Jan Safrata | 5a52b1f | 2014-09-26 10:40:29 +0200 | [diff] [blame] | 1 | /* |
| 2 | * Copyright (c) 2002-2010, Intel Corporation. |
| 3 | * Copyright (c) 2014 ATRON electronic GmbH |
| 4 | * Author: Jan Safrata <jan.nikitenko@gmail.com> |
| 5 | * |
| 6 | * Permission is hereby granted, free of charge, to any person obtaining a copy |
| 7 | * of this software and associated documentation files (the "Software"), to deal |
| 8 | * in the Software without restriction, including without limitation the rights |
| 9 | * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell |
| 10 | * copies of the Software, and to permit persons to whom the Software is |
| 11 | * furnished to do so, subject to the following conditions: |
| 12 | * |
| 13 | * The above copyright notice and this permission notice shall be included in |
| 14 | * all copies or substantial portions of the Software. |
| 15 | * |
| 16 | * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR |
| 17 | * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, |
| 18 | * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE |
| 19 | * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER |
| 20 | * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, |
| 21 | * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN |
| 22 | * THE SOFTWARE. |
| 23 | * |
| 24 | */ |
| 25 | |
| 26 | #include <linux/kernel.h> |
| 27 | #include <linux/module.h> |
| 28 | #include <linux/pci.h> |
| 29 | #include <linux/types.h> |
| 30 | #include <linux/i2c.h> |
| 31 | #include <linux/i2c-algo-bit.h> |
| 32 | #include <linux/init.h> |
| 33 | #include <linux/io.h> |
| 34 | #include <linux/delay.h> |
| 35 | |
| 36 | #include <drm/drmP.h> |
| 37 | #include "psb_drv.h" |
| 38 | #include "psb_intel_reg.h" |
| 39 | |
| 40 | |
| 41 | /* |
| 42 | * LPC GPIO based I2C bus for LVDS of Atom E6xx |
| 43 | */ |
| 44 | |
| 45 | /*----------------------------------------------------------------------------- |
| 46 | * LPC Register Offsets. Used for LVDS GPIO Bit Bashing. Registers are part |
| 47 | * Atom E6xx [D31:F0] |
| 48 | ----------------------------------------------------------------------------*/ |
| 49 | #define RGEN 0x20 |
| 50 | #define RGIO 0x24 |
| 51 | #define RGLVL 0x28 |
| 52 | #define RGTPE 0x2C |
| 53 | #define RGTNE 0x30 |
| 54 | #define RGGPE 0x34 |
| 55 | #define RGSMI 0x38 |
| 56 | #define RGTS 0x3C |
| 57 | |
| 58 | /* The LVDS GPIO clock lines are GPIOSUS[3] |
| 59 | * The LVDS GPIO data lines are GPIOSUS[4] |
| 60 | */ |
| 61 | #define GPIO_CLOCK 0x08 |
| 62 | #define GPIO_DATA 0x10 |
| 63 | |
| 64 | #define LPC_READ_REG(chan, r) inl((chan)->reg + (r)) |
| 65 | #define LPC_WRITE_REG(chan, r, val) outl((val), (chan)->reg + (r)) |
| 66 | |
| 67 | static int get_clock(void *data) |
| 68 | { |
| 69 | struct psb_intel_i2c_chan *chan = data; |
| 70 | u32 val, tmp; |
| 71 | |
| 72 | val = LPC_READ_REG(chan, RGIO); |
| 73 | val |= GPIO_CLOCK; |
| 74 | LPC_WRITE_REG(chan, RGIO, val); |
| 75 | tmp = LPC_READ_REG(chan, RGLVL); |
| 76 | val = (LPC_READ_REG(chan, RGLVL) & GPIO_CLOCK) ? 1 : 0; |
| 77 | |
| 78 | return val; |
| 79 | } |
| 80 | |
| 81 | static int get_data(void *data) |
| 82 | { |
| 83 | struct psb_intel_i2c_chan *chan = data; |
| 84 | u32 val, tmp; |
| 85 | |
| 86 | val = LPC_READ_REG(chan, RGIO); |
| 87 | val |= GPIO_DATA; |
| 88 | LPC_WRITE_REG(chan, RGIO, val); |
| 89 | tmp = LPC_READ_REG(chan, RGLVL); |
| 90 | val = (LPC_READ_REG(chan, RGLVL) & GPIO_DATA) ? 1 : 0; |
| 91 | |
| 92 | return val; |
| 93 | } |
| 94 | |
| 95 | static void set_clock(void *data, int state_high) |
| 96 | { |
| 97 | struct psb_intel_i2c_chan *chan = data; |
| 98 | u32 val; |
| 99 | |
| 100 | if (state_high) { |
| 101 | val = LPC_READ_REG(chan, RGIO); |
| 102 | val |= GPIO_CLOCK; |
| 103 | LPC_WRITE_REG(chan, RGIO, val); |
| 104 | } else { |
| 105 | val = LPC_READ_REG(chan, RGIO); |
| 106 | val &= ~GPIO_CLOCK; |
| 107 | LPC_WRITE_REG(chan, RGIO, val); |
| 108 | val = LPC_READ_REG(chan, RGLVL); |
| 109 | val &= ~GPIO_CLOCK; |
| 110 | LPC_WRITE_REG(chan, RGLVL, val); |
| 111 | } |
| 112 | } |
| 113 | |
| 114 | static void set_data(void *data, int state_high) |
| 115 | { |
| 116 | struct psb_intel_i2c_chan *chan = data; |
| 117 | u32 val; |
| 118 | |
| 119 | if (state_high) { |
| 120 | val = LPC_READ_REG(chan, RGIO); |
| 121 | val |= GPIO_DATA; |
| 122 | LPC_WRITE_REG(chan, RGIO, val); |
| 123 | } else { |
| 124 | val = LPC_READ_REG(chan, RGIO); |
| 125 | val &= ~GPIO_DATA; |
| 126 | LPC_WRITE_REG(chan, RGIO, val); |
| 127 | val = LPC_READ_REG(chan, RGLVL); |
| 128 | val &= ~GPIO_DATA; |
| 129 | LPC_WRITE_REG(chan, RGLVL, val); |
| 130 | } |
| 131 | } |
| 132 | |
| 133 | void oaktrail_lvds_i2c_init(struct drm_encoder *encoder) |
| 134 | { |
| 135 | struct drm_device *dev = encoder->dev; |
| 136 | struct gma_encoder *gma_encoder = to_gma_encoder(encoder); |
| 137 | struct drm_psb_private *dev_priv = dev->dev_private; |
| 138 | struct psb_intel_i2c_chan *chan; |
| 139 | |
| 140 | chan = kzalloc(sizeof(struct psb_intel_i2c_chan), GFP_KERNEL); |
| 141 | if (!chan) |
| 142 | return; |
| 143 | |
| 144 | chan->drm_dev = dev; |
| 145 | chan->reg = dev_priv->lpc_gpio_base; |
| 146 | strncpy(chan->adapter.name, "gma500 LPC", I2C_NAME_SIZE - 1); |
| 147 | chan->adapter.owner = THIS_MODULE; |
| 148 | chan->adapter.algo_data = &chan->algo; |
| 149 | chan->adapter.dev.parent = &dev->pdev->dev; |
| 150 | chan->algo.setsda = set_data; |
| 151 | chan->algo.setscl = set_clock; |
| 152 | chan->algo.getsda = get_data; |
| 153 | chan->algo.getscl = get_clock; |
| 154 | chan->algo.udelay = 100; |
| 155 | chan->algo.timeout = usecs_to_jiffies(2200); |
| 156 | chan->algo.data = chan; |
| 157 | |
| 158 | i2c_set_adapdata(&chan->adapter, chan); |
| 159 | |
| 160 | set_data(chan, 1); |
| 161 | set_clock(chan, 1); |
| 162 | udelay(50); |
| 163 | |
| 164 | if (i2c_bit_add_bus(&chan->adapter)) { |
| 165 | kfree(chan); |
| 166 | return; |
| 167 | } |
| 168 | |
| 169 | gma_encoder->ddc_bus = chan; |
| 170 | } |