From patchwork Tue Aug 2 15:41:28 2022 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Patryk Duda X-Patchwork-Id: 12934773 Received: from mail-lj1-f178.google.com (mail-lj1-f178.google.com [209.85.208.178]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id B774F7F for ; Tue, 2 Aug 2022 15:41:36 +0000 (UTC) Received: by mail-lj1-f178.google.com with SMTP id s14so16053440ljh.0 for ; Tue, 02 Aug 2022 08:41:36 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=semihalf.com; s=google; h=from:to:cc:subject:date:message-id:in-reply-to:references :mime-version:content-transfer-encoding; bh=3lh5+NDK8urhSXXnABP31QYe2HngTKZ+2NZLHLYtY/E=; b=VBlTac0+eLNkOx8fS58zP9Gq+9N19XfcbKIcwUGy1r6R//BvK+/12ohliAH9/U7su+ axV5laSlVYkKOuorL0lNAjkj87Wwm0T+OdWdmCjbhKNh9sI5+eocDQSfmWP1JGqOH9mW XbiU+kukMK2x/p0auilmuEN2nWoqt1Zcriq0OUYnD33TtkwnWBF8FSGd4f8ZWg71NMSS d7cyejhTVYsBVly1SyQ17qdpU9e7ZtKNyIrKPVNIqs+bJU+UZoTa8Ob+UFgHoME9ddoG 1VJKd9Hs8DbvAFjxutvDkdyXGa0s2nlziYRr0VaswnhiPy1V2FoH5ulw9y403y+Vcp0I 08ZA== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20210112; h=x-gm-message-state:from:to:cc:subject:date:message-id:in-reply-to :references:mime-version:content-transfer-encoding; bh=3lh5+NDK8urhSXXnABP31QYe2HngTKZ+2NZLHLYtY/E=; b=nVsWpnHiw0EYJKhfWUjIIHDtlswENwzNildTBFclFxHIuPzJ3qzE5HDi94Gobmz658 XL6lBiPGrbZHeavoW3tcFQU2rEMrayBlDEolCbcynfwLCLxF1wzCKftLcVRwfZH2kH7U wBNFnMfaVgbkxhNnx2MPBdT9mCrk0yx3czZgPApMqcQEXdBhZ31dYEDCctwwtSVeEVcf 5/psdlq9wHkEz5ZXOIl2MIkQA0AF5FcmR43ddnc1m8Jl+2wDSS+W7/JG2ql7OMygu1Qr FAh7Mx9UlB44wX9x1xXcNUiO8d1lyfU3OHuEurujZICM3N4uBM4d4nfz0PM5YgCp+K3y jCSA== X-Gm-Message-State: ACgBeo21jZGiTB54JPmpQppvA9mLhV+If1AGwKVOD63VzquEFm6ElnEi SZIewSZ3z2OwlNe9vTE2DVdJUQ== X-Google-Smtp-Source: AA6agR50fbfMJUJUAtcQ10ZD7qqE7NmwLXsIJJMFNvEZ9pCPJGb97G2qFcUkuhmUdZR/nH/XunNUGQ== X-Received: by 2002:a2e:a168:0:b0:25e:4dbc:2ac0 with SMTP id u8-20020a2ea168000000b0025e4dbc2ac0mr3437928ljl.187.1659454894796; Tue, 02 Aug 2022 08:41:34 -0700 (PDT) Received: from pdkmachine.office.semihalf.net ([83.142.187.84]) by smtp.gmail.com with ESMTPSA id p3-20020a2e7403000000b0025e0b9ea91csm1932193ljc.84.2022.08.02.08.41.33 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Tue, 02 Aug 2022 08:41:34 -0700 (PDT) From: Patryk Duda To: Benson Leung Cc: Guenter Roeck , Gwendal Grignou , chrome-platform@lists.linux.dev, linux-kernel@vger.kernel.org, upstream@semihalf.com, Patryk Duda Subject: [PATCH v1] platform/chrome: cros_ec_proto: Update version on GET_NEXT_EVENT failure Date: Tue, 2 Aug 2022 17:41:28 +0200 Message-Id: <20220802154128.21175-1-pdk@semihalf.com> X-Mailer: git-send-email 2.35.1 In-Reply-To: <20220714160951.9364-1-pdk@semihalf.com> References: <20220714160951.9364-1-pdk@semihalf.com> Precedence: bulk X-Mailing-List: chrome-platform@lists.linux.dev List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Some EC based devices (e.g. Fingerpint MCU) can jump to RO part of the firmware (intentionally or due to device reboot). The RO part doesn't change during the device lifecycle, so it won't support newer version of EC_CMD_GET_NEXT_EVENT command. Function cros_ec_query_all() is responsible for finding maximum supported MKBP event version. It's usually called when the device is running RW part of the firmware, so the command version can be potentially higher than version supported by the RO. The problem was fixed by updating maximum supported version when the device returns EC_RES_INVALID_VERSION (mapped to -ENOPROTOOPT). That way the kernel will use highest common version supported by RO and RW. Fixes: 3300fdd630d4 ("platform/chrome: cros_ec: handle MKBP more events flag") Cc: # 5.10+ Signed-off-by: Patryk Duda --- When Fingerprint MCU is rebooted (e.g. as a part of tests) it jumps to the RO image and performs RW image signature check. If kernel calls EC_CMD_GET_NEXT_EVENT FPMCU RO will respond with EC_RES_INVALID_VERSION because it's older than RW and supports up to version 1 of the command. As a result kernel keeps trying to get MKBP events and effectively blocks FPMCU from jumping to RW image. Before patch 3300fdd630d4 the driver called version 1 of the command. If the device responded with EC_RES_INVALID_VERSION, the driver would use version 0 of the command. Best regards, Patryk v0 -> v1 - Dropped `ver_mask` initialization. drivers/platform/chrome/cros_ec_proto.c | 32 +++++++++++++++++++++++++ 1 file changed, 32 insertions(+) diff --git a/drivers/platform/chrome/cros_ec_proto.c b/drivers/platform/chrome/cros_ec_proto.c index ff767dccdf0f..c1df8e7e48af 100644 --- a/drivers/platform/chrome/cros_ec_proto.c +++ b/drivers/platform/chrome/cros_ec_proto.c @@ -750,6 +750,7 @@ int cros_ec_get_next_event(struct cros_ec_device *ec_dev, u8 event_type; u32 host_event; int ret; + u32 ver_mask; /* * Default value for wake_event. @@ -771,6 +772,37 @@ int cros_ec_get_next_event(struct cros_ec_device *ec_dev, return get_keyboard_state_event(ec_dev); ret = get_next_event(ec_dev); + /* + * -ENOPROTOOPT is returned when EC returns EC_RES_INVALID_VERSION. + * This can occur when EC based device (e.g. Fingerprint MCU) jumps to + * the RO image which doesn't support newer version of the command. In + * this case we will attempt to update maximum supported version of the + * EC_CMD_GET_NEXT_EVENT. + */ + if (ret == -ENOPROTOOPT) { + dev_dbg(ec_dev->dev, + "GET_NEXT_EVENT returned invalid version error.\n"); + ret = cros_ec_get_host_command_version_mask(ec_dev, + EC_CMD_GET_NEXT_EVENT, + &ver_mask); + if (ret < 0 || ver_mask == 0) + /* + * Do not change the MKBP supported version if we can't + * obtain supported version correctly. Please note that + * calling EC_CMD_GET_NEXT_EVENT returned + * EC_RES_INVALID_VERSION which means that the command + * is present. + */ + return -ENOPROTOOPT; + + ec_dev->mkbp_event_supported = fls(ver_mask); + dev_dbg(ec_dev->dev, "MKBP support version changed to %u\n", + ec_dev->mkbp_event_supported - 1); + + /* Try to get next event with new MKBP support version set. */ + ret = get_next_event(ec_dev); + } + if (ret <= 0) return ret;