/*
* Copyright 2012 Red Hat Inc.
*
* 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, sub license, 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 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 NON-INFRINGEMENT. IN NO EVENT SHALL
* THE COPYRIGHT HOLDERS, AUTHORS AND/OR ITS SUPPLIERS 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.
*
* The above copyright notice and this permission notice (including the
* next paragraph) shall be included in all copies or substantial portions
* of the Software.
*
*/
/*
* Authors: Dave Airlie <[email protected]>
*/
#include <linux/export.h>
#include <linux/i2c-algo-bit.h>
#include <linux/i2c.h>
#include <linux/pci.h>
#include <drm/drm_managed.h>
#include "mgag200_ddc.h"
#include "mgag200_drv.h"
struct mgag200_ddc {
struct mga_device *mdev;
int data;
int clock;
struct i2c_algo_bit_data bit;
struct i2c_adapter adapter;
};
static int mga_i2c_read_gpio(struct mga_device *mdev)
{
WREG8(DAC_INDEX, MGA1064_GEN_IO_DATA);
return RREG8(DAC_DATA);
}
static void mga_i2c_set_gpio(struct mga_device *mdev, int mask, int val)
{
int tmp;
WREG8(DAC_INDEX, MGA1064_GEN_IO_CTL);
tmp = (RREG8(DAC_DATA) & mask) | val;
WREG_DAC(MGA1064_GEN_IO_CTL, tmp);
WREG_DAC(MGA1064_GEN_IO_DATA, 0);
}
static inline void mga_i2c_set(struct mga_device *mdev, int mask, int state)
{
if (state)
state = 0;
else
state = mask;
mga_i2c_set_gpio(mdev, ~mask, state);
}
static void mgag200_ddc_algo_bit_data_setsda(void *data, int state)
{
struct mgag200_ddc *ddc = data;
mga_i2c_set(ddc->mdev, ddc->data, state);
}
static void mgag200_ddc_algo_bit_data_setscl(void *data, int state)
{
struct mgag200_ddc *ddc = data;
mga_i2c_set(ddc->mdev, ddc->clock, state);
}
static int mgag200_ddc_algo_bit_data_getsda(void *data)
{
struct mgag200_ddc *ddc = data;
return (mga_i2c_read_gpio(ddc->mdev) & ddc->data) ? 1 : 0;
}
static int mgag200_ddc_algo_bit_data_getscl(void *data)
{
struct mgag200_ddc *ddc = data;
return (mga_i2c_read_gpio(ddc->mdev) & ddc->clock) ? 1 : 0;
}
static int mgag200_ddc_algo_bit_data_pre_xfer(struct i2c_adapter *adapter)
{
struct mgag200_ddc *ddc = i2c_get_adapdata(adapter);
struct mga_device *mdev = ddc->mdev;
/*
* Protect access to I/O registers from concurrent modesetting
* by acquiring the I/O-register lock.
*/
mutex_lock(&mdev->rmmio_lock);
return 0;
}
static void mgag200_ddc_algo_bit_data_post_xfer(struct i2c_adapter *adapter)
{
struct mgag200_ddc *ddc = i2c_get_adapdata(adapter);
struct mga_device *mdev = ddc->mdev;
mutex_unlock(&mdev->rmmio_lock);
}
static void mgag200_ddc_release(struct drm_device *dev, void *res)
{
struct mgag200_ddc *ddc = res;
i2c_del_adapter(&ddc->adapter);
}
struct i2c_adapter *mgag200_ddc_create(struct mga_device *mdev)
{
struct drm_device *dev = &mdev->base;
const struct mgag200_device_info *info = mdev->info;
struct mgag200_ddc *ddc;
struct i2c_algo_bit_data *bit;
struct i2c_adapter *adapter;
int ret;
ddc = drmm_kzalloc(dev, sizeof(*ddc), GFP_KERNEL);
if (!ddc)
return ERR_PTR(-ENOMEM);
WREG_DAC(MGA1064_GEN_IO_CTL2, 1);
WREG_DAC(MGA1064_GEN_IO_DATA, 0xff);
WREG_DAC(MGA1064_GEN_IO_CTL, 0);
ddc->mdev = mdev;
ddc->data = BIT(info->i2c.data_bit);
ddc->clock = BIT(info->i2c.clock_bit);
bit = &ddc->bit;
bit->data = ddc;
bit->setsda = mgag200_ddc_algo_bit_data_setsda;
bit->setscl = mgag200_ddc_algo_bit_data_setscl;
bit->getsda = mgag200_ddc_algo_bit_data_getsda;
bit->getscl = mgag200_ddc_algo_bit_data_getscl;
bit->pre_xfer = mgag200_ddc_algo_bit_data_pre_xfer;
bit->post_xfer = mgag200_ddc_algo_bit_data_post_xfer;
bit->udelay = 10;
bit->timeout = usecs_to_jiffies(2200);
adapter = &ddc->adapter;
adapter->owner = THIS_MODULE;
adapter->algo_data = bit;
adapter->dev.parent = dev->dev;
snprintf(adapter->name, sizeof(adapter->name), "Matrox DDC bus");
i2c_set_adapdata(adapter, ddc);
ret = i2c_bit_add_bus(adapter);
if (ret)
return ERR_PTR(ret);
ret = drmm_add_action_or_reset(dev, mgag200_ddc_release, ddc);
if (ret)
return ERR_PTR(ret);
return adapter;
}
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