[meta-intel] [meta-intel LMS][PATCHV2 1/2] Fix device file referance to /dev/mei0 and remove select post write.

[Anand Vastrad]

LMS uses /dev/mei character device which is absent on current kernel versions causing LMS fail to initialize. LMS sends messages to MEI with a post select timeout. Select timeout causes SendMessage to fail causing LMS to not to communicate properly with MEI.

Adding /dev/mei0 device file reference to check first and then /dev/mei sucessfully initializes LMS. Rely on write return length and remove select with timeout to fix communication with MEI.

Upstream-Status: Submitted [meta-intel at yoctoproject.org]

Signed-off-by: Anand Vastrad <anand.vastrad at intel.com>
---
 .../amt/lms/0003-device-file-reference-fix.patch   | 73 ++++++++++++++++++++++
 1 file changed, 73 insertions(+)
 create mode 100644 common/recipes-bsp/amt/lms/0003-device-file-reference-fix.patch

diff --git a/common/recipes-bsp/amt/lms/0003-device-file-reference-fix.patch b/common/recipes-bsp/amt/lms/0003-device-file-reference-fix.patch
new file mode 100644
index 0000000..0269438
--- /dev/null
+++ b/common/recipes-bsp/amt/lms/0003-device-file-reference-fix.patch
@@ -0,0 +1,73 @@
+--- lms8_8.0.0-7.orig/src/mei/MEILinux.cpp	2012-10-11 05:16:05.000000000 -0700
++++ lms8_8.0.0-7/src/mei/MEILinux.cpp	2017-06-21 15:14:13.725853901 -0700
+@@ -94,13 +94,17 @@
+		Deinit();
+	}
+
+-	_fd = open("/dev/mei", O_RDWR);
++	_fd = open("/dev/mei0", O_RDWR);
+
+	if (_fd == -1 ) {
+		if (_verbose) {
+-			fprintf(stderr, "Error: Cannot establish a handle to the MEI driver\n");
++			fprintf(stderr, "Warning: Cannot establish a handle to the MEI driver mei0, retrying with mei \n");
++		}
++		_fd = open("/dev/mei", O_RDWR);
++		if (_fd == -1 ) {
++			fprintf(stderr, "Error: Cannot establish a handle to the MEI driver mei\n");
++			return false;
+		}
+-		return false;
+	}
+	_initialized = true;
+
+@@ -181,13 +185,7 @@
+ int MEILinux::SendMessage(const unsigned char *buffer, int len, unsigned long timeout)
+ {
+	int rv = 0;
+-	int return_length =0;
+	int error = 0;
+-	fd_set set;
+-	struct timeval tv;
+-
+-	tv.tv_sec =  timeout / 1000;
+-	tv.tv_usec =(timeout % 1000) * 1000000;
+
+	if (_verbose) {
+		fprintf(stdout, "call write length = %d\n", len);
+@@ -198,35 +196,8 @@
+		if (_verbose) {
+			fprintf(stderr,"write failed with status %d %d\n", rv, error);
+		}
+-		goto out;
+-	}
+-
+-	return_length = rv;
+-
+-	FD_ZERO(&set);
+-	FD_SET(_fd, &set);
+-	rv = select(_fd+1 ,&set, NULL, NULL, &tv);
+-	if (rv > 0 && FD_ISSET(_fd, &set)) {
+-		if (_verbose) {
+-			fprintf(stderr, "write success\n");
+-		}
+	}
+-	else if (rv == 0) {
+-		if (_verbose) {
+-			fprintf(stderr, "write failed on timeout with status\n");
+-		}
+-		goto out;
+-	}
+-	else { //rv<0
+-		if (_verbose) {
+-			fprintf(stderr, "write failed on select with status %d\n", rv);
+-		}
+-		goto out;
+-	}
+-
+-	rv = return_length;
+
+-out:
+	if (rv < 0) {
+		Deinit();
+	}
-- 
2.7.4