tpm: Export the open/close functions

At present these functions are not accessible outside the TPM library, but in some cases we need to call them. Export them in the header file and add a define for the SHA1 digest size. Also adjust tpm_open() to call tpm_close() first so that the TPM is in a known state before opening (e.g. by a previous phase of U-Boot). Signed-off-by: Simon Glass <[email protected]>
pthomas · Nov 29, 2018 · 51f00c1 · 51f00c1
1 parent 07e127d
commit 51f00c1
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Showing 3 changed files with 45 additions and 38 deletions.
diff --git a/drivers/tpm/tpm_tis_lpc.c b/drivers/tpm/tpm_tis_lpc.c
@@ -388,13 +388,40 @@ static int tis_readresponse(struct udevice *dev, u8 *buffer, size_t len)
 	return offset;
 }
 
+static int tpm_tis_lpc_close(struct udevice *dev)
+{
+	struct tpm_tis_lpc_priv *priv = dev_get_priv(dev);
+	struct tpm_locality *regs = priv->regs;
+	u8 locality = 0;
+
+	if (tpm_read_word(priv, &regs[locality].access) &
+	    TIS_ACCESS_ACTIVE_LOCALITY) {
+		tpm_write_word(priv, TIS_ACCESS_ACTIVE_LOCALITY,
+			       &regs[locality].access);
+
+		if (tis_wait_reg(priv, &regs[locality].access,
+				 TIS_ACCESS_ACTIVE_LOCALITY, 0) == -ETIMEDOUT) {
+			printf("%s:%d - failed to release locality %d\n",
+			       __FILE__, __LINE__, locality);
+			return -ETIMEDOUT;
+		}
+	}
+	return 0;
+}
+
 static int tpm_tis_lpc_open(struct udevice *dev)
 {
 	struct tpm_tis_lpc_priv *priv = dev_get_priv(dev);
 	struct tpm_locality *regs = priv->regs;
 	u8 locality = 0; /* we use locality zero for everything. */
 	int ret;
 
+	ret = tpm_tis_lpc_close(dev);
+	if (ret) {
+		printf("%s: Failed to close TPM\n", __func__);
+		return ret;
+	}
+
 	/* now request access to locality. */
 	tpm_write_word(priv, TIS_ACCESS_REQUEST_USE, &regs[locality].access);
 
@@ -410,27 +437,7 @@ static int tpm_tis_lpc_open(struct udevice *dev)
 
 	tpm_write_word(priv, TIS_STS_COMMAND_READY,
 		       &regs[locality].tpm_status);
-	return 0;
-}
-
-static int tpm_tis_lpc_close(struct udevice *dev)
-{
-	struct tpm_tis_lpc_priv *priv = dev_get_priv(dev);
-	struct tpm_locality *regs = priv->regs;
-	u8 locality = 0;
-
-	if (tpm_read_word(priv, &regs[locality].access) &
-	    TIS_ACCESS_ACTIVE_LOCALITY) {
-		tpm_write_word(priv, TIS_ACCESS_ACTIVE_LOCALITY,
-			       &regs[locality].access);
 
-		if (tis_wait_reg(priv, &regs[locality].access,
-				 TIS_ACCESS_ACTIVE_LOCALITY, 0) == -ETIMEDOUT) {
-			printf("%s:%d - failed to release locality %d\n",
-			       __FILE__, __LINE__, locality);
-			return -ETIMEDOUT;
-		}
-	}
 	return 0;
 }
 

diff --git a/include/tpm-common.h b/include/tpm-common.h
@@ -181,6 +181,24 @@ int do_##cmd(cmd_tbl_t *cmdtp, int flag,		\
 	return report_return_code(cmd());		\
 }
 
+/**
+ * tpm_open() - Request access to locality 0 for the caller
+ *
+ * After all commands have been completed the caller is supposed to
+ * call tpm_close().
+ *
+ * Returns 0 on success, -ve on failure.
+ */
+int tpm_open(struct udevice *dev);
+
+/**
+ * tpm_close() - Close the current session
+ *
+ * Releasing the locked locality. Returns 0 on success, -ve 1 on
+ * failure (in case lock removal did not succeed).
+ */
+int tpm_close(struct udevice *dev);
+
 /**
  * tpm_get_desc() - Get a text description of the TPM
  *

diff --git a/lib/tpm-utils.h b/lib/tpm-utils.h
@@ -18,24 +18,6 @@
 #define tpm_u16(x) __MSB(x), __LSB(x)
 #define tpm_u32(x) tpm_u16((x) >> 16), tpm_u16((x) & 0xFFFF)
 
-/**
- * tpm_open() - Request access to locality 0 for the caller
- *
- * After all commands have been completed the caller is supposed to
- * call tpm_close().
- *
- * Returns 0 on success, -ve on failure.
- */
-int tpm_open(struct udevice *dev);
-
-/**
- * tpm_close() - Close the current session
- *
- * Releasing the locked locality. Returns 0 on success, -ve 1 on
- * failure (in case lock removal did not succeed).
- */
-int tpm_close(struct udevice *dev);
-
 /**
  * Pack data into a byte string.  The data types are specified in
  * the format string: 'b' means unsigned byte, 'w' unsigned word,