/**
* tpm_calc_ordinal_duration() - calculate the maximum command duration
* @chip: TPM chip to use.
* @ordinal: TPM command ordinal.
*
* The function returns the maximum amount of time the chip could take
* to return the result for a particular ordinal in jiffies.
*
* Return: A maximal duration time for an ordinal in jiffies.
*/
unsigned long tpm_calc_ordinal_duration(struct tpm_chip *chip, u32 ordinal)
{
if (chip->flags & TPM_CHIP_FLAG_TPM2)
return tpm2_calc_ordinal_duration(chip, ordinal);
else
return tpm1_calc_ordinal_duration(chip, ordinal);
}
/*
* Internal kernel interface to transmit TPM commands
*/
ssize_t tpm_transmit(struct tpm_chip *chip, const u8 *buf, size_t bufsiz,
unsigned int flags)
{
ssize_t rc;
u32 count, ordinal;
unsigned long stop;
if (bufsiz < TPM_HEADER_SIZE)
return -EINVAL;
if (bufsiz > TPM_BUFSIZE)
bufsiz = TPM_BUFSIZE;
count = be32_to_cpu(*((__be32 *) (buf + 2)));
ordinal = be32_to_cpu(*((__be32 *) (buf + 6)));
if (count == 0)
return -ENODATA;
if (count > bufsiz) {
dev_err(&chip->dev,
"invalid count value %x %zx\n", count, bufsiz);
return -E2BIG;
}
if (!(flags & TPM_TRANSMIT_UNLOCKED))
mutex_lock(&chip->tpm_mutex);
rc = chip->ops->send(chip, (u8 *) buf, count);
if (rc < 0) {
dev_err(&chip->dev,
"tpm_transmit: tpm_send: error %zd\n", rc);
goto out;
}
if (chip->flags & TPM_CHIP_FLAG_IRQ)
goto out_recv;
if (chip->flags & TPM_CHIP_FLAG_TPM2)
stop = jiffies + tpm2_calc_ordinal_duration(chip, ordinal);
else
stop = jiffies + tpm_calc_ordinal_duration(chip, ordinal);
do {
u8 status = chip->ops->status(chip);
if ((status & chip->ops->req_complete_mask) ==
chip->ops->req_complete_val)
goto out_recv;
if (chip->ops->req_canceled(chip, status)) {
dev_err(&chip->dev, "Operation Canceled\n");
rc = -ECANCELED;
goto out;
}
msleep(TPM_TIMEOUT); /* CHECK */
rmb();
} while (time_before(jiffies, stop));
chip->ops->cancel(chip);
dev_err(&chip->dev, "Operation Timed out\n");
rc = -ETIME;
goto out;
out_recv:
rc = chip->ops->recv(chip, (u8 *) buf, bufsiz);
if (rc < 0)
dev_err(&chip->dev,
"tpm_transmit: tpm_recv: error %zd\n", rc);
out:
if (!(flags & TPM_TRANSMIT_UNLOCKED))
mutex_unlock(&chip->tpm_mutex);
return rc;
}
