From mboxrd@z Thu Jan 1 00:00:00 1970 From: Jarkko Sakkinen Subject: Re: [PATCH v8 3/7] tpm_tis: Introduce intermediate layer for TPM access Date: Tue, 24 May 2016 00:20:09 +0300 Message-ID: <20160523212009.GA30456@intel.com> References: <1463610953-2766-1-git-send-email-christophe-h.ricard@st.com> <1463610953-2766-4-git-send-email-christophe-h.ricard@st.com> Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Return-path: Content-Disposition: inline In-Reply-To: <1463610953-2766-4-git-send-email-christophe-h.ricard-qxv4g6HH51o@public.gmane.org> List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: tpmdd-devel-bounces-5NWGOfrQmneRv+LV9MX5uipxlwaOVQ5f@public.gmane.org To: Christophe Ricard Cc: jean-luc.blanc-qxv4g6HH51o@public.gmane.org, ashley-fm2HMyfA2y6tG0bUXCXiUA@public.gmane.org, linux-security-module-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, tpmdd-devel-5NWGOfrQmneRv+LV9MX5uipxlwaOVQ5f@public.gmane.org, christophe-h.ricard-qxv4g6HH51o@public.gmane.org, benoit.houyere-qxv4g6HH51o@public.gmane.org List-Id: tpmdd-devel@lists.sourceforge.net On Thu, May 19, 2016 at 12:35:49AM +0200, Christophe Ricard wrote: > From: Christophe Ricard > > This splits tpm_tis in a high-level protocol part and a low-level interface > for the actual TPM communication. The low-level interface can then be > implemented by additional drivers to provide access to TPMs using other > mechanisms, for example native I2C or SPI transfers, while still reusing > the same TIS protocol implementation. > > Though the ioread/iowrite calls cannot fail, other implementations of this > interface might want to return error codes if their communication fails. > > This follows the usual pattern of negative values representing errors and > zero representing success. Positive values are not used (yet). > > Errors are passed back to the caller if possible. If the interface of a > function does not allow that, it tries to do the most sensible thing it > can, but this might also mean ignoring the error in this instance. > > Signed-off-by: Alexander Steffen > Signed-off-by: Christophe Ricard Reviewed-by: Jarkko Sakkinen /Jarkko ------------------------------------------------------------------------------ Mobile security can be enabling, not merely restricting. Employees who bring their own devices (BYOD) to work are irked by the imposition of MDM restrictions. Mobile Device Manager Plus allows you to control only the apps on BYO-devices by containerizing them, leaving personal data untouched! https://ad.doubleclick.net/ddm/clk/304595813;131938128;j