2 * This program is free software; you can redistribute it and/or modify
3 * it under the terms of the GNU General Public License version 2 as
4 * published by the Free Software Foundation.
6 * This program is distributed in the hope that it will be useful,
7 * but WITHOUT ANY WARRANTY; without even the implied warranty of
8 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
9 * GNU General Public License for more details.
11 * Copyright (C) 2012 ARM Limited
14 #include <linux/clkdev.h>
15 #include <linux/clk-provider.h>
16 #include <linux/err.h>
18 #include <linux/platform_device.h>
19 #include <linux/slab.h>
20 #include <linux/vexpress.h>
25 unsigned long rate_min
;
26 unsigned long rate_max
;
29 #define to_vexpress_osc(osc) container_of(osc, struct vexpress_osc, hw)
31 static unsigned long vexpress_osc_recalc_rate(struct clk_hw
*hw
,
32 unsigned long parent_rate
)
34 struct vexpress_osc
*osc
= to_vexpress_osc(hw
);
37 regmap_read(osc
->reg
, 0, &rate
);
42 static long vexpress_osc_round_rate(struct clk_hw
*hw
, unsigned long rate
,
43 unsigned long *parent_rate
)
45 struct vexpress_osc
*osc
= to_vexpress_osc(hw
);
47 if (WARN_ON(osc
->rate_min
&& rate
< osc
->rate_min
))
50 if (WARN_ON(osc
->rate_max
&& rate
> osc
->rate_max
))
56 static int vexpress_osc_set_rate(struct clk_hw
*hw
, unsigned long rate
,
57 unsigned long parent_rate
)
59 struct vexpress_osc
*osc
= to_vexpress_osc(hw
);
61 return regmap_write(osc
->reg
, 0, rate
);
64 static struct clk_ops vexpress_osc_ops
= {
65 .recalc_rate
= vexpress_osc_recalc_rate
,
66 .round_rate
= vexpress_osc_round_rate
,
67 .set_rate
= vexpress_osc_set_rate
,
71 static int vexpress_osc_probe(struct platform_device
*pdev
)
73 struct clk_lookup
*cl
= pdev
->dev
.platform_data
; /* Non-DT lookup */
74 struct clk_init_data init
;
75 struct vexpress_osc
*osc
;
79 osc
= devm_kzalloc(&pdev
->dev
, sizeof(*osc
), GFP_KERNEL
);
83 osc
->reg
= devm_regmap_init_vexpress_config(&pdev
->dev
);
85 return PTR_ERR(osc
->reg
);
87 if (of_property_read_u32_array(pdev
->dev
.of_node
, "freq-range", range
,
88 ARRAY_SIZE(range
)) == 0) {
89 osc
->rate_min
= range
[0];
90 osc
->rate_max
= range
[1];
93 if (of_property_read_string(pdev
->dev
.of_node
, "clock-output-names",
95 init
.name
= dev_name(&pdev
->dev
);
97 init
.ops
= &vexpress_osc_ops
;
98 init
.flags
= CLK_IS_ROOT
;
101 osc
->hw
.init
= &init
;
103 clk
= clk_register(NULL
, &osc
->hw
);
107 of_clk_add_provider(pdev
->dev
.of_node
, of_clk_src_simple_get
, clk
);
109 /* Only happens for non-DT cases */
115 dev_dbg(&pdev
->dev
, "Registered clock '%s'\n", init
.name
);
120 static struct of_device_id vexpress_osc_of_match
[] = {
121 { .compatible
= "arm,vexpress-osc", },
125 static struct platform_driver vexpress_osc_driver
= {
127 .name
= "vexpress-osc",
128 .of_match_table
= vexpress_osc_of_match
,
130 .probe
= vexpress_osc_probe
,
133 static int __init
vexpress_osc_init(void)
135 return platform_driver_register(&vexpress_osc_driver
);
137 core_initcall(vexpress_osc_init
);