1 /* 2 * Copyright (c) 2014 Samsung Electronics Co., Ltd. 3 * Author: Tomasz Figa <t.figa@samsung.com> 4 * 5 * This program is free software; you can redistribute it and/or modify 6 * it under the terms of the GNU General Public License version 2 as 7 * published by the Free Software Foundation. 8 * 9 * Clock driver for Exynos clock output 10 */ 11 12 #include <linux/slab.h> 13 #include <linux/clk.h> 14 #include <linux/clk-provider.h> 15 #include <linux/of.h> 16 #include <linux/of_address.h> 17 #include <linux/syscore_ops.h> 18 19 #define EXYNOS_CLKOUT_NR_CLKS 1 20 #define EXYNOS_CLKOUT_PARENTS 32 21 22 #define EXYNOS_PMU_DEBUG_REG 0xa00 23 #define EXYNOS_CLKOUT_DISABLE_SHIFT 0 24 #define EXYNOS_CLKOUT_MUX_SHIFT 8 25 #define EXYNOS4_CLKOUT_MUX_MASK 0xf 26 #define EXYNOS5_CLKOUT_MUX_MASK 0x1f 27 28 struct exynos_clkout { 29 struct clk_gate gate; 30 struct clk_mux mux; 31 spinlock_t slock; 32 struct clk_onecell_data data; 33 struct clk *clk_table[EXYNOS_CLKOUT_NR_CLKS]; 34 void __iomem *reg; 35 u32 pmu_debug_save; 36 }; 37 38 static struct exynos_clkout *clkout; 39 40 static int exynos_clkout_suspend(void) 41 { 42 clkout->pmu_debug_save = readl(clkout->reg + EXYNOS_PMU_DEBUG_REG); 43 44 return 0; 45 } 46 47 static void exynos_clkout_resume(void) 48 { 49 writel(clkout->pmu_debug_save, clkout->reg + EXYNOS_PMU_DEBUG_REG); 50 } 51 52 static struct syscore_ops exynos_clkout_syscore_ops = { 53 .suspend = exynos_clkout_suspend, 54 .resume = exynos_clkout_resume, 55 }; 56 57 static void __init exynos_clkout_init(struct device_node *node, u32 mux_mask) 58 { 59 const char *parent_names[EXYNOS_CLKOUT_PARENTS]; 60 struct clk *parents[EXYNOS_CLKOUT_PARENTS]; 61 int parent_count; 62 int ret; 63 int i; 64 65 clkout = kzalloc(sizeof(*clkout), GFP_KERNEL); 66 if (!clkout) 67 return; 68 69 spin_lock_init(&clkout->slock); 70 71 parent_count = 0; 72 for (i = 0; i < EXYNOS_CLKOUT_PARENTS; ++i) { 73 char name[] = "clkoutXX"; 74 75 snprintf(name, sizeof(name), "clkout%d", i); 76 parents[i] = of_clk_get_by_name(node, name); 77 if (IS_ERR(parents[i])) { 78 parent_names[i] = "none"; 79 continue; 80 } 81 82 parent_names[i] = __clk_get_name(parents[i]); 83 parent_count = i + 1; 84 } 85 86 if (!parent_count) 87 goto free_clkout; 88 89 clkout->reg = of_iomap(node, 0); 90 if (!clkout->reg) 91 goto clks_put; 92 93 clkout->gate.reg = clkout->reg + EXYNOS_PMU_DEBUG_REG; 94 clkout->gate.bit_idx = EXYNOS_CLKOUT_DISABLE_SHIFT; 95 clkout->gate.flags = CLK_GATE_SET_TO_DISABLE; 96 clkout->gate.lock = &clkout->slock; 97 98 clkout->mux.reg = clkout->reg + EXYNOS_PMU_DEBUG_REG; 99 clkout->mux.mask = mux_mask; 100 clkout->mux.shift = EXYNOS_CLKOUT_MUX_SHIFT; 101 clkout->mux.lock = &clkout->slock; 102 103 clkout->clk_table[0] = clk_register_composite(NULL, "clkout", 104 parent_names, parent_count, &clkout->mux.hw, 105 &clk_mux_ops, NULL, NULL, &clkout->gate.hw, 106 &clk_gate_ops, CLK_SET_RATE_PARENT 107 | CLK_SET_RATE_NO_REPARENT); 108 if (IS_ERR(clkout->clk_table[0])) 109 goto err_unmap; 110 111 clkout->data.clks = clkout->clk_table; 112 clkout->data.clk_num = EXYNOS_CLKOUT_NR_CLKS; 113 ret = of_clk_add_provider(node, of_clk_src_onecell_get, &clkout->data); 114 if (ret) 115 goto err_clk_unreg; 116 117 register_syscore_ops(&exynos_clkout_syscore_ops); 118 119 return; 120 121 err_clk_unreg: 122 clk_unregister(clkout->clk_table[0]); 123 err_unmap: 124 iounmap(clkout->reg); 125 clks_put: 126 for (i = 0; i < EXYNOS_CLKOUT_PARENTS; ++i) 127 if (!IS_ERR(parents[i])) 128 clk_put(parents[i]); 129 free_clkout: 130 kfree(clkout); 131 132 pr_err("%s: failed to register clkout clock\n", __func__); 133 } 134 135 static void __init exynos4_clkout_init(struct device_node *node) 136 { 137 exynos_clkout_init(node, EXYNOS4_CLKOUT_MUX_MASK); 138 } 139 CLK_OF_DECLARE(exynos4210_clkout, "samsung,exynos4210-pmu", 140 exynos4_clkout_init); 141 CLK_OF_DECLARE(exynos4212_clkout, "samsung,exynos4212-pmu", 142 exynos4_clkout_init); 143 CLK_OF_DECLARE(exynos4412_clkout, "samsung,exynos4412-pmu", 144 exynos4_clkout_init); 145 CLK_OF_DECLARE(exynos3250_clkout, "samsung,exynos3250-pmu", 146 exynos4_clkout_init); 147 148 static void __init exynos5_clkout_init(struct device_node *node) 149 { 150 exynos_clkout_init(node, EXYNOS5_CLKOUT_MUX_MASK); 151 } 152 CLK_OF_DECLARE(exynos5250_clkout, "samsung,exynos5250-pmu", 153 exynos5_clkout_init); 154 CLK_OF_DECLARE(exynos5420_clkout, "samsung,exynos5420-pmu", 155 exynos5_clkout_init); 156 CLK_OF_DECLARE(exynos5433_clkout, "samsung,exynos5433-pmu", 157 exynos5_clkout_init); 158