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v3.5.6
 
  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>
 
 19
 20/*
 21 * DOC: basic adjustable divider clock that cannot gate
 22 *
 23 * Traits of this clock:
 24 * prepare - clk_prepare only ensures that parents are prepared
 25 * enable - clk_enable only ensures that parents are enabled
 26 * rate - rate is adjustable.  clk->rate = parent->rate / divisor
 27 * parent - fixed parent.  No clk_set_parent support
 28 */
 29
 30#define to_clk_divider(_hw) container_of(_hw, struct clk_divider, hw)
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 31
 32#define div_mask(d)	((1 << (d->width)) - 1)
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 33
 34static unsigned long clk_divider_recalc_rate(struct clk_hw *hw,
 35		unsigned long parent_rate)
 36{
 37	struct clk_divider *divider = to_clk_divider(hw);
 38	unsigned int div;
 39
 40	div = readl(divider->reg) >> divider->shift;
 41	div &= div_mask(divider);
 42
 43	if (!(divider->flags & CLK_DIVIDER_ONE_BASED))
 44		div++;
 
 
 
 
 
 
 45
 46	return parent_rate / div;
 
 
 
 47}
 48
 49/*
 50 * The reverse of DIV_ROUND_UP: The maximum number which
 51 * divided by m is r
 52 */
 53#define MULT_ROUND_UP(r, m) ((r) * (m) + (m) - 1)
 
 
 
 
 54
 55static int clk_divider_bestdiv(struct clk_hw *hw, unsigned long rate,
 56		unsigned long *best_parent_rate)
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 57{
 58	struct clk_divider *divider = to_clk_divider(hw);
 59	int i, bestdiv = 0;
 60	unsigned long parent_rate, best = 0, now, maxdiv;
 
 61
 62	if (!rate)
 63		rate = 1;
 64
 65	maxdiv = (1 << divider->width);
 66
 67	if (divider->flags & CLK_DIVIDER_ONE_BASED)
 68		maxdiv--;
 69
 70	if (!(__clk_get_flags(hw->clk) & CLK_SET_RATE_PARENT)) {
 71		parent_rate = *best_parent_rate;
 72		bestdiv = DIV_ROUND_UP(parent_rate, rate);
 73		bestdiv = bestdiv == 0 ? 1 : bestdiv;
 74		bestdiv = bestdiv > maxdiv ? maxdiv : bestdiv;
 75		return bestdiv;
 76	}
 77
 78	/*
 79	 * The maximum divider we can use without overflowing
 80	 * unsigned long in rate * i below
 81	 */
 82	maxdiv = min(ULONG_MAX / rate, maxdiv);
 83
 84	for (i = 1; i <= maxdiv; i++) {
 85		parent_rate = __clk_round_rate(__clk_get_parent(hw->clk),
 86				MULT_ROUND_UP(rate, i));
 87		now = parent_rate / i;
 88		if (now <= rate && now > best) {
 
 
 
 
 
 
 
 
 
 89			bestdiv = i;
 90			best = now;
 91			*best_parent_rate = parent_rate;
 92		}
 93	}
 94
 95	if (!bestdiv) {
 96		bestdiv = (1 << divider->width);
 97		if (divider->flags & CLK_DIVIDER_ONE_BASED)
 98			bestdiv--;
 99		*best_parent_rate = __clk_round_rate(__clk_get_parent(hw->clk), 1);
100	}
101
102	return bestdiv;
103}
104
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
105static long clk_divider_round_rate(struct clk_hw *hw, unsigned long rate,
106				unsigned long *prate)
107{
108	int div;
109	div = clk_divider_bestdiv(hw, rate, prate);
 
 
 
 
 
 
 
 
 
 
 
110
111	return *prate / div;
 
112}
113
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
114static int clk_divider_set_rate(struct clk_hw *hw, unsigned long rate,
115				unsigned long parent_rate)
116{
117	struct clk_divider *divider = to_clk_divider(hw);
118	unsigned int div;
119	unsigned long flags = 0;
120	u32 val;
121
122	div = parent_rate / rate;
123
124	if (!(divider->flags & CLK_DIVIDER_ONE_BASED))
125		div--;
126
127	if (div > div_mask(divider))
128		div = div_mask(divider);
129
130	if (divider->lock)
131		spin_lock_irqsave(divider->lock, flags);
 
 
132
133	val = readl(divider->reg);
134	val &= ~(div_mask(divider) << divider->shift);
135	val |= div << divider->shift;
136	writel(val, divider->reg);
 
 
 
 
137
138	if (divider->lock)
139		spin_unlock_irqrestore(divider->lock, flags);
 
 
140
141	return 0;
142}
143
144const struct clk_ops clk_divider_ops = {
145	.recalc_rate = clk_divider_recalc_rate,
146	.round_rate = clk_divider_round_rate,
147	.set_rate = clk_divider_set_rate,
148};
149EXPORT_SYMBOL_GPL(clk_divider_ops);
150
151/**
152 * clk_register_divider - register a divider clock with the clock framework
153 * @dev: device registering this clock
154 * @name: name of this clock
155 * @parent_name: name of clock's parent
156 * @flags: framework-specific flags
157 * @reg: register address to adjust divider
158 * @shift: number of bits to shift the bitfield
159 * @width: width of the bitfield
160 * @clk_divider_flags: divider-specific flags for this clock
161 * @lock: shared register lock for this clock
162 */
163struct clk *clk_register_divider(struct device *dev, const char *name,
164		const char *parent_name, unsigned long flags,
165		void __iomem *reg, u8 shift, u8 width,
166		u8 clk_divider_flags, spinlock_t *lock)
167{
168	struct clk_divider *div;
169	struct clk *clk;
170	struct clk_init_data init;
 
 
 
 
 
 
 
 
171
172	/* allocate the divider */
173	div = kzalloc(sizeof(struct clk_divider), GFP_KERNEL);
174	if (!div) {
175		pr_err("%s: could not allocate divider clk\n", __func__);
176		return ERR_PTR(-ENOMEM);
177	}
178
179	init.name = name;
180	init.ops = &clk_divider_ops;
 
 
 
181	init.flags = flags;
182	init.parent_names = (parent_name ? &parent_name: NULL);
183	init.num_parents = (parent_name ? 1 : 0);
184
185	/* struct clk_divider assignments */
186	div->reg = reg;
187	div->shift = shift;
188	div->width = width;
189	div->flags = clk_divider_flags;
190	div->lock = lock;
191	div->hw.init = &init;
 
192
193	/* register the clock */
194	clk = clk_register(dev, &div->hw);
195
196	if (IS_ERR(clk))
197		kfree(div);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
198
199	return clk;
 
200}
v5.9
  1// SPDX-License-Identifier: GPL-2.0
  2/*
  3 * Copyright (C) 2011 Sascha Hauer, Pengutronix <s.hauer@pengutronix.de>
  4 * Copyright (C) 2011 Richard Zhao, Linaro <richard.zhao@linaro.org>
  5 * Copyright (C) 2011-2012 Mike Turquette, Linaro Ltd <mturquette@linaro.org>
  6 *
 
 
 
 
  7 * Adjustable divider clock implementation
  8 */
  9
 10#include <linux/clk-provider.h>
 11#include <linux/module.h>
 12#include <linux/slab.h>
 13#include <linux/io.h>
 14#include <linux/err.h>
 15#include <linux/string.h>
 16#include <linux/log2.h>
 17
 18/*
 19 * DOC: basic adjustable divider clock that cannot gate
 20 *
 21 * Traits of this clock:
 22 * prepare - clk_prepare only ensures that parents are prepared
 23 * enable - clk_enable only ensures that parents are enabled
 24 * rate - rate is adjustable.  clk->rate = ceiling(parent->rate / divisor)
 25 * parent - fixed parent.  No clk_set_parent support
 26 */
 27
 28static inline u32 clk_div_readl(struct clk_divider *divider)
 29{
 30	if (divider->flags & CLK_DIVIDER_BIG_ENDIAN)
 31		return ioread32be(divider->reg);
 32
 33	return readl(divider->reg);
 34}
 35
 36static inline void clk_div_writel(struct clk_divider *divider, u32 val)
 37{
 38	if (divider->flags & CLK_DIVIDER_BIG_ENDIAN)
 39		iowrite32be(val, divider->reg);
 40	else
 41		writel(val, divider->reg);
 42}
 43
 44static unsigned int _get_table_maxdiv(const struct clk_div_table *table,
 45				      u8 width)
 46{
 47	unsigned int maxdiv = 0, mask = clk_div_mask(width);
 48	const struct clk_div_table *clkt;
 49
 50	for (clkt = table; clkt->div; clkt++)
 51		if (clkt->div > maxdiv && clkt->val <= mask)
 52			maxdiv = clkt->div;
 53	return maxdiv;
 54}
 55
 56static unsigned int _get_table_mindiv(const struct clk_div_table *table)
 57{
 58	unsigned int mindiv = UINT_MAX;
 59	const struct clk_div_table *clkt;
 60
 61	for (clkt = table; clkt->div; clkt++)
 62		if (clkt->div < mindiv)
 63			mindiv = clkt->div;
 64	return mindiv;
 65}
 66
 67static unsigned int _get_maxdiv(const struct clk_div_table *table, u8 width,
 68				unsigned long flags)
 69{
 70	if (flags & CLK_DIVIDER_ONE_BASED)
 71		return clk_div_mask(width);
 72	if (flags & CLK_DIVIDER_POWER_OF_TWO)
 73		return 1 << clk_div_mask(width);
 74	if (table)
 75		return _get_table_maxdiv(table, width);
 76	return clk_div_mask(width) + 1;
 77}
 78
 79static unsigned int _get_table_div(const struct clk_div_table *table,
 80							unsigned int val)
 81{
 82	const struct clk_div_table *clkt;
 83
 84	for (clkt = table; clkt->div; clkt++)
 85		if (clkt->val == val)
 86			return clkt->div;
 87	return 0;
 88}
 89
 90static unsigned int _get_div(const struct clk_div_table *table,
 91			     unsigned int val, unsigned long flags, u8 width)
 92{
 93	if (flags & CLK_DIVIDER_ONE_BASED)
 94		return val;
 95	if (flags & CLK_DIVIDER_POWER_OF_TWO)
 96		return 1 << val;
 97	if (flags & CLK_DIVIDER_MAX_AT_ZERO)
 98		return val ? val : clk_div_mask(width) + 1;
 99	if (table)
100		return _get_table_div(table, val);
101	return val + 1;
102}
103
104static unsigned int _get_table_val(const struct clk_div_table *table,
105							unsigned int div)
106{
107	const struct clk_div_table *clkt;
108
109	for (clkt = table; clkt->div; clkt++)
110		if (clkt->div == div)
111			return clkt->val;
112	return 0;
113}
114
115static unsigned int _get_val(const struct clk_div_table *table,
116			     unsigned int div, unsigned long flags, u8 width)
117{
118	if (flags & CLK_DIVIDER_ONE_BASED)
119		return div;
120	if (flags & CLK_DIVIDER_POWER_OF_TWO)
121		return __ffs(div);
122	if (flags & CLK_DIVIDER_MAX_AT_ZERO)
123		return (div == clk_div_mask(width) + 1) ? 0 : div;
124	if (table)
125		return  _get_table_val(table, div);
126	return div - 1;
127}
128
129unsigned long divider_recalc_rate(struct clk_hw *hw, unsigned long parent_rate,
130				  unsigned int val,
131				  const struct clk_div_table *table,
132				  unsigned long flags, unsigned long width)
133{
134	unsigned int div;
135
136	div = _get_div(table, val, flags, width);
137	if (!div) {
138		WARN(!(flags & CLK_DIVIDER_ALLOW_ZERO),
139			"%s: Zero divisor and CLK_DIVIDER_ALLOW_ZERO not set\n",
140			clk_hw_get_name(hw));
141		return parent_rate;
142	}
143
144	return DIV_ROUND_UP_ULL((u64)parent_rate, div);
145}
146EXPORT_SYMBOL_GPL(divider_recalc_rate);
147
148static unsigned long clk_divider_recalc_rate(struct clk_hw *hw,
149		unsigned long parent_rate)
150{
151	struct clk_divider *divider = to_clk_divider(hw);
152	unsigned int val;
153
154	val = clk_div_readl(divider) >> divider->shift;
155	val &= clk_div_mask(divider->width);
156
157	return divider_recalc_rate(hw, parent_rate, val, divider->table,
158				   divider->flags, divider->width);
159}
160
161static bool _is_valid_table_div(const struct clk_div_table *table,
162							 unsigned int div)
163{
164	const struct clk_div_table *clkt;
165
166	for (clkt = table; clkt->div; clkt++)
167		if (clkt->div == div)
168			return true;
169	return false;
170}
171
172static bool _is_valid_div(const struct clk_div_table *table, unsigned int div,
173			  unsigned long flags)
174{
175	if (flags & CLK_DIVIDER_POWER_OF_TWO)
176		return is_power_of_2(div);
177	if (table)
178		return _is_valid_table_div(table, div);
179	return true;
180}
181
182static int _round_up_table(const struct clk_div_table *table, int div)
183{
184	const struct clk_div_table *clkt;
185	int up = INT_MAX;
186
187	for (clkt = table; clkt->div; clkt++) {
188		if (clkt->div == div)
189			return clkt->div;
190		else if (clkt->div < div)
191			continue;
192
193		if ((clkt->div - div) < (up - div))
194			up = clkt->div;
195	}
196
197	return up;
198}
199
200static int _round_down_table(const struct clk_div_table *table, int div)
201{
202	const struct clk_div_table *clkt;
203	int down = _get_table_mindiv(table);
204
205	for (clkt = table; clkt->div; clkt++) {
206		if (clkt->div == div)
207			return clkt->div;
208		else if (clkt->div > div)
209			continue;
210
211		if ((div - clkt->div) < (div - down))
212			down = clkt->div;
213	}
214
215	return down;
216}
217
218static int _div_round_up(const struct clk_div_table *table,
219			 unsigned long parent_rate, unsigned long rate,
220			 unsigned long flags)
221{
222	int div = DIV_ROUND_UP_ULL((u64)parent_rate, rate);
223
224	if (flags & CLK_DIVIDER_POWER_OF_TWO)
225		div = __roundup_pow_of_two(div);
226	if (table)
227		div = _round_up_table(table, div);
228
229	return div;
230}
231
232static int _div_round_closest(const struct clk_div_table *table,
233			      unsigned long parent_rate, unsigned long rate,
234			      unsigned long flags)
235{
236	int up, down;
237	unsigned long up_rate, down_rate;
238
239	up = DIV_ROUND_UP_ULL((u64)parent_rate, rate);
240	down = parent_rate / rate;
241
242	if (flags & CLK_DIVIDER_POWER_OF_TWO) {
243		up = __roundup_pow_of_two(up);
244		down = __rounddown_pow_of_two(down);
245	} else if (table) {
246		up = _round_up_table(table, up);
247		down = _round_down_table(table, down);
248	}
249
250	up_rate = DIV_ROUND_UP_ULL((u64)parent_rate, up);
251	down_rate = DIV_ROUND_UP_ULL((u64)parent_rate, down);
252
253	return (rate - up_rate) <= (down_rate - rate) ? up : down;
254}
255
256static int _div_round(const struct clk_div_table *table,
257		      unsigned long parent_rate, unsigned long rate,
258		      unsigned long flags)
259{
260	if (flags & CLK_DIVIDER_ROUND_CLOSEST)
261		return _div_round_closest(table, parent_rate, rate, flags);
262
263	return _div_round_up(table, parent_rate, rate, flags);
264}
265
266static bool _is_best_div(unsigned long rate, unsigned long now,
267			 unsigned long best, unsigned long flags)
268{
269	if (flags & CLK_DIVIDER_ROUND_CLOSEST)
270		return abs(rate - now) < abs(rate - best);
271
272	return now <= rate && now > best;
273}
274
275static int _next_div(const struct clk_div_table *table, int div,
276		     unsigned long flags)
277{
278	div++;
279
280	if (flags & CLK_DIVIDER_POWER_OF_TWO)
281		return __roundup_pow_of_two(div);
282	if (table)
283		return _round_up_table(table, div);
284
285	return div;
286}
287
288static int clk_divider_bestdiv(struct clk_hw *hw, struct clk_hw *parent,
289			       unsigned long rate,
290			       unsigned long *best_parent_rate,
291			       const struct clk_div_table *table, u8 width,
292			       unsigned long flags)
293{
 
294	int i, bestdiv = 0;
295	unsigned long parent_rate, best = 0, now, maxdiv;
296	unsigned long parent_rate_saved = *best_parent_rate;
297
298	if (!rate)
299		rate = 1;
300
301	maxdiv = _get_maxdiv(table, width, flags);
 
 
 
302
303	if (!(clk_hw_get_flags(hw) & CLK_SET_RATE_PARENT)) {
304		parent_rate = *best_parent_rate;
305		bestdiv = _div_round(table, parent_rate, rate, flags);
306		bestdiv = bestdiv == 0 ? 1 : bestdiv;
307		bestdiv = bestdiv > maxdiv ? maxdiv : bestdiv;
308		return bestdiv;
309	}
310
311	/*
312	 * The maximum divider we can use without overflowing
313	 * unsigned long in rate * i below
314	 */
315	maxdiv = min(ULONG_MAX / rate, maxdiv);
316
317	for (i = _next_div(table, 0, flags); i <= maxdiv;
318					     i = _next_div(table, i, flags)) {
319		if (rate * i == parent_rate_saved) {
320			/*
321			 * It's the most ideal case if the requested rate can be
322			 * divided from parent clock without needing to change
323			 * parent rate, so return the divider immediately.
324			 */
325			*best_parent_rate = parent_rate_saved;
326			return i;
327		}
328		parent_rate = clk_hw_round_rate(parent, rate * i);
329		now = DIV_ROUND_UP_ULL((u64)parent_rate, i);
330		if (_is_best_div(rate, now, best, flags)) {
331			bestdiv = i;
332			best = now;
333			*best_parent_rate = parent_rate;
334		}
335	}
336
337	if (!bestdiv) {
338		bestdiv = _get_maxdiv(table, width, flags);
339		*best_parent_rate = clk_hw_round_rate(parent, 1);
 
 
340	}
341
342	return bestdiv;
343}
344
345long divider_round_rate_parent(struct clk_hw *hw, struct clk_hw *parent,
346			       unsigned long rate, unsigned long *prate,
347			       const struct clk_div_table *table,
348			       u8 width, unsigned long flags)
349{
350	int div;
351
352	div = clk_divider_bestdiv(hw, parent, rate, prate, table, width, flags);
353
354	return DIV_ROUND_UP_ULL((u64)*prate, div);
355}
356EXPORT_SYMBOL_GPL(divider_round_rate_parent);
357
358long divider_ro_round_rate_parent(struct clk_hw *hw, struct clk_hw *parent,
359				  unsigned long rate, unsigned long *prate,
360				  const struct clk_div_table *table, u8 width,
361				  unsigned long flags, unsigned int val)
362{
363	int div;
364
365	div = _get_div(table, val, flags, width);
366
367	/* Even a read-only clock can propagate a rate change */
368	if (clk_hw_get_flags(hw) & CLK_SET_RATE_PARENT) {
369		if (!parent)
370			return -EINVAL;
371
372		*prate = clk_hw_round_rate(parent, rate * div);
373	}
374
375	return DIV_ROUND_UP_ULL((u64)*prate, div);
376}
377EXPORT_SYMBOL_GPL(divider_ro_round_rate_parent);
378
379
380static long clk_divider_round_rate(struct clk_hw *hw, unsigned long rate,
381				unsigned long *prate)
382{
383	struct clk_divider *divider = to_clk_divider(hw);
384
385	/* if read only, just return current value */
386	if (divider->flags & CLK_DIVIDER_READ_ONLY) {
387		u32 val;
388
389		val = clk_div_readl(divider) >> divider->shift;
390		val &= clk_div_mask(divider->width);
391
392		return divider_ro_round_rate(hw, rate, prate, divider->table,
393					     divider->width, divider->flags,
394					     val);
395	}
396
397	return divider_round_rate(hw, rate, prate, divider->table,
398				  divider->width, divider->flags);
399}
400
401int divider_get_val(unsigned long rate, unsigned long parent_rate,
402		    const struct clk_div_table *table, u8 width,
403		    unsigned long flags)
404{
405	unsigned int div, value;
406
407	div = DIV_ROUND_UP_ULL((u64)parent_rate, rate);
408
409	if (!_is_valid_div(table, div, flags))
410		return -EINVAL;
411
412	value = _get_val(table, div, flags, width);
413
414	return min_t(unsigned int, value, clk_div_mask(width));
415}
416EXPORT_SYMBOL_GPL(divider_get_val);
417
418static int clk_divider_set_rate(struct clk_hw *hw, unsigned long rate,
419				unsigned long parent_rate)
420{
421	struct clk_divider *divider = to_clk_divider(hw);
422	int value;
423	unsigned long flags = 0;
424	u32 val;
425
426	value = divider_get_val(rate, parent_rate, divider->table,
427				divider->width, divider->flags);
428	if (value < 0)
429		return value;
 
 
 
430
431	if (divider->lock)
432		spin_lock_irqsave(divider->lock, flags);
433	else
434		__acquire(divider->lock);
435
436	if (divider->flags & CLK_DIVIDER_HIWORD_MASK) {
437		val = clk_div_mask(divider->width) << (divider->shift + 16);
438	} else {
439		val = clk_div_readl(divider);
440		val &= ~(clk_div_mask(divider->width) << divider->shift);
441	}
442	val |= (u32)value << divider->shift;
443	clk_div_writel(divider, val);
444
445	if (divider->lock)
446		spin_unlock_irqrestore(divider->lock, flags);
447	else
448		__release(divider->lock);
449
450	return 0;
451}
452
453const struct clk_ops clk_divider_ops = {
454	.recalc_rate = clk_divider_recalc_rate,
455	.round_rate = clk_divider_round_rate,
456	.set_rate = clk_divider_set_rate,
457};
458EXPORT_SYMBOL_GPL(clk_divider_ops);
459
460const struct clk_ops clk_divider_ro_ops = {
461	.recalc_rate = clk_divider_recalc_rate,
462	.round_rate = clk_divider_round_rate,
463};
464EXPORT_SYMBOL_GPL(clk_divider_ro_ops);
465
466struct clk_hw *__clk_hw_register_divider(struct device *dev,
467		struct device_node *np, const char *name,
468		const char *parent_name, const struct clk_hw *parent_hw,
469		const struct clk_parent_data *parent_data, unsigned long flags,
470		void __iomem *reg, u8 shift, u8 width, u8 clk_divider_flags,
471		const struct clk_div_table *table, spinlock_t *lock)
 
 
 
 
472{
473	struct clk_divider *div;
474	struct clk_hw *hw;
475	struct clk_init_data init = {};
476	int ret;
477
478	if (clk_divider_flags & CLK_DIVIDER_HIWORD_MASK) {
479		if (width + shift > 16) {
480			pr_warn("divider value exceeds LOWORD field\n");
481			return ERR_PTR(-EINVAL);
482		}
483	}
484
485	/* allocate the divider */
486	div = kzalloc(sizeof(*div), GFP_KERNEL);
487	if (!div)
 
488		return ERR_PTR(-ENOMEM);
 
489
490	init.name = name;
491	if (clk_divider_flags & CLK_DIVIDER_READ_ONLY)
492		init.ops = &clk_divider_ro_ops;
493	else
494		init.ops = &clk_divider_ops;
495	init.flags = flags;
496	init.parent_names = (parent_name ? &parent_name: NULL);
497	init.num_parents = (parent_name ? 1 : 0);
498
499	/* struct clk_divider assignments */
500	div->reg = reg;
501	div->shift = shift;
502	div->width = width;
503	div->flags = clk_divider_flags;
504	div->lock = lock;
505	div->hw.init = &init;
506	div->table = table;
507
508	/* register the clock */
509	hw = &div->hw;
510	ret = clk_hw_register(dev, hw);
511	if (ret) {
512		kfree(div);
513		hw = ERR_PTR(ret);
514	}
515
516	return hw;
517}
518EXPORT_SYMBOL_GPL(__clk_hw_register_divider);
519
520/**
521 * clk_register_divider_table - register a table based divider clock with
522 * the clock framework
523 * @dev: device registering this clock
524 * @name: name of this clock
525 * @parent_name: name of clock's parent
526 * @flags: framework-specific flags
527 * @reg: register address to adjust divider
528 * @shift: number of bits to shift the bitfield
529 * @width: width of the bitfield
530 * @clk_divider_flags: divider-specific flags for this clock
531 * @table: array of divider/value pairs ending with a div set to 0
532 * @lock: shared register lock for this clock
533 */
534struct clk *clk_register_divider_table(struct device *dev, const char *name,
535		const char *parent_name, unsigned long flags,
536		void __iomem *reg, u8 shift, u8 width,
537		u8 clk_divider_flags, const struct clk_div_table *table,
538		spinlock_t *lock)
539{
540	struct clk_hw *hw;
541
542	hw =  __clk_hw_register_divider(dev, NULL, name, parent_name, NULL,
543			NULL, flags, reg, shift, width, clk_divider_flags,
544			table, lock);
545	if (IS_ERR(hw))
546		return ERR_CAST(hw);
547	return hw->clk;
548}
549EXPORT_SYMBOL_GPL(clk_register_divider_table);
550
551void clk_unregister_divider(struct clk *clk)
552{
553	struct clk_divider *div;
554	struct clk_hw *hw;
555
556	hw = __clk_get_hw(clk);
557	if (!hw)
558		return;
559
560	div = to_clk_divider(hw);
561
562	clk_unregister(clk);
563	kfree(div);
564}
565EXPORT_SYMBOL_GPL(clk_unregister_divider);
566
567/**
568 * clk_hw_unregister_divider - unregister a clk divider
569 * @hw: hardware-specific clock data to unregister
570 */
571void clk_hw_unregister_divider(struct clk_hw *hw)
572{
573	struct clk_divider *div;
574
575	div = to_clk_divider(hw);
576
577	clk_hw_unregister(hw);
578	kfree(div);
579}
580EXPORT_SYMBOL_GPL(clk_hw_unregister_divider);