Re: [PATCH v14 06/11] clk: realtek: Add support for gate clock

[Jerome Brunet <jbrunet@baylibre.com>]

On 2026-09-01 15:24 +0800, Yu-Chun Lin wrote:
> From: Cheng-Yu Lee <cylee12@realtek.com>
> 
> Introduce clk_regmap_gate_ops supporting enable, disable, is_enabled, and
> for standard regmap gate clocks.
> 
> Add clk_regmap_gate_ro_ops as a read-only variant exposing only is_enabled.
> 
> Signed-off-by: Cheng-Yu Lee <cylee12@realtek.com>
> Co-developed-by: Yu-Chun Lin <eleanor.lin@realtek.com>
> Reviewed-by: Brian Masney <bmasney@redhat.com>
> Signed-off-by: Yu-Chun Lin <eleanor.lin@realtek.com>
> ---
> Changes in v14:
> - Move Reviewed-by tag to the correct position.
> ---
>  drivers/clk/realtek/Makefile          |  1 +
>  drivers/clk/realtek/clk-regmap-gate.c | 70 +++++++++++++++++++++++++++
>  drivers/clk/realtek/clk-regmap-gate.h | 65 +++++++++++++++++++++++++
>  3 files changed, 136 insertions(+)
>  create mode 100644 drivers/clk/realtek/clk-regmap-gate.c
>  create mode 100644 drivers/clk/realtek/clk-regmap-gate.h
> 
> diff --git a/drivers/clk/realtek/Makefile b/drivers/clk/realtek/Makefile
> index 71edc18121c6..840aff067b61 100644
> --- a/drivers/clk/realtek/Makefile
> +++ b/drivers/clk/realtek/Makefile
> @@ -3,4 +3,5 @@ obj-$(CONFIG_RTK_CLK_COMMON) += clk-rtk.o
>  
>  clk-rtk-y += clk-rtk-common.o
>  clk-rtk-y += clk-pll.o
> +clk-rtk-y += clk-regmap-gate.o
>  clk-rtk-y += freq_table.o
> diff --git a/drivers/clk/realtek/clk-regmap-gate.c b/drivers/clk/realtek/clk-regmap-gate.c
> new file mode 100644
> index 000000000000..1c32a87d97df
> --- /dev/null
> +++ b/drivers/clk/realtek/clk-regmap-gate.c
> @@ -0,0 +1,70 @@
> +// SPDX-License-Identifier: GPL-2.0-only
> +/*
> + * Copyright (C) 2017-2026 Realtek Semiconductor Corporation
> + * Author: Cheng-Yu Lee <cylee12@realtek.com>
> + */
> +
> +#include <linux/bits.h>
> +#include <linux/clk-provider.h>
> +#include <linux/export.h>
> +#include <linux/regmap.h>
> +#include "clk-regmap-gate.h"
> +
> +static int rtk_clk_regmap_gate_enable(struct clk_hw *hw)
> +{
> +	struct rtk_clk_regmap_gate *clkg = to_rtk_clk_regmap_gate(hw);
> +	unsigned int mask;
> +	unsigned int val;
> +
> +	mask = BIT(clkg->bit_idx);
> +	val = BIT(clkg->bit_idx);
> +
> +	if (clkg->write_en) {
> +		mask |= BIT(clkg->bit_idx + 1);
> +		val |= BIT(clkg->bit_idx + 1);
> +	}
> +
> +	return regmap_update_bits(clkg->clkr.regmap, clkg->gate_ofs, mask, val);
> +}
> +
> +static void rtk_clk_regmap_gate_disable(struct clk_hw *hw)
> +{
> +	struct rtk_clk_regmap_gate *clkg = to_rtk_clk_regmap_gate(hw);
> +	unsigned int mask;
> +	unsigned int val;
> +
> +	mask = BIT(clkg->bit_idx);
> +	val = 0;
> +
> +	if (clkg->write_en) {
> +		mask |= BIT(clkg->bit_idx + 1);
> +		val |= BIT(clkg->bit_idx + 1);
> +	}

Could add a comment explaining this write_en thing ? Some kind of volatile bit to commit the change ?

> +
> +	regmap_update_bits(clkg->clkr.regmap, clkg->gate_ofs, mask, val);

Nitpick: the 2 functions above more less copy/paste. 

> +}
> +
> +static int rtk_clk_regmap_gate_is_enabled(struct clk_hw *hw)
> +{
> +	struct rtk_clk_regmap_gate *clkg = to_rtk_clk_regmap_gate(hw);
> +	int ret;
> +	u32 val;
> +
> +	ret = regmap_read(clkg->clkr.regmap, clkg->gate_ofs, &val);
> +	if (ret < 0)
> +		return ret;
> +
> +	return !!(val & BIT(clkg->bit_idx));
> +}
> +
> +const struct clk_ops rtk_clk_regmap_gate_ops = {
> +	.enable     = rtk_clk_regmap_gate_enable,
> +	.disable    = rtk_clk_regmap_gate_disable,
> +	.is_enabled = rtk_clk_regmap_gate_is_enabled,
> +};
> +EXPORT_SYMBOL_NS_GPL(rtk_clk_regmap_gate_ops, "CLK_REALTEK");
> +
> +const struct clk_ops rtk_clk_regmap_gate_ro_ops = {
> +	.is_enabled = rtk_clk_regmap_gate_is_enabled,
> +};
> +EXPORT_SYMBOL_NS_GPL(rtk_clk_regmap_gate_ro_ops, "CLK_REALTEK");
> diff --git a/drivers/clk/realtek/clk-regmap-gate.h b/drivers/clk/realtek/clk-regmap-gate.h
> new file mode 100644
> index 000000000000..9303adda3166
> --- /dev/null
> +++ b/drivers/clk/realtek/clk-regmap-gate.h
> @@ -0,0 +1,65 @@
> +/* SPDX-License-Identifier: GPL-2.0-only */
> +/*
> + * Copyright (C) 2017-2026 Realtek Semiconductor Corporation
> + * Author: Cheng-Yu Lee <cylee12@realtek.com>
> + */
> +
> +#ifndef __CLK_REALTEK_CLK_REGMAP_GATE_H
> +#define __CLK_REALTEK_CLK_REGMAP_GATE_H
> +
> +#include "clk-rtk-common.h"
> +
> +struct rtk_clk_regmap_gate {
> +	struct rtk_clk_regmap clkr;
> +	unsigned int gate_ofs;
> +	u8 bit_idx;
> +	u32 write_en : 1;
> +};
> +
> +#define __rtk_clk_regmap_gate_hw(_p) __rtk_clk_regmap_hw(&(_p)->clkr)
> +
> +#define __RTK_CLK_REGMAP_GATE(_name, _parent, _ops, _flags, _ofs, _bit_idx, \
> +			      _write_en)                                    \
> +	struct rtk_clk_regmap_gate _name = {                                \
> +		.clkr.hw.init = CLK_HW_INIT(#_name, _parent, _ops, _flags), \
> +		.gate_ofs = _ofs,                                           \
> +		.bit_idx = _bit_idx,                                        \
> +		.write_en = _write_en,                                      \
> +	}
> +
> +#define RTK_CLK_REGMAP_GATE(_name, _parent, _flags, _ofs, _bit_idx, _write_en)        \
> +	__RTK_CLK_REGMAP_GATE(_name, _parent, &rtk_clk_regmap_gate_ops, _flags, _ofs, \
> +			      _bit_idx, _write_en)
> +
> +#define RTK_CLK_REGMAP_GATE_RO(_name, _parent, _flags, _ofs, _bit_idx, _write_en)  \
> +	__RTK_CLK_REGMAP_GATE(_name, _parent, &rtk_clk_regmap_gate_ro_ops, _flags, \
> +			  _ofs, _bit_idx, _write_en)
> +
> +#define __RTK_CLK_REGMAP_GATE_NO_PARENT(_name, _ops, _flags, _ofs, _bit_idx,  \
> +				    _write_en)                                \
> +	struct rtk_clk_regmap_gate _name = {                                  \
> +		.clkr.hw.init = CLK_HW_INIT_NO_PARENT(#_name, _ops, _flags),  \
> +		.gate_ofs = _ofs,                                             \
> +		.bit_idx = _bit_idx,                                          \
> +		.write_en = _write_en,                                        \
> +	}
> +
> +#define RTK_CLK_REGMAP_GATE_NO_PARENT(_name, _flags, _ofs, _bit_idx, _write_en)        \
> +	__RTK_CLK_REGMAP_GATE_NO_PARENT(_name, &rtk_clk_regmap_gate_ops, _flags, _ofs, \
> +				    _bit_idx, _write_en)
> +
> +#define RTK_CLK_REGMAP_GATE_NO_PARENT_RO(_name, _flags, _ofs, _bit_idx, _write_en)  \
> +	__RTK_CLK_REGMAP_GATE_NO_PARENT(_name, &rtk_clk_regmap_gate_ro_ops, _flags, \
> +				    _ofs, _bit_idx, _write_en)
> +
> +static inline struct rtk_clk_regmap_gate *to_rtk_clk_regmap_gate(struct clk_hw *hw)
> +{
> +	struct rtk_clk_regmap *clkr = to_rtk_clk_regmap(hw);
> +
> +	return container_of(clkr, struct rtk_clk_regmap_gate, clkr);
> +}
> +
> +extern const struct clk_ops rtk_clk_regmap_gate_ops;
> +extern const struct clk_ops rtk_clk_regmap_gate_ro_ops;
> +
> +#endif /* __CLK_REALTEK_CLK_REGMAP_GATE_H */
> -- 
> 2.43.0
> 
>