drivers/clk/mediatek/clk-apmixed.c

   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");