This is a note to let you know that I've just added the patch titled
tpm_tis_spi: Check correct byte for wait state indicator
to the 4.9-stable tree which can be found at:
http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary
The filename of the patch is:
tpm_tis_spi-check-correct-byte-for-wait-state-indicator.patch
and it can be found in the queue-4.9 subdirectory.
If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@xxxxxxxxxxxxxxx> know about it.
>From e110cc69dc2ad679d6d478df636b99b14e6fbbc9 Mon Sep 17 00:00:00 2001
From: Peter Huewe <peter.huewe@xxxxxxxxxxxx>
Date: Thu, 2 Mar 2017 13:03:13 +0000
Subject: tpm_tis_spi: Check correct byte for wait state indicator
From: Peter Huewe <peter.huewe@xxxxxxxxxxxx>
commit e110cc69dc2ad679d6d478df636b99b14e6fbbc9 upstream.
Wait states are signaled in the last byte received from the TPM in
response to the header, not the first byte. Check rx_buf[3] instead of
rx_buf[0].
Fixes: 0edbfea537d1 ("tpm/tpm_tis_spi: Add support for spi phy")
Signed-off-by: Alexander Steffen <Alexander.Steffen@xxxxxxxxxxxx>
Signed-off-by: Peter Huewe <peter.huewe@xxxxxxxxxxxx>
Reviewed-by: Jarkko Sakkinen <jarkko.sakkinen@xxxxxxxxxxxxxxx>
Tested-by: Benoit Houyere <benoit.houyere@xxxxxx>
Signed-off-by: Jarkko Sakkinen <jarkko.sakkinen@xxxxxxxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
---
drivers/char/tpm/tpm_tis_spi.c | 34 +++++++++++++++++-----------------
1 file changed, 17 insertions(+), 17 deletions(-)
--- a/drivers/char/tpm/tpm_tis_spi.c
+++ b/drivers/char/tpm/tpm_tis_spi.c
@@ -86,25 +86,25 @@ static int tpm_tis_spi_transfer(struct t
if (ret < 0)
goto exit;
- phy->tx_buf[0] = 0;
+ if ((phy->rx_buf[3] & 0x01) == 0) {
+ // handle SPI wait states
+ phy->tx_buf[0] = 0;
- /* According to TCG PTP specification, if there is no TPM present at
- * all, then the design has a weak pull-up on MISO. If a TPM is not
- * present, a pull-up on MISO means that the SB controller sees a 1,
- * and will latch in 0xFF on the read.
- */
- for (i = 0; (phy->rx_buf[0] & 0x01) == 0 && i < TPM_RETRY; i++) {
- spi_xfer.len = 1;
- spi_message_init(&m);
- spi_message_add_tail(&spi_xfer, &m);
- ret = spi_sync_locked(phy->spi_device, &m);
- if (ret < 0)
- goto exit;
- }
+ for (i = 0; i < TPM_RETRY; i++) {
+ spi_xfer.len = 1;
+ spi_message_init(&m);
+ spi_message_add_tail(&spi_xfer, &m);
+ ret = spi_sync_locked(phy->spi_device, &m);
+ if (ret < 0)
+ goto exit;
+ if (phy->rx_buf[0] & 0x01)
+ break;
+ }
- if (i == TPM_RETRY) {
- ret = -ETIMEDOUT;
- goto exit;
+ if (i == TPM_RETRY) {
+ ret = -ETIMEDOUT;
+ goto exit;
+ }
}
spi_xfer.cs_change = 0;
Patches currently in stable-queue which might be from peter.huewe@xxxxxxxxxxxx are
queue-4.9/tpm_tis_spi-abort-transfer-when-too-many-wait-states-are-signaled.patch
queue-4.9/tpm_tis_spi-remove-limitation-of-transfers-to-max_spi_framesize-bytes.patch
queue-4.9/tpm_tis_core-choose-appropriate-timeout-for-reading-burstcount.patch
queue-4.9/tpm_tis_spi-add-small-delay-after-last-transfer.patch
queue-4.9/tpm_tis_spi-check-correct-byte-for-wait-state-indicator.patch
queue-4.9/tpm_tis_spi-use-single-function-to-transfer-data.patch