// SPDX-License-Identifier: GPL-2.0/* * Copyright 2019 NXP */ #include <linux/clk.h>#include <linux/devfreq.h>#include <linux/device.h>#include <linux/module.h>#include <linux/of.h>#include <linux/pm_opp.h>#include <linux/platform_device.h>#include <linux/slab.h> struct imx_bus {	struct devfreq_dev_profile profile;	struct devfreq *devfreq;	struct clk *clk;	struct platform_device *icc_pdev;}; static int imx_bus_target(struct device *dev,		unsigned long *freq, u32 flags){	struct dev_pm_opp *new_opp;	int ret; 	new_opp = devfreq_recommended_opp(dev, freq, flags);	if (IS_ERR(new_opp)) {		ret = PTR_ERR(new_opp);		dev_err(dev, "failed to get recommended opp: %d\n", ret);		return ret;	}	dev_pm_opp_put(new_opp); 	return dev_pm_opp_set_rate(dev, *freq);} static int imx_bus_get_cur_freq(struct device *dev, unsigned long *freq){	struct imx_bus *priv = dev_get_drvdata(dev); 	*freq = clk_get_rate(priv->clk); 	return 0;} static void imx_bus_exit(struct device *dev){	struct imx_bus *priv = dev_get_drvdata(dev); 	dev_pm_opp_of_remove_table(dev);	platform_device_unregister(priv->icc_pdev);} /* imx_bus_init_icc() - register matching icc provider if required */static int imx_bus_init_icc(struct device *dev){	struct imx_bus *priv = dev_get_drvdata(dev);	const char *icc_driver_name; 	if (!of_property_present(dev->of_node, "#interconnect-cells"))		return 0;	if (!IS_ENABLED(CONFIG_INTERCONNECT_IMX)) {		dev_warn(dev, "imx interconnect drivers disabled\n");		return 0;	} 	icc_driver_name = of_device_get_match_data(dev);	if (!icc_driver_name) {		dev_err(dev, "unknown interconnect driver\n");		return 0;	} 	priv->icc_pdev = platform_device_register_data(			dev, icc_driver_name, -1, NULL, 0);	if (IS_ERR(priv->icc_pdev)) {		dev_err(dev, "failed to register icc provider %s: %ld\n",				icc_driver_name, PTR_ERR(priv->icc_pdev));		return PTR_ERR(priv->icc_pdev);	} 	return 0;} static int imx_bus_probe(struct platform_device *pdev){	struct device *dev = &pdev->dev;	struct imx_bus *priv;	const char *gov = DEVFREQ_GOV_USERSPACE;	int ret; 	priv = devm_kzalloc(dev, sizeof(*priv), GFP_KERNEL);	if (!priv)		return -ENOMEM; 	/*	 * Fetch the clock to adjust but don't explicitly enable.	 *	 * For imx bus clock clk_set_rate is safe no matter if the clock is on	 * or off and some peripheral side-buses might be off unless enabled by	 * drivers for devices on those specific buses.	 *	 * Rate adjustment on a disabled bus clock just takes effect later.	 */	priv->clk = devm_clk_get(dev, NULL);	if (IS_ERR(priv->clk)) {		ret = PTR_ERR(priv->clk);		dev_err(dev, "failed to fetch clk: %d\n", ret);		return ret;	}	platform_set_drvdata(pdev, priv); 	ret = dev_pm_opp_of_add_table(dev);	if (ret < 0) {		dev_err(dev, "failed to get OPP table\n");		return ret;	} 	priv->profile.target = imx_bus_target;	priv->profile.exit = imx_bus_exit;	priv->profile.get_cur_freq = imx_bus_get_cur_freq;	priv->profile.initial_freq = clk_get_rate(priv->clk); 	priv->devfreq = devm_devfreq_add_device(dev, &priv->profile,						gov, NULL);	if (IS_ERR(priv->devfreq)) {		ret = PTR_ERR(priv->devfreq);		dev_err(dev, "failed to add devfreq device: %d\n", ret);		goto err;	} 	ret = imx_bus_init_icc(dev);	if (ret)		goto err; 	return 0; err:	dev_pm_opp_of_remove_table(dev);	return ret;} static const struct of_device_id imx_bus_of_match[] = {	{ .compatible = "fsl,imx8mq-noc", .data = "imx8mq-interconnect", },	{ .compatible = "fsl,imx8mm-noc", .data = "imx8mm-interconnect", },	{ .compatible = "fsl,imx8mn-noc", .data = "imx8mn-interconnect", },	{ .compatible = "fsl,imx8mp-noc", .data = "imx8mp-interconnect", },	{ .compatible = "fsl,imx8m-noc", },	{ .compatible = "fsl,imx8m-nic", },	{ /* sentinel */ },};MODULE_DEVICE_TABLE(of, imx_bus_of_match); static struct platform_driver imx_bus_platdrv = {	.probe		= imx_bus_probe,	.driver = {		.name	= "imx-bus-devfreq",		.of_match_table = imx_bus_of_match,	},};module_platform_driver(imx_bus_platdrv); MODULE_DESCRIPTION("Generic i.MX bus frequency scaling driver");MODULE_AUTHOR("Leonard Crestez <leonard.crestez@nxp.com>");MODULE_LICENSE("GPL v2");