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 "../w1.h" 38 #include "../w1_int.h" 39 40 MODULE_LICENSE("GPL"); 41 MODULE_AUTHOR("Evgeniy Polyakov <zbr@ioremap.net>"); 42 MODULE_DESCRIPTION("Driver for transport(Dallas 1-wire protocol) over VGA DDC(matrox gpio)."); 43 44 static struct pci_device_id matrox_w1_tbl[] = { 45 { PCI_DEVICE(PCI_VENDOR_ID_MATROX, PCI_DEVICE_ID_MATROX_G400) }, 46 { }, 47 }; 48 MODULE_DEVICE_TABLE(pci, matrox_w1_tbl); 49 50 static int matrox_w1_probe(struct pci_dev *, const struct pci_device_id *); 51 static void matrox_w1_remove(struct pci_dev *); 52 53 static struct pci_driver matrox_w1_pci_driver = { 54 .name = "matrox_w1", 55 .id_table = matrox_w1_tbl, 56 .probe = matrox_w1_probe, 57 .remove = matrox_w1_remove, 58 }; 59 60 /* 61 * Matrox G400 DDC registers. 62 */ 63 64 #define MATROX_G400_DDC_CLK (1<<4) 65 #define MATROX_G400_DDC_DATA (1<<1) 66 67 #define MATROX_BASE 0x3C00 68 #define MATROX_STATUS 0x1e14 69 70 #define MATROX_PORT_INDEX_OFFSET 0x00 71 #define MATROX_PORT_DATA_OFFSET 0x0A 72 73 #define MATROX_GET_CONTROL 0x2A 74 #define MATROX_GET_DATA 0x2B 75 #define MATROX_CURSOR_CTL 0x06 76 77 struct matrox_device 78 { 79 void __iomem *base_addr; 80 void __iomem *port_index; 81 void __iomem *port_data; 82 u8 data_mask; 83 84 unsigned long phys_addr; 85 void __iomem *virt_addr; 86 unsigned long found; 87 88 struct w1_bus_master *bus_master; 89 }; 90 91 static u8 matrox_w1_read_ddc_bit(void *); 92 static void matrox_w1_write_ddc_bit(void *, u8); 93 94 /* 95 * These functions read and write DDC Data bit. 96 * 97 * Using tristate pins, since i can't find any open-drain pin in whole motherboard. 98 * Unfortunately we can't connect to Intel's 82801xx IO controller 99 * since we don't know motherboard schema, which has pretty unused(may be not) GPIO. 100 * 101 * I've heard that PIIX also has open drain pin. 102 * 103 * Port mapping. 104 */ 105 static __inline__ u8 matrox_w1_read_reg(struct matrox_device *dev, u8 reg) 106 { 107 u8 ret; 108 109 writeb(reg, dev->port_index); 110 ret = readb(dev->port_data); 111 barrier(); 112 113 return ret; 114 } 115 116 static __inline__ void matrox_w1_write_reg(struct matrox_device *dev, u8 reg, u8 val) 117 { 118 writeb(reg, dev->port_index); 119 writeb(val, dev->port_data); 120 wmb(); 121 } 122 123 static void matrox_w1_write_ddc_bit(void *data, u8 bit) 124 { 125 u8 ret; 126 struct matrox_device *dev = data; 127 128 if (bit) 129 bit = 0; 130 else 131 bit = dev->data_mask; 132 133 ret = matrox_w1_read_reg(dev, MATROX_GET_CONTROL); 134 matrox_w1_write_reg(dev, MATROX_GET_CONTROL, ((ret & ~dev->data_mask) | bit)); 135 matrox_w1_write_reg(dev, MATROX_GET_DATA, 0x00); 136 } 137 138 static u8 matrox_w1_read_ddc_bit(void *data) 139 { 140 u8 ret; 141 struct matrox_device *dev = data; 142 143 ret = matrox_w1_read_reg(dev, MATROX_GET_DATA); 144 145 return ret; 146 } 147 148 static void matrox_w1_hw_init(struct matrox_device *dev) 149 { 150 matrox_w1_write_reg(dev, MATROX_GET_DATA, 0xFF); 151 matrox_w1_write_reg(dev, MATROX_GET_CONTROL, 0x00); 152 } 153 154 static int matrox_w1_probe(struct pci_dev *pdev, const struct pci_device_id *ent) 155 { 156 struct matrox_device *dev; 157 int err; 158 159 if (pdev->vendor != PCI_VENDOR_ID_MATROX || pdev->device != PCI_DEVICE_ID_MATROX_G400) 160 return -ENODEV; 161 162 dev = kzalloc(sizeof(struct matrox_device) + 163 sizeof(struct w1_bus_master), GFP_KERNEL); 164 if (!dev) { 165 dev_err(&pdev->dev, 166 "%s: Failed to create new matrox_device object.\n", 167 __func__); 168 return -ENOMEM; 169 } 170 171 172 dev->bus_master = (struct w1_bus_master *)(dev + 1); 173 174 /* 175 * True for G400, for some other we need resource 0, see drivers/video/matrox/matroxfb_base.c 176 */ 177 178 dev->phys_addr = pci_resource_start(pdev, 1); 179 180 dev->virt_addr = ioremap_nocache(dev->phys_addr, 16384); 181 if (!dev->virt_addr) { 182 dev_err(&pdev->dev, "%s: failed to ioremap(0x%lx, %d).\n", 183 __func__, dev->phys_addr, 16384); 184 err = -EIO; 185 goto err_out_free_device; 186 } 187 188 dev->base_addr = dev->virt_addr + MATROX_BASE; 189 dev->port_index = dev->base_addr + MATROX_PORT_INDEX_OFFSET; 190 dev->port_data = dev->base_addr + MATROX_PORT_DATA_OFFSET; 191 dev->data_mask = (MATROX_G400_DDC_DATA); 192 193 matrox_w1_hw_init(dev); 194 195 dev->bus_master->data = dev; 196 dev->bus_master->read_bit = &matrox_w1_read_ddc_bit; 197 dev->bus_master->write_bit = &matrox_w1_write_ddc_bit; 198 199 err = w1_add_master_device(dev->bus_master); 200 if (err) 201 goto err_out_free_device; 202 203 pci_set_drvdata(pdev, dev); 204 205 dev->found = 1; 206 207 dev_info(&pdev->dev, "Matrox G400 GPIO transport layer for 1-wire.\n"); 208 209 return 0; 210 211 err_out_free_device: 212 if (dev->virt_addr) 213 iounmap(dev->virt_addr); 214 kfree(dev); 215 216 return err; 217 } 218 219 static void matrox_w1_remove(struct pci_dev *pdev) 220 { 221 struct matrox_device *dev = pci_get_drvdata(pdev); 222 223 if (dev->found) { 224 w1_remove_master_device(dev->bus_master); 225 iounmap(dev->virt_addr); 226 } 227 kfree(dev); 228 } 229 module_pci_driver(matrox_w1_pci_driver); 230