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Commit8006aff155("crypto: atmel-sha204a - Set hwrng quality to lowest possible") reduced the hwrng quality to 1 based on a review by Bill Cox [1]. However, despite its title, the review only tested the ATSHA204, not the ATSHA204A. In the same thread, Atmel engineer Landon Cox wrote "this behavior has been eliminated entirely"[2] in the ATSHA204A and "this problem does not affect the ATECC108 or the ATECC108A (or the ATSHA204A)"[3]. According to the official ATSHA204A datasheet [4], the device contains a high-quality hardware RNG that combines its output with an internal seed value stored in EEPROM or SRAM to generate random numbers. The device also implements all security functions using SHA-256, and the driver uses the chip's Random command in seed-update mode. Keep 'quality = 1' for ATSHA204, but drop the explicit hwrng quality reduction for ATSHA204A and fall back to the hwrng core default. [1] https://www.metzdowd.com/pipermail/cryptography/2014-December/023858.html [2] https://www.metzdowd.com/pipermail/cryptography/2014-December/023852.html [3] https://www.metzdowd.com/pipermail/cryptography/2014-December/023886.html [4] https://ww1.microchip.com/downloads/en/DeviceDoc/ATSHA204A-Data-Sheet-40002025A.pdf Fixes:8006aff155("crypto: atmel-sha204a - Set hwrng quality to lowest possible") Cc: stable@vger.kernel.org Signed-off-by: Thorsten Blum <thorsten.blum@linux.dev> Reviewed-by: Ard Biesheuvel <ardb@kernel.org> Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>