kernel/drivers/clk/samsung/clk-s3c2410-dclk.c

   1 /*
   2  * Copyright (c) 2013 Heiko Stuebner <heiko@sntech.de>
   3  *
   4  * This program is free software; you can redistribute it and/or modify
   5  * it under the terms of the GNU General Public License version 2 as
   6  * published by the Free Software Foundation.
   7  *
   8  * Common Clock Framework support for s3c24xx external clock output.
   9  */
  10
  11 #include <linux/platform_device.h>
  12 #include <linux/module.h>
  13 #include "clk.h"
  14
  15 /* legacy access to misccr, until dt conversion is finished */
  16 #include <mach/hardware.h>
  17 #include <mach/regs-gpio.h>
  18
  19 #define MUX_DCLK0       0
  20 #define MUX_DCLK1       1
  21 #define DIV_DCLK0       2
  22 #define DIV_DCLK1       3
  23 #define GATE_DCLK0      4
  24 #define GATE_DCLK1      5
  25 #define MUX_CLKOUT0     6
  26 #define MUX_CLKOUT1     7
  27 #define DCLK_MAX_CLKS   (MUX_CLKOUT1 + 1)
  28
  29 enum supported_socs {
  30         S3C2410,
  31         S3C2412,
  32         S3C2440,
  33         S3C2443,
  34 };
  35
  36 struct s3c24xx_dclk_drv_data {
  37         const char **clkout0_parent_names;
  38         int clkout0_num_parents;
  39         const char **clkout1_parent_names;
  40         int clkout1_num_parents;
  41         const char **mux_parent_names;
  42         int mux_num_parents;
  43 };
  44
  45 /*
  46  * Clock for output-parent selection in misccr
  47  */
  48
  49 struct s3c24xx_clkout {
  50         struct clk_hw           hw;
  51         u32                     mask;
  52         u8                      shift;
  53 };
  54
  55 #define to_s3c24xx_clkout(_hw) container_of(_hw, struct s3c24xx_clkout, hw)
  56
  57 static u8 s3c24xx_clkout_get_parent(struct clk_hw *hw)
  58 {
  59         struct s3c24xx_clkout *clkout = to_s3c24xx_clkout(hw);
  60         int num_parents = __clk_get_num_parents(hw->clk);
  61         u32 val;
  62
  63         val = readl_relaxed(S3C24XX_MISCCR) >> clkout->shift;
  64         val >>= clkout->shift;
  65         val &= clkout->mask;
  66
  67         if (val >= num_parents)
  68                 return -EINVAL;
  69
  70         return val;
  71 }
  72
  73 static int s3c24xx_clkout_set_parent(struct clk_hw *hw, u8 index)
  74 {
  75         struct s3c24xx_clkout *clkout = to_s3c24xx_clkout(hw);
  76         int ret = 0;
  77
  78         s3c2410_modify_misccr((clkout->mask << clkout->shift),
  79                               (index << clkout->shift));
  80
  81         return ret;
  82 }
  83
  84 const struct clk_ops s3c24xx_clkout_ops = {
  85         .get_parent = s3c24xx_clkout_get_parent,
  86         .set_parent = s3c24xx_clkout_set_parent,
  87         .determine_rate = __clk_mux_determine_rate,
  88 };
  89
  90 struct clk *s3c24xx_register_clkout(struct device *dev, const char *name,
  91                 const char **parent_names, u8 num_parents,
  92                 u8 shift, u32 mask)
  93 {
  94         struct s3c24xx_clkout *clkout;
  95         struct clk *clk;
  96         struct clk_init_data init;
  97
  98         /* allocate the clkout */
  99         clkout = kzalloc(sizeof(*clkout), GFP_KERNEL);
 100         if (!clkout)
 101                 return ERR_PTR(-ENOMEM);
 102
 103         init.name = name;
 104         init.ops = &s3c24xx_clkout_ops;
 105         init.flags = CLK_IS_BASIC;
 106         init.parent_names = parent_names;
 107         init.num_parents = num_parents;
 108
 109         clkout->shift = shift;
 110         clkout->mask = mask;
 111         clkout->hw.init = &init;
 112
 113         clk = clk_register(dev, &clkout->hw);
 114
 115         return clk;
 116 }
 117
 118 /*
 119  * dclk and clkout init
 120  */
 121
 122 struct s3c24xx_dclk {
 123         struct device *dev;
 124         void __iomem *base;
 125         struct clk_onecell_data clk_data;
 126         struct notifier_block dclk0_div_change_nb;
 127         struct notifier_block dclk1_div_change_nb;
 128         spinlock_t dclk_lock;
 129         unsigned long reg_save;
 130 };
 131
 132 #define to_s3c24xx_dclk0(x) \
 133                 container_of(x, struct s3c24xx_dclk, dclk0_div_change_nb)
 134
 135 #define to_s3c24xx_dclk1(x) \
 136                 container_of(x, struct s3c24xx_dclk, dclk1_div_change_nb)
 137
 138 static const char *dclk_s3c2410_p[] = { "pclk", "uclk" };
 139 static const char *clkout0_s3c2410_p[] = { "mpll", "upll", "fclk", "hclk", "pclk",
 140                              "gate_dclk0" };
 141 static const char *clkout1_s3c2410_p[] = { "mpll", "upll", "fclk", "hclk", "pclk",
 142                              "gate_dclk1" };
 143
 144 static const char *clkout0_s3c2412_p[] = { "mpll", "upll", "rtc_clkout",
 145                              "hclk", "pclk", "gate_dclk0" };
 146 static const char *clkout1_s3c2412_p[] = { "xti", "upll", "fclk", "hclk", "pclk",
 147                              "gate_dclk1" };
 148
 149 static const char *clkout0_s3c2440_p[] = { "xti", "upll", "fclk", "hclk", "pclk",
 150                              "gate_dclk0" };
 151 static const char *clkout1_s3c2440_p[] = { "mpll", "upll", "rtc_clkout",
 152                              "hclk", "pclk", "gate_dclk1" };
 153
 154 static const char *dclk_s3c2443_p[] = { "pclk", "epll" };
 155 static const char *clkout0_s3c2443_p[] = { "xti", "epll", "armclk", "hclk", "pclk",
 156                              "gate_dclk0" };
 157 static const char *clkout1_s3c2443_p[] = { "dummy", "epll", "rtc_clkout",
 158                              "hclk", "pclk", "gate_dclk1" };
 159
 160 #define DCLKCON_DCLK_DIV_MASK           0xf
 161 #define DCLKCON_DCLK0_DIV_SHIFT         4
 162 #define DCLKCON_DCLK0_CMP_SHIFT         8
 163 #define DCLKCON_DCLK1_DIV_SHIFT         20
 164 #define DCLKCON_DCLK1_CMP_SHIFT         24
 165
 166 static void s3c24xx_dclk_update_cmp(struct s3c24xx_dclk *s3c24xx_dclk,
 167                                     int div_shift, int cmp_shift)
 168 {
 169         unsigned long flags = 0;
 170         u32 dclk_con, div, cmp;
 171
 172         spin_lock_irqsave(&s3c24xx_dclk->dclk_lock, flags);
 173
 174         dclk_con = readl_relaxed(s3c24xx_dclk->base);
 175
 176         div = ((dclk_con >> div_shift) & DCLKCON_DCLK_DIV_MASK) + 1;
 177         cmp = ((div + 1) / 2) - 1;
 178
 179         dclk_con &= ~(DCLKCON_DCLK_DIV_MASK << cmp_shift);
 180         dclk_con |= (cmp << cmp_shift);
 181
 182         writel_relaxed(dclk_con, s3c24xx_dclk->base);
 183
 184         spin_unlock_irqrestore(&s3c24xx_dclk->dclk_lock, flags);
 185 }
 186
 187 static int s3c24xx_dclk0_div_notify(struct notifier_block *nb,
 188                                unsigned long event, void *data)
 189 {
 190         struct s3c24xx_dclk *s3c24xx_dclk = to_s3c24xx_dclk0(nb);
 191
 192         if (event == POST_RATE_CHANGE) {
 193                 s3c24xx_dclk_update_cmp(s3c24xx_dclk,
 194                         DCLKCON_DCLK0_DIV_SHIFT, DCLKCON_DCLK0_CMP_SHIFT);
 195         }
 196
 197         return NOTIFY_DONE;
 198 }
 199
 200 static int s3c24xx_dclk1_div_notify(struct notifier_block *nb,
 201                                unsigned long event, void *data)
 202 {
 203         struct s3c24xx_dclk *s3c24xx_dclk = to_s3c24xx_dclk1(nb);
 204
 205         if (event == POST_RATE_CHANGE) {
 206                 s3c24xx_dclk_update_cmp(s3c24xx_dclk,
 207                         DCLKCON_DCLK1_DIV_SHIFT, DCLKCON_DCLK1_CMP_SHIFT);
 208         }
 209
 210         return NOTIFY_DONE;
 211 }
 212
 213 #ifdef CONFIG_PM_SLEEP
 214 static int s3c24xx_dclk_suspend(struct device *dev)
 215 {
 216         struct platform_device *pdev = to_platform_device(dev);
 217         struct s3c24xx_dclk *s3c24xx_dclk = platform_get_drvdata(pdev);
 218
 219         s3c24xx_dclk->reg_save = readl_relaxed(s3c24xx_dclk->base);
 220         return 0;
 221 }
 222
 223 static int s3c24xx_dclk_resume(struct device *dev)
 224 {
 225         struct platform_device *pdev = to_platform_device(dev);
 226         struct s3c24xx_dclk *s3c24xx_dclk = platform_get_drvdata(pdev);
 227
 228         writel_relaxed(s3c24xx_dclk->reg_save, s3c24xx_dclk->base);
 229         return 0;
 230 }
 231 #endif
 232
 233 static SIMPLE_DEV_PM_OPS(s3c24xx_dclk_pm_ops,
 234                          s3c24xx_dclk_suspend, s3c24xx_dclk_resume);
 235
 236 static int s3c24xx_dclk_probe(struct platform_device *pdev)
 237 {
 238         struct s3c24xx_dclk *s3c24xx_dclk;
 239         struct resource *mem;
 240         struct clk **clk_table;
 241         struct s3c24xx_dclk_drv_data *dclk_variant;
 242         int ret, i;
 243
 244         s3c24xx_dclk = devm_kzalloc(&pdev->dev, sizeof(*s3c24xx_dclk),
 245                                     GFP_KERNEL);
 246         if (!s3c24xx_dclk)
 247                 return -ENOMEM;
 248
 249         s3c24xx_dclk->dev = &pdev->dev;
 250         platform_set_drvdata(pdev, s3c24xx_dclk);
 251         spin_lock_init(&s3c24xx_dclk->dclk_lock);
 252
 253         clk_table = devm_kzalloc(&pdev->dev,
 254                                  sizeof(struct clk *) * DCLK_MAX_CLKS,
 255                                  GFP_KERNEL);
 256         if (!clk_table)
 257                 return -ENOMEM;
 258
 259         s3c24xx_dclk->clk_data.clks = clk_table;
 260         s3c24xx_dclk->clk_data.clk_num = DCLK_MAX_CLKS;
 261
 262         mem = platform_get_resource(pdev, IORESOURCE_MEM, 0);
 263         s3c24xx_dclk->base = devm_ioremap_resource(&pdev->dev, mem);
 264         if (IS_ERR(s3c24xx_dclk->base))
 265                 return PTR_ERR(s3c24xx_dclk->base);
 266
 267         dclk_variant = (struct s3c24xx_dclk_drv_data *)
 268                                 platform_get_device_id(pdev)->driver_data;
 269
 270
 271         clk_table[MUX_DCLK0] = clk_register_mux(&pdev->dev, "mux_dclk0",
 272                                 dclk_variant->mux_parent_names,
 273                                 dclk_variant->mux_num_parents, 0,
 274                                 s3c24xx_dclk->base, 1, 1, 0,
 275                                 &s3c24xx_dclk->dclk_lock);
 276         clk_table[MUX_DCLK1] = clk_register_mux(&pdev->dev, "mux_dclk1",
 277                                 dclk_variant->mux_parent_names,
 278                                 dclk_variant->mux_num_parents, 0,
 279                                 s3c24xx_dclk->base, 17, 1, 0,
 280                                 &s3c24xx_dclk->dclk_lock);
 281
 282         clk_table[DIV_DCLK0] = clk_register_divider(&pdev->dev, "div_dclk0",
 283                                 "mux_dclk0", 0, s3c24xx_dclk->base,
 284                                 4, 4, 0, &s3c24xx_dclk->dclk_lock);
 285         clk_table[DIV_DCLK1] = clk_register_divider(&pdev->dev, "div_dclk1",
 286                                 "mux_dclk1", 0, s3c24xx_dclk->base,
 287                                 20, 4, 0, &s3c24xx_dclk->dclk_lock);
 288
 289         clk_table[GATE_DCLK0] = clk_register_gate(&pdev->dev, "gate_dclk0",
 290                                 "div_dclk0", CLK_SET_RATE_PARENT,
 291                                 s3c24xx_dclk->base, 0, 0,
 292                                 &s3c24xx_dclk->dclk_lock);
 293         clk_table[GATE_DCLK1] = clk_register_gate(&pdev->dev, "gate_dclk1",
 294                                 "div_dclk1", CLK_SET_RATE_PARENT,
 295                                 s3c24xx_dclk->base, 16, 0,
 296                                 &s3c24xx_dclk->dclk_lock);
 297
 298         clk_table[MUX_CLKOUT0] = s3c24xx_register_clkout(&pdev->dev,
 299                                 "clkout0", dclk_variant->clkout0_parent_names,
 300                                 dclk_variant->clkout0_num_parents, 4, 7);
 301         clk_table[MUX_CLKOUT1] = s3c24xx_register_clkout(&pdev->dev,
 302                                 "clkout1", dclk_variant->clkout1_parent_names,
 303                                 dclk_variant->clkout1_num_parents, 8, 7);
 304
 305         for (i = 0; i < DCLK_MAX_CLKS; i++)
 306                 if (IS_ERR(clk_table[i])) {
 307                         dev_err(&pdev->dev, "clock %d failed to register\n", i);
 308                         ret = PTR_ERR(clk_table[i]);
 309                         goto err_clk_register;
 310                 }
 311
 312         ret = clk_register_clkdev(clk_table[MUX_DCLK0], "dclk0", NULL);
 313         if (!ret)
 314                 ret = clk_register_clkdev(clk_table[MUX_DCLK1], "dclk1", NULL);
 315         if (!ret)
 316                 ret = clk_register_clkdev(clk_table[MUX_CLKOUT0],
 317                                           "clkout0", NULL);
 318         if (!ret)
 319                 ret = clk_register_clkdev(clk_table[MUX_CLKOUT1],
 320                                           "clkout1", NULL);
 321         if (ret) {
 322                 dev_err(&pdev->dev, "failed to register aliases, %d\n", ret);
 323                 goto err_clk_register;
 324         }
 325
 326         s3c24xx_dclk->dclk0_div_change_nb.notifier_call =
 327                                                 s3c24xx_dclk0_div_notify;
 328
 329         s3c24xx_dclk->dclk1_div_change_nb.notifier_call =
 330                                                 s3c24xx_dclk1_div_notify;
 331
 332         ret = clk_notifier_register(clk_table[DIV_DCLK0],
 333                                     &s3c24xx_dclk->dclk0_div_change_nb);
 334         if (ret)
 335                 goto err_clk_register;
 336
 337         ret = clk_notifier_register(clk_table[DIV_DCLK1],
 338                                     &s3c24xx_dclk->dclk1_div_change_nb);
 339         if (ret)
 340                 goto err_dclk_notify;
 341
 342         return 0;
 343
 344 err_dclk_notify:
 345         clk_notifier_unregister(clk_table[DIV_DCLK0],
 346                                 &s3c24xx_dclk->dclk0_div_change_nb);
 347 err_clk_register:
 348         for (i = 0; i < DCLK_MAX_CLKS; i++)
 349                 if (clk_table[i] && !IS_ERR(clk_table[i]))
 350                         clk_unregister(clk_table[i]);
 351
 352         return ret;
 353 }
 354
 355 static int s3c24xx_dclk_remove(struct platform_device *pdev)
 356 {
 357         struct s3c24xx_dclk *s3c24xx_dclk = platform_get_drvdata(pdev);
 358         struct clk **clk_table = s3c24xx_dclk->clk_data.clks;
 359         int i;
 360
 361         clk_notifier_unregister(clk_table[DIV_DCLK1],
 362                                 &s3c24xx_dclk->dclk1_div_change_nb);
 363         clk_notifier_unregister(clk_table[DIV_DCLK0],
 364                                 &s3c24xx_dclk->dclk0_div_change_nb);
 365
 366         for (i = 0; i < DCLK_MAX_CLKS; i++)
 367                 clk_unregister(clk_table[i]);
 368
 369         return 0;
 370 }
 371
 372 static struct s3c24xx_dclk_drv_data dclk_variants[] = {
 373         [S3C2410] = {
 374                 .clkout0_parent_names = clkout0_s3c2410_p,
 375                 .clkout0_num_parents = ARRAY_SIZE(clkout0_s3c2410_p),
 376                 .clkout1_parent_names = clkout1_s3c2410_p,
 377                 .clkout1_num_parents = ARRAY_SIZE(clkout1_s3c2410_p),
 378                 .mux_parent_names = dclk_s3c2410_p,
 379                 .mux_num_parents = ARRAY_SIZE(dclk_s3c2410_p),
 380         },
 381         [S3C2412] = {
 382                 .clkout0_parent_names = clkout0_s3c2412_p,
 383                 .clkout0_num_parents = ARRAY_SIZE(clkout0_s3c2412_p),
 384                 .clkout1_parent_names = clkout1_s3c2412_p,
 385                 .clkout1_num_parents = ARRAY_SIZE(clkout1_s3c2412_p),
 386                 .mux_parent_names = dclk_s3c2410_p,
 387                 .mux_num_parents = ARRAY_SIZE(dclk_s3c2410_p),
 388         },
 389         [S3C2440] = {
 390                 .clkout0_parent_names = clkout0_s3c2440_p,
 391                 .clkout0_num_parents = ARRAY_SIZE(clkout0_s3c2440_p),
 392                 .clkout1_parent_names = clkout1_s3c2440_p,
 393                 .clkout1_num_parents = ARRAY_SIZE(clkout1_s3c2440_p),
 394                 .mux_parent_names = dclk_s3c2410_p,
 395                 .mux_num_parents = ARRAY_SIZE(dclk_s3c2410_p),
 396         },
 397         [S3C2443] = {
 398                 .clkout0_parent_names = clkout0_s3c2443_p,
 399                 .clkout0_num_parents = ARRAY_SIZE(clkout0_s3c2443_p),
 400                 .clkout1_parent_names = clkout1_s3c2443_p,
 401                 .clkout1_num_parents = ARRAY_SIZE(clkout1_s3c2443_p),
 402                 .mux_parent_names = dclk_s3c2443_p,
 403                 .mux_num_parents = ARRAY_SIZE(dclk_s3c2443_p),
 404         },
 405 };
 406
 407 static struct platform_device_id s3c24xx_dclk_driver_ids[] = {
 408         {
 409                 .name           = "s3c2410-dclk",
 410                 .driver_data    = (kernel_ulong_t)&dclk_variants[S3C2410],
 411         }, {
 412                 .name           = "s3c2412-dclk",
 413                 .driver_data    = (kernel_ulong_t)&dclk_variants[S3C2412],
 414         }, {
 415                 .name           = "s3c2440-dclk",
 416                 .driver_data    = (kernel_ulong_t)&dclk_variants[S3C2440],
 417         }, {
 418                 .name           = "s3c2443-dclk",
 419                 .driver_data    = (kernel_ulong_t)&dclk_variants[S3C2443],
 420         },
 421         { }
 422 };
 423
 424 MODULE_DEVICE_TABLE(platform, s3c24xx_dclk_driver_ids);
 425
 426 static struct platform_driver s3c24xx_dclk_driver = {
 427         .driver = {
 428                 .name           = "s3c24xx-dclk",
 429                 .pm             = &s3c24xx_dclk_pm_ops,
 430         },
 431         .probe = s3c24xx_dclk_probe,
 432         .remove = s3c24xx_dclk_remove,
 433         .id_table = s3c24xx_dclk_driver_ids,
 434 };
 435 module_platform_driver(s3c24xx_dclk_driver);
 436
 437 MODULE_LICENSE("GPL v2");
 438 MODULE_AUTHOR("Heiko Stuebner <heiko@sntech.de>");
 439 MODULE_DESCRIPTION("Driver for the S3C24XX external clock outputs");