diff options
Diffstat (limited to 'target/linux/bcm27xx/patches-5.4/950-0843-serial-8250-bcm2835aux-defer-if-clock-is-zero.patch')
| -rw-r--r-- | target/linux/bcm27xx/patches-5.4/950-0843-serial-8250-bcm2835aux-defer-if-clock-is-zero.patch | 28 |
1 files changed, 28 insertions, 0 deletions
diff --git a/target/linux/bcm27xx/patches-5.4/950-0843-serial-8250-bcm2835aux-defer-if-clock-is-zero.patch b/target/linux/bcm27xx/patches-5.4/950-0843-serial-8250-bcm2835aux-defer-if-clock-is-zero.patch new file mode 100644 index 0000000000..b421ba9cdc --- /dev/null +++ b/target/linux/bcm27xx/patches-5.4/950-0843-serial-8250-bcm2835aux-defer-if-clock-is-zero.patch @@ -0,0 +1,28 @@ +From 80163961af8e31a2045271c5a12adaae620445e1 Mon Sep 17 00:00:00 2001 +From: Phil Elwell <phil@raspberrypi.com> +Date: Thu, 2 Jul 2020 13:53:20 +0100 +Subject: [PATCH] serial: 8250: bcm2835aux - defer if clock is zero + +See: https://github.com/raspberrypi/linux/issues/3700 + +Signed-off-by: Phil Elwell <phil@raspberrypi.com> +--- + drivers/tty/serial/8250/8250_bcm2835aux.c | 7 +++++++ + 1 file changed, 7 insertions(+) + +--- a/drivers/tty/serial/8250/8250_bcm2835aux.c ++++ b/drivers/tty/serial/8250/8250_bcm2835aux.c +@@ -92,6 +92,13 @@ static int bcm2835aux_serial_probe(struc + */ + data->uart.port.uartclk = clk_get_rate(data->clk) * 2; + ++ /* The clock is only queried at probe time, which means we get one shot ++ * at this. A zero clock is never going to work and is almost certainly ++ * due to a parent not being ready, so prefer to defer. ++ */ ++ if (!data->uart.port.uartclk) ++ return -EPROBE_DEFER; ++ + /* register the port */ + ret = serial8250_register_8250_port(&data->uart); + if (ret < 0) { |