xref: /openbmc/linux/drivers/clk/sprd/div.c (revision 842ed298)
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 long sprd_div_helper_round_rate(struct sprd_clk_common *common,
13 				const struct sprd_div_internal *div,
14 				unsigned long rate,
15 				unsigned long *parent_rate)
16 {
17 	return divider_round_rate(&common->hw, rate, parent_rate,
18 				  NULL, div->width, 0);
19 }
20 EXPORT_SYMBOL_GPL(sprd_div_helper_round_rate);
21 
22 static long sprd_div_round_rate(struct clk_hw *hw, unsigned long rate,
23 				unsigned long *parent_rate)
24 {
25 	struct sprd_div *cd = hw_to_sprd_div(hw);
26 
27 	return sprd_div_helper_round_rate(&cd->common, &cd->div,
28 					  rate, parent_rate);
29 }
30 
31 unsigned long sprd_div_helper_recalc_rate(struct sprd_clk_common *common,
32 					  const struct sprd_div_internal *div,
33 					  unsigned long parent_rate)
34 {
35 	unsigned long val;
36 	unsigned int reg;
37 
38 	regmap_read(common->regmap, common->reg, &reg);
39 	val = reg >> div->shift;
40 	val &= (1 << div->width) - 1;
41 
42 	return divider_recalc_rate(&common->hw, parent_rate, val, NULL, 0,
43 				   div->width);
44 }
45 EXPORT_SYMBOL_GPL(sprd_div_helper_recalc_rate);
46 
47 static unsigned long sprd_div_recalc_rate(struct clk_hw *hw,
48 					  unsigned long parent_rate)
49 {
50 	struct sprd_div *cd = hw_to_sprd_div(hw);
51 
52 	return sprd_div_helper_recalc_rate(&cd->common, &cd->div, parent_rate);
53 }
54 
55 int sprd_div_helper_set_rate(const struct sprd_clk_common *common,
56 			     const struct sprd_div_internal *div,
57 			     unsigned long rate,
58 			     unsigned long parent_rate)
59 {
60 	unsigned long val;
61 	unsigned int reg;
62 
63 	val = divider_get_val(rate, parent_rate, NULL,
64 			      div->width, 0);
65 
66 	regmap_read(common->regmap, common->reg, &reg);
67 	reg &= ~GENMASK(div->width + div->shift - 1, div->shift);
68 
69 	regmap_write(common->regmap, common->reg,
70 			  reg | (val << div->shift));
71 
72 	return 0;
73 
74 }
75 EXPORT_SYMBOL_GPL(sprd_div_helper_set_rate);
76 
77 static int sprd_div_set_rate(struct clk_hw *hw, unsigned long rate,
78 			     unsigned long parent_rate)
79 {
80 	struct sprd_div *cd = hw_to_sprd_div(hw);
81 
82 	return sprd_div_helper_set_rate(&cd->common, &cd->div,
83 					rate, parent_rate);
84 }
85 
86 const struct clk_ops sprd_div_ops = {
87 	.recalc_rate = sprd_div_recalc_rate,
88 	.round_rate = sprd_div_round_rate,
89 	.set_rate = sprd_div_set_rate,
90 };
91 EXPORT_SYMBOL_GPL(sprd_div_ops);
92