From mboxrd@z Thu Jan 1 00:00:00 1970 From: Alexander Graf Date: Tue, 6 Mar 2018 14:13:26 +0100 Subject: [U-Boot] [PATCH 1/2] serial_bcm283x_mu: Flush RX queue after setting baud rate In-Reply-To: <20180306131327.61174-1-agraf@suse.de> References: <20180306131327.61174-1-agraf@suse.de> Message-ID: <20180306131327.61174-2-agraf@suse.de> List-Id: MIME-Version: 1.0 Content-Type: text/plain; charset="iso-8859-1" Content-Transfer-Encoding: quoted-printable To: u-boot@lists.denx.de After the UART was initialized, we may still have bogus data in the RX queue if it was enabled with incorrect pin muxing before. So let's flush the RX queue whenever we initialize baud rates. This fixes a regression with the dynamic pinmuxing code when enable_uart=3D1 is not set in config.txt. Fixes: caf2233b28 ("bcm283x: Add pinctrl driver") Reported-by: G=C3=B6ran Lundberg Reported-by: Peter Robinson Signed-off-by: Alexander Graf --- drivers/serial/serial_bcm283x_mu.c | 8 +++++++- 1 file changed, 7 insertions(+), 1 deletion(-) diff --git a/drivers/serial/serial_bcm283x_mu.c b/drivers/serial/serial_bcm= 283x_mu.c index 40029fadbc..d87b44e902 100644 --- a/drivers/serial/serial_bcm283x_mu.c +++ b/drivers/serial/serial_bcm283x_mu.c @@ -51,6 +51,8 @@ struct bcm283x_mu_priv { struct bcm283x_mu_regs *regs; }; =20 +static int bcm283x_mu_serial_getc(struct udevice *dev); + static int bcm283x_mu_serial_setbrg(struct udevice *dev, int baudrate) { struct bcm283x_mu_serial_platdata *plat =3D dev_get_platdata(dev); @@ -59,13 +61,17 @@ static int bcm283x_mu_serial_setbrg(struct udevice *dev= , int baudrate) u32 divider; =20 if (plat->skip_init) - return 0; + goto out; =20 divider =3D plat->clock / (baudrate * 8); =20 writel(BCM283X_MU_LCR_DATA_SIZE_8, ®s->lcr); writel(divider - 1, ®s->baud); =20 +out: + /* Flush the RX queue - all data in there is bogus */ + while (bcm283x_mu_serial_getc(dev) !=3D -EAGAIN) ; + return 0; } =20 --=20 2.12.3