2019-01-16 04:16:32

by Alexandre Belloni

Subject: [PATCH] tty: serial: lpc32xx_hs: fix missing console boot messages

When probing the HSUART, it is put in loopback mode in order to prevent a
potential issue that may happen on RX (Errata HSUART.1).

serial_lpc32xx_startup() moves it out of loopback mode but this is too late
to get the kernel boot messages before userspace opens the device.

Also get out of loopback mode in lpc32xx_hsuart_console_setup().

Signed-off-by: Alexandre Belloni <[email protected]>
---
drivers/tty/serial/lpc32xx_hs.c | 4 ++++
1 file changed, 4 insertions(+)

diff --git a/drivers/tty/serial/lpc32xx_hs.c b/drivers/tty/serial/lpc32xx_hs.c
index d1d73261575b..f4e27d0ad947 100644
--- a/drivers/tty/serial/lpc32xx_hs.c
+++ b/drivers/tty/serial/lpc32xx_hs.c
@@ -151,6 +151,8 @@ static void lpc32xx_hsuart_console_write(struct console *co, const char *s,
local_irq_restore(flags);
}

+static void lpc32xx_loopback_set(resource_size_t mapbase, int state);
+
static int __init lpc32xx_hsuart_console_setup(struct console *co,
char *options)
{
@@ -170,6 +172,8 @@ static int __init lpc32xx_hsuart_console_setup(struct console *co,
if (options)
uart_parse_options(options, &baud, &parity, &bits, &flow);

+ lpc32xx_loopback_set(port->mapbase, 0); /* get out of loopback mode */
+
return uart_set_options(port, co, baud, parity, bits, flow);
}

--
2.20.1

2019-01-22 22:41:19

by Vladimir Zapolskiy

Subject: Re: [PATCH] tty: serial: lpc32xx_hs: fix missing console boot messages

Hi Alexandre,

On 01/15/2019 07:18 PM, Alexandre Belloni wrote:
> When probing the HSUART, it is put in loopback mode in order to prevent a
> potential issue that may happen on RX (Errata HSUART.1).
>
> serial_lpc32xx_startup() moves it out of loopback mode but this is too late
> to get the kernel boot messages before userspace opens the device.
>
> Also get out of loopback mode in lpc32xx_hsuart_console_setup().
>
> Signed-off-by: Alexandre Belloni <[email protected]>

the change looks good, thank you.

Acked-by: Vladimir Zapolskiy <[email protected]>

--
Best wishes,
Vladimir