Mike Turquette | 9d9f78e | 2012-03-15 23:11:20 -0700 | [diff] [blame] | 1 | /* |
| 2 | * Copyright (C) 2011 Sascha Hauer, Pengutronix <s.hauer@pengutronix.de> |
| 3 | * Copyright (C) 2011 Richard Zhao, Linaro <richard.zhao@linaro.org> |
| 4 | * Copyright (C) 2011-2012 Mike Turquette, Linaro Ltd <mturquette@linaro.org> |
| 5 | * |
| 6 | * This program is free software; you can redistribute it and/or modify |
| 7 | * it under the terms of the GNU General Public License version 2 as |
| 8 | * published by the Free Software Foundation. |
| 9 | * |
| 10 | * Adjustable divider clock implementation |
| 11 | */ |
| 12 | |
| 13 | #include <linux/clk-provider.h> |
| 14 | #include <linux/module.h> |
| 15 | #include <linux/slab.h> |
| 16 | #include <linux/io.h> |
| 17 | #include <linux/err.h> |
| 18 | #include <linux/string.h> |
James Hogan | 1a3cd18 | 2013-01-15 10:28:05 +0000 | [diff] [blame] | 19 | #include <linux/log2.h> |
Mike Turquette | 9d9f78e | 2012-03-15 23:11:20 -0700 | [diff] [blame] | 20 | |
| 21 | /* |
| 22 | * DOC: basic adjustable divider clock that cannot gate |
| 23 | * |
| 24 | * Traits of this clock: |
| 25 | * prepare - clk_prepare only ensures that parents are prepared |
| 26 | * enable - clk_enable only ensures that parents are enabled |
Tomi Valkeinen | b11d282 | 2014-02-13 12:03:59 +0200 | [diff] [blame] | 27 | * rate - rate is adjustable. clk->rate = DIV_ROUND_UP(parent->rate / divisor) |
Mike Turquette | 9d9f78e | 2012-03-15 23:11:20 -0700 | [diff] [blame] | 28 | * parent - fixed parent. No clk_set_parent support |
| 29 | */ |
| 30 | |
| 31 | #define to_clk_divider(_hw) container_of(_hw, struct clk_divider, hw) |
| 32 | |
James Hogan | 1a3cd18 | 2013-01-15 10:28:05 +0000 | [diff] [blame] | 33 | #define div_mask(d) ((1 << ((d)->width)) - 1) |
Rajendra Nayak | 6d9252b | 2012-05-17 15:52:13 +0530 | [diff] [blame] | 34 | |
Rajendra Nayak | 357c3f0 | 2012-06-29 19:06:32 +0530 | [diff] [blame] | 35 | static unsigned int _get_table_maxdiv(const struct clk_div_table *table) |
| 36 | { |
| 37 | unsigned int maxdiv = 0; |
| 38 | const struct clk_div_table *clkt; |
| 39 | |
| 40 | for (clkt = table; clkt->div; clkt++) |
| 41 | if (clkt->div > maxdiv) |
| 42 | maxdiv = clkt->div; |
| 43 | return maxdiv; |
| 44 | } |
| 45 | |
Maxime COQUELIN | 774b514 | 2014-01-29 17:24:07 +0100 | [diff] [blame] | 46 | static unsigned int _get_table_mindiv(const struct clk_div_table *table) |
| 47 | { |
| 48 | unsigned int mindiv = UINT_MAX; |
| 49 | const struct clk_div_table *clkt; |
| 50 | |
| 51 | for (clkt = table; clkt->div; clkt++) |
| 52 | if (clkt->div < mindiv) |
| 53 | mindiv = clkt->div; |
| 54 | return mindiv; |
| 55 | } |
| 56 | |
Rajendra Nayak | 6d9252b | 2012-05-17 15:52:13 +0530 | [diff] [blame] | 57 | static unsigned int _get_maxdiv(struct clk_divider *divider) |
| 58 | { |
| 59 | if (divider->flags & CLK_DIVIDER_ONE_BASED) |
| 60 | return div_mask(divider); |
| 61 | if (divider->flags & CLK_DIVIDER_POWER_OF_TWO) |
| 62 | return 1 << div_mask(divider); |
Rajendra Nayak | 357c3f0 | 2012-06-29 19:06:32 +0530 | [diff] [blame] | 63 | if (divider->table) |
| 64 | return _get_table_maxdiv(divider->table); |
Rajendra Nayak | 6d9252b | 2012-05-17 15:52:13 +0530 | [diff] [blame] | 65 | return div_mask(divider) + 1; |
| 66 | } |
| 67 | |
Rajendra Nayak | 357c3f0 | 2012-06-29 19:06:32 +0530 | [diff] [blame] | 68 | static unsigned int _get_table_div(const struct clk_div_table *table, |
| 69 | unsigned int val) |
| 70 | { |
| 71 | const struct clk_div_table *clkt; |
| 72 | |
| 73 | for (clkt = table; clkt->div; clkt++) |
| 74 | if (clkt->val == val) |
| 75 | return clkt->div; |
| 76 | return 0; |
| 77 | } |
| 78 | |
Rajendra Nayak | 6d9252b | 2012-05-17 15:52:13 +0530 | [diff] [blame] | 79 | static unsigned int _get_div(struct clk_divider *divider, unsigned int val) |
| 80 | { |
| 81 | if (divider->flags & CLK_DIVIDER_ONE_BASED) |
| 82 | return val; |
| 83 | if (divider->flags & CLK_DIVIDER_POWER_OF_TWO) |
| 84 | return 1 << val; |
Rajendra Nayak | 357c3f0 | 2012-06-29 19:06:32 +0530 | [diff] [blame] | 85 | if (divider->table) |
| 86 | return _get_table_div(divider->table, val); |
Rajendra Nayak | 6d9252b | 2012-05-17 15:52:13 +0530 | [diff] [blame] | 87 | return val + 1; |
| 88 | } |
| 89 | |
Rajendra Nayak | 357c3f0 | 2012-06-29 19:06:32 +0530 | [diff] [blame] | 90 | static unsigned int _get_table_val(const struct clk_div_table *table, |
| 91 | unsigned int div) |
| 92 | { |
| 93 | const struct clk_div_table *clkt; |
| 94 | |
| 95 | for (clkt = table; clkt->div; clkt++) |
| 96 | if (clkt->div == div) |
| 97 | return clkt->val; |
| 98 | return 0; |
| 99 | } |
| 100 | |
James Hogan | 778037e | 2013-12-16 10:41:38 +0000 | [diff] [blame] | 101 | static unsigned int _get_val(struct clk_divider *divider, unsigned int div) |
Rajendra Nayak | 6d9252b | 2012-05-17 15:52:13 +0530 | [diff] [blame] | 102 | { |
| 103 | if (divider->flags & CLK_DIVIDER_ONE_BASED) |
| 104 | return div; |
| 105 | if (divider->flags & CLK_DIVIDER_POWER_OF_TWO) |
| 106 | return __ffs(div); |
Rajendra Nayak | 357c3f0 | 2012-06-29 19:06:32 +0530 | [diff] [blame] | 107 | if (divider->table) |
| 108 | return _get_table_val(divider->table, div); |
Rajendra Nayak | 6d9252b | 2012-05-17 15:52:13 +0530 | [diff] [blame] | 109 | return div - 1; |
| 110 | } |
Mike Turquette | 9d9f78e | 2012-03-15 23:11:20 -0700 | [diff] [blame] | 111 | |
| 112 | static unsigned long clk_divider_recalc_rate(struct clk_hw *hw, |
| 113 | unsigned long parent_rate) |
| 114 | { |
| 115 | struct clk_divider *divider = to_clk_divider(hw); |
Rajendra Nayak | 6d9252b | 2012-05-17 15:52:13 +0530 | [diff] [blame] | 116 | unsigned int div, val; |
Mike Turquette | 9d9f78e | 2012-03-15 23:11:20 -0700 | [diff] [blame] | 117 | |
Gerhard Sittig | aa514ce | 2013-07-22 14:14:40 +0200 | [diff] [blame] | 118 | val = clk_readl(divider->reg) >> divider->shift; |
Rajendra Nayak | 6d9252b | 2012-05-17 15:52:13 +0530 | [diff] [blame] | 119 | val &= div_mask(divider); |
Mike Turquette | 9d9f78e | 2012-03-15 23:11:20 -0700 | [diff] [blame] | 120 | |
Rajendra Nayak | 6d9252b | 2012-05-17 15:52:13 +0530 | [diff] [blame] | 121 | div = _get_div(divider, val); |
| 122 | if (!div) { |
Soren Brinkmann | 056b2053 | 2013-04-02 15:36:56 -0700 | [diff] [blame] | 123 | WARN(!(divider->flags & CLK_DIVIDER_ALLOW_ZERO), |
| 124 | "%s: Zero divisor and CLK_DIVIDER_ALLOW_ZERO not set\n", |
| 125 | __clk_get_name(hw->clk)); |
Rajendra Nayak | 6d9252b | 2012-05-17 15:52:13 +0530 | [diff] [blame] | 126 | return parent_rate; |
| 127 | } |
Mike Turquette | 9d9f78e | 2012-03-15 23:11:20 -0700 | [diff] [blame] | 128 | |
Tomi Valkeinen | b11d282 | 2014-02-13 12:03:59 +0200 | [diff] [blame] | 129 | return DIV_ROUND_UP(parent_rate, div); |
Mike Turquette | 9d9f78e | 2012-03-15 23:11:20 -0700 | [diff] [blame] | 130 | } |
Mike Turquette | 9d9f78e | 2012-03-15 23:11:20 -0700 | [diff] [blame] | 131 | |
| 132 | /* |
| 133 | * The reverse of DIV_ROUND_UP: The maximum number which |
| 134 | * divided by m is r |
| 135 | */ |
| 136 | #define MULT_ROUND_UP(r, m) ((r) * (m) + (m) - 1) |
| 137 | |
Rajendra Nayak | 357c3f0 | 2012-06-29 19:06:32 +0530 | [diff] [blame] | 138 | static bool _is_valid_table_div(const struct clk_div_table *table, |
| 139 | unsigned int div) |
| 140 | { |
| 141 | const struct clk_div_table *clkt; |
| 142 | |
| 143 | for (clkt = table; clkt->div; clkt++) |
| 144 | if (clkt->div == div) |
| 145 | return true; |
| 146 | return false; |
| 147 | } |
| 148 | |
| 149 | static bool _is_valid_div(struct clk_divider *divider, unsigned int div) |
| 150 | { |
| 151 | if (divider->flags & CLK_DIVIDER_POWER_OF_TWO) |
James Hogan | 1a3cd18 | 2013-01-15 10:28:05 +0000 | [diff] [blame] | 152 | return is_power_of_2(div); |
Rajendra Nayak | 357c3f0 | 2012-06-29 19:06:32 +0530 | [diff] [blame] | 153 | if (divider->table) |
| 154 | return _is_valid_table_div(divider->table, div); |
| 155 | return true; |
| 156 | } |
| 157 | |
Maxime COQUELIN | dd23c2c | 2014-01-29 17:24:06 +0100 | [diff] [blame] | 158 | static int _round_up_table(const struct clk_div_table *table, int div) |
| 159 | { |
| 160 | const struct clk_div_table *clkt; |
| 161 | int up = _get_table_maxdiv(table); |
| 162 | |
| 163 | for (clkt = table; clkt->div; clkt++) { |
| 164 | if (clkt->div == div) |
| 165 | return clkt->div; |
| 166 | else if (clkt->div < div) |
| 167 | continue; |
| 168 | |
| 169 | if ((clkt->div - div) < (up - div)) |
| 170 | up = clkt->div; |
| 171 | } |
| 172 | |
| 173 | return up; |
| 174 | } |
| 175 | |
Maxime COQUELIN | 774b514 | 2014-01-29 17:24:07 +0100 | [diff] [blame] | 176 | static int _round_down_table(const struct clk_div_table *table, int div) |
| 177 | { |
| 178 | const struct clk_div_table *clkt; |
| 179 | int down = _get_table_mindiv(table); |
| 180 | |
| 181 | for (clkt = table; clkt->div; clkt++) { |
| 182 | if (clkt->div == div) |
| 183 | return clkt->div; |
| 184 | else if (clkt->div > div) |
| 185 | continue; |
| 186 | |
| 187 | if ((div - clkt->div) < (div - down)) |
| 188 | down = clkt->div; |
| 189 | } |
| 190 | |
| 191 | return down; |
| 192 | } |
| 193 | |
Maxime COQUELIN | dd23c2c | 2014-01-29 17:24:06 +0100 | [diff] [blame] | 194 | static int _div_round_up(struct clk_divider *divider, |
| 195 | unsigned long parent_rate, unsigned long rate) |
| 196 | { |
| 197 | int div = DIV_ROUND_UP(parent_rate, rate); |
| 198 | |
| 199 | if (divider->flags & CLK_DIVIDER_POWER_OF_TWO) |
| 200 | div = __roundup_pow_of_two(div); |
| 201 | if (divider->table) |
| 202 | div = _round_up_table(divider->table, div); |
| 203 | |
| 204 | return div; |
| 205 | } |
| 206 | |
Maxime COQUELIN | 774b514 | 2014-01-29 17:24:07 +0100 | [diff] [blame] | 207 | static int _div_round_closest(struct clk_divider *divider, |
| 208 | unsigned long parent_rate, unsigned long rate) |
| 209 | { |
| 210 | int up, down, div; |
| 211 | |
| 212 | up = down = div = DIV_ROUND_CLOSEST(parent_rate, rate); |
| 213 | |
| 214 | if (divider->flags & CLK_DIVIDER_POWER_OF_TWO) { |
| 215 | up = __roundup_pow_of_two(div); |
| 216 | down = __rounddown_pow_of_two(div); |
| 217 | } else if (divider->table) { |
| 218 | up = _round_up_table(divider->table, div); |
| 219 | down = _round_down_table(divider->table, div); |
| 220 | } |
| 221 | |
| 222 | return (up - div) <= (div - down) ? up : down; |
| 223 | } |
| 224 | |
| 225 | static int _div_round(struct clk_divider *divider, unsigned long parent_rate, |
| 226 | unsigned long rate) |
| 227 | { |
| 228 | if (divider->flags & CLK_DIVIDER_ROUND_CLOSEST) |
| 229 | return _div_round_closest(divider, parent_rate, rate); |
| 230 | |
| 231 | return _div_round_up(divider, parent_rate, rate); |
| 232 | } |
| 233 | |
| 234 | static bool _is_best_div(struct clk_divider *divider, |
| 235 | int rate, int now, int best) |
| 236 | { |
| 237 | if (divider->flags & CLK_DIVIDER_ROUND_CLOSEST) |
| 238 | return abs(rate - now) < abs(rate - best); |
| 239 | |
| 240 | return now <= rate && now > best; |
| 241 | } |
| 242 | |
Maxime COQUELIN | 0e2de78 | 2014-01-29 17:24:08 +0100 | [diff] [blame] | 243 | static int _next_div(struct clk_divider *divider, int div) |
| 244 | { |
| 245 | div++; |
| 246 | |
| 247 | if (divider->flags & CLK_DIVIDER_POWER_OF_TWO) |
| 248 | return __roundup_pow_of_two(div); |
| 249 | if (divider->table) |
| 250 | return _round_up_table(divider->table, div); |
| 251 | |
| 252 | return div; |
| 253 | } |
| 254 | |
Mike Turquette | 9d9f78e | 2012-03-15 23:11:20 -0700 | [diff] [blame] | 255 | static int clk_divider_bestdiv(struct clk_hw *hw, unsigned long rate, |
| 256 | unsigned long *best_parent_rate) |
| 257 | { |
| 258 | struct clk_divider *divider = to_clk_divider(hw); |
| 259 | int i, bestdiv = 0; |
| 260 | unsigned long parent_rate, best = 0, now, maxdiv; |
Shawn Guo | 081c902 | 2013-06-02 22:20:55 +0800 | [diff] [blame] | 261 | unsigned long parent_rate_saved = *best_parent_rate; |
Mike Turquette | 9d9f78e | 2012-03-15 23:11:20 -0700 | [diff] [blame] | 262 | |
| 263 | if (!rate) |
| 264 | rate = 1; |
| 265 | |
Rajendra Nayak | 6d9252b | 2012-05-17 15:52:13 +0530 | [diff] [blame] | 266 | maxdiv = _get_maxdiv(divider); |
Mike Turquette | 9d9f78e | 2012-03-15 23:11:20 -0700 | [diff] [blame] | 267 | |
Shawn Guo | 81536e0 | 2012-04-12 20:50:17 +0800 | [diff] [blame] | 268 | if (!(__clk_get_flags(hw->clk) & CLK_SET_RATE_PARENT)) { |
| 269 | parent_rate = *best_parent_rate; |
Maxime COQUELIN | 774b514 | 2014-01-29 17:24:07 +0100 | [diff] [blame] | 270 | bestdiv = _div_round(divider, parent_rate, rate); |
Mike Turquette | 9d9f78e | 2012-03-15 23:11:20 -0700 | [diff] [blame] | 271 | bestdiv = bestdiv == 0 ? 1 : bestdiv; |
| 272 | bestdiv = bestdiv > maxdiv ? maxdiv : bestdiv; |
| 273 | return bestdiv; |
| 274 | } |
| 275 | |
| 276 | /* |
| 277 | * The maximum divider we can use without overflowing |
| 278 | * unsigned long in rate * i below |
| 279 | */ |
| 280 | maxdiv = min(ULONG_MAX / rate, maxdiv); |
| 281 | |
Maxime COQUELIN | 0e2de78 | 2014-01-29 17:24:08 +0100 | [diff] [blame] | 282 | for (i = 1; i <= maxdiv; i = _next_div(divider, i)) { |
Rajendra Nayak | 357c3f0 | 2012-06-29 19:06:32 +0530 | [diff] [blame] | 283 | if (!_is_valid_div(divider, i)) |
Rajendra Nayak | 6d9252b | 2012-05-17 15:52:13 +0530 | [diff] [blame] | 284 | continue; |
Shawn Guo | 081c902 | 2013-06-02 22:20:55 +0800 | [diff] [blame] | 285 | if (rate * i == parent_rate_saved) { |
| 286 | /* |
| 287 | * It's the most ideal case if the requested rate can be |
| 288 | * divided from parent clock without needing to change |
| 289 | * parent rate, so return the divider immediately. |
| 290 | */ |
| 291 | *best_parent_rate = parent_rate_saved; |
| 292 | return i; |
| 293 | } |
Mike Turquette | 9d9f78e | 2012-03-15 23:11:20 -0700 | [diff] [blame] | 294 | parent_rate = __clk_round_rate(__clk_get_parent(hw->clk), |
| 295 | MULT_ROUND_UP(rate, i)); |
Tomi Valkeinen | b11d282 | 2014-02-13 12:03:59 +0200 | [diff] [blame] | 296 | now = DIV_ROUND_UP(parent_rate, i); |
Maxime COQUELIN | 774b514 | 2014-01-29 17:24:07 +0100 | [diff] [blame] | 297 | if (_is_best_div(divider, rate, now, best)) { |
Mike Turquette | 9d9f78e | 2012-03-15 23:11:20 -0700 | [diff] [blame] | 298 | bestdiv = i; |
| 299 | best = now; |
| 300 | *best_parent_rate = parent_rate; |
| 301 | } |
| 302 | } |
| 303 | |
| 304 | if (!bestdiv) { |
Rajendra Nayak | 6d9252b | 2012-05-17 15:52:13 +0530 | [diff] [blame] | 305 | bestdiv = _get_maxdiv(divider); |
Mike Turquette | 9d9f78e | 2012-03-15 23:11:20 -0700 | [diff] [blame] | 306 | *best_parent_rate = __clk_round_rate(__clk_get_parent(hw->clk), 1); |
| 307 | } |
| 308 | |
| 309 | return bestdiv; |
| 310 | } |
| 311 | |
| 312 | static long clk_divider_round_rate(struct clk_hw *hw, unsigned long rate, |
| 313 | unsigned long *prate) |
| 314 | { |
| 315 | int div; |
| 316 | div = clk_divider_bestdiv(hw, rate, prate); |
| 317 | |
Tomi Valkeinen | b11d282 | 2014-02-13 12:03:59 +0200 | [diff] [blame] | 318 | return DIV_ROUND_UP(*prate, div); |
Mike Turquette | 9d9f78e | 2012-03-15 23:11:20 -0700 | [diff] [blame] | 319 | } |
Mike Turquette | 9d9f78e | 2012-03-15 23:11:20 -0700 | [diff] [blame] | 320 | |
Shawn Guo | 1c0035d | 2012-04-12 20:50:18 +0800 | [diff] [blame] | 321 | static int clk_divider_set_rate(struct clk_hw *hw, unsigned long rate, |
| 322 | unsigned long parent_rate) |
Mike Turquette | 9d9f78e | 2012-03-15 23:11:20 -0700 | [diff] [blame] | 323 | { |
| 324 | struct clk_divider *divider = to_clk_divider(hw); |
Rajendra Nayak | 6d9252b | 2012-05-17 15:52:13 +0530 | [diff] [blame] | 325 | unsigned int div, value; |
Mike Turquette | 9d9f78e | 2012-03-15 23:11:20 -0700 | [diff] [blame] | 326 | unsigned long flags = 0; |
| 327 | u32 val; |
| 328 | |
Tomi Valkeinen | b11d282 | 2014-02-13 12:03:59 +0200 | [diff] [blame] | 329 | div = DIV_ROUND_UP(parent_rate, rate); |
Maxime COQUELIN | dd23c2c | 2014-01-29 17:24:06 +0100 | [diff] [blame] | 330 | |
| 331 | if (!_is_valid_div(divider, div)) |
| 332 | return -EINVAL; |
| 333 | |
Rajendra Nayak | 6d9252b | 2012-05-17 15:52:13 +0530 | [diff] [blame] | 334 | value = _get_val(divider, div); |
Mike Turquette | 9d9f78e | 2012-03-15 23:11:20 -0700 | [diff] [blame] | 335 | |
Rajendra Nayak | 6d9252b | 2012-05-17 15:52:13 +0530 | [diff] [blame] | 336 | if (value > div_mask(divider)) |
| 337 | value = div_mask(divider); |
Mike Turquette | 9d9f78e | 2012-03-15 23:11:20 -0700 | [diff] [blame] | 338 | |
| 339 | if (divider->lock) |
| 340 | spin_lock_irqsave(divider->lock, flags); |
| 341 | |
Haojian Zhuang | d57dfe7 | 2013-06-08 22:47:18 +0800 | [diff] [blame] | 342 | if (divider->flags & CLK_DIVIDER_HIWORD_MASK) { |
| 343 | val = div_mask(divider) << (divider->shift + 16); |
| 344 | } else { |
Gerhard Sittig | aa514ce | 2013-07-22 14:14:40 +0200 | [diff] [blame] | 345 | val = clk_readl(divider->reg); |
Haojian Zhuang | d57dfe7 | 2013-06-08 22:47:18 +0800 | [diff] [blame] | 346 | val &= ~(div_mask(divider) << divider->shift); |
| 347 | } |
Rajendra Nayak | 6d9252b | 2012-05-17 15:52:13 +0530 | [diff] [blame] | 348 | val |= value << divider->shift; |
Gerhard Sittig | aa514ce | 2013-07-22 14:14:40 +0200 | [diff] [blame] | 349 | clk_writel(val, divider->reg); |
Mike Turquette | 9d9f78e | 2012-03-15 23:11:20 -0700 | [diff] [blame] | 350 | |
| 351 | if (divider->lock) |
| 352 | spin_unlock_irqrestore(divider->lock, flags); |
| 353 | |
| 354 | return 0; |
| 355 | } |
Mike Turquette | 9d9f78e | 2012-03-15 23:11:20 -0700 | [diff] [blame] | 356 | |
Shawn Guo | 822c250 | 2012-03-27 15:23:22 +0800 | [diff] [blame] | 357 | const struct clk_ops clk_divider_ops = { |
Mike Turquette | 9d9f78e | 2012-03-15 23:11:20 -0700 | [diff] [blame] | 358 | .recalc_rate = clk_divider_recalc_rate, |
| 359 | .round_rate = clk_divider_round_rate, |
| 360 | .set_rate = clk_divider_set_rate, |
| 361 | }; |
| 362 | EXPORT_SYMBOL_GPL(clk_divider_ops); |
| 363 | |
Heiko Stuebner | 79c6ab5 | 2014-05-23 18:32:15 +0530 | [diff] [blame^] | 364 | const struct clk_ops clk_divider_ro_ops = { |
| 365 | .recalc_rate = clk_divider_recalc_rate, |
| 366 | }; |
| 367 | EXPORT_SYMBOL_GPL(clk_divider_ro_ops); |
| 368 | |
Rajendra Nayak | 357c3f0 | 2012-06-29 19:06:32 +0530 | [diff] [blame] | 369 | static struct clk *_register_divider(struct device *dev, const char *name, |
Mike Turquette | 9d9f78e | 2012-03-15 23:11:20 -0700 | [diff] [blame] | 370 | const char *parent_name, unsigned long flags, |
| 371 | void __iomem *reg, u8 shift, u8 width, |
Rajendra Nayak | 357c3f0 | 2012-06-29 19:06:32 +0530 | [diff] [blame] | 372 | u8 clk_divider_flags, const struct clk_div_table *table, |
| 373 | spinlock_t *lock) |
Mike Turquette | 9d9f78e | 2012-03-15 23:11:20 -0700 | [diff] [blame] | 374 | { |
| 375 | struct clk_divider *div; |
| 376 | struct clk *clk; |
Saravana Kannan | 0197b3e | 2012-04-25 22:58:56 -0700 | [diff] [blame] | 377 | struct clk_init_data init; |
Mike Turquette | 9d9f78e | 2012-03-15 23:11:20 -0700 | [diff] [blame] | 378 | |
Haojian Zhuang | d57dfe7 | 2013-06-08 22:47:18 +0800 | [diff] [blame] | 379 | if (clk_divider_flags & CLK_DIVIDER_HIWORD_MASK) { |
| 380 | if (width + shift > 16) { |
| 381 | pr_warn("divider value exceeds LOWORD field\n"); |
| 382 | return ERR_PTR(-EINVAL); |
| 383 | } |
| 384 | } |
| 385 | |
Mike Turquette | 27d5459 | 2012-03-26 17:51:03 -0700 | [diff] [blame] | 386 | /* allocate the divider */ |
Mike Turquette | 9d9f78e | 2012-03-15 23:11:20 -0700 | [diff] [blame] | 387 | div = kzalloc(sizeof(struct clk_divider), GFP_KERNEL); |
Mike Turquette | 9d9f78e | 2012-03-15 23:11:20 -0700 | [diff] [blame] | 388 | if (!div) { |
| 389 | pr_err("%s: could not allocate divider clk\n", __func__); |
Mike Turquette | 27d5459 | 2012-03-26 17:51:03 -0700 | [diff] [blame] | 390 | return ERR_PTR(-ENOMEM); |
Mike Turquette | 9d9f78e | 2012-03-15 23:11:20 -0700 | [diff] [blame] | 391 | } |
| 392 | |
Saravana Kannan | 0197b3e | 2012-04-25 22:58:56 -0700 | [diff] [blame] | 393 | init.name = name; |
Heiko Stuebner | 79c6ab5 | 2014-05-23 18:32:15 +0530 | [diff] [blame^] | 394 | if (clk_divider_flags & CLK_DIVIDER_READ_ONLY) |
| 395 | init.ops = &clk_divider_ro_ops; |
| 396 | else |
| 397 | init.ops = &clk_divider_ops; |
Rajendra Nayak | f7d8caa | 2012-06-01 14:02:47 +0530 | [diff] [blame] | 398 | init.flags = flags | CLK_IS_BASIC; |
Saravana Kannan | 0197b3e | 2012-04-25 22:58:56 -0700 | [diff] [blame] | 399 | init.parent_names = (parent_name ? &parent_name: NULL); |
| 400 | init.num_parents = (parent_name ? 1 : 0); |
| 401 | |
Mike Turquette | 9d9f78e | 2012-03-15 23:11:20 -0700 | [diff] [blame] | 402 | /* struct clk_divider assignments */ |
| 403 | div->reg = reg; |
| 404 | div->shift = shift; |
| 405 | div->width = width; |
| 406 | div->flags = clk_divider_flags; |
| 407 | div->lock = lock; |
Saravana Kannan | 0197b3e | 2012-04-25 22:58:56 -0700 | [diff] [blame] | 408 | div->hw.init = &init; |
Rajendra Nayak | 357c3f0 | 2012-06-29 19:06:32 +0530 | [diff] [blame] | 409 | div->table = table; |
Mike Turquette | 9d9f78e | 2012-03-15 23:11:20 -0700 | [diff] [blame] | 410 | |
Mike Turquette | 27d5459 | 2012-03-26 17:51:03 -0700 | [diff] [blame] | 411 | /* register the clock */ |
Saravana Kannan | 0197b3e | 2012-04-25 22:58:56 -0700 | [diff] [blame] | 412 | clk = clk_register(dev, &div->hw); |
Mike Turquette | 9d9f78e | 2012-03-15 23:11:20 -0700 | [diff] [blame] | 413 | |
Mike Turquette | 27d5459 | 2012-03-26 17:51:03 -0700 | [diff] [blame] | 414 | if (IS_ERR(clk)) |
| 415 | kfree(div); |
Mike Turquette | 9d9f78e | 2012-03-15 23:11:20 -0700 | [diff] [blame] | 416 | |
Mike Turquette | 27d5459 | 2012-03-26 17:51:03 -0700 | [diff] [blame] | 417 | return clk; |
Mike Turquette | 9d9f78e | 2012-03-15 23:11:20 -0700 | [diff] [blame] | 418 | } |
Rajendra Nayak | 357c3f0 | 2012-06-29 19:06:32 +0530 | [diff] [blame] | 419 | |
| 420 | /** |
| 421 | * clk_register_divider - register a divider clock with the clock framework |
| 422 | * @dev: device registering this clock |
| 423 | * @name: name of this clock |
| 424 | * @parent_name: name of clock's parent |
| 425 | * @flags: framework-specific flags |
| 426 | * @reg: register address to adjust divider |
| 427 | * @shift: number of bits to shift the bitfield |
| 428 | * @width: width of the bitfield |
| 429 | * @clk_divider_flags: divider-specific flags for this clock |
| 430 | * @lock: shared register lock for this clock |
| 431 | */ |
| 432 | struct clk *clk_register_divider(struct device *dev, const char *name, |
| 433 | const char *parent_name, unsigned long flags, |
| 434 | void __iomem *reg, u8 shift, u8 width, |
| 435 | u8 clk_divider_flags, spinlock_t *lock) |
| 436 | { |
| 437 | return _register_divider(dev, name, parent_name, flags, reg, shift, |
| 438 | width, clk_divider_flags, NULL, lock); |
| 439 | } |
Fabio Estevam | 4c5eeea | 2013-08-02 13:14:07 -0300 | [diff] [blame] | 440 | EXPORT_SYMBOL_GPL(clk_register_divider); |
Rajendra Nayak | 357c3f0 | 2012-06-29 19:06:32 +0530 | [diff] [blame] | 441 | |
| 442 | /** |
| 443 | * clk_register_divider_table - register a table based divider clock with |
| 444 | * the clock framework |
| 445 | * @dev: device registering this clock |
| 446 | * @name: name of this clock |
| 447 | * @parent_name: name of clock's parent |
| 448 | * @flags: framework-specific flags |
| 449 | * @reg: register address to adjust divider |
| 450 | * @shift: number of bits to shift the bitfield |
| 451 | * @width: width of the bitfield |
| 452 | * @clk_divider_flags: divider-specific flags for this clock |
| 453 | * @table: array of divider/value pairs ending with a div set to 0 |
| 454 | * @lock: shared register lock for this clock |
| 455 | */ |
| 456 | struct clk *clk_register_divider_table(struct device *dev, const char *name, |
| 457 | const char *parent_name, unsigned long flags, |
| 458 | void __iomem *reg, u8 shift, u8 width, |
| 459 | u8 clk_divider_flags, const struct clk_div_table *table, |
| 460 | spinlock_t *lock) |
| 461 | { |
| 462 | return _register_divider(dev, name, parent_name, flags, reg, shift, |
| 463 | width, clk_divider_flags, table, lock); |
| 464 | } |
Fabio Estevam | 4c5eeea | 2013-08-02 13:14:07 -0300 | [diff] [blame] | 465 | EXPORT_SYMBOL_GPL(clk_register_divider_table); |