• Tony Lindgren's avatar
    serial: 8250_omap: Handle optional overrun-throttle-ms property · 1fe0e1fa
    Tony Lindgren authored
    Handle optional overrun-throttle-ms property as done for 8250_fsl in commit
    6d7f677a
    
     ("serial: 8250: Rate limit serial port rx interrupts during
    input overruns"). This can be used to rate limit the UART interrupts on
    noisy lines that end up producing messages like the following:
    
    ttyS ttyS2: 4 input overrun(s)
    
    At least on droid4, the multiplexed USB and UART port is left to UART mode
    by the bootloader for a debug console, and if a USB charger is connected
    on boot, we get noise on the UART until the PMIC related drivers for PHY
    and charger are loaded.
    
    With this patch and overrun-throttle-ms = <500> we avoid the extra rx
    interrupts.
    
    Cc: Carl Philipp Klemm <philipp@uvos.xyz>
    Cc: Merlijn Wajer <merlijn@wizzup.org>
    Cc: Pavel Machek <pavel@ucw.cz>
    Cc: Sebastian Reichel <sre@kernel.org>
    Cc: Vignesh Raghavendra <vigneshr@ti.com>
    Signed-off-by: default avatarTony Lindgren <tony@atomide.com>
    Link: https://lore.kernel.org/r/20210727103533.51547-2-tony@atomide.com
    
    Signed-off-by: default avatarGreg Kroah-Hartman <gregkh@linuxfoundation.org>
    1fe0e1fa
8250_omap.c 44.4 KB