From: valdis.kletnieks@vt.edu (valdis.kletnieks at vt.edu)
To: kernelnewbies@lists.kernelnewbies.org
Subject: probe gets called without i2c device
Date: Fri, 23 Mar 2018 10:59:37 -0400 [thread overview]
Message-ID: <5098.1521817177@turing-police.cc.vt.edu> (raw)
In-Reply-To: <16253144a05.100dc7ca7395558.6836327520939081040@iqroottech.com>
On Fri, 23 Mar 2018 19:07:41 +0530, MUHAMMED ASAD P T said:
> We have the device tree information and wrote in the board. In this device
> tree, we specify our I2c device details.
So you told the kernel the device is there.
> In usual, if the device is there, then driver probe gets called. This is the proper scenario.
So the kernel acts like it's there.
> But if the device is not there, then i2c master controller will not get the
> Ack from slave device. Still driver probe gets called without device
> connected (In device tree, device node is there for slave device).
Why is the slave listed if it isn't actually present and wired up?
> How the driver probe gets called?? This is the problem for us.
Maybe if you don't want the driver called if the device isn't there, you
shouldn't lie to the kernel and write a device tree entry that says it *is*
there.
Just a thought...
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next prev parent reply other threads:[~2018-03-23 14:59 UTC|newest]
Thread overview: 5+ messages / expand[flat|nested] mbox.gz Atom feed top
2018-03-23 12:17 probe gets called without i2c device MUHAMMED ASAD P T
2018-03-23 12:27 ` Greg KH
2018-03-23 13:37 ` MUHAMMED ASAD P T
2018-03-23 14:59 ` valdis.kletnieks at vt.edu [this message]
-- strict thread matches above, loose matches on Subject: below --
2018-03-23 7:19 MUHAMMED ASAD P T
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