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/of_device.h>
  18 #include <linux/syscore_ops.h>
  19 #include <linux/module.h>
  20 #include <linux/platform_device.h>
  21 #include <linux/pm_runtime.h>
  22
  23 #include <dt-bindings/clock/exynos-audss-clk.h>
  24
  25 static DEFINE_SPINLOCK(lock);
  26 static void __iomem *reg_base;
  27 static struct clk_hw_onecell_data *clk_data;
  28 /*
  29  * On Exynos5420 this will be a clock which has to be enabled before any
  30  * access to audss registers. Typically a child of EPLL.
  31  *
  32  * On other platforms this will be -ENODEV.
  33  */
  34 static struct clk *epll;
  35
  36 #define ASS_CLK_SRC 0x0
  37 #define ASS_CLK_DIV 0x4
  38 #define ASS_CLK_GATE 0x8
  39
  40 static unsigned long reg_save[][2] = {
  41         { ASS_CLK_SRC,  0 },
  42         { ASS_CLK_DIV,  0 },
  43         { ASS_CLK_GATE, 0 },
  44 };
  45
  46 static int __maybe_unused exynos_audss_clk_suspend(struct device *dev)
  47 {
  48         int i;
  49
  50         for (i = 0; i < ARRAY_SIZE(reg_save); i++)
  51                 reg_save[i][1] = readl(reg_base + reg_save[i][0]);
  52
  53         return 0;
  54 }
  55
  56 static int __maybe_unused exynos_audss_clk_resume(struct device *dev)
  57 {
  58         int i;
  59
  60         for (i = 0; i < ARRAY_SIZE(reg_save); i++)
  61                 writel(reg_save[i][1], reg_base + reg_save[i][0]);
  62
  63         return 0;
  64 }
  65
  66 struct exynos_audss_clk_drvdata {
  67         unsigned int has_adma_clk:1;
  68         unsigned int has_mst_clk:1;
  69         unsigned int enable_epll:1;
  70         unsigned int num_clks;
  71 };
  72
  73 static const struct exynos_audss_clk_drvdata exynos4210_drvdata = {
  74         .num_clks       = EXYNOS_AUDSS_MAX_CLKS - 1,
  75         .enable_epll    = 1,
  76 };
  77
  78 static const struct exynos_audss_clk_drvdata exynos5410_drvdata = {
  79         .num_clks       = EXYNOS_AUDSS_MAX_CLKS - 1,
  80         .has_mst_clk    = 1,
  81 };
  82
  83 static const struct exynos_audss_clk_drvdata exynos5420_drvdata = {
  84         .num_clks       = EXYNOS_AUDSS_MAX_CLKS,
  85         .has_adma_clk   = 1,
  86         .enable_epll    = 1,
  87 };
  88
  89 static const struct of_device_id exynos_audss_clk_of_match[] = {
  90         {
  91                 .compatible     = "samsung,exynos4210-audss-clock",
  92                 .data           = &exynos4210_drvdata,
  93         }, {
  94                 .compatible     = "samsung,exynos5250-audss-clock",
  95                 .data           = &exynos4210_drvdata,
  96         }, {
  97                 .compatible     = "samsung,exynos5410-audss-clock",
  98                 .data           = &exynos5410_drvdata,
  99         }, {
 100                 .compatible     = "samsung,exynos5420-audss-clock",
 101                 .data           = &exynos5420_drvdata,
 102         },
 103         { },
 104 };
 105 MODULE_DEVICE_TABLE(of, exynos_audss_clk_of_match);
 106
 107 static void exynos_audss_clk_teardown(void)
 108 {
 109         int i;
 110
 111         for (i = EXYNOS_MOUT_AUDSS; i < EXYNOS_DOUT_SRP; i++) {
 112                 if (!IS_ERR(clk_data->hws[i]))
 113                         clk_hw_unregister_mux(clk_data->hws[i]);
 114         }
 115
 116         for (; i < EXYNOS_SRP_CLK; i++) {
 117                 if (!IS_ERR(clk_data->hws[i]))
 118                         clk_hw_unregister_divider(clk_data->hws[i]);
 119         }
 120
 121         for (; i < clk_data->num; i++) {
 122                 if (!IS_ERR(clk_data->hws[i]))
 123                         clk_hw_unregister_gate(clk_data->hws[i]);
 124         }
 125 }
 126
 127 /* register exynos_audss clocks */
 128 static int exynos_audss_clk_probe(struct platform_device *pdev)
 129 {
 130         const char *mout_audss_p[] = {"fin_pll", "fout_epll"};
 131         const char *mout_i2s_p[] = {"mout_audss", "cdclk0", "sclk_audio0"};
 132         const char *sclk_pcm_p = "sclk_pcm0";
 133         struct clk *pll_ref, *pll_in, *cdclk, *sclk_audio, *sclk_pcm_in;
 134         const struct exynos_audss_clk_drvdata *variant;
 135         struct clk_hw **clk_table;
 136         struct resource *res;
 137         struct device *dev = &pdev->dev;
 138         int i, ret = 0;
 139
 140         variant = of_device_get_match_data(&pdev->dev);
 141         if (!variant)
 142                 return -EINVAL;
 143
 144         res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
 145         reg_base = devm_ioremap_resource(dev, res);
 146         if (IS_ERR(reg_base))
 147                 return PTR_ERR(reg_base);
 148
 149         epll = ERR_PTR(-ENODEV);
 150
 151         clk_data = devm_kzalloc(dev,
 152                                 struct_size(clk_data, hws,
 153                                             EXYNOS_AUDSS_MAX_CLKS),
 154                                 GFP_KERNEL);
 155         if (!clk_data)
 156                 return -ENOMEM;
 157
 158         clk_data->num = variant->num_clks;
 159         clk_table = clk_data->hws;
 160
 161         pll_ref = devm_clk_get(dev, "pll_ref");
 162         pll_in = devm_clk_get(dev, "pll_in");
 163         if (!IS_ERR(pll_ref))
 164                 mout_audss_p[0] = __clk_get_name(pll_ref);
 165         if (!IS_ERR(pll_in)) {
 166                 mout_audss_p[1] = __clk_get_name(pll_in);
 167
 168                 if (variant->enable_epll) {
 169                         epll = pll_in;
 170
 171                         ret = clk_prepare_enable(epll);
 172                         if (ret) {
 173                                 dev_err(dev,
 174                                         "failed to prepare the epll clock\n");
 175                                 return ret;
 176                         }
 177                 }
 178         }
 179
 180         /*
 181          * Enable runtime PM here to allow the clock core using runtime PM
 182          * for the registered clocks. Additionally, we increase the runtime
 183          * PM usage count before registering the clocks, to prevent the
 184          * clock core from runtime suspending the device.
 185          */
 186         pm_runtime_get_noresume(dev);
 187         pm_runtime_set_active(dev);
 188         pm_runtime_enable(dev);
 189
 190         clk_table[EXYNOS_MOUT_AUDSS] = clk_hw_register_mux(dev, "mout_audss",
 191                                 mout_audss_p, ARRAY_SIZE(mout_audss_p),
 192                                 CLK_SET_RATE_NO_REPARENT | CLK_SET_RATE_PARENT,
 193                                 reg_base + ASS_CLK_SRC, 0, 1, 0, &lock);
 194
 195         cdclk = devm_clk_get(dev, "cdclk");
 196         sclk_audio = devm_clk_get(dev, "sclk_audio");
 197         if (!IS_ERR(cdclk))
 198                 mout_i2s_p[1] = __clk_get_name(cdclk);
 199         if (!IS_ERR(sclk_audio))
 200                 mout_i2s_p[2] = __clk_get_name(sclk_audio);
 201         clk_table[EXYNOS_MOUT_I2S] = clk_hw_register_mux(dev, "mout_i2s",
 202                                 mout_i2s_p, ARRAY_SIZE(mout_i2s_p),
 203                                 CLK_SET_RATE_NO_REPARENT,
 204                                 reg_base + ASS_CLK_SRC, 2, 2, 0, &lock);
 205
 206         clk_table[EXYNOS_DOUT_SRP] = clk_hw_register_divider(dev, "dout_srp",
 207                                 "mout_audss", CLK_SET_RATE_PARENT,
 208                                 reg_base + ASS_CLK_DIV, 0, 4, 0, &lock);
 209
 210         clk_table[EXYNOS_DOUT_AUD_BUS] = clk_hw_register_divider(dev,
 211                                 "dout_aud_bus", "dout_srp", CLK_SET_RATE_PARENT,
 212                                 reg_base + ASS_CLK_DIV, 4, 4, 0, &lock);
 213
 214         clk_table[EXYNOS_DOUT_I2S] = clk_hw_register_divider(dev, "dout_i2s",
 215                                 "mout_i2s", 0, reg_base + ASS_CLK_DIV, 8, 4, 0,
 216                                 &lock);
 217
 218         clk_table[EXYNOS_SRP_CLK] = clk_hw_register_gate(dev, "srp_clk",
 219                                 "dout_srp", CLK_SET_RATE_PARENT,
 220                                 reg_base + ASS_CLK_GATE, 0, 0, &lock);
 221
 222         clk_table[EXYNOS_I2S_BUS] = clk_hw_register_gate(dev, "i2s_bus",
 223                                 "dout_aud_bus", CLK_SET_RATE_PARENT,
 224                                 reg_base + ASS_CLK_GATE, 2, 0, &lock);
 225
 226         clk_table[EXYNOS_SCLK_I2S] = clk_hw_register_gate(dev, "sclk_i2s",
 227                                 "dout_i2s", CLK_SET_RATE_PARENT,
 228                                 reg_base + ASS_CLK_GATE, 3, 0, &lock);
 229
 230         clk_table[EXYNOS_PCM_BUS] = clk_hw_register_gate(dev, "pcm_bus",
 231                                  "sclk_pcm", CLK_SET_RATE_PARENT,
 232                                 reg_base + ASS_CLK_GATE, 4, 0, &lock);
 233
 234         sclk_pcm_in = devm_clk_get(dev, "sclk_pcm_in");
 235         if (!IS_ERR(sclk_pcm_in))
 236                 sclk_pcm_p = __clk_get_name(sclk_pcm_in);
 237         clk_table[EXYNOS_SCLK_PCM] = clk_hw_register_gate(dev, "sclk_pcm",
 238                                 sclk_pcm_p, CLK_SET_RATE_PARENT,
 239                                 reg_base + ASS_CLK_GATE, 5, 0, &lock);
 240
 241         if (variant->has_adma_clk) {
 242                 clk_table[EXYNOS_ADMA] = clk_hw_register_gate(dev, "adma",
 243                                 "dout_srp", CLK_SET_RATE_PARENT,
 244                                 reg_base + ASS_CLK_GATE, 9, 0, &lock);
 245         }
 246
 247         for (i = 0; i < clk_data->num; i++) {
 248                 if (IS_ERR(clk_table[i])) {
 249                         dev_err(dev, "failed to register clock %d\n", i);
 250                         ret = PTR_ERR(clk_table[i]);
 251                         goto unregister;
 252                 }
 253         }
 254
 255         ret = of_clk_add_hw_provider(dev->of_node, of_clk_hw_onecell_get,
 256                                      clk_data);
 257         if (ret) {
 258                 dev_err(dev, "failed to add clock provider\n");
 259                 goto unregister;
 260         }
 261
 262         pm_runtime_put_sync(dev);
 263
 264         return 0;
 265
 266 unregister:
 267         exynos_audss_clk_teardown();
 268         pm_runtime_put_sync(dev);
 269         pm_runtime_disable(dev);
 270
 271         if (!IS_ERR(epll))
 272                 clk_disable_unprepare(epll);
 273
 274         return ret;
 275 }
 276
 277 static int exynos_audss_clk_remove(struct platform_device *pdev)
 278 {
 279         of_clk_del_provider(pdev->dev.of_node);
 280
 281         exynos_audss_clk_teardown();
 282         pm_runtime_disable(&pdev->dev);
 283
 284         if (!IS_ERR(epll))
 285                 clk_disable_unprepare(epll);
 286
 287         return 0;
 288 }
 289
 290 static const struct dev_pm_ops exynos_audss_clk_pm_ops = {
 291         SET_RUNTIME_PM_OPS(exynos_audss_clk_suspend, exynos_audss_clk_resume,
 292                            NULL)
 293         SET_LATE_SYSTEM_SLEEP_PM_OPS(pm_runtime_force_suspend,
 294                                      pm_runtime_force_resume)
 295 };
 296
 297 static struct platform_driver exynos_audss_clk_driver = {
 298         .driver = {
 299                 .name = "exynos-audss-clk",
 300                 .of_match_table = exynos_audss_clk_of_match,
 301                 .pm = &exynos_audss_clk_pm_ops,
 302         },
 303         .probe = exynos_audss_clk_probe,
 304         .remove = exynos_audss_clk_remove,
 305 };
 306
 307 module_platform_driver(exynos_audss_clk_driver);
 308
 309 MODULE_AUTHOR("Padmavathi Venna <padma.v@samsung.com>");
 310 MODULE_DESCRIPTION("Exynos Audio Subsystem Clock Controller");
 311 MODULE_LICENSE("GPL v2");
 312 MODULE_ALIAS("platform:exynos-audss-clk");