1*4882a593Smuzhiyun /*
2*4882a593Smuzhiyun * Copyright (C) 2012 ST Microelectronics
3*4882a593Smuzhiyun * Viresh Kumar <vireshk@kernel.org>
4*4882a593Smuzhiyun *
5*4882a593Smuzhiyun * This file is licensed under the terms of the GNU General Public
6*4882a593Smuzhiyun * License version 2. This program is licensed "as is" without any
7*4882a593Smuzhiyun * warranty of any kind, whether express or implied.
8*4882a593Smuzhiyun *
9*4882a593Smuzhiyun * SPEAr clk - Common routines
10*4882a593Smuzhiyun */
11*4882a593Smuzhiyun
12*4882a593Smuzhiyun #include <linux/clk-provider.h>
13*4882a593Smuzhiyun #include <linux/types.h>
14*4882a593Smuzhiyun #include "clk.h"
15*4882a593Smuzhiyun
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*4882a593Smuzhiyun long clk_round_rate_index(struct clk_hw *hw, unsigned long drate,
17*4882a593Smuzhiyun unsigned long parent_rate, clk_calc_rate calc_rate, u8 rtbl_cnt,
18*4882a593Smuzhiyun int *index)
19*4882a593Smuzhiyun {
20*4882a593Smuzhiyun unsigned long prev_rate, rate = 0;
21*4882a593Smuzhiyun
22*4882a593Smuzhiyun for (*index = 0; *index < rtbl_cnt; (*index)++) {
23*4882a593Smuzhiyun prev_rate = rate;
24*4882a593Smuzhiyun rate = calc_rate(hw, parent_rate, *index);
25*4882a593Smuzhiyun if (drate < rate) {
26*4882a593Smuzhiyun /* previous clock was best */
27*4882a593Smuzhiyun if (*index) {
28*4882a593Smuzhiyun rate = prev_rate;
29*4882a593Smuzhiyun (*index)--;
30*4882a593Smuzhiyun }
31*4882a593Smuzhiyun break;
32*4882a593Smuzhiyun }
33*4882a593Smuzhiyun }
34*4882a593Smuzhiyun
35*4882a593Smuzhiyun if ((*index) == rtbl_cnt)
36*4882a593Smuzhiyun (*index)--;
37*4882a593Smuzhiyun
38*4882a593Smuzhiyun return rate;
39*4882a593Smuzhiyun }
40