| /* |
| * 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. |
| * ---------------------------------------------------------------------------- |
| * |
| */ |
| #include <linux/kernel.h> |
| #include <linux/module.h> |
| #include <linux/delay.h> |
| #include <linux/i2c.h> |
| #include <linux/clk.h> |
| #include <linux/clk-provider.h> |
| #include <linux/errno.h> |
| #include <linux/sched.h> |
| #include <linux/err.h> |
| #include <linux/interrupt.h> |
| #include <linux/of.h> |
| #include <linux/platform_device.h> |
| #include <linux/pm.h> |
| #include <linux/pm_runtime.h> |
| #include <linux/io.h> |
| #include <linux/slab.h> |
| #include <linux/acpi.h> |
| #include <linux/platform_data/i2c-designware.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; |
| } |
| |
| #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); |
| const struct acpi_device_id *id; |
| |
| 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, NULL); |
| dw_i2c_acpi_params(pdev, "FMCN", &dev->fs_hcnt, &dev->fs_lcnt, |
| &dev->sda_hold_time); |
| |
| /* |
| * Provide a way for Designware I2C host controllers that are not |
| * based on Intel LPSS to specify their input clock frequency via |
| * id->driver_data. |
| */ |
| id = acpi_match_device(pdev->dev.driver->acpi_match_table, &pdev->dev); |
| if (id && id->driver_data) |
| clk_register_fixed_rate(&pdev->dev, dev_name(&pdev->dev), NULL, |
| CLK_IS_ROOT, id->driver_data); |
| |
| return 0; |
| } |
| |
| static void dw_i2c_acpi_unconfigure(struct platform_device *pdev) |
| { |
| struct dw_i2c_dev *dev = platform_get_drvdata(pdev); |
| const struct acpi_device_id *id; |
| |
| id = acpi_match_device(pdev->dev.driver->acpi_match_table, &pdev->dev); |
| if (id && id->driver_data) |
| clk_unregister(dev->clk); |
| } |
| |
| static const struct acpi_device_id dw_i2c_acpi_match[] = { |
| { "INT33C2", 0 }, |
| { "INT33C3", 0 }, |
| { "INT3432", 0 }, |
| { "INT3433", 0 }, |
| { "80860F41", 0 }, |
| { "808622C1", 0 }, |
| { "AMD0010", 133 * 1000 * 1000 }, |
| { } |
| }; |
| MODULE_DEVICE_TABLE(acpi, dw_i2c_acpi_match); |
| #else |
| static inline int dw_i2c_acpi_configure(struct platform_device *pdev) |
| { |
| return -ENODEV; |
| } |
| static inline void dw_i2c_acpi_unconfigure(struct platform_device *pdev) { } |
| #endif |
| |
| static int dw_i2c_probe(struct platform_device *pdev) |
| { |
| struct dw_i2c_dev *dev; |
| struct i2c_adapter *adap; |
| struct resource *mem; |
| struct dw_i2c_platform_data *pdata; |
| int irq, r; |
| u32 clk_freq, ht = 0; |
| |
| 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); |
| |
| /* fast mode by default because of legacy reasons */ |
| clk_freq = 400000; |
| |
| if (ACPI_COMPANION(&pdev->dev)) { |
| dw_i2c_acpi_configure(pdev); |
| } else if (pdev->dev.of_node) { |
| of_property_read_u32(pdev->dev.of_node, |
| "i2c-sda-hold-time-ns", &ht); |
| |
| 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; |
| } |
| } else { |
| pdata = dev_get_platdata(&pdev->dev); |
| if (pdata) |
| clk_freq = pdata->i2c_scl_freq; |
| } |
| |
| r = i2c_dw_eval_lock_support(dev); |
| if (r) |
| return r; |
| |
| 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; |
| |
| 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); |
| |
| if (!dev->sda_hold_time && ht) { |
| u32 ic_clk = dev->get_clk_rate_khz(dev); |
| |
| dev->sda_hold_time = div_u64((u64)ic_clk * ht + 500000, |
| 1000000); |
| } |
| |
| if (!dev->tx_fifo_depth) { |
| 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; |
| } |
| |
| if (dev->pm_runtime_disabled) { |
| pm_runtime_forbid(&pdev->dev); |
| } else { |
| 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); |
| |
| if (ACPI_COMPANION(&pdev->dev)) |
| dw_i2c_acpi_unconfigure(pdev); |
| |
| 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); |
| |
| if (!i_dev->pm_runtime_disabled) |
| 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", |
| .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 <baruch@tkos.co.il>"); |
| MODULE_DESCRIPTION("Synopsys DesignWare I2C bus adapter"); |
| MODULE_LICENSE("GPL"); |