linux-kernel - [PATCH v2] i2c: i2c-cadence: Initialize configuration before probing devices

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [thread-next>] [day] [month] [year] [list]

Message-Id: <1484578178-3165-1-git-send-email-mike.looijmans@topic.nl>
Date:   Mon, 16 Jan 2017 15:49:38 +0100
From:   Mike Looijmans <mike.looijmans@...ic.nl>
To:     linux-i2c@...r.kernel.org
Cc:     linux-arm-kernel@...ts.infradead.org, linux-kernel@...r.kernel.org,
        wsa@...-dreams.de, soren.brinkmann@...inx.com,
        michal.simek@...inx.com, Mike Looijmans <mike.looijmans@...ic.nl>
Subject: [PATCH v2] i2c: i2c-cadence: Initialize configuration before probing devices

The cadence I2C driver calls cdns_i2c_writereg(..) to setup a workaround
in the controller, but did so after calling i2c_add_adapter() which starts
probing devices on the bus. Change the order so that the configuration is
completely finished before using the adapter.

Signed-off-by: Mike Looijmans <mike.looijmans@...ic.nl>
---
v2: Only move the initialization to before i2c_add_adapter, don't change the
    logging output.
 drivers/i2c/busses/i2c-cadence.c | 8 ++++----
 1 file changed, 4 insertions(+), 4 deletions(-)

diff --git a/drivers/i2c/busses/i2c-cadence.c b/drivers/i2c/busses/i2c-cadence.c
index 6869712..45d6771 100644
--- a/drivers/i2c/busses/i2c-cadence.c
+++ b/drivers/i2c/busses/i2c-cadence.c
@@ -962,10 +962,6 @@ static int cdns_i2c_probe(struct platform_device *pdev)
 		goto err_clk_dis;
 	}
 
-	ret = i2c_add_adapter(&id->adap);
-	if (ret < 0)
-		goto err_clk_dis;
-
 	/*
 	 * Cadence I2C controller has a bug wherein it generates
 	 * invalid read transaction after HW timeout in master receiver mode.
@@ -975,6 +971,10 @@ static int cdns_i2c_probe(struct platform_device *pdev)
 	 */
 	cdns_i2c_writereg(CDNS_I2C_TIMEOUT_MAX, CDNS_I2C_TIME_OUT_OFFSET);
 
+	ret = i2c_add_adapter(&id->adap);
+	if (ret < 0)
+		goto err_clk_dis;
+
 	dev_info(&pdev->dev, "%u kHz mmio %08lx irq %d\n",
 		 id->i2c_clk / 1000, (unsigned long)r_mem->start, id->irq);
 
-- 
1.9.1