linux-kernel - [PATCH v2 1/4] i2c: check bus number property in DesignWare I2C Controller

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

Message-Id: <20211005143748.2471647-2-pan@semihalf.com>
Date:   Tue,  5 Oct 2021 16:37:45 +0200
From:   Paweł Anikiel <pan@...ihalf.com>
To:     jarkko.nikula@...ux.intel.com, andriy.shevchenko@...ux.intel.com,
        mika.westerberg@...ux.intel.com, robh+dt@...nel.org,
        p.zabel@...gutronix.de, arnd@...db.de, olof@...om.net,
        soc@...nel.org, dinguyen@...nel.org, p.yadav@...com,
        Tudor.Ambarus@...rochip.com
Cc:     linux-i2c@...r.kernel.org, linux-kernel@...r.kernel.org,
        alexandre.belloni@...tlin.com, sre@...nel.org,
        thunder.leizhen@...wei.com, Jonathan.Cameron@...wei.com,
        devicetree@...r.kernel.org, linux-arm-kernel@...ts.infradead.org,
        ka@...ihalf.com, tn@...ihalf.com, jam@...ihalf.com,
        amstan@...gle.com,
        Paweł Anikiel <pan@...ihalf.com>
Subject: [PATCH v2 1/4] i2c: check bus number property in DesignWare I2C Controller

On SoCFPGA systems, it's desireable to have fixed numbering for
i2c busses, while being able to enable/disable them (e.g. have i2c1
be mapped to /dev/i2c-1, even though i2c0 is disabled). This can also
be achieved using devicetree aliases (see i2c_add_adapter). However,
having the driver be self-contained without relying on aliases is more
robust.

Signed-off-by: Paweł Anikiel <pan@...ihalf.com>
---
 drivers/i2c/busses/i2c-designware-platdrv.c | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/drivers/i2c/busses/i2c-designware-platdrv.c b/drivers/i2c/busses/i2c-designware-platdrv.c
index 21113665ddea..f27e6bc9ad9d 100644
--- a/drivers/i2c/busses/i2c-designware-platdrv.c
+++ b/drivers/i2c/busses/i2c-designware-platdrv.c
@@ -280,7 +280,8 @@ static int dw_i2c_plat_probe(struct platform_device *pdev)
 					I2C_CLASS_HWMON : I2C_CLASS_DEPRECATED;
 	ACPI_COMPANION_SET(&adap->dev, ACPI_COMPANION(&pdev->dev));
 	adap->dev.of_node = pdev->dev.of_node;
-	adap->nr = -1;
+	if (of_property_read_u32(pdev->dev.of_node, "busno", &adap->nr))
+		adap->nr = -1;
 
 	if (dev->flags & ACCESS_NO_IRQ_SUSPEND) {
 		dev_pm_set_driver_flags(&pdev->dev,
-- 
2.25.1