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authorYazen Ghannam <yazen.ghannam@amd.com>2026-09-03 10:43:25 -0500
committerBorislav Petkov (AMD) <bp@alien8.de>2026-09-10 18:05:43 -0700
commit27600805e62f800bacf990354632eae4e487d34c (patch)
treee8aec0ddfaa0bc264d79af632e3de3f1b75ae4c8 /Documentation/admin-guide/lcd-panel-cgram.rst
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x86/amd_node: Fix PCI device reference counting in amd_smn_init()grafted
The local "root" pointer is a temporary variable used during the device search. Therefore, refcount related to the search iterators should be cleaned up after the search is complete. Use the __free() cleanup macro to ensure the refcount is decremented when the temporary pointer goes out of scope. Additionally, increment the refcount when caching a root pointer. This ensures the in-use refcount is separate from the temporary search refcounting. Finally, drop the redundant "root = NULL" before the second search loop. The pci_get_class() iterator always decrements the refcount of its "from" argument, so the first loop can only fall through with "root" already NULL. Fixes: 0a4b61d9c2e4 ("x86/amd_node: Fix AMD root device caching") Closes: https://sashiko.dev/#/patchset/20260806160159.230453-1-jason.andryuk%40amd.com Reported-by: Sashiko <sashiko-bot@kernel.org> Assisted-by: LLM Signed-off-by: Yazen Ghannam <yazen.ghannam@amd.com> Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de> Reviewed-by: Mario Limonciello (AMD) <superm1@kernel.org> Cc: <stable@kernel.org> Link: https://patch.msgid.link/20260903154325.74343-1-yazen.ghannam@amd.com
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+======================================
+Parallel port LCD/Keypad Panel support
+======================================
+
+Some LCDs allow you to define up to 8 characters, mapped to ASCII
+characters 0 to 7. The escape code to define a new character is
+'\e[LG' followed by one digit from 0 to 7, representing the character
+number, and up to 8 couples of hex digits terminated by a semi-colon
+(';'). Each couple of digits represents a line, with 1-bits for each
+illuminated pixel with LSB on the right. Lines are numbered from the
+top of the character to the bottom. On a 5x7 matrix, only the 5 lower
+bits of the 7 first bytes are used for each character. If the string
+is incomplete, only complete lines will be redefined. Here are some
+examples::
+
+ printf "\e[LG0010101050D1F0C04;" => 0 = [enter]
+ printf "\e[LG1040E1F0000000000;" => 1 = [up]
+ printf "\e[LG2000000001F0E0400;" => 2 = [down]
+ printf "\e[LG3040E1F001F0E0400;" => 3 = [up-down]
+ printf "\e[LG40002060E1E0E0602;" => 4 = [left]
+ printf "\e[LG500080C0E0F0E0C08;" => 5 = [right]
+ printf "\e[LG60016051516141400;" => 6 = "IP"
+
+ printf "\e[LG00103071F1F070301;" => big speaker
+ printf "\e[LG00002061E1E060200;" => small speaker
+
+Willy