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 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 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 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 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 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); 102 103 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