2 * linux/drivers/video/nvidia/nvidia-i2c.c - nVidia i2c
4 * Copyright 2004 Antonino A. Daplas <adaplas @pol.net>
6 * Based on rivafb-i2c.c
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
13 #include <linux/module.h>
14 #include <linux/kernel.h>
15 #include <linux/delay.h>
16 #include <linux/pci.h>
27 static void nvidia_gpio_setscl(void *data, int state)
29 struct nvidia_i2c_chan *chan = data;
30 struct nvidia_par *par = chan->par;
33 val = NVReadCrtc(par, chan->ddc_base + 1) & 0xf0;
40 NVWriteCrtc(par, chan->ddc_base + 1, val | 0x01);
43 static void nvidia_gpio_setsda(void *data, int state)
45 struct nvidia_i2c_chan *chan = data;
46 struct nvidia_par *par = chan->par;
49 val = NVReadCrtc(par, chan->ddc_base + 1) & 0xf0;
56 NVWriteCrtc(par, chan->ddc_base + 1, val | 0x01);
59 static int nvidia_gpio_getscl(void *data)
61 struct nvidia_i2c_chan *chan = data;
62 struct nvidia_par *par = chan->par;
65 if (NVReadCrtc(par, chan->ddc_base) & 0x04)
71 static int nvidia_gpio_getsda(void *data)
73 struct nvidia_i2c_chan *chan = data;
74 struct nvidia_par *par = chan->par;
77 if (NVReadCrtc(par, chan->ddc_base) & 0x08)
83 static int nvidia_setup_i2c_bus(struct nvidia_i2c_chan *chan, const char *name,
84 unsigned int i2c_class)
88 strcpy(chan->adapter.name, name);
89 chan->adapter.owner = THIS_MODULE;
90 chan->adapter.class = i2c_class;
91 chan->adapter.algo_data = &chan->algo;
92 chan->adapter.dev.parent = &chan->par->pci_dev->dev;
93 chan->algo.setsda = nvidia_gpio_setsda;
94 chan->algo.setscl = nvidia_gpio_setscl;
95 chan->algo.getsda = nvidia_gpio_getsda;
96 chan->algo.getscl = nvidia_gpio_getscl;
97 chan->algo.udelay = 40;
98 chan->algo.timeout = msecs_to_jiffies(2);
99 chan->algo.data = chan;
101 i2c_set_adapdata(&chan->adapter, chan);
103 /* Raise SCL and SDA */
104 nvidia_gpio_setsda(chan, 1);
105 nvidia_gpio_setscl(chan, 1);
108 rc = i2c_bit_add_bus(&chan->adapter);
110 dev_dbg(&chan->par->pci_dev->dev,
111 "I2C bus %s registered.\n", name);
113 dev_warn(&chan->par->pci_dev->dev,
114 "Failed to register I2C bus %s.\n", name);
121 void nvidia_create_i2c_busses(struct nvidia_par *par)
123 par->chan[0].par = par;
124 par->chan[1].par = par;
125 par->chan[2].par = par;
127 par->chan[0].ddc_base = (par->reverse_i2c) ? 0x36 : 0x3e;
128 nvidia_setup_i2c_bus(&par->chan[0], "nvidia #0",
129 (par->reverse_i2c) ? I2C_CLASS_HWMON : 0);
131 par->chan[1].ddc_base = (par->reverse_i2c) ? 0x3e : 0x36;
132 nvidia_setup_i2c_bus(&par->chan[1], "nvidia #1",
133 (par->reverse_i2c) ? 0 : I2C_CLASS_HWMON);
135 par->chan[2].ddc_base = 0x50;
136 nvidia_setup_i2c_bus(&par->chan[2], "nvidia #2", 0);
139 void nvidia_delete_i2c_busses(struct nvidia_par *par)
143 for (i = 0; i < 3; i++) {
144 if (!par->chan[i].par)
146 i2c_del_adapter(&par->chan[i].adapter);
147 par->chan[i].par = NULL;
151 int nvidia_probe_i2c_connector(struct fb_info *info, int conn, u8 **out_edid)
153 struct nvidia_par *par = info->par;
156 if (par->chan[conn - 1].par)
157 edid = fb_ddc_read(&par->chan[conn - 1].adapter);
159 if (!edid && conn == 1) {
160 /* try to get from firmware */
161 const u8 *e = fb_firmware_edid(info->device);
164 edid = kmemdup(e, EDID_LENGTH, GFP_KERNEL);
169 return (edid) ? 0 : 1;