linux/drivers/video/savage/savagefb-i2c.c
Jean Delvare 9201a8584c savagefb: speed up the I2C bus
There is no reason to drive the savagefb I2C bus at such a low speed, so bump
it from 12.5 kbps to 50 kbps.  The Intel (i810) and Matrox framebuffer drivers
already run their I2C bus at this speed, and so are the legacy i2c-savage4 and
i2c-prosavage drivers.

Signed-off-by: Jean Delvare <khali@linux-fr.org>
Cc: "Antonino A. Daplas" <adaplas@pol.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-04-28 08:58:38 -07:00

233 lines
5.2 KiB
C

/*
* linux/drivers/video/savage/savagefb-i2c.c - S3 Savage DDC2
*
* Copyright 2004 Antonino A. Daplas <adaplas @pol.net>
*
* Based partly on rivafb-i2c.c
*
* This file is subject to the terms and conditions of the GNU General Public
* License. See the file COPYING in the main directory of this archive
* for more details.
*/
#include <linux/module.h>
#include <linux/kernel.h>
#include <linux/delay.h>
#include <linux/pci.h>
#include <linux/fb.h>
#include <asm/io.h>
#include "savagefb.h"
#define SAVAGE_DDC 0x50
#define VGA_CR_IX 0x3d4
#define VGA_CR_DATA 0x3d5
#define CR_SERIAL1 0xa0 /* I2C serial communications interface */
#define MM_SERIAL1 0xff20
#define CR_SERIAL2 0xb1 /* DDC2 monitor communications interface */
/* based on vt8365 documentation */
#define PROSAVAGE_I2C_ENAB 0x10
#define PROSAVAGE_I2C_SCL_OUT 0x01
#define PROSAVAGE_I2C_SDA_OUT 0x02
#define PROSAVAGE_I2C_SCL_IN 0x04
#define PROSAVAGE_I2C_SDA_IN 0x08
#define SAVAGE4_I2C_ENAB 0x00000020
#define SAVAGE4_I2C_SCL_OUT 0x00000001
#define SAVAGE4_I2C_SDA_OUT 0x00000002
#define SAVAGE4_I2C_SCL_IN 0x00000008
#define SAVAGE4_I2C_SDA_IN 0x00000010
static void savage4_gpio_setscl(void *data, int val)
{
struct savagefb_i2c_chan *chan = data;
unsigned int r;
r = readl(chan->ioaddr + chan->reg);
if(val)
r |= SAVAGE4_I2C_SCL_OUT;
else
r &= ~SAVAGE4_I2C_SCL_OUT;
writel(r, chan->ioaddr + chan->reg);
readl(chan->ioaddr + chan->reg); /* flush posted write */
}
static void savage4_gpio_setsda(void *data, int val)
{
struct savagefb_i2c_chan *chan = data;
unsigned int r;
r = readl(chan->ioaddr + chan->reg);
if(val)
r |= SAVAGE4_I2C_SDA_OUT;
else
r &= ~SAVAGE4_I2C_SDA_OUT;
writel(r, chan->ioaddr + chan->reg);
readl(chan->ioaddr + chan->reg); /* flush posted write */
}
static int savage4_gpio_getscl(void *data)
{
struct savagefb_i2c_chan *chan = data;
return (0 != (readl(chan->ioaddr + chan->reg) & SAVAGE4_I2C_SCL_IN));
}
static int savage4_gpio_getsda(void *data)
{
struct savagefb_i2c_chan *chan = data;
return (0 != (readl(chan->ioaddr + chan->reg) & SAVAGE4_I2C_SDA_IN));
}
static void prosavage_gpio_setscl(void* data, int val)
{
struct savagefb_i2c_chan *chan = data;
u32 r;
r = VGArCR(chan->reg, chan->par);
r |= PROSAVAGE_I2C_ENAB;
if (val) {
r |= PROSAVAGE_I2C_SCL_OUT;
} else {
r &= ~PROSAVAGE_I2C_SCL_OUT;
}
VGAwCR(chan->reg, r, chan->par);
}
static void prosavage_gpio_setsda(void* data, int val)
{
struct savagefb_i2c_chan *chan = data;
unsigned int r;
r = VGArCR(chan->reg, chan->par);
r |= PROSAVAGE_I2C_ENAB;
if (val) {
r |= PROSAVAGE_I2C_SDA_OUT;
} else {
r &= ~PROSAVAGE_I2C_SDA_OUT;
}
VGAwCR(chan->reg, r, chan->par);
}
static int prosavage_gpio_getscl(void* data)
{
struct savagefb_i2c_chan *chan = data;
return (VGArCR(chan->reg, chan->par) & PROSAVAGE_I2C_SCL_IN) ? 1 : 0;
}
static int prosavage_gpio_getsda(void* data)
{
struct savagefb_i2c_chan *chan = data;
return (VGArCR(chan->reg, chan->par) & PROSAVAGE_I2C_SDA_IN) ? 1 : 0;
}
static int savage_setup_i2c_bus(struct savagefb_i2c_chan *chan,
const char *name)
{
int rc = 0;
if (chan->par) {
strcpy(chan->adapter.name, name);
chan->adapter.owner = THIS_MODULE;
chan->adapter.id = I2C_HW_B_SAVAGE;
chan->adapter.algo_data = &chan->algo;
chan->adapter.dev.parent = &chan->par->pcidev->dev;
chan->algo.udelay = 10;
chan->algo.timeout = 20;
chan->algo.data = chan;
i2c_set_adapdata(&chan->adapter, chan);
/* Raise SCL and SDA */
chan->algo.setsda(chan, 1);
chan->algo.setscl(chan, 1);
udelay(20);
rc = i2c_bit_add_bus(&chan->adapter);
if (rc == 0)
dev_dbg(&chan->par->pcidev->dev,
"I2C bus %s registered.\n", name);
else
dev_warn(&chan->par->pcidev->dev,
"Failed to register I2C bus %s.\n", name);
} else
chan->par = NULL;
return rc;
}
void savagefb_create_i2c_busses(struct fb_info *info)
{
struct savagefb_par *par = info->par;
par->chan.par = par;
switch(info->fix.accel) {
case FB_ACCEL_PROSAVAGE_DDRK:
case FB_ACCEL_PROSAVAGE_PM:
par->chan.reg = CR_SERIAL2;
par->chan.ioaddr = par->mmio.vbase;
par->chan.algo.setsda = prosavage_gpio_setsda;
par->chan.algo.setscl = prosavage_gpio_setscl;
par->chan.algo.getsda = prosavage_gpio_getsda;
par->chan.algo.getscl = prosavage_gpio_getscl;
break;
case FB_ACCEL_SAVAGE4:
case FB_ACCEL_SAVAGE2000:
par->chan.reg = 0xff20;
par->chan.ioaddr = par->mmio.vbase;
par->chan.algo.setsda = savage4_gpio_setsda;
par->chan.algo.setscl = savage4_gpio_setscl;
par->chan.algo.getsda = savage4_gpio_getsda;
par->chan.algo.getscl = savage4_gpio_getscl;
break;
default:
par->chan.par = NULL;
}
savage_setup_i2c_bus(&par->chan, "SAVAGE DDC2");
}
void savagefb_delete_i2c_busses(struct fb_info *info)
{
struct savagefb_par *par = info->par;
if (par->chan.par)
i2c_del_adapter(&par->chan.adapter);
par->chan.par = NULL;
}
int savagefb_probe_i2c_connector(struct fb_info *info, u8 **out_edid)
{
struct savagefb_par *par = info->par;
u8 *edid;
if (par->chan.par)
edid = fb_ddc_read(&par->chan.adapter);
else
edid = NULL;
if (!edid) {
/* try to get from firmware */
const u8 *e = fb_firmware_edid(info->device);
if (e)
edid = kmemdup(e, EDID_LENGTH, GFP_KERNEL);
}
*out_edid = edid;
return (edid) ? 0 : 1;
}
MODULE_LICENSE("GPL");