linux/drivers/clk/mediatek/clk-apmixed.c
AngeloGioacchino Del Regno b7520e2d4e clk: mediatek: clk-apmixed: Add helper function to unregister ref2usb_tx
The ref2usb_tx clock was introduced a long time ago and, at that time,
the MediaTek clock drivers were using CLK_OF_DECLARE, so they would
never unregister.

Nowadays, unregistering clock drivers is a thing, as we're registering
them as platform_driver and allowing them to be kernel modules: add a
helper function to cleanup the ref2usb_tx clock during error handling
and upon module removal.

Signed-off-by: AngeloGioacchino Del Regno <angelogioacchino.delregno@collabora.com>
Reviewed-by: Chen-Yu Tsai <wenst@chromium.org>
Link: https://lore.kernel.org/r/20220921091455.41327-8-angelogioacchino.delregno@collabora.com
Signed-off-by: Chen-Yu Tsai <wenst@chromium.org>
2022-09-26 11:13:09 +08:00

113 lines
2.3 KiB
C

// SPDX-License-Identifier: GPL-2.0-only
/*
* Copyright (c) 2015 MediaTek Inc.
* Author: James Liao <jamesjj.liao@mediatek.com>
*/
#include <linux/delay.h>
#include <linux/module.h>
#include <linux/of_address.h>
#include <linux/slab.h>
#include "clk-mtk.h"
#define REF2USB_TX_EN BIT(0)
#define REF2USB_TX_LPF_EN BIT(1)
#define REF2USB_TX_OUT_EN BIT(2)
#define REF2USB_EN_MASK (REF2USB_TX_EN | REF2USB_TX_LPF_EN | \
REF2USB_TX_OUT_EN)
struct mtk_ref2usb_tx {
struct clk_hw hw;
void __iomem *base_addr;
};
static inline struct mtk_ref2usb_tx *to_mtk_ref2usb_tx(struct clk_hw *hw)
{
return container_of(hw, struct mtk_ref2usb_tx, hw);
}
static int mtk_ref2usb_tx_is_prepared(struct clk_hw *hw)
{
struct mtk_ref2usb_tx *tx = to_mtk_ref2usb_tx(hw);
return (readl(tx->base_addr) & REF2USB_EN_MASK) == REF2USB_EN_MASK;
}
static int mtk_ref2usb_tx_prepare(struct clk_hw *hw)
{
struct mtk_ref2usb_tx *tx = to_mtk_ref2usb_tx(hw);
u32 val;
val = readl(tx->base_addr);
val |= REF2USB_TX_EN;
writel(val, tx->base_addr);
udelay(100);
val |= REF2USB_TX_LPF_EN;
writel(val, tx->base_addr);
val |= REF2USB_TX_OUT_EN;
writel(val, tx->base_addr);
return 0;
}
static void mtk_ref2usb_tx_unprepare(struct clk_hw *hw)
{
struct mtk_ref2usb_tx *tx = to_mtk_ref2usb_tx(hw);
u32 val;
val = readl(tx->base_addr);
val &= ~REF2USB_EN_MASK;
writel(val, tx->base_addr);
}
static const struct clk_ops mtk_ref2usb_tx_ops = {
.is_prepared = mtk_ref2usb_tx_is_prepared,
.prepare = mtk_ref2usb_tx_prepare,
.unprepare = mtk_ref2usb_tx_unprepare,
};
struct clk_hw *mtk_clk_register_ref2usb_tx(const char *name,
const char *parent_name, void __iomem *reg)
{
struct mtk_ref2usb_tx *tx;
struct clk_init_data init = {};
int ret;
tx = kzalloc(sizeof(*tx), GFP_KERNEL);
if (!tx)
return ERR_PTR(-ENOMEM);
tx->base_addr = reg;
tx->hw.init = &init;
init.name = name;
init.ops = &mtk_ref2usb_tx_ops;
init.parent_names = &parent_name;
init.num_parents = 1;
ret = clk_hw_register(NULL, &tx->hw);
if (ret) {
kfree(tx);
return ERR_PTR(ret);
}
return &tx->hw;
}
EXPORT_SYMBOL_GPL(mtk_clk_register_ref2usb_tx);
void mtk_clk_unregister_ref2usb_tx(struct clk_hw *hw)
{
struct mtk_ref2usb_tx *tx = to_mtk_ref2usb_tx(hw);
clk_hw_unregister(hw);
kfree(tx);
}
EXPORT_SYMBOL_GPL(mtk_clk_unregister_ref2usb_tx);
MODULE_LICENSE("GPL");