[PATCH v2 3/5] tpm: migrate tpm2_probe() to use struct tpm_buf

From: Jarkko Sakkinen
Date: Mon Mar 05 2018 - 09:39:49 EST


In order to make struct tpm_buf the first class object for constructing TPM
commands, migrate tpm2_probe() to use it.

Signed-off-by: Jarkko Sakkinen <jarkko.sakkinen@xxxxxxxxxxxxxxx>
---
drivers/char/tpm/tpm2-cmd.c | 27 +++++++++++++++------------
1 file changed, 15 insertions(+), 12 deletions(-)

diff --git a/drivers/char/tpm/tpm2-cmd.c b/drivers/char/tpm/tpm2-cmd.c
index abe6ef4a7a0b..890d83c5c78b 100644
--- a/drivers/char/tpm/tpm2-cmd.c
+++ b/drivers/char/tpm/tpm2-cmd.c
@@ -851,22 +851,25 @@ static int tpm2_do_selftest(struct tpm_chip *chip)
*/
int tpm2_probe(struct tpm_chip *chip)
{
- struct tpm2_cmd cmd;
+ struct tpm_output_header *out;
+ struct tpm_buf buf;
int rc;

- cmd.header.in = tpm2_get_tpm_pt_header;
- cmd.params.get_tpm_pt_in.cap_id = cpu_to_be32(TPM2_CAP_TPM_PROPERTIES);
- cmd.params.get_tpm_pt_in.property_id = cpu_to_be32(0x100);
- cmd.params.get_tpm_pt_in.property_cnt = cpu_to_be32(1);
-
- rc = tpm_transmit_cmd(chip, NULL, &cmd, sizeof(cmd), 0, 0, NULL);
- if (rc < 0)
+ rc = tpm_buf_init(&buf, TPM2_ST_NO_SESSIONS, TPM2_CC_GET_CAPABILITY);
+ if (rc)
return rc;
-
- if (be16_to_cpu(cmd.header.out.tag) == TPM2_ST_NO_SESSIONS)
+ tpm_buf_append_u32(&buf, TPM2_CAP_TPM_PROPERTIES);
+ tpm_buf_append_u32(&buf, TPM_PT_TOTAL_COMMANDS);
+ tpm_buf_append_u32(&buf, 1);
+ rc = tpm_transmit_cmd(chip, NULL, buf.data, PAGE_SIZE, 0, 0, NULL);
+ if (rc < 0)
+ goto out;
+ out = (struct tpm_output_header *)buf.data;
+ if (be16_to_cpu(out->tag) == TPM2_ST_NO_SESSIONS)
chip->flags |= TPM_CHIP_FLAG_TPM2;
-
- return 0;
+out:
+ tpm_buf_destroy(&buf);
+ return rc;
}
EXPORT_SYMBOL_GPL(tpm2_probe);

--
2.15.1