Dirk Brandewie | 2373f6b | 2011-10-29 10:57:23 +0100 | [diff] [blame] | 1 | /* |
| 2 | * Synopsys DesignWare I2C adapter driver (master only). |
| 3 | * |
| 4 | * Based on the TI DAVINCI I2C adapter driver. |
| 5 | * |
| 6 | * Copyright (C) 2006 Texas Instruments. |
| 7 | * Copyright (C) 2007 MontaVista Software Inc. |
| 8 | * Copyright (C) 2009 Provigent Ltd. |
| 9 | * |
| 10 | * ---------------------------------------------------------------------------- |
| 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 | */ |
| 28 | #include <linux/kernel.h> |
| 29 | #include <linux/module.h> |
| 30 | #include <linux/delay.h> |
| 31 | #include <linux/i2c.h> |
| 32 | #include <linux/clk.h> |
| 33 | #include <linux/errno.h> |
| 34 | #include <linux/sched.h> |
| 35 | #include <linux/err.h> |
| 36 | #include <linux/interrupt.h> |
| 37 | #include <linux/platform_device.h> |
| 38 | #include <linux/io.h> |
| 39 | #include <linux/slab.h> |
| 40 | #include "i2c-designware-core.h" |
| 41 | |
| 42 | static struct i2c_algorithm i2c_dw_algo = { |
| 43 | .master_xfer = i2c_dw_xfer, |
| 44 | .functionality = i2c_dw_func, |
| 45 | }; |
Dirk Brandewie | 1d31b58 | 2011-10-06 11:26:30 -0700 | [diff] [blame] | 46 | static u32 i2c_dw_get_clk_rate_khz(struct dw_i2c_dev *dev) |
| 47 | { |
| 48 | return clk_get_rate(dev->clk)/1000; |
| 49 | } |
Dirk Brandewie | 2373f6b | 2011-10-29 10:57:23 +0100 | [diff] [blame] | 50 | |
| 51 | static int __devinit dw_i2c_probe(struct platform_device *pdev) |
| 52 | { |
| 53 | struct dw_i2c_dev *dev; |
| 54 | struct i2c_adapter *adap; |
| 55 | struct resource *mem, *ioarea; |
| 56 | int irq, r; |
| 57 | |
| 58 | /* NOTE: driver uses the static register mapping */ |
| 59 | mem = platform_get_resource(pdev, IORESOURCE_MEM, 0); |
| 60 | if (!mem) { |
| 61 | dev_err(&pdev->dev, "no mem resource?\n"); |
| 62 | return -EINVAL; |
| 63 | } |
| 64 | |
| 65 | irq = platform_get_irq(pdev, 0); |
| 66 | if (irq < 0) { |
| 67 | dev_err(&pdev->dev, "no irq resource?\n"); |
| 68 | return irq; /* -ENXIO */ |
| 69 | } |
| 70 | |
| 71 | ioarea = request_mem_region(mem->start, resource_size(mem), |
| 72 | pdev->name); |
| 73 | if (!ioarea) { |
| 74 | dev_err(&pdev->dev, "I2C region already claimed\n"); |
| 75 | return -EBUSY; |
| 76 | } |
| 77 | |
| 78 | dev = kzalloc(sizeof(struct dw_i2c_dev), GFP_KERNEL); |
| 79 | if (!dev) { |
| 80 | r = -ENOMEM; |
| 81 | goto err_release_region; |
| 82 | } |
| 83 | |
| 84 | init_completion(&dev->cmd_complete); |
| 85 | mutex_init(&dev->lock); |
| 86 | dev->dev = get_device(&pdev->dev); |
| 87 | dev->irq = irq; |
| 88 | platform_set_drvdata(pdev, dev); |
| 89 | |
| 90 | dev->clk = clk_get(&pdev->dev, NULL); |
Dirk Brandewie | 1d31b58 | 2011-10-06 11:26:30 -0700 | [diff] [blame] | 91 | dev->get_clk_rate_khz = i2c_dw_get_clk_rate_khz; |
| 92 | |
Dirk Brandewie | 2373f6b | 2011-10-29 10:57:23 +0100 | [diff] [blame] | 93 | if (IS_ERR(dev->clk)) { |
| 94 | r = -ENODEV; |
| 95 | goto err_free_mem; |
| 96 | } |
| 97 | clk_enable(dev->clk); |
| 98 | |
Dirk Brandewie | 2fa8326 | 2011-10-06 11:26:31 -0700 | [diff] [blame] | 99 | dev->functionality = |
| 100 | I2C_FUNC_I2C | |
| 101 | I2C_FUNC_10BIT_ADDR | |
| 102 | I2C_FUNC_SMBUS_BYTE | |
| 103 | I2C_FUNC_SMBUS_BYTE_DATA | |
| 104 | I2C_FUNC_SMBUS_WORD_DATA | |
| 105 | I2C_FUNC_SMBUS_I2C_BLOCK; |
Dirk Brandewie | e18563f | 2011-10-06 11:26:32 -0700 | [diff] [blame^] | 106 | dev->master_cfg = DW_IC_CON_MASTER | DW_IC_CON_SLAVE_DISABLE | |
| 107 | DW_IC_CON_RESTART_EN | DW_IC_CON_SPEED_FAST; |
Dirk Brandewie | 2fa8326 | 2011-10-06 11:26:31 -0700 | [diff] [blame] | 108 | |
Dirk Brandewie | 2373f6b | 2011-10-29 10:57:23 +0100 | [diff] [blame] | 109 | dev->base = ioremap(mem->start, resource_size(mem)); |
| 110 | if (dev->base == NULL) { |
| 111 | dev_err(&pdev->dev, "failure mapping io resources\n"); |
| 112 | r = -EBUSY; |
| 113 | goto err_unuse_clocks; |
| 114 | } |
| 115 | { |
| 116 | u32 param1 = dw_readl(dev, DW_IC_COMP_PARAM_1); |
| 117 | |
| 118 | dev->tx_fifo_depth = ((param1 >> 16) & 0xff) + 1; |
| 119 | dev->rx_fifo_depth = ((param1 >> 8) & 0xff) + 1; |
| 120 | } |
| 121 | r = i2c_dw_init(dev); |
| 122 | if (r) |
| 123 | goto err_iounmap; |
| 124 | |
| 125 | dw_writel(dev, 0, DW_IC_INTR_MASK); /* disable IRQ */ |
| 126 | r = request_irq(dev->irq, i2c_dw_isr, IRQF_DISABLED, pdev->name, dev); |
| 127 | if (r) { |
| 128 | dev_err(&pdev->dev, "failure requesting irq %i\n", dev->irq); |
| 129 | goto err_iounmap; |
| 130 | } |
| 131 | |
| 132 | adap = &dev->adapter; |
| 133 | i2c_set_adapdata(adap, dev); |
| 134 | adap->owner = THIS_MODULE; |
| 135 | adap->class = I2C_CLASS_HWMON; |
| 136 | strlcpy(adap->name, "Synopsys DesignWare I2C adapter", |
| 137 | sizeof(adap->name)); |
| 138 | adap->algo = &i2c_dw_algo; |
| 139 | adap->dev.parent = &pdev->dev; |
| 140 | |
| 141 | adap->nr = pdev->id; |
| 142 | r = i2c_add_numbered_adapter(adap); |
| 143 | if (r) { |
| 144 | dev_err(&pdev->dev, "failure adding adapter\n"); |
| 145 | goto err_free_irq; |
| 146 | } |
| 147 | |
| 148 | return 0; |
| 149 | |
| 150 | err_free_irq: |
| 151 | free_irq(dev->irq, dev); |
| 152 | err_iounmap: |
| 153 | iounmap(dev->base); |
| 154 | err_unuse_clocks: |
| 155 | clk_disable(dev->clk); |
| 156 | clk_put(dev->clk); |
| 157 | dev->clk = NULL; |
| 158 | err_free_mem: |
| 159 | platform_set_drvdata(pdev, NULL); |
| 160 | put_device(&pdev->dev); |
| 161 | kfree(dev); |
| 162 | err_release_region: |
| 163 | release_mem_region(mem->start, resource_size(mem)); |
| 164 | |
| 165 | return r; |
| 166 | } |
| 167 | |
| 168 | static int __devexit dw_i2c_remove(struct platform_device *pdev) |
| 169 | { |
| 170 | struct dw_i2c_dev *dev = platform_get_drvdata(pdev); |
| 171 | struct resource *mem; |
| 172 | |
| 173 | platform_set_drvdata(pdev, NULL); |
| 174 | i2c_del_adapter(&dev->adapter); |
| 175 | put_device(&pdev->dev); |
| 176 | |
| 177 | clk_disable(dev->clk); |
| 178 | clk_put(dev->clk); |
| 179 | dev->clk = NULL; |
| 180 | |
| 181 | dw_writel(dev, 0, DW_IC_ENABLE); |
| 182 | free_irq(dev->irq, dev); |
| 183 | kfree(dev); |
| 184 | |
| 185 | mem = platform_get_resource(pdev, IORESOURCE_MEM, 0); |
| 186 | release_mem_region(mem->start, resource_size(mem)); |
| 187 | return 0; |
| 188 | } |
| 189 | |
| 190 | /* work with hotplug and coldplug */ |
| 191 | MODULE_ALIAS("platform:i2c_designware"); |
| 192 | |
| 193 | static struct platform_driver dw_i2c_driver = { |
| 194 | .remove = __devexit_p(dw_i2c_remove), |
| 195 | .driver = { |
| 196 | .name = "i2c_designware", |
| 197 | .owner = THIS_MODULE, |
| 198 | }, |
| 199 | }; |
| 200 | |
| 201 | static int __init dw_i2c_init_driver(void) |
| 202 | { |
| 203 | return platform_driver_probe(&dw_i2c_driver, dw_i2c_probe); |
| 204 | } |
| 205 | module_init(dw_i2c_init_driver); |
| 206 | |
| 207 | static void __exit dw_i2c_exit_driver(void) |
| 208 | { |
| 209 | platform_driver_unregister(&dw_i2c_driver); |
| 210 | } |
| 211 | module_exit(dw_i2c_exit_driver); |
| 212 | |
| 213 | MODULE_AUTHOR("Baruch Siach <baruch@tkos.co.il>"); |
| 214 | MODULE_DESCRIPTION("Synopsys DesignWare I2C bus adapter"); |
| 215 | MODULE_LICENSE("GPL"); |