Merge branch 'tpmdd-04-17-13' of git://github.com/shpedoikal/linux in…

…to my-next
mariux64 · Apr 20, 2013 · b7ae9f0 · b7ae9f0
2 parents df2c2af + 32d33b2
commit b7ae9f0
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Showing 6 changed files with 207 additions and 87 deletions.
diff --git a/Documentation/devicetree/bindings/i2c/trivial-devices.txt b/Documentation/devicetree/bindings/i2c/trivial-devices.txt
@@ -35,6 +35,8 @@ fsl,mc13892		MC13892: Power Management Integrated Circuit (PMIC) for i.MX35/51
 fsl,mma8450		MMA8450Q: Xtrinsic Low-power, 3-axis Xtrinsic Accelerometer
 fsl,mpr121		MPR121: Proximity Capacitive Touch Sensor Controller
 fsl,sgtl5000		SGTL5000: Ultra Low-Power Audio Codec
+infineon,slb9635tt	Infineon SLB9635 (Soft-) I2C TPM (old protocol, max 100khz)
+infineon,slb9645tt	Infineon SLB9645 I2C TPM (new protocol, max 400khz)
 maxim,ds1050		5 Bit Programmable, Pulse-Width Modulator
 maxim,max1237		Low-Power, 4-/12-Channel, 2-Wire Serial, 12-Bit ADCs
 maxim,max6625		9-Bit/12-Bit Temperature Sensors with I²C-Compatible Serial Interface

diff --git a/drivers/char/tpm/tpm.c b/drivers/char/tpm/tpm.c
@@ -1337,7 +1337,7 @@ int tpm_pm_suspend(struct device *dev)
 {
 	struct tpm_chip *chip = dev_get_drvdata(dev);
 	struct tpm_cmd_t cmd;
-	int rc;
+	int rc, try;
 
 	u8 dummy_hash[TPM_DIGEST_SIZE] = { 0 };
 
@@ -1355,9 +1355,32 @@ int tpm_pm_suspend(struct device *dev)
 	}
 
 	/* now do the actual savestate */
-	cmd.header.in = savestate_header;
-	rc = transmit_cmd(chip, &cmd, SAVESTATE_RESULT_SIZE,
-			  "sending savestate before suspend");
+	for (try = 0; try < TPM_RETRY; try++) {
+		cmd.header.in = savestate_header;
+		rc = transmit_cmd(chip, &cmd, SAVESTATE_RESULT_SIZE, NULL);
+
+		/*
+		 * If the TPM indicates that it is too busy to respond to
+		 * this command then retry before giving up.  It can take
+		 * several seconds for this TPM to be ready.
+		 *
+		 * This can happen if the TPM has already been sent the
+		 * SaveState command before the driver has loaded.  TCG 1.2
+		 * specification states that any communication after SaveState
+		 * may cause the TPM to invalidate previously saved state.
+		 */
+		if (rc != TPM_WARN_RETRY)
+			break;
+		msleep(TPM_TIMEOUT_RETRY);
+	}
+
+	if (rc)
+		dev_err(chip->dev,
+			"Error (%d) sending savestate before suspend\n", rc);
+	else if (try > 0)
+		dev_warn(chip->dev, "TPM savestate took %dms\n",
+			 try * TPM_TIMEOUT_RETRY);
+
 	return rc;
 }
 EXPORT_SYMBOL_GPL(tpm_pm_suspend);

diff --git a/drivers/char/tpm/tpm.h b/drivers/char/tpm/tpm.h
@@ -32,10 +32,12 @@ enum tpm_const {
 	TPM_MINOR = 224,	/* officially assigned */
 	TPM_BUFSIZE = 4096,
 	TPM_NUM_DEVICES = 256,
+	TPM_RETRY = 50,		/* 5 seconds */
 };
 
 enum tpm_timeout {
 	TPM_TIMEOUT = 5,	/* msecs */
+	TPM_TIMEOUT_RETRY = 100 /* msecs */
 };
 
 /* TPM addresses */
@@ -44,6 +46,7 @@ enum tpm_addr {
 	TPM_ADDR = 0x4E,
 };
 
+#define TPM_WARN_RETRY          0x800
 #define TPM_WARN_DOING_SELFTEST 0x802
 #define TPM_ERR_DEACTIVATED     0x6
 #define TPM_ERR_DISABLED        0x7