Re: [RFC PATCH v2 1/5] clk: meson: axg: move reset controller's code to separate module

From: Stephen Boyd
Date: Tue Apr 09 2024 - 22:27:46 EST


Quoting Conor Dooley (2024-04-09 05:05:37)
> On Mon, Apr 08, 2024 at 06:05:51PM +0100, Conor Dooley wrote:
>
> > > > Seconded, the clk-mpfs/reset-mpfs and clk-starfive-jh7110-sys/reset-
> > > > starfive-jh7110 drivers are examples of this.
> > > >
> > > > > The auxiliary device creation function can also be in the
> > > > > drivers/reset/ directory so that the clk driver calls some function
> > > > > to create and register the device.
> > > >
> > > > I'm undecided about this, do you think mpfs_reset_controller_register()
> > > > and jh7110_reset_controller_register() should rather live with the
> > > > reset aux drivers in drivers/reset/ ?
> > >
> > > Yes, and also mpfs_reset_read() and friends. We should pass the base
> > > iomem pointer and parent device to mpfs_reset_adev_alloc() instead and
> > > then move all that code into drivers/reset with some header file
> > > exported function to call. That way the clk driver hands over the data
> > > without having to implement half the implementation.
> >
> > I'll todo list that :)
>
> Something like the below?
>
> -- >8 --
> From a12f281d2cb869bcd9a6ffc45d0c6a0d3aa2e9e2 Mon Sep 17 00:00:00 2001
> From: Conor Dooley <conor.dooley@xxxxxxxxxxxxx>
> Date: Tue, 9 Apr 2024 11:54:34 +0100
> Subject: [PATCH] clock, reset: microchip: move all mpfs reset code to the
> reset subsystem
>
> <insert something here>
>
> Signed-off-by: Conor Dooley <conor.dooley@xxxxxxxxxxxxx>

Looks pretty good.

> static const struct of_device_id mpfs_clk_of_match_table[] = {
> diff --git a/drivers/reset/reset-mpfs.c b/drivers/reset/reset-mpfs.c
> index 7f3fb2d472f4..27cd68b4ee81 100644
> --- a/drivers/reset/reset-mpfs.c
> +++ b/drivers/reset/reset-mpfs.c
> @@ -137,9 +139,67 @@ static int mpfs_reset_probe(struct auxiliary_device *adev,
> return devm_reset_controller_register(dev, rcdev);
> }
>
> +static void mpfs_reset_unregister_adev(void *_adev)
> +{
> + struct auxiliary_device *adev = _adev;
> +
> + auxiliary_device_delete(adev);
> + auxiliary_device_uninit(adev);
> +}
> +
> +static void mpfs_reset_adev_release(struct device *dev)
> +{
> + struct auxiliary_device *adev = to_auxiliary_dev(dev);
> +
> + kfree(adev);
> +}
> +
> +static struct auxiliary_device *mpfs_reset_adev_alloc(struct device *clk_dev)
> +{
> + struct auxiliary_device *adev;
> + int ret;
> +
> + adev = kzalloc(sizeof(*adev), GFP_KERNEL);
> + if (!adev)
> + return ERR_PTR(-ENOMEM);
> +
> + adev->name = "reset-mpfs";
> + adev->dev.parent = clk_dev;
> + adev->dev.release = mpfs_reset_adev_release;
> + adev->id = 666u;
> +
> + ret = auxiliary_device_init(adev);
> + if (ret) {
> + kfree(adev);
> + return ERR_PTR(ret);
> + }
> +
> + return adev;
> +}
> +
> +int mpfs_reset_controller_register(struct device *clk_dev, void __iomem *base)
> +{
> + struct auxiliary_device *adev;
> + int ret;
> +
> + mpfs_reset_addr = base;

Instead of a global this can be stashed in adev->dev.platform_data and
grabbed in the driver probe?

> +
> + adev = mpfs_reset_adev_alloc(clk_dev);
> + if (IS_ERR(adev))
> + return PTR_ERR(adev);
> +
> + ret = auxiliary_device_add(adev);
> + if (ret) {
> + auxiliary_device_uninit(adev);
> + return ret;
> + }
> +
> + return devm_add_action_or_reset(clk_dev, mpfs_reset_unregister_adev, adev);
> +}
> +
> static const struct auxiliary_device_id mpfs_reset_ids[] = {
> {
> - .name = "clk_mpfs.reset-mpfs",
> + .name = "reset_mpfs.reset-mpfs",
> },
> { }
> };
> diff --git a/include/soc/microchip/mpfs.h b/include/soc/microchip/mpfs.h
> index 09722f83b0ca..0b756bf5e9bd 100644
> --- a/include/soc/microchip/mpfs.h
> +++ b/include/soc/microchip/mpfs.h
> @@ -43,11 +43,11 @@ struct mtd_info *mpfs_sys_controller_get_flash(struct mpfs_sys_controller *mpfs_
> #endif /* if IS_ENABLED(CONFIG_POLARFIRE_SOC_SYS_CTRL) */
>
> #if IS_ENABLED(CONFIG_MCHP_CLK_MPFS)
> -
> -u32 mpfs_reset_read(struct device *dev);
> -
> -void mpfs_reset_write(struct device *dev, u32 val);
> -
> +#if IS_ENABLED(CONFIG_RESET_CONTROLLER)
> +int mpfs_reset_controller_register(struct device *clk_dev, void __iomem *base);
> +#else
> +int mpfs_reset_controller_register(struct device *clk_dev, void* __iomem base) { return 0;}

static inline