176 lines · c
1 /*-*- linux-c -*-2 * linux/drivers/video/i810-i2c.c -- Intel 810/815 I2C support3 *4 * Copyright (C) 2004 Antonino Daplas<adaplas@pol.net>5 * All Rights Reserved6 *7 * This file is subject to the terms and conditions of the GNU General Public8 * License. See the file COPYING in the main directory of this archive for9 * more details.10 */11#include <linux/module.h>12#include <linux/kernel.h>13#include <linux/delay.h>14#include <linux/gfp.h>15#include <linux/pci.h>16#include <linux/fb.h>17#include "i810.h"18#include "i810_regs.h"19#include "i810_main.h"20#include "../edid.h"21 22/* bit locations in the registers */23#define SCL_DIR_MASK 0x000124#define SCL_DIR 0x000225#define SCL_VAL_MASK 0x000426#define SCL_VAL_OUT 0x000827#define SCL_VAL_IN 0x001028#define SDA_DIR_MASK 0x010029#define SDA_DIR 0x020030#define SDA_VAL_MASK 0x040031#define SDA_VAL_OUT 0x080032#define SDA_VAL_IN 0x100033 34#define DEBUG /* define this for verbose EDID parsing output */35 36#ifdef DEBUG37#define DPRINTK(fmt, args...) printk(fmt,## args)38#else39#define DPRINTK(fmt, args...)40#endif41 42static void i810i2c_setscl(void *data, int state)43{44 struct i810fb_i2c_chan *chan = data;45 struct i810fb_par *par = chan->par;46 u8 __iomem *mmio = par->mmio_start_virtual;47 48 if (state)49 i810_writel(mmio, chan->ddc_base, SCL_DIR_MASK | SCL_VAL_MASK);50 else51 i810_writel(mmio, chan->ddc_base, SCL_DIR | SCL_DIR_MASK | SCL_VAL_MASK);52 i810_readl(mmio, chan->ddc_base); /* flush posted write */53}54 55static void i810i2c_setsda(void *data, int state)56{57 struct i810fb_i2c_chan *chan = data;58 struct i810fb_par *par = chan->par;59 u8 __iomem *mmio = par->mmio_start_virtual;60 61 if (state)62 i810_writel(mmio, chan->ddc_base, SDA_DIR_MASK | SDA_VAL_MASK);63 else64 i810_writel(mmio, chan->ddc_base, SDA_DIR | SDA_DIR_MASK | SDA_VAL_MASK);65 i810_readl(mmio, chan->ddc_base); /* flush posted write */66}67 68static int i810i2c_getscl(void *data)69{70 struct i810fb_i2c_chan *chan = data;71 struct i810fb_par *par = chan->par;72 u8 __iomem *mmio = par->mmio_start_virtual;73 74 i810_writel(mmio, chan->ddc_base, SCL_DIR_MASK);75 i810_writel(mmio, chan->ddc_base, 0);76 return ((i810_readl(mmio, chan->ddc_base) & SCL_VAL_IN) != 0);77}78 79static int i810i2c_getsda(void *data)80{81 struct i810fb_i2c_chan *chan = data;82 struct i810fb_par *par = chan->par;83 u8 __iomem *mmio = par->mmio_start_virtual;84 85 i810_writel(mmio, chan->ddc_base, SDA_DIR_MASK);86 i810_writel(mmio, chan->ddc_base, 0);87 return ((i810_readl(mmio, chan->ddc_base) & SDA_VAL_IN) != 0);88}89 90static int i810_setup_i2c_bus(struct i810fb_i2c_chan *chan, const char *name)91{92 int rc;93 94 strcpy(chan->adapter.name, name);95 chan->adapter.owner = THIS_MODULE;96 chan->adapter.algo_data = &chan->algo;97 chan->adapter.dev.parent = &chan->par->dev->dev;98 chan->algo.setsda = i810i2c_setsda;99 chan->algo.setscl = i810i2c_setscl;100 chan->algo.getsda = i810i2c_getsda;101 chan->algo.getscl = i810i2c_getscl;102 chan->algo.udelay = 10;103 chan->algo.timeout = (HZ/2);104 chan->algo.data = chan;105 106 i2c_set_adapdata(&chan->adapter, chan);107 108 /* Raise SCL and SDA */109 chan->algo.setsda(chan, 1);110 chan->algo.setscl(chan, 1);111 udelay(20);112 113 rc = i2c_bit_add_bus(&chan->adapter);114 115 if (rc == 0)116 dev_dbg(&chan->par->dev->dev, "I2C bus %s registered.\n",name);117 else {118 dev_warn(&chan->par->dev->dev, "Failed to register I2C bus "119 "%s.\n", name);120 chan->par = NULL;121 }122 123 return rc;124}125 126void i810_create_i2c_busses(struct i810fb_par *par)127{128 par->chan[0].par = par;129 par->chan[1].par = par;130 par->chan[2].par = par;131 132 par->chan[0].ddc_base = GPIOA;133 i810_setup_i2c_bus(&par->chan[0], "I810-DDC");134 par->chan[1].ddc_base = GPIOB;135 i810_setup_i2c_bus(&par->chan[1], "I810-I2C");136 par->chan[2].ddc_base = GPIOC;137 i810_setup_i2c_bus(&par->chan[2], "I810-GPIOC");138}139 140void i810_delete_i2c_busses(struct i810fb_par *par)141{142 if (par->chan[0].par)143 i2c_del_adapter(&par->chan[0].adapter);144 par->chan[0].par = NULL;145 146 if (par->chan[1].par)147 i2c_del_adapter(&par->chan[1].adapter);148 par->chan[1].par = NULL;149 150 if (par->chan[2].par)151 i2c_del_adapter(&par->chan[2].adapter);152 par->chan[2].par = NULL;153}154 155int i810_probe_i2c_connector(struct fb_info *info, u8 **out_edid, int conn)156{157 struct i810fb_par *par = info->par;158 u8 *edid = NULL;159 160 DPRINTK("i810-i2c: Probe DDC%i Bus\n", conn+1);161 if (conn < par->ddc_num) {162 edid = fb_ddc_read(&par->chan[conn].adapter);163 } else {164 const u8 *e = fb_firmware_edid(info->device);165 166 if (e != NULL) {167 DPRINTK("i810-i2c: Getting EDID from BIOS\n");168 edid = kmemdup(e, EDID_LENGTH, GFP_KERNEL);169 }170 }171 172 *out_edid = edid;173 174 return (edid) ? 0 : 1;175}176