root/drivers/clk/at91/clk-usb.c

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DEFINITIONS

This source file includes following definitions.
  1. at91sam9x5_clk_usb_recalc_rate
  2. at91sam9x5_clk_usb_determine_rate
  3. at91sam9x5_clk_usb_set_parent
  4. at91sam9x5_clk_usb_get_parent
  5. at91sam9x5_clk_usb_set_rate
  6. at91sam9n12_clk_usb_enable
  7. at91sam9n12_clk_usb_disable
  8. at91sam9n12_clk_usb_is_enabled
  9. _at91sam9x5_clk_register_usb
  10. at91sam9x5_clk_register_usb
  11. sam9x60_clk_register_usb
  12. at91sam9n12_clk_register_usb
  13. at91rm9200_clk_usb_recalc_rate
  14. at91rm9200_clk_usb_round_rate
  15. at91rm9200_clk_usb_set_rate
  16. at91rm9200_clk_register_usb

   1 // SPDX-License-Identifier: GPL-2.0-or-later
   2 /*
   3  *  Copyright (C) 2013 Boris BREZILLON <b.brezillon@overkiz.com>
   4  */
   5 
   6 #include <linux/clk-provider.h>
   7 #include <linux/clkdev.h>
   8 #include <linux/clk/at91_pmc.h>
   9 #include <linux/of.h>
  10 #include <linux/mfd/syscon.h>
  11 #include <linux/regmap.h>
  12 
  13 #include "pmc.h"
  14 
  15 #define SAM9X5_USB_DIV_SHIFT    8
  16 #define SAM9X5_USB_MAX_DIV      0xf
  17 
  18 #define RM9200_USB_DIV_SHIFT    28
  19 #define RM9200_USB_DIV_TAB_SIZE 4
  20 
  21 #define SAM9X5_USBS_MASK        GENMASK(0, 0)
  22 #define SAM9X60_USBS_MASK       GENMASK(1, 0)
  23 
  24 struct at91sam9x5_clk_usb {
  25         struct clk_hw hw;
  26         struct regmap *regmap;
  27         u32 usbs_mask;
  28 };
  29 
  30 #define to_at91sam9x5_clk_usb(hw) \
  31         container_of(hw, struct at91sam9x5_clk_usb, hw)
  32 
  33 struct at91rm9200_clk_usb {
  34         struct clk_hw hw;
  35         struct regmap *regmap;
  36         u32 divisors[4];
  37 };
  38 
  39 #define to_at91rm9200_clk_usb(hw) \
  40         container_of(hw, struct at91rm9200_clk_usb, hw)
  41 
  42 static unsigned long at91sam9x5_clk_usb_recalc_rate(struct clk_hw *hw,
  43                                                     unsigned long parent_rate)
  44 {
  45         struct at91sam9x5_clk_usb *usb = to_at91sam9x5_clk_usb(hw);
  46         unsigned int usbr;
  47         u8 usbdiv;
  48 
  49         regmap_read(usb->regmap, AT91_PMC_USB, &usbr);
  50         usbdiv = (usbr & AT91_PMC_OHCIUSBDIV) >> SAM9X5_USB_DIV_SHIFT;
  51 
  52         return DIV_ROUND_CLOSEST(parent_rate, (usbdiv + 1));
  53 }
  54 
  55 static int at91sam9x5_clk_usb_determine_rate(struct clk_hw *hw,
  56                                              struct clk_rate_request *req)
  57 {
  58         struct clk_hw *parent;
  59         long best_rate = -EINVAL;
  60         unsigned long tmp_rate;
  61         int best_diff = -1;
  62         int tmp_diff;
  63         int i;
  64 
  65         for (i = 0; i < clk_hw_get_num_parents(hw); i++) {
  66                 int div;
  67 
  68                 parent = clk_hw_get_parent_by_index(hw, i);
  69                 if (!parent)
  70                         continue;
  71 
  72                 for (div = 1; div < SAM9X5_USB_MAX_DIV + 2; div++) {
  73                         unsigned long tmp_parent_rate;
  74 
  75                         tmp_parent_rate = req->rate * div;
  76                         tmp_parent_rate = clk_hw_round_rate(parent,
  77                                                            tmp_parent_rate);
  78                         if (!tmp_parent_rate)
  79                                 continue;
  80 
  81                         tmp_rate = DIV_ROUND_CLOSEST(tmp_parent_rate, div);
  82                         if (tmp_rate < req->rate)
  83                                 tmp_diff = req->rate - tmp_rate;
  84                         else
  85                                 tmp_diff = tmp_rate - req->rate;
  86 
  87                         if (best_diff < 0 || best_diff > tmp_diff) {
  88                                 best_rate = tmp_rate;
  89                                 best_diff = tmp_diff;
  90                                 req->best_parent_rate = tmp_parent_rate;
  91                                 req->best_parent_hw = parent;
  92                         }
  93 
  94                         if (!best_diff || tmp_rate < req->rate)
  95                                 break;
  96                 }
  97 
  98                 if (!best_diff)
  99                         break;
 100         }
 101 
 102         if (best_rate < 0)
 103                 return best_rate;
 104 
 105         req->rate = best_rate;
 106         return 0;
 107 }
 108 
 109 static int at91sam9x5_clk_usb_set_parent(struct clk_hw *hw, u8 index)
 110 {
 111         struct at91sam9x5_clk_usb *usb = to_at91sam9x5_clk_usb(hw);
 112 
 113         if (index > 1)
 114                 return -EINVAL;
 115 
 116         regmap_update_bits(usb->regmap, AT91_PMC_USB, usb->usbs_mask, index);
 117 
 118         return 0;
 119 }
 120 
 121 static u8 at91sam9x5_clk_usb_get_parent(struct clk_hw *hw)
 122 {
 123         struct at91sam9x5_clk_usb *usb = to_at91sam9x5_clk_usb(hw);
 124         unsigned int usbr;
 125 
 126         regmap_read(usb->regmap, AT91_PMC_USB, &usbr);
 127 
 128         return usbr & usb->usbs_mask;
 129 }
 130 
 131 static int at91sam9x5_clk_usb_set_rate(struct clk_hw *hw, unsigned long rate,
 132                                        unsigned long parent_rate)
 133 {
 134         struct at91sam9x5_clk_usb *usb = to_at91sam9x5_clk_usb(hw);
 135         unsigned long div;
 136 
 137         if (!rate)
 138                 return -EINVAL;
 139 
 140         div = DIV_ROUND_CLOSEST(parent_rate, rate);
 141         if (div > SAM9X5_USB_MAX_DIV + 1 || !div)
 142                 return -EINVAL;
 143 
 144         regmap_update_bits(usb->regmap, AT91_PMC_USB, AT91_PMC_OHCIUSBDIV,
 145                            (div - 1) << SAM9X5_USB_DIV_SHIFT);
 146 
 147         return 0;
 148 }
 149 
 150 static const struct clk_ops at91sam9x5_usb_ops = {
 151         .recalc_rate = at91sam9x5_clk_usb_recalc_rate,
 152         .determine_rate = at91sam9x5_clk_usb_determine_rate,
 153         .get_parent = at91sam9x5_clk_usb_get_parent,
 154         .set_parent = at91sam9x5_clk_usb_set_parent,
 155         .set_rate = at91sam9x5_clk_usb_set_rate,
 156 };
 157 
 158 static int at91sam9n12_clk_usb_enable(struct clk_hw *hw)
 159 {
 160         struct at91sam9x5_clk_usb *usb = to_at91sam9x5_clk_usb(hw);
 161 
 162         regmap_update_bits(usb->regmap, AT91_PMC_USB, AT91_PMC_USBS,
 163                            AT91_PMC_USBS);
 164 
 165         return 0;
 166 }
 167 
 168 static void at91sam9n12_clk_usb_disable(struct clk_hw *hw)
 169 {
 170         struct at91sam9x5_clk_usb *usb = to_at91sam9x5_clk_usb(hw);
 171 
 172         regmap_update_bits(usb->regmap, AT91_PMC_USB, AT91_PMC_USBS, 0);
 173 }
 174 
 175 static int at91sam9n12_clk_usb_is_enabled(struct clk_hw *hw)
 176 {
 177         struct at91sam9x5_clk_usb *usb = to_at91sam9x5_clk_usb(hw);
 178         unsigned int usbr;
 179 
 180         regmap_read(usb->regmap, AT91_PMC_USB, &usbr);
 181 
 182         return usbr & AT91_PMC_USBS;
 183 }
 184 
 185 static const struct clk_ops at91sam9n12_usb_ops = {
 186         .enable = at91sam9n12_clk_usb_enable,
 187         .disable = at91sam9n12_clk_usb_disable,
 188         .is_enabled = at91sam9n12_clk_usb_is_enabled,
 189         .recalc_rate = at91sam9x5_clk_usb_recalc_rate,
 190         .determine_rate = at91sam9x5_clk_usb_determine_rate,
 191         .set_rate = at91sam9x5_clk_usb_set_rate,
 192 };
 193 
 194 static struct clk_hw * __init
 195 _at91sam9x5_clk_register_usb(struct regmap *regmap, const char *name,
 196                              const char **parent_names, u8 num_parents,
 197                              u32 usbs_mask)
 198 {
 199         struct at91sam9x5_clk_usb *usb;
 200         struct clk_hw *hw;
 201         struct clk_init_data init;
 202         int ret;
 203 
 204         usb = kzalloc(sizeof(*usb), GFP_KERNEL);
 205         if (!usb)
 206                 return ERR_PTR(-ENOMEM);
 207 
 208         init.name = name;
 209         init.ops = &at91sam9x5_usb_ops;
 210         init.parent_names = parent_names;
 211         init.num_parents = num_parents;
 212         init.flags = CLK_SET_RATE_GATE | CLK_SET_PARENT_GATE |
 213                      CLK_SET_RATE_PARENT;
 214 
 215         usb->hw.init = &init;
 216         usb->regmap = regmap;
 217         usb->usbs_mask = usbs_mask;
 218 
 219         hw = &usb->hw;
 220         ret = clk_hw_register(NULL, &usb->hw);
 221         if (ret) {
 222                 kfree(usb);
 223                 hw = ERR_PTR(ret);
 224         }
 225 
 226         return hw;
 227 }
 228 
 229 struct clk_hw * __init
 230 at91sam9x5_clk_register_usb(struct regmap *regmap, const char *name,
 231                             const char **parent_names, u8 num_parents)
 232 {
 233         return _at91sam9x5_clk_register_usb(regmap, name, parent_names,
 234                                             num_parents, SAM9X5_USBS_MASK);
 235 }
 236 
 237 struct clk_hw * __init
 238 sam9x60_clk_register_usb(struct regmap *regmap, const char *name,
 239                          const char **parent_names, u8 num_parents)
 240 {
 241         return _at91sam9x5_clk_register_usb(regmap, name, parent_names,
 242                                             num_parents, SAM9X60_USBS_MASK);
 243 }
 244 
 245 struct clk_hw * __init
 246 at91sam9n12_clk_register_usb(struct regmap *regmap, const char *name,
 247                              const char *parent_name)
 248 {
 249         struct at91sam9x5_clk_usb *usb;
 250         struct clk_hw *hw;
 251         struct clk_init_data init;
 252         int ret;
 253 
 254         usb = kzalloc(sizeof(*usb), GFP_KERNEL);
 255         if (!usb)
 256                 return ERR_PTR(-ENOMEM);
 257 
 258         init.name = name;
 259         init.ops = &at91sam9n12_usb_ops;
 260         init.parent_names = &parent_name;
 261         init.num_parents = 1;
 262         init.flags = CLK_SET_RATE_GATE | CLK_SET_RATE_PARENT;
 263 
 264         usb->hw.init = &init;
 265         usb->regmap = regmap;
 266 
 267         hw = &usb->hw;
 268         ret = clk_hw_register(NULL, &usb->hw);
 269         if (ret) {
 270                 kfree(usb);
 271                 hw = ERR_PTR(ret);
 272         }
 273 
 274         return hw;
 275 }
 276 
 277 static unsigned long at91rm9200_clk_usb_recalc_rate(struct clk_hw *hw,
 278                                                     unsigned long parent_rate)
 279 {
 280         struct at91rm9200_clk_usb *usb = to_at91rm9200_clk_usb(hw);
 281         unsigned int pllbr;
 282         u8 usbdiv;
 283 
 284         regmap_read(usb->regmap, AT91_CKGR_PLLBR, &pllbr);
 285 
 286         usbdiv = (pllbr & AT91_PMC_USBDIV) >> RM9200_USB_DIV_SHIFT;
 287         if (usb->divisors[usbdiv])
 288                 return parent_rate / usb->divisors[usbdiv];
 289 
 290         return 0;
 291 }
 292 
 293 static long at91rm9200_clk_usb_round_rate(struct clk_hw *hw, unsigned long rate,
 294                                           unsigned long *parent_rate)
 295 {
 296         struct at91rm9200_clk_usb *usb = to_at91rm9200_clk_usb(hw);
 297         struct clk_hw *parent = clk_hw_get_parent(hw);
 298         unsigned long bestrate = 0;
 299         int bestdiff = -1;
 300         unsigned long tmprate;
 301         int tmpdiff;
 302         int i = 0;
 303 
 304         for (i = 0; i < RM9200_USB_DIV_TAB_SIZE; i++) {
 305                 unsigned long tmp_parent_rate;
 306 
 307                 if (!usb->divisors[i])
 308                         continue;
 309 
 310                 tmp_parent_rate = rate * usb->divisors[i];
 311                 tmp_parent_rate = clk_hw_round_rate(parent, tmp_parent_rate);
 312                 tmprate = DIV_ROUND_CLOSEST(tmp_parent_rate, usb->divisors[i]);
 313                 if (tmprate < rate)
 314                         tmpdiff = rate - tmprate;
 315                 else
 316                         tmpdiff = tmprate - rate;
 317 
 318                 if (bestdiff < 0 || bestdiff > tmpdiff) {
 319                         bestrate = tmprate;
 320                         bestdiff = tmpdiff;
 321                         *parent_rate = tmp_parent_rate;
 322                 }
 323 
 324                 if (!bestdiff)
 325                         break;
 326         }
 327 
 328         return bestrate;
 329 }
 330 
 331 static int at91rm9200_clk_usb_set_rate(struct clk_hw *hw, unsigned long rate,
 332                                        unsigned long parent_rate)
 333 {
 334         int i;
 335         struct at91rm9200_clk_usb *usb = to_at91rm9200_clk_usb(hw);
 336         unsigned long div;
 337 
 338         if (!rate)
 339                 return -EINVAL;
 340 
 341         div = DIV_ROUND_CLOSEST(parent_rate, rate);
 342 
 343         for (i = 0; i < RM9200_USB_DIV_TAB_SIZE; i++) {
 344                 if (usb->divisors[i] == div) {
 345                         regmap_update_bits(usb->regmap, AT91_CKGR_PLLBR,
 346                                            AT91_PMC_USBDIV,
 347                                            i << RM9200_USB_DIV_SHIFT);
 348 
 349                         return 0;
 350                 }
 351         }
 352 
 353         return -EINVAL;
 354 }
 355 
 356 static const struct clk_ops at91rm9200_usb_ops = {
 357         .recalc_rate = at91rm9200_clk_usb_recalc_rate,
 358         .round_rate = at91rm9200_clk_usb_round_rate,
 359         .set_rate = at91rm9200_clk_usb_set_rate,
 360 };
 361 
 362 struct clk_hw * __init
 363 at91rm9200_clk_register_usb(struct regmap *regmap, const char *name,
 364                             const char *parent_name, const u32 *divisors)
 365 {
 366         struct at91rm9200_clk_usb *usb;
 367         struct clk_hw *hw;
 368         struct clk_init_data init;
 369         int ret;
 370 
 371         usb = kzalloc(sizeof(*usb), GFP_KERNEL);
 372         if (!usb)
 373                 return ERR_PTR(-ENOMEM);
 374 
 375         init.name = name;
 376         init.ops = &at91rm9200_usb_ops;
 377         init.parent_names = &parent_name;
 378         init.num_parents = 1;
 379         init.flags = CLK_SET_RATE_PARENT;
 380 
 381         usb->hw.init = &init;
 382         usb->regmap = regmap;
 383         memcpy(usb->divisors, divisors, sizeof(usb->divisors));
 384 
 385         hw = &usb->hw;
 386         ret = clk_hw_register(NULL, &usb->hw);
 387         if (ret) {
 388                 kfree(usb);
 389                 hw = ERR_PTR(ret);
 390         }
 391 
 392         return hw;
 393 }

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