xref: /openbmc/linux/drivers/clk/pxa/clk-pxa.c (revision 8684014d)
1 /*
2  * Marvell PXA family clocks
3  *
4  * Copyright (C) 2014 Robert Jarzmik
5  *
6  * Common clock code for PXA clocks ("CKEN" type clocks + DT)
7  *
8  * This program is free software; you can redistribute it and/or modify
9  * it under the terms of the GNU General Public License as published by
10  * the Free Software Foundation; version 2 of the License.
11  *
12  */
13 #include <linux/clk.h>
14 #include <linux/clk-provider.h>
15 #include <linux/clkdev.h>
16 #include <linux/of.h>
17 
18 #include <dt-bindings/clock/pxa-clock.h>
19 #include "clk-pxa.h"
20 
21 DEFINE_SPINLOCK(lock);
22 
23 static struct clk *pxa_clocks[CLK_MAX];
24 static struct clk_onecell_data onecell_data = {
25 	.clks = pxa_clocks,
26 	.clk_num = CLK_MAX,
27 };
28 
29 struct pxa_clk {
30 	struct clk_hw hw;
31 	struct clk_fixed_factor lp;
32 	struct clk_fixed_factor hp;
33 	struct clk_gate gate;
34 	bool (*is_in_low_power)(void);
35 };
36 
37 #define to_pxa_clk(_hw) container_of(_hw, struct pxa_clk, hw)
38 
39 static unsigned long cken_recalc_rate(struct clk_hw *hw,
40 				      unsigned long parent_rate)
41 {
42 	struct pxa_clk *pclk = to_pxa_clk(hw);
43 	struct clk_fixed_factor *fix;
44 
45 	if (!pclk->is_in_low_power || pclk->is_in_low_power())
46 		fix = &pclk->lp;
47 	else
48 		fix = &pclk->hp;
49 	fix->hw.clk = hw->clk;
50 	return clk_fixed_factor_ops.recalc_rate(&fix->hw, parent_rate);
51 }
52 
53 static struct clk_ops cken_rate_ops = {
54 	.recalc_rate = cken_recalc_rate,
55 };
56 
57 static u8 cken_get_parent(struct clk_hw *hw)
58 {
59 	struct pxa_clk *pclk = to_pxa_clk(hw);
60 
61 	if (!pclk->is_in_low_power)
62 		return 0;
63 	return pclk->is_in_low_power() ? 0 : 1;
64 }
65 
66 static struct clk_ops cken_mux_ops = {
67 	.get_parent = cken_get_parent,
68 	.set_parent = dummy_clk_set_parent,
69 };
70 
71 void __init clkdev_pxa_register(int ckid, const char *con_id,
72 				const char *dev_id, struct clk *clk)
73 {
74 	if (!IS_ERR(clk) && (ckid != CLK_NONE))
75 		pxa_clocks[ckid] = clk;
76 	if (!IS_ERR(clk))
77 		clk_register_clkdev(clk, con_id, dev_id);
78 }
79 
80 int __init clk_pxa_cken_init(const struct desc_clk_cken *clks, int nb_clks)
81 {
82 	int i;
83 	struct pxa_clk *pxa_clk;
84 	struct clk *clk;
85 
86 	for (i = 0; i < nb_clks; i++) {
87 		pxa_clk = kzalloc(sizeof(*pxa_clk), GFP_KERNEL);
88 		pxa_clk->is_in_low_power = clks[i].is_in_low_power;
89 		pxa_clk->lp = clks[i].lp;
90 		pxa_clk->hp = clks[i].hp;
91 		pxa_clk->gate = clks[i].gate;
92 		pxa_clk->gate.lock = &lock;
93 		clk = clk_register_composite(NULL, clks[i].name,
94 					     clks[i].parent_names, 2,
95 					     &pxa_clk->hw, &cken_mux_ops,
96 					     &pxa_clk->hw, &cken_rate_ops,
97 					     &pxa_clk->gate.hw, &clk_gate_ops,
98 					     clks[i].flags);
99 		clkdev_pxa_register(clks[i].ckid, clks[i].con_id,
100 				    clks[i].dev_id, clk);
101 	}
102 	return 0;
103 }
104 
105 void __init clk_pxa_dt_common_init(struct device_node *np)
106 {
107 	of_clk_add_provider(np, of_clk_src_onecell_get, &onecell_data);
108 }
109