Commit 92e73d80 authored by William A. Kennington III's avatar William A. Kennington III Committed by Wolfram Sang
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i2c: npcm7xx: Fix callback completion ordering 



Sometimes, our completions race with new master transfers and override
the bus->operation and bus->master_or_slave variables. This causes
transactions to timeout and kernel crashes less frequently.

To remedy this, we re-order all completions to the very end of the
function.

Fixes: 56a1485b ("i2c: npcm7xx: Add Nuvoton NPCM I2C controller driver")
Signed-off-by: default avatarWilliam A. Kennington III <william@wkennington.com>
Reviewed-by: default avatarTali Perry <tali.perry1@gmail.com>
Signed-off-by: default avatarWolfram Sang <wsa@kernel.org>
parent b13e59e7

drivers/i2c/busses/i2c-npcm7xx.c

+7 −10
Original line number Diff line number Diff line
@@ -694,6 +694,7 @@ static void npcm_i2c_callback(struct npcm_i2c *bus, 
{

	struct i2c_msg *msgs;

	int msgs_num;

	bool do_complete = false;



	msgs = bus->msgs;

	msgs_num = bus->msgs_num;
@@ -722,23 +723,17 @@ static void npcm_i2c_callback(struct npcm_i2c *bus, 
				 msgs[1].flags & I2C_M_RD)

				msgs[1].len = info;

		}

		if (completion_done(&bus->cmd_complete) == false)

			complete(&bus->cmd_complete);

		do_complete = true;

		break;



	case I2C_NACK_IND:

		/* MASTER transmit got a NACK before tx all bytes */

		bus->cmd_err = -ENXIO;

		if (bus->master_or_slave == I2C_MASTER)

			complete(&bus->cmd_complete);



		do_complete = true;

		break;

	case I2C_BUS_ERR_IND:

		/* Bus error */

		bus->cmd_err = -EAGAIN;

		if (bus->master_or_slave == I2C_MASTER)

			complete(&bus->cmd_complete);



		do_complete = true;

		break;

	case I2C_WAKE_UP_IND:

		/* I2C wake up */
@@ -752,6 +747,8 @@ static void npcm_i2c_callback(struct npcm_i2c *bus, 
	if (bus->slave)

		bus->master_or_slave = I2C_SLAVE;

#endif

	if (do_complete)

		complete(&bus->cmd_complete);

}



static u8 npcm_i2c_fifo_usage(struct npcm_i2c *bus)