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1/*2 * Copyright 2012 Red Hat Inc.3 *4 * Permission is hereby granted, free of charge, to any person obtaining a5 * copy of this software and associated documentation files (the6 * "Software"), to deal in the Software without restriction, including7 * without limitation the rights to use, copy, modify, merge, publish,8 * distribute, sub license, and/or sell copies of the Software, and to9 * permit persons to whom the Software is furnished to do so, subject to10 * the following conditions:11 *12 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR13 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,14 * FITNESS FOR A PARTICULAR PURPOSE AND NON-INFRINGEMENT. IN NO EVENT SHALL15 * THE COPYRIGHT HOLDERS, AUTHORS AND/OR ITS SUPPLIERS BE LIABLE FOR ANY CLAIM,16 * DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR17 * OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE18 * USE OR OTHER DEALINGS IN THE SOFTWARE.19 *20 * The above copyright notice and this permission notice (including the21 * next paragraph) shall be included in all copies or substantial portions22 * of the Software.23 *24 */25/*26 * Authors: Dave Airlie <airlied@redhat.com>27 */28 29#include <linux/export.h>30#include <linux/i2c-algo-bit.h>31#include <linux/i2c.h>32#include <linux/pci.h>33 34#include <drm/drm_managed.h>35 36#include "mgag200_ddc.h"37#include "mgag200_drv.h"38 39struct mgag200_ddc {40 struct mga_device *mdev;41 42 int data;43 int clock;44 45 struct i2c_algo_bit_data bit;46 struct i2c_adapter adapter;47};48 49static int mga_i2c_read_gpio(struct mga_device *mdev)50{51 WREG8(DAC_INDEX, MGA1064_GEN_IO_DATA);52 return RREG8(DAC_DATA);53}54 55static void mga_i2c_set_gpio(struct mga_device *mdev, int mask, int val)56{57 int tmp;58 59 WREG8(DAC_INDEX, MGA1064_GEN_IO_CTL);60 tmp = (RREG8(DAC_DATA) & mask) | val;61 WREG_DAC(MGA1064_GEN_IO_CTL, tmp);62 WREG_DAC(MGA1064_GEN_IO_DATA, 0);63}64 65static inline void mga_i2c_set(struct mga_device *mdev, int mask, int state)66{67 if (state)68 state = 0;69 else70 state = mask;71 mga_i2c_set_gpio(mdev, ~mask, state);72}73 74static void mgag200_ddc_algo_bit_data_setsda(void *data, int state)75{76 struct mgag200_ddc *ddc = data;77 78 mga_i2c_set(ddc->mdev, ddc->data, state);79}80 81static void mgag200_ddc_algo_bit_data_setscl(void *data, int state)82{83 struct mgag200_ddc *ddc = data;84 85 mga_i2c_set(ddc->mdev, ddc->clock, state);86}87 88static int mgag200_ddc_algo_bit_data_getsda(void *data)89{90 struct mgag200_ddc *ddc = data;91 92 return (mga_i2c_read_gpio(ddc->mdev) & ddc->data) ? 1 : 0;93}94 95static int mgag200_ddc_algo_bit_data_getscl(void *data)96{97 struct mgag200_ddc *ddc = data;98 99 return (mga_i2c_read_gpio(ddc->mdev) & ddc->clock) ? 1 : 0;100}101 102static int mgag200_ddc_algo_bit_data_pre_xfer(struct i2c_adapter *adapter)103{104 struct mgag200_ddc *ddc = i2c_get_adapdata(adapter);105 struct mga_device *mdev = ddc->mdev;106 107 /*108 * Protect access to I/O registers from concurrent modesetting109 * by acquiring the I/O-register lock.110 */111 mutex_lock(&mdev->rmmio_lock);112 113 return 0;114}115 116static void mgag200_ddc_algo_bit_data_post_xfer(struct i2c_adapter *adapter)117{118 struct mgag200_ddc *ddc = i2c_get_adapdata(adapter);119 struct mga_device *mdev = ddc->mdev;120 121 mutex_unlock(&mdev->rmmio_lock);122}123 124static void mgag200_ddc_release(struct drm_device *dev, void *res)125{126 struct mgag200_ddc *ddc = res;127 128 i2c_del_adapter(&ddc->adapter);129}130 131struct i2c_adapter *mgag200_ddc_create(struct mga_device *mdev)132{133 struct drm_device *dev = &mdev->base;134 const struct mgag200_device_info *info = mdev->info;135 struct mgag200_ddc *ddc;136 struct i2c_algo_bit_data *bit;137 struct i2c_adapter *adapter;138 int ret;139 140 ddc = drmm_kzalloc(dev, sizeof(*ddc), GFP_KERNEL);141 if (!ddc)142 return ERR_PTR(-ENOMEM);143 144 WREG_DAC(MGA1064_GEN_IO_CTL2, 1);145 WREG_DAC(MGA1064_GEN_IO_DATA, 0xff);146 WREG_DAC(MGA1064_GEN_IO_CTL, 0);147 148 ddc->mdev = mdev;149 ddc->data = BIT(info->i2c.data_bit);150 ddc->clock = BIT(info->i2c.clock_bit);151 152 bit = &ddc->bit;153 bit->data = ddc;154 bit->setsda = mgag200_ddc_algo_bit_data_setsda;155 bit->setscl = mgag200_ddc_algo_bit_data_setscl;156 bit->getsda = mgag200_ddc_algo_bit_data_getsda;157 bit->getscl = mgag200_ddc_algo_bit_data_getscl;158 bit->pre_xfer = mgag200_ddc_algo_bit_data_pre_xfer;159 bit->post_xfer = mgag200_ddc_algo_bit_data_post_xfer;160 bit->udelay = 10;161 bit->timeout = usecs_to_jiffies(2200);162 163 adapter = &ddc->adapter;164 adapter->owner = THIS_MODULE;165 adapter->algo_data = bit;166 adapter->dev.parent = dev->dev;167 snprintf(adapter->name, sizeof(adapter->name), "Matrox DDC bus");168 i2c_set_adapdata(adapter, ddc);169 170 ret = i2c_bit_add_bus(adapter);171 if (ret)172 return ERR_PTR(ret);173 174 ret = drmm_add_action_or_reset(dev, mgag200_ddc_release, ddc);175 if (ret)176 return ERR_PTR(ret);177 178 return adapter;179}180