xref: /openbmc/linux/drivers/clk/sunxi/clk-a10-hosc.c (revision 35267cea)
1 // SPDX-License-Identifier: GPL-2.0-or-later
2 /*
3  * Copyright 2013 Emilio López
4  *
5  * Emilio López <emilio@elopez.com.ar>
6  */
7 
8 #include <linux/clk-provider.h>
9 #include <linux/of.h>
10 #include <linux/of_address.h>
11 #include <linux/slab.h>
12 
13 #define SUNXI_OSC24M_GATE	0
14 
15 static DEFINE_SPINLOCK(hosc_lock);
16 
17 static void __init sun4i_osc_clk_setup(struct device_node *node)
18 {
19 	struct clk *clk;
20 	struct clk_fixed_rate *fixed;
21 	struct clk_gate *gate;
22 	const char *clk_name = node->name;
23 	u32 rate;
24 
25 	if (of_property_read_u32(node, "clock-frequency", &rate))
26 		return;
27 
28 	/* allocate fixed-rate and gate clock structs */
29 	fixed = kzalloc(sizeof(struct clk_fixed_rate), GFP_KERNEL);
30 	if (!fixed)
31 		return;
32 	gate = kzalloc(sizeof(struct clk_gate), GFP_KERNEL);
33 	if (!gate)
34 		goto err_free_fixed;
35 
36 	of_property_read_string(node, "clock-output-names", &clk_name);
37 
38 	/* set up gate and fixed rate properties */
39 	gate->reg = of_iomap(node, 0);
40 	gate->bit_idx = SUNXI_OSC24M_GATE;
41 	gate->lock = &hosc_lock;
42 	fixed->fixed_rate = rate;
43 
44 	clk = clk_register_composite(NULL, clk_name,
45 			NULL, 0,
46 			NULL, NULL,
47 			&fixed->hw, &clk_fixed_rate_ops,
48 			&gate->hw, &clk_gate_ops, 0);
49 
50 	if (IS_ERR(clk))
51 		goto err_free_gate;
52 
53 	of_clk_add_provider(node, of_clk_src_simple_get, clk);
54 
55 	return;
56 
57 err_free_gate:
58 	kfree(gate);
59 err_free_fixed:
60 	kfree(fixed);
61 }
62 CLK_OF_DECLARE(sun4i_osc, "allwinner,sun4i-a10-osc-clk", sun4i_osc_clk_setup);
63