Commit b9960b90 authored by Suneel Garapati's avatar Suneel Garapati Committed by Andi Shyti
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i2c: octeon: Handle watchdog timeout 



Add watchdog timeout handling to cater to the unhandled warnings
seen during validation on boards with different I2C slaves.
This status code reflects the state that controller couldn't
receive any response from slave while being in non-idle state
and HW recommends to reset before any further bus access.

Signed-off-by: default avatarSuneel Garapati <sgarapati@marvell.com>
Signed-off-by: default avatarPiyush Malgujar <pmalgujar@marvell.com>
Acked-by: default avatarAndi Shyti <andi.shyti@kernel.org>
Signed-off-by: default avatarAndi Shyti <andi.shyti@kernel.org>
parent 0b042c72

drivers/i2c/busses/i2c-octeon-core.c

+8 −0
Original line number Diff line number Diff line
@@ -182,6 +182,7 @@ 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
@@ -244,6 +245,13 @@ 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 + OCTEON_REG_MODE(i2c));

		/* 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;

	default:

		dev_err(i2c->dev, "unhandled state: %d\n", stat);

		return -EIO;

drivers/i2c/busses/i2c-octeon-core.h

+4 −0
Original line number Diff line number Diff line
@@ -73,6 +73,7 @@ 
#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 */
@@ -107,6 +108,9 @@ struct octeon_i2c_reg_offset { 
#define TWSX_MODE_HS_MODE	BIT(0)

#define TWSX_MODE_HS_MASK	(TWSX_MODE_REFCLK_SRC | TWSX_MODE_HS_MODE)



/* Set BUS_MON_RST to reset bus monitor */

#define BUS_MON_RST_MASK	BIT(3)



struct octeon_i2c {

	wait_queue_head_t queue;

	struct i2c_adapter adap;