[PATCH 5.13 592/800] clk: si5341: Check for input clock presence and PLL lock on startup
From: Greg Kroah-Hartman
Date: Mon Jul 12 2021 - 04:51:14 EST
From: Robert Hancock <robert.hancock@xxxxxxxxxx>
[ Upstream commit 71dcc4d1f7d2ad97ff7ab831281bc6893ff713a2 ]
After initializing the device, wait for it to report that the input
clock is present and the PLL has locked before declaring success.
Fixes: 3044a860fd ("clk: Add Si5341/Si5340 driver")
Signed-off-by: Robert Hancock <robert.hancock@xxxxxxxxxx>
Link: https://lore.kernel.org/r/20210325192643.2190069-5-robert.hancock@xxxxxxxxxx
Signed-off-by: Stephen Boyd <sboyd@xxxxxxxxxx>
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
---
drivers/clk/clk-si5341.c | 26 ++++++++++++++++++++++++++
1 file changed, 26 insertions(+)
diff --git a/drivers/clk/clk-si5341.c b/drivers/clk/clk-si5341.c
index ac1ccec2b681..da40b90c2aa8 100644
--- a/drivers/clk/clk-si5341.c
+++ b/drivers/clk/clk-si5341.c
@@ -92,6 +92,9 @@ struct clk_si5341_output_config {
#define SI5341_PN_BASE 0x0002
#define SI5341_DEVICE_REV 0x0005
#define SI5341_STATUS 0x000C
+#define SI5341_LOS 0x000D
+#define SI5341_STATUS_STICKY 0x0011
+#define SI5341_LOS_STICKY 0x0012
#define SI5341_SOFT_RST 0x001C
#define SI5341_IN_SEL 0x0021
#define SI5341_DEVICE_READY 0x00FE
@@ -99,6 +102,12 @@ struct clk_si5341_output_config {
#define SI5341_IN_EN 0x0949
#define SI5341_INX_TO_PFD_EN 0x094A
+/* Status bits */
+#define SI5341_STATUS_SYSINCAL BIT(0)
+#define SI5341_STATUS_LOSXAXB BIT(1)
+#define SI5341_STATUS_LOSREF BIT(2)
+#define SI5341_STATUS_LOL BIT(3)
+
/* Input selection */
#define SI5341_IN_SEL_MASK 0x06
#define SI5341_IN_SEL_SHIFT 1
@@ -1416,6 +1425,7 @@ static int si5341_probe(struct i2c_client *client,
unsigned int i;
struct clk_si5341_output_config config[SI5341_MAX_NUM_OUTPUTS];
bool initialization_required;
+ u32 status;
data = devm_kzalloc(&client->dev, sizeof(*data), GFP_KERNEL);
if (!data)
@@ -1583,6 +1593,22 @@ static int si5341_probe(struct i2c_client *client,
return err;
}
+ /* wait for device to report input clock present and PLL lock */
+ err = regmap_read_poll_timeout(data->regmap, SI5341_STATUS, status,
+ !(status & (SI5341_STATUS_LOSREF | SI5341_STATUS_LOL)),
+ 10000, 250000);
+ if (err) {
+ dev_err(&client->dev, "Error waiting for input clock or PLL lock\n");
+ return err;
+ }
+
+ /* clear sticky alarm bits from initialization */
+ err = regmap_write(data->regmap, SI5341_STATUS_STICKY, 0);
+ if (err) {
+ dev_err(&client->dev, "unable to clear sticky status\n");
+ return err;
+ }
+
/* Free the names, clk framework makes copies */
for (i = 0; i < data->num_synth; ++i)
devm_kfree(&client->dev, (void *)synth_clock_names[i]);
--
2.30.2