X-Git-Url: https://git.openpandora.org/cgi-bin/gitweb.cgi?a=blobdiff_plain;f=drivers%2Fchar%2Ftpm%2Ftpm.c;h=f7395c438a0060f5294f01036d6b922c4cdd6d86;hb=34684322dfc9f75ded03bb67da5309544425ec39;hp=361a1dff8f772e9d1aa2d855300046ca50291c03;hpb=1197ab2942f920f261952de0c392ac749a35796b;p=pandora-kernel.git

diff --git a/drivers/char/tpm/tpm.c b/drivers/char/tpm/tpm.c
index 361a1dff8f77..f7395c438a00 100644
--- a/drivers/char/tpm/tpm.c
+++ b/drivers/char/tpm/tpm.c
@@ -533,11 +533,10 @@ EXPORT_SYMBOL_GPL(tpm_gen_interrupt);
 void tpm_get_timeouts(struct tpm_chip *chip)
 {
 	struct tpm_cmd_t tpm_cmd;
-	struct timeout_t *timeout_cap;
+	unsigned long new_timeout[4];
+	unsigned long old_timeout[4];
 	struct duration_t *duration_cap;
 	ssize_t rc;
-	u32 timeout;
-	unsigned int scale = 1;
 
 	tpm_cmd.header.in = tpm_getcap_header;
 	tpm_cmd.params.getcap_in.cap = TPM_CAP_PROP;
@@ -554,25 +553,46 @@ void tpm_get_timeouts(struct tpm_chip *chip)
 	    != sizeof(tpm_cmd.header.out) + sizeof(u32) + 4 * sizeof(u32))
 		return;
 
-	timeout_cap = &tpm_cmd.params.getcap_out.cap.timeout;
-	/* Don't overwrite default if value is 0 */
-	timeout = be32_to_cpu(timeout_cap->a);
-	if (timeout && timeout < 1000) {
-		/* timeouts in msec rather usec */
-		scale = 1000;
-		chip->vendor.timeout_adjusted = true;
+	old_timeout[0] = be32_to_cpu(tpm_cmd.params.getcap_out.cap.timeout.a);
+	old_timeout[1] = be32_to_cpu(tpm_cmd.params.getcap_out.cap.timeout.b);
+	old_timeout[2] = be32_to_cpu(tpm_cmd.params.getcap_out.cap.timeout.c);
+	old_timeout[3] = be32_to_cpu(tpm_cmd.params.getcap_out.cap.timeout.d);
+	memcpy(new_timeout, old_timeout, sizeof(new_timeout));
+
+	/*
+	 * Provide ability for vendor overrides of timeout values in case
+	 * of misreporting.
+	 */
+	if (chip->vendor.update_timeouts != NULL)
+		chip->vendor.timeout_adjusted =
+			chip->vendor.update_timeouts(chip, new_timeout);
+
+	if (!chip->vendor.timeout_adjusted) {
+		/* Don't overwrite default if value is 0 */
+		if (new_timeout[0] != 0 && new_timeout[0] < 1000) {
+			int i;
+
+			/* timeouts in msec rather usec */
+			for (i = 0; i != ARRAY_SIZE(new_timeout); i++)
+				new_timeout[i] *= 1000;
+			chip->vendor.timeout_adjusted = true;
+		}
 	}
-	if (timeout)
-		chip->vendor.timeout_a = usecs_to_jiffies(timeout * scale);
-	timeout = be32_to_cpu(timeout_cap->b);
-	if (timeout)
-		chip->vendor.timeout_b = usecs_to_jiffies(timeout * scale);
-	timeout = be32_to_cpu(timeout_cap->c);
-	if (timeout)
-		chip->vendor.timeout_c = usecs_to_jiffies(timeout * scale);
-	timeout = be32_to_cpu(timeout_cap->d);
-	if (timeout)
-		chip->vendor.timeout_d = usecs_to_jiffies(timeout * scale);
+
+	/* Report adjusted timeouts */
+	if (chip->vendor.timeout_adjusted) {
+		dev_info(chip->dev,
+			 HW_ERR "Adjusting reported timeouts: A %lu->%luus B %lu->%luus C %lu->%luus D %lu->%luus\n",
+			 old_timeout[0], new_timeout[0],
+			 old_timeout[1], new_timeout[1],
+			 old_timeout[2], new_timeout[2],
+			 old_timeout[3], new_timeout[3]);
+	}
+
+	chip->vendor.timeout_a = usecs_to_jiffies(new_timeout[0]);
+	chip->vendor.timeout_b = usecs_to_jiffies(new_timeout[1]);
+	chip->vendor.timeout_c = usecs_to_jiffies(new_timeout[2]);
+	chip->vendor.timeout_d = usecs_to_jiffies(new_timeout[3]);
 
 duration:
 	tpm_cmd.header.in = tpm_getcap_header;
@@ -1072,17 +1092,20 @@ ssize_t tpm_write(struct file *file, const char __user *buf,
 		  size_t size, loff_t *off)
 {
 	struct tpm_chip *chip = file->private_data;
-	size_t in_size = size, out_size;
+	size_t in_size = size;
+	ssize_t out_size;
 
 	/* cannot perform a write until the read has cleared
-	   either via tpm_read or a user_read_timer timeout */
-	while (atomic_read(&chip->data_pending) != 0)
-		msleep(TPM_TIMEOUT);
-
-	mutex_lock(&chip->buffer_mutex);
+	   either via tpm_read or a user_read_timer timeout.
+	   This also prevents splitted buffered writes from blocking here.
+	*/
+	if (atomic_read(&chip->data_pending) != 0)
+		return -EBUSY;
 
 	if (in_size > TPM_BUFSIZE)
-		in_size = TPM_BUFSIZE;
+		return -E2BIG;
+
+	mutex_lock(&chip->buffer_mutex);
 
 	if (copy_from_user
 	    (chip->data_buffer, (void __user *) buf, in_size)) {
@@ -1092,6 +1115,10 @@ ssize_t tpm_write(struct file *file, const char __user *buf,
 
 	/* atomic tpm command send and result receive */
 	out_size = tpm_transmit(chip, chip->data_buffer, TPM_BUFSIZE);
+	if (out_size < 0) {
+		mutex_unlock(&chip->buffer_mutex);
+		return out_size;
+	}
 
 	atomic_set(&chip->data_pending, out_size);
 	mutex_unlock(&chip->buffer_mutex);
@@ -1115,12 +1142,13 @@ ssize_t tpm_read(struct file *file, char __user *buf,
 	ret_size = atomic_read(&chip->data_pending);
 	atomic_set(&chip->data_pending, 0);
 	if (ret_size > 0) {	/* relay data */
+		ssize_t orig_ret_size = ret_size;
 		if (size < ret_size)
 			ret_size = size;
 
 		mutex_lock(&chip->buffer_mutex);
 		rc = copy_to_user(buf, chip->data_buffer, ret_size);
-		memset(chip->data_buffer, 0, ret_size);
+		memset(chip->data_buffer, 0, orig_ret_size);
 		if (rc)
 			ret_size = -EFAULT;
 
@@ -1313,7 +1341,7 @@ struct tpm_chip *tpm_register_hardware(struct device *dev,
 
 	/* Make chip available */
 	spin_lock(&driver_lock);
-	list_add_rcu(&chip->list, &tpm_chip_list);
+	list_add_tail_rcu(&chip->list, &tpm_chip_list);
 	spin_unlock(&driver_lock);
 
 	return chip;