Re: [PATCH v8 2/2] phy: qcom-mipi-csi2: Add a CSI2 MIPI DPHY driver

[Bryan O'Donoghue]

On 05/06/2026 10:31, Nihal Kumar Gupta wrote:
> > Having clock-names property doesn't mean that all values are valid.
> CSI_COMMON_CTRL5 is a physical lane power-up bitmap:
> - Bits [0,2,4,6] → D-PHY data lanes(LN0, LN2, LN4, LN6)
> - Bits [1,3,5] → C-PHY trio lanes(LN1, LN3, LN5)
> - Bit [7] → D-PHY clock lane(LNCK) dedicated clock enable
>
> In combo mode, only LN6 can be configurable as a clock lane.
>
> The lane-enable computation in phy_qcom_mipi_csi2_lanes_enable() uses
> BIT(data[i].pos) directly, assuming physical bit positions <0 2 4 6>,
> but the DT [1] uses conventional indices <0 1 2 3>, producing 0x8F
> instead of the correct 0xD5.
>
> This goes unnoticed because the wrong value is immediately overwritten by the
> hardcoded 0xD5 in lane_regs_x1e80100, making the dynamic computation effectively dead.
>
> Could you please fix the driver to map logical lane indices, consistent with the gen2 camss convention.
>
> [1]https://lore.kernel.org/all/20260326-x1e-camss-csi2-phy-dtsi- 
> v3-5-1d5a9306116a@xxxxxxxxxx

That's great, thank you for sharing this information, it moves us from 
"I think" to "the documentation says"

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bod