_VAL_MASK; I915_WRITE(chan->reg, reserved | clock_bits); udelay(I2C_RISEFALL_TIME); /* wait for the line to change state */ } static void set_data(void *data, int state_high) { struct intel_i2c_chan *chan = data; struct drm_device *dev = chan->drm_dev; struct drm_i915_private *dev_priv = chan->drm_dev->dev_private; u32 reserved = 0, data_bits; /* On most chips, these bits must be preserved in software. */ if (!IS_I830(dev) && !IS_845G(dev)) reserved = I915_READ(chan->reg) & (GPIO_DATA_PULLUP_DISABLE | GPIO_CLOCK_PULLUP_DISABLE); if (state_high) data_bits = GPIO_DATA_DIR_IN | GPIO_DATA_DIR_MASK; else data_bits = GPIO_DATA_DIR_OUT | GPIO_DATA_DIR_MASK | GPIO_DATA_VAL_MASK; I915_WRITE(chan->reg, reserved | data_bits); udelay(I2C_RISEFALL_TIME); /* wait for the line to change state */ } /** * intel_i2c_create - instantiate an Intel i2c bus using the specified GPIO reg * @dev: DRM device * @output: driver specific output device * @reg: GPIO reg to use * @name: name for this bus * * Creates and registers a new i2c bus with the Linux i2c layer, for use * in output probing and control (e.g. DDC or SDVO control functions). * * Possible values for @reg include: * %GPIOA * %GPIOB * %GPIOC * %GPIOD * %GPIOE * %GPIOF * %GPIOG * %GPIOH * see PRM for details on how these different busses are used. */ struct intel_i2c_chan *intel_i2c_create(struct drm_device *dev, const u32 reg, const char *name) { struct intel_i2c_chan *chan; chan = kzalloc(sizeof(struct intel_i2c_chan), GFP_KERNEL); if (!chan) goto out_free; chan->drm_dev = dev; chan->reg = reg; snprintf(chan->adapter.name, I2C_NAME_SIZE, "intel drm %s", name); chan->adapter.owner = THIS_MODULE; #ifndef I2C_HW_B_INTELFB #define I2C_HW_B_INTELFB I2C_HW_B_I810 #endif chan->adapter.id = I2C_HW_B_INTELFB; chan->adapter.algo_data = &chan->algo; chan->adapter.dev.parent = &dev->pdev->dev; chan->algo.setsda = set_data; chan->algo.setscl = set_clock; chan->algo.getsda = get_data; chan->algo.getscl = get_clock; chan->algo.udelay = 20; chan->algo.timeout = usecs_to_jiffies(2200); chan->algo.data = chan; i2c_set_adapdata(&chan->adapter, chan); if(i2c_bit_add_bus(&chan->adapter)) goto out_free; /* JJJ: raise SCL and SDA? */ set_data(chan, 1); set_clock(chan, 1); udelay(20); return chan; out_free: kfree(chan); return NULL; } /** * intel_i2c_destroy - unregister and free i2c bus resources * @output: channel to free * * Unregister the adapter from the i2c layer, then free the structure. */ void intel_i2c_destroy(struct intel_i2c_chan *chan) { if (!chan) return; i2c_del_adapter(&chan->adapter); kfree(chan); }