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 [[email protected]]

Signed-off-by: Anand Vastrad <[email protected]>
---
 .../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

-- 
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