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
20 struct mtk_ref2usb_tx {
21 struct clk_hw hw;
22 void __iomem *base_addr;
23 };
24
to_mtk_ref2usb_tx(struct clk_hw * hw)25 static 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
mtk_ref2usb_tx_is_prepared(struct clk_hw * hw)30 static 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
mtk_ref2usb_tx_prepare(struct clk_hw * hw)37 static 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
mtk_ref2usb_tx_unprepare(struct clk_hw * hw)57 static 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
67 static 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
mtk_clk_register_ref2usb_tx(const char * name,const char * parent_name,void __iomem * reg)73 struct 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 }
101 EXPORT_SYMBOL_GPL(mtk_clk_register_ref2usb_tx);
102
mtk_clk_unregister_ref2usb_tx(struct clk_hw * hw)103 void 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 }
110 EXPORT_SYMBOL_GPL(mtk_clk_unregister_ref2usb_tx);
111
112 MODULE_LICENSE("GPL");
113