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1// SPDX-License-Identifier: GPL-2.0-or-later2/*3 * Copyright (C) 2016 Free Electrons4 *5 * Maxime Ripard <maxime.ripard@free-electrons.com>6 */7 8#include <linux/clk.h>9#include <linux/component.h>10#include <linux/module.h>11#include <linux/mod_devicetable.h>12#include <linux/platform_device.h>13#include <linux/regmap.h>14#include <linux/reset.h>15 16struct sun6i_drc {17 struct clk *bus_clk;18 struct clk *mod_clk;19 struct reset_control *reset;20};21 22static int sun6i_drc_bind(struct device *dev, struct device *master,23 void *data)24{25 struct sun6i_drc *drc;26 int ret;27 28 drc = devm_kzalloc(dev, sizeof(*drc), GFP_KERNEL);29 if (!drc)30 return -ENOMEM;31 dev_set_drvdata(dev, drc);32 33 drc->reset = devm_reset_control_get(dev, NULL);34 if (IS_ERR(drc->reset)) {35 dev_err(dev, "Couldn't get our reset line\n");36 return PTR_ERR(drc->reset);37 }38 39 ret = reset_control_deassert(drc->reset);40 if (ret) {41 dev_err(dev, "Couldn't deassert our reset line\n");42 return ret;43 }44 45 drc->bus_clk = devm_clk_get(dev, "ahb");46 if (IS_ERR(drc->bus_clk)) {47 dev_err(dev, "Couldn't get our bus clock\n");48 ret = PTR_ERR(drc->bus_clk);49 goto err_assert_reset;50 }51 clk_prepare_enable(drc->bus_clk);52 53 drc->mod_clk = devm_clk_get(dev, "mod");54 if (IS_ERR(drc->mod_clk)) {55 dev_err(dev, "Couldn't get our mod clock\n");56 ret = PTR_ERR(drc->mod_clk);57 goto err_disable_bus_clk;58 }59 60 ret = clk_set_rate_exclusive(drc->mod_clk, 300000000);61 if (ret) {62 dev_err(dev, "Couldn't set the module clock frequency\n");63 goto err_disable_bus_clk;64 }65 66 clk_prepare_enable(drc->mod_clk);67 68 return 0;69 70err_disable_bus_clk:71 clk_disable_unprepare(drc->bus_clk);72err_assert_reset:73 reset_control_assert(drc->reset);74 return ret;75}76 77static void sun6i_drc_unbind(struct device *dev, struct device *master,78 void *data)79{80 struct sun6i_drc *drc = dev_get_drvdata(dev);81 82 clk_rate_exclusive_put(drc->mod_clk);83 clk_disable_unprepare(drc->mod_clk);84 clk_disable_unprepare(drc->bus_clk);85 reset_control_assert(drc->reset);86}87 88static const struct component_ops sun6i_drc_ops = {89 .bind = sun6i_drc_bind,90 .unbind = sun6i_drc_unbind,91};92 93static int sun6i_drc_probe(struct platform_device *pdev)94{95 return component_add(&pdev->dev, &sun6i_drc_ops);96}97 98static void sun6i_drc_remove(struct platform_device *pdev)99{100 component_del(&pdev->dev, &sun6i_drc_ops);101}102 103static const struct of_device_id sun6i_drc_of_table[] = {104 { .compatible = "allwinner,sun6i-a31-drc" },105 { .compatible = "allwinner,sun6i-a31s-drc" },106 { .compatible = "allwinner,sun8i-a23-drc" },107 { .compatible = "allwinner,sun8i-a33-drc" },108 { .compatible = "allwinner,sun9i-a80-drc" },109 { }110};111MODULE_DEVICE_TABLE(of, sun6i_drc_of_table);112 113static struct platform_driver sun6i_drc_platform_driver = {114 .probe = sun6i_drc_probe,115 .remove_new = sun6i_drc_remove,116 .driver = {117 .name = "sun6i-drc",118 .of_match_table = sun6i_drc_of_table,119 },120};121module_platform_driver(sun6i_drc_platform_driver);122 123MODULE_AUTHOR("Maxime Ripard <maxime.ripard@free-electrons.com>");124MODULE_DESCRIPTION("Allwinner A31 Dynamic Range Control (DRC) Driver");125MODULE_LICENSE("GPL");126