diff options
Diffstat (limited to 'drivers/i2c/busses/i2c-designware-platdrv.c')
| -rw-r--r-- | drivers/i2c/busses/i2c-designware-platdrv.c | 215 |
1 files changed, 215 insertions, 0 deletions
diff --git a/drivers/i2c/busses/i2c-designware-platdrv.c b/drivers/i2c/busses/i2c-designware-platdrv.c new file mode 100644 index 00000000000..2d3657ab125 --- /dev/null +++ b/drivers/i2c/busses/i2c-designware-platdrv.c @@ -0,0 +1,215 @@ +/* + * Synopsys DesignWare I2C adapter driver (master only). + * + * Based on the TI DAVINCI I2C adapter driver. + * + * Copyright (C) 2006 Texas Instruments. + * Copyright (C) 2007 MontaVista Software Inc. + * Copyright (C) 2009 Provigent Ltd. + * + * ---------------------------------------------------------------------------- + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License as published by + * the Free Software Foundation; either version 2 of the License, or + * (at your option) any later version. + * + * This program is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + * GNU General Public License for more details. + * + * You should have received a copy of the GNU General Public License + * along with this program; if not, write to the Free Software + * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA. + * ---------------------------------------------------------------------------- + * + */ +#include <linux/kernel.h> +#include <linux/module.h> +#include <linux/delay.h> +#include <linux/i2c.h> +#include <linux/clk.h> +#include <linux/errno.h> +#include <linux/sched.h> +#include <linux/err.h> +#include <linux/interrupt.h> +#include <linux/platform_device.h> +#include <linux/io.h> +#include <linux/slab.h> +#include "i2c-designware-core.h" + +static struct i2c_algorithm i2c_dw_algo = { + .master_xfer = i2c_dw_xfer, + .functionality = i2c_dw_func, +}; +static u32 i2c_dw_get_clk_rate_khz(struct dw_i2c_dev *dev) +{ + return clk_get_rate(dev->clk)/1000; +} + +static int __devinit dw_i2c_probe(struct platform_device *pdev) +{ + struct dw_i2c_dev *dev; + struct i2c_adapter *adap; + struct resource *mem, *ioarea; + int irq, r; + + /* NOTE: driver uses the static register mapping */ + mem = platform_get_resource(pdev, IORESOURCE_MEM, 0); + if (!mem) { + dev_err(&pdev->dev, "no mem resource?\n"); + return -EINVAL; + } + + irq = platform_get_irq(pdev, 0); + if (irq < 0) { + dev_err(&pdev->dev, "no irq resource?\n"); + return irq; /* -ENXIO */ + } + + ioarea = request_mem_region(mem->start, resource_size(mem), + pdev->name); + if (!ioarea) { + dev_err(&pdev->dev, "I2C region already claimed\n"); + return -EBUSY; + } + + dev = kzalloc(sizeof(struct dw_i2c_dev), GFP_KERNEL); + if (!dev) { + r = -ENOMEM; + goto err_release_region; + } + + init_completion(&dev->cmd_complete); + mutex_init(&dev->lock); + dev->dev = get_device(&pdev->dev); + dev->irq = irq; + platform_set_drvdata(pdev, dev); + + dev->clk = clk_get(&pdev->dev, NULL); + dev->get_clk_rate_khz = i2c_dw_get_clk_rate_khz; + + if (IS_ERR(dev->clk)) { + r = -ENODEV; + goto err_free_mem; + } + clk_enable(dev->clk); + + dev->functionality = + I2C_FUNC_I2C | + I2C_FUNC_10BIT_ADDR | + I2C_FUNC_SMBUS_BYTE | + I2C_FUNC_SMBUS_BYTE_DATA | + I2C_FUNC_SMBUS_WORD_DATA | + I2C_FUNC_SMBUS_I2C_BLOCK; + dev->master_cfg = DW_IC_CON_MASTER | DW_IC_CON_SLAVE_DISABLE | + DW_IC_CON_RESTART_EN | DW_IC_CON_SPEED_FAST; + + dev->base = ioremap(mem->start, resource_size(mem)); + if (dev->base == NULL) { + dev_err(&pdev->dev, "failure mapping io resources\n"); + r = -EBUSY; + goto err_unuse_clocks; + } + { + u32 param1 = i2c_dw_read_comp_param(dev); + + dev->tx_fifo_depth = ((param1 >> 16) & 0xff) + 1; + dev->rx_fifo_depth = ((param1 >> 8) & 0xff) + 1; + } + r = i2c_dw_init(dev); + if (r) + goto err_iounmap; + + i2c_dw_disable_int(dev); + r = request_irq(dev->irq, i2c_dw_isr, IRQF_DISABLED, pdev->name, dev); + if (r) { + dev_err(&pdev->dev, "failure requesting irq %i\n", dev->irq); + goto err_iounmap; + } + + adap = &dev->adapter; + i2c_set_adapdata(adap, dev); + adap->owner = THIS_MODULE; + adap->class = I2C_CLASS_HWMON; + strlcpy(adap->name, "Synopsys DesignWare I2C adapter", + sizeof(adap->name)); + adap->algo = &i2c_dw_algo; + adap->dev.parent = &pdev->dev; + + adap->nr = pdev->id; + r = i2c_add_numbered_adapter(adap); + if (r) { + dev_err(&pdev->dev, "failure adding adapter\n"); + goto err_free_irq; + } + + return 0; + +err_free_irq: + free_irq(dev->irq, dev); +err_iounmap: + iounmap(dev->base); +err_unuse_clocks: + clk_disable(dev->clk); + clk_put(dev->clk); + dev->clk = NULL; +err_free_mem: + platform_set_drvdata(pdev, NULL); + put_device(&pdev->dev); + kfree(dev); +err_release_region: + release_mem_region(mem->start, resource_size(mem)); + + return r; +} + +static int __devexit dw_i2c_remove(struct platform_device *pdev) +{ + struct dw_i2c_dev *dev = platform_get_drvdata(pdev); + struct resource *mem; + + platform_set_drvdata(pdev, NULL); + i2c_del_adapter(&dev->adapter); + put_device(&pdev->dev); + + clk_disable(dev->clk); + clk_put(dev->clk); + dev->clk = NULL; + + i2c_dw_disable(dev); + free_irq(dev->irq, dev); + kfree(dev); + + mem = platform_get_resource(pdev, IORESOURCE_MEM, 0); + release_mem_region(mem->start, resource_size(mem)); + return 0; +} + +/* work with hotplug and coldplug */ +MODULE_ALIAS("platform:i2c_designware"); + +static struct platform_driver dw_i2c_driver = { + .remove = __devexit_p(dw_i2c_remove), + .driver = { + .name = "i2c_designware", + .owner = THIS_MODULE, + }, +}; + +static int __init dw_i2c_init_driver(void) +{ + return platform_driver_probe(&dw_i2c_driver, dw_i2c_probe); +} +module_init(dw_i2c_init_driver); + +static void __exit dw_i2c_exit_driver(void) +{ + platform_driver_unregister(&dw_i2c_driver); +} +module_exit(dw_i2c_exit_driver); + +MODULE_AUTHOR("Baruch Siach <baruch@tkos.co.il>"); +MODULE_DESCRIPTION("Synopsys DesignWare I2C bus adapter"); +MODULE_LICENSE("GPL"); |