From 2712625200ed69c642b9abc3a403830c4643364c Mon Sep 17 00:00:00 2001 From: Torin Cooper-Bennun Date: Fri, 26 Feb 2021 16:34:41 +0000 Subject: [PATCH] can: tcan4x5x: tcan4x5x_init(): fix initialization - clear MRAM before entering Normal Mode This patch prevents a potentially destructive race condition. The device is fully operational on the bus after entering Normal Mode, so zeroing the MRAM after entering this mode may lead to loss of information, e.g. new received messages. This patch fixes the problem by first initializing the MRAM, then bringing the device into Normale Mode. Fixes: 5443c226ba91 ("can: tcan4x5x: Add tcan4x5x driver to the kernel") Link: https://lore.kernel.org/r/20210226163440.313628-1-torin@maxiluxsystems.com Suggested-by: Marc Kleine-Budde Signed-off-by: Torin Cooper-Bennun Signed-off-by: Marc Kleine-Budde --- drivers/net/can/m_can/tcan4x5x-core.c | 6 +++--- 1 file changed, 3 insertions(+), 3 deletions(-) diff --git a/drivers/net/can/m_can/tcan4x5x-core.c b/drivers/net/can/m_can/tcan4x5x-core.c index b7caec769ddb..4147cecfbbd6 100644 --- a/drivers/net/can/m_can/tcan4x5x-core.c +++ b/drivers/net/can/m_can/tcan4x5x-core.c @@ -237,14 +237,14 @@ static int tcan4x5x_init(struct m_can_classdev *cdev) if (ret) return ret; + /* Zero out the MCAN buffers */ + m_can_init_ram(cdev); + ret = regmap_update_bits(tcan4x5x->regmap, TCAN4X5X_CONFIG, TCAN4X5X_MODE_SEL_MASK, TCAN4X5X_MODE_NORMAL); if (ret) return ret; - /* Zero out the MCAN buffers */ - m_can_init_ram(cdev); - return ret; } -- 2.39.5