linux/drivers/clk/samsung/clk-s3c2410-dclk.c
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   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
  33enum supported_socs {
  34        S3C2410,
  35        S3C2412,
  36        S3C2440,
  37        S3C2443,
  38};
  39
  40struct 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
  53struct 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
  61static 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
  77static 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
  87static 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
  93static 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
 125struct 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
 141static const char *dclk_s3c2410_p[] = { "pclk", "uclk" };
 142static const char *clkout0_s3c2410_p[] = { "mpll", "upll", "fclk", "hclk", "pclk",
 143                             "gate_dclk0" };
 144static const char *clkout1_s3c2410_p[] = { "mpll", "upll", "fclk", "hclk", "pclk",
 145                             "gate_dclk1" };
 146
 147static const char *clkout0_s3c2412_p[] = { "mpll", "upll", "rtc_clkout",
 148                             "hclk", "pclk", "gate_dclk0" };
 149static const char *clkout1_s3c2412_p[] = { "xti", "upll", "fclk", "hclk", "pclk",
 150                             "gate_dclk1" };
 151
 152static const char *clkout0_s3c2440_p[] = { "xti", "upll", "fclk", "hclk", "pclk",
 153                             "gate_dclk0" };
 154static const char *clkout1_s3c2440_p[] = { "mpll", "upll", "rtc_clkout",
 155                             "hclk", "pclk", "gate_dclk1" };
 156
 157static const char *dclk_s3c2443_p[] = { "pclk", "epll" };
 158static const char *clkout0_s3c2443_p[] = { "xti", "epll", "armclk", "hclk", "pclk",
 159                             "gate_dclk0" };
 160static 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
 169static 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
 190static 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
 203static 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
 217static 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
 226static 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
 236static SIMPLE_DEV_PM_OPS(s3c24xx_dclk_pm_ops,
 237                         s3c24xx_dclk_suspend, s3c24xx_dclk_resume);
 238
 239static 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
 347err_dclk_notify:
 348        clk_notifier_unregister(clk_table[DIV_DCLK0],
 349                                &s3c24xx_dclk->dclk0_div_change_nb);
 350err_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
 358static 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
 375static 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
 410static 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
 427MODULE_DEVICE_TABLE(platform, s3c24xx_dclk_driver_ids);
 428
 429static 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};
 439module_platform_driver(s3c24xx_dclk_driver);
 440
 441MODULE_LICENSE("GPL v2");
 442MODULE_AUTHOR("Heiko Stuebner <heiko@sntech.de>");
 443MODULE_DESCRIPTION("Driver for the S3C24XX external clock outputs");
 444