1// SPDX-License-Identifier: GPL-2.0-only
2/*
3 * Copyright (c) 2015 MediaTek Inc.
4 * Author: James Liao <jamesjj.liao@mediatek.com>
5 */
6
7#include <linux/delay.h>
8#include <linux/module.h>
9#include <linux/of_address.h>
10#include <linux/slab.h>
11
12#include "clk-mtk.h"
13
14#define REF2USB_TX_EN		BIT(0)
15#define REF2USB_TX_LPF_EN	BIT(1)
16#define REF2USB_TX_OUT_EN	BIT(2)
17#define REF2USB_EN_MASK		(REF2USB_TX_EN | REF2USB_TX_LPF_EN | \
18				 REF2USB_TX_OUT_EN)
19
20struct mtk_ref2usb_tx {
21	struct clk_hw	hw;
22	void __iomem	*base_addr;
23};
24
25static inline struct mtk_ref2usb_tx *to_mtk_ref2usb_tx(struct clk_hw *hw)
26{
27	return container_of(hw, struct mtk_ref2usb_tx, hw);
28}
29
30static int mtk_ref2usb_tx_is_prepared(struct clk_hw *hw)
31{
32	struct mtk_ref2usb_tx *tx = to_mtk_ref2usb_tx(hw);
33
34	return (readl(tx->base_addr) & REF2USB_EN_MASK) == REF2USB_EN_MASK;
35}
36
37static int mtk_ref2usb_tx_prepare(struct clk_hw *hw)
38{
39	struct mtk_ref2usb_tx *tx = to_mtk_ref2usb_tx(hw);
40	u32 val;
41
42	val = readl(tx->base_addr);
43
44	val |= REF2USB_TX_EN;
45	writel(val, tx->base_addr);
46	udelay(100);
47
48	val |= REF2USB_TX_LPF_EN;
49	writel(val, tx->base_addr);
50
51	val |= REF2USB_TX_OUT_EN;
52	writel(val, tx->base_addr);
53
54	return 0;
55}
56
57static void mtk_ref2usb_tx_unprepare(struct clk_hw *hw)
58{
59	struct mtk_ref2usb_tx *tx = to_mtk_ref2usb_tx(hw);
60	u32 val;
61
62	val = readl(tx->base_addr);
63	val &= ~REF2USB_EN_MASK;
64	writel(val, tx->base_addr);
65}
66
67static const struct clk_ops mtk_ref2usb_tx_ops = {
68	.is_prepared	= mtk_ref2usb_tx_is_prepared,
69	.prepare	= mtk_ref2usb_tx_prepare,
70	.unprepare	= mtk_ref2usb_tx_unprepare,
71};
72
73struct clk_hw *mtk_clk_register_ref2usb_tx(const char *name,
74			const char *parent_name, void __iomem *reg)
75{
76	struct mtk_ref2usb_tx *tx;
77	struct clk_init_data init = {};
78	int ret;
79
80	tx = kzalloc(sizeof(*tx), GFP_KERNEL);
81	if (!tx)
82		return ERR_PTR(-ENOMEM);
83
84	tx->base_addr = reg;
85	tx->hw.init = &init;
86
87	init.name = name;
88	init.ops = &mtk_ref2usb_tx_ops;
89	init.parent_names = &parent_name;
90	init.num_parents = 1;
91
92	ret = clk_hw_register(NULL, &tx->hw);
93
94	if (ret) {
95		kfree(tx);
96		return ERR_PTR(ret);
97	}
98
99	return &tx->hw;
100}
101EXPORT_SYMBOL_GPL(mtk_clk_register_ref2usb_tx);
102
103void mtk_clk_unregister_ref2usb_tx(struct clk_hw *hw)
104{
105	struct mtk_ref2usb_tx *tx = to_mtk_ref2usb_tx(hw);
106
107	clk_hw_unregister(hw);
108	kfree(tx);
109}
110EXPORT_SYMBOL_GPL(mtk_clk_unregister_ref2usb_tx);
111
112MODULE_LICENSE("GPL");
113