root/drivers/gpu/drm/mgag200/mgag200_i2c.c

DEFINITIONS

1. mga_i2c_read_gpio
2. mga_i2c_set_gpio
3. mga_i2c_set
4. mga_gpio_setsda
5. mga_gpio_setscl
6. mga_gpio_getsda
7. mga_gpio_getscl
8. mgag200_i2c_create
9. mgag200_i2c_destroy

   1 /*
   2  * Copyright 2012 Red Hat Inc.
   3  *
   4  * Permission is hereby granted, free of charge, to any person obtaining a
   5  * copy of this software and associated documentation files (the
   6  * "Software"), to deal in the Software without restriction, including
   7  * without limitation the rights to use, copy, modify, merge, publish,
   8  * distribute, sub license, and/or sell copies of the Software, and to
   9  * permit persons to whom the Software is furnished to do so, subject to
  10  * the following conditions:
  11  *
  12  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
  13  * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
  14  * FITNESS FOR A PARTICULAR PURPOSE AND NON-INFRINGEMENT. IN NO EVENT SHALL
  15  * THE COPYRIGHT HOLDERS, AUTHORS AND/OR ITS SUPPLIERS BE LIABLE FOR ANY CLAIM,
  16  * DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR
  17  * OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE
  18  * USE OR OTHER DEALINGS IN THE SOFTWARE.
  19  *
  20  * The above copyright notice and this permission notice (including the
  21  * next paragraph) shall be included in all copies or substantial portions
  22  * of the Software.
  23  *
  24  */
  25 /*
  26  * Authors: Dave Airlie <airlied@redhat.com>
  27  */
  28 
  29 #include <linux/export.h>
  30 #include <linux/i2c-algo-bit.h>
  31 #include <linux/i2c.h>
  32 
  33 #include <drm/drm_pci.h>
  34 
  35 #include "mgag200_drv.h"
  36 
  37 static int mga_i2c_read_gpio(struct mga_device *mdev)
  38 {
  39         WREG8(DAC_INDEX, MGA1064_GEN_IO_DATA);
  40         return RREG8(DAC_DATA);
  41 }
  42 
  43 static void mga_i2c_set_gpio(struct mga_device *mdev, int mask, int val)
  44 {
  45         int tmp;
  46 
  47         WREG8(DAC_INDEX, MGA1064_GEN_IO_CTL);
  48         tmp = (RREG8(DAC_DATA) & mask) | val;
  49         WREG_DAC(MGA1064_GEN_IO_CTL, tmp);
  50         WREG_DAC(MGA1064_GEN_IO_DATA, 0);
  51 }
  52 
  53 static inline void mga_i2c_set(struct mga_device *mdev, int mask, int state)
  54 {
  55         if (state)
  56                 state = 0;
  57         else
  58                 state = mask;
  59         mga_i2c_set_gpio(mdev, ~mask, state);
  60 }
  61 
  62 static void mga_gpio_setsda(void *data, int state)
  63 {
  64         struct mga_i2c_chan *i2c = data;
  65         struct mga_device *mdev = i2c->dev->dev_private;
  66         mga_i2c_set(mdev, i2c->data, state);
  67 }
  68 
  69 static void mga_gpio_setscl(void *data, int state)
  70 {
  71         struct mga_i2c_chan *i2c = data;
  72         struct mga_device *mdev = i2c->dev->dev_private;
  73         mga_i2c_set(mdev, i2c->clock, state);
  74 }
  75 
  76 static int mga_gpio_getsda(void *data)
  77 {
  78         struct mga_i2c_chan *i2c = data;
  79         struct mga_device *mdev = i2c->dev->dev_private;
  80         return (mga_i2c_read_gpio(mdev) & i2c->data) ? 1 : 0;
  81 }
  82 
  83 static int mga_gpio_getscl(void *data)
  84 {
  85         struct mga_i2c_chan *i2c = data;
  86         struct mga_device *mdev = i2c->dev->dev_private;
  87         return (mga_i2c_read_gpio(mdev) & i2c->clock) ? 1 : 0;
  88 }
  89 
  90 struct mga_i2c_chan *mgag200_i2c_create(struct drm_device *dev)
  91 {
  92         struct mga_device *mdev = dev->dev_private;
  93         struct mga_i2c_chan *i2c;
  94         int ret;
  95         int data, clock;
  96 
  97         WREG_DAC(MGA1064_GEN_IO_CTL2, 1);
  98         WREG_DAC(MGA1064_GEN_IO_DATA, 0xff);
  99         WREG_DAC(MGA1064_GEN_IO_CTL, 0);
 100 
 101         switch (mdev->type) {
 102         case G200_SE_A:
 103         case G200_SE_B:
 104         case G200_EV:
 105         case G200_WB:
 106         case G200_EW3:
 107                 data = 1;
 108                 clock = 2;
 109                 break;
 110         case G200_EH:
 111         case G200_EH3:
 112         case G200_ER:
 113                 data = 2;
 114                 clock = 1;
 115                 break;
 116         default:
 117                 data = 2;
 118                 clock = 8;
 119                 break;
 120         }
 121 
 122         i2c = kzalloc(sizeof(struct mga_i2c_chan), GFP_KERNEL);
 123         if (!i2c)
 124                 return NULL;
 125 
 126         i2c->data = data;
 127         i2c->clock = clock;
 128         i2c->adapter.owner = THIS_MODULE;
 129         i2c->adapter.class = I2C_CLASS_DDC;
 130         i2c->adapter.dev.parent = &dev->pdev->dev;
 131         i2c->dev = dev;
 132         i2c_set_adapdata(&i2c->adapter, i2c);
 133         snprintf(i2c->adapter.name, sizeof(i2c->adapter.name), "mga i2c");
 134 
 135         i2c->adapter.algo_data = &i2c->bit;
 136 
 137         i2c->bit.udelay = 10;
 138         i2c->bit.timeout = 2;
 139         i2c->bit.data = i2c;
 140         i2c->bit.setsda         = mga_gpio_setsda;
 141         i2c->bit.setscl         = mga_gpio_setscl;
 142         i2c->bit.getsda         = mga_gpio_getsda;
 143         i2c->bit.getscl         = mga_gpio_getscl;
 144 
 145         ret = i2c_bit_add_bus(&i2c->adapter);
 146         if (ret) {
 147                 kfree(i2c);
 148                 i2c = NULL;
 149         }
 150         return i2c;
 151 }
 152 
 153 void mgag200_i2c_destroy(struct mga_i2c_chan *i2c)
 154 {
 155         if (!i2c)
 156                 return;
 157         i2c_del_adapter(&i2c->adapter);
 158         kfree(i2c);
 159 }
 160