/* * 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 #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #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; } #ifdef CONFIG_ACPI static void dw_i2c_acpi_params(struct platform_device *pdev, char method[], u16 *hcnt, u16 *lcnt, u32 *sda_hold) { struct acpi_buffer buf = { ACPI_ALLOCATE_BUFFER }; acpi_handle handle = ACPI_HANDLE(&pdev->dev); union acpi_object *obj; if (ACPI_FAILURE(acpi_evaluate_object(handle, method, NULL, &buf))) return; obj = (union acpi_object *)buf.pointer; if (obj->type == ACPI_TYPE_PACKAGE && obj->package.count == 3) { const union acpi_object *objs = obj->package.elements; *hcnt = (u16)objs[0].integer.value; *lcnt = (u16)objs[1].integer.value; if (sda_hold) *sda_hold = (u32)objs[2].integer.value; } kfree(buf.pointer); } static int dw_i2c_acpi_configure(struct platform_device *pdev) { struct dw_i2c_dev *dev = platform_get_drvdata(pdev); bool fs_mode = dev->master_cfg & DW_IC_CON_SPEED_FAST; if (!ACPI_HANDLE(&pdev->dev)) return -ENODEV; dev->adapter.nr = -1; dev->tx_fifo_depth = 32; dev->rx_fifo_depth = 32; /* * Try to get SDA hold time and *CNT values from an ACPI method if * it exists for both supported speed modes. */ dw_i2c_acpi_params(pdev, "SSCN", &dev->ss_hcnt, &dev->ss_lcnt, fs_mode ? NULL : &dev->sda_hold_time); dw_i2c_acpi_params(pdev, "FMCN", &dev->fs_hcnt, &dev->fs_lcnt, fs_mode ? &dev->sda_hold_time : NULL); return 0; } static const struct acpi_device_id dw_i2c_acpi_match[] = { { "INT33C2", 0 }, { "INT33C3", 0 }, { "INT3432", 0 }, { "INT3433", 0 }, { "80860F41", 0 }, { "808622C1", 0 }, { } }; MODULE_DEVICE_TABLE(acpi, dw_i2c_acpi_match); #else static inline int dw_i2c_acpi_configure(struct platform_device *pdev) { return -ENODEV; } #endif static int dw_i2c_probe(struct platform_device *pdev) { struct dw_i2c_dev *dev; struct i2c_adapter *adap; struct resource *mem; int irq, r; u32 clk_freq; irq = platform_get_irq(pdev, 0); if (irq < 0) { dev_err(&pdev->dev, "no irq resource?\n"); return irq; /* -ENXIO */ } dev = devm_kzalloc(&pdev->dev, sizeof(struct dw_i2c_dev), GFP_KERNEL); if (!dev) return -ENOMEM; mem = platform_get_resource(pdev, IORESOURCE_MEM, 0); dev->base = devm_ioremap_resource(&pdev->dev, mem); if (IS_ERR(dev->base)) return PTR_ERR(dev->base); init_completion(&dev->cmd_complete); mutex_init(&dev->lock); dev->dev = &pdev->dev; dev->irq = irq; platform_set_drvdata(pdev, dev); dev->clk = devm_clk_get(&pdev->dev, NULL); dev->get_clk_rate_khz = i2c_dw_get_clk_rate_khz; if (IS_ERR(dev->clk)) return PTR_ERR(dev->clk); clk_prepare_enable(dev->clk); /* fast mode by default because of legacy reasons */ clk_freq = 400000; if (pdev->dev.of_node) { u32 ht = 0; u32 ic_clk = dev->get_clk_rate_khz(dev); of_property_read_u32(pdev->dev.of_node, "i2c-sda-hold-time-ns", &ht); dev->sda_hold_time = div_u64((u64)ic_clk * ht + 500000, 1000000); of_property_read_u32(pdev->dev.of_node, "i2c-sda-falling-time-ns", &dev->sda_falling_time); of_property_read_u32(pdev->dev.of_node, "i2c-scl-falling-time-ns", &dev->scl_falling_time); of_property_read_u32(pdev->dev.of_node, "clock-frequency", &clk_freq); /* Only standard mode at 100kHz and fast mode at 400kHz * are supported. */ if (clk_freq != 100000 && clk_freq != 400000) { dev_err(&pdev->dev, "Only 100kHz and 400kHz supported"); return -EINVAL; } } 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; if (clk_freq == 100000) dev->master_cfg = DW_IC_CON_MASTER | DW_IC_CON_SLAVE_DISABLE | DW_IC_CON_RESTART_EN | DW_IC_CON_SPEED_STD; else dev->master_cfg = DW_IC_CON_MASTER | DW_IC_CON_SLAVE_DISABLE | DW_IC_CON_RESTART_EN | DW_IC_CON_SPEED_FAST; /* Try first if we can configure the device from ACPI */ r = dw_i2c_acpi_configure(pdev); if (r) { u32 param1 = i2c_dw_read_comp_param(dev); dev->tx_fifo_depth = ((param1 >> 16) & 0xff) + 1; dev->rx_fifo_depth = ((param1 >> 8) & 0xff) + 1; dev->adapter.nr = pdev->id; } r = i2c_dw_init(dev); if (r) return r; i2c_dw_disable_int(dev); r = devm_request_irq(&pdev->dev, dev->irq, i2c_dw_isr, IRQF_SHARED, pdev->name, dev); if (r) { dev_err(&pdev->dev, "failure requesting irq %i\n", dev->irq); return r; } adap = &dev->adapter; i2c_set_adapdata(adap, dev); adap->owner = THIS_MODULE; adap->class = I2C_CLASS_DEPRECATED; strlcpy(adap->name, "Synopsys DesignWare I2C adapter", sizeof(adap->name)); adap->algo = &i2c_dw_algo; adap->dev.parent = &pdev->dev; adap->dev.of_node = pdev->dev.of_node; r = i2c_add_numbered_adapter(adap); if (r) { dev_err(&pdev->dev, "failure adding adapter\n"); return r; } pm_runtime_set_autosuspend_delay(&pdev->dev, 1000); pm_runtime_use_autosuspend(&pdev->dev); pm_runtime_set_active(&pdev->dev); pm_runtime_enable(&pdev->dev); return 0; } static int dw_i2c_remove(struct platform_device *pdev) { struct dw_i2c_dev *dev = platform_get_drvdata(pdev); pm_runtime_get_sync(&pdev->dev); i2c_del_adapter(&dev->adapter); i2c_dw_disable(dev); pm_runtime_put(&pdev->dev); pm_runtime_disable(&pdev->dev); return 0; } #ifdef CONFIG_OF static const struct of_device_id dw_i2c_of_match[] = { { .compatible = "snps,designware-i2c", }, {}, }; MODULE_DEVICE_TABLE(of, dw_i2c_of_match); #endif #ifdef CONFIG_PM static int dw_i2c_suspend(struct device *dev) { struct platform_device *pdev = to_platform_device(dev); struct dw_i2c_dev *i_dev = platform_get_drvdata(pdev); i2c_dw_disable(i_dev); clk_disable_unprepare(i_dev->clk); return 0; } static int dw_i2c_resume(struct device *dev) { struct platform_device *pdev = to_platform_device(dev); struct dw_i2c_dev *i_dev = platform_get_drvdata(pdev); clk_prepare_enable(i_dev->clk); i2c_dw_init(i_dev); return 0; } #endif static UNIVERSAL_DEV_PM_OPS(dw_i2c_dev_pm_ops, dw_i2c_suspend, dw_i2c_resume, NULL); /* work with hotplug and coldplug */ MODULE_ALIAS("platform:i2c_designware"); static struct platform_driver dw_i2c_driver = { .probe = dw_i2c_probe, .remove = dw_i2c_remove, .driver = { .name = "i2c_designware", .owner = THIS_MODULE, .of_match_table = of_match_ptr(dw_i2c_of_match), .acpi_match_table = ACPI_PTR(dw_i2c_acpi_match), .pm = &dw_i2c_dev_pm_ops, }, }; static int __init dw_i2c_init_driver(void) { return platform_driver_register(&dw_i2c_driver); } subsys_initcall(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 "); MODULE_DESCRIPTION("Synopsys DesignWare I2C bus adapter"); MODULE_LICENSE("GPL");