Merge branch 'for-james' of git://github.com/srajiv/tpm into next
[firefly-linux-kernel-4.4.55.git] / drivers / char / tpm / tpm.c
index 361a1dff8f772e9d1aa2d855300046ca50291c03..6a8771f47a55c799866468fe80946a479a0440f8 100644 (file)
@@ -27,6 +27,7 @@
 #include <linux/slab.h>
 #include <linux/mutex.h>
 #include <linux/spinlock.h>
+#include <linux/freezer.h>
 
 #include "tpm.h"
 
@@ -440,7 +441,6 @@ out:
 }
 
 #define TPM_DIGEST_SIZE 20
-#define TPM_ERROR_SIZE 10
 #define TPM_RET_CODE_IDX 6
 
 enum tpm_capabilities {
@@ -469,12 +469,14 @@ static ssize_t transmit_cmd(struct tpm_chip *chip, struct tpm_cmd_t *cmd,
        len = tpm_transmit(chip,(u8 *) cmd, len);
        if (len <  0)
                return len;
-       if (len == TPM_ERROR_SIZE) {
-               err = be32_to_cpu(cmd->header.out.return_code);
-               dev_dbg(chip->dev, "A TPM error (%d) occurred %s\n", err, desc);
-               return err;
-       }
-       return 0;
+       else if (len < TPM_HEADER_SIZE)
+               return -EFAULT;
+
+       err = be32_to_cpu(cmd->header.out.return_code);
+       if (err != 0)
+               dev_err(chip->dev, "A TPM error (%d) occurred %s\n", err, desc);
+
+       return err;
 }
 
 #define TPM_INTERNAL_RESULT_SIZE 200
@@ -530,7 +532,7 @@ void tpm_gen_interrupt(struct tpm_chip *chip)
 }
 EXPORT_SYMBOL_GPL(tpm_gen_interrupt);
 
-void tpm_get_timeouts(struct tpm_chip *chip)
+int tpm_get_timeouts(struct tpm_chip *chip)
 {
        struct tpm_cmd_t tpm_cmd;
        struct timeout_t *timeout_cap;
@@ -552,7 +554,7 @@ void tpm_get_timeouts(struct tpm_chip *chip)
        if (be32_to_cpu(tpm_cmd.header.out.return_code) != 0 ||
            be32_to_cpu(tpm_cmd.header.out.length)
            != sizeof(tpm_cmd.header.out) + sizeof(u32) + 4 * sizeof(u32))
-               return;
+               return -EINVAL;
 
        timeout_cap = &tpm_cmd.params.getcap_out.cap.timeout;
        /* Don't overwrite default if value is 0 */
@@ -583,12 +585,12 @@ duration:
        rc = transmit_cmd(chip, &tpm_cmd, TPM_INTERNAL_RESULT_SIZE,
                        "attempting to determine the durations");
        if (rc)
-               return;
+               return rc;
 
        if (be32_to_cpu(tpm_cmd.header.out.return_code) != 0 ||
            be32_to_cpu(tpm_cmd.header.out.length)
            != sizeof(tpm_cmd.header.out) + sizeof(u32) + 3 * sizeof(u32))
-               return;
+               return -EINVAL;
 
        duration_cap = &tpm_cmd.params.getcap_out.cap.duration;
        chip->vendor.duration[TPM_SHORT] =
@@ -610,20 +612,36 @@ duration:
                chip->vendor.duration_adjusted = true;
                dev_info(chip->dev, "Adjusting TPM timeout parameters.");
        }
+       return 0;
 }
 EXPORT_SYMBOL_GPL(tpm_get_timeouts);
 
-void tpm_continue_selftest(struct tpm_chip *chip)
+#define TPM_ORD_CONTINUE_SELFTEST 83
+#define CONTINUE_SELFTEST_RESULT_SIZE 10
+
+static struct tpm_input_header continue_selftest_header = {
+       .tag = TPM_TAG_RQU_COMMAND,
+       .length = cpu_to_be32(10),
+       .ordinal = cpu_to_be32(TPM_ORD_CONTINUE_SELFTEST),
+};
+
+/**
+ * tpm_continue_selftest -- run TPM's selftest
+ * @chip: TPM chip to use
+ *
+ * Returns 0 on success, < 0 in case of fatal error or a value > 0 representing
+ * a TPM error code.
+ */
+static int 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_ContinueSelfTest */
-       };
+       int rc;
+       struct tpm_cmd_t cmd;
 
-       tpm_transmit(chip, data, sizeof(data));
+       cmd.header.in = continue_selftest_header;
+       rc = transmit_cmd(chip, &cmd, CONTINUE_SELFTEST_RESULT_SIZE,
+                         "continue selftest");
+       return rc;
 }
-EXPORT_SYMBOL_GPL(tpm_continue_selftest);
 
 ssize_t tpm_show_enabled(struct device * dev, struct device_attribute * attr,
                        char *buf)
@@ -718,7 +736,7 @@ static struct tpm_input_header pcrread_header = {
        .ordinal = TPM_ORDINAL_PCRREAD
 };
 
-int __tpm_pcr_read(struct tpm_chip *chip, int pcr_idx, u8 *res_buf)
+static int __tpm_pcr_read(struct tpm_chip *chip, int pcr_idx, u8 *res_buf)
 {
        int rc;
        struct tpm_cmd_t cmd;
@@ -798,6 +816,45 @@ int tpm_pcr_extend(u32 chip_num, int pcr_idx, const u8 *hash)
 }
 EXPORT_SYMBOL_GPL(tpm_pcr_extend);
 
+/**
+ * tpm_do_selftest - have the TPM continue its selftest and wait until it
+ *                   can receive further commands
+ * @chip: TPM chip to use
+ *
+ * Returns 0 on success, < 0 in case of fatal error or a value > 0 representing
+ * a TPM error code.
+ */
+int tpm_do_selftest(struct tpm_chip *chip)
+{
+       int rc;
+       u8 digest[TPM_DIGEST_SIZE];
+       unsigned int loops;
+       unsigned int delay_msec = 1000;
+       unsigned long duration;
+
+       duration = tpm_calc_ordinal_duration(chip,
+                                            TPM_ORD_CONTINUE_SELFTEST);
+
+       loops = jiffies_to_msecs(duration) / delay_msec;
+
+       rc = tpm_continue_selftest(chip);
+       /* This may fail if there was no TPM driver during a suspend/resume
+        * cycle; some may return 10 (BAD_ORDINAL), others 28 (FAILEDSELFTEST)
+        */
+       if (rc)
+               return rc;
+
+       do {
+               rc = __tpm_pcr_read(chip, 0, digest);
+               if (rc != TPM_WARN_DOING_SELFTEST)
+                       return rc;
+               msleep(delay_msec);
+       } while (--loops > 0);
+
+       return rc;
+}
+EXPORT_SYMBOL_GPL(tpm_do_selftest);
+
 int tpm_send(u32 chip_num, void *cmd, size_t buflen)
 {
        struct tpm_chip *chip;
@@ -1005,6 +1062,46 @@ ssize_t tpm_store_cancel(struct device *dev, struct device_attribute *attr,
 }
 EXPORT_SYMBOL_GPL(tpm_store_cancel);
 
+int wait_for_tpm_stat(struct tpm_chip *chip, u8 mask, unsigned long timeout,
+                        wait_queue_head_t *queue)
+{
+       unsigned long stop;
+       long rc;
+       u8 status;
+
+       /* check current status */
+       status = chip->vendor.status(chip);
+       if ((status & mask) == mask)
+               return 0;
+
+       stop = jiffies + timeout;
+
+       if (chip->vendor.irq) {
+again:
+               timeout = stop - jiffies;
+               if ((long)timeout <= 0)
+                       return -ETIME;
+               rc = wait_event_interruptible_timeout(*queue,
+                                                     ((chip->vendor.status(chip)
+                                                     & mask) == mask),
+                                                     timeout);
+               if (rc > 0)
+                       return 0;
+               if (rc == -ERESTARTSYS && freezing(current)) {
+                       clear_thread_flag(TIF_SIGPENDING);
+                       goto again;
+               }
+       } else {
+               do {
+                       msleep(TPM_TIMEOUT);
+                       status = chip->vendor.status(chip);
+                       if ((status & mask) == mask)
+                               return 0;
+               } while (time_before(jiffies, stop));
+       }
+       return -ETIME;
+}
+EXPORT_SYMBOL_GPL(wait_for_tpm_stat);
 /*
  * Device file system interface to the TPM
  *