Re: [PATCH v5 2/2] phy: qcom-mipi-csi2: Add a CSI2 MIPI DPHY driver

[Hangxiang Ma <hangxiang.ma@oss.qualcomm.com>]

On 3/26/2026 9:04 AM, Bryan O'Donoghue wrote:
> +#include <linux/delay.h>
> +#include <linux/interrupt.h>
> +#include <linux/io.h>
> +#include <linux/time64.h>
> +
> +#include "phy-qcom-mipi-csi2.h"
> +
> +#define CSIPHY_3PH_CMN_CSI_COMMON_CTRLn(offset, n)	((offset) + 0x4 * (n))
> +#define CSIPHY_3PH_CMN_CSI_COMMON_CTRL0_PHY_SW_RESET	BIT(0)
> +#define CSIPHY_3PH_CMN_CSI_COMMON_CTRL5_CLK_ENABLE	BIT(7)
> +#define CSIPHY_3PH_CMN_CSI_COMMON_CTRL6_COMMON_PWRDN_B	BIT(0)
> +#define CSIPHY_3PH_CMN_CSI_COMMON_CTRL6_SHOW_REV_ID	BIT(1)
> +#define CSIPHY_3PH_CMN_CSI_COMMON_CTRL10_IRQ_CLEAR_CMD	BIT(0)
> +#define CSIPHY_3PH_CMN_CSI_COMMON_STATUSn(offset, n)	((offset) + 0xb0 + 0x4 * (n))
>
Hi Bryan, one minor observation on the following macro:

	CSIPHY_3PH_CMN_CSI_COMMON_STATUSn

The 0xb0 offset implicitly assumes a fixed distance between the
common_ctrl and common_status register blocks. This holds for the PHYs
covered by this series, but on some other platforms (e.g. Kaanapali,
Pakala) the offset differs.

That said, I think keeping this fixed value is reasonable for the scope
of the current PHY series, and it does help keep the macro set simple.
It might just be worth documenting this assumption (e.g. via a comment
or in the commit message).

Alternatively, if future PHY variants need to support different layouts,
this could be made more extensible by moving the status base offset into
the per-PHY data (similar to other register layout parameters). But I
don’t think that needs to block the current series.

Related patch before:
<https://lore.kernel.org/all/20260112-camss-extended-csiphy-macro-v2-1-ee7342f2aaf5@oss.qualcomm.com/>

Best Regards,
Hangxiang