drivers/w1/matrox_w1.c

   1 /*
   2  *      matrox_w1.c
   3  *
   4  * Copyright (c) 2004 Evgeniy Polyakov <johnpol@2ka.mipt.ru>
   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/atomic.h>
  23 #include <asm/types.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 #include <linux/timer.h>
  37
  38 #include "w1.h"
  39 #include "w1_int.h"
  40 #include "w1_log.h"
  41
  42 MODULE_LICENSE("GPL");
  43 MODULE_AUTHOR("Evgeniy Polyakov <johnpol@2ka.mipt.ru>");
  44 MODULE_DESCRIPTION("Driver for transport(Dallas 1-wire prtocol) over VGA DDC(matrox gpio).");
  45
  46 static struct pci_device_id matrox_w1_tbl[] = {
  47         { PCI_DEVICE(PCI_VENDOR_ID_MATROX, PCI_DEVICE_ID_MATROX_G400) },
  48         { },
  49 };
  50 MODULE_DEVICE_TABLE(pci, matrox_w1_tbl);
  51
  52 static int __devinit matrox_w1_probe(struct pci_dev *, const struct pci_device_id *);
  53 static void __devexit matrox_w1_remove(struct pci_dev *);
  54
  55 static struct pci_driver matrox_w1_pci_driver = {
  56         .name = "matrox_w1",
  57         .id_table = matrox_w1_tbl,
  58         .probe = matrox_w1_probe,
  59         .remove = __devexit_p(matrox_w1_remove),
  60 };
  61
  62 /*
  63  * Matrox G400 DDC registers.
  64  */
  65
  66 #define MATROX_G400_DDC_CLK             (1<<4)
  67 #define MATROX_G400_DDC_DATA            (1<<1)
  68
  69 #define MATROX_BASE                     0x3C00
  70 #define MATROX_STATUS                   0x1e14
  71
  72 #define MATROX_PORT_INDEX_OFFSET        0x00
  73 #define MATROX_PORT_DATA_OFFSET         0x0A
  74
  75 #define MATROX_GET_CONTROL              0x2A
  76 #define MATROX_GET_DATA                 0x2B
  77 #define MATROX_CURSOR_CTL               0x06
  78
  79 struct matrox_device
  80 {
  81         unsigned long base_addr;
  82         unsigned long port_index, port_data;
  83         u8 data_mask;
  84
  85         unsigned long phys_addr, virt_addr;
  86         unsigned long found;
  87
  88         struct w1_bus_master *bus_master;
  89 };
  90
  91 static u8 matrox_w1_read_ddc_bit(unsigned long);
  92 static void matrox_w1_write_ddc_bit(unsigned long, 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, wich 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(unsigned long data, u8 bit)
 124 {
 125         u8 ret;
 126         struct matrox_device *dev = (struct matrox_device *) 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(unsigned long data)
 139 {
 140         u8 ret;
 141         struct matrox_device *dev = (struct matrox_device *) 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 __devinit matrox_w1_probe(struct pci_dev *pdev, const struct pci_device_id *ent)
 155 {
 156         struct matrox_device *dev;
 157         int err;
 158
 159         assert(pdev != NULL);
 160         assert(ent != NULL);
 161
 162         if (pdev->vendor != PCI_VENDOR_ID_MATROX || pdev->device != PCI_DEVICE_ID_MATROX_G400)
 163                 return -ENODEV;
 164
 165         dev = kmalloc(sizeof(struct matrox_device) +
 166                        sizeof(struct w1_bus_master), GFP_KERNEL);
 167         if (!dev) {
 168                 dev_err(&pdev->dev,
 169                         "%s: Failed to create new matrox_device object.\n",
 170                         __func__);
 171                 return -ENOMEM;
 172         }
 173
 174         memset(dev, 0, sizeof(struct matrox_device) + sizeof(struct w1_bus_master));
 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 =
 185                 (unsigned long) ioremap_nocache(dev->phys_addr, 16384);
 186         if (!dev->virt_addr) {
 187                 dev_err(&pdev->dev, "%s: failed to ioremap(0x%lx, %d).\n",
 188                         __func__, dev->phys_addr, 16384);
 189                 err = -EIO;
 190                 goto err_out_free_device;
 191         }
 192
 193         dev->base_addr = dev->virt_addr + MATROX_BASE;
 194         dev->port_index = dev->base_addr + MATROX_PORT_INDEX_OFFSET;
 195         dev->port_data = dev->base_addr + MATROX_PORT_DATA_OFFSET;
 196         dev->data_mask = (MATROX_G400_DDC_DATA);
 197
 198         matrox_w1_hw_init(dev);
 199
 200         dev->bus_master->data = (unsigned long) dev;
 201         dev->bus_master->read_bit = &matrox_w1_read_ddc_bit;
 202         dev->bus_master->write_bit = &matrox_w1_write_ddc_bit;
 203
 204         err = w1_add_master_device(dev->bus_master);
 205         if (err)
 206                 goto err_out_free_device;
 207
 208         pci_set_drvdata(pdev, dev);
 209
 210         dev->found = 1;
 211
 212         dev_info(&pdev->dev, "Matrox G400 GPIO transport layer for 1-wire.\n");
 213
 214         return 0;
 215
 216 err_out_free_device:
 217         kfree(dev);
 218
 219         return err;
 220 }
 221
 222 static void __devexit matrox_w1_remove(struct pci_dev *pdev)
 223 {
 224         struct matrox_device *dev = pci_get_drvdata(pdev);
 225
 226         assert(dev != NULL);
 227
 228         if (dev->found) {
 229                 w1_remove_master_device(dev->bus_master);
 230                 iounmap((void *) dev->virt_addr);
 231         }
 232         kfree(dev);
 233 }
 234
 235 static int __init matrox_w1_init(void)
 236 {
 237         return pci_module_init(&matrox_w1_pci_driver);
 238 }
 239
 240 static void __exit matrox_w1_fini(void)
 241 {
 242         pci_unregister_driver(&matrox_w1_pci_driver);
 243 }
 244
 245 module_init(matrox_w1_init);
 246 module_exit(matrox_w1_fini);