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From: Peter Korsgaard <peter@korsgaard.com>
To: Grygorii Tertychnyi <grembeter@gmail.com>
Cc: Andrew Lunn <andrew@lunn.ch>,  Thomas Gleixner <tglx@linutronix.de>,
  linux-i2c@vger.kernel.org,  linux-kernel@vger.kernel.org,
  bsp-development.geo@leica-geosystems.com,  Grygorii Tertychnyi
 <grygorii.tertychnyi@leica-geosystems.com>
Subject: Re: [PATCH] i2c: ocores: set IACK bit after core is enabled
References: <20240517191000.11390-1-grygorii.tertychnyi@leica-geosystems.com>
Date: Sat, 18 May 2024 20:46:12 +0200
In-Reply-To: <20240517191000.11390-1-grygorii.tertychnyi@leica-geosystems.com>
	(Grygorii Tertychnyi's message of "Fri, 17 May 2024 21:10:00 +0200")
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>>>>> "Grygorii" == Grygorii Tertychnyi <grembeter@gmail.com> writes:

 > Setting IACK bit when core is disabled does not clear the "Interrupt Flag"
 > bit in the status register, and the interrupt remains pending.

 > Sometimes it causes failure for the very first message transfer, that is
 > usually a device probe.

 > Hence, set IACK bit after core is enabled to clear pending interrupt.

 > Signed-off-by: Grygorii Tertychnyi <grygorii.tertychnyi@leica-geosystems.com>

I no longer have access to a device with i2c-ocores, but it sounds
sensible so:

Acked-by: Peter Korsgaard <peter@korsgaard.com>


> ---
 >  drivers/i2c/busses/i2c-ocores.c | 2 +-
 >  1 file changed, 1 insertion(+), 1 deletion(-)

 > diff --git a/drivers/i2c/busses/i2c-ocores.c b/drivers/i2c/busses/i2c-ocores.c
 > index a0af027db04c..a52f8fd4e2fe 100644
 > --- a/drivers/i2c/busses/i2c-ocores.c
 > +++ b/drivers/i2c/busses/i2c-ocores.c
 > @@ -439,8 +439,8 @@ static int ocores_init(struct device *dev, struct ocores_i2c *i2c)
 >  	oc_setreg(i2c, OCI2C_PREHIGH, prescale >> 8);

 >  	/* Init the device */
 > -	oc_setreg(i2c, OCI2C_CMD, OCI2C_CMD_IACK);
 >  	oc_setreg(i2c, OCI2C_CONTROL, ctrl | OCI2C_CTRL_EN);
 > +	oc_setreg(i2c, OCI2C_CMD, OCI2C_CMD_IACK);

 >  	return 0;
 >  }
 > --
 > 2.43.0

-- 
Bye, Peter Korsgaard