From: Hugo Villeneuve <hvilleneuve@xxxxxxxxxxxx> Make sure we wait at least 3us before initiating communication with the device after reset. Signed-off-by: Hugo Villeneuve <hvilleneuve@xxxxxxxxxxxx> Reviewed-by: Lech Perczak <lech.perczak@xxxxxxxxxxxxxxx> Tested-by: Lech Perczak <lech.perczak@xxxxxxxxxxxxxxx> --- drivers/tty/serial/sc16is7xx.c | 6 ++++++ 1 file changed, 6 insertions(+) diff --git a/drivers/tty/serial/sc16is7xx.c b/drivers/tty/serial/sc16is7xx.c index 388c1d490853..9b2d58023c55 100644 --- a/drivers/tty/serial/sc16is7xx.c +++ b/drivers/tty/serial/sc16is7xx.c @@ -1521,6 +1521,12 @@ static int sc16is7xx_probe(struct device *dev, regmap_write(s->regmap, SC16IS7XX_IOCONTROL_REG << SC16IS7XX_REG_SHIFT, SC16IS7XX_IOCONTROL_SRESET_BIT); + /* + * After reset, the host must wait at least 3us before initializing a + * communication with the device. + */ + usleep_range(5, 10); + for (i = 0; i < devtype->nr_uart; ++i) { s->p[i].line = i; /* Initialize port data */ -- 2.30.2