[PATCH v5 6/8] serial: msm-geni: Enable SE clk in probe

[Casey Connolly]

From: Stephen Boyd <swboyd at chromium.org>

Enable the serial engine clk in probe so that this driver can work on
platforms that don't already initialize the clk for this device before
this driver runs. This fixes a problem I see on Coreboot platforms like
Trogdor where the UART hardware isn't enabled by coreboot unless the
serial console build is used.

Signed-off-by: Stephen Boyd <swboyd at chromium.org>
---
 drivers/serial/serial_msm_geni.c | 26 ++++++++++++--------------
 1 file changed, 12 insertions(+), 14 deletions(-)

diff --git a/drivers/serial/serial_msm_geni.c b/drivers/serial/serial_msm_geni.c
index 44603ead77cd9f7948a2bf52ebddfebbfeb9f1c2..35e0029144be7948eb5ab0da5a2d1317a08fb0c5 100644
--- a/drivers/serial/serial_msm_geni.c
+++ b/drivers/serial/serial_msm_geni.c
@@ -130,8 +130,9 @@ DECLARE_GLOBAL_DATA_PTR;
 struct msm_serial_data {
 	phys_addr_t base;
 	u32 baud;
 	u32 oversampling;
+	struct clk *se;
 };
 
 unsigned long root_freq[] = {7372800,  14745600, 19200000, 29491200,
 			     32000000, 48000000, 64000000, 80000000,
@@ -180,21 +181,8 @@ static int get_clk_div_rate(u32 baud, u64 sampling_rate, u32 *clk_div)
 	*clk_div = ser_clk / desired_clk;
 	return ser_clk;
 }
 
-static int geni_serial_set_clock_rate(struct udevice *dev, u64 rate)
-{
-	struct clk *clk;
-	int ret;
-
-	clk = devm_clk_get(dev, NULL);
-	if (IS_ERR(clk))
-		return PTR_ERR(clk);
-
-	ret = clk_set_rate(clk, rate);
-	return ret;
-}
-
 /**
  * geni_se_get_tx_fifo_depth() - Get the TX fifo depth of the serial engine
  * @base:	Pointer to the concerned serial engine.
  *
@@ -251,9 +239,9 @@ static int msm_serial_setbrg(struct udevice *dev, int baud)
 
 	priv->baud = baud;
 
 	clk_rate = get_clk_div_rate(baud, priv->oversampling, &clk_div);
-	ret = geni_serial_set_clock_rate(dev, clk_rate);
+	ret = clk_set_rate(priv->se, clk_rate);
 	if (ret < 0) {
 		pr_err("%s: Couldn't set clock rate: %d\n", __func__, ret);
 		return ret;
 	}
@@ -560,8 +548,18 @@ static inline void geni_serial_init(struct udevice *dev)
 static int msm_serial_probe(struct udevice *dev)
 {
 	struct msm_serial_data *priv = dev_get_priv(dev);
 	int ret;
+	struct clk *clk;
+
+	clk = devm_clk_get(dev, NULL);
+	if (IS_ERR(clk))
+		return PTR_ERR(clk);
+	priv->se = clk;
+
+	ret = clk_enable(clk);
+	if (ret)
+		return ret;
 
 	ret = geni_set_oversampling(dev);
 	if (ret < 0)
 		return ret;

-- 
2.50.0