From patchwork Sun Jan 1 20:14:00 2017 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Hans de Goede X-Patchwork-Id: 710063 Return-Path: X-Original-To: incoming@patchwork.ozlabs.org Delivered-To: patchwork-incoming@bilbo.ozlabs.org Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by ozlabs.org (Postfix) with ESMTP id 3tsBHm28hzz9s65 for ; Mon, 2 Jan 2017 07:14:12 +1100 (AEDT) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S932365AbdAAUOJ (ORCPT ); Sun, 1 Jan 2017 15:14:09 -0500 Received: from mx1.redhat.com ([209.132.183.28]:47500 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S932229AbdAAUOJ (ORCPT ); Sun, 1 Jan 2017 15:14:09 -0500 Received: from int-mx14.intmail.prod.int.phx2.redhat.com (int-mx14.intmail.prod.int.phx2.redhat.com [10.5.11.27]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mx1.redhat.com (Postfix) with ESMTPS id D7F6C81239; Sun, 1 Jan 2017 20:14:09 +0000 (UTC) Received: from shalem.localdomain.com (vpn1-7-169.ams2.redhat.com [10.36.7.169]) by int-mx14.intmail.prod.int.phx2.redhat.com (8.14.4/8.14.4) with ESMTP id v01KE5Hk015468; Sun, 1 Jan 2017 15:14:08 -0500 From: Hans de Goede To: Jarkko Nikula , Len Brown Cc: Jani Nikula , =?UTF-8?q?Ville=20Syrj=C3=A4l=C3=A4?= , "russianneuromancer @ ya . ru" , linux-i2c@vger.kernel.org, intel-gfx , Hans de Goede Subject: [RFC 1/4] x86/platform/intel/iosf_mbi: Add a mutex for punit access Date: Sun, 1 Jan 2017 21:14:00 +0100 Message-Id: <20170101201403.12132-2-hdegoede@redhat.com> In-Reply-To: <20170101201403.12132-1-hdegoede@redhat.com> References: <20170101201403.12132-1-hdegoede@redhat.com> X-Scanned-By: MIMEDefang 2.68 on 10.5.11.27 X-Greylist: Sender IP whitelisted, not delayed by milter-greylist-4.5.16 (mx1.redhat.com [10.5.110.25]); Sun, 01 Jan 2017 20:14:09 +0000 (UTC) Sender: linux-i2c-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-i2c@vger.kernel.org The punit on baytrail / cherrytrail systems is not only accessed through the iosf_mbi functions, but also by the i915 code. Add a mutex to protect the punit against simultaneous accesses and 2 functions to lock / unlock this mutex. Signed-off-by: Hans de Goede --- arch/x86/include/asm/iosf_mbi.h | 19 +++++++++++++++++++ arch/x86/platform/intel/iosf_mbi.c | 13 +++++++++++++ 2 files changed, 32 insertions(+) diff --git a/arch/x86/include/asm/iosf_mbi.h b/arch/x86/include/asm/iosf_mbi.h index b41ee16..02963bd 100644 --- a/arch/x86/include/asm/iosf_mbi.h +++ b/arch/x86/include/asm/iosf_mbi.h @@ -88,6 +88,21 @@ int iosf_mbi_write(u8 port, u8 opcode, u32 offset, u32 mdr); */ int iosf_mbi_modify(u8 port, u8 opcode, u32 offset, u32 mdr, u32 mask); +/** + * iosf_mbi_punit_lock() - Lock the punit mutex + * + * This function must be called before accessing the punit or the pmic, be it + * through iosf_mbi_* or through other means. + * + * This function locks a mutex, as such it may sleep. + */ +void iosf_mbi_punit_lock(void); + +/** + * iosf_mbi_punit_unlock() - Unlock the punit mutex + */ +void iosf_mbi_punit_unlock(void); + #else /* CONFIG_IOSF_MBI is not enabled */ static inline bool iosf_mbi_available(void) @@ -115,6 +130,10 @@ int iosf_mbi_modify(u8 port, u8 opcode, u32 offset, u32 mdr, u32 mask) WARN(1, "IOSF_MBI driver not available"); return -EPERM; } + +static inline void iosf_mbi_punit_lock(void) {} +static inline void iosf_mbi_punit_unlock(void) {} + #endif /* CONFIG_IOSF_MBI */ #endif /* IOSF_MBI_SYMS_H */ diff --git a/arch/x86/platform/intel/iosf_mbi.c b/arch/x86/platform/intel/iosf_mbi.c index edf2c54..75d8135 100644 --- a/arch/x86/platform/intel/iosf_mbi.c +++ b/arch/x86/platform/intel/iosf_mbi.c @@ -34,6 +34,7 @@ static struct pci_dev *mbi_pdev; static DEFINE_SPINLOCK(iosf_mbi_lock); +static DEFINE_MUTEX(iosf_mbi_punit_mutex); static inline u32 iosf_mbi_form_mcr(u8 op, u8 port, u8 offset) { @@ -190,6 +191,18 @@ bool iosf_mbi_available(void) } EXPORT_SYMBOL(iosf_mbi_available); +void iosf_mbi_punit_lock(void) +{ + mutex_lock(&iosf_mbi_punit_mutex); +} +EXPORT_SYMBOL(iosf_mbi_punit_lock); + +void iosf_mbi_punit_unlock(void) +{ + mutex_unlock(&iosf_mbi_punit_mutex); +} +EXPORT_SYMBOL(iosf_mbi_punit_unlock); + #ifdef CONFIG_IOSF_MBI_DEBUG static u32 dbg_mdr; static u32 dbg_mcr;