--- /dev/null
+/*
+ * 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)
+ return irq;
+
+ 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 (has_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 (has_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");
Code Review / kvmfornfv.git / blobdiff