[PATCH v2 5/9] serial: qcom-geni: Use geni_se_set_rate() for source clock configuration

On the SA8255P platform there is no Linux clock handler for the SE
source clock, so the driver has no way to compute the divider needed
for a requested baud rate. To work around this, firmware instead
exposes the SE HW supported source clock frequencies as OPPs on the
perf domain device.

geni_se_domain_attach() now populates clk_perf_tbl from
the performance-domain OPP table, allowing firmware-managed
platforms to use geni_se_clk_freq_match().

Call geni_serial_set_rate() unconditionally from
qcom_geni_serial_set_termios(), and use geni_se_set_rate() instead of
dev_pm_opp_set_rate() so clock programming is handled centrally by
the GENI core, independent of the underlying clock-control mechanism.

Signed-off-by: Praveen Talari <[email protected]>
---
 drivers/tty/serial/qcom_geni_serial.c | 26 ++++++++++++++------------
 1 file changed, 14 insertions(+), 12 deletions(-)

diff --git a/drivers/tty/serial/qcom_geni_serial.c b/drivers/tty/serial/qcom_geni_serial.c
index 3633723acef8..23ecd137c521 100644
--- a/drivers/tty/serial/qcom_geni_serial.c
+++ b/drivers/tty/serial/qcom_geni_serial.c
@@ -114,7 +114,6 @@ struct qcom_geni_device_data {
 	bool console;
 	enum geni_se_xfer_mode mode;
 	int (*resources_init)(struct geni_se *se);
-	int (*set_rate)(struct geni_se *se, unsigned long baud);
 	int (*power_on)(struct geni_se *se);
 	int (*power_off)(struct geni_se *se);
 };
@@ -1474,7 +1473,10 @@ static int geni_serial_set_rate(struct geni_se *se, unsigned long baud)
 
 	uport->uartclk = clk_rate;
 	port->clk_rate = clk_rate;
-	dev_pm_opp_set_rate(uport->dev, clk_rate);
+	ret = geni_se_set_rate(&port->se, clk_rate);
+	if (ret)
+		return ret;
+
 	ser_clk_cfg = SER_CLK_EN;
 	ser_clk_cfg |= clk_div << CLK_DIV_SHFT;
 
@@ -1513,7 +1515,7 @@ static void qcom_geni_serial_set_termios(struct uart_port *uport,
 	/* baud rate */
 	baud = uart_get_baud_rate(uport, termios, old, 300, 8000000);
 
-	ret = port->dev_data->set_rate(&port->se, baud);
+	ret = geni_serial_set_rate(&port->se, baud);
 	if (ret)
 		return;
 
@@ -2039,15 +2041,19 @@ static void qcom_geni_serial_remove(struct platform_device *pdev)
 static int __maybe_unused qcom_geni_serial_runtime_suspend(struct device *dev)
 {
 	struct qcom_geni_serial_port *port = dev_get_drvdata(dev);
+	int ret;
 
-	return port->dev_data->power_off ?
-	       port->dev_data->power_off(&port->se) : 0;
+	ret = port->dev_data->power_off ?
+	      port->dev_data->power_off(&port->se) : 0;
+	if (ret)
+		return ret;
+
+	return geni_se_set_rate(&port->se, 0);
 }
 
 static int __maybe_unused qcom_geni_serial_runtime_resume(struct device *dev)
 {
 	struct qcom_geni_serial_port *port = dev_get_drvdata(dev);
-	struct uart_port *uport = &port->uport;
 	int ret;
 
 	if (port->dev_data->power_on) {
@@ -2056,8 +2062,8 @@ static int __maybe_unused qcom_geni_serial_runtime_resume(struct device *dev)
 			return ret;
 	}
 
-	if (port->se.has_opp && port->clk_rate)
-		return dev_pm_opp_set_rate(uport->dev, port->clk_rate);
+	if (port->clk_rate)
+		return geni_se_set_rate(&port->se, port->clk_rate);
 
 	return 0;
 }
@@ -2116,7 +2122,6 @@ static const struct qcom_geni_device_data qcom_geni_console_data = {
 	.console = true,
 	.mode = GENI_SE_FIFO,
 	.resources_init = geni_se_resources_init,
-	.set_rate = geni_serial_set_rate,
 	.power_on = geni_se_resources_activate,
 	.power_off = geni_se_resources_deactivate,
 };
@@ -2125,7 +2130,6 @@ static const struct qcom_geni_device_data sa8255p_qcom_geni_console_data = {
 	.console = true,
 	.mode = GENI_SE_FIFO,
 	.resources_init = geni_se_domain_attach,
-	.set_rate = geni_se_set_perf_level,
 };
 #endif
 
@@ -2133,7 +2137,6 @@ static const struct qcom_geni_device_data qcom_geni_uart_data = {
 	.console = false,
 	.mode = GENI_SE_DMA,
 	.resources_init = geni_se_resources_init,
-	.set_rate = geni_serial_set_rate,
 	.power_on = geni_se_resources_activate,
 	.power_off = geni_se_resources_deactivate,
 };
@@ -2142,7 +2145,6 @@ static const struct qcom_geni_device_data sa8255p_qcom_geni_uart_data = {
 	.console = false,
 	.mode = GENI_SE_DMA,
 	.resources_init = geni_se_domain_attach,
-	.set_rate = geni_se_set_perf_level,
 };
 
 static const struct dev_pm_ops qcom_geni_serial_pm_ops = {

-- 
2.34.1