kernel/drivers/clk/samsung/clk-exynos-audss.c

   1 /*
   2  * Copyright (c) 2013 Samsung Electronics Co., Ltd.
   3  * Author: Padmavathi Venna <padma.v@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  * Common Clock Framework support for Audio Subsystem Clock Controller.
  10 */
  11
  12 #include <linux/slab.h>
  13 #include <linux/io.h>
  14 #include <linux/clk.h>
  15 #include <linux/clk-provider.h>
  16 #include <linux/of_address.h>
  17 #include <linux/syscore_ops.h>
  18 #include <linux/module.h>
  19 #include <linux/platform_device.h>
  20
  21 #include <dt-bindings/clock/exynos-audss-clk.h>
  22
  23 enum exynos_audss_clk_type {
  24         TYPE_EXYNOS4210,
  25         TYPE_EXYNOS5250,
  26         TYPE_EXYNOS5420,
  27 };
  28
  29 static DEFINE_SPINLOCK(lock);
  30 static struct clk **clk_table;
  31 static void __iomem *reg_base;
  32 static struct clk_onecell_data clk_data;
  33 /*
  34  * On Exynos5420 this will be a clock which has to be enabled before any
  35  * access to audss registers. Typically a child of EPLL.
  36  *
  37  * On other platforms this will be -ENODEV.
  38  */
  39 static struct clk *epll;
  40
  41 #define ASS_CLK_SRC 0x0
  42 #define ASS_CLK_DIV 0x4
  43 #define ASS_CLK_GATE 0x8
  44
  45 #ifdef CONFIG_PM_SLEEP
  46 static unsigned long reg_save[][2] = {
  47         {ASS_CLK_SRC,  0},
  48         {ASS_CLK_DIV,  0},
  49         {ASS_CLK_GATE, 0},
  50 };
  51
  52 static int exynos_audss_clk_suspend(void)
  53 {
  54         int i;
  55
  56         for (i = 0; i < ARRAY_SIZE(reg_save); i++)
  57                 reg_save[i][1] = readl(reg_base + reg_save[i][0]);
  58
  59         return 0;
  60 }
  61
  62 static void exynos_audss_clk_resume(void)
  63 {
  64         int i;
  65
  66         for (i = 0; i < ARRAY_SIZE(reg_save); i++)
  67                 writel(reg_save[i][1], reg_base + reg_save[i][0]);
  68 }
  69
  70 static struct syscore_ops exynos_audss_clk_syscore_ops = {
  71         .suspend        = exynos_audss_clk_suspend,
  72         .resume         = exynos_audss_clk_resume,
  73 };
  74 #endif /* CONFIG_PM_SLEEP */
  75
  76 static const struct of_device_id exynos_audss_clk_of_match[] = {
  77         { .compatible = "samsung,exynos4210-audss-clock",
  78           .data = (void *)TYPE_EXYNOS4210, },
  79         { .compatible = "samsung,exynos5250-audss-clock",
  80           .data = (void *)TYPE_EXYNOS5250, },
  81         { .compatible = "samsung,exynos5420-audss-clock",
  82           .data = (void *)TYPE_EXYNOS5420, },
  83         {},
  84 };
  85
  86 static void exynos_audss_clk_teardown(void)
  87 {
  88         int i;
  89
  90         for (i = EXYNOS_MOUT_AUDSS; i < EXYNOS_DOUT_SRP; i++) {
  91                 if (!IS_ERR(clk_table[i]))
  92                         clk_unregister_mux(clk_table[i]);
  93         }
  94
  95         for (; i < EXYNOS_SRP_CLK; i++) {
  96                 if (!IS_ERR(clk_table[i]))
  97                         clk_unregister_divider(clk_table[i]);
  98         }
  99
 100         for (; i < clk_data.clk_num; i++) {
 101                 if (!IS_ERR(clk_table[i]))
 102                         clk_unregister_gate(clk_table[i]);
 103         }
 104 }
 105
 106 /* register exynos_audss clocks */
 107 static int exynos_audss_clk_probe(struct platform_device *pdev)
 108 {
 109         int i, ret = 0;
 110         struct resource *res;
 111         const char *mout_audss_p[] = {"fin_pll", "fout_epll"};
 112         const char *mout_i2s_p[] = {"mout_audss", "cdclk0", "sclk_audio0"};
 113         const char *sclk_pcm_p = "sclk_pcm0";
 114         struct clk *pll_ref, *pll_in, *cdclk, *sclk_audio, *sclk_pcm_in;
 115         const struct of_device_id *match;
 116         enum exynos_audss_clk_type variant;
 117
 118         match = of_match_node(exynos_audss_clk_of_match, pdev->dev.of_node);
 119         if (!match)
 120                 return -EINVAL;
 121         variant = (enum exynos_audss_clk_type)match->data;
 122
 123         res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
 124         reg_base = devm_ioremap_resource(&pdev->dev, res);
 125         if (IS_ERR(reg_base)) {
 126                 dev_err(&pdev->dev, "failed to map audss registers\n");
 127                 return PTR_ERR(reg_base);
 128         }
 129         /* EPLL don't have to be enabled for boards other than Exynos5420 */
 130         epll = ERR_PTR(-ENODEV);
 131
 132         clk_table = devm_kzalloc(&pdev->dev,
 133                                 sizeof(struct clk *) * EXYNOS_AUDSS_MAX_CLKS,
 134                                 GFP_KERNEL);
 135         if (!clk_table)
 136                 return -ENOMEM;
 137
 138         clk_data.clks = clk_table;
 139         if (variant == TYPE_EXYNOS5420)
 140                 clk_data.clk_num = EXYNOS_AUDSS_MAX_CLKS;
 141         else
 142                 clk_data.clk_num = EXYNOS_AUDSS_MAX_CLKS - 1;
 143
 144         pll_ref = devm_clk_get(&pdev->dev, "pll_ref");
 145         pll_in = devm_clk_get(&pdev->dev, "pll_in");
 146         if (!IS_ERR(pll_ref))
 147                 mout_audss_p[0] = __clk_get_name(pll_ref);
 148         if (!IS_ERR(pll_in)) {
 149                 mout_audss_p[1] = __clk_get_name(pll_in);
 150
 151                 if (variant == TYPE_EXYNOS5420) {
 152                         epll = pll_in;
 153
 154                         ret = clk_prepare_enable(epll);
 155                         if (ret) {
 156                                 dev_err(&pdev->dev,
 157                                                 "failed to prepare the epll clock\n");
 158                                 return ret;
 159                         }
 160                 }
 161         }
 162         clk_table[EXYNOS_MOUT_AUDSS] = clk_register_mux(NULL, "mout_audss",
 163                                 mout_audss_p, ARRAY_SIZE(mout_audss_p),
 164                                 CLK_SET_RATE_NO_REPARENT,
 165                                 reg_base + ASS_CLK_SRC, 0, 1, 0, &lock);
 166
 167         cdclk = devm_clk_get(&pdev->dev, "cdclk");
 168         sclk_audio = devm_clk_get(&pdev->dev, "sclk_audio");
 169         if (!IS_ERR(cdclk))
 170                 mout_i2s_p[1] = __clk_get_name(cdclk);
 171         if (!IS_ERR(sclk_audio))
 172                 mout_i2s_p[2] = __clk_get_name(sclk_audio);
 173         clk_table[EXYNOS_MOUT_I2S] = clk_register_mux(NULL, "mout_i2s",
 174                                 mout_i2s_p, ARRAY_SIZE(mout_i2s_p),
 175                                 CLK_SET_RATE_NO_REPARENT,
 176                                 reg_base + ASS_CLK_SRC, 2, 2, 0, &lock);
 177
 178         clk_table[EXYNOS_DOUT_SRP] = clk_register_divider(NULL, "dout_srp",
 179                                 "mout_audss", 0, reg_base + ASS_CLK_DIV, 0, 4,
 180                                 0, &lock);
 181
 182         clk_table[EXYNOS_DOUT_AUD_BUS] = clk_register_divider(NULL,
 183                                 "dout_aud_bus", "dout_srp", 0,
 184                                 reg_base + ASS_CLK_DIV, 4, 4, 0, &lock);
 185
 186         clk_table[EXYNOS_DOUT_I2S] = clk_register_divider(NULL, "dout_i2s",
 187                                 "mout_i2s", 0, reg_base + ASS_CLK_DIV, 8, 4, 0,
 188                                 &lock);
 189
 190         clk_table[EXYNOS_SRP_CLK] = clk_register_gate(NULL, "srp_clk",
 191                                 "dout_srp", CLK_SET_RATE_PARENT,
 192                                 reg_base + ASS_CLK_GATE, 0, 0, &lock);
 193
 194         clk_table[EXYNOS_I2S_BUS] = clk_register_gate(NULL, "i2s_bus",
 195                                 "dout_aud_bus", CLK_SET_RATE_PARENT,
 196                                 reg_base + ASS_CLK_GATE, 2, 0, &lock);
 197
 198         clk_table[EXYNOS_SCLK_I2S] = clk_register_gate(NULL, "sclk_i2s",
 199                                 "dout_i2s", CLK_SET_RATE_PARENT,
 200                                 reg_base + ASS_CLK_GATE, 3, 0, &lock);
 201
 202         clk_table[EXYNOS_PCM_BUS] = clk_register_gate(NULL, "pcm_bus",
 203                                  "sclk_pcm", CLK_SET_RATE_PARENT,
 204                                 reg_base + ASS_CLK_GATE, 4, 0, &lock);
 205
 206         sclk_pcm_in = devm_clk_get(&pdev->dev, "sclk_pcm_in");
 207         if (!IS_ERR(sclk_pcm_in))
 208                 sclk_pcm_p = __clk_get_name(sclk_pcm_in);
 209         clk_table[EXYNOS_SCLK_PCM] = clk_register_gate(NULL, "sclk_pcm",
 210                                 sclk_pcm_p, CLK_SET_RATE_PARENT,
 211                                 reg_base + ASS_CLK_GATE, 5, 0, &lock);
 212
 213         if (variant == TYPE_EXYNOS5420) {
 214                 clk_table[EXYNOS_ADMA] = clk_register_gate(NULL, "adma",
 215                                 "dout_srp", CLK_SET_RATE_PARENT,
 216                                 reg_base + ASS_CLK_GATE, 9, 0, &lock);
 217         }
 218
 219         for (i = 0; i < clk_data.clk_num; i++) {
 220                 if (IS_ERR(clk_table[i])) {
 221                         dev_err(&pdev->dev, "failed to register clock %d\n", i);
 222                         ret = PTR_ERR(clk_table[i]);
 223                         goto unregister;
 224                 }
 225         }
 226
 227         ret = of_clk_add_provider(pdev->dev.of_node, of_clk_src_onecell_get,
 228                                         &clk_data);
 229         if (ret) {
 230                 dev_err(&pdev->dev, "failed to add clock provider\n");
 231                 goto unregister;
 232         }
 233
 234 #ifdef CONFIG_PM_SLEEP
 235         register_syscore_ops(&exynos_audss_clk_syscore_ops);
 236 #endif
 237
 238         dev_info(&pdev->dev, "setup completed\n");
 239
 240         return 0;
 241
 242 unregister:
 243         exynos_audss_clk_teardown();
 244
 245         if (!IS_ERR(epll))
 246                 clk_disable_unprepare(epll);
 247
 248         return ret;
 249 }
 250
 251 static int exynos_audss_clk_remove(struct platform_device *pdev)
 252 {
 253 #ifdef CONFIG_PM_SLEEP
 254         unregister_syscore_ops(&exynos_audss_clk_syscore_ops);
 255 #endif
 256
 257         of_clk_del_provider(pdev->dev.of_node);
 258
 259         exynos_audss_clk_teardown();
 260
 261         if (!IS_ERR(epll))
 262                 clk_disable_unprepare(epll);
 263
 264         return 0;
 265 }
 266
 267 static struct platform_driver exynos_audss_clk_driver = {
 268         .driver = {
 269                 .name = "exynos-audss-clk",
 270                 .of_match_table = exynos_audss_clk_of_match,
 271         },
 272         .probe = exynos_audss_clk_probe,
 273         .remove = exynos_audss_clk_remove,
 274 };
 275
 276 static int __init exynos_audss_clk_init(void)
 277 {
 278         return platform_driver_register(&exynos_audss_clk_driver);
 279 }
 280 core_initcall(exynos_audss_clk_init);
 281
 282 static void __exit exynos_audss_clk_exit(void)
 283 {
 284         platform_driver_unregister(&exynos_audss_clk_driver);
 285 }
 286 module_exit(exynos_audss_clk_exit);
 287
 288 MODULE_AUTHOR("Padmavathi Venna <padma.v@samsung.com>");
 289 MODULE_DESCRIPTION("Exynos Audio Subsystem Clock Controller");
 290 MODULE_LICENSE("GPL v2");
 291 MODULE_ALIAS("platform:exynos-audss-clk");