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 #include <linux/export.h> 29 #include <linux/i2c.h> 30 #include <linux/i2c-algo-bit.h> 31 #include <drm/drmP.h> 32 33 #include "mgag200_drv.h" 34 35 static int mga_i2c_read_gpio(struct mga_device *mdev) 36 { 37 WREG8(DAC_INDEX, MGA1064_GEN_IO_DATA); 38 return RREG8(DAC_DATA); 39 } 40 41 static void mga_i2c_set_gpio(struct mga_device *mdev, int mask, int val) 42 { 43 int tmp; 44 45 WREG8(DAC_INDEX, MGA1064_GEN_IO_CTL); 46 tmp = (RREG8(DAC_DATA) & mask) | val; 47 WREG_DAC(MGA1064_GEN_IO_CTL, tmp); 48 WREG_DAC(MGA1064_GEN_IO_DATA, 0); 49 } 50 51 static inline void mga_i2c_set(struct mga_device *mdev, int mask, int state) 52 { 53 if (state) 54 state = 0; 55 else 56 state = mask; 57 mga_i2c_set_gpio(mdev, ~mask, state); 58 } 59 60 static void mga_gpio_setsda(void *data, int state) 61 { 62 struct mga_i2c_chan *i2c = data; 63 struct mga_device *mdev = i2c->dev->dev_private; 64 mga_i2c_set(mdev, i2c->data, state); 65 } 66 67 static void mga_gpio_setscl(void *data, int state) 68 { 69 struct mga_i2c_chan *i2c = data; 70 struct mga_device *mdev = i2c->dev->dev_private; 71 mga_i2c_set(mdev, i2c->clock, state); 72 } 73 74 static int mga_gpio_getsda(void *data) 75 { 76 struct mga_i2c_chan *i2c = data; 77 struct mga_device *mdev = i2c->dev->dev_private; 78 return (mga_i2c_read_gpio(mdev) & i2c->data) ? 1 : 0; 79 } 80 81 static int mga_gpio_getscl(void *data) 82 { 83 struct mga_i2c_chan *i2c = data; 84 struct mga_device *mdev = i2c->dev->dev_private; 85 return (mga_i2c_read_gpio(mdev) & i2c->clock) ? 1 : 0; 86 } 87 88 struct mga_i2c_chan *mgag200_i2c_create(struct drm_device *dev) 89 { 90 struct mga_device *mdev = dev->dev_private; 91 struct mga_i2c_chan *i2c; 92 int ret; 93 int data, clock; 94 95 WREG_DAC(MGA1064_GEN_IO_CTL2, 1); 96 WREG_DAC(MGA1064_GEN_IO_DATA, 0xff); 97 WREG_DAC(MGA1064_GEN_IO_CTL, 0); 98 99 switch (mdev->type) { 100 case G200_SE_A: 101 case G200_SE_B: 102 case G200_EV: 103 case G200_WB: 104 data = 1; 105 clock = 2; 106 break; 107 case G200_EH: 108 case G200_ER: 109 data = 2; 110 clock = 1; 111 break; 112 default: 113 data = 2; 114 clock = 8; 115 break; 116 } 117 118 i2c = kzalloc(sizeof(struct mga_i2c_chan), GFP_KERNEL); 119 if (!i2c) 120 return NULL; 121 122 i2c->data = data; 123 i2c->clock = clock; 124 i2c->adapter.owner = THIS_MODULE; 125 i2c->adapter.class = I2C_CLASS_DDC; 126 i2c->adapter.dev.parent = &dev->pdev->dev; 127 i2c->dev = dev; 128 i2c_set_adapdata(&i2c->adapter, i2c); 129 snprintf(i2c->adapter.name, sizeof(i2c->adapter.name), "mga i2c"); 130 131 i2c->adapter.algo_data = &i2c->bit; 132 133 i2c->bit.udelay = 10; 134 i2c->bit.timeout = 2; 135 i2c->bit.data = i2c; 136 i2c->bit.setsda = mga_gpio_setsda; 137 i2c->bit.setscl = mga_gpio_setscl; 138 i2c->bit.getsda = mga_gpio_getsda; 139 i2c->bit.getscl = mga_gpio_getscl; 140 141 ret = i2c_bit_add_bus(&i2c->adapter); 142 if (ret) { 143 kfree(i2c); 144 i2c = NULL; 145 } 146 return i2c; 147 } 148 149 void mgag200_i2c_destroy(struct mga_i2c_chan *i2c) 150 { 151 if (!i2c) 152 return; 153 i2c_del_adapter(&i2c->adapter); 154 kfree(i2c); 155 } 156 157