xref: /linux/drivers/clk/sprd/div.c (revision 019b383d1132e4051de0d2e43254454b86538cf4)
1 // SPDX-License-Identifier: GPL-2.0
2 //
3 // Spreadtrum divider clock driver
4 //
5 // Copyright (C) 2017 Spreadtrum, Inc.
6 // Author: Chunyan Zhang <chunyan.zhang@spreadtrum.com>
7 
8 #include <linux/clk-provider.h>
9 
10 #include "div.h"
11 
12 static long sprd_div_round_rate(struct clk_hw *hw, unsigned long rate,
13 				unsigned long *parent_rate)
14 {
15 	struct sprd_div *cd = hw_to_sprd_div(hw);
16 
17 	return divider_round_rate(&cd->common.hw, rate, parent_rate, NULL,
18 				  cd->div.width, 0);
19 }
20 
21 unsigned long sprd_div_helper_recalc_rate(struct sprd_clk_common *common,
22 					  const struct sprd_div_internal *div,
23 					  unsigned long parent_rate)
24 {
25 	unsigned long val;
26 	unsigned int reg;
27 
28 	regmap_read(common->regmap, common->reg, &reg);
29 	val = reg >> div->shift;
30 	val &= (1 << div->width) - 1;
31 
32 	return divider_recalc_rate(&common->hw, parent_rate, val, NULL, 0,
33 				   div->width);
34 }
35 EXPORT_SYMBOL_GPL(sprd_div_helper_recalc_rate);
36 
37 static unsigned long sprd_div_recalc_rate(struct clk_hw *hw,
38 					  unsigned long parent_rate)
39 {
40 	struct sprd_div *cd = hw_to_sprd_div(hw);
41 
42 	return sprd_div_helper_recalc_rate(&cd->common, &cd->div, parent_rate);
43 }
44 
45 int sprd_div_helper_set_rate(const struct sprd_clk_common *common,
46 			     const struct sprd_div_internal *div,
47 			     unsigned long rate,
48 			     unsigned long parent_rate)
49 {
50 	unsigned long val;
51 	unsigned int reg;
52 
53 	val = divider_get_val(rate, parent_rate, NULL,
54 			      div->width, 0);
55 
56 	regmap_read(common->regmap, common->reg, &reg);
57 	reg &= ~GENMASK(div->width + div->shift - 1, div->shift);
58 
59 	regmap_write(common->regmap, common->reg,
60 			  reg | (val << div->shift));
61 
62 	return 0;
63 
64 }
65 EXPORT_SYMBOL_GPL(sprd_div_helper_set_rate);
66 
67 static int sprd_div_set_rate(struct clk_hw *hw, unsigned long rate,
68 			     unsigned long parent_rate)
69 {
70 	struct sprd_div *cd = hw_to_sprd_div(hw);
71 
72 	return sprd_div_helper_set_rate(&cd->common, &cd->div,
73 					rate, parent_rate);
74 }
75 
76 const struct clk_ops sprd_div_ops = {
77 	.recalc_rate = sprd_div_recalc_rate,
78 	.round_rate = sprd_div_round_rate,
79 	.set_rate = sprd_div_set_rate,
80 };
81 EXPORT_SYMBOL_GPL(sprd_div_ops);
82