[PATCH 3/3] i2c: octeon: Handle watchdog timeout

Piyush Malgujar
2023-03-30T13:43:41Z

From: Suneel Garapati <sgarapati@marvell.com>

Status code 0xF0 refers to expiry of TWSI controller
access watchdog and needs bus monitor reset using MODE
register.

Signed-off-by: Suneel Garapati <sgarapati@marvell.com>
Signed-off-by: Piyush Malgujar <pmalgujar@marvell.com>
---
drivers/i2c/busses/i2c-octeon-core.c | 8 ++++++++
drivers/i2c/busses/i2c-octeon-core.h | 1 +
2 files changed, 9 insertions(+)

diff --git a/drivers/i2c/busses/i2c-octeon-core.c b/drivers/i2c/busses/i2c-octeon-core.c
index 7c49dc8ccbd2ef05fec675d282193b98f2b69835..3482db7165f243232937e0af148fe996858e9f2e 100644
--- a/drivers/i2c/busses/i2c-octeon-core.c
+++ b/drivers/i2c/busses/i2c-octeon-core.c
@@ -187,6 +187,7 @@ static int octeon_i2c_hlc_wait(struct octeon_i2c *i2c)
static int octeon_i2c_check_status(struct octeon_i2c *i2c, int final_read)
{
u8 stat;
+ u64 mode;

/*
* This is ugly... in HLC mode the status is not in the status register
@@ -249,6 +250,13 @@ static int octeon_i2c_check_status(struct octeon_i2c *i2c, int final_read)
case STAT_RXADDR_NAK:
case STAT_AD2W_NAK:
return -ENXIO;
+
+ case STAT_WDOG_TOUT:
+ mode = __raw_readq(i2c->twsi_base + MODE(i2c));
+ /* Set BUS_MON_RST to reset bus monitor */
+ mode |= BIT(3);
+ octeon_i2c_writeq_flush(mode, i2c->twsi_base + MODE(i2c));
+ return -EIO;
default:
dev_err(i2c->dev, "unhandled state: %d\n", stat);
return -EIO;
diff --git a/drivers/i2c/busses/i2c-octeon-core.h b/drivers/i2c/busses/i2c-octeon-core.h
index 89d7d3bb8e30bd5787978d17d5a9b20ab0d41e22..a8d1bf9e89b8b0d21f52ff9f77f0ecf5263b5843 100644
--- a/drivers/i2c/busses/i2c-octeon-core.h
+++ b/drivers/i2c/busses/i2c-octeon-core.h
@@ -72,6 +72,7 @@
#define STAT_SLAVE_ACK 0xC8
#define STAT_AD2W_ACK 0xD0
#define STAT_AD2W_NAK 0xD8
+#define STAT_WDOG_TOUT 0xF0
#define STAT_IDLE 0xF8

/* TWSI_INT values */
--
2.17.1