[PATCH 1/3] i2c: octeon: Add error state recovery

[Paul Cercueil <paul.cercueil@bootlin.com>]

From: Tanmay Jagdale <tanmay@marvell.com>

Whenever a Bus Error state occurs, trigger a software recovery to
attempt to return to a working state.

Signed-off-by: Tanmay Jagdale <tanmay@marvell.com>
Co-developed-by: Paul Cercueil <paul.cercueil@bootlin.com>
Signed-off-by: Paul Cercueil <paul.cercueil@bootlin.com>
---
 drivers/i2c/busses/i2c-octeon-core.c | 27 ++++++++++++++-------------
 1 file changed, 14 insertions(+), 13 deletions(-)

diff --git a/drivers/i2c/busses/i2c-octeon-core.c b/drivers/i2c/busses/i2c-octeon-core.c
index 93a49e4637ec..9f72ec1feaa0 100644
--- a/drivers/i2c/busses/i2c-octeon-core.c
+++ b/drivers/i2c/busses/i2c-octeon-core.c
@@ -205,6 +205,17 @@ static int octeon_i2c_hlc_wait(struct octeon_i2c *i2c)
 	return 0;
 }
 
+static int octeon_i2c_recovery(struct octeon_i2c *i2c)
+{
+	int ret;
+
+	ret = i2c_recover_bus(&i2c->adap);
+	if (ret)
+		/* recover failed, try hardware re-init */
+		ret = octeon_i2c_init_lowlevel(i2c);
+	return ret;
+}
+
 static int octeon_i2c_check_status(struct octeon_i2c *i2c, int final_read)
 {
 	u8 stat;
@@ -265,8 +276,9 @@ static int octeon_i2c_check_status(struct octeon_i2c *i2c, int final_read)
 		return -EOPNOTSUPP;
 
 	case STAT_TXDATA_NAK:
-	case STAT_BUS_ERROR:
 		return -EIO;
+	case STAT_BUS_ERROR:
+		return octeon_i2c_recovery(i2c) ? -EIO : -EAGAIN;
 	case STAT_TXADDR_NAK:
 	case STAT_RXADDR_NAK:
 	case STAT_AD2W_NAK:
@@ -277,24 +289,13 @@ static int octeon_i2c_check_status(struct octeon_i2c *i2c, int final_read)
 		/* Set BUS_MON_RST to reset bus monitor */
 		mode |= BUS_MON_RST_MASK;
 		octeon_i2c_writeq_flush(mode, i2c->twsi_base + OCTEON_REG_MODE(i2c));
-		return -EIO;
+		return octeon_i2c_recovery(i2c) ? -EIO : -EAGAIN;
 	default:
 		dev_err(i2c->dev, "unhandled state: %d\n", stat);
 		return -EIO;
 	}
 }
 
-static int octeon_i2c_recovery(struct octeon_i2c *i2c)
-{
-	int ret;
-
-	ret = i2c_recover_bus(&i2c->adap);
-	if (ret)
-		/* recover failed, try hardware re-init */
-		ret = octeon_i2c_init_lowlevel(i2c);
-	return ret;
-}
-
 /**
  * octeon_i2c_start - send START to the bus
  * @i2c: The struct octeon_i2c
-- 
2.47.3