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1// SPDX-License-Identifier: GPL-2.0-only2/*3 * Copyright (c) 2014 Samsung Electronics Co., Ltd.4 * Author: Tomasz Figa <t.figa@samsung.com>5 *6 * Clock driver for Exynos clock output7 */8 9#include <linux/slab.h>10#include <linux/clk.h>11#include <linux/clk-provider.h>12#include <linux/module.h>13#include <linux/io.h>14#include <linux/of.h>15#include <linux/of_address.h>16#include <linux/of_device.h>17#include <linux/platform_device.h>18#include <linux/pm.h>19 20#define DRV_NAME "exynos-clkout"21 22#define EXYNOS_CLKOUT_NR_CLKS 123#define EXYNOS_CLKOUT_PARENTS 3224 25#define EXYNOS_PMU_DEBUG_REG 0xa0026#define EXYNOS_CLKOUT_DISABLE_SHIFT 027#define EXYNOS_CLKOUT_MUX_SHIFT 828#define EXYNOS4_CLKOUT_MUX_MASK 0xf29#define EXYNOS5_CLKOUT_MUX_MASK 0x1f30 31struct exynos_clkout {32 struct clk_gate gate;33 struct clk_mux mux;34 spinlock_t slock;35 void __iomem *reg;36 struct device_node *np;37 u32 pmu_debug_save;38 struct clk_hw_onecell_data data;39};40 41struct exynos_clkout_variant {42 u32 mux_mask;43};44 45static const struct exynos_clkout_variant exynos_clkout_exynos4 = {46 .mux_mask = EXYNOS4_CLKOUT_MUX_MASK,47};48 49static const struct exynos_clkout_variant exynos_clkout_exynos5 = {50 .mux_mask = EXYNOS5_CLKOUT_MUX_MASK,51};52 53static const struct of_device_id exynos_clkout_ids[] = {54 {55 .compatible = "samsung,exynos3250-pmu",56 .data = &exynos_clkout_exynos4,57 }, {58 .compatible = "samsung,exynos4210-pmu",59 .data = &exynos_clkout_exynos4,60 }, {61 .compatible = "samsung,exynos4212-pmu",62 .data = &exynos_clkout_exynos4,63 }, {64 .compatible = "samsung,exynos4412-pmu",65 .data = &exynos_clkout_exynos4,66 }, {67 .compatible = "samsung,exynos5250-pmu",68 .data = &exynos_clkout_exynos5,69 }, {70 .compatible = "samsung,exynos5410-pmu",71 .data = &exynos_clkout_exynos5,72 }, {73 .compatible = "samsung,exynos5420-pmu",74 .data = &exynos_clkout_exynos5,75 }, {76 .compatible = "samsung,exynos5433-pmu",77 .data = &exynos_clkout_exynos5,78 }, { }79};80 81/*82 * Device will be instantiated as child of PMU device without its own83 * device node. Therefore match compatibles against parent.84 */85static int exynos_clkout_match_parent_dev(struct device *dev, u32 *mux_mask)86{87 const struct exynos_clkout_variant *variant;88 const struct of_device_id *match;89 90 if (!dev->parent) {91 dev_err(dev, "not instantiated from MFD\n");92 return -EINVAL;93 }94 95 /*96 * 'exynos_clkout_ids' arrays is not the ids array matched by97 * the dev->parent driver, so of_device_get_match_data() or98 * device_get_match_data() cannot be used here.99 */100 match = of_match_device(exynos_clkout_ids, dev->parent);101 if (!match) {102 dev_err(dev, "cannot match parent device\n");103 return -EINVAL;104 }105 variant = match->data;106 107 *mux_mask = variant->mux_mask;108 109 return 0;110}111 112static int exynos_clkout_probe(struct platform_device *pdev)113{114 const char *parent_names[EXYNOS_CLKOUT_PARENTS];115 struct clk *parents[EXYNOS_CLKOUT_PARENTS];116 struct exynos_clkout *clkout;117 int parent_count, ret, i;118 u32 mux_mask;119 120 clkout = devm_kzalloc(&pdev->dev,121 struct_size(clkout, data.hws, EXYNOS_CLKOUT_NR_CLKS),122 GFP_KERNEL);123 if (!clkout)124 return -ENOMEM;125 126 ret = exynos_clkout_match_parent_dev(&pdev->dev, &mux_mask);127 if (ret)128 return ret;129 130 clkout->np = pdev->dev.of_node;131 if (!clkout->np) {132 /*133 * pdev->dev.parent was checked by exynos_clkout_match_parent_dev()134 * so it is not NULL.135 */136 clkout->np = pdev->dev.parent->of_node;137 }138 139 platform_set_drvdata(pdev, clkout);140 141 spin_lock_init(&clkout->slock);142 143 parent_count = 0;144 for (i = 0; i < EXYNOS_CLKOUT_PARENTS; ++i) {145 char name[] = "clkoutXX";146 147 snprintf(name, sizeof(name), "clkout%d", i);148 parents[i] = of_clk_get_by_name(clkout->np, name);149 if (IS_ERR(parents[i])) {150 parent_names[i] = "none";151 continue;152 }153 154 parent_names[i] = __clk_get_name(parents[i]);155 parent_count = i + 1;156 }157 158 if (!parent_count)159 return -EINVAL;160 161 clkout->reg = of_iomap(clkout->np, 0);162 if (!clkout->reg) {163 ret = -ENODEV;164 goto clks_put;165 }166 167 clkout->gate.reg = clkout->reg + EXYNOS_PMU_DEBUG_REG;168 clkout->gate.bit_idx = EXYNOS_CLKOUT_DISABLE_SHIFT;169 clkout->gate.flags = CLK_GATE_SET_TO_DISABLE;170 clkout->gate.lock = &clkout->slock;171 172 clkout->mux.reg = clkout->reg + EXYNOS_PMU_DEBUG_REG;173 clkout->mux.mask = mux_mask;174 clkout->mux.shift = EXYNOS_CLKOUT_MUX_SHIFT;175 clkout->mux.lock = &clkout->slock;176 177 clkout->data.hws[0] = clk_hw_register_composite(NULL, "clkout",178 parent_names, parent_count, &clkout->mux.hw,179 &clk_mux_ops, NULL, NULL, &clkout->gate.hw,180 &clk_gate_ops, CLK_SET_RATE_PARENT181 | CLK_SET_RATE_NO_REPARENT);182 if (IS_ERR(clkout->data.hws[0])) {183 ret = PTR_ERR(clkout->data.hws[0]);184 goto err_unmap;185 }186 187 clkout->data.num = EXYNOS_CLKOUT_NR_CLKS;188 ret = of_clk_add_hw_provider(clkout->np, of_clk_hw_onecell_get, &clkout->data);189 if (ret)190 goto err_clk_unreg;191 192 return 0;193 194err_clk_unreg:195 clk_hw_unregister(clkout->data.hws[0]);196err_unmap:197 iounmap(clkout->reg);198clks_put:199 for (i = 0; i < EXYNOS_CLKOUT_PARENTS; ++i)200 if (!IS_ERR(parents[i]))201 clk_put(parents[i]);202 203 dev_err(&pdev->dev, "failed to register clkout clock\n");204 205 return ret;206}207 208static void exynos_clkout_remove(struct platform_device *pdev)209{210 struct exynos_clkout *clkout = platform_get_drvdata(pdev);211 212 of_clk_del_provider(clkout->np);213 clk_hw_unregister(clkout->data.hws[0]);214 iounmap(clkout->reg);215}216 217static int __maybe_unused exynos_clkout_suspend(struct device *dev)218{219 struct exynos_clkout *clkout = dev_get_drvdata(dev);220 221 clkout->pmu_debug_save = readl(clkout->reg + EXYNOS_PMU_DEBUG_REG);222 223 return 0;224}225 226static int __maybe_unused exynos_clkout_resume(struct device *dev)227{228 struct exynos_clkout *clkout = dev_get_drvdata(dev);229 230 writel(clkout->pmu_debug_save, clkout->reg + EXYNOS_PMU_DEBUG_REG);231 232 return 0;233}234 235static SIMPLE_DEV_PM_OPS(exynos_clkout_pm_ops, exynos_clkout_suspend,236 exynos_clkout_resume);237 238static struct platform_driver exynos_clkout_driver = {239 .driver = {240 .name = DRV_NAME,241 .pm = &exynos_clkout_pm_ops,242 },243 .probe = exynos_clkout_probe,244 .remove = exynos_clkout_remove,245};246module_platform_driver(exynos_clkout_driver);247 248MODULE_AUTHOR("Krzysztof Kozlowski <krzk@kernel.org>");249MODULE_AUTHOR("Tomasz Figa <tomasz.figa@gmail.com>");250MODULE_DESCRIPTION("Samsung Exynos clock output driver");251MODULE_ALIAS("platform:" DRV_NAME);252MODULE_LICENSE("GPL");253