diff --git a/include/mbedtls/aes.h b/include/mbedtls/aes.h
index 052f47c..25accb6 100644
--- a/include/mbedtls/aes.h
+++ b/include/mbedtls/aes.h
@@ -60,12 +60,6 @@
 /* Error codes in range 0x0021-0x0025 */
 #define MBEDTLS_ERR_AES_BAD_INPUT_DATA                    -0x0021  /**< Invalid input data. */
 
-/* MBEDTLS_ERR_AES_FEATURE_UNAVAILABLE is deprecated and should not be used. */
-#define MBEDTLS_ERR_AES_FEATURE_UNAVAILABLE               -0x0023  /**< Feature not available. For example, an unsupported AES key size. */
-
-/* MBEDTLS_ERR_AES_HW_ACCEL_FAILED is deprecated and should not be used. */
-#define MBEDTLS_ERR_AES_HW_ACCEL_FAILED                   -0x0025  /**< AES hardware accelerator failed. */
-
 #if ( defined(__ARMCC_VERSION) || defined(_MSC_VER) ) && \
     !defined(inline) && !defined(__cplusplus)
 #define inline __inline
diff --git a/include/mbedtls/arc4.h b/include/mbedtls/arc4.h
index 17728f4..ada6083 100644
--- a/include/mbedtls/arc4.h
+++ b/include/mbedtls/arc4.h
@@ -34,9 +34,6 @@
 
 #include <stddef.h>
 
-/* MBEDTLS_ERR_ARC4_HW_ACCEL_FAILED is deprecated and should not be used. */
-#define MBEDTLS_ERR_ARC4_HW_ACCEL_FAILED                  -0x0019  /**< ARC4 hardware accelerator failed. */
-
 #ifdef __cplusplus
 extern "C" {
 #endif
diff --git a/include/mbedtls/aria.h b/include/mbedtls/aria.h
index a4b27b3..7dd960f 100644
--- a/include/mbedtls/aria.h
+++ b/include/mbedtls/aria.h
@@ -47,20 +47,10 @@
 #define MBEDTLS_ARIA_MAX_ROUNDS  16 /**< Maxiumum number of rounds in ARIA. */
 #define MBEDTLS_ARIA_MAX_KEYSIZE 32 /**< Maximum size of an ARIA key in bytes. */
 
-#if !defined(MBEDTLS_DEPRECATED_REMOVED)
-#define MBEDTLS_ERR_ARIA_INVALID_KEY_LENGTH   MBEDTLS_DEPRECATED_NUMERIC_CONSTANT( -0x005C )
-#endif /* !MBEDTLS_DEPRECATED_REMOVED */
 #define MBEDTLS_ERR_ARIA_BAD_INPUT_DATA -0x005C /**< Bad input data. */
 
 #define MBEDTLS_ERR_ARIA_INVALID_INPUT_LENGTH -0x005E /**< Invalid data input length. */
 
-/* MBEDTLS_ERR_ARIA_FEATURE_UNAVAILABLE is deprecated and should not be used.
- */
-#define MBEDTLS_ERR_ARIA_FEATURE_UNAVAILABLE  -0x005A  /**< Feature not available. For example, an unsupported ARIA key size. */
-
-/* MBEDTLS_ERR_ARIA_HW_ACCEL_FAILED is deprecated and should not be used. */
-#define MBEDTLS_ERR_ARIA_HW_ACCEL_FAILED      -0x0058  /**< ARIA hardware accelerator failed. */
-
 #if !defined(MBEDTLS_ARIA_ALT)
 // Regular implementation
 //
diff --git a/include/mbedtls/blowfish.h b/include/mbedtls/blowfish.h
index c2a6ff9..1ade1fc 100644
--- a/include/mbedtls/blowfish.h
+++ b/include/mbedtls/blowfish.h
@@ -40,17 +40,10 @@
 #define MBEDTLS_BLOWFISH_ROUNDS      16         /**< Rounds to use. When increasing this value, make sure to extend the initialisation vectors */
 #define MBEDTLS_BLOWFISH_BLOCKSIZE   8          /* Blowfish uses 64 bit blocks */
 
-#if !defined(MBEDTLS_DEPRECATED_REMOVED)
-#define MBEDTLS_ERR_BLOWFISH_INVALID_KEY_LENGTH   MBEDTLS_DEPRECATED_NUMERIC_CONSTANT( -0x0016 )
-#endif /* !MBEDTLS_DEPRECATED_REMOVED */
 #define MBEDTLS_ERR_BLOWFISH_BAD_INPUT_DATA -0x0016 /**< Bad input data. */
 
 #define MBEDTLS_ERR_BLOWFISH_INVALID_INPUT_LENGTH -0x0018 /**< Invalid data input length. */
 
-/* MBEDTLS_ERR_BLOWFISH_HW_ACCEL_FAILED is deprecated and should not be used.
- */
-#define MBEDTLS_ERR_BLOWFISH_HW_ACCEL_FAILED                   -0x0017  /**< Blowfish hardware accelerator failed. */
-
 #ifdef __cplusplus
 extern "C" {
 #endif
diff --git a/include/mbedtls/camellia.h b/include/mbedtls/camellia.h
index f7d2b23..dee5c3e 100644
--- a/include/mbedtls/camellia.h
+++ b/include/mbedtls/camellia.h
@@ -36,17 +36,10 @@
 #define MBEDTLS_CAMELLIA_ENCRYPT     1
 #define MBEDTLS_CAMELLIA_DECRYPT     0
 
-#if !defined(MBEDTLS_DEPRECATED_REMOVED)
-#define MBEDTLS_ERR_CAMELLIA_INVALID_KEY_LENGTH   MBEDTLS_DEPRECATED_NUMERIC_CONSTANT( -0x0024 )
-#endif /* !MBEDTLS_DEPRECATED_REMOVED */
 #define MBEDTLS_ERR_CAMELLIA_BAD_INPUT_DATA -0x0024 /**< Bad input data. */
 
 #define MBEDTLS_ERR_CAMELLIA_INVALID_INPUT_LENGTH -0x0026 /**< Invalid data input length. */
 
-/* MBEDTLS_ERR_CAMELLIA_HW_ACCEL_FAILED is deprecated and should not be used.
- */
-#define MBEDTLS_ERR_CAMELLIA_HW_ACCEL_FAILED              -0x0027  /**< Camellia hardware accelerator failed. */
-
 #ifdef __cplusplus
 extern "C" {
 #endif
diff --git a/include/mbedtls/ccm.h b/include/mbedtls/ccm.h
index 7193863..f63e61b 100644
--- a/include/mbedtls/ccm.h
+++ b/include/mbedtls/ccm.h
@@ -58,9 +58,6 @@
 #define MBEDTLS_ERR_CCM_BAD_INPUT       -0x000D /**< Bad input parameters to the function. */
 #define MBEDTLS_ERR_CCM_AUTH_FAILED     -0x000F /**< Authenticated decryption failed. */
 
-/* MBEDTLS_ERR_CCM_HW_ACCEL_FAILED is deprecated and should not be used. */
-#define MBEDTLS_ERR_CCM_HW_ACCEL_FAILED -0x0011 /**< CCM hardware accelerator failed. */
-
 #ifdef __cplusplus
 extern "C" {
 #endif
diff --git a/include/mbedtls/chacha20.h b/include/mbedtls/chacha20.h
index e59dd1f..a6a8cda 100644
--- a/include/mbedtls/chacha20.h
+++ b/include/mbedtls/chacha20.h
@@ -43,14 +43,6 @@
 
 #define MBEDTLS_ERR_CHACHA20_BAD_INPUT_DATA         -0x0051 /**< Invalid input parameter(s). */
 
-/* MBEDTLS_ERR_CHACHA20_FEATURE_UNAVAILABLE is deprecated and should not be
- * used. */
-#define MBEDTLS_ERR_CHACHA20_FEATURE_UNAVAILABLE    -0x0053 /**< Feature not available. For example, s part of the API is not implemented. */
-
-/* MBEDTLS_ERR_CHACHA20_HW_ACCEL_FAILED is deprecated and should not be used.
- */
-#define MBEDTLS_ERR_CHACHA20_HW_ACCEL_FAILED        -0x0055  /**< Chacha20 hardware accelerator failed. */
-
 #ifdef __cplusplus
 extern "C" {
 #endif
diff --git a/include/mbedtls/cipher.h b/include/mbedtls/cipher.h
index 1cafa6e..ee9c8e6 100644
--- a/include/mbedtls/cipher.h
+++ b/include/mbedtls/cipher.h
@@ -62,6 +62,8 @@
 #define MBEDTLS_ERR_CIPHER_AUTH_FAILED          -0x6300  /**< Authentication failed (for AEAD modes). */
 #define MBEDTLS_ERR_CIPHER_INVALID_CONTEXT      -0x6380  /**< The context is invalid. For example, because it was freed. */
 
+// TODO [TR] for #4029: can't remove it because it's still used in the code.
+// see other TODOS
 /* MBEDTLS_ERR_CIPHER_HW_ACCEL_FAILED is deprecated and should not be used. */
 #define MBEDTLS_ERR_CIPHER_HW_ACCEL_FAILED      -0x6400  /**< Cipher hardware accelerator failed. */
 
diff --git a/include/mbedtls/cmac.h b/include/mbedtls/cmac.h
index cb538d0..702175f 100644
--- a/include/mbedtls/cmac.h
+++ b/include/mbedtls/cmac.h
@@ -38,9 +38,6 @@
 extern "C" {
 #endif
 
-/* MBEDTLS_ERR_CMAC_HW_ACCEL_FAILED is deprecated and should not be used. */
-#define MBEDTLS_ERR_CMAC_HW_ACCEL_FAILED -0x007A  /**< CMAC hardware accelerator failed. */
-
 #define MBEDTLS_AES_BLOCK_SIZE          16
 #define MBEDTLS_DES3_BLOCK_SIZE         8
 
diff --git a/include/mbedtls/compat-1.3.h b/include/mbedtls/compat-1.3.h
index 4017751..b89c3b0 100644
--- a/include/mbedtls/compat-1.3.h
+++ b/include/mbedtls/compat-1.3.h
@@ -1051,9 +1051,7 @@
 #define POLARSSL_ERR_BASE64_BUFFER_TOO_SMALL MBEDTLS_ERR_BASE64_BUFFER_TOO_SMALL
 #define POLARSSL_ERR_BASE64_INVALID_CHARACTER MBEDTLS_ERR_BASE64_INVALID_CHARACTER
 #define POLARSSL_ERR_BLOWFISH_INVALID_INPUT_LENGTH MBEDTLS_ERR_BLOWFISH_INVALID_INPUT_LENGTH
-#define POLARSSL_ERR_BLOWFISH_INVALID_KEY_LENGTH MBEDTLS_ERR_BLOWFISH_INVALID_KEY_LENGTH
 #define POLARSSL_ERR_CAMELLIA_INVALID_INPUT_LENGTH MBEDTLS_ERR_CAMELLIA_INVALID_INPUT_LENGTH
-#define POLARSSL_ERR_CAMELLIA_INVALID_KEY_LENGTH MBEDTLS_ERR_CAMELLIA_INVALID_KEY_LENGTH
 #define POLARSSL_ERR_CCM_AUTH_FAILED MBEDTLS_ERR_CCM_AUTH_FAILED
 #define POLARSSL_ERR_CCM_BAD_INPUT MBEDTLS_ERR_CCM_BAD_INPUT
 #define POLARSSL_ERR_CIPHER_ALLOC_FAILED MBEDTLS_ERR_CIPHER_ALLOC_FAILED
@@ -1206,7 +1204,6 @@
 #define POLARSSL_ERR_SSL_UNKNOWN_IDENTITY MBEDTLS_ERR_SSL_UNKNOWN_IDENTITY
 #define POLARSSL_ERR_SSL_WAITING_SERVER_HELLO_RENEGO MBEDTLS_ERR_SSL_WAITING_SERVER_HELLO_RENEGO
 #define POLARSSL_ERR_THREADING_BAD_INPUT_DATA MBEDTLS_ERR_THREADING_BAD_INPUT_DATA
-#define POLARSSL_ERR_THREADING_FEATURE_UNAVAILABLE MBEDTLS_ERR_THREADING_FEATURE_UNAVAILABLE
 #define POLARSSL_ERR_THREADING_MUTEX_ERROR MBEDTLS_ERR_THREADING_MUTEX_ERROR
 #define POLARSSL_ERR_X509_BAD_INPUT_DATA MBEDTLS_ERR_X509_BAD_INPUT_DATA
 #define POLARSSL_ERR_X509_CERT_UNKNOWN_FORMAT MBEDTLS_ERR_X509_CERT_UNKNOWN_FORMAT
diff --git a/include/mbedtls/des.h b/include/mbedtls/des.h
index 549d19b..92da73f 100644
--- a/include/mbedtls/des.h
+++ b/include/mbedtls/des.h
@@ -41,9 +41,6 @@
 
 #define MBEDTLS_ERR_DES_INVALID_INPUT_LENGTH              -0x0032  /**< The data input has an invalid length. */
 
-/* MBEDTLS_ERR_DES_HW_ACCEL_FAILED is deprecated and should not be used. */
-#define MBEDTLS_ERR_DES_HW_ACCEL_FAILED                   -0x0033  /**< DES hardware accelerator failed. */
-
 #define MBEDTLS_DES_KEY_SIZE    8
 
 #ifdef __cplusplus
diff --git a/include/mbedtls/dhm.h b/include/mbedtls/dhm.h
index c7830b9..0a259d1 100644
--- a/include/mbedtls/dhm.h
+++ b/include/mbedtls/dhm.h
@@ -82,10 +82,6 @@
 #define MBEDTLS_ERR_DHM_INVALID_FORMAT                    -0x3380  /**< The ASN.1 data is not formatted correctly. */
 #define MBEDTLS_ERR_DHM_ALLOC_FAILED                      -0x3400  /**< Allocation of memory failed. */
 #define MBEDTLS_ERR_DHM_FILE_IO_ERROR                     -0x3480  /**< Read or write of file failed. */
-
-/* MBEDTLS_ERR_DHM_HW_ACCEL_FAILED is deprecated and should not be used. */
-#define MBEDTLS_ERR_DHM_HW_ACCEL_FAILED                   -0x3500  /**< DHM hardware accelerator failed. */
-
 #define MBEDTLS_ERR_DHM_SET_GROUP_FAILED                  -0x3580  /**< Setting the modulus and generator failed. */
 
 #ifdef __cplusplus
diff --git a/include/mbedtls/ecp.h b/include/mbedtls/ecp.h
index 34dd0ea..149bda0 100644
--- a/include/mbedtls/ecp.h
+++ b/include/mbedtls/ecp.h
@@ -53,10 +53,6 @@
 #define MBEDTLS_ERR_ECP_RANDOM_FAILED                     -0x4D00  /**< Generation of random value, such as ephemeral key, failed. */
 #define MBEDTLS_ERR_ECP_INVALID_KEY                       -0x4C80  /**< Invalid private or public key. */
 #define MBEDTLS_ERR_ECP_SIG_LEN_MISMATCH                  -0x4C00  /**< The buffer contains a valid signature followed by more data. */
-
-/* MBEDTLS_ERR_ECP_HW_ACCEL_FAILED is deprecated and should not be used. */
-#define MBEDTLS_ERR_ECP_HW_ACCEL_FAILED                   -0x4B80  /**< The ECP hardware accelerator failed. */
-
 #define MBEDTLS_ERR_ECP_IN_PROGRESS                       -0x4B00  /**< Operation in progress, call again with the same parameters to continue. */
 
 /* Flags indicating whether to include code that is specific to certain
diff --git a/include/mbedtls/gcm.h b/include/mbedtls/gcm.h
index 6b67361..7636639 100644
--- a/include/mbedtls/gcm.h
+++ b/include/mbedtls/gcm.h
@@ -45,10 +45,6 @@
 #define MBEDTLS_GCM_DECRYPT     0
 
 #define MBEDTLS_ERR_GCM_AUTH_FAILED                       -0x0012  /**< Authenticated decryption failed. */
-
-/* MBEDTLS_ERR_GCM_HW_ACCEL_FAILED is deprecated and should not be used. */
-#define MBEDTLS_ERR_GCM_HW_ACCEL_FAILED                   -0x0013  /**< GCM hardware accelerator failed. */
-
 #define MBEDTLS_ERR_GCM_BAD_INPUT                         -0x0014  /**< Bad input parameters to function. */
 
 #ifdef __cplusplus
diff --git a/include/mbedtls/md.h b/include/mbedtls/md.h
index e4354ba..882ff74 100644
--- a/include/mbedtls/md.h
+++ b/include/mbedtls/md.h
@@ -38,6 +38,8 @@
 #define MBEDTLS_ERR_MD_ALLOC_FAILED                       -0x5180  /**< Failed to allocate memory. */
 #define MBEDTLS_ERR_MD_FILE_IO_ERROR                      -0x5200  /**< Opening or reading of file failed. */
 
+// TODO [TR] for #4029: can't remove it because it's still used in the code.
+// see other TODOs
 /* MBEDTLS_ERR_MD_HW_ACCEL_FAILED is deprecated and should not be used. */
 #define MBEDTLS_ERR_MD_HW_ACCEL_FAILED                    -0x5280  /**< MD hardware accelerator failed. */
 
diff --git a/include/mbedtls/md2.h b/include/mbedtls/md2.h
index 23c48f4..f82f8f8 100644
--- a/include/mbedtls/md2.h
+++ b/include/mbedtls/md2.h
@@ -35,9 +35,6 @@
 
 #include <stddef.h>
 
-/* MBEDTLS_ERR_MD2_HW_ACCEL_FAILED is deprecated and should not be used. */
-#define MBEDTLS_ERR_MD2_HW_ACCEL_FAILED                   -0x002B  /**< MD2 hardware accelerator failed */
-
 #ifdef __cplusplus
 extern "C" {
 #endif
diff --git a/include/mbedtls/md4.h b/include/mbedtls/md4.h
index eeb1670..a2e7e89 100644
--- a/include/mbedtls/md4.h
+++ b/include/mbedtls/md4.h
@@ -36,9 +36,6 @@
 #include <stddef.h>
 #include <stdint.h>
 
-/* MBEDTLS_ERR_MD4_HW_ACCEL_FAILED is deprecated and should not be used. */
-#define MBEDTLS_ERR_MD4_HW_ACCEL_FAILED                   -0x002D  /**< MD4 hardware accelerator failed */
-
 #ifdef __cplusplus
 extern "C" {
 #endif
diff --git a/include/mbedtls/md5.h b/include/mbedtls/md5.h
index aaca0f2..6b14f9e 100644
--- a/include/mbedtls/md5.h
+++ b/include/mbedtls/md5.h
@@ -35,9 +35,6 @@
 #include <stddef.h>
 #include <stdint.h>
 
-/* MBEDTLS_ERR_MD5_HW_ACCEL_FAILED is deprecated and should not be used. */
-#define MBEDTLS_ERR_MD5_HW_ACCEL_FAILED                   -0x002F  /**< MD5 hardware accelerator failed */
-
 #ifdef __cplusplus
 extern "C" {
 #endif
diff --git a/include/mbedtls/pk.h b/include/mbedtls/pk.h
index 7d0f977..f6ca04c 100644
--- a/include/mbedtls/pk.h
+++ b/include/mbedtls/pk.h
@@ -67,6 +67,8 @@
 #define MBEDTLS_ERR_PK_FEATURE_UNAVAILABLE -0x3980  /**< Unavailable feature, e.g. RSA disabled for RSA key. */
 #define MBEDTLS_ERR_PK_SIG_LEN_MISMATCH    -0x3900  /**< The buffer contains a valid signature followed by more data. */
 
+// TODO [TR] for #4029 can't remove it because it's still used in the code.
+// see the other TODOs
 /* MBEDTLS_ERR_PK_HW_ACCEL_FAILED is deprecated and should not be used. */
 #define MBEDTLS_ERR_PK_HW_ACCEL_FAILED     -0x3880  /**< PK hardware accelerator failed. */
 
diff --git a/include/mbedtls/poly1305.h b/include/mbedtls/poly1305.h
index 905c145..1767f58 100644
--- a/include/mbedtls/poly1305.h
+++ b/include/mbedtls/poly1305.h
@@ -43,14 +43,6 @@
 
 #define MBEDTLS_ERR_POLY1305_BAD_INPUT_DATA         -0x0057 /**< Invalid input parameter(s). */
 
-/* MBEDTLS_ERR_POLY1305_FEATURE_UNAVAILABLE is deprecated and should not be
- * used. */
-#define MBEDTLS_ERR_POLY1305_FEATURE_UNAVAILABLE    -0x0059 /**< Feature not available. For example, s part of the API is not implemented. */
-
-/* MBEDTLS_ERR_POLY1305_HW_ACCEL_FAILED is deprecated and should not be used.
- */
-#define MBEDTLS_ERR_POLY1305_HW_ACCEL_FAILED        -0x005B  /**< Poly1305 hardware accelerator failed. */
-
 #ifdef __cplusplus
 extern "C" {
 #endif
diff --git a/include/mbedtls/ripemd160.h b/include/mbedtls/ripemd160.h
index 381c725..a21a98c 100644
--- a/include/mbedtls/ripemd160.h
+++ b/include/mbedtls/ripemd160.h
@@ -31,10 +31,6 @@
 #include <stddef.h>
 #include <stdint.h>
 
-/* MBEDTLS_ERR_RIPEMD160_HW_ACCEL_FAILED is deprecated and should not be used.
- */
-#define MBEDTLS_ERR_RIPEMD160_HW_ACCEL_FAILED             -0x0031  /**< RIPEMD160 hardware accelerator failed */
-
 #ifdef __cplusplus
 extern "C" {
 #endif
diff --git a/include/mbedtls/rsa.h b/include/mbedtls/rsa.h
index 701fe8b..9ed5c81 100644
--- a/include/mbedtls/rsa.h
+++ b/include/mbedtls/rsa.h
@@ -58,9 +58,6 @@
  */
 #define MBEDTLS_ERR_RSA_UNSUPPORTED_OPERATION             -0x4500  /**< The implementation does not offer the requested operation, for example, because of security violations or lack of functionality. */
 
-/* MBEDTLS_ERR_RSA_HW_ACCEL_FAILED is deprecated and should not be used. */
-#define MBEDTLS_ERR_RSA_HW_ACCEL_FAILED                   -0x4580  /**< RSA hardware accelerator failed. */
-
 /*
  * RSA constants
  */
diff --git a/include/mbedtls/sha1.h b/include/mbedtls/sha1.h
index 86a3d06..d9db4c3 100644
--- a/include/mbedtls/sha1.h
+++ b/include/mbedtls/sha1.h
@@ -38,8 +38,6 @@
 #include <stddef.h>
 #include <stdint.h>
 
-/* MBEDTLS_ERR_SHA1_HW_ACCEL_FAILED is deprecated and should not be used. */
-#define MBEDTLS_ERR_SHA1_HW_ACCEL_FAILED                  -0x0035  /**< SHA-1 hardware accelerator failed */
 #define MBEDTLS_ERR_SHA1_BAD_INPUT_DATA                   -0x0073  /**< SHA-1 input data was malformed. */
 
 #ifdef __cplusplus
diff --git a/include/mbedtls/sha256.h b/include/mbedtls/sha256.h
index 73d9544..0c6f9dc 100644
--- a/include/mbedtls/sha256.h
+++ b/include/mbedtls/sha256.h
@@ -34,8 +34,6 @@
 #include <stddef.h>
 #include <stdint.h>
 
-/* MBEDTLS_ERR_SHA256_HW_ACCEL_FAILED is deprecated and should not be used. */
-#define MBEDTLS_ERR_SHA256_HW_ACCEL_FAILED                -0x0037  /**< SHA-256 hardware accelerator failed */
 #define MBEDTLS_ERR_SHA256_BAD_INPUT_DATA                 -0x0074  /**< SHA-256 input data was malformed. */
 
 #ifdef __cplusplus
diff --git a/include/mbedtls/sha512.h b/include/mbedtls/sha512.h
index 4a8ab42..3dce99a 100644
--- a/include/mbedtls/sha512.h
+++ b/include/mbedtls/sha512.h
@@ -33,8 +33,6 @@
 #include <stddef.h>
 #include <stdint.h>
 
-/* MBEDTLS_ERR_SHA512_HW_ACCEL_FAILED is deprecated and should not be used. */
-#define MBEDTLS_ERR_SHA512_HW_ACCEL_FAILED                -0x0039  /**< SHA-512 hardware accelerator failed */
 #define MBEDTLS_ERR_SHA512_BAD_INPUT_DATA                 -0x0075  /**< SHA-512 input data was malformed. */
 
 #ifdef __cplusplus
diff --git a/include/mbedtls/threading.h b/include/mbedtls/threading.h
index 05e27c5..1047f8f 100644
--- a/include/mbedtls/threading.h
+++ b/include/mbedtls/threading.h
@@ -34,10 +34,6 @@
 extern "C" {
 #endif
 
-/* MBEDTLS_ERR_THREADING_FEATURE_UNAVAILABLE is deprecated and should not be
- * used. */
-#define MBEDTLS_ERR_THREADING_FEATURE_UNAVAILABLE         -0x001A  /**< The selected feature is not available. */
-
 #define MBEDTLS_ERR_THREADING_BAD_INPUT_DATA              -0x001C  /**< Bad input parameters to function. */
 #define MBEDTLS_ERR_THREADING_MUTEX_ERROR                 -0x001E  /**< Locking / unlocking / free failed with error code. */
 
diff --git a/include/mbedtls/xtea.h b/include/mbedtls/xtea.h
index 473dd4b..5ce2fe4 100644
--- a/include/mbedtls/xtea.h
+++ b/include/mbedtls/xtea.h
@@ -36,9 +36,6 @@
 
 #define MBEDTLS_ERR_XTEA_INVALID_INPUT_LENGTH             -0x0028  /**< The data input has an invalid length. */
 
-/* MBEDTLS_ERR_XTEA_HW_ACCEL_FAILED is deprecated and should not be used. */
-#define MBEDTLS_ERR_XTEA_HW_ACCEL_FAILED                  -0x0029  /**< XTEA hardware accelerator failed. */
-
 #ifdef __cplusplus
 extern "C" {
 #endif