RE: [PATCH v6 03/10] clk: realtek: Introduce a common probe()

["Yu-Chun Lin [林祐君]" <eleanor.lin@realtek.com>]

Hi Brian,

> Hi Cheng-Yu,
> 
> On Thu, Apr 02, 2026 at 03:39:50PM +0800, Cheng-Yu Lee wrote:
> > Add rtk_clk_probe() to set up the shared regmap, register clock
> > hardware, and add the clock provider.
> >
> > Additionally, if the "#reset-cells" property is present in the device
> > tree, it creates and registers an auxiliary device using the provided
> aux_name.
> > This allows the dedicated reset driver to bind to this device,
> > enabling both clock and reset drivers to share the same regmap.
> >
> > 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>
> > ---
> > Changes in v6:
> > - Replace direct reset controller initialization with auxiliary device creation.
> > - Add aux_name parameter to rtk_clk_probe() to register the reset auxiliary
> device.
> > - Simplify rtk_clk_desc because reset data is handled entirely by the auxiliary
> reset driver.
> > - In Kconfig, change "depends on RESET_CONTROLLER" to "select
> RESET_CONTROLLER"
> > - Remove unused includes headers and added <linux/auxiliary_bus.h>.
> > ---
> >  MAINTAINERS                  |  1 +
> >  drivers/clk/Kconfig          |  1 +
> >  drivers/clk/Makefile         |  1 +
> >  drivers/clk/realtek/Kconfig  | 28 +++++++++++++++
> > drivers/clk/realtek/Makefile |  4 +++  drivers/clk/realtek/common.c |
> > 67 ++++++++++++++++++++++++++++++++++++
> >  drivers/clk/realtek/common.h | 37 ++++++++++++++++++++
> >  7 files changed, 139 insertions(+)
> >  create mode 100644 drivers/clk/realtek/Kconfig  create mode 100644
> > drivers/clk/realtek/Makefile  create mode 100644
> > drivers/clk/realtek/common.c  create mode 100644
> > drivers/clk/realtek/common.h
> >
> > diff --git a/MAINTAINERS b/MAINTAINERS index
> > 8f355896583b..8318156a02b5 100644
> > --- a/MAINTAINERS
> > +++ b/MAINTAINERS
> > @@ -22240,6 +22240,7 @@ L:    devicetree@vger.kernel.org
> >  L:   linux-clk@vger.kernel.org
> >  S:   Supported
> >  F:   Documentation/devicetree/bindings/clock/realtek*
> > +F:   drivers/clk/realtek/*
> >  F:   drivers/reset/realtek/*
> >  F:   include/dt-bindings/clock/realtek*
> >  F:   include/dt-bindings/reset/realtek*
> > diff --git a/drivers/clk/Kconfig b/drivers/clk/Kconfig index
> > 3d803b4cf5c1..d60f6415b0a3 100644
> > --- a/drivers/clk/Kconfig
> > +++ b/drivers/clk/Kconfig
> > @@ -519,6 +519,7 @@ source "drivers/clk/nuvoton/Kconfig"
> >  source "drivers/clk/pistachio/Kconfig"
> >  source "drivers/clk/qcom/Kconfig"
> >  source "drivers/clk/ralink/Kconfig"
> > +source "drivers/clk/realtek/Kconfig"
> >  source "drivers/clk/renesas/Kconfig"
> >  source "drivers/clk/rockchip/Kconfig"
> >  source "drivers/clk/samsung/Kconfig"
> > diff --git a/drivers/clk/Makefile b/drivers/clk/Makefile index
> > f7bce3951a30..69b84d1e7bcc 100644
> > --- a/drivers/clk/Makefile
> > +++ b/drivers/clk/Makefile
> > @@ -140,6 +140,7 @@ obj-$(CONFIG_COMMON_CLK_PISTACHIO)
> += pistachio/
> >  obj-$(CONFIG_COMMON_CLK_PXA)         += pxa/
> >  obj-$(CONFIG_COMMON_CLK_QCOM)                += qcom/
> >  obj-y                                        += ralink/
> > +obj-$(CONFIG_COMMON_CLK_REALTEK)     += realtek/
> >  obj-y                                        += renesas/
> >  obj-$(CONFIG_ARCH_ROCKCHIP)          += rockchip/
> >  obj-$(CONFIG_COMMON_CLK_SAMSUNG)     += samsung/
> > diff --git a/drivers/clk/realtek/Kconfig b/drivers/clk/realtek/Kconfig
> > new file mode 100644 index 000000000000..bc47d3f1c452
> > --- /dev/null
> > +++ b/drivers/clk/realtek/Kconfig
> > @@ -0,0 +1,28 @@
> > +# SPDX-License-Identifier: GPL-2.0-only config COMMON_CLK_REALTEK
> > +     bool "Clock driver for Realtek SoCs"
> > +     depends on ARCH_REALTEK || COMPILE_TEST
> > +     default ARCH_REALTEK
> > +     help
> > +       Enable the common clock framework infrastructure for Realtek
> > +       system-on-chip platforms.
> > +
> > +       This provides the base support required by individual Realtek
> > +       clock controller drivers to expose clocks to peripheral devices.
> > +
> > +       If you have a Realtek-based platform, say Y.
> > +
> > +if COMMON_CLK_REALTEK
> > +
> > +config RTK_CLK_COMMON
> > +     tristate "Realtek Clock Common"
> > +     select RESET_CONTROLLER
> > +     select RESET_RTK_COMMON
> 
> select AUXILIARY_BUS ?
>

Ack.

> > +     help
> > +       Common helper code shared by Realtek clock controller drivers.
> > +
> > +       This provides utility functions and data structures used by
> > +       multiple Realtek clock implementations, and include integration
> > +       with reset controllers where required.
> > +
> > +endif
> > diff --git a/drivers/clk/realtek/Makefile
> > b/drivers/clk/realtek/Makefile new file mode 100644 index
> > 000000000000..377ec776ee47
> > --- /dev/null
> > +++ b/drivers/clk/realtek/Makefile
> > @@ -0,0 +1,4 @@
> > +# SPDX-License-Identifier: GPL-2.0-only
> > +obj-$(CONFIG_RTK_CLK_COMMON) += clk-rtk.o
> > +
> > +clk-rtk-y += common.o
> > diff --git a/drivers/clk/realtek/common.c
> > b/drivers/clk/realtek/common.c new file mode 100644 index
> > 000000000000..c5aea15a3714
> > --- /dev/null
> > +++ b/drivers/clk/realtek/common.c
> > @@ -0,0 +1,67 @@
> > +// SPDX-License-Identifier: GPL-2.0-only
> > +/*
> > + * Copyright (C) 2019 Realtek Semiconductor Corporation
> 
> If you are making changes here, should the copyrights be updated to include
> 2026?
> 

Agreed. Will include 2026.

> > + * Author: Cheng-Yu Lee <cylee12@realtek.com> */
> > +
> > +#include <linux/auxiliary_bus.h>
> > +#include <linux/device.h>
> > +#include <linux/mfd/syscon.h>
> > +#include <linux/module.h>
> > +#include <linux/platform_device.h>
> > +#include "common.h"
> > +
> > +static int rtk_reset_controller_register(struct device *dev, const
> > +char *aux_name) {
> > +     struct auxiliary_device *adev;
> > +
> > +     if (!of_property_present(dev->of_node, "#reset-cells"))
> > +             return 0;
> > +
> > +     adev = devm_auxiliary_device_create(dev, aux_name, NULL);
> > +
> > +     if (IS_ERR(adev))
> > +             return PTR_ERR(adev);
> > +     return 0;
> 
> Add newline before return.
> 

Ack.

> > +}
> > +
> > +int rtk_clk_probe(struct platform_device *pdev, const struct rtk_clk_desc
> *desc,
> > +               const char *aux_name)
> > +{
> > +     int i, ret;
> > +     struct regmap *regmap;
> > +     struct device *dev = &pdev->dev;
> 
> Put variables in reverse Christmas tree order.
> 

Ack.

> > +
> > +     regmap = device_node_to_regmap(pdev->dev.of_node);
> > +     if (IS_ERR(regmap))
> > +             return dev_err_probe(dev, PTR_ERR(regmap), "failed to
> > + get regmap\n");
> > +
> > +     for (i = 0; i < desc->num_clks; i++)
> > +             desc->clks[i]->regmap = regmap;
> > +
> > +     for (i = 0; i < desc->clk_data->num; i++) {
> > +             struct clk_hw *hw = desc->clk_data->hws[i];
> > +
> > +             if (!hw)
> > +                     continue;
> > +
> > +             ret = devm_clk_hw_register(dev, hw);
> > +
> > +             if (ret) {
> 
> Remove newline before if.
>

Ack.

> > +                     dev_warn(dev, "failed to register hw of clk%d:
> %d\n", i,
> > +                              ret);
> > +                     desc->clk_data->hws[i] = NULL;
> 
> This chunk doesn't take into account probe deferrals.

Will return error here.

Best Regards,
Yu-Chun

> 
> Brian