From: Tobias Schramm Date: Fri, 30 Dec 2022 19:43:15 +0000 (+0100) Subject: mmc: atmel-mci: fix race between stop command and start of next command X-Git-Tag: baikal/mips/sdk5.8.2~128 X-Git-Url: https://git.baikalelectronics.ru/sdk/?a=commitdiff_plain;h=bab2751fbe914beb6dc1d8013fb8dae6366ad133;p=kernel.git mmc: atmel-mci: fix race between stop command and start of next command [ Upstream commit eca5bd666b0aa7dc0bca63292e4778968241134e ] This commit fixes a race between completion of stop command and start of a new command. Previously the command ready interrupt was enabled before stop command was written to the command register. This caused the command ready interrupt to fire immediately since the CMDRDY flag is asserted constantly while there is no command in progress. Consequently the command state machine will immediately advance to the next state when the tasklet function is executed again, no matter actual completion state of the stop command. Thus a new command can then be dispatched immediately, interrupting and corrupting the stop command on the CMD line. Fix that by dropping the command ready interrupt enable before calling atmci_send_stop_cmd. atmci_send_stop_cmd does already enable the command ready interrupt, no further writes to ATMCI_IER are necessary. Signed-off-by: Tobias Schramm Acked-by: Ludovic Desroches Link: https://lore.kernel.org/r/20221230194315.809903-2-t.schramm@manjaro.org Signed-off-by: Ulf Hansson Signed-off-by: Sasha Levin --- diff --git a/drivers/mmc/host/atmel-mci.c b/drivers/mmc/host/atmel-mci.c index 9c084f64f7dba..4d8f2778d8f9a 100644 --- a/drivers/mmc/host/atmel-mci.c +++ b/drivers/mmc/host/atmel-mci.c @@ -1812,7 +1812,6 @@ static void atmci_tasklet_func(unsigned long priv) atmci_writel(host, ATMCI_IER, ATMCI_NOTBUSY); state = STATE_WAITING_NOTBUSY; } else if (host->mrq->stop) { - atmci_writel(host, ATMCI_IER, ATMCI_CMDRDY); atmci_send_stop_cmd(host, data); state = STATE_SENDING_STOP; } else { @@ -1845,8 +1844,6 @@ static void atmci_tasklet_func(unsigned long priv) * command to send. */ if (host->mrq->stop) { - atmci_writel(host, ATMCI_IER, - ATMCI_CMDRDY); atmci_send_stop_cmd(host, data); state = STATE_SENDING_STOP; } else {