Merge tag 'tpmdd-next-v5.17-fixed' of git://git.kernel.org/pub/scm/linux/kernel/git/jarkko/linux-tpmdd

dabd40ec · Linus Torvalds <[email protected]> · 2022-01-11 12:58:41 -08:00

Pull TPM updates from Jarkko Sakkinen:
 "Other than bug fixes for TPM, this includes a patch for asymmetric
  keys to allow to look up and verify with self-signed certificates
  (keys without so called AKID - Authority Key Identifier) using a new
  "dn:" prefix in the query"

* tag 'tpmdd-next-v5.17-fixed' of git://git.kernel.org/pub/scm/linux/kernel/git/jarkko/linux-tpmdd:
  lib: remove redundant assignment to variable ret
  tpm: fix NPE on probe for missing device
  tpm: fix potential NULL pointer access in tpm_del_char_device
  tpm: Add Upgrade/Reduced mode support for TPM2 modules
  char: tpm: cr50: Set TPM_FIRMWARE_POWER_MANAGED based on device property
  keys: X.509 public key issuer lookup without AKID
  tpm_tis: Fix an error handling path in 'tpm_tis_core_init()'
  tpm: tpm_tis_spi_cr50: Add default RNG quality
  tpm/st33zp24: drop unneeded over-commenting
  tpm: add request_locality before write TPM_INT_ENABLE

Commit: dabd40ecaf693a18afd4c59c8d7280610d95b66e
Parents: 4aa1b825 · d99a8af4

Merge commit. Changes below are compared with the first parent: 4aa1b825.

Changes

16 files changed · +205 −161

File	Status	Add	Del	Content
crypto/asymmetric_keys/asymmetric_type.c	modified	+44	−13	View file
crypto/asymmetric_keys/pkcs7_trust.c	modified	+3	−3	View file
crypto/asymmetric_keys/restrict.c	modified	+29	−19	View file
crypto/asymmetric_keys/x509_cert_parser.c	modified	+10	−0	View file
crypto/asymmetric_keys/x509_public_key.c	modified	+10	−0	View file
drivers/char/tpm/st33zp24/st33zp24.c	modified	+17	−105	View file
drivers/char/tpm/tpm-chip.c	modified	+25	−12	View file
drivers/char/tpm/tpm-sysfs.c	modified	+3	−0	View file
drivers/char/tpm/tpm2-cmd.c	modified	+6	−0	View file
drivers/char/tpm/tpm_tis_core.c	modified	+11	−3	View file
drivers/char/tpm/tpm_tis_i2c_cr50.c	modified	+15	−1	View file
drivers/char/tpm/tpm_tis_spi_cr50.c	modified	+19	−1	View file
include/crypto/public_key.h	modified	+1	−1	View file
include/keys/asymmetric-type.h	modified	+2	−1	View file
include/linux/tpm.h	modified	+10	−0	View file
lib/asn1_encoder.c	modified	+0	−2	View file

Only the first 600 diff lines are shown. Download the complete patch.

crypto/asymmetric_keys/asymmetric_type.c

View file

diff --git a/crypto/asymmetric_keys/asymmetric_type.c b/crypto/asymmetric_keys/asymmetric_type.c
index ad8af3d..41a2f0e 100644
--- a/crypto/asymmetric_keys/asymmetric_type.c
+++ b/crypto/asymmetric_keys/asymmetric_type.c
@@ -36,16 +36,23 @@ static DECLARE_RWSEM(asymmetric_key_parsers_sem);
  * find_asymmetric_key - Find a key by ID.
  * @keyring: The keys to search.
  * @id_0: The first ID to look for or NULL.
- * @id_1: The second ID to look for or NULL.
- * @partial: Use partial match if true, exact if false.
+ * @id_1: The second ID to look for or NULL, matched together with @id_0
+ * against @keyring keys' id[0] and id[1].
+ * @id_2: The fallback ID to match against @keyring keys' id[2] if both of the
+ * other IDs are NULL.
+ * @partial: Use partial match for @id_0 and @id_1 if true, exact if false.
  *
  * Find a key in the given keyring by identifier.  The preferred identifier is
  * the id_0 and the fallback identifier is the id_1.  If both are given, the
- * lookup is by the former, but the latter must also match.
+ * former is matched (exactly or partially) against either of the sought key's
+ * identifiers and the latter must match the found key's second identifier
+ * exactly.  If both are missing, id_2 must match the sought key's third
+ * identifier exactly.
  */
 struct key *find_asymmetric_key(struct key *keyring,
 				const struct asymmetric_key_id *id_0,
 				const struct asymmetric_key_id *id_1,
+				const struct asymmetric_key_id *id_2,
 				bool partial)
 {
 	struct key *key;
@@ -54,14 +61,17 @@ struct key *find_asymmetric_key(struct key *keyring,
 	char *req, *p;
 	int len;
 
-	BUG_ON(!id_0 && !id_1);
+	WARN_ON(!id_0 && !id_1 && !id_2);
 
 	if (id_0) {
 		lookup = id_0->data;
 		len = id_0->len;
-	} else {
+	} else if (id_1) {
 		lookup = id_1->data;
 		len = id_1->len;
+	} else {
+		lookup = id_2->data;
+		len = id_2->len;
 	}
 
 	/* Construct an identifier "id:<keyid>". */
@@ -69,7 +79,10 @@ struct key *find_asymmetric_key(struct key *keyring,
 	if (!req)
 		return ERR_PTR(-ENOMEM);
 
-	if (partial) {
+	if (!id_0 && !id_1) {
+		*p++ = 'd';
+		*p++ = 'n';
+	} else if (partial) {
 		*p++ = 'i';
 		*p++ = 'd';
 	} else {
@@ -185,8 +198,8 @@ bool asymmetric_key_id_partial(const struct asymmetric_key_id *kid1,
 EXPORT_SYMBOL_GPL(asymmetric_key_id_partial);
 
 /**
- * asymmetric_match_key_ids - Search asymmetric key IDs
- * @kids: The list of key IDs to check
+ * asymmetric_match_key_ids - Search asymmetric key IDs 1 & 2
+ * @kids: The pair of key IDs to check
  * @match_id: The key ID we're looking for
  * @match: The match function to use
  */
@@ -200,7 +213,7 @@ static bool asymmetric_match_key_ids(
 
 	if (!kids || !match_id)
 		return false;
-	for (i = 0; i < ARRAY_SIZE(kids->id); i++)
+	for (i = 0; i < 2; i++)
 		if (match(kids->id[i], match_id))
 			return true;
 	return false;
@@ -244,7 +257,7 @@ struct asymmetric_key_id *asymmetric_key_hex_to_key_id(const char *id)
 }
 
 /*
- * Match asymmetric keys by an exact match on an ID.
+ * Match asymmetric keys by an exact match on one of the first two IDs.
  */
 static bool asymmetric_key_cmp(const struct key *key,
 			       const struct key_match_data *match_data)
@@ -257,7 +270,7 @@ static bool asymmetric_key_cmp(const struct key *key,
 }
 
 /*
- * Match asymmetric keys by a partial match on an IDs.
+ * Match asymmetric keys by a partial match on one of the first two IDs.
  */
 static bool asymmetric_key_cmp_partial(const struct key *key,
 				       const struct key_match_data *match_data)
@@ -270,14 +283,27 @@ static bool asymmetric_key_cmp_partial(const struct key *key,
 }
 
 /*
+ * Match asymmetric keys by an exact match on the third IDs.
+ */
+static bool asymmetric_key_cmp_name(const struct key *key,
+				    const struct key_match_data *match_data)
+{
+	const struct asymmetric_key_ids *kids = asymmetric_key_ids(key);
+	const struct asymmetric_key_id *match_id = match_data->preparsed;
+
+	return kids && asymmetric_key_id_same(kids->id[2], match_id);
+}
+
+/*
  * Preparse the match criterion.  If we don't set lookup_type and cmp,
  * the default will be an exact match on the key description.
  *
  * There are some specifiers for matching key IDs rather than by the key
  * description:
  *
- *	"id:<id>" - find a key by partial match on any available ID
- *	"ex:<id>" - find a key by exact match on any available ID
+ *	"id:<id>" - find a key by partial match on one of the first two IDs
+ *	"ex:<id>" - find a key by exact match on one of the first two IDs
+ *	"dn:<id>" - find a key by exact match on the third ID
  *
  * These have to be searched by iteration rather than by direct lookup because
  * the key is hashed according to its description.
@@ -301,6 +327,11 @@ static int asymmetric_key_match_preparse(struct key_match_data *match_data)
 		   spec[1] == 'x' &&
 		   spec[2] == ':') {
 		id = spec + 3;
+	} else if (spec[0] == 'd' &&
+		   spec[1] == 'n' &&
+		   spec[2] == ':') {
+		id = spec + 3;
+		cmp = asymmetric_key_cmp_name;
 	} else {
 		goto default_match;
 	}

crypto/asymmetric_keys/pkcs7_trust.c

View file

diff --git a/crypto/asymmetric_keys/pkcs7_trust.c b/crypto/asymmetric_keys/pkcs7_trust.c
index b531df2..9a87c34 100644
--- a/crypto/asymmetric_keys/pkcs7_trust.c
+++ b/crypto/asymmetric_keys/pkcs7_trust.c
@@ -48,7 +48,7 @@ static int pkcs7_validate_trust_one(struct pkcs7_message *pkcs7,
 		 * keys.
 		 */
 		key = find_asymmetric_key(trust_keyring,
-					  x509->id, x509->skid, false);
+					  x509->id, x509->skid, NULL, false);
 		if (!IS_ERR(key)) {
 			/* One of the X.509 certificates in the PKCS#7 message
 			 * is apparently the same as one we already trust.
@@ -82,7 +82,7 @@ static int pkcs7_validate_trust_one(struct pkcs7_message *pkcs7,
 		key = find_asymmetric_key(trust_keyring,
 					  last->sig->auth_ids[0],
 					  last->sig->auth_ids[1],
-					  false);
+					  NULL, false);
 		if (!IS_ERR(key)) {
 			x509 = last;
 			pr_devel("sinfo %u: Root cert %u signer is key %x\n",
@@ -97,7 +97,7 @@ static int pkcs7_validate_trust_one(struct pkcs7_message *pkcs7,
 	 * the signed info directly.
 	 */
 	key = find_asymmetric_key(trust_keyring,
-				  sinfo->sig->auth_ids[0], NULL, false);
+				  sinfo->sig->auth_ids[0], NULL, NULL, false);
 	if (!IS_ERR(key)) {
 		pr_devel("sinfo %u: Direct signer is key %x\n",
 			 sinfo->index, key_serial(key));

crypto/asymmetric_keys/restrict.c

View file

diff --git a/crypto/asymmetric_keys/restrict.c b/crypto/asymmetric_keys/restrict.c
index 84cefe3..6b1ac5f 100644
--- a/crypto/asymmetric_keys/restrict.c
+++ b/crypto/asymmetric_keys/restrict.c
@@ -87,7 +87,7 @@ int restrict_link_by_signature(struct key *dest_keyring,
 	sig = payload->data[asym_auth];
 	if (!sig)
 		return -ENOPKG;
-	if (!sig->auth_ids[0] && !sig->auth_ids[1])
+	if (!sig->auth_ids[0] && !sig->auth_ids[1] && !sig->auth_ids[2])
 		return -ENOKEY;
 
 	if (ca_keyid && !asymmetric_key_id_partial(sig->auth_ids[1], ca_keyid))
@@ -96,7 +96,7 @@ int restrict_link_by_signature(struct key *dest_keyring,
 	/* See if we have a key that signed this one. */
 	key = find_asymmetric_key(trust_keyring,
 				  sig->auth_ids[0], sig->auth_ids[1],
-				  false);
+				  sig->auth_ids[2], false);
 	if (IS_ERR(key))
 		return -ENOKEY;
 
@@ -108,11 +108,11 @@ int restrict_link_by_signature(struct key *dest_keyring,
 	return ret;
 }
 
-static bool match_either_id(const struct asymmetric_key_ids *pair,
+static bool match_either_id(const struct asymmetric_key_id **pair,
 			    const struct asymmetric_key_id *single)
 {
-	return (asymmetric_key_id_same(pair->id[0], single) ||
-		asymmetric_key_id_same(pair->id[1], single));
+	return (asymmetric_key_id_same(pair[0], single) ||
+		asymmetric_key_id_same(pair[1], single));
 }
 
 static int key_or_keyring_common(struct key *dest_keyring,
@@ -140,20 +140,22 @@ static int key_or_keyring_common(struct key *dest_keyring,
 	sig = payload->data[asym_auth];
 	if (!sig)
 		return -ENOPKG;
-	if (!sig->auth_ids[0] && !sig->auth_ids[1])
+	if (!sig->auth_ids[0] && !sig->auth_ids[1] && !sig->auth_ids[2])
 		return -ENOKEY;
 
 	if (trusted) {
 		if (trusted->type == &key_type_keyring) {
 			/* See if we have a key that signed this one. */
 			key = find_asymmetric_key(trusted, sig->auth_ids[0],
-						  sig->auth_ids[1], false);
+						  sig->auth_ids[1],
+						  sig->auth_ids[2], false);
 			if (IS_ERR(key))
 				key = NULL;
 		} else if (trusted->type == &key_type_asymmetric) {
-			const struct asymmetric_key_ids *signer_ids;
+			const struct asymmetric_key_id **signer_ids;
 
-			signer_ids = asymmetric_key_ids(trusted);
+			signer_ids = (const struct asymmetric_key_id **)
+				asymmetric_key_ids(trusted)->id;
 
 			/*
 			 * The auth_ids come from the candidate key (the
@@ -164,22 +166,29 @@ static int key_or_keyring_common(struct key *dest_keyring,
 			 * The signer_ids are identifiers for the
 			 * signing key specified for dest_keyring.
 			 *
-			 * The first auth_id is the preferred id, and
-			 * the second is the fallback. If only one
-			 * auth_id is present, it may match against
-			 * either signer_id. If two auth_ids are
-			 * present, the first auth_id must match one
-			 * signer_id and the second auth_id must match
-			 * the second signer_id.
+			 * The first auth_id is the preferred id, 2nd and
+			 * 3rd are the fallbacks. If exactly one of
+			 * auth_ids[0] and auth_ids[1] is present, it may
+			 * match either signer_ids[0] or signed_ids[1].
+			 * If both are present the first one may match
+			 * either signed_id but the second one must match
+			 * the second signer_id. If neither of them is
+			 * available, auth_ids[2] is matched against
+			 * signer_ids[2] as a fallback.
 			 */
-			if (!sig->auth_ids[0] || !sig->auth_ids[1]) {
+			if (!sig->auth_ids[0] && !sig->auth_ids[1]) {
+				if (asymmetric_key_id_same(signer_ids[2],
+							   sig->auth_ids[2]))
+					key = __key_get(trusted);
+
+			} else if (!sig->auth_ids[0] || !sig->auth_ids[1]) {
 				const struct asymmetric_key_id *auth_id;
 
 				auth_id = sig->auth_ids[0] ?: sig->auth_ids[1];
 				if (match_either_id(signer_ids, auth_id))
 					key = __key_get(trusted);
 
-			} else if (asymmetric_key_id_same(signer_ids->id[1],
+			} else if (asymmetric_key_id_same(signer_ids[1],
 							  sig->auth_ids[1]) &&
 				   match_either_id(signer_ids,
 						   sig->auth_ids[0])) {
@@ -193,7 +202,8 @@ static int key_or_keyring_common(struct key *dest_keyring,
 	if (check_dest && !key) {
 		/* See if the destination has a key that signed this one. */
 		key = find_asymmetric_key(dest_keyring, sig->auth_ids[0],
-					  sig->auth_ids[1], false);
+					  sig->auth_ids[1], sig->auth_ids[2],
+					  false);
 		if (IS_ERR(key))
 			key = NULL;
 	}

crypto/asymmetric_keys/x509_cert_parser.c

View file

diff --git a/crypto/asymmetric_keys/x509_cert_parser.c b/crypto/asymmetric_keys/x509_cert_parser.c
index 6d00309..083405e 100644
--- a/crypto/asymmetric_keys/x509_cert_parser.c
+++ b/crypto/asymmetric_keys/x509_cert_parser.c
@@ -441,8 +441,18 @@ int x509_note_issuer(void *context, size_t hdrlen,
 		     const void *value, size_t vlen)
 {
 	struct x509_parse_context *ctx = context;
+	struct asymmetric_key_id *kid;
+
 	ctx->cert->raw_issuer = value;
 	ctx->cert->raw_issuer_size = vlen;
+
+	if (!ctx->cert->sig->auth_ids[2]) {
+		kid = asymmetric_key_generate_id(value, vlen, "", 0);
+		if (IS_ERR(kid))
+			return PTR_ERR(kid);
+		ctx->cert->sig->auth_ids[2] = kid;
+	}
+
 	return x509_fabricate_name(ctx, hdrlen, tag, &ctx->cert->issuer, vlen);
 }
 

crypto/asymmetric_keys/x509_public_key.c

View file

diff --git a/crypto/asymmetric_keys/x509_public_key.c b/crypto/asymmetric_keys/x509_public_key.c
index 3d45161..fe14cae 100644
--- a/crypto/asymmetric_keys/x509_public_key.c
+++ b/crypto/asymmetric_keys/x509_public_key.c
@@ -223,6 +223,13 @@ static int x509_key_preparse(struct key_preparsed_payload *prep)
 		goto error_free_desc;
 	kids->id[0] = cert->id;
 	kids->id[1] = cert->skid;
+	kids->id[2] = asymmetric_key_generate_id(cert->raw_subject,
+						 cert->raw_subject_size,
+						 "", 0);
+	if (IS_ERR(kids->id[2])) {
+		ret = PTR_ERR(kids->id[2]);
+		goto error_free_kids;
+	}
 
 	/* We're pinning the module by being linked against it */
 	__module_get(public_key_subtype.owner);
@@ -239,8 +246,11 @@ static int x509_key_preparse(struct key_preparsed_payload *prep)
 	cert->skid = NULL;
 	cert->sig = NULL;
 	desc = NULL;
+	kids = NULL;
 	ret = 0;
 
+error_free_kids:
+	kfree(kids);
 error_free_desc:
 	kfree(desc);
 error_free_cert:

drivers/char/tpm/st33zp24/st33zp24.c

View file

diff --git a/drivers/char/tpm/st33zp24/st33zp24.c b/drivers/char/tpm/st33zp24/st33zp24.c
index 4ec10ab..ce9efb7 100644
--- a/drivers/char/tpm/st33zp24/st33zp24.c
+++ b/drivers/char/tpm/st33zp24/st33zp24.c
@@ -61,9 +61,7 @@ enum tis_defaults {
 };
 
 /*
- * clear_interruption clear the pending interrupt.
- * @param: tpm_dev, the tpm device device.
- * @return: the interrupt status value.
+ * clear the pending interrupt.
  */
 static u8 clear_interruption(struct st33zp24_dev *tpm_dev)
 {
@@ -72,12 +70,10 @@ static u8 clear_interruption(struct st33zp24_dev *tpm_dev)
 	tpm_dev->ops->recv(tpm_dev->phy_id, TPM_INT_STATUS, &interrupt, 1);
 	tpm_dev->ops->send(tpm_dev->phy_id, TPM_INT_STATUS, &interrupt, 1);
 	return interrupt;
-} /* clear_interruption() */
+}
 
 /*
- * st33zp24_cancel, cancel the current command execution or
- * set STS to COMMAND READY.
- * @param: chip, the tpm_chip description as specified in driver/char/tpm/tpm.h
+ * cancel the current command execution or set STS to COMMAND READY.
  */
 static void st33zp24_cancel(struct tpm_chip *chip)
 {
@@ -86,12 +82,10 @@ static void st33zp24_cancel(struct tpm_chip *chip)
 
 	data = TPM_STS_COMMAND_READY;
 	tpm_dev->ops->send(tpm_dev->phy_id, TPM_STS, &data, 1);
-} /* st33zp24_cancel() */
+}
 
 /*
- * st33zp24_status return the TPM_STS register
- * @param: chip, the tpm chip description
- * @return: the TPM_STS register value.
+ * return the TPM_STS register
  */
 static u8 st33zp24_status(struct tpm_chip *chip)
 {
@@ -100,12 +94,10 @@ static u8 st33zp24_status(struct tpm_chip *chip)
 
 	tpm_dev->ops->recv(tpm_dev->phy_id, TPM_STS, &data, 1);
 	return data;
-} /* st33zp24_status() */
+}
 
 /*
- * check_locality if the locality is active
- * @param: chip, the tpm chip description
- * @return: true if LOCALITY0 is active, otherwise false
+ * if the locality is active
  */
 static bool check_locality(struct tpm_chip *chip)
 {
@@ -120,13 +112,8 @@ static bool check_locality(struct tpm_chip *chip)
 		return true;
 
 	return false;
-} /* check_locality() */
+}
 
-/*
- * request_locality request the TPM locality
- * @param: chip, the chip description
- * @return: the active locality or negative value.
- */
 static int request_locality(struct tpm_chip *chip)
 {
 	struct st33zp24_dev *tpm_dev = dev_get_drvdata(&chip->dev);
@@ -153,12 +140,8 @@ static int request_locality(struct tpm_chip *chip)
 
 	/* could not get locality */
 	return -EACCES;
-} /* request_locality() */
+}
 
-/*
- * release_locality release the active locality
- * @param: chip, the tpm chip description.
- */
 static void release_locality(struct tpm_chip *chip)
 {
 	struct st33zp24_dev *tpm_dev = dev_get_drvdata(&chip->dev);
@@ -171,8 +154,6 @@ static void release_locality(struct tpm_chip *chip)
 
 /*
  * get_burstcount return the burstcount value
- * @param: chip, the chip description
- * return: the burstcount or negative value.
  */
 static int get_burstcount(struct tpm_chip *chip)
 {
@@ -200,18 +181,8 @@ static int get_burstcount(struct tpm_chip *chip)
 		msleep(TPM_TIMEOUT);
 	} while (time_before(jiffies, stop));
 	return -EBUSY;
-} /* get_burstcount() */
-
+}
 
-/*
- * wait_for_tpm_stat_cond
- * @param: chip, chip description
- * @param: mask, expected mask value
- * @param: check_cancel, does the command expected to be canceled ?
- * @param: canceled, did we received a cancel request ?
- * @return: true if status == mask or if the command is canceled.
- * false in other cases.
- */
 static bool wait_for_tpm_stat_cond(struct tpm_chip *chip, u8 mask,
 				bool check_cancel, bool *canceled)
 {
@@ -228,13 +199,7 @@ static bool wait_for_tpm_stat_cond(struct tpm_chip *chip, u8 mask,
 }
 
 /*
- * wait_for_stat wait for a TPM_STS value
- * @param: chip, the tpm chip description
- * @param: mask, the value mask to wait
- * @param: timeout, the timeout
- * @param: queue, the wait queue.
- * @param: check_cancel, does the command can be cancelled ?
- * @return: the tpm status, 0 if success, -ETIME if timeout is reached.
+ * wait for a TPM_STS value
  */
 static int wait_for_stat(struct tpm_chip *chip, u8 mask, unsigned long timeout,
 			wait_queue_head_t *queue, bool check_cancel)
@@ -292,15 +257,8 @@ static int wait_for_stat(struct tpm_chip *chip, u8 mask, unsigned long timeout,
 	}
 
 	return -ETIME;
-} /* wait_for_stat() */
+}
 
-/*
- * recv_data receive data
- * @param: chip, the tpm chip description
- * @param: buf, the buffer where the data are received
- * @param: count, the number of data to receive
- * @return: the number of bytes read from TPM FIFO.
- */
 static int recv_data(struct tpm_chip *chip, u8 *buf, size_t count)
 {
 	struct st33zp24_dev *tpm_dev = dev_get_drvdata(&chip->dev);
@@ -325,12 +283,6 @@ static int recv_data(struct tpm_chip *chip, u8 *buf, size_t count)
 	return size;
 }
 
-/*
- * tpm_ioserirq_handler the serirq irq handler
- * @param: irq, the tpm chip description
- * @param: dev_id, the description of the chip
- * @return: the status of the handler.
- */
 static irqreturn_t tpm_ioserirq_handler(int irq, void *dev_id)
 {
 	struct tpm_chip *chip = dev_id;
@@ -341,16 +293,10 @@ static irqreturn_t tpm_ioserirq_handler(int irq, void *dev_id)
 	disable_irq_nosync(tpm_dev->irq);
 
 	return IRQ_HANDLED;
-} /* tpm_ioserirq_handler() */
+}
 
 /*
- * st33zp24_send send TPM commands through the I2C bus.
- *
- * @param: chip, the tpm_chip description as specified in driver/char/tpm/tpm.h
- * @param: buf,	the buffer to send.
- * @param: count, the number of bytes to send.
- * @return: In case of success the number of bytes sent.
- *			In other case, a < 0 value describing the issue.
+ * send TPM commands through the I2C bus.
  */
 static int st33zp24_send(struct tpm_chip *chip, unsigned char *buf,
 			 size_t len)
@@ -431,14 +377,6 @@ out_err:
 	return ret;
 }
 
-/*
- * st33zp24_recv received TPM response through TPM phy.
- * @param: chip, the tpm_chip description as specified in driver/char/tpm/tpm.h.
- * @param: buf,	the buffer to store datas.
- * @param: count, the number of bytes to send.
- * @return: In case of success the number of bytes received.
- *	    In other case, a < 0 value describing the issue.
- */
 static int st33zp24_recv(struct tpm_chip *chip, unsigned char *buf,
 			    size_t count)
 {
@@ -478,12 +416,6 @@ out:
 	return size;
 }
 
-/*
- * st33zp24_req_canceled
- * @param: chip, the tpm_chip description as specified in driver/char/tpm/tpm.h.
- * @param: status, the TPM status.
- * @return: Does TPM ready to compute a new command ? true.
- */
 static bool st33zp24_req_canceled(struct tpm_chip *chip, u8 status)
 {
 	return (status == TPM_STS_COMMAND_READY);
@@ -501,11 +433,7 @@ static const struct tpm_class_ops st33zp24_tpm = {
 };
 
 /*
- * st33zp24_probe initialize the TPM device
- * @param: client, the i2c_client description (TPM I2C description).
- * @param: id, the i2c_device_id struct.
- * @return: 0 in case of success.
- *	 -1 in other case.
+ * initialize the TPM device
  */
 int st33zp24_probe(void *phy_id, const struct st33zp24_phy_ops *ops,
 		   struct device *dev, int irq, int io_lpcpd)
@@ -583,11 +511,6 @@ _tpm_clean_answer:
 }
 EXPORT_SYMBOL(st33zp24_probe);
 
-/*
- * st33zp24_remove remove the TPM device
- * @param: tpm_data, the tpm phy.
- * @return: 0 in case of success.
- */
 int st33zp24_remove(struct tpm_chip *chip)
 {
 	tpm_chip_unregister(chip);
@@ -596,12 +519,6 @@ int st33zp24_remove(struct tpm_chip *chip)
 EXPORT_SYMBOL(st33zp24_remove);
 
 #ifdef CONFIG_PM_SLEEP
-/*
- * st33zp24_pm_suspend suspend the TPM device
- * @param: tpm_data, the tpm phy.
- * @param: mesg, the power management message.
- * @return: 0 in case of success.
- */
 int st33zp24_pm_suspend(struct device *dev)
 {
 	struct tpm_chip *chip = dev_get_drvdata(dev);
@@ -615,14 +532,9 @@ int st33zp24_pm_suspend(struct device *dev)
 		ret = tpm_pm_suspend(dev);
 
 	return ret;
-} /* st33zp24_pm_suspend() */
+}
 EXPORT_SYMBOL(st33zp24_pm_suspend);
 
-/*
- * st33zp24_pm_resume resume the TPM device
- * @param: tpm_data, the tpm phy.
- * @return: 0 in case of success.