drivers/bus/ti-sysc.c - third_party/kernel - Git at Google

 /*
  * ti-sysc.c - Texas Instruments sysc interconnect target driver
  *
  * This program is free software; you can redistribute it and/or modify
  * it under the terms of the GNU General Public License version 2 as
  * published by the Free Software Foundation.
  *
  * This program is distributed "as is" WITHOUT ANY WARRANTY of any
  * kind, whether express or implied; without even the implied warranty
  * of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  * GNU General Public License for more details.
  */

 #include <linux/io.h>
 #include <linux/clk.h>
 #include <linux/module.h>
 #include <linux/platform_device.h>
 #include <linux/pm_runtime.h>
 #include <linux/of_address.h>
 #include <linux/of_platform.h>

 enum sysc_registers {
 	SYSC_REVISION,
 	SYSC_SYSCONFIG,
 	SYSC_SYSSTATUS,
 	SYSC_MAX_REGS,
 };

 static const char * const reg_names[] = { "rev", "sysc", "syss", };

 enum sysc_clocks {
 	SYSC_FCK,
 	SYSC_ICK,
 	SYSC_MAX_CLOCKS,
 };

 static const char * const clock_names[] = { "fck", "ick", };

 /**
  * struct sysc - TI sysc interconnect target module registers and capabilities
  * @dev: struct device pointer
  * @module_pa: physical address of the interconnect target module
  * @module_size: size of the interconnect target module
  * @module_va: virtual address of the interconnect target module
  * @offsets: register offsets from module base
  * @clocks: clocks used by the interconnect target module
  * @legacy_mode: configured for legacy mode if set
  */
 struct sysc {
 	struct device *dev;
 	u64 module_pa;
 	u32 module_size;
 	void __iomem *module_va;
 	int offsets[SYSC_MAX_REGS];
 	struct clk *clocks[SYSC_MAX_CLOCKS];
 	const char *legacy_mode;
 };

 static u32 sysc_read_revision(struct sysc *ddata)
 {
 	return readl_relaxed(ddata->module_va +
 			     ddata->offsets[SYSC_REVISION]);
 }

 static int sysc_get_one_clock(struct sysc *ddata,
 			      enum sysc_clocks index)
 {
 	const char *name;
 	int error;

 	switch (index) {
 	case SYSC_FCK:
 		break;
 	case SYSC_ICK:
 		break;
 	default:
 		return -EINVAL;
 	}
 	name = clock_names[index];

 	ddata->clocks[index] = devm_clk_get(ddata->dev, name);
 	if (IS_ERR(ddata->clocks[index])) {
 		if (PTR_ERR(ddata->clocks[index]) == -ENOENT)
 			return 0;

 		dev_err(ddata->dev, "clock get error for %s: %li\n",
 			name, PTR_ERR(ddata->clocks[index]));

 		return PTR_ERR(ddata->clocks[index]);
 	}

 	error = clk_prepare(ddata->clocks[index]);
 	if (error) {
 		dev_err(ddata->dev, "clock prepare error for %s: %i\n",
 			name, error);

 		return error;
 	}

 	return 0;
 }

 static int sysc_get_clocks(struct sysc *ddata)
 {
 	int i, error;

 	if (ddata->legacy_mode)
 		return 0;

 	for (i = 0; i < SYSC_MAX_CLOCKS; i++) {
 		error = sysc_get_one_clock(ddata, i);
 		if (error && error != -ENOENT)
 			return error;
 	}

 	return 0;
 }

 /**
  * sysc_parse_and_check_child_range - parses module IO region from ranges
  * @ddata: device driver data
  *
  * In general we only need rev, syss, and sysc registers and not the whole
  * module range. But we do want the offsets for these registers from the
  * module base. This allows us to check them against the legacy hwmod
  * platform data. Let's also check the ranges are configured properly.
  */
 static int sysc_parse_and_check_child_range(struct sysc *ddata)
 {
 	struct device_node *np = ddata->dev->of_node;
 	const __be32 *ranges;
 	u32 nr_addr, nr_size;
 	int len, error;

 	ranges = of_get_property(np, "ranges", &len);
 	if (!ranges) {
 		dev_err(ddata->dev, "missing ranges for %pOF\n", np);

 		return -ENOENT;
 	}

 	len /= sizeof(*ranges);

 	if (len < 3) {
 		dev_err(ddata->dev, "incomplete ranges for %pOF\n", np);

 		return -EINVAL;
 	}

 	error = of_property_read_u32(np, "#address-cells", &nr_addr);
 	if (error)
 		return -ENOENT;

 	error = of_property_read_u32(np, "#size-cells", &nr_size);
 	if (error)
 		return -ENOENT;

 	if (nr_addr != 1 || nr_size != 1) {
 		dev_err(ddata->dev, "invalid ranges for %pOF\n", np);

 		return -EINVAL;
 	}

 	ranges++;
 	ddata->module_pa = of_translate_address(np, ranges++);
 	ddata->module_size = be32_to_cpup(ranges);

 	dev_dbg(ddata->dev, "interconnect target 0x%llx size 0x%x for %pOF\n",
 		ddata->module_pa, ddata->module_size, np);

 	return 0;
 }

 /**
  * sysc_check_one_child - check child configuration
  * @ddata: device driver data
  * @np: child device node
  *
  * Let's avoid messy situations where we have new interconnect target
  * node but children have "ti,hwmods". These belong to the interconnect
  * target node and are managed by this driver.
  */
 static int sysc_check_one_child(struct sysc *ddata,
 				struct device_node *np)
 {
 	const char *name;

 	name = of_get_property(np, "ti,hwmods", NULL);
 	if (name)
 		dev_warn(ddata->dev, "really a child ti,hwmods property?");

 	return 0;
 }

 static int sysc_check_children(struct sysc *ddata)
 {
 	struct device_node *child;
 	int error;

 	for_each_child_of_node(ddata->dev->of_node, child) {
 		error = sysc_check_one_child(ddata, child);
 		if (error)
 			return error;
 	}

 	return 0;
 }

 /**
  * sysc_parse_one - parses the interconnect target module registers
  * @ddata: device driver data
  * @reg: register to parse
  */
 static int sysc_parse_one(struct sysc *ddata, enum sysc_registers reg)
 {
 	struct resource *res;
 	const char *name;

 	switch (reg) {
 	case SYSC_REVISION:
 	case SYSC_SYSCONFIG:
 	case SYSC_SYSSTATUS:
 		name = reg_names[reg];
 		break;
 	default:
 		return -EINVAL;
 	}

 	res = platform_get_resource_byname(to_platform_device(ddata->dev),
 					   IORESOURCE_MEM, name);
 	if (!res) {
 		dev_dbg(ddata->dev, "has no %s register\n", name);
 		ddata->offsets[reg] = -ENODEV;

 		return 0;
 	}

 	ddata->offsets[reg] = res->start - ddata->module_pa;

 	return 0;
 }

 static int sysc_parse_registers(struct sysc *ddata)
 {
 	int i, error;

 	for (i = 0; i < SYSC_MAX_REGS; i++) {
 		error = sysc_parse_one(ddata, i);
 		if (error)
 			return error;
 	}

 	return 0;
 }

 /**
  * sysc_check_registers - check for misconfigured register overlaps
  * @ddata: device driver data
  */
 static int sysc_check_registers(struct sysc *ddata)
 {
 	int i, j, nr_regs = 0, nr_matches = 0;

 	for (i = 0; i < SYSC_MAX_REGS; i++) {
 		if (ddata->offsets[i] < 0)
 			continue;

 		if (ddata->offsets[i] > (ddata->module_size - 4)) {
 			dev_err(ddata->dev, "register outside module range");

 				return -EINVAL;
 		}

 		for (j = 0; j < SYSC_MAX_REGS; j++) {
 			if (ddata->offsets[j] < 0)
 				continue;

 			if (ddata->offsets[i] == ddata->offsets[j])
 				nr_matches++;
 		}
 		nr_regs++;
 	}

 	if (nr_regs < 1) {
 		dev_err(ddata->dev, "missing registers\n");

 		return -EINVAL;
 	}

 	if (nr_matches > nr_regs) {
 		dev_err(ddata->dev, "overlapping registers: (%i/%i)",
 			nr_regs, nr_matches);

 		return -EINVAL;
 	}

 	return 0;
 }

 /**
  * syc_ioremap - ioremap register space for the interconnect target module
  * @ddata: deviec driver data
  *
  * Note that the interconnect target module registers can be anywhere
  * within the first child device address space. For example, SGX has
  * them at offset 0x1fc00 in the 32MB module address space. We just
  * what we need around the interconnect target module registers.
  */
 static int sysc_ioremap(struct sysc *ddata)
 {
 	u32 size = 0;

 	if (ddata->offsets[SYSC_SYSSTATUS] >= 0)
 		size = ddata->offsets[SYSC_SYSSTATUS];
 	else if (ddata->offsets[SYSC_SYSCONFIG] >= 0)
 		size = ddata->offsets[SYSC_SYSCONFIG];
 	else if (ddata->offsets[SYSC_REVISION] >= 0)
 		size = ddata->offsets[SYSC_REVISION];
 	else
 		return -EINVAL;

 	size &= 0xfff00;
 	size += SZ_256;

 	ddata->module_va = devm_ioremap(ddata->dev,
 					ddata->module_pa,
 					size);
 	if (!ddata->module_va)
 		return -EIO;

 	return 0;
 }

 /**
  * sysc_map_and_check_registers - ioremap and check device registers
  * @ddata: device driver data
  */
 static int sysc_map_and_check_registers(struct sysc *ddata)
 {
 	int error;

 	error = sysc_parse_and_check_child_range(ddata);
 	if (error)
 		return error;

 	error = sysc_check_children(ddata);
 	if (error)
 		return error;

 	error = sysc_parse_registers(ddata);
 	if (error)
 		return error;

 	error = sysc_ioremap(ddata);
 	if (error)
 		return error;

 	error = sysc_check_registers(ddata);
 	if (error)
 		return error;

 	return 0;
 }

 /**
  * sysc_show_rev - read and show interconnect target module revision
  * @bufp: buffer to print the information to
  * @ddata: device driver data
  */
 static int sysc_show_rev(char *bufp, struct sysc *ddata)
 {
 	int error, len;

 	if (ddata->offsets[SYSC_REVISION] < 0)
 		return sprintf(bufp, ":NA");

 	error = pm_runtime_get_sync(ddata->dev);
 	if (error < 0) {
 		pm_runtime_put_noidle(ddata->dev);

 		return 0;
 	}

 	len = sprintf(bufp, ":%08x", sysc_read_revision(ddata));

 	pm_runtime_mark_last_busy(ddata->dev);
 	pm_runtime_put_autosuspend(ddata->dev);

 	return len;
 }

 static int sysc_show_reg(struct sysc *ddata,
 			 char *bufp, enum sysc_registers reg)
 {
 	if (ddata->offsets[reg] < 0)
 		return sprintf(bufp, ":NA");

 	return sprintf(bufp, ":%x", ddata->offsets[reg]);
 }

 /**
  * sysc_show_registers - show information about interconnect target module
  * @ddata: device driver data
  */
 static void sysc_show_registers(struct sysc *ddata)
 {
 	char buf[128];
 	char *bufp = buf;
 	int i;

 	for (i = 0; i < SYSC_MAX_REGS; i++)
 		bufp += sysc_show_reg(ddata, bufp, i);

 	bufp += sysc_show_rev(bufp, ddata);

 	dev_dbg(ddata->dev, "%llx:%x%s\n",
 		ddata->module_pa, ddata->module_size,
 		buf);
 }

 static int __maybe_unused sysc_runtime_suspend(struct device *dev)
 {
 	struct sysc *ddata;
 	int i;

 	ddata = dev_get_drvdata(dev);

 	if (ddata->legacy_mode)
 		return 0;

 	for (i = 0; i < SYSC_MAX_CLOCKS; i++) {
 		if (IS_ERR_OR_NULL(ddata->clocks[i]))
 			continue;
 		clk_disable(ddata->clocks[i]);
 	}

 	return 0;
 }

 static int __maybe_unused sysc_runtime_resume(struct device *dev)
 {
 	struct sysc *ddata;
 	int i, error;

 	ddata = dev_get_drvdata(dev);

 	if (ddata->legacy_mode)
 		return 0;

 	for (i = 0; i < SYSC_MAX_CLOCKS; i++) {
 		if (IS_ERR_OR_NULL(ddata->clocks[i]))
 			continue;
 		error = clk_enable(ddata->clocks[i]);
 		if (error)
 			return error;
 	}

 	return 0;
 }

 static const struct dev_pm_ops sysc_pm_ops = {
 	SET_RUNTIME_PM_OPS(sysc_runtime_suspend,
 			   sysc_runtime_resume,
 			   NULL)
 };

 static void sysc_unprepare(struct sysc *ddata)
 {
 	int i;

 	for (i = 0; i < SYSC_MAX_CLOCKS; i++) {
 		if (!IS_ERR_OR_NULL(ddata->clocks[i]))
 			clk_unprepare(ddata->clocks[i]);
 	}
 }

 static int sysc_probe(struct platform_device *pdev)
 {
 	struct device_node *np = pdev->dev.of_node;
 	struct sysc *ddata;
 	int error;

 	ddata = devm_kzalloc(&pdev->dev, sizeof(*ddata), GFP_KERNEL);
 	if (!ddata)
 		return -ENOMEM;

 	ddata->dev = &pdev->dev;
 	ddata->legacy_mode = of_get_property(np, "ti,hwmods", NULL);

 	error = sysc_get_clocks(ddata);
 	if (error)
 		return error;

 	error = sysc_map_and_check_registers(ddata);
 	if (error)
 		goto unprepare;

 	platform_set_drvdata(pdev, ddata);

 	pm_runtime_enable(ddata->dev);
 	error = pm_runtime_get_sync(ddata->dev);
 	if (error < 0) {
 		pm_runtime_put_noidle(ddata->dev);
 		pm_runtime_disable(ddata->dev);
 		goto unprepare;
 	}

 	pm_runtime_use_autosuspend(ddata->dev);

 	sysc_show_registers(ddata);

 	error = of_platform_populate(ddata->dev->of_node,
 				     NULL, NULL, ddata->dev);
 	if (error)
 		goto err;

 	pm_runtime_mark_last_busy(ddata->dev);
 	pm_runtime_put_autosuspend(ddata->dev);

 	return 0;

 err:
 	pm_runtime_dont_use_autosuspend(&pdev->dev);
 	pm_runtime_put_sync(&pdev->dev);
 	pm_runtime_disable(&pdev->dev);
 unprepare:
 	sysc_unprepare(ddata);

 	return error;
 }

 static int sysc_remove(struct platform_device *pdev)
 {
 	struct sysc *ddata = platform_get_drvdata(pdev);
 	int error;

 	error = pm_runtime_get_sync(ddata->dev);
 	if (error < 0) {
 		pm_runtime_put_noidle(ddata->dev);
 		pm_runtime_disable(ddata->dev);
 		goto unprepare;
 	}

 	of_platform_depopulate(&pdev->dev);

 	pm_runtime_dont_use_autosuspend(&pdev->dev);
 	pm_runtime_put_sync(&pdev->dev);
 	pm_runtime_disable(&pdev->dev);

 unprepare:
 	sysc_unprepare(ddata);

 	return 0;
 }

 static const struct of_device_id sysc_match[] = {
 	{ .compatible = "ti,sysc-omap2" },
 	{ .compatible = "ti,sysc-omap4" },
 	{ .compatible = "ti,sysc-omap4-simple" },
 	{ .compatible = "ti,sysc-omap3430-sr" },
 	{ .compatible = "ti,sysc-omap3630-sr" },
 	{ .compatible = "ti,sysc-omap4-sr" },
 	{ .compatible = "ti,sysc-omap3-sham" },
 	{ .compatible = "ti,sysc-omap-aes" },
 	{ .compatible = "ti,sysc-mcasp" },
 	{ .compatible = "ti,sysc-usb-host-fs" },
 	{  },
 };
 MODULE_DEVICE_TABLE(of, sysc_match);

 static struct platform_driver sysc_driver = {
 	.probe		= sysc_probe,
 	.remove		= sysc_remove,
 	.driver         = {
 		.name   = "ti-sysc",
 		.of_match_table	= sysc_match,
 		.pm = &sysc_pm_ops,
 	},
 };
 module_platform_driver(sysc_driver);

 MODULE_DESCRIPTION("TI sysc interconnect target driver");
 MODULE_LICENSE("GPL v2");
	/*
	* ti-sysc.c - Texas Instruments sysc interconnect target driver
	*
	* This program is free software; you can redistribute it and/or modify
	* it under the terms of the GNU General Public License version 2 as
	* published by the Free Software Foundation.
	*
	* This program is distributed "as is" WITHOUT ANY WARRANTY of any
	* kind, whether express or implied; without even the implied warranty
	* of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
	* GNU General Public License for more details.
	*/

	#include <linux/io.h>
	#include <linux/clk.h>
	#include <linux/module.h>
	#include <linux/platform_device.h>
	#include <linux/pm_runtime.h>
	#include <linux/of_address.h>
	#include <linux/of_platform.h>

	enum sysc_registers {
	SYSC_REVISION,
	SYSC_SYSCONFIG,
	SYSC_SYSSTATUS,
	SYSC_MAX_REGS,
	};

	static const char * const reg_names[] = { "rev", "sysc", "syss", };

	enum sysc_clocks {
	SYSC_FCK,
	SYSC_ICK,
	SYSC_MAX_CLOCKS,
	};

	static const char * const clock_names[] = { "fck", "ick", };

	/**
	* struct sysc - TI sysc interconnect target module registers and capabilities
	* @dev: struct device pointer
	* @module_pa: physical address of the interconnect target module
	* @module_size: size of the interconnect target module
	* @module_va: virtual address of the interconnect target module
	* @offsets: register offsets from module base
	* @clocks: clocks used by the interconnect target module
	* @legacy_mode: configured for legacy mode if set
	*/
	struct sysc {
	struct device *dev;
	u64 module_pa;
	u32 module_size;
	void __iomem *module_va;
	int offsets[SYSC_MAX_REGS];
	struct clk *clocks[SYSC_MAX_CLOCKS];
	const char *legacy_mode;
	};

	static u32 sysc_read_revision(struct sysc *ddata)
	{
	return readl_relaxed(ddata->module_va +
	ddata->offsets[SYSC_REVISION]);
	}

	static int sysc_get_one_clock(struct sysc *ddata,
	enum sysc_clocks index)
	{
	const char *name;
	int error;

	switch (index) {
	case SYSC_FCK:
	break;
	case SYSC_ICK:
	break;
	default:
	return -EINVAL;
	}
	name = clock_names[index];

	ddata->clocks[index] = devm_clk_get(ddata->dev, name);
	if (IS_ERR(ddata->clocks[index])) {
	if (PTR_ERR(ddata->clocks[index]) == -ENOENT)
	return 0;

	dev_err(ddata->dev, "clock get error for %s: %li\n",
	name, PTR_ERR(ddata->clocks[index]));

	return PTR_ERR(ddata->clocks[index]);
	}

	error = clk_prepare(ddata->clocks[index]);
	if (error) {
	dev_err(ddata->dev, "clock prepare error for %s: %i\n",
	name, error);

	return error;
	}

	return 0;
	}

	static int sysc_get_clocks(struct sysc *ddata)
	{
	int i, error;

	if (ddata->legacy_mode)
	return 0;

	for (i = 0; i < SYSC_MAX_CLOCKS; i++) {
	error = sysc_get_one_clock(ddata, i);
	if (error && error != -ENOENT)
	return error;
	}

	return 0;
	}

	/**
	* sysc_parse_and_check_child_range - parses module IO region from ranges
	* @ddata: device driver data
	*
	* In general we only need rev, syss, and sysc registers and not the whole
	* module range. But we do want the offsets for these registers from the
	* module base. This allows us to check them against the legacy hwmod
	* platform data. Let's also check the ranges are configured properly.
	*/
	static int sysc_parse_and_check_child_range(struct sysc *ddata)
	{
	struct device_node *np = ddata->dev->of_node;
	const __be32 *ranges;
	u32 nr_addr, nr_size;
	int len, error;

	ranges = of_get_property(np, "ranges", &len);
	if (!ranges) {
	dev_err(ddata->dev, "missing ranges for %pOF\n", np);

	return -ENOENT;
	}

	len /= sizeof(*ranges);

	if (len < 3) {
	dev_err(ddata->dev, "incomplete ranges for %pOF\n", np);

	return -EINVAL;
	}

	error = of_property_read_u32(np, "#address-cells", &nr_addr);
	if (error)
	return -ENOENT;

	error = of_property_read_u32(np, "#size-cells", &nr_size);
	if (error)
	return -ENOENT;

	if (nr_addr != 1 \|\| nr_size != 1) {
	dev_err(ddata->dev, "invalid ranges for %pOF\n", np);

	return -EINVAL;
	}

	ranges++;
	ddata->module_pa = of_translate_address(np, ranges++);
	ddata->module_size = be32_to_cpup(ranges);

	dev_dbg(ddata->dev, "interconnect target 0x%llx size 0x%x for %pOF\n",
	ddata->module_pa, ddata->module_size, np);

	return 0;
	}

	/**
	* sysc_check_one_child - check child configuration
	* @ddata: device driver data
	* @np: child device node
	*
	* Let's avoid messy situations where we have new interconnect target
	* node but children have "ti,hwmods". These belong to the interconnect
	* target node and are managed by this driver.
	*/
	static int sysc_check_one_child(struct sysc *ddata,
	struct device_node *np)
	{
	const char *name;

	name = of_get_property(np, "ti,hwmods", NULL);
	if (name)
	dev_warn(ddata->dev, "really a child ti,hwmods property?");

	return 0;
	}

	static int sysc_check_children(struct sysc *ddata)
	{
	struct device_node *child;
	int error;

	for_each_child_of_node(ddata->dev->of_node, child) {
	error = sysc_check_one_child(ddata, child);
	if (error)
	return error;
	}

	return 0;
	}

	/**
	* sysc_parse_one - parses the interconnect target module registers
	* @ddata: device driver data
	* @reg: register to parse
	*/
	static int sysc_parse_one(struct sysc *ddata, enum sysc_registers reg)
	{
	struct resource *res;
	const char *name;

	switch (reg) {
	case SYSC_REVISION:
	case SYSC_SYSCONFIG:
	case SYSC_SYSSTATUS:
	name = reg_names[reg];
	break;
	default:
	return -EINVAL;
	}

	res = platform_get_resource_byname(to_platform_device(ddata->dev),
	IORESOURCE_MEM, name);
	if (!res) {
	dev_dbg(ddata->dev, "has no %s register\n", name);
	ddata->offsets[reg] = -ENODEV;

	return 0;
	}

	ddata->offsets[reg] = res->start - ddata->module_pa;

	return 0;
	}

	static int sysc_parse_registers(struct sysc *ddata)
	{
	int i, error;

	for (i = 0; i < SYSC_MAX_REGS; i++) {
	error = sysc_parse_one(ddata, i);
	if (error)
	return error;
	}

	return 0;
	}

	/**
	* sysc_check_registers - check for misconfigured register overlaps
	* @ddata: device driver data
	*/
	static int sysc_check_registers(struct sysc *ddata)
	{
	int i, j, nr_regs = 0, nr_matches = 0;

	for (i = 0; i < SYSC_MAX_REGS; i++) {
	if (ddata->offsets[i] < 0)
	continue;

	if (ddata->offsets[i] > (ddata->module_size - 4)) {
	dev_err(ddata->dev, "register outside module range");

	return -EINVAL;
	}

	for (j = 0; j < SYSC_MAX_REGS; j++) {
	if (ddata->offsets[j] < 0)
	continue;

	if (ddata->offsets[i] == ddata->offsets[j])
	nr_matches++;
	}
	nr_regs++;
	}

	if (nr_regs < 1) {
	dev_err(ddata->dev, "missing registers\n");

	return -EINVAL;
	}

	if (nr_matches > nr_regs) {
	dev_err(ddata->dev, "overlapping registers: (%i/%i)",
	nr_regs, nr_matches);

	return -EINVAL;
	}

	return 0;
	}

	/**
	* syc_ioremap - ioremap register space for the interconnect target module
	* @ddata: deviec driver data
	*
	* Note that the interconnect target module registers can be anywhere
	* within the first child device address space. For example, SGX has
	* them at offset 0x1fc00 in the 32MB module address space. We just
	* what we need around the interconnect target module registers.
	*/
	static int sysc_ioremap(struct sysc *ddata)
	{
	u32 size = 0;

	if (ddata->offsets[SYSC_SYSSTATUS] >= 0)
	size = ddata->offsets[SYSC_SYSSTATUS];
	else if (ddata->offsets[SYSC_SYSCONFIG] >= 0)
	size = ddata->offsets[SYSC_SYSCONFIG];
	else if (ddata->offsets[SYSC_REVISION] >= 0)
	size = ddata->offsets[SYSC_REVISION];
	else
	return -EINVAL;

	size &= 0xfff00;
	size += SZ_256;

	ddata->module_va = devm_ioremap(ddata->dev,
	ddata->module_pa,
	size);
	if (!ddata->module_va)
	return -EIO;

	return 0;
	}

	/**
	* sysc_map_and_check_registers - ioremap and check device registers
	* @ddata: device driver data
	*/
	static int sysc_map_and_check_registers(struct sysc *ddata)
	{
	int error;

	error = sysc_parse_and_check_child_range(ddata);
	if (error)
	return error;

	error = sysc_check_children(ddata);
	if (error)
	return error;

	error = sysc_parse_registers(ddata);
	if (error)
	return error;

	error = sysc_ioremap(ddata);
	if (error)
	return error;

	error = sysc_check_registers(ddata);
	if (error)
	return error;

	return 0;
	}

	/**
	* sysc_show_rev - read and show interconnect target module revision
	* @bufp: buffer to print the information to
	* @ddata: device driver data
	*/
	static int sysc_show_rev(char bufp, struct sysc ddata)
	{
	int error, len;

	if (ddata->offsets[SYSC_REVISION] < 0)
	return sprintf(bufp, ":NA");

	error = pm_runtime_get_sync(ddata->dev);
	if (error < 0) {
	pm_runtime_put_noidle(ddata->dev);

	return 0;
	}

	len = sprintf(bufp, ":%08x", sysc_read_revision(ddata));

	pm_runtime_mark_last_busy(ddata->dev);
	pm_runtime_put_autosuspend(ddata->dev);

	return len;
	}

	static int sysc_show_reg(struct sysc *ddata,
	char *bufp, enum sysc_registers reg)
	{
	if (ddata->offsets[reg] < 0)
	return sprintf(bufp, ":NA");

	return sprintf(bufp, ":%x", ddata->offsets[reg]);
	}

	/**
	* sysc_show_registers - show information about interconnect target module
	* @ddata: device driver data
	*/
	static void sysc_show_registers(struct sysc *ddata)
	{
	char buf[128];
	char *bufp = buf;
	int i;

	for (i = 0; i < SYSC_MAX_REGS; i++)
	bufp += sysc_show_reg(ddata, bufp, i);

	bufp += sysc_show_rev(bufp, ddata);

	dev_dbg(ddata->dev, "%llx:%x%s\n",
	ddata->module_pa, ddata->module_size,
	buf);
	}

	static int __maybe_unused sysc_runtime_suspend(struct device *dev)
	{
	struct sysc *ddata;
	int i;

	ddata = dev_get_drvdata(dev);

	if (ddata->legacy_mode)
	return 0;

	for (i = 0; i < SYSC_MAX_CLOCKS; i++) {
	if (IS_ERR_OR_NULL(ddata->clocks[i]))
	continue;
	clk_disable(ddata->clocks[i]);
	}

	return 0;
	}

	static int __maybe_unused sysc_runtime_resume(struct device *dev)
	{
	struct sysc *ddata;
	int i, error;

	ddata = dev_get_drvdata(dev);

	if (ddata->legacy_mode)
	return 0;

	for (i = 0; i < SYSC_MAX_CLOCKS; i++) {
	if (IS_ERR_OR_NULL(ddata->clocks[i]))
	continue;
	error = clk_enable(ddata->clocks[i]);
	if (error)
	return error;
	}

	return 0;
	}

	static const struct dev_pm_ops sysc_pm_ops = {
	SET_RUNTIME_PM_OPS(sysc_runtime_suspend,
	sysc_runtime_resume,
	NULL)
	};

	static void sysc_unprepare(struct sysc *ddata)
	{
	int i;

	for (i = 0; i < SYSC_MAX_CLOCKS; i++) {
	if (!IS_ERR_OR_NULL(ddata->clocks[i]))
	clk_unprepare(ddata->clocks[i]);
	}
	}

	static int sysc_probe(struct platform_device *pdev)
	{
	struct device_node *np = pdev->dev.of_node;
	struct sysc *ddata;
	int error;

	ddata = devm_kzalloc(&pdev->dev, sizeof(*ddata), GFP_KERNEL);
	if (!ddata)
	return -ENOMEM;

	ddata->dev = &pdev->dev;
	ddata->legacy_mode = of_get_property(np, "ti,hwmods", NULL);

	error = sysc_get_clocks(ddata);
	if (error)
	return error;

	error = sysc_map_and_check_registers(ddata);
	if (error)
	goto unprepare;

	platform_set_drvdata(pdev, ddata);

	pm_runtime_enable(ddata->dev);
	error = pm_runtime_get_sync(ddata->dev);
	if (error < 0) {
	pm_runtime_put_noidle(ddata->dev);
	pm_runtime_disable(ddata->dev);
	goto unprepare;
	}

	pm_runtime_use_autosuspend(ddata->dev);

	sysc_show_registers(ddata);

	error = of_platform_populate(ddata->dev->of_node,
	NULL, NULL, ddata->dev);
	if (error)
	goto err;

	pm_runtime_mark_last_busy(ddata->dev);
	pm_runtime_put_autosuspend(ddata->dev);

	return 0;

	err:
	pm_runtime_dont_use_autosuspend(&pdev->dev);
	pm_runtime_put_sync(&pdev->dev);
	pm_runtime_disable(&pdev->dev);
	unprepare:
	sysc_unprepare(ddata);

	return error;
	}

	static int sysc_remove(struct platform_device *pdev)
	{
	struct sysc *ddata = platform_get_drvdata(pdev);
	int error;

	error = pm_runtime_get_sync(ddata->dev);
	if (error < 0) {
	pm_runtime_put_noidle(ddata->dev);
	pm_runtime_disable(ddata->dev);
	goto unprepare;
	}

	of_platform_depopulate(&pdev->dev);

	pm_runtime_dont_use_autosuspend(&pdev->dev);
	pm_runtime_put_sync(&pdev->dev);
	pm_runtime_disable(&pdev->dev);

	unprepare:
	sysc_unprepare(ddata);

	return 0;
	}

	static const struct of_device_id sysc_match[] = {
	{ .compatible = "ti,sysc-omap2" },
	{ .compatible = "ti,sysc-omap4" },
	{ .compatible = "ti,sysc-omap4-simple" },
	{ .compatible = "ti,sysc-omap3430-sr" },
	{ .compatible = "ti,sysc-omap3630-sr" },
	{ .compatible = "ti,sysc-omap4-sr" },
	{ .compatible = "ti,sysc-omap3-sham" },
	{ .compatible = "ti,sysc-omap-aes" },
	{ .compatible = "ti,sysc-mcasp" },
	{ .compatible = "ti,sysc-usb-host-fs" },
	{ },
	};
	MODULE_DEVICE_TABLE(of, sysc_match);

	static struct platform_driver sysc_driver = {
	.probe = sysc_probe,
	.remove = sysc_remove,
	.driver = {
	.name = "ti-sysc",
	.of_match_table = sysc_match,
	.pm = &sysc_pm_ops,
	},
	};
	module_platform_driver(sysc_driver);

	MODULE_DESCRIPTION("TI sysc interconnect target driver");
	MODULE_LICENSE("GPL v2");