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From:   Cristian Marussi <cristian.marussi@arm.com>
To:     linux-kernel@vger.kernel.org, linux-arm-kernel@lists.infradead.org
Cc:     sudeep.holla@arm.com, james.quinlan@broadcom.com,
        Jonathan.Cameron@Huawei.com, f.fainelli@gmail.com,
        etienne.carriere@linaro.org, vincent.guittot@linaro.org,
        souvik.chakravarty@arm.com, wleavitt@marvell.com,
        peter.hilber@opensynergy.com, nicola.mazzucato@arm.com,
        tarek.el-sherbiny@arm.com, quic_kshivnan@quicinc.com,
        cristian.marussi@arm.com
Subject: [PATCH v4 10/11] firmware: arm_scmi: Reject SCMI drivers while in Raw mode
Date:   Wed, 19 Oct 2022 21:46:25 +0100
Message-Id: <20221019204626.3813043-11-cristian.marussi@arm.com>
In-Reply-To: <20221019204626.3813043-1-cristian.marussi@arm.com>
References: <20221019204626.3813043-1-cristian.marussi@arm.com>
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Reject SCMI driver registration when SCMI Raw mode support is configured,
so as to avoid interferences between the SCMI Raw mode transactions and the
normal SCMI stack operations.

Signed-off-by: Cristian Marussi <cristian.marussi@arm.com>
---
 drivers/firmware/arm_scmi/driver.c | 6 ++++++
 1 file changed, 6 insertions(+)

diff --git a/drivers/firmware/arm_scmi/driver.c b/drivers/firmware/arm_scmi/driver.c
index b504b5cdc55f..3e5539987443 100644
--- a/drivers/firmware/arm_scmi/driver.c
+++ b/drivers/firmware/arm_scmi/driver.c
@@ -2365,6 +2365,12 @@ int scmi_protocol_device_request(const struct scmi_device_id *id_table)
 	pr_debug("Requesting SCMI device (%s) for protocol %x\n",
 		 id_table->name, id_table->protocol_id);
 
+	if (IS_ENABLED(CONFIG_ARM_SCMI_RAW_MODE_SUPPORT)) {
+		pr_warn("SCMI Raw mode active. Rejecting '%s'/0x%02X\n",
+			id_table->name, id_table->protocol_id);
+		return -EINVAL;
+	}
+
 	/*
 	 * Search for the matching protocol rdev list and then search
 	 * of any existent equally named device...fails if any duplicate found.
-- 
2.34.1