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 #include "../w1_log.h" 40 41 MODULE_LICENSE("GPL"); 42 MODULE_AUTHOR("Evgeniy Polyakov <zbr@ioremap.net>"); 43 MODULE_DESCRIPTION("Driver for transport(Dallas 1-wire prtocol) over VGA DDC(matrox gpio)."); 44 45 static struct pci_device_id matrox_w1_tbl[] = { 46 { PCI_DEVICE(PCI_VENDOR_ID_MATROX, PCI_DEVICE_ID_MATROX_G400) }, 47 { }, 48 }; 49 MODULE_DEVICE_TABLE(pci, matrox_w1_tbl); 50 51 static int matrox_w1_probe(struct pci_dev *, const struct pci_device_id *); 52 static void matrox_w1_remove(struct pci_dev *); 53 54 static struct pci_driver matrox_w1_pci_driver = { 55 .name = "matrox_w1", 56 .id_table = matrox_w1_tbl, 57 .probe = matrox_w1_probe, 58 .remove = matrox_w1_remove, 59 }; 60 61 /* 62 * Matrox G400 DDC registers. 63 */ 64 65 #define MATROX_G400_DDC_CLK (1<<4) 66 #define MATROX_G400_DDC_DATA (1<<1) 67 68 #define MATROX_BASE 0x3C00 69 #define MATROX_STATUS 0x1e14 70 71 #define MATROX_PORT_INDEX_OFFSET 0x00 72 #define MATROX_PORT_DATA_OFFSET 0x0A 73 74 #define MATROX_GET_CONTROL 0x2A 75 #define MATROX_GET_DATA 0x2B 76 #define MATROX_CURSOR_CTL 0x06 77 78 struct matrox_device 79 { 80 void __iomem *base_addr; 81 void __iomem *port_index; 82 void __iomem *port_data; 83 u8 data_mask; 84 85 unsigned long phys_addr; 86 void __iomem *virt_addr; 87 unsigned long found; 88 89 struct w1_bus_master *bus_master; 90 }; 91 92 static u8 matrox_w1_read_ddc_bit(void *); 93 static void matrox_w1_write_ddc_bit(void *, u8); 94 95 /* 96 * These functions read and write DDC Data bit. 97 * 98 * Using tristate pins, since i can't find any open-drain pin in whole motherboard. 99 * Unfortunately we can't connect to Intel's 82801xx IO controller 100 * since we don't know motherboard schema, which has pretty unused(may be not) GPIO. 101 * 102 * I've heard that PIIX also has open drain pin. 103 * 104 * Port mapping. 105 */ 106 static __inline__ u8 matrox_w1_read_reg(struct matrox_device *dev, u8 reg) 107 { 108 u8 ret; 109 110 writeb(reg, dev->port_index); 111 ret = readb(dev->port_data); 112 barrier(); 113 114 return ret; 115 } 116 117 static __inline__ void matrox_w1_write_reg(struct matrox_device *dev, u8 reg, u8 val) 118 { 119 writeb(reg, dev->port_index); 120 writeb(val, dev->port_data); 121 wmb(); 122 } 123 124 static void matrox_w1_write_ddc_bit(void *data, u8 bit) 125 { 126 u8 ret; 127 struct matrox_device *dev = data; 128 129 if (bit) 130 bit = 0; 131 else 132 bit = dev->data_mask; 133 134 ret = matrox_w1_read_reg(dev, MATROX_GET_CONTROL); 135 matrox_w1_write_reg(dev, MATROX_GET_CONTROL, ((ret & ~dev->data_mask) | bit)); 136 matrox_w1_write_reg(dev, MATROX_GET_DATA, 0x00); 137 } 138 139 static u8 matrox_w1_read_ddc_bit(void *data) 140 { 141 u8 ret; 142 struct matrox_device *dev = data; 143 144 ret = matrox_w1_read_reg(dev, MATROX_GET_DATA); 145 146 return ret; 147 } 148 149 static void matrox_w1_hw_init(struct matrox_device *dev) 150 { 151 matrox_w1_write_reg(dev, MATROX_GET_DATA, 0xFF); 152 matrox_w1_write_reg(dev, MATROX_GET_CONTROL, 0x00); 153 } 154 155 static int matrox_w1_probe(struct pci_dev *pdev, const struct pci_device_id *ent) 156 { 157 struct matrox_device *dev; 158 int err; 159 160 assert(pdev != NULL); 161 assert(ent != NULL); 162 163 if (pdev->vendor != PCI_VENDOR_ID_MATROX || pdev->device != PCI_DEVICE_ID_MATROX_G400) 164 return -ENODEV; 165 166 dev = kzalloc(sizeof(struct matrox_device) + 167 sizeof(struct w1_bus_master), GFP_KERNEL); 168 if (!dev) { 169 dev_err(&pdev->dev, 170 "%s: Failed to create new matrox_device object.\n", 171 __func__); 172 return -ENOMEM; 173 } 174 175 176 dev->bus_master = (struct w1_bus_master *)(dev + 1); 177 178 /* 179 * True for G400, for some other we need resource 0, see drivers/video/matrox/matroxfb_base.c 180 */ 181 182 dev->phys_addr = pci_resource_start(pdev, 1); 183 184 dev->virt_addr = ioremap_nocache(dev->phys_addr, 16384); 185 if (!dev->virt_addr) { 186 dev_err(&pdev->dev, "%s: failed to ioremap(0x%lx, %d).\n", 187 __func__, dev->phys_addr, 16384); 188 err = -EIO; 189 goto err_out_free_device; 190 } 191 192 dev->base_addr = dev->virt_addr + MATROX_BASE; 193 dev->port_index = dev->base_addr + MATROX_PORT_INDEX_OFFSET; 194 dev->port_data = dev->base_addr + MATROX_PORT_DATA_OFFSET; 195 dev->data_mask = (MATROX_G400_DDC_DATA); 196 197 matrox_w1_hw_init(dev); 198 199 dev->bus_master->data = dev; 200 dev->bus_master->read_bit = &matrox_w1_read_ddc_bit; 201 dev->bus_master->write_bit = &matrox_w1_write_ddc_bit; 202 203 err = w1_add_master_device(dev->bus_master); 204 if (err) 205 goto err_out_free_device; 206 207 pci_set_drvdata(pdev, dev); 208 209 dev->found = 1; 210 211 dev_info(&pdev->dev, "Matrox G400 GPIO transport layer for 1-wire.\n"); 212 213 return 0; 214 215 err_out_free_device: 216 if (dev->virt_addr) 217 iounmap(dev->virt_addr); 218 kfree(dev); 219 220 return err; 221 } 222 223 static void matrox_w1_remove(struct pci_dev *pdev) 224 { 225 struct matrox_device *dev = pci_get_drvdata(pdev); 226 227 assert(dev != NULL); 228 229 if (dev->found) { 230 w1_remove_master_device(dev->bus_master); 231 iounmap(dev->virt_addr); 232 } 233 kfree(dev); 234 } 235 236 static int __init matrox_w1_init(void) 237 { 238 return pci_register_driver(&matrox_w1_pci_driver); 239 } 240 241 static void __exit matrox_w1_fini(void) 242 { 243 pci_unregister_driver(&matrox_w1_pci_driver); 244 } 245 246 module_init(matrox_w1_init); 247 module_exit(matrox_w1_fini); 248