linux/drivers/gpu/drm/mgag200/mgag200_i2c.c
Julia Lemire ce495960ff drm/mgag200: Bug fix: Renesas board now selects native resolution.
Renesas boards were consistently defaulting to the 1024x768 resolution,
regardless of the native resolution of the monitor plugged in.  It was
determined that the EDID of the monitor was not being read.  Since the
DAC is a shared line, in order to read from or write to it we must take
control of the DAC clock.  This can be done by setting the proper
register to one.

This bug fix sets the register MGA1064_GEN_IO_CTL2 to one.  The DAC
control line can be used to determine whether or not a new monitor has
been plugged in.  But since the hotplug feature is not one we will
support, it has been decided to simply leave the register set to one.

Signed-off-by: Julia Lemire <jlemire@matrox.com>
Signed-off-by: Dave Airlie <airlied@redhat.com>
2013-03-08 08:31:49 +10:00

157 lines
3.9 KiB
C

/*
* 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 <airlied@redhat.com>
*/
#include <linux/export.h>
#include <linux/i2c.h>
#include <linux/i2c-algo-bit.h>
#include <drm/drmP.h>
#include "mgag200_drv.h"
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 mga_gpio_setsda(void *data, int state)
{
struct mga_i2c_chan *i2c = data;
struct mga_device *mdev = i2c->dev->dev_private;
mga_i2c_set(mdev, i2c->data, state);
}
static void mga_gpio_setscl(void *data, int state)
{
struct mga_i2c_chan *i2c = data;
struct mga_device *mdev = i2c->dev->dev_private;
mga_i2c_set(mdev, i2c->clock, state);
}
static int mga_gpio_getsda(void *data)
{
struct mga_i2c_chan *i2c = data;
struct mga_device *mdev = i2c->dev->dev_private;
return (mga_i2c_read_gpio(mdev) & i2c->data) ? 1 : 0;
}
static int mga_gpio_getscl(void *data)
{
struct mga_i2c_chan *i2c = data;
struct mga_device *mdev = i2c->dev->dev_private;
return (mga_i2c_read_gpio(mdev) & i2c->clock) ? 1 : 0;
}
struct mga_i2c_chan *mgag200_i2c_create(struct drm_device *dev)
{
struct mga_device *mdev = dev->dev_private;
struct mga_i2c_chan *i2c;
int ret;
int data, clock;
WREG_DAC(MGA1064_GEN_IO_CTL2, 1);
WREG_DAC(MGA1064_GEN_IO_DATA, 0xff);
WREG_DAC(MGA1064_GEN_IO_CTL, 0);
switch (mdev->type) {
case G200_SE_A:
case G200_SE_B:
case G200_EV:
case G200_WB:
data = 1;
clock = 2;
break;
case G200_EH:
case G200_ER:
data = 2;
clock = 1;
break;
default:
data = 2;
clock = 8;
break;
}
i2c = kzalloc(sizeof(struct mga_i2c_chan), GFP_KERNEL);
if (!i2c)
return NULL;
i2c->data = data;
i2c->clock = clock;
i2c->adapter.owner = THIS_MODULE;
i2c->adapter.class = I2C_CLASS_DDC;
i2c->adapter.dev.parent = &dev->pdev->dev;
i2c->dev = dev;
i2c_set_adapdata(&i2c->adapter, i2c);
snprintf(i2c->adapter.name, sizeof(i2c->adapter.name), "mga i2c");
i2c->adapter.algo_data = &i2c->bit;
i2c->bit.udelay = 10;
i2c->bit.timeout = 2;
i2c->bit.data = i2c;
i2c->bit.setsda = mga_gpio_setsda;
i2c->bit.setscl = mga_gpio_setscl;
i2c->bit.getsda = mga_gpio_getsda;
i2c->bit.getscl = mga_gpio_getscl;
ret = i2c_bit_add_bus(&i2c->adapter);
if (ret) {
kfree(i2c);
i2c = NULL;
}
return i2c;
}
void mgag200_i2c_destroy(struct mga_i2c_chan *i2c)
{
if (!i2c)
return;
i2c_del_adapter(&i2c->adapter);
kfree(i2c);
}