diff options
Diffstat (limited to 'drivers/char/tpm/tpm.c')
| -rw-r--r-- | drivers/char/tpm/tpm.c | 41 |
1 files changed, 41 insertions, 0 deletions
diff --git a/drivers/char/tpm/tpm.c b/drivers/char/tpm/tpm.c index 2e12b3f9813..efd24bbb5cb 100644 --- a/drivers/char/tpm/tpm.c +++ b/drivers/char/tpm/tpm.c @@ -27,6 +27,7 @@ #include <linux/slab.h> #include <linux/mutex.h> #include <linux/spinlock.h> +#include <linux/freezer.h> #include "tpm.h" @@ -1057,6 +1058,46 @@ 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 * |