Re: [PATCH v15 06/11] clk: realtek: Add support for gate clock

[Jerome Brunet <jbrunet@baylibre.com>]

> Introduce clk_regmap_gate_ops supporting enable, disable, and is_enabled
> for standard regmap gate clocks. To accommodate hardware designs, the
> enable and disable operations handle a 'write_en' flag, which asserts an
> adjacent write-enable bit (bit_idx + 1) simultaneously when modifying the
> gate bit.
> 
> 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>
> Signed-off-by: Yu-Chun Lin <eleanor.lin@realtek.com>
> Reviewed-by: Brian Masney <bmasney@redhat.com>
>
> 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..7033aeb1cd82
> --- /dev/null
> +++ b/drivers/clk/realtek/clk-regmap-gate.c
> @@ -0,0 +1,64 @@
> +// 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_update(struct clk_hw *hw, bool enable)
> +{
> +	struct rtk_clk_regmap_gate *clkg = to_rtk_clk_regmap_gate(hw);
> +	unsigned int mask = BIT(clkg->bit_idx);
> +	unsigned int val = enable ? mask : 0;
> +
> +	/*
> +	 * Hardware specific design: to modify the gate bit, the adjacent
> +	 * write-enable bit (bit_idx + 1) must be asserted simultaneously.
> +	 */
> +	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 int rtk_clk_regmap_gate_enable(struct clk_hw *hw)
> +{
> +	return rtk_clk_regmap_gate_update(hw, true);
> +}
> +
> +static void rtk_clk_regmap_gate_disable(struct clk_hw *hw)
> +{
> +	rtk_clk_regmap_gate_update(hw, false);
> +}
> +
> +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)

Is this _NO_PARENT still used ? if not drop it

-- 
Jerome