1 /* 2 * matrox_w1.c 3 * 4 * Copyright (c) 2004 Evgeniy Polyakov <zbr@ioremap.net> 5 * 6 * 7 * This program is free software; you can redistribute it and/or modify 8 * it under the terms of the GNU General Public License as published by 9 * the Free Software Foundation; either version 2 of the License, or 10 * (at your option) any later version. 11 * 12 * This program is distributed in the hope that it will be useful, 13 * but WITHOUT ANY WARRANTY; without even the implied warranty of 14 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the 15 * GNU General Public License for more details. 16 * 17 * You should have received a copy of the GNU General Public License 18 * along with this program; if not, write to the Free Software 19 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA 20 */ 21 22 #include <asm/types.h> 23 #include <linux/atomic.h> 24 #include <asm/io.h> 25 26 #include <linux/delay.h> 27 #include <linux/kernel.h> 28 #include <linux/module.h> 29 #include <linux/list.h> 30 #include <linux/interrupt.h> 31 #include <linux/spinlock.h> 32 #include <linux/timer.h> 33 #include <linux/slab.h> 34 #include <linux/pci_ids.h> 35 #include <linux/pci.h> 36 37 #include <linux/w1.h> 38 39 /* 40 * Matrox G400 DDC registers. 41 */ 42 43 #define MATROX_G400_DDC_CLK (1<<4) 44 #define MATROX_G400_DDC_DATA (1<<1) 45 46 #define MATROX_BASE 0x3C00 47 #define MATROX_STATUS 0x1e14 48 49 #define MATROX_PORT_INDEX_OFFSET 0x00 50 #define MATROX_PORT_DATA_OFFSET 0x0A 51 52 #define MATROX_GET_CONTROL 0x2A 53 #define MATROX_GET_DATA 0x2B 54 #define MATROX_CURSOR_CTL 0x06 55 56 struct matrox_device 57 { 58 void __iomem *base_addr; 59 void __iomem *port_index; 60 void __iomem *port_data; 61 u8 data_mask; 62 63 unsigned long phys_addr; 64 void __iomem *virt_addr; 65 unsigned long found; 66 67 struct w1_bus_master *bus_master; 68 }; 69 70 /* 71 * These functions read and write DDC Data bit. 72 * 73 * Using tristate pins, since i can't find any open-drain pin in whole motherboard. 74 * Unfortunately we can't connect to Intel's 82801xx IO controller 75 * since we don't know motherboard schema, which has pretty unused(may be not) GPIO. 76 * 77 * I've heard that PIIX also has open drain pin. 78 * 79 * Port mapping. 80 */ 81 static __inline__ u8 matrox_w1_read_reg(struct matrox_device *dev, u8 reg) 82 { 83 u8 ret; 84 85 writeb(reg, dev->port_index); 86 ret = readb(dev->port_data); 87 barrier(); 88 89 return ret; 90 } 91 92 static __inline__ void matrox_w1_write_reg(struct matrox_device *dev, u8 reg, u8 val) 93 { 94 writeb(reg, dev->port_index); 95 writeb(val, dev->port_data); 96 wmb(); 97 } 98 99 static void matrox_w1_write_ddc_bit(void *data, u8 bit) 100 { 101 u8 ret; 102 struct matrox_device *dev = data; 103 104 if (bit) 105 bit = 0; 106 else 107 bit = dev->data_mask; 108 109 ret = matrox_w1_read_reg(dev, MATROX_GET_CONTROL); 110 matrox_w1_write_reg(dev, MATROX_GET_CONTROL, ((ret & ~dev->data_mask) | bit)); 111 matrox_w1_write_reg(dev, MATROX_GET_DATA, 0x00); 112 } 113 114 static u8 matrox_w1_read_ddc_bit(void *data) 115 { 116 u8 ret; 117 struct matrox_device *dev = data; 118 119 ret = matrox_w1_read_reg(dev, MATROX_GET_DATA); 120 121 return ret; 122 } 123 124 static void matrox_w1_hw_init(struct matrox_device *dev) 125 { 126 matrox_w1_write_reg(dev, MATROX_GET_DATA, 0xFF); 127 matrox_w1_write_reg(dev, MATROX_GET_CONTROL, 0x00); 128 } 129 130 static int matrox_w1_probe(struct pci_dev *pdev, const struct pci_device_id *ent) 131 { 132 struct matrox_device *dev; 133 int err; 134 135 if (pdev->vendor != PCI_VENDOR_ID_MATROX || pdev->device != PCI_DEVICE_ID_MATROX_G400) 136 return -ENODEV; 137 138 dev = kzalloc(sizeof(struct matrox_device) + 139 sizeof(struct w1_bus_master), GFP_KERNEL); 140 if (!dev) { 141 dev_err(&pdev->dev, 142 "%s: Failed to create new matrox_device object.\n", 143 __func__); 144 return -ENOMEM; 145 } 146 147 148 dev->bus_master = (struct w1_bus_master *)(dev + 1); 149 150 /* 151 * True for G400, for some other we need resource 0, see drivers/video/matrox/matroxfb_base.c 152 */ 153 154 dev->phys_addr = pci_resource_start(pdev, 1); 155 156 dev->virt_addr = ioremap_nocache(dev->phys_addr, 16384); 157 if (!dev->virt_addr) { 158 dev_err(&pdev->dev, "%s: failed to ioremap(0x%lx, %d).\n", 159 __func__, dev->phys_addr, 16384); 160 err = -EIO; 161 goto err_out_free_device; 162 } 163 164 dev->base_addr = dev->virt_addr + MATROX_BASE; 165 dev->port_index = dev->base_addr + MATROX_PORT_INDEX_OFFSET; 166 dev->port_data = dev->base_addr + MATROX_PORT_DATA_OFFSET; 167 dev->data_mask = (MATROX_G400_DDC_DATA); 168 169 matrox_w1_hw_init(dev); 170 171 dev->bus_master->data = dev; 172 dev->bus_master->read_bit = &matrox_w1_read_ddc_bit; 173 dev->bus_master->write_bit = &matrox_w1_write_ddc_bit; 174 175 err = w1_add_master_device(dev->bus_master); 176 if (err) 177 goto err_out_free_device; 178 179 pci_set_drvdata(pdev, dev); 180 181 dev->found = 1; 182 183 dev_info(&pdev->dev, "Matrox G400 GPIO transport layer for 1-wire.\n"); 184 185 return 0; 186 187 err_out_free_device: 188 if (dev->virt_addr) 189 iounmap(dev->virt_addr); 190 kfree(dev); 191 192 return err; 193 } 194 195 static void matrox_w1_remove(struct pci_dev *pdev) 196 { 197 struct matrox_device *dev = pci_get_drvdata(pdev); 198 199 if (dev->found) { 200 w1_remove_master_device(dev->bus_master); 201 iounmap(dev->virt_addr); 202 } 203 kfree(dev); 204 } 205 206 static struct pci_device_id matrox_w1_tbl[] = { 207 { PCI_DEVICE(PCI_VENDOR_ID_MATROX, PCI_DEVICE_ID_MATROX_G400) }, 208 { }, 209 }; 210 MODULE_DEVICE_TABLE(pci, matrox_w1_tbl); 211 212 static struct pci_driver matrox_w1_pci_driver = { 213 .name = "matrox_w1", 214 .id_table = matrox_w1_tbl, 215 .probe = matrox_w1_probe, 216 .remove = matrox_w1_remove, 217 }; 218 module_pci_driver(matrox_w1_pci_driver); 219 220 MODULE_AUTHOR("Evgeniy Polyakov <zbr@ioremap.net>"); 221 MODULE_DESCRIPTION("Driver for transport(Dallas 1-wire protocol) over VGA DDC(matrox gpio)."); 222 MODULE_LICENSE("GPL"); 223