drivers/i2c/busses/i2c-hydra.c

   1 /*
   2     i2c-hydra.c - Part of lm_sensors,  Linux kernel modules
   3                   for hardware monitoring
   4
   5     i2c Support for the Apple `Hydra' Mac I/O
   6
   7     Copyright (c) 1999-2004 Geert Uytterhoeven <geert@linux-m68k.org>
   8
   9     Based on i2c Support for Via Technologies 82C586B South Bridge
  10     Copyright (c) 1998, 1999 Kyösti Mälkki <kmalkki@cc.hut.fi>
  11
  12     This program is free software; you can redistribute it and/or modify
  13     it under the terms of the GNU General Public License as published by
  14     the Free Software Foundation; either version 2 of the License, or
  15     (at your option) any later version.
  16
  17     This program is distributed in the hope that it will be useful,
  18     but WITHOUT ANY WARRANTY; without even the implied warranty of
  19     MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  20     GNU General Public License for more details.
  21
  22     You should have received a copy of the GNU General Public License
  23     along with this program; if not, write to the Free Software
  24     Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
  25 */
  26
  27 #include <linux/kernel.h>
  28 #include <linux/module.h>
  29 #include <linux/pci.h>
  30 #include <linux/types.h>
  31 #include <linux/i2c.h>
  32 #include <linux/i2c-algo-bit.h>
  33 #include <linux/init.h>
  34 #include <asm/io.h>
  35 #include <asm/hydra.h>
  36
  37
  38 #define HYDRA_CPD_PD0   0x00000001      /* CachePD lines */
  39 #define HYDRA_CPD_PD1   0x00000002
  40 #define HYDRA_CPD_PD2   0x00000004
  41 #define HYDRA_CPD_PD3   0x00000008
  42
  43 #define HYDRA_SCLK      HYDRA_CPD_PD0
  44 #define HYDRA_SDAT      HYDRA_CPD_PD1
  45 #define HYDRA_SCLK_OE   0x00000010
  46 #define HYDRA_SDAT_OE   0x00000020
  47
  48 static inline void pdregw(void *data, u32 val)
  49 {
  50         struct Hydra *hydra = (struct Hydra *)data;
  51         writel(val, &hydra->CachePD);
  52 }
  53
  54 static inline u32 pdregr(void *data)
  55 {
  56         struct Hydra *hydra = (struct Hydra *)data;
  57         return readl(&hydra->CachePD);
  58 }
  59
  60 static void hydra_bit_setscl(void *data, int state)
  61 {
  62         u32 val = pdregr(data);
  63         if (state)
  64                 val &= ~HYDRA_SCLK_OE;
  65         else {
  66                 val &= ~HYDRA_SCLK;
  67                 val |= HYDRA_SCLK_OE;
  68         }
  69         pdregw(data, val);
  70 }
  71
  72 static void hydra_bit_setsda(void *data, int state)
  73 {
  74         u32 val = pdregr(data);
  75         if (state)
  76                 val &= ~HYDRA_SDAT_OE;
  77         else {
  78                 val &= ~HYDRA_SDAT;
  79                 val |= HYDRA_SDAT_OE;
  80         }
  81         pdregw(data, val);
  82 }
  83
  84 static int hydra_bit_getscl(void *data)
  85 {
  86         return (pdregr(data) & HYDRA_SCLK) != 0;
  87 }
  88
  89 static int hydra_bit_getsda(void *data)
  90 {
  91         return (pdregr(data) & HYDRA_SDAT) != 0;
  92 }
  93
  94 /* ------------------------------------------------------------------------ */
  95
  96 static struct i2c_algo_bit_data hydra_bit_data = {
  97         .setsda         = hydra_bit_setsda,
  98         .setscl         = hydra_bit_setscl,
  99         .getsda         = hydra_bit_getsda,
 100         .getscl         = hydra_bit_getscl,
 101         .udelay         = 5,
 102         .mdelay         = 5,
 103         .timeout        = HZ
 104 };
 105
 106 static struct i2c_adapter hydra_adap = {
 107         .owner          = THIS_MODULE,
 108         .name           = "Hydra i2c",
 109         .id             = I2C_HW_B_HYDRA,
 110         .algo_data      = &hydra_bit_data,
 111 };
 112
 113 static struct pci_device_id hydra_ids[] = {
 114         { PCI_DEVICE(PCI_VENDOR_ID_APPLE, PCI_DEVICE_ID_APPLE_HYDRA) },
 115         { 0, }
 116 };
 117
 118 MODULE_DEVICE_TABLE (pci, hydra_ids);
 119
 120 static int __devinit hydra_probe(struct pci_dev *dev,
 121                                  const struct pci_device_id *id)
 122 {
 123         unsigned long base = pci_resource_start(dev, 0);
 124         int res;
 125
 126         if (!request_mem_region(base+offsetof(struct Hydra, CachePD), 4,
 127                                 hydra_adap.name))
 128                 return -EBUSY;
 129
 130         hydra_bit_data.data = ioremap(base, pci_resource_len(dev, 0));
 131         if (hydra_bit_data.data == NULL) {
 132                 release_mem_region(base+offsetof(struct Hydra, CachePD), 4);
 133                 return -ENODEV;
 134         }
 135
 136         pdregw(hydra_bit_data.data, 0);         /* clear SCLK_OE and SDAT_OE */
 137         hydra_adap.dev.parent = &dev->dev;
 138         res = i2c_bit_add_bus(&hydra_adap);
 139         if (res < 0) {
 140                 iounmap(hydra_bit_data.data);
 141                 release_mem_region(base+offsetof(struct Hydra, CachePD), 4);
 142                 return res;
 143         }
 144         return 0;
 145 }
 146
 147 static void __devexit hydra_remove(struct pci_dev *dev)
 148 {
 149         pdregw(hydra_bit_data.data, 0);         /* clear SCLK_OE and SDAT_OE */
 150         i2c_bit_del_bus(&hydra_adap);
 151         iounmap(hydra_bit_data.data);
 152         release_mem_region(pci_resource_start(dev, 0)+
 153                            offsetof(struct Hydra, CachePD), 4);
 154 }
 155
 156
 157 static struct pci_driver hydra_driver = {
 158         .name           = "hydra_smbus",
 159         .id_table       = hydra_ids,
 160         .probe          = hydra_probe,
 161         .remove         = __devexit_p(hydra_remove),
 162 };
 163
 164 static int __init i2c_hydra_init(void)
 165 {
 166         return pci_register_driver(&hydra_driver);
 167 }
 168
 169
 170 static void __exit i2c_hydra_exit(void)
 171 {
 172         pci_unregister_driver(&hydra_driver);
 173 }
 174
 175
 176
 177 MODULE_AUTHOR("Geert Uytterhoeven <geert@linux-m68k.org>");
 178 MODULE_DESCRIPTION("i2c for Apple Hydra Mac I/O");
 179 MODULE_LICENSE("GPL");
 180
 181 module_init(i2c_hydra_init);
 182 module_exit(i2c_hydra_exit);
 183