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1// SPDX-License-Identifier: GPL-2.0-only2/*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