Hi, This is a follow up of my questions around exynos-rng [1]. Changes since v2: ================= 1. Do not re-use random numbers for re-seed (neither for system resume nor for periodic re-seed). Instead the driver will just generate new random numbers (suggested by Stephan Müller). Suspend path tested with suspend-to-freeze, not real suspend. Testing on Trats2 would be welcomed. Changes since v1: ================= 1. Re-work the code for seeding after system resume, following suggestions and review by Stephan Müller. 2. Re-seed itself from time to time (every 100 ms), suggested by Stephan Müller. 3. Use a define for retries (Bartlomiej Zolnierkiewicz). 4. Add some docs. Description: ============ The existing exynos-rng has many issues. The most important one is that it is a pseudo RNG device but uses hw_random interface which does not allow proper seeding. The RNG module on Exynos4 requires seeding. On newer SoCs (like Exynos5420) it can seed itself from a true RNG. Converting the existing driver to use TRNG would effectively drop support for Exynos4 and break compatibility with existing users. Instead I decided to convert it to crypto API. In the future I hope to add support for seeding from TRNG module. Tested with app [2]. Patches are independent. I will take the defconfig changes (2/3 and 3/3) through samsung-soc tree. Best regards, Krzysztof [1] https://www.spinics.net/lists/arm-kernel/msg569641.html [2] https://www.spinics.net/lists/arm-kernel/msg571184.html Krzysztof Kozlowski (3): crypto: hw_random - Add new Exynos RNG driver ARM: exynos_defconfig: Enable Exynos RNG and user-space crypto API ARM: multi_v7_defconfig: Enable Exynos RNG and user-space crypto API MAINTAINERS | 8 + arch/arm/configs/exynos_defconfig | 6 + arch/arm/configs/multi_v7_defconfig | 6 + drivers/char/hw_random/Kconfig | 14 -- drivers/char/hw_random/Makefile | 1 - drivers/char/hw_random/exynos-rng.c | 231 --------------------- drivers/crypto/Kconfig | 15 ++ drivers/crypto/Makefile | 1 + drivers/crypto/exynos-rng.c | 390 ++++++++++++++++++++++++++++++++++++ 9 files changed, 426 insertions(+), 246 deletions(-) delete mode 100644 drivers/char/hw_random/exynos-rng.c create mode 100644 drivers/crypto/exynos-rng.c -- 2.9.3
