From 888d867df4417deffc33927e6fc2c6925736fe92 Mon Sep 17 00:00:00 2001 From: Tomas Winkler Date: Mon, 5 Mar 2018 13:34:49 +0200 Subject: tpm: cmd_ready command can be issued only after granting locality The correct sequence is to first request locality and only after that perform cmd_ready handshake, otherwise the hardware will drop the subsequent message as from the device point of view the cmd_ready handshake wasn't performed. Symmetrically locality has to be relinquished only after going idle handshake has completed, this requires that go_idle has to poll for the completion and as well locality relinquish has to poll for completion so it is not overridden in back to back commands flow. Two wrapper functions are added (request_locality relinquish_locality) to simplify the error handling. The issue is only visible on devices that support multiple localities. Fixes: 877c57d0d0ca ("tpm_crb: request and relinquish locality 0") Signed-off-by: Tomas Winkler Reviewed-by: Jarkko Sakkinen Tested-by: Jarkko Sakkinen Signed-off-by: Jarkko Sakkinen --- include/linux/tpm.h | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) (limited to 'include/linux/tpm.h') diff --git a/include/linux/tpm.h b/include/linux/tpm.h index bcdd3790e94d..06639fb6ab85 100644 --- a/include/linux/tpm.h +++ b/include/linux/tpm.h @@ -44,7 +44,7 @@ struct tpm_class_ops { bool (*update_timeouts)(struct tpm_chip *chip, unsigned long *timeout_cap); int (*request_locality)(struct tpm_chip *chip, int loc); - void (*relinquish_locality)(struct tpm_chip *chip, int loc); + int (*relinquish_locality)(struct tpm_chip *chip, int loc); void (*clk_enable)(struct tpm_chip *chip, bool value); }; -- cgit