On 21/11/17 03:09, Shuyu Wei wrote: > On Mon, Nov 20, 2017 at 06:51:37PM +0100, Heiko St?bner wrote: > >> Also, the rk3188 uarts are definitly not fixed at 24MHz and can use other >> sources as well. So I'm puzzled because at least the serial console on my >> rk3188 radxarock works without issues. >> >> Can you tell us which uart you are failing to control correctly? >> >> >> I do remember that I ran into problems when the set_termios change >> was introduced originally, resulting in the patch >> "serial: 8250_dw: Honor clk_round_rate errors in dw8250_set_termios" [0] >> but that is in mainline for quite some time now. >> >> [0] https://patchwork.kernel.org/patch/9594657/ >> >> >> Heiko > Hi Heiko, > > I'm using ttyS2(uart2). > My board starts to fail on mainline since the exact commit 37c8596, > that's why I try to remove dw8250_set_termios() and it worked. Is this on 4.14 or next? What baud rate is being set, and what rate does clk_round_rate() return in dw8250_set_termios()? Can you try applying this patch series and see if it fixes the problem? https://www.spinics.net/lists/linux-serial/msg27672.html
