| Message ID | 1587132279-27659-1-git-send-email-rnayak@codeaurora.org |
|---|---|
| Headers | show |
| Series | DVFS for IO devices on sdm845 and sc7180 | expand |
Hi Rajendra, On Fri, Apr 17, 2020 at 07:34:23PM +0530, Rajendra Nayak wrote: > geni serial needs to express a perforamnce state requirement on CX > powerdomain 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@codeaurora.org> > Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> > Cc: Akash Asthana <akashast@codeaurora.org> > Cc: linux-serial@vger.kernel.org > --- > drivers/tty/serial/qcom_geni_serial.c | 30 +++++++++++++++++++++++++----- > include/linux/qcom-geni-se.h | 2 ++ > 2 files changed, 27 insertions(+), 5 deletions(-) > > diff --git a/drivers/tty/serial/qcom_geni_serial.c b/drivers/tty/serial/qcom_geni_serial.c > index 6119090..151012c 100644 > --- a/drivers/tty/serial/qcom_geni_serial.c > +++ b/drivers/tty/serial/qcom_geni_serial.c > @@ -9,6 +9,7 @@ > #include <linux/module.h> > #include <linux/of.h> > #include <linux/of_device.h> > +#include <linux/pm_opp.h> > #include <linux/platform_device.h> > #include <linux/pm_runtime.h> > #include <linux/pm_wakeirq.h> > @@ -128,6 +129,7 @@ struct qcom_geni_serial_port { > int wakeup_irq; > bool rx_tx_swap; > bool cts_rts_swap; > + bool opp_table; The name of the variable suggests that it holds a OPP table, something like 'has_opp_table' would be clearer. > }; > > static const struct uart_ops qcom_geni_console_pops; > @@ -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(uport->dev, clk_rate); > ser_clk_cfg = SER_CLK_EN; > ser_clk_cfg |= clk_div << CLK_DIV_SHFT; > > @@ -1198,8 +1200,11 @@ static void qcom_geni_serial_pm(struct uart_port *uport, > if (new_state == UART_PM_STATE_ON && old_state == UART_PM_STATE_OFF) > geni_se_resources_on(&port->se); > else if (new_state == UART_PM_STATE_OFF && > - old_state == UART_PM_STATE_ON) > + old_state == UART_PM_STATE_ON) { > + /* Drop the performance state vote */ > + dev_pm_opp_set_rate(uport->dev, 0); > geni_se_resources_off(&port->se); > + } > } > > static const struct uart_ops qcom_geni_console_pops = { > @@ -1318,13 +1323,20 @@ static int qcom_geni_serial_probe(struct platform_device *pdev) > if (of_property_read_bool(pdev->dev.of_node, "cts-rts-swap")) > port->cts_rts_swap = true; > > + port->se.opp = dev_pm_opp_set_clkname(&pdev->dev, "se"); > + if (IS_ERR(port->se.opp)) > + return PTR_ERR(port->se.opp); > + /* OPP table is optional */ > + if (!dev_pm_opp_of_add_table(&pdev->dev)) Even if the OPP table is optional you probably want to fail if the error is anything other than -ENODEV ("'operating-points' property is not found or is invalid data in device node."). > diff --git a/include/linux/qcom-geni-se.h b/include/linux/qcom-geni-se.h > index dd46494..737e713 100644 > --- a/include/linux/qcom-geni-se.h > +++ b/include/linux/qcom-geni-se.h > @@ -24,6 +24,7 @@ enum geni_se_protocol_type { > > struct geni_wrapper; > struct clk; > +struct opp_table; > > /** > * struct geni_se - GENI Serial Engine > @@ -39,6 +40,7 @@ struct geni_se { > struct device *dev; > struct geni_wrapper *wrapper; > struct clk *clk; > + struct opp_table *opp; This name suggests that the variable holds a single OPP ('struct dev_pm_opp'). Most other code uses the name 'opp_table', which also seems a good candidate here.