Hi Daniel,
On Di, 2025-02-18 at 10:57 +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.
>
> Signed-off-by: Daniel Baluta <daniel.baluta@xxxxxxx>
> ---
> 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
Will any of the reset controls manipulate multiple bits at once?
I'd use BIT(0) and BIT(1) here.
> +
> +#define IMX8MP_AUDIOMIX_EARC 0
> +#define IMX8MP_AUDIOMIX_EARC_PHY 1
> +
> +#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] = {
If you make this reset_map[], drop IMX8MP_AUDIOMIX_RESET_NUM, and use
.nr_resets = ARRAY_SIZE(reset_map) below, followup patches that add new
bits will be simplified.
> + [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,
> + },
> +
Please drop this empty line.
> +};
>
> 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)
Whitespace error. But also, this check is not necessary.
The reset core will not return reset controls that fail the same check
in of_reset_simple_xlate(), so we can never get here with the wrong id
if rcdev.nr_resets correctly is set to ARRAY_SIZE(reset_map).
> + 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;
Same as above.
> +
> + 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;
Could use ARRAY_SIZE(reset_map) here.
regards
Philipp
