git: 11ba8488b863 - main - iicsmb: Request the bus recursively in bread()

[Allan Jude]

The branch main has been updated by allanjude:

URL: https://cgit.FreeBSD.org/src/commit/?id=11ba8488b8636a91668c0ee13d35d9e126dfba53

commit 11ba8488b8636a91668c0ee13d35d9e126dfba53
Author:     Allan Jude <allanjude at FreeBSD.org>
AuthorDate: 2021-02-23 20:06:16 +0000
Commit:     Allan Jude <allanjude at FreeBSD.org>
CommitDate: 2021-02-23 20:06:16 +0000

    iicsmb: Request the bus recursively in bread()
    
    ipmi_ssif will `smbus_request_bus()` to do multiple smbus requests
    (which requests the iicbus), and then here in `bread()` we also need to
    request the bus because `bread()` takes multiple transactions.
    This causes deadlock as it's waiting for the bus it already has without
    `IIC_RECURSIVE`.
    
    Sponsored by:   Ampere Computing LLC
    Submitted by:   Klara Inc.
    Reviewed by:    imp
    Differential Revision:  https://reviews.freebsd.org/D28742
---
 sys/dev/iicbus/iicsmb.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/sys/dev/iicbus/iicsmb.c b/sys/dev/iicbus/iicsmb.c
index 8e79452cf2a8..38e67c40d488 100644
--- a/sys/dev/iicbus/iicsmb.c
+++ b/sys/dev/iicbus/iicsmb.c
@@ -455,7 +455,7 @@ iicsmb_bread(device_t dev, u_char slave, char cmd, u_char *count, char *buf)
 	int error;
 
 	/* Have to do this because the command is split in two transfers. */
-	error = iicbus_request_bus(parent, dev, IIC_WAIT);
+	error = iicbus_request_bus(parent, dev, IIC_WAIT | IIC_RECURSIVE);
 	if (error == 0)
 		error = TRANSFER_MSGS(dev, msgs);
 	if (error == 0) {