1 /* 2 * linux/drivers/video/nvidia/nvidia-i2c.c - nVidia i2c 3 * 4 * Copyright 2004 Antonino A. Daplas <adaplas @pol.net> 5 * 6 * Based on rivafb-i2c.c 7 * 8 * This file is subject to the terms and conditions of the GNU General Public 9 * License. See the file COPYING in the main directory of this archive 10 * for more details. 11 */ 12 13 #include <linux/module.h> 14 #include <linux/kernel.h> 15 #include <linux/delay.h> 16 #include <linux/gfp.h> 17 #include <linux/pci.h> 18 #include <linux/fb.h> 19 20 #include <asm/io.h> 21 22 #include "nv_type.h" 23 #include "nv_local.h" 24 #include "nv_proto.h" 25 26 #include "../edid.h" 27 28 static void nvidia_gpio_setscl(void *data, int state) 29 { 30 struct nvidia_i2c_chan *chan = data; 31 struct nvidia_par *par = chan->par; 32 u32 val; 33 34 val = NVReadCrtc(par, chan->ddc_base + 1) & 0xf0; 35 36 if (state) 37 val |= 0x20; 38 else 39 val &= ~0x20; 40 41 NVWriteCrtc(par, chan->ddc_base + 1, val | 0x01); 42 } 43 44 static void nvidia_gpio_setsda(void *data, int state) 45 { 46 struct nvidia_i2c_chan *chan = data; 47 struct nvidia_par *par = chan->par; 48 u32 val; 49 50 val = NVReadCrtc(par, chan->ddc_base + 1) & 0xf0; 51 52 if (state) 53 val |= 0x10; 54 else 55 val &= ~0x10; 56 57 NVWriteCrtc(par, chan->ddc_base + 1, val | 0x01); 58 } 59 60 static int nvidia_gpio_getscl(void *data) 61 { 62 struct nvidia_i2c_chan *chan = data; 63 struct nvidia_par *par = chan->par; 64 u32 val = 0; 65 66 if (NVReadCrtc(par, chan->ddc_base) & 0x04) 67 val = 1; 68 69 return val; 70 } 71 72 static int nvidia_gpio_getsda(void *data) 73 { 74 struct nvidia_i2c_chan *chan = data; 75 struct nvidia_par *par = chan->par; 76 u32 val = 0; 77 78 if (NVReadCrtc(par, chan->ddc_base) & 0x08) 79 val = 1; 80 81 return val; 82 } 83 84 static int nvidia_setup_i2c_bus(struct nvidia_i2c_chan *chan, const char *name, 85 unsigned int i2c_class) 86 { 87 int rc; 88 89 strscpy(chan->adapter.name, name, sizeof(chan->adapter.name)); 90 chan->adapter.owner = THIS_MODULE; 91 chan->adapter.class = i2c_class; 92 chan->adapter.algo_data = &chan->algo; 93 chan->adapter.dev.parent = &chan->par->pci_dev->dev; 94 chan->algo.setsda = nvidia_gpio_setsda; 95 chan->algo.setscl = nvidia_gpio_setscl; 96 chan->algo.getsda = nvidia_gpio_getsda; 97 chan->algo.getscl = nvidia_gpio_getscl; 98 chan->algo.udelay = 40; 99 chan->algo.timeout = msecs_to_jiffies(2); 100 chan->algo.data = chan; 101 102 i2c_set_adapdata(&chan->adapter, chan); 103 104 /* Raise SCL and SDA */ 105 nvidia_gpio_setsda(chan, 1); 106 nvidia_gpio_setscl(chan, 1); 107 udelay(20); 108 109 rc = i2c_bit_add_bus(&chan->adapter); 110 if (rc == 0) 111 dev_dbg(&chan->par->pci_dev->dev, 112 "I2C bus %s registered.\n", name); 113 else { 114 dev_warn(&chan->par->pci_dev->dev, 115 "Failed to register I2C bus %s.\n", name); 116 chan->par = NULL; 117 } 118 119 return rc; 120 } 121 122 void nvidia_create_i2c_busses(struct nvidia_par *par) 123 { 124 par->chan[0].par = par; 125 par->chan[1].par = par; 126 par->chan[2].par = par; 127 128 par->chan[0].ddc_base = (par->reverse_i2c) ? 0x36 : 0x3e; 129 nvidia_setup_i2c_bus(&par->chan[0], "nvidia #0", 130 (par->reverse_i2c) ? I2C_CLASS_HWMON : 0); 131 132 par->chan[1].ddc_base = (par->reverse_i2c) ? 0x3e : 0x36; 133 nvidia_setup_i2c_bus(&par->chan[1], "nvidia #1", 134 (par->reverse_i2c) ? 0 : I2C_CLASS_HWMON); 135 136 par->chan[2].ddc_base = 0x50; 137 nvidia_setup_i2c_bus(&par->chan[2], "nvidia #2", 0); 138 } 139 140 void nvidia_delete_i2c_busses(struct nvidia_par *par) 141 { 142 int i; 143 144 for (i = 0; i < 3; i++) { 145 if (!par->chan[i].par) 146 continue; 147 i2c_del_adapter(&par->chan[i].adapter); 148 par->chan[i].par = NULL; 149 } 150 } 151 152 int nvidia_probe_i2c_connector(struct fb_info *info, int conn, u8 **out_edid) 153 { 154 struct nvidia_par *par = info->par; 155 u8 *edid = NULL; 156 157 if (par->chan[conn - 1].par) 158 edid = fb_ddc_read(&par->chan[conn - 1].adapter); 159 160 if (!edid && conn == 1) { 161 /* try to get from firmware */ 162 const u8 *e = fb_firmware_edid(info->device); 163 164 if (e != NULL) 165 edid = kmemdup(e, EDID_LENGTH, GFP_KERNEL); 166 } 167 168 *out_edid = edid; 169 170 return (edid) ? 0 : 1; 171 } 172