clk-impd1.c

  1// SPDX-License-Identifier: GPL-2.0-only
  2/*
  3 * Clock driver for the ARM Integrator/IM-PD1 board
  4 * Copyright (C) 2012-2013 Linus Walleij
  5 */
  6#include <linux/clk-provider.h>
  7#include <linux/clkdev.h>
  8#include <linux/err.h>
  9#include <linux/io.h>
 10#include <linux/platform_device.h>
 11#include <linux/module.h>
 12#include <linux/mfd/syscon.h>
 13#include <linux/regmap.h>
 14
 15#include "icst.h"
 16#include "clk-icst.h"
 17
 18#define IMPD1_OSC1	0x00
 19#define IMPD1_OSC2	0x04
 20#define IMPD1_LOCK	0x08
 21
 22/*
 23 * There are two VCO's on the IM-PD1
 24 */
 25
 26static const struct icst_params impd1_vco1_params = {
 27	.ref		= 24000000,	/* 24 MHz */
 28	.vco_max	= ICST525_VCO_MAX_3V,
 29	.vco_min	= ICST525_VCO_MIN,
 30	.vd_min		= 12,
 31	.vd_max		= 519,
 32	.rd_min		= 3,
 33	.rd_max		= 120,
 34	.s2div		= icst525_s2div,
 35	.idx2s		= icst525_idx2s,
 36};
 37
 38static const struct clk_icst_desc impd1_icst1_desc = {
 39	.params = &impd1_vco1_params,
 40	.vco_offset = IMPD1_OSC1,
 41	.lock_offset = IMPD1_LOCK,
 42};
 43
 44static const struct icst_params impd1_vco2_params = {
 45	.ref		= 24000000,	/* 24 MHz */
 46	.vco_max	= ICST525_VCO_MAX_3V,
 47	.vco_min	= ICST525_VCO_MIN,
 48	.vd_min		= 12,
 49	.vd_max		= 519,
 50	.rd_min		= 3,
 51	.rd_max		= 120,
 52	.s2div		= icst525_s2div,
 53	.idx2s		= icst525_idx2s,
 54};
 55
 56static const struct clk_icst_desc impd1_icst2_desc = {
 57	.params = &impd1_vco2_params,
 58	.vco_offset = IMPD1_OSC2,
 59	.lock_offset = IMPD1_LOCK,
 60};
 61
 62static int integrator_impd1_clk_spawn(struct device *dev,
 63				      struct device_node *parent,
 64				      struct device_node *np)
 65{
 66	struct regmap *map;
 67	struct clk *clk = ERR_PTR(-EINVAL);
 68	const char *name = np->name;
 69	const char *parent_name;
 70	const struct clk_icst_desc *desc;
 71	int ret;
 72
 73	map = syscon_node_to_regmap(parent);
 74	if (IS_ERR(map)) {
 75		pr_err("no regmap for syscon IM-PD1 ICST clock parent\n");
 76		return PTR_ERR(map);
 77	}
 78
 79	if (of_device_is_compatible(np, "arm,impd1-vco1")) {
 80		desc = &impd1_icst1_desc;
 81	} else if (of_device_is_compatible(np, "arm,impd1-vco2")) {
 82		desc = &impd1_icst2_desc;
 83	} else {
 84		dev_err(dev, "not a clock node %s\n", name);
 85		return -ENODEV;
 86	}
 87
 88	of_property_read_string(np, "clock-output-names", &name);
 89	parent_name = of_clk_get_parent_name(np, 0);
 90	clk = icst_clk_setup(NULL, desc, name, parent_name, map,
 91			     ICST_INTEGRATOR_IM_PD1);
 92	if (!IS_ERR(clk)) {
 93		of_clk_add_provider(np, of_clk_src_simple_get, clk);
 94		ret = 0;
 95	} else {
 96		dev_err(dev, "error setting up IM-PD1 ICST clock\n");
 97		ret = PTR_ERR(clk);
 98	}
 99
100	return ret;
101}
102
103static int integrator_impd1_clk_probe(struct platform_device *pdev)
104{
105	struct device *dev = &pdev->dev;
106	struct device_node *np = dev->of_node;
107	struct device_node *child;
108	int ret = 0;
109
110	for_each_available_child_of_node(np, child) {
111		ret = integrator_impd1_clk_spawn(dev, np, child);
112		if (ret) {
113			of_node_put(child);
114			break;
115		}
116	}
117
118	return ret;
119}
120
121static const struct of_device_id impd1_syscon_match[] = {
122	{ .compatible = "arm,im-pd1-syscon", },
123	{}
124};
125MODULE_DEVICE_TABLE(of, impd1_syscon_match);
126
127static struct platform_driver impd1_clk_driver = {
128	.driver = {
129		.name = "impd1-clk",
130		.of_match_table = impd1_syscon_match,
131	},
132	.probe  = integrator_impd1_clk_probe,
133};
134builtin_platform_driver(impd1_clk_driver);
135
136MODULE_AUTHOR("Linus Walleij <linusw@kernel.org>");
137MODULE_DESCRIPTION("Arm IM-PD1 module clock driver");
138MODULE_LICENSE("GPL v2");