Re: Re: [PATCH v4 2/3] clk: eswin: Add eic7700 HSP clock driver

From: Xuyang Dong

Date: Wed May 13 2026 - 22:30:47 EST


>
> On Tue, May 12, 2026 at 10:07:47AM +0800, Xuyang Dong wrote:
> > Add driver for the ESWIN EIC7700 high-speed peripherals system
> > clock controller and register an auxiliary device for system
> > reset controller which is named as "hsp-reset".
> >
> > Signed-off-by: Xuyang Dong <dongxuyang@xxxxxxxxxxxxxxxxxx>
> > ---
> > drivers/clk/eswin/Kconfig | 12 +
> > drivers/clk/eswin/Makefile | 1 +
> > drivers/clk/eswin/clk-eic7700-hsp.c | 338 ++++++++++++++++++++++++++++
> > 3 files changed, 351 insertions(+)
> > create mode 100644 drivers/clk/eswin/clk-eic7700-hsp.c
> >
> > diff --git a/drivers/clk/eswin/Kconfig b/drivers/clk/eswin/Kconfig
> > index 0406ec499ec9..e6cc2a407bac 100644
> > --- a/drivers/clk/eswin/Kconfig
> > +++ b/drivers/clk/eswin/Kconfig
> > @@ -13,3 +13,15 @@ config COMMON_CLK_EIC7700
> > SoC. The clock controller generates and supplies clocks to various
> > peripherals within the SoC.
> > Say yes here to support the clock controller on the EIC7700 SoC.
> > +
> > +config COMMON_CLK_EIC7700_HSP
> > + tristate "EIC7700 HSP Clock Driver"
> > + depends on ARCH_ESWIN || COMPILE_TEST
> > + select AUXILIARY_BUS
> > + select COMMON_CLK_EIC7700
> > + select RESET_EIC7700_HSP if RESET_CONTROLLER
> > + help
> > + This driver provides support for clock controller on ESWIN EIC7700
> > + HSP. The clock controller generates and supplies clocks to high
> > + speed peripherals within the SoC.
> > + Say yes here to support the clock controller on the EIC7700 HSP.
> > diff --git a/drivers/clk/eswin/Makefile b/drivers/clk/eswin/Makefile
> > index 4a7c2af82164..21a09a3396df 100644
> > --- a/drivers/clk/eswin/Makefile
> > +++ b/drivers/clk/eswin/Makefile
> > @@ -6,3 +6,4 @@
> > obj-$(CONFIG_COMMON_CLK_ESWIN) += clk.o
> >
> > obj-$(CONFIG_COMMON_CLK_EIC7700) += clk-eic7700.o
> > +obj-$(CONFIG_COMMON_CLK_EIC7700_HSP) += clk-eic7700-hsp.o
> > diff --git a/drivers/clk/eswin/clk-eic7700-hsp.c b/drivers/clk/eswin/clk-eic7700-hsp.c
> > new file mode 100644
> > index 000000000000..0d5bd5b705dc
> > --- /dev/null
> > +++ b/drivers/clk/eswin/clk-eic7700-hsp.c
> > @@ -0,0 +1,338 @@
> > +// SPDX-License-Identifier: GPL-2.0
> > +/*
> > + * Copyright 2026, Beijing ESWIN Computing Technology Co., Ltd..
> > + * All rights reserved.
> > + *
> > + * ESWIN EIC7700 HSP Clock Driver
> > + *
> > + * Authors: Xuyang Dong <dongxuyang@xxxxxxxxxxxxxxxxxx>
> > + */
> > +
> > +#include <linux/auxiliary_bus.h>
> > +#include <linux/clk-provider.h>
> > +#include <linux/platform_device.h>
> > +#include <linux/regmap.h>
> > +
> > +#include <dt-bindings/clock/eswin,eic7700-hspcrg.h>
> > +
> > +#include "common.h"
> > +
> > +#define EIC7700_HSP_SATA_REG 0x300
> > +#define EIC7700_HSP_MSHC0_REG 0x510
> > +#define EIC7700_HSP_MSHC1_REG 0x610
> > +#define EIC7700_HSP_MSHC2_REG 0x710
> > +#define EIC7700_HSP_USB0_REG 0x800
> > +#define EIC7700_HSP_USB0_REF_REG 0x83c
> > +#define EIC7700_HSP_USB1_REG 0x900
> > +#define EIC7700_HSP_USB1_REF_REG 0x93c
> > +
> > +#define USB_REF_XTAL24M 0x2a
> > +#define EIC7700_HSP_NR_CLKS (EIC7700_HSP_CLK_GATE_SATA + 1)
> > +
> > +struct eic7700_hsp_clk_gate {
> > + struct clk_hw hw;
> > + unsigned int id;
> > + struct regmap *regmap;
> > + unsigned int reg;
> > + unsigned int ref_reg;
> > + const char *name;
> > + const struct clk_parent_data *parent_data;
> > + unsigned long flags;
> > + unsigned int offset;
> > + unsigned int ref_offset;
> > + u8 bit_idx;
> > +};
> > +
> > +static const struct regmap_config eic7700_hsp_regmap_config = {
> > + .reg_bits = 32,
> > + .val_bits = 32,
> > + .max_register = 0x1ffc,
> > + .reg_stride = 4,
> > + .fast_io = true,
> > + .use_raw_spinlock = true,
> > +};
> > +
> > +static inline struct eic7700_hsp_clk_gate *to_gate_clk(struct clk_hw *hw)
> > +{
> > + return container_of(hw, struct eic7700_hsp_clk_gate, hw);
> > +}
> > +
> > +#define EIC7700_HSP_GATE(_id, _name, _pdata, _flags, _offset, _idx, \
> > + _ref_offset) \
> > + { \
> > + .id = _id, \
> > + .name = _name, \
> > + .parent_data = _pdata, \
> > + .flags = _flags, \
> > + .offset = _offset, \
> > + .ref_offset = _ref_offset, \
> > + .bit_idx = _idx, \
> > + }
> > +
> > +static void hsp_clk_gate_endisable(struct clk_hw *hw, bool enable)
> > +{
> > + struct eic7700_hsp_clk_gate *gate = to_gate_clk(hw);
> > +
> > + if (enable) {
> > + /*
> > + * Hardware bug: The USB reference clock must be 24MHz.
> > + * The default register value after reset is invalid.
> > + * Workaround: Rewrite the correct value before enabling
> > + * the USB gate clock.
> > + */
> > + regmap_update_bits(gate->regmap, gate->ref_reg, 0x3f,
> > + USB_REF_XTAL24M);
> > + }
> > + regmap_assign_bits(gate->regmap, gate->reg, BIT(gate->bit_idx), enable);
> > +}
> > +
> > +static int hsp_clk_gate_enable(struct clk_hw *hw)
> > +{
> > + hsp_clk_gate_endisable(hw, true);
> > +
> > + return 0;
> > +}
> > +
> > +static void hsp_clk_gate_disable(struct clk_hw *hw)
> > +{
> > + hsp_clk_gate_endisable(hw, false);
> > +}
> > +
> > +static int hsp_clk_gate_is_enabled(struct clk_hw *hw)
> > +{
> > + struct eic7700_hsp_clk_gate *gate = to_gate_clk(hw);
> > + unsigned int val;
> > +
> > + regmap_read(gate->regmap, gate->reg, &val);
> > +
> > + return !!(val & BIT(gate->bit_idx));
>
> If the regmap_read() fails, then val will be uninitialized.

Hi Brian and Sashiko,

I will update the following code to address this in next version.

+ int ret;
+
+ ret = regmap_read(gate->regmap, gate->reg, &val);
+ if (ret != 0)
+ return ret;

Does this change look acceptable to you?

Best regards,
Xuyang Dong

>
> With that fixed:
>
> Reviewed-by: Brian Masney <bmasney@xxxxxxxxxx>