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(addr: 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(addr: tx->base_addr);
43
44 val |= REF2USB_TX_EN;
45 writel(val, addr: tx->base_addr);
46 udelay(usec: 100);
47
48 val |= REF2USB_TX_LPF_EN;
49 writel(val, addr: tx->base_addr);
50
51 val |= REF2USB_TX_OUT_EN;
52 writel(val, addr: 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(addr: tx->base_addr);
63 val &= ~REF2USB_EN_MASK;
64 writel(val, addr: 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(error: -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, hw: &tx->hw);
93
94 if (ret) {
95 kfree(objp: tx);
96 return ERR_PTR(error: 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(objp: tx);
109}
110EXPORT_SYMBOL_GPL(mtk_clk_unregister_ref2usb_tx);
111
112MODULE_LICENSE("GPL");
113

source code of linux/drivers/clk/mediatek/clk-apmixed.c