]> pilppa.org Git - linux-2.6-omap-h63xx.git/blobdiff - drivers/char/tpm/tpm.c
Merge branch 'release' of git://git.kernel.org/pub/scm/linux/kernel/git/lenb/linux...
[linux-2.6-omap-h63xx.git] / drivers / char / tpm / tpm.c
index 50013eb8cf1ec205f09f97b318eb5bf336a64715..6889e7db3aff5285dd7824317c3f6469fc2e00c2 100644 (file)
@@ -32,12 +32,291 @@ enum tpm_const {
        TPM_MINOR = 224,        /* officially assigned */
        TPM_BUFSIZE = 2048,
        TPM_NUM_DEVICES = 256,
-       TPM_NUM_MASK_ENTRIES = TPM_NUM_DEVICES / (8 * sizeof(int))
 };
 
+enum tpm_duration {
+       TPM_SHORT = 0,
+       TPM_MEDIUM = 1,
+       TPM_LONG = 2,
+       TPM_UNDEFINED,
+};
+
+#define TPM_MAX_ORDINAL 243
+#define TPM_MAX_PROTECTED_ORDINAL 12
+#define TPM_PROTECTED_ORDINAL_MASK 0xFF
+
 static LIST_HEAD(tpm_chip_list);
 static DEFINE_SPINLOCK(driver_lock);
-static int dev_mask[TPM_NUM_MASK_ENTRIES];
+static DECLARE_BITMAP(dev_mask, TPM_NUM_DEVICES);
+
+/*
+ * Array with one entry per ordinal defining the maximum amount
+ * of time the chip could take to return the result.  The ordinal
+ * designation of short, medium or long is defined in a table in
+ * TCG Specification TPM Main Part 2 TPM Structures Section 17. The
+ * values of the SHORT, MEDIUM, and LONG durations are retrieved
+ * from the chip during initialization with a call to tpm_get_timeouts.
+ */
+static const u8 tpm_protected_ordinal_duration[TPM_MAX_PROTECTED_ORDINAL] = {
+       TPM_UNDEFINED,          /* 0 */
+       TPM_UNDEFINED,
+       TPM_UNDEFINED,
+       TPM_UNDEFINED,
+       TPM_UNDEFINED,
+       TPM_UNDEFINED,          /* 5 */
+       TPM_UNDEFINED,
+       TPM_UNDEFINED,
+       TPM_UNDEFINED,
+       TPM_UNDEFINED,
+       TPM_SHORT,              /* 10 */
+       TPM_SHORT,
+};
+
+static const u8 tpm_ordinal_duration[TPM_MAX_ORDINAL] = {
+       TPM_UNDEFINED,          /* 0 */
+       TPM_UNDEFINED,
+       TPM_UNDEFINED,
+       TPM_UNDEFINED,
+       TPM_UNDEFINED,
+       TPM_UNDEFINED,          /* 5 */
+       TPM_UNDEFINED,
+       TPM_UNDEFINED,
+       TPM_UNDEFINED,
+       TPM_UNDEFINED,
+       TPM_SHORT,              /* 10 */
+       TPM_SHORT,
+       TPM_MEDIUM,
+       TPM_LONG,
+       TPM_LONG,
+       TPM_MEDIUM,             /* 15 */
+       TPM_SHORT,
+       TPM_SHORT,
+       TPM_MEDIUM,
+       TPM_LONG,
+       TPM_SHORT,              /* 20 */
+       TPM_SHORT,
+       TPM_MEDIUM,
+       TPM_MEDIUM,
+       TPM_MEDIUM,
+       TPM_SHORT,              /* 25 */
+       TPM_SHORT,
+       TPM_MEDIUM,
+       TPM_SHORT,
+       TPM_SHORT,
+       TPM_MEDIUM,             /* 30 */
+       TPM_LONG,
+       TPM_MEDIUM,
+       TPM_SHORT,
+       TPM_SHORT,
+       TPM_SHORT,              /* 35 */
+       TPM_MEDIUM,
+       TPM_MEDIUM,
+       TPM_UNDEFINED,
+       TPM_UNDEFINED,
+       TPM_MEDIUM,             /* 40 */
+       TPM_LONG,
+       TPM_MEDIUM,
+       TPM_SHORT,
+       TPM_SHORT,
+       TPM_SHORT,              /* 45 */
+       TPM_SHORT,
+       TPM_SHORT,
+       TPM_SHORT,
+       TPM_LONG,
+       TPM_MEDIUM,             /* 50 */
+       TPM_MEDIUM,
+       TPM_UNDEFINED,
+       TPM_UNDEFINED,
+       TPM_UNDEFINED,
+       TPM_UNDEFINED,          /* 55 */
+       TPM_UNDEFINED,
+       TPM_UNDEFINED,
+       TPM_UNDEFINED,
+       TPM_UNDEFINED,
+       TPM_MEDIUM,             /* 60 */
+       TPM_MEDIUM,
+       TPM_MEDIUM,
+       TPM_SHORT,
+       TPM_SHORT,
+       TPM_MEDIUM,             /* 65 */
+       TPM_UNDEFINED,
+       TPM_UNDEFINED,
+       TPM_UNDEFINED,
+       TPM_UNDEFINED,
+       TPM_SHORT,              /* 70 */
+       TPM_SHORT,
+       TPM_UNDEFINED,
+       TPM_UNDEFINED,
+       TPM_UNDEFINED,
+       TPM_UNDEFINED,          /* 75 */
+       TPM_UNDEFINED,
+       TPM_UNDEFINED,
+       TPM_UNDEFINED,
+       TPM_UNDEFINED,
+       TPM_LONG,               /* 80 */
+       TPM_UNDEFINED,
+       TPM_MEDIUM,
+       TPM_LONG,
+       TPM_SHORT,
+       TPM_UNDEFINED,          /* 85 */
+       TPM_UNDEFINED,
+       TPM_UNDEFINED,
+       TPM_UNDEFINED,
+       TPM_UNDEFINED,
+       TPM_SHORT,              /* 90 */
+       TPM_SHORT,
+       TPM_SHORT,
+       TPM_SHORT,
+       TPM_SHORT,
+       TPM_UNDEFINED,          /* 95 */
+       TPM_UNDEFINED,
+       TPM_UNDEFINED,
+       TPM_UNDEFINED,
+       TPM_UNDEFINED,
+       TPM_MEDIUM,             /* 100 */
+       TPM_SHORT,
+       TPM_SHORT,
+       TPM_UNDEFINED,
+       TPM_UNDEFINED,
+       TPM_UNDEFINED,          /* 105 */
+       TPM_UNDEFINED,
+       TPM_UNDEFINED,
+       TPM_UNDEFINED,
+       TPM_UNDEFINED,
+       TPM_SHORT,              /* 110 */
+       TPM_SHORT,
+       TPM_SHORT,
+       TPM_SHORT,
+       TPM_SHORT,
+       TPM_SHORT,              /* 115 */
+       TPM_SHORT,
+       TPM_SHORT,
+       TPM_UNDEFINED,
+       TPM_UNDEFINED,
+       TPM_LONG,               /* 120 */
+       TPM_LONG,
+       TPM_MEDIUM,
+       TPM_UNDEFINED,
+       TPM_SHORT,
+       TPM_SHORT,              /* 125 */
+       TPM_SHORT,
+       TPM_LONG,
+       TPM_SHORT,
+       TPM_SHORT,
+       TPM_SHORT,              /* 130 */
+       TPM_MEDIUM,
+       TPM_UNDEFINED,
+       TPM_SHORT,
+       TPM_MEDIUM,
+       TPM_UNDEFINED,          /* 135 */
+       TPM_UNDEFINED,
+       TPM_UNDEFINED,
+       TPM_UNDEFINED,
+       TPM_UNDEFINED,
+       TPM_SHORT,              /* 140 */
+       TPM_SHORT,
+       TPM_UNDEFINED,
+       TPM_UNDEFINED,
+       TPM_UNDEFINED,
+       TPM_UNDEFINED,          /* 145 */
+       TPM_UNDEFINED,
+       TPM_UNDEFINED,
+       TPM_UNDEFINED,
+       TPM_UNDEFINED,
+       TPM_SHORT,              /* 150 */
+       TPM_MEDIUM,
+       TPM_MEDIUM,
+       TPM_SHORT,
+       TPM_SHORT,
+       TPM_UNDEFINED,          /* 155 */
+       TPM_UNDEFINED,
+       TPM_UNDEFINED,
+       TPM_UNDEFINED,
+       TPM_UNDEFINED,
+       TPM_SHORT,              /* 160 */
+       TPM_SHORT,
+       TPM_SHORT,
+       TPM_SHORT,
+       TPM_UNDEFINED,
+       TPM_UNDEFINED,          /* 165 */
+       TPM_UNDEFINED,
+       TPM_UNDEFINED,
+       TPM_UNDEFINED,
+       TPM_UNDEFINED,
+       TPM_LONG,               /* 170 */
+       TPM_UNDEFINED,
+       TPM_UNDEFINED,
+       TPM_UNDEFINED,
+       TPM_UNDEFINED,
+       TPM_UNDEFINED,          /* 175 */
+       TPM_UNDEFINED,
+       TPM_UNDEFINED,
+       TPM_UNDEFINED,
+       TPM_UNDEFINED,
+       TPM_MEDIUM,             /* 180 */
+       TPM_SHORT,
+       TPM_MEDIUM,
+       TPM_MEDIUM,
+       TPM_MEDIUM,
+       TPM_MEDIUM,             /* 185 */
+       TPM_SHORT,
+       TPM_UNDEFINED,
+       TPM_UNDEFINED,
+       TPM_UNDEFINED,
+       TPM_UNDEFINED,          /* 190 */
+       TPM_UNDEFINED,
+       TPM_UNDEFINED,
+       TPM_UNDEFINED,
+       TPM_UNDEFINED,
+       TPM_UNDEFINED,          /* 195 */
+       TPM_UNDEFINED,
+       TPM_UNDEFINED,
+       TPM_UNDEFINED,
+       TPM_UNDEFINED,
+       TPM_SHORT,              /* 200 */
+       TPM_UNDEFINED,
+       TPM_UNDEFINED,
+       TPM_UNDEFINED,
+       TPM_SHORT,
+       TPM_SHORT,              /* 205 */
+       TPM_SHORT,
+       TPM_SHORT,
+       TPM_SHORT,
+       TPM_SHORT,
+       TPM_MEDIUM,             /* 210 */
+       TPM_UNDEFINED,
+       TPM_MEDIUM,
+       TPM_MEDIUM,
+       TPM_MEDIUM,
+       TPM_UNDEFINED,          /* 215 */
+       TPM_MEDIUM,
+       TPM_UNDEFINED,
+       TPM_UNDEFINED,
+       TPM_SHORT,
+       TPM_SHORT,              /* 220 */
+       TPM_SHORT,
+       TPM_SHORT,
+       TPM_SHORT,
+       TPM_SHORT,
+       TPM_UNDEFINED,          /* 225 */
+       TPM_UNDEFINED,
+       TPM_UNDEFINED,
+       TPM_UNDEFINED,
+       TPM_UNDEFINED,
+       TPM_SHORT,              /* 230 */
+       TPM_LONG,
+       TPM_MEDIUM,
+       TPM_UNDEFINED,
+       TPM_UNDEFINED,
+       TPM_UNDEFINED,          /* 235 */
+       TPM_UNDEFINED,
+       TPM_UNDEFINED,
+       TPM_UNDEFINED,
+       TPM_UNDEFINED,
+       TPM_SHORT,              /* 240 */
+       TPM_UNDEFINED,
+       TPM_MEDIUM,
+};
 
 static void user_reader_timeout(unsigned long ptr)
 {
@@ -56,6 +335,32 @@ static void timeout_work(void *ptr)
        up(&chip->buffer_mutex);
 }
 
+/*
+ * Returns max number of jiffies to wait
+ */
+unsigned long tpm_calc_ordinal_duration(struct tpm_chip *chip,
+                                          u32 ordinal)
+{
+       int duration_idx = TPM_UNDEFINED;
+       int duration = 0;
+
+       if (ordinal < TPM_MAX_ORDINAL)
+               duration_idx = tpm_ordinal_duration[ordinal];
+       else if ((ordinal & TPM_PROTECTED_ORDINAL_MASK) <
+                TPM_MAX_PROTECTED_ORDINAL)
+               duration_idx =
+                   tpm_protected_ordinal_duration[ordinal &
+                                                  TPM_PROTECTED_ORDINAL_MASK];
+
+       if (duration_idx != TPM_UNDEFINED)
+               duration = chip->vendor.duration[duration_idx];
+       if (duration <= 0)
+               return 2 * 60 * HZ;
+       else
+               return duration;
+}
+EXPORT_SYMBOL_GPL(tpm_calc_ordinal_duration);
+
 /*
  * Internal kernel interface to transmit TPM commands
  */
@@ -63,11 +368,11 @@ static ssize_t tpm_transmit(struct tpm_chip *chip, const char *buf,
                            size_t bufsiz)
 {
        ssize_t rc;
-       u32 count;
+       u32 count, ordinal;
        unsigned long stop;
 
        count = be32_to_cpu(*((__be32 *) (buf + 2)));
-
+       ordinal = be32_to_cpu(*((__be32 *) (buf + 6)));
        if (count == 0)
                return -ENODATA;
        if (count > bufsiz) {
@@ -84,7 +389,10 @@ static ssize_t tpm_transmit(struct tpm_chip *chip, const char *buf,
                goto out;
        }
 
-       stop = jiffies + 2 * 60 * HZ;
+       if (chip->vendor.irq)
+               goto out_recv;
+
+       stop = jiffies + tpm_calc_ordinal_duration(chip, ordinal);
        do {
                u8 status = chip->vendor.status(chip);
                if ((status & chip->vendor.req_complete_mask) ==
@@ -124,17 +432,27 @@ out:
 #define TPM_GET_CAP_RET_UINT32_2_IDX 18
 #define TPM_GET_CAP_RET_UINT32_3_IDX 22
 #define TPM_GET_CAP_RET_UINT32_4_IDX 26
+#define TPM_GET_CAP_PERM_DISABLE_IDX 16
+#define TPM_GET_CAP_PERM_INACTIVE_IDX 18
+#define TPM_GET_CAP_RET_BOOL_1_IDX 14
+#define TPM_GET_CAP_TEMP_INACTIVE_IDX 16
 
 #define TPM_CAP_IDX 13
 #define TPM_CAP_SUBCAP_IDX 21
 
 enum tpm_capabilities {
+       TPM_CAP_FLAG = 4,
        TPM_CAP_PROP = 5,
 };
 
 enum tpm_sub_capabilities {
        TPM_CAP_PROP_PCR = 0x1,
        TPM_CAP_PROP_MANUFACTURER = 0x3,
+       TPM_CAP_FLAG_PERM = 0x8,
+       TPM_CAP_FLAG_VOL = 0x9,
+       TPM_CAP_PROP_OWNER = 0x11,
+       TPM_CAP_PROP_TIS_TIMEOUT = 0x15,
+       TPM_CAP_PROP_TIS_DURATION = 0x20,
 };
 
 /*
@@ -168,6 +486,186 @@ static ssize_t transmit_cmd(struct tpm_chip *chip, u8 *data, int len,
        return 0;
 }
 
+void tpm_gen_interrupt(struct tpm_chip *chip)
+{
+       u8 data[max_t(int, ARRAY_SIZE(tpm_cap), 30)];
+       ssize_t rc;
+
+       memcpy(data, tpm_cap, sizeof(tpm_cap));
+       data[TPM_CAP_IDX] = TPM_CAP_PROP;
+       data[TPM_CAP_SUBCAP_IDX] = TPM_CAP_PROP_TIS_TIMEOUT;
+
+       rc = transmit_cmd(chip, data, sizeof(data),
+                       "attempting to determine the timeouts");
+}
+EXPORT_SYMBOL_GPL(tpm_gen_interrupt);
+
+void tpm_get_timeouts(struct tpm_chip *chip)
+{
+       u8 data[max_t(int, ARRAY_SIZE(tpm_cap), 30)];
+       ssize_t rc;
+       u32 timeout;
+
+       memcpy(data, tpm_cap, sizeof(tpm_cap));
+       data[TPM_CAP_IDX] = TPM_CAP_PROP;
+       data[TPM_CAP_SUBCAP_IDX] = TPM_CAP_PROP_TIS_TIMEOUT;
+
+       rc = transmit_cmd(chip, data, sizeof(data),
+                       "attempting to determine the timeouts");
+       if (rc)
+               goto duration;
+
+       if (be32_to_cpu(*((__be32 *) (data + TPM_GET_CAP_RET_SIZE_IDX)))
+           != 4 * sizeof(u32))
+               goto duration;
+
+       /* Don't overwrite default if value is 0 */
+       timeout =
+           be32_to_cpu(*((__be32 *) (data + TPM_GET_CAP_RET_UINT32_1_IDX)));
+       if (timeout)
+               chip->vendor.timeout_a = msecs_to_jiffies(timeout);
+       timeout =
+           be32_to_cpu(*((__be32 *) (data + TPM_GET_CAP_RET_UINT32_2_IDX)));
+       if (timeout)
+               chip->vendor.timeout_b = msecs_to_jiffies(timeout);
+       timeout =
+           be32_to_cpu(*((__be32 *) (data + TPM_GET_CAP_RET_UINT32_3_IDX)));
+       if (timeout)
+               chip->vendor.timeout_c = msecs_to_jiffies(timeout);
+       timeout =
+           be32_to_cpu(*((__be32 *) (data + TPM_GET_CAP_RET_UINT32_4_IDX)));
+       if (timeout)
+               chip->vendor.timeout_d = msecs_to_jiffies(timeout);
+
+duration:
+       memcpy(data, tpm_cap, sizeof(tpm_cap));
+       data[TPM_CAP_IDX] = TPM_CAP_PROP;
+       data[TPM_CAP_SUBCAP_IDX] = TPM_CAP_PROP_TIS_DURATION;
+
+       rc = transmit_cmd(chip, data, sizeof(data),
+                       "attempting to determine the durations");
+       if (rc)
+               return;
+
+       if (be32_to_cpu(*((__be32 *) (data + TPM_GET_CAP_RET_SIZE_IDX)))
+           != 3 * sizeof(u32))
+               return;
+
+       chip->vendor.duration[TPM_SHORT] =
+           msecs_to_jiffies(be32_to_cpu
+                            (*((__be32 *) (data +
+                                           TPM_GET_CAP_RET_UINT32_1_IDX))));
+       chip->vendor.duration[TPM_MEDIUM] =
+           msecs_to_jiffies(be32_to_cpu
+                            (*((__be32 *) (data +
+                                           TPM_GET_CAP_RET_UINT32_2_IDX))));
+       chip->vendor.duration[TPM_LONG] =
+           msecs_to_jiffies(be32_to_cpu
+                            (*((__be32 *) (data +
+                                           TPM_GET_CAP_RET_UINT32_3_IDX))));
+}
+EXPORT_SYMBOL_GPL(tpm_get_timeouts);
+
+void tpm_continue_selftest(struct tpm_chip *chip)
+{
+       u8 data[] = {
+               0, 193,                 /* TPM_TAG_RQU_COMMAND */
+               0, 0, 0, 10,            /* length */
+               0, 0, 0, 83,            /* TPM_ORD_GetCapability */
+       };
+
+       tpm_transmit(chip, data, sizeof(data));
+}
+EXPORT_SYMBOL_GPL(tpm_continue_selftest);
+
+ssize_t tpm_show_enabled(struct device * dev, struct device_attribute * attr,
+                       char *buf)
+{
+       u8 data[max_t(int, ARRAY_SIZE(tpm_cap), 35)];
+       ssize_t rc;
+
+       struct tpm_chip *chip = dev_get_drvdata(dev);
+       if (chip == NULL)
+               return -ENODEV;
+
+       memcpy(data, tpm_cap, sizeof(tpm_cap));
+       data[TPM_CAP_IDX] = TPM_CAP_FLAG;
+       data[TPM_CAP_SUBCAP_IDX] = TPM_CAP_FLAG_PERM;
+
+       rc = transmit_cmd(chip, data, sizeof(data),
+                       "attemtping to determine the permanent state");
+       if (rc)
+               return 0;
+       return sprintf(buf, "%d\n", !data[TPM_GET_CAP_PERM_DISABLE_IDX]);
+}
+EXPORT_SYMBOL_GPL(tpm_show_enabled);
+
+ssize_t tpm_show_active(struct device * dev, struct device_attribute * attr,
+                       char *buf)
+{
+       u8 data[max_t(int, ARRAY_SIZE(tpm_cap), 35)];
+       ssize_t rc;
+
+       struct tpm_chip *chip = dev_get_drvdata(dev);
+       if (chip == NULL)
+               return -ENODEV;
+
+       memcpy(data, tpm_cap, sizeof(tpm_cap));
+       data[TPM_CAP_IDX] = TPM_CAP_FLAG;
+       data[TPM_CAP_SUBCAP_IDX] = TPM_CAP_FLAG_PERM;
+
+       rc = transmit_cmd(chip, data, sizeof(data),
+                       "attemtping to determine the permanent state");
+       if (rc)
+               return 0;
+       return sprintf(buf, "%d\n", !data[TPM_GET_CAP_PERM_INACTIVE_IDX]);
+}
+EXPORT_SYMBOL_GPL(tpm_show_active);
+
+ssize_t tpm_show_owned(struct device * dev, struct device_attribute * attr,
+                       char *buf)
+{
+       u8 data[sizeof(tpm_cap)];
+       ssize_t rc;
+
+       struct tpm_chip *chip = dev_get_drvdata(dev);
+       if (chip == NULL)
+               return -ENODEV;
+
+       memcpy(data, tpm_cap, sizeof(tpm_cap));
+       data[TPM_CAP_IDX] = TPM_CAP_PROP;
+       data[TPM_CAP_SUBCAP_IDX] = TPM_CAP_PROP_OWNER;
+
+       rc = transmit_cmd(chip, data, sizeof(data),
+                       "attempting to determine the owner state");
+       if (rc)
+               return 0;
+       return sprintf(buf, "%d\n", data[TPM_GET_CAP_RET_BOOL_1_IDX]);
+}
+EXPORT_SYMBOL_GPL(tpm_show_owned);
+
+ssize_t tpm_show_temp_deactivated(struct device * dev,
+                               struct device_attribute * attr, char *buf)
+{
+       u8 data[sizeof(tpm_cap)];
+       ssize_t rc;
+
+       struct tpm_chip *chip = dev_get_drvdata(dev);
+       if (chip == NULL)
+               return -ENODEV;
+
+       memcpy(data, tpm_cap, sizeof(tpm_cap));
+       data[TPM_CAP_IDX] = TPM_CAP_FLAG;
+       data[TPM_CAP_SUBCAP_IDX] = TPM_CAP_FLAG_VOL;
+
+       rc = transmit_cmd(chip, data, sizeof(data),
+                       "attempting to determine the temporary state");
+       if (rc)
+               return 0;
+       return sprintf(buf, "%d\n", data[TPM_GET_CAP_TEMP_INACTIVE_IDX]);
+}
+EXPORT_SYMBOL_GPL(tpm_show_temp_deactivated);
+
 static const u8 pcrread[] = {
        0, 193,                 /* TPM_TAG_RQU_COMMAND */
        0, 0, 0, 14,            /* length */
@@ -178,7 +676,7 @@ static const u8 pcrread[] = {
 ssize_t tpm_show_pcrs(struct device *dev, struct device_attribute *attr,
                      char *buf)
 {
-       u8 data[30];
+       u8 data[max_t(int, max(ARRAY_SIZE(tpm_cap), ARRAY_SIZE(pcrread)), 30)];
        ssize_t rc;
        int i, j, num_pcrs;
        __be32 index;
@@ -282,6 +780,7 @@ out:
 EXPORT_SYMBOL_GPL(tpm_show_pubek);
 
 #define CAP_VERSION_1_1 6
+#define CAP_VERSION_1_2 0x1A
 #define CAP_VERSION_IDX 13
 static const u8 cap_version[] = {
        0, 193,                 /* TPM_TAG_RQU_COMMAND */
@@ -294,7 +793,7 @@ static const u8 cap_version[] = {
 ssize_t tpm_show_caps(struct device *dev, struct device_attribute *attr,
                      char *buf)
 {
-       u8 data[30];
+       u8 data[max_t(int, max(ARRAY_SIZE(tpm_cap), ARRAY_SIZE(cap_version)), 30)];
        ssize_t rc;
        char *str = buf;
 
@@ -331,6 +830,52 @@ out:
 }
 EXPORT_SYMBOL_GPL(tpm_show_caps);
 
+ssize_t tpm_show_caps_1_2(struct device * dev,
+                         struct device_attribute * attr, char *buf)
+{
+       u8 data[max_t(int, max(ARRAY_SIZE(tpm_cap), ARRAY_SIZE(cap_version)), 30)];
+       ssize_t len;
+       char *str = buf;
+
+       struct tpm_chip *chip = dev_get_drvdata(dev);
+       if (chip == NULL)
+               return -ENODEV;
+
+       memcpy(data, tpm_cap, sizeof(tpm_cap));
+       data[TPM_CAP_IDX] = TPM_CAP_PROP;
+       data[TPM_CAP_SUBCAP_IDX] = TPM_CAP_PROP_MANUFACTURER;
+
+       if ((len = tpm_transmit(chip, data, sizeof(data))) <=
+           TPM_ERROR_SIZE) {
+               dev_dbg(chip->dev, "A TPM error (%d) occurred "
+                       "attempting to determine the manufacturer\n",
+                       be32_to_cpu(*((__be32 *) (data + TPM_RET_CODE_IDX))));
+               return 0;
+       }
+
+       str += sprintf(str, "Manufacturer: 0x%x\n",
+                      be32_to_cpu(*((__be32 *) (data + TPM_GET_CAP_RET_UINT32_1_IDX))));
+
+       memcpy(data, cap_version, sizeof(cap_version));
+       data[CAP_VERSION_IDX] = CAP_VERSION_1_2;
+
+       if ((len = tpm_transmit(chip, data, sizeof(data))) <=
+           TPM_ERROR_SIZE) {
+               dev_err(chip->dev, "A TPM error (%d) occurred "
+                       "attempting to determine the 1.2 version\n",
+                       be32_to_cpu(*((__be32 *) (data + TPM_RET_CODE_IDX))));
+               goto out;
+       }
+       str += sprintf(str,
+                      "TCG version: %d.%d\nFirmware version: %d.%d\n",
+                      (int) data[16], (int) data[17], (int) data[18],
+                      (int) data[19]);
+
+out:
+       return str - buf;
+}
+EXPORT_SYMBOL_GPL(tpm_show_caps_1_2);
+
 ssize_t tpm_store_cancel(struct device *dev, struct device_attribute *attr,
                        const char *buf, size_t count)
 {
@@ -492,8 +1037,7 @@ void tpm_remove_hardware(struct device *dev)
        sysfs_remove_group(&dev->kobj, chip->vendor.attr_group);
        tpm_bios_log_teardown(chip->bios_dir);
 
-       dev_mask[chip->dev_num / TPM_NUM_MASK_ENTRIES] &=
-           ~(1 << (chip->dev_num % TPM_NUM_MASK_ENTRIES));
+       clear_bit(chip->dev_num, dev_mask);
 
        kfree(chip);
 
@@ -544,18 +1088,18 @@ EXPORT_SYMBOL_GPL(tpm_pm_resume);
  * upon errant exit from this function specific probe function should call
  * pci_disable_device
  */
-int tpm_register_hardware(struct device *dev, struct tpm_vendor_specific *entry)
+struct tpm_chip *tpm_register_hardware(struct device *dev, const struct tpm_vendor_specific
+                                      *entry)
 {
 #define DEVNAME_SIZE 7
 
        char *devname;
        struct tpm_chip *chip;
-       int i, j;
 
        /* Driver specific per-device data */
        chip = kzalloc(sizeof(*chip), GFP_KERNEL);
        if (chip == NULL)
-               return -ENOMEM;
+               return NULL;
 
        init_MUTEX(&chip->buffer_mutex);
        init_MUTEX(&chip->tpm_mutex);
@@ -569,27 +1113,19 @@ int tpm_register_hardware(struct device *dev, struct tpm_vendor_specific *entry)
 
        memcpy(&chip->vendor, entry, sizeof(struct tpm_vendor_specific));
 
-       chip->dev_num = -1;
-
-       for (i = 0; i < TPM_NUM_MASK_ENTRIES; i++)
-               for (j = 0; j < 8 * sizeof(int); j++)
-                       if ((dev_mask[i] & (1 << j)) == 0) {
-                               chip->dev_num =
-                                   i * TPM_NUM_MASK_ENTRIES + j;
-                               dev_mask[i] |= 1 << j;
-                               goto dev_num_search_complete;
-                       }
+       chip->dev_num = find_first_zero_bit(dev_mask, TPM_NUM_DEVICES);
 
-dev_num_search_complete:
-       if (chip->dev_num < 0) {
+       if (chip->dev_num >= TPM_NUM_DEVICES) {
                dev_err(dev, "No available tpm device numbers\n");
                kfree(chip);
-               return -ENODEV;
+               return NULL;
        } else if (chip->dev_num == 0)
                chip->vendor.miscdev.minor = TPM_MINOR;
        else
                chip->vendor.miscdev.minor = MISC_DYNAMIC_MINOR;
 
+       set_bit(chip->dev_num, dev_mask);
+
        devname = kmalloc(DEVNAME_SIZE, GFP_KERNEL);
        scnprintf(devname, DEVNAME_SIZE, "%s%d", "tpm", chip->dev_num);
        chip->vendor.miscdev.name = devname;
@@ -603,9 +1139,9 @@ dev_num_search_complete:
                        chip->vendor.miscdev.name,
                        chip->vendor.miscdev.minor);
                put_device(dev);
+               clear_bit(chip->dev_num, dev_mask);
                kfree(chip);
-               dev_mask[i] &= !(1 << j);
-               return -ENODEV;
+               return NULL;
        }
 
        spin_lock(&driver_lock);
@@ -620,7 +1156,7 @@ dev_num_search_complete:
 
        chip->bios_dir = tpm_bios_log_setup(devname);
 
-       return 0;
+       return chip;
 }
 EXPORT_SYMBOL_GPL(tpm_register_hardware);