On Tue, Aug 11, 2020 at 4:11 PM John Stultz <john.stultz@xxxxxxxxxx> wrote: > > On Wed, Mar 20, 2019 at 2:49 AM Rajendra Nayak <rnayak@xxxxxxxxxxxxxx> wrote: > > > > geni serial needs to express a perforamnce state requirement on CX > > depending on the frequency of the clock rates. Use OPP table from > > DT to register with OPP framework and use dev_pm_opp_set_rate() to > > set the clk/perf state. > > > > Signed-off-by: Rajendra Nayak <rnayak@xxxxxxxxxxxxxx> > > Signed-off-by: Stephen Boyd <swboyd@xxxxxxxxxxxx> > > --- > > drivers/tty/serial/qcom_geni_serial.c | 15 +++++++++++++-- > > 1 file changed, 13 insertions(+), 2 deletions(-) > > > > Hey, > I just wanted to follow up on this patch, as I've bisected it > (a5819b548af0) down as having broken qca bluetooth on the Dragonboard > 845c. > > I haven't yet had time to debug it yet, but wanted to raise the issue > in case anyone else has seen similar trouble. So I dug in a bit further, and this chunk seems to be causing the issue: > @@ -961,7 +963,7 @@ static void qcom_geni_serial_set_termios(struct uart_port *uport, > goto out_restart_rx; > > uport->uartclk = clk_rate; > - clk_set_rate(port->se.clk, clk_rate); > + dev_pm_opp_set_rate(port->dev, clk_rate); > ser_clk_cfg = SER_CLK_EN; > ser_clk_cfg |= clk_div << CLK_DIV_SHFT; > With that applied, I see the following errors in dmesg and bluetooth fails to function: [ 4.763467] qcom_geni_serial 898000.serial: dev_pm_opp_set_rate: failed to find OPP for freq 102400000 (-34) [ 4.773493] qcom_geni_serial 898000.serial: dev_pm_opp_set_rate: failed to find OPP for freq 102400000 (-34) With just that chunk reverted on linus/HEAD, bluetooth seems to work ok. thanks -john
