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/clkdev.h>
  12 #include <linux/slab.h>
  13 #include <linux/clk.h>
  14 #include <linux/clk-provider.h>
  15 #include <linux/platform_device.h>
  16 #include <linux/module.h>
  17 #include "clk.h"
  18
  19 /* legacy access to misccr, until dt conversion is finished */
  20 #include <mach/hardware.h>
  21 #include <mach/regs-gpio.h>
  22
  23 #define MUX_DCLK0       0
  24 #define MUX_DCLK1       1
  25 #define DIV_DCLK0       2
  26 #define DIV_DCLK1       3
  27 #define GATE_DCLK0      4
  28 #define GATE_DCLK1      5
  29 #define MUX_CLKOUT0     6
  30 #define MUX_CLKOUT1     7
  31 #define DCLK_MAX_CLKS   (MUX_CLKOUT1 + 1)
  32
  33 enum supported_socs {
  34         S3C2410,
  35         S3C2412,
  36         S3C2440,
  37         S3C2443,
  38 };
  39
  40 struct s3c24xx_dclk_drv_data {
  41         const char **clkout0_parent_names;
  42         int clkout0_num_parents;
  43         const char **clkout1_parent_names;
  44         int clkout1_num_parents;
  45         const char **mux_parent_names;
  46         int mux_num_parents;
  47 };
  48
  49 /*
  50  * Clock for output-parent selection in misccr
  51  */
  52
  53 struct s3c24xx_clkout {
  54         struct clk_hw           hw;
  55         u32                     mask;
  56         u8                      shift;
  57 };
  58
  59 #define to_s3c24xx_clkout(_hw) container_of(_hw, struct s3c24xx_clkout, hw)
  60
  61 static u8 s3c24xx_clkout_get_parent(struct clk_hw *hw)
  62 {
  63         struct s3c24xx_clkout *clkout = to_s3c24xx_clkout(hw);
  64         int num_parents = clk_hw_get_num_parents(hw);
  65         u32 val;
  66
  67         val = readl_relaxed(S3C24XX_MISCCR) >> clkout->shift;
  68         val >>= clkout->shift;
  69         val &= clkout->mask;
  70
  71         if (val >= num_parents)
  72                 return -EINVAL;
  73
  74         return val;
  75 }
  76
  77 static int s3c24xx_clkout_set_parent(struct clk_hw *hw, u8 index)
  78 {
  79         struct s3c24xx_clkout *clkout = to_s3c24xx_clkout(hw);
  80
  81         s3c2410_modify_misccr((clkout->mask << clkout->shift),
  82                               (index << clkout->shift));
  83
  84         return 0;
  85 }
  86
  87 static const struct clk_ops s3c24xx_clkout_ops = {
  88         .get_parent = s3c24xx_clkout_get_parent,
  89         .set_parent = s3c24xx_clkout_set_parent,
  90         .determine_rate = __clk_mux_determine_rate,
  91 };
  92
  93 static struct clk *s3c24xx_register_clkout(struct device *dev, const char *name,
  94                 const char **parent_names, u8 num_parents,
  95                 u8 shift, u32 mask)
  96 {
  97         struct s3c24xx_clkout *clkout;
  98         struct clk *clk;
  99         struct clk_init_data init;
 100
 101         /* allocate the clkout */
 102         clkout = kzalloc(sizeof(*clkout), GFP_KERNEL);
 103         if (!clkout)
 104                 return ERR_PTR(-ENOMEM);
 105
 106         init.name = name;
 107         init.ops = &s3c24xx_clkout_ops;
 108         init.flags = CLK_IS_BASIC;
 109         init.parent_names = parent_names;
 110         init.num_parents = num_parents;
 111
 112         clkout->shift = shift;
 113         clkout->mask = mask;
 114         clkout->hw.init = &init;
 115
 116         clk = clk_register(dev, &clkout->hw);
 117
 118         return clk;
 119 }
 120
 121 /*
 122  * dclk and clkout init
 123  */
 124
 125 struct s3c24xx_dclk {
 126         struct device *dev;
 127         void __iomem *base;
 128         struct clk_onecell_data clk_data;
 129         struct notifier_block dclk0_div_change_nb;
 130         struct notifier_block dclk1_div_change_nb;
 131         spinlock_t dclk_lock;
 132         unsigned long reg_save;
 133 };
 134
 135 #define to_s3c24xx_dclk0(x) \
 136                 container_of(x, struct s3c24xx_dclk, dclk0_div_change_nb)
 137
 138 #define to_s3c24xx_dclk1(x) \
 139                 container_of(x, struct s3c24xx_dclk, dclk1_div_change_nb)
 140
 141 static const char *dclk_s3c2410_p[] = { "pclk", "uclk" };
 142 static const char *clkout0_s3c2410_p[] = { "mpll", "upll", "fclk", "hclk", "pclk",
 143                              "gate_dclk0" };
 144 static const char *clkout1_s3c2410_p[] = { "mpll", "upll", "fclk", "hclk", "pclk",
 145                              "gate_dclk1" };
 146
 147 static const char *clkout0_s3c2412_p[] = { "mpll", "upll", "rtc_clkout",
 148                              "hclk", "pclk", "gate_dclk0" };
 149 static const char *clkout1_s3c2412_p[] = { "xti", "upll", "fclk", "hclk", "pclk",
 150                              "gate_dclk1" };
 151
 152 static const char *clkout0_s3c2440_p[] = { "xti", "upll", "fclk", "hclk", "pclk",
 153                              "gate_dclk0" };
 154 static const char *clkout1_s3c2440_p[] = { "mpll", "upll", "rtc_clkout",
 155                              "hclk", "pclk", "gate_dclk1" };
 156
 157 static const char *dclk_s3c2443_p[] = { "pclk", "epll" };
 158 static const char *clkout0_s3c2443_p[] = { "xti", "epll", "armclk", "hclk", "pclk",
 159                              "gate_dclk0" };
 160 static const char *clkout1_s3c2443_p[] = { "dummy", "epll", "rtc_clkout",
 161                              "hclk", "pclk", "gate_dclk1" };
 162
 163 #define DCLKCON_DCLK_DIV_MASK           0xf
 164 #define DCLKCON_DCLK0_DIV_SHIFT         4
 165 #define DCLKCON_DCLK0_CMP_SHIFT         8
 166 #define DCLKCON_DCLK1_DIV_SHIFT         20
 167 #define DCLKCON_DCLK1_CMP_SHIFT         24
 168
 169 static void s3c24xx_dclk_update_cmp(struct s3c24xx_dclk *s3c24xx_dclk,
 170                                     int div_shift, int cmp_shift)
 171 {
 172         unsigned long flags = 0;
 173         u32 dclk_con, div, cmp;
 174
 175         spin_lock_irqsave(&s3c24xx_dclk->dclk_lock, flags);
 176
 177         dclk_con = readl_relaxed(s3c24xx_dclk->base);
 178
 179         div = ((dclk_con >> div_shift) & DCLKCON_DCLK_DIV_MASK) + 1;
 180         cmp = ((div + 1) / 2) - 1;
 181
 182         dclk_con &= ~(DCLKCON_DCLK_DIV_MASK << cmp_shift);
 183         dclk_con |= (cmp << cmp_shift);
 184
 185         writel_relaxed(dclk_con, s3c24xx_dclk->base);
 186
 187         spin_unlock_irqrestore(&s3c24xx_dclk->dclk_lock, flags);
 188 }
 189
 190 static int s3c24xx_dclk0_div_notify(struct notifier_block *nb,
 191                                unsigned long event, void *data)
 192 {
 193         struct s3c24xx_dclk *s3c24xx_dclk = to_s3c24xx_dclk0(nb);
 194
 195         if (event == POST_RATE_CHANGE) {
 196                 s3c24xx_dclk_update_cmp(s3c24xx_dclk,
 197                         DCLKCON_DCLK0_DIV_SHIFT, DCLKCON_DCLK0_CMP_SHIFT);
 198         }
 199
 200         return NOTIFY_DONE;
 201 }
 202
 203 static int s3c24xx_dclk1_div_notify(struct notifier_block *nb,
 204                                unsigned long event, void *data)
 205 {
 206         struct s3c24xx_dclk *s3c24xx_dclk = to_s3c24xx_dclk1(nb);
 207
 208         if (event == POST_RATE_CHANGE) {
 209                 s3c24xx_dclk_update_cmp(s3c24xx_dclk,
 210                         DCLKCON_DCLK1_DIV_SHIFT, DCLKCON_DCLK1_CMP_SHIFT);
 211         }
 212
 213         return NOTIFY_DONE;
 214 }
 215
 216 #ifdef CONFIG_PM_SLEEP
 217 static int s3c24xx_dclk_suspend(struct device *dev)
 218 {
 219         struct platform_device *pdev = to_platform_device(dev);
 220         struct s3c24xx_dclk *s3c24xx_dclk = platform_get_drvdata(pdev);
 221
 222         s3c24xx_dclk->reg_save = readl_relaxed(s3c24xx_dclk->base);
 223         return 0;
 224 }
 225
 226 static int s3c24xx_dclk_resume(struct device *dev)
 227 {
 228         struct platform_device *pdev = to_platform_device(dev);
 229         struct s3c24xx_dclk *s3c24xx_dclk = platform_get_drvdata(pdev);
 230
 231         writel_relaxed(s3c24xx_dclk->reg_save, s3c24xx_dclk->base);
 232         return 0;
 233 }
 234 #endif
 235
 236 static SIMPLE_DEV_PM_OPS(s3c24xx_dclk_pm_ops,
 237                          s3c24xx_dclk_suspend, s3c24xx_dclk_resume);
 238
 239 static int s3c24xx_dclk_probe(struct platform_device *pdev)
 240 {
 241         struct s3c24xx_dclk *s3c24xx_dclk;
 242         struct resource *mem;
 243         struct clk **clk_table;
 244         struct s3c24xx_dclk_drv_data *dclk_variant;
 245         int ret, i;
 246
 247         s3c24xx_dclk = devm_kzalloc(&pdev->dev, sizeof(*s3c24xx_dclk),
 248                                     GFP_KERNEL);
 249         if (!s3c24xx_dclk)
 250                 return -ENOMEM;
 251
 252         s3c24xx_dclk->dev = &pdev->dev;
 253         platform_set_drvdata(pdev, s3c24xx_dclk);
 254         spin_lock_init(&s3c24xx_dclk->dclk_lock);
 255
 256         clk_table = devm_kzalloc(&pdev->dev,
 257                                  sizeof(struct clk *) * DCLK_MAX_CLKS,
 258                                  GFP_KERNEL);
 259         if (!clk_table)
 260                 return -ENOMEM;
 261
 262         s3c24xx_dclk->clk_data.clks = clk_table;
 263         s3c24xx_dclk->clk_data.clk_num = DCLK_MAX_CLKS;
 264
 265         mem = platform_get_resource(pdev, IORESOURCE_MEM, 0);
 266         s3c24xx_dclk->base = devm_ioremap_resource(&pdev->dev, mem);
 267         if (IS_ERR(s3c24xx_dclk->base))
 268                 return PTR_ERR(s3c24xx_dclk->base);
 269
 270         dclk_variant = (struct s3c24xx_dclk_drv_data *)
 271                                 platform_get_device_id(pdev)->driver_data;
 272
 273
 274         clk_table[MUX_DCLK0] = clk_register_mux(&pdev->dev, "mux_dclk0",
 275                                 dclk_variant->mux_parent_names,
 276                                 dclk_variant->mux_num_parents, 0,
 277                                 s3c24xx_dclk->base, 1, 1, 0,
 278                                 &s3c24xx_dclk->dclk_lock);
 279         clk_table[MUX_DCLK1] = clk_register_mux(&pdev->dev, "mux_dclk1",
 280                                 dclk_variant->mux_parent_names,
 281                                 dclk_variant->mux_num_parents, 0,
 282                                 s3c24xx_dclk->base, 17, 1, 0,
 283                                 &s3c24xx_dclk->dclk_lock);
 284
 285         clk_table[DIV_DCLK0] = clk_register_divider(&pdev->dev, "div_dclk0",
 286                                 "mux_dclk0", 0, s3c24xx_dclk->base,
 287                                 4, 4, 0, &s3c24xx_dclk->dclk_lock);
 288         clk_table[DIV_DCLK1] = clk_register_divider(&pdev->dev, "div_dclk1",
 289                                 "mux_dclk1", 0, s3c24xx_dclk->base,
 290                                 20, 4, 0, &s3c24xx_dclk->dclk_lock);
 291
 292         clk_table[GATE_DCLK0] = clk_register_gate(&pdev->dev, "gate_dclk0",
 293                                 "div_dclk0", CLK_SET_RATE_PARENT,
 294                                 s3c24xx_dclk->base, 0, 0,
 295                                 &s3c24xx_dclk->dclk_lock);
 296         clk_table[GATE_DCLK1] = clk_register_gate(&pdev->dev, "gate_dclk1",
 297                                 "div_dclk1", CLK_SET_RATE_PARENT,
 298                                 s3c24xx_dclk->base, 16, 0,
 299                                 &s3c24xx_dclk->dclk_lock);
 300
 301         clk_table[MUX_CLKOUT0] = s3c24xx_register_clkout(&pdev->dev,
 302                                 "clkout0", dclk_variant->clkout0_parent_names,
 303                                 dclk_variant->clkout0_num_parents, 4, 7);
 304         clk_table[MUX_CLKOUT1] = s3c24xx_register_clkout(&pdev->dev,
 305                                 "clkout1", dclk_variant->clkout1_parent_names,
 306                                 dclk_variant->clkout1_num_parents, 8, 7);
 307
 308         for (i = 0; i < DCLK_MAX_CLKS; i++)
 309                 if (IS_ERR(clk_table[i])) {
 310                         dev_err(&pdev->dev, "clock %d failed to register\n", i);
 311                         ret = PTR_ERR(clk_table[i]);
 312                         goto err_clk_register;
 313                 }
 314
 315         ret = clk_register_clkdev(clk_table[MUX_DCLK0], "dclk0", NULL);
 316         if (!ret)
 317                 ret = clk_register_clkdev(clk_table[MUX_DCLK1], "dclk1", NULL);
 318         if (!ret)
 319                 ret = clk_register_clkdev(clk_table[MUX_CLKOUT0],
 320                                           "clkout0", NULL);
 321         if (!ret)
 322                 ret = clk_register_clkdev(clk_table[MUX_CLKOUT1],
 323                                           "clkout1", NULL);
 324         if (ret) {
 325                 dev_err(&pdev->dev, "failed to register aliases, %d\n", ret);
 326                 goto err_clk_register;
 327         }
 328
 329         s3c24xx_dclk->dclk0_div_change_nb.notifier_call =
 330                                                 s3c24xx_dclk0_div_notify;
 331
 332         s3c24xx_dclk->dclk1_div_change_nb.notifier_call =
 333                                                 s3c24xx_dclk1_div_notify;
 334
 335         ret = clk_notifier_register(clk_table[DIV_DCLK0],
 336                                     &s3c24xx_dclk->dclk0_div_change_nb);
 337         if (ret)
 338                 goto err_clk_register;
 339
 340         ret = clk_notifier_register(clk_table[DIV_DCLK1],
 341                                     &s3c24xx_dclk->dclk1_div_change_nb);
 342         if (ret)
 343                 goto err_dclk_notify;
 344
 345         return 0;
 346
 347 err_dclk_notify:
 348         clk_notifier_unregister(clk_table[DIV_DCLK0],
 349                                 &s3c24xx_dclk->dclk0_div_change_nb);
 350 err_clk_register:
 351         for (i = 0; i < DCLK_MAX_CLKS; i++)
 352                 if (clk_table[i] && !IS_ERR(clk_table[i]))
 353                         clk_unregister(clk_table[i]);
 354
 355         return ret;
 356 }
 357
 358 static int s3c24xx_dclk_remove(struct platform_device *pdev)
 359 {
 360         struct s3c24xx_dclk *s3c24xx_dclk = platform_get_drvdata(pdev);
 361         struct clk **clk_table = s3c24xx_dclk->clk_data.clks;
 362         int i;
 363
 364         clk_notifier_unregister(clk_table[DIV_DCLK1],
 365                                 &s3c24xx_dclk->dclk1_div_change_nb);
 366         clk_notifier_unregister(clk_table[DIV_DCLK0],
 367                                 &s3c24xx_dclk->dclk0_div_change_nb);
 368
 369         for (i = 0; i < DCLK_MAX_CLKS; i++)
 370                 clk_unregister(clk_table[i]);
 371
 372         return 0;
 373 }
 374
 375 static struct s3c24xx_dclk_drv_data dclk_variants[] = {
 376         [S3C2410] = {
 377                 .clkout0_parent_names = clkout0_s3c2410_p,
 378                 .clkout0_num_parents = ARRAY_SIZE(clkout0_s3c2410_p),
 379                 .clkout1_parent_names = clkout1_s3c2410_p,
 380                 .clkout1_num_parents = ARRAY_SIZE(clkout1_s3c2410_p),
 381                 .mux_parent_names = dclk_s3c2410_p,
 382                 .mux_num_parents = ARRAY_SIZE(dclk_s3c2410_p),
 383         },
 384         [S3C2412] = {
 385                 .clkout0_parent_names = clkout0_s3c2412_p,
 386                 .clkout0_num_parents = ARRAY_SIZE(clkout0_s3c2412_p),
 387                 .clkout1_parent_names = clkout1_s3c2412_p,
 388                 .clkout1_num_parents = ARRAY_SIZE(clkout1_s3c2412_p),
 389                 .mux_parent_names = dclk_s3c2410_p,
 390                 .mux_num_parents = ARRAY_SIZE(dclk_s3c2410_p),
 391         },
 392         [S3C2440] = {
 393                 .clkout0_parent_names = clkout0_s3c2440_p,
 394                 .clkout0_num_parents = ARRAY_SIZE(clkout0_s3c2440_p),
 395                 .clkout1_parent_names = clkout1_s3c2440_p,
 396                 .clkout1_num_parents = ARRAY_SIZE(clkout1_s3c2440_p),
 397                 .mux_parent_names = dclk_s3c2410_p,
 398                 .mux_num_parents = ARRAY_SIZE(dclk_s3c2410_p),
 399         },
 400         [S3C2443] = {
 401                 .clkout0_parent_names = clkout0_s3c2443_p,
 402                 .clkout0_num_parents = ARRAY_SIZE(clkout0_s3c2443_p),
 403                 .clkout1_parent_names = clkout1_s3c2443_p,
 404                 .clkout1_num_parents = ARRAY_SIZE(clkout1_s3c2443_p),
 405                 .mux_parent_names = dclk_s3c2443_p,
 406                 .mux_num_parents = ARRAY_SIZE(dclk_s3c2443_p),
 407         },
 408 };
 409
 410 static const struct platform_device_id s3c24xx_dclk_driver_ids[] = {
 411         {
 412                 .name           = "s3c2410-dclk",
 413                 .driver_data    = (kernel_ulong_t)&dclk_variants[S3C2410],
 414         }, {
 415                 .name           = "s3c2412-dclk",
 416                 .driver_data    = (kernel_ulong_t)&dclk_variants[S3C2412],
 417         }, {
 418                 .name           = "s3c2440-dclk",
 419                 .driver_data    = (kernel_ulong_t)&dclk_variants[S3C2440],
 420         }, {
 421                 .name           = "s3c2443-dclk",
 422                 .driver_data    = (kernel_ulong_t)&dclk_variants[S3C2443],
 423         },
 424         { }
 425 };
 426
 427 MODULE_DEVICE_TABLE(platform, s3c24xx_dclk_driver_ids);
 428
 429 static struct platform_driver s3c24xx_dclk_driver = {
 430         .driver = {
 431                 .name                   = "s3c24xx-dclk",
 432                 .pm                     = &s3c24xx_dclk_pm_ops,
 433                 .suppress_bind_attrs    = true,
 434         },
 435         .probe = s3c24xx_dclk_probe,
 436         .remove = s3c24xx_dclk_remove,
 437         .id_table = s3c24xx_dclk_driver_ids,
 438 };
 439 module_platform_driver(s3c24xx_dclk_driver);
 440
 441 MODULE_LICENSE("GPL v2");
 442 MODULE_AUTHOR("Heiko Stuebner <heiko@sntech.de>");
 443 MODULE_DESCRIPTION("Driver for the S3C24XX external clock outputs");