From 60f361722ad2ae5ee667d0b0545d40c42f754daf Mon Sep 17 00:00:00 2001 From: Lukas Wunner Date: Sun, 11 Sep 2022 10:22:01 +0200 Subject: [PATCH] serial: fsl_lpuart: Reset prior to registration MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Since commit bd5305dcabbc ("tty: serial: fsl_lpuart: do software reset for imx7ulp and imx8qxp"), certain i.MX UARTs are reset after they've already been registered. Register state may thus be clobbered after user space has begun to open and access the UART. Avoid by performing the reset prior to registration. Fixes: bd5305dcabbc ("tty: serial: fsl_lpuart: do software reset for imx7ulp and imx8qxp") Cc: stable@vger.kernel.org # v5.15+ Cc: Fugang Duan Cc: Sherry Sun Reviewed-by: Ilpo Järvinen Signed-off-by: Lukas Wunner Link: https://lore.kernel.org/r/72fb646c1b0b11c989850c55f52f9ff343d1b2fa.1662884345.git.lukas@wunner.de Signed-off-by: Greg Kroah-Hartman --- drivers/tty/serial/fsl_lpuart.c | 9 +++++---- 1 file changed, 5 insertions(+), 4 deletions(-) diff --git a/drivers/tty/serial/fsl_lpuart.c b/drivers/tty/serial/fsl_lpuart.c index b20f6f2fa51c..fbc4b071b330 100644 --- a/drivers/tty/serial/fsl_lpuart.c +++ b/drivers/tty/serial/fsl_lpuart.c @@ -2724,14 +2724,15 @@ static int lpuart_probe(struct platform_device *pdev) lpuart_reg.cons = LPUART_CONSOLE; handler = lpuart_int; } - ret = uart_add_one_port(&lpuart_reg, &sport->port); - if (ret) - goto failed_attach_port; ret = lpuart_global_reset(sport); if (ret) goto failed_reset; + ret = uart_add_one_port(&lpuart_reg, &sport->port); + if (ret) + goto failed_attach_port; + ret = uart_get_rs485_mode(&sport->port); if (ret) goto failed_get_rs485; @@ -2747,9 +2748,9 @@ static int lpuart_probe(struct platform_device *pdev) failed_irq_request: failed_get_rs485: -failed_reset: uart_remove_one_port(&lpuart_reg, &sport->port); failed_attach_port: +failed_reset: lpuart_disable_clks(sport); return ret; }