[PATCH V2 14/20] i3c: mipi-i3c-hci: Factor out software reset into helper

[Adrian Hunter <adrian.hunter@intel.com>]

Prepare for future reuse of the reset sequence in other contexts, such as
power management.  Move the software reset logic from i3c_hci_init() into a
dedicated helper function, i3c_hci_software_reset().

Software reset should never fail.  Print an error message if it does.

Signed-off-by: Adrian Hunter <adrian.hunter@intel.com>
---


Changes in V2:

	Add to the commit message a sentence about additional error message
	when a timeout happens


 drivers/i3c/master/mipi-i3c-hci/core.c | 41 ++++++++++++++++++--------
 1 file changed, 29 insertions(+), 12 deletions(-)

diff --git a/drivers/i3c/master/mipi-i3c-hci/core.c b/drivers/i3c/master/mipi-i3c-hci/core.c
index c4b249fde764..3b0609cb7da7 100644
--- a/drivers/i3c/master/mipi-i3c-hci/core.c
+++ b/drivers/i3c/master/mipi-i3c-hci/core.c
@@ -585,6 +585,34 @@ static irqreturn_t i3c_hci_irq_handler(int irq, void *dev_id)
 	return result;
 }
 
+static int i3c_hci_software_reset(struct i3c_hci *hci)
+{
+	u32 regval;
+	int ret;
+
+	/*
+	 * SOFT_RST must be clear before we write to it.
+	 * Then we must wait until it clears again.
+	 */
+	ret = readx_poll_timeout(reg_read, RESET_CONTROL, regval,
+				 !(regval & SOFT_RST), 0, 10 * USEC_PER_MSEC);
+	if (ret) {
+		dev_err(&hci->master.dev, "%s: Software reset stuck\n", __func__);
+		return ret;
+	}
+
+	reg_write(RESET_CONTROL, SOFT_RST);
+
+	ret = readx_poll_timeout(reg_read, RESET_CONTROL, regval,
+				 !(regval & SOFT_RST), 0, 10 * USEC_PER_MSEC);
+	if (ret) {
+		dev_err(&hci->master.dev, "%s: Software reset failed\n", __func__);
+		return ret;
+	}
+
+	return 0;
+}
+
 static int i3c_hci_init(struct i3c_hci *hci)
 {
 	bool size_in_dwords, mode_selector;
@@ -654,18 +682,7 @@ static int i3c_hci_init(struct i3c_hci *hci)
 	if (ret)
 		return ret;
 
-	/*
-	 * Now let's reset the hardware.
-	 * SOFT_RST must be clear before we write to it.
-	 * Then we must wait until it clears again.
-	 */
-	ret = readx_poll_timeout(reg_read, RESET_CONTROL, regval,
-				 !(regval & SOFT_RST), 1, 10000);
-	if (ret)
-		return -ENXIO;
-	reg_write(RESET_CONTROL, SOFT_RST);
-	ret = readx_poll_timeout(reg_read, RESET_CONTROL, regval,
-				 !(regval & SOFT_RST), 1, 10000);
+	ret = i3c_hci_software_reset(hci);
 	if (ret)
 		return -ENXIO;
 
-- 
2.51.0


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