File-copy from v4.4.100

This is the result of 'cp' from a linux-stable tree with the 'v4.4.100'
tag checked out (commit 26d6298789e695c9f627ce49a7bbd2286405798a) on
git://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git

Please refer to that tree for all history prior to this point.

Change-Id: I8a9ee2aea93cd29c52c847d0ce33091a73ae6afe
diff --git a/drivers/i2c/busses/i2c-designware-platdrv.c b/drivers/i2c/busses/i2c-designware-platdrv.c
new file mode 100644
index 0000000..a2ae221
--- /dev/null
+++ b/drivers/i2c/busses/i2c-designware-platdrv.c
@@ -0,0 +1,371 @@
+/*
+ * 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/dmi.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 u32 i2c_dw_get_clk_rate_khz(struct dw_i2c_dev *dev)
+{
+	return clk_get_rate(dev->clk)/1000;
+}
+
+#ifdef CONFIG_ACPI
+/*
+ * The HCNT/LCNT information coming from ACPI should be the most accurate
+ * for given platform. However, some systems get it wrong. On such systems
+ * we get better results by calculating those based on the input clock.
+ */
+static const struct dmi_system_id dw_i2c_no_acpi_params[] = {
+	{
+		.ident = "Dell Inspiron 7348",
+		.matches = {
+			DMI_MATCH(DMI_SYS_VENDOR, "Dell Inc."),
+			DMI_MATCH(DMI_PRODUCT_NAME, "Inspiron 7348"),
+		},
+	},
+	{ }
+};
+
+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 (dmi_check_system(dw_i2c_no_acpi_params))
+		return;
+
+	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);
+
+	id = acpi_match_device(pdev->dev.driver->acpi_match_table, &pdev->dev);
+	if (id && id->driver_data)
+		dev->accessor_flags |= (u32)id->driver_data;
+
+	return 0;
+}
+
+static const struct acpi_device_id dw_i2c_acpi_match[] = {
+	{ "INT33C2", 0 },
+	{ "INT33C3", 0 },
+	{ "INT3432", 0 },
+	{ "INT3433", 0 },
+	{ "80860F41", 0 },
+	{ "808622C1", 0 },
+	{ "AMD0010", ACCESS_INTR_MASK },
+	{ }
+};
+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_plat_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);
+
+	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;
+	}
+
+	adap = &dev->adapter;
+	adap->owner = THIS_MODULE;
+	adap->class = I2C_CLASS_DEPRECATED;
+	ACPI_COMPANION_SET(&adap->dev, ACPI_COMPANION(&pdev->dev));
+	adap->dev.of_node = pdev->dev.of_node;
+
+	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);
+	}
+
+	r = i2c_dw_probe(dev);
+	if (r && !dev->pm_runtime_disabled)
+		pm_runtime_disable(&pdev->dev);
+
+	return r;
+}
+
+static int dw_i2c_plat_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_dont_use_autosuspend(&pdev->dev);
+	pm_runtime_put_sync(&pdev->dev);
+	if (!dev->pm_runtime_disabled)
+		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_SLEEP
+static int dw_i2c_plat_prepare(struct device *dev)
+{
+	return pm_runtime_suspended(dev);
+}
+
+static void dw_i2c_plat_complete(struct device *dev)
+{
+	if (dev->power.direct_complete)
+		pm_request_resume(dev);
+}
+#else
+#define dw_i2c_plat_prepare	NULL
+#define dw_i2c_plat_complete	NULL
+#endif
+
+#ifdef CONFIG_PM
+static int dw_i2c_plat_runtime_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_plat_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;
+}
+
+#ifdef CONFIG_PM_SLEEP
+static int dw_i2c_plat_suspend(struct device *dev)
+{
+	pm_runtime_resume(dev);
+	return dw_i2c_plat_runtime_suspend(dev);
+}
+#endif
+
+static const struct dev_pm_ops dw_i2c_dev_pm_ops = {
+	.prepare = dw_i2c_plat_prepare,
+	.complete = dw_i2c_plat_complete,
+	SET_SYSTEM_SLEEP_PM_OPS(dw_i2c_plat_suspend, dw_i2c_plat_resume)
+	SET_RUNTIME_PM_OPS(dw_i2c_plat_runtime_suspend,
+			   dw_i2c_plat_resume,
+			   NULL)
+};
+
+#define DW_I2C_DEV_PMOPS (&dw_i2c_dev_pm_ops)
+#else
+#define DW_I2C_DEV_PMOPS NULL
+#endif
+
+/* work with hotplug and coldplug */
+MODULE_ALIAS("platform:i2c_designware");
+
+static struct platform_driver dw_i2c_driver = {
+	.probe = dw_i2c_plat_probe,
+	.remove = dw_i2c_plat_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_PMOPS,
+	},
+};
+
+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");