1 /*
2  * Clock driver for the ARM Integrator/IM-PD1 board
3  * Copyright (C) 2012 Linus Walleij
4  *
5  * This program is free software; you can redistribute it and/or modify
6  * it under the terms of the GNU General Public License version 2 as
7  * published by the Free Software Foundation.
8  */
9 #include <linux/clk-provider.h>
10 #include <linux/clk.h>
11 #include <linux/clkdev.h>
12 #include <linux/err.h>
13 #include <linux/io.h>
14 #include <linux/platform_data/clk-integrator.h>
15 
16 #include <mach/impd1.h>
17 
18 #include "clk-icst.h"
19 
20 struct impd1_clk {
21 	struct clk *vcoclk;
22 	struct clk *uartclk;
23 	struct clk_lookup *clks[3];
24 };
25 
26 static struct impd1_clk impd1_clks[4];
27 
28 /*
29  * There are two VCO's on the IM-PD1 but only one is used by the
30  * kernel, that is why we are only implementing the control of
31  * IMPD1_OSC1 here.
32  */
33 
34 static const struct icst_params impd1_vco_params = {
35 	.ref		= 24000000,	/* 24 MHz */
36 	.vco_max	= ICST525_VCO_MAX_3V,
37 	.vco_min	= ICST525_VCO_MIN,
38 	.vd_min		= 12,
39 	.vd_max		= 519,
40 	.rd_min		= 3,
41 	.rd_max		= 120,
42 	.s2div		= icst525_s2div,
43 	.idx2s		= icst525_idx2s,
44 };
45 
46 static const struct clk_icst_desc impd1_icst1_desc = {
47 	.params = &impd1_vco_params,
48 	.vco_offset = IMPD1_OSC1,
49 	.lock_offset = IMPD1_LOCK,
50 };
51 
52 /**
53  * integrator_impd1_clk_init() - set up the integrator clock tree
54  * @base: base address of the logic module (LM)
55  * @id: the ID of this LM
56  */
57 void integrator_impd1_clk_init(void __iomem *base, unsigned int id)
58 {
59 	struct impd1_clk *imc;
60 	struct clk *clk;
61 	int i;
62 
63 	if (id > 3) {
64 		pr_crit("no more than 4 LMs can be attached\n");
65 		return;
66 	}
67 	imc = &impd1_clks[id];
68 
69 	clk = icst_clk_register(NULL, &impd1_icst1_desc, base);
70 	imc->vcoclk = clk;
71 	imc->clks[0] = clkdev_alloc(clk, NULL, "lm%x:01000", id);
72 
73 	/* UART reference clock */
74 	clk = clk_register_fixed_rate(NULL, "uartclk", NULL, CLK_IS_ROOT,
75 				14745600);
76 	imc->uartclk = clk;
77 	imc->clks[1] = clkdev_alloc(clk, NULL, "lm%x:00100", id);
78 	imc->clks[2] = clkdev_alloc(clk, NULL, "lm%x:00200", id);
79 
80 	for (i = 0; i < ARRAY_SIZE(imc->clks); i++)
81 		clkdev_add(imc->clks[i]);
82 }
83 
84 void integrator_impd1_clk_exit(unsigned int id)
85 {
86 	int i;
87 	struct impd1_clk *imc;
88 
89 	if (id > 3)
90 		return;
91 	imc = &impd1_clks[id];
92 
93 	for (i = 0; i < ARRAY_SIZE(imc->clks); i++)
94 		clkdev_drop(imc->clks[i]);
95 	clk_unregister(imc->uartclk);
96 	clk_unregister(imc->vcoclk);
97 }
98