6.4-stable review patch. If anyone has any objections, please let me know.
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From: Johan Hovold johan+linaro@kernel.org
commit 8ece7b754bc34ffd7fcc8269ccb9128e72ca76d8 upstream.
The operating-performance-point vote needs to be dropped when shutting down the port to avoid wasting power by keeping resources like power domains in an unnecessarily high performance state (e.g. when a UART connected Bluetooth controller is not in use).
Fixes: a5819b548af0 ("tty: serial: qcom_geni_serial: Use OPP API to set clk/perf state") Cc: stable@vger.kernel.org # 5.9 Cc: Rajendra Nayak quic_rjendra@quicinc.com Cc: Matthias Kaehlcke mka@chromium.org Signed-off-by: Johan Hovold johan+linaro@kernel.org Acked-by: Konrad Dybcio konrad.dybcio@linaro.org Link: https://lore.kernel.org/r/20230714130214.14552-2-johan+linaro@kernel.org Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org --- drivers/tty/serial/qcom_geni_serial.c | 5 +++++ 1 file changed, 5 insertions(+)
--- a/drivers/tty/serial/qcom_geni_serial.c +++ b/drivers/tty/serial/qcom_geni_serial.c @@ -126,6 +126,7 @@ struct qcom_geni_serial_port { dma_addr_t rx_dma_addr; bool setup; unsigned int baud; + unsigned long clk_rate; void *rx_buf; u32 loopback; bool brk; @@ -1244,6 +1245,7 @@ static void qcom_geni_serial_set_termios baud * sampling_rate, clk_rate, clk_div);
uport->uartclk = clk_rate; + port->clk_rate = 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; @@ -1508,10 +1510,13 @@ static void qcom_geni_serial_pm(struct u
if (new_state == UART_PM_STATE_ON && old_state == UART_PM_STATE_OFF) { geni_icc_enable(&port->se); + if (port->clk_rate) + dev_pm_opp_set_rate(uport->dev, port->clk_rate); geni_se_resources_on(&port->se); } else if (new_state == UART_PM_STATE_OFF && old_state == UART_PM_STATE_ON) { geni_se_resources_off(&port->se); + dev_pm_opp_set_rate(uport->dev, 0); geni_icc_disable(&port->se); } }