From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S935889Ab0CMAzx (ORCPT ); Fri, 12 Mar 2010 19:55:53 -0500 Received: from kroah.org ([198.145.64.141]:46908 "EHLO coco.kroah.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S935414Ab0CMAba (ORCPT ); Fri, 12 Mar 2010 19:31:30 -0500 X-Mailbox-Line: From gregkh@kvm.kroah.org Fri Mar 12 16:27:10 2010 Message-Id: <20100313002709.946796447@kvm.kroah.org> User-Agent: quilt/0.48-4.4 Date: Fri, 12 Mar 2010 16:26:27 -0800 From: Greg KH To: linux-kernel@vger.kernel.org, stable@kernel.org Cc: stable-review@kernel.org, torvalds@linux-foundation.org, akpm@linux-foundation.org, alan@lxorguk.ukuu.org.uk, Rajiv Andrade , Eric Paris , James Morris Subject: [054/145] tpm_tis: TPM_STS_DATA_EXPECT workaround In-Reply-To: <20100313002816.GA18903@kroah.com> Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org 2.6.32-stable review patch. If anyone has any objections, please let me know. ---------------- From: Rajiv Andrade commit 3507d612366a4e81226295f646410130a1f62a5c upstream. Some newer Lenovo models are shipped with a TPM that doesn't seem to set the TPM_STS_DATA_EXPECT status bit when sending it a burst of data, so the code understands it as a failure and doesn't proceed sending the chip the intended data. In this patch we bypass this bit check in case the itpm module parameter was set. This patch is based on Andy Isaacson's one: http://marc.info/?l=linux-kernel&m=124650185023495&w=2 It was heavily discussed how should we deal with identifying the chip in kernel space, but the required patch to do so was NACK'd: http://marc.info/?l=linux-kernel&m=124650186423711&w=2 This way we let the user choose using this workaround or not based on his observations on this code behavior when trying to use the TPM. Fixed a checkpatch issue present on the previous patch, thanks to Daniel Walker. Signed-off-by: Rajiv Andrade Acked-by: Eric Paris Tested-by: Seiji Munetoh Signed-off-by: James Morris Signed-off-by: Greg Kroah-Hartman --- drivers/char/tpm/tpm_tis.c | 10 +++++++++- 1 file changed, 9 insertions(+), 1 deletion(-) --- a/drivers/char/tpm/tpm_tis.c +++ b/drivers/char/tpm/tpm_tis.c @@ -257,6 +257,10 @@ out: return size; } +static int itpm; +module_param(itpm, bool, 0444); +MODULE_PARM_DESC(itpm, "Force iTPM workarounds (found on some Lenovo laptops)"); + /* * If interrupts are used (signaled by an irq set in the vendor structure) * tpm.c can skip polling for the data to be available as the interrupt is @@ -293,7 +297,7 @@ static int tpm_tis_send(struct tpm_chip wait_for_stat(chip, TPM_STS_VALID, chip->vendor.timeout_c, &chip->vendor.int_queue); status = tpm_tis_status(chip); - if ((status & TPM_STS_DATA_EXPECT) == 0) { + if (!itpm && (status & TPM_STS_DATA_EXPECT) == 0) { rc = -EIO; goto out_err; } @@ -467,6 +471,10 @@ static int tpm_tis_init(struct device *d "1.2 TPM (device-id 0x%X, rev-id %d)\n", vendor >> 16, ioread8(chip->vendor.iobase + TPM_RID(0))); + if (itpm) + dev_info(dev, "Intel iTPM workaround enabled\n"); + + /* Figure out the capabilities */ intfcaps = ioread32(chip->vendor.iobase +