linux: backport support for RTL8761b to 5.4

pkgs/os-specific/linux/kernel/patches.nix

@@ -76,6 +76,13 @@
     };
   };
 
+  # Adapted for Linux 5.4 from:
+  # https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?id=04896832c94aae4842100cafb8d3a73e1bed3a45
+  rtl8761b_support =
+    { name = "rtl8761b-support";
+      patch = ./rtl8761b-support.patch;
+    };
+
   export_kernel_fpu_functions = {
     "4.14" = {
       name = "export_kernel_fpu_functions";

pkgs/os-specific/linux/kernel/rtl8761b-support.patch

@@ -0,0 +1,33 @@
+diff --git a/drivers/bluetooth/btrtl.c b/drivers/bluetooth/btrtl.c
+index 67f4bc21e7c5..3a9afc905f24 100644
+--- a/drivers/bluetooth/btrtl.c
++++ b/drivers/bluetooth/btrtl.c
+@@ -130,12 +130,19 @@  static const struct id_table ic_id_table[] = {
+ 	  .cfg_name = "rtl_bt/rtl8821c_config" },
+
+ 	/* 8761A */
+-	{ IC_MATCH_FL_LMPSUBV, RTL_ROM_LMP_8761A, 0x0,
++	{ IC_INFO(RTL_ROM_LMP_8761A, 0xa),
+ 	  .config_needed = false,
+ 	  .has_rom_version = true,
+ 	  .fw_name  = "rtl_bt/rtl8761a_fw.bin",
+ 	  .cfg_name = "rtl_bt/rtl8761a_config" },
+
++	/* 8761B */
++	{ IC_INFO(RTL_ROM_LMP_8761A, 0xb),
++	  .config_needed = false,
++	  .has_rom_version = true,
++	  .fw_name  = "rtl_bt/rtl8761b_fw.bin",
++	  .cfg_name = "rtl_bt/rtl8761b_config" },
++
+	/* 8822C with USB interface */
+	{ IC_INFO(RTL_ROM_LMP_8822B, 0xc),
+	  .config_needed = false,
+@@ -251,6 +258,7 @@  static int rtlbt_parse_firmware(struct hci_dev *hdev,
+ 		{ RTL_ROM_LMP_8723B, 9 },	/* 8723D */
+ 		{ RTL_ROM_LMP_8821A, 10 },	/* 8821C */
+ 		{ RTL_ROM_LMP_8822B, 13 },	/* 8822C */
++		{ RTL_ROM_LMP_8761A, 14 },	/* 8761B */
+ 	};
+
+ 	min_size = sizeof(struct rtl_epatch_header) + sizeof(extension_sig) + 3;

pkgs/top-level/all-packages.nix

@@ -18378,6 +18378,7 @@ in
     kernelPatches = [
       kernelPatches.bridge_stp_helper
       kernelPatches.request_key_helper
+      kernelPatches.rtl8761b_support
       kernelPatches.export_kernel_fpu_functions."5.3"
     ];
   };