sensor: fix IMX335 misdetected as IMX347 after WDR cycle (#157)#167
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0x3057 is Y_OUT_SIZE[12:0] MSB (host-writable, V-reflection), not a chip ID — Sony image sensors have no dedicated chip ID register. After majestic configures IMX335 for WDR with vertical cropping, Y_OUT_SIZE drops to ~0x0604 and 0x3057 reads 0x06, colliding with IMX347's reset default, so detect_sony_sensor commits to IMX347 and majestic fails with "No matches for 'imx347_i2c'". Cross-check with OB cropping registers 0x3072 (AREA2_WIDTH_1 LSB) and 0x3074 (AREA3_ST_ADR_1 LSB), which have distinct datasheet defaults (IMX335: 0x28/0xB0, IMX347: 0x14/0x3C) and survive majestic init. When they match the IMX335 fingerprint, fall through to the existing 0x316A IMX335 path instead of committing to IMX347. The originally proposed (0x316A & 0xFC) == 0x7C check alone is not a discriminator: IMX347's datasheet (p.40) shows the same fixed bits as IMX335 — it's an INCKSEL4 shape, not a chip identifier. Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>
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Summary
0x3057isY_OUT_SIZE[12:0]MSB (host-writable per both datasheets), not a chip ID — Sony sensors have no dedicated chip ID register. WDR vertical cropping on IMX335 reprograms Y_OUT_SIZE so the MSB reads0x06, colliding with IMX347's reset default, and the unconditional0x3057 == 0x06 → IMX347short-circuit misdetects.0x3072=0x28, 0x3074=0xB0; IMX347 reads0x3072=0x14, 0x3074=0x3C. When the IMX335 fingerprint matches, fall through to the existing0x316AIMX335 path.(0x316A & 0xFC) == 0x7Ccross-check: IMX347 datasheet p.40 shows the same fixed bits as IMX335, so that check alone is not a discriminator — it's an INCKSEL4 shape, not a chip identifier.Test plan
imx347_i2c, this PR reportsimx335_i2cfrom the same registers, same boot.killall majestic(sensor retains register state without a power-cycle); behaviour is consistent.0x3072 == 0x28 && 0x3074 == 0xB0(IMX335 factory OB defaults); a real IMX347 reading those exact values would have to be deliberately programmed that way, and no published profile does, so false-positive risk is low — but a confirmation from anyone with the part would be welcome.🤖 Generated with Claude Code