1 /*
2 * Copyright (C) 2012 ST Microelectronics
3 * Viresh Kumar <vireshk@kernel.org>
4 *
5 * This file is licensed under the terms of the GNU General Public
6 * License version 2. This program is licensed "as is" without any
7 * warranty of any kind, whether express or implied.
8 *
9 * SPEAr clk - Common routines
10 */
11
12 #include <linux/clk-provider.h>
13 #include <linux/types.h>
14 #include "clk.h"
15
clk_round_rate_index(struct clk_hw * hw,unsigned long drate,unsigned long parent_rate,clk_calc_rate calc_rate,u8 rtbl_cnt,int * index)16 long clk_round_rate_index(struct clk_hw *hw, unsigned long drate,
17 unsigned long parent_rate, clk_calc_rate calc_rate, u8 rtbl_cnt,
18 int *index)
19 {
20 unsigned long prev_rate, rate = 0;
21
22 for (*index = 0; *index < rtbl_cnt; (*index)++) {
23 prev_rate = rate;
24 rate = calc_rate(hw, parent_rate, *index);
25 if (drate < rate) {
26 /* previous clock was best */
27 if (*index) {
28 rate = prev_rate;
29 (*index)--;
30 }
31 break;
32 }
33 }
34
35 if ((*index) == rtbl_cnt)
36 (*index)--;
37
38 return rate;
39 }
40