Re: [PATCH 2/5] reset: imx8mp-audiomix: Prepare the code for more reset bits

[Frank Li <Frank.li@nxp.com>]

On Tue, Feb 18, 2025 at 10:57:09AM +0200, Daniel Baluta wrote:
> Current code supports EARC PHY Software Reset and EARC 	Software
> Reset but it is not easily extensible to more reset bits.
>
> So, refactor the code in order to easily allow more reset bits
> in the future.

Nit: wrap at 75 chars

>
> Signed-off-by: Daniel Baluta <daniel.baluta@nxp.com>
> ---
>  drivers/reset/reset-imx8mp-audiomix.c | 53 ++++++++++++++++++++++-----
>  1 file changed, 43 insertions(+), 10 deletions(-)
>
> diff --git a/drivers/reset/reset-imx8mp-audiomix.c b/drivers/reset/reset-imx8mp-audiomix.c
> index 1fe21980a66c..6b1666c4e069 100644
> --- a/drivers/reset/reset-imx8mp-audiomix.c
> +++ b/drivers/reset/reset-imx8mp-audiomix.c
> @@ -12,7 +12,30 @@
>  #include <linux/reset-controller.h>
>
>  #define IMX8MP_AUDIOMIX_EARC_OFFSET		0x200
> -#define IMX8MP_AUDIOMIX_EARC_RESET_MASK		0x3
> +#define IMX8MP_AUDIOMIX_EARC_RESET_MASK		0x1
> +#define IMX8MP_AUDIOMIX_EARC_PHY_RESET_MASK	0x2
> +
> +#define IMX8MP_AUDIOMIX_EARC		0
> +#define IMX8MP_AUDIOMIX_EARC_PHY	1


Does dt binding need such macro?

If not, you can use enum.
If yes, create binding header file for it.

Frank
> +
> +#define IMX8MP_AUDIOMIX_RESET_NUM	2
> +
> +struct imx8mp_reset_map {
> +	unsigned int offset;
> +	unsigned int mask;
> +};
> +
> +static const struct imx8mp_reset_map reset_map[IMX8MP_AUDIOMIX_RESET_NUM] = {
> +	[IMX8MP_AUDIOMIX_EARC] = {
> +		.offset	= IMX8MP_AUDIOMIX_EARC_OFFSET,
> +		.mask	= IMX8MP_AUDIOMIX_EARC_RESET_MASK,
> +	},
> +	[IMX8MP_AUDIOMIX_EARC_PHY] = {
> +		.offset	= IMX8MP_AUDIOMIX_EARC_OFFSET,
> +		.mask	= IMX8MP_AUDIOMIX_EARC_PHY_RESET_MASK,
> +	},
> +
> +};
>
>  struct imx8mp_audiomix_reset {
>  	struct reset_controller_dev rcdev;
> @@ -30,13 +53,18 @@ static int imx8mp_audiomix_reset_assert(struct reset_controller_dev *rcdev,
>  {
>  	struct imx8mp_audiomix_reset *priv = to_imx8mp_audiomix_reset(rcdev);
>  	void __iomem *reg_addr = priv->base;
> -	unsigned int mask, reg;
> +	unsigned int mask, offset, reg;
>  	unsigned long flags;
>
> -	mask = BIT(id);
> +	if (id >=  IMX8MP_AUDIOMIX_RESET_NUM)
> +		return -EINVAL;
> +
> +	mask = reset_map[id].mask;
> +	offset = reset_map[id].offset;
> +
>  	spin_lock_irqsave(&priv->lock, flags);
> -	reg = readl(reg_addr + IMX8MP_AUDIOMIX_EARC_OFFSET);
> -	writel(reg & ~mask, reg_addr + IMX8MP_AUDIOMIX_EARC_OFFSET);
> +	reg = readl(reg_addr + offset);
> +	writel(reg & ~mask, reg_addr + offset);
>  	spin_unlock_irqrestore(&priv->lock, flags);
>
>  	return 0;
> @@ -47,13 +75,18 @@ static int imx8mp_audiomix_reset_deassert(struct reset_controller_dev *rcdev,
>  {
>  	struct imx8mp_audiomix_reset *priv = to_imx8mp_audiomix_reset(rcdev);
>  	void __iomem *reg_addr = priv->base;
> -	unsigned int mask, reg;
> +	unsigned int mask, offset, reg;
>  	unsigned long flags;
>
> -	mask = BIT(id);
> +	if (id >=  IMX8MP_AUDIOMIX_RESET_NUM)
> +		return -EINVAL;
> +
> +	mask = reset_map[id].mask;
> +	offset = reset_map[id].offset;
> +
>  	spin_lock_irqsave(&priv->lock, flags);
> -	reg = readl(reg_addr + IMX8MP_AUDIOMIX_EARC_OFFSET);
> -	writel(reg | mask, reg_addr + IMX8MP_AUDIOMIX_EARC_OFFSET);
> +	reg = readl(reg_addr + offset);
> +	writel(reg | mask, reg_addr + offset);
>  	spin_unlock_irqrestore(&priv->lock, flags);
>
>  	return 0;
> @@ -78,7 +111,7 @@ static int imx8mp_audiomix_reset_probe(struct auxiliary_device *adev,
>  	spin_lock_init(&priv->lock);
>
>  	priv->rcdev.owner     = THIS_MODULE;
> -	priv->rcdev.nr_resets = fls(IMX8MP_AUDIOMIX_EARC_RESET_MASK);
> +	priv->rcdev.nr_resets = IMX8MP_AUDIOMIX_RESET_NUM;
>  	priv->rcdev.ops       = &imx8mp_audiomix_reset_ops;
>  	priv->rcdev.of_node   = dev->parent->of_node;
>  	priv->rcdev.dev	      = dev;
> --
> 2.25.1
>