linux-kernel - Re: [PATCH 3/3] [media] cx231xx: only unregister successfully registered i2c adapters

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Date:   Wed, 9 Aug 2017 11:27:41 -0300
From:   Mauro Carvalho Chehab <mchehab@...pensource.com>
To:     Peter Rosin <peda@...ntia.se>
Cc:     linux-kernel@...r.kernel.org,
        Mauro Carvalho Chehab <mchehab@...nel.org>,
        linux-media@...r.kernel.org
Subject: Re: [PATCH 3/3] [media] cx231xx: only unregister successfully
 registered i2c adapters

Em Mon, 31 Jul 2017 15:38:52 +0200
Peter Rosin <peda@...ntia.se> escreveu:

> This prevents potentially scary debug messages from the i2c core.
> 
> Signed-off-by: Peter Rosin <peda@...ntia.se>
> ---
>  drivers/media/usb/cx231xx/cx231xx-core.c | 3 +++
>  drivers/media/usb/cx231xx/cx231xx-i2c.c  | 3 ++-
>  2 files changed, 5 insertions(+), 1 deletion(-)
> 
> diff --git a/drivers/media/usb/cx231xx/cx231xx-core.c b/drivers/media/usb/cx231xx/cx231xx-core.c
> index 46646ecd2dbc..f372ad3917a8 100644
> --- a/drivers/media/usb/cx231xx/cx231xx-core.c
> +++ b/drivers/media/usb/cx231xx/cx231xx-core.c
> @@ -1311,6 +1311,7 @@ int cx231xx_dev_init(struct cx231xx *dev)
>  	dev->i2c_bus[0].i2c_period = I2C_SPEED_100K;	/* 100 KHz */
>  	dev->i2c_bus[0].i2c_nostop = 0;
>  	dev->i2c_bus[0].i2c_reserve = 0;
> +	dev->i2c_bus[0].i2c_rc = -ENODEV;
>  
>  	/* External Master 2 Bus */
>  	dev->i2c_bus[1].nr = 1;
> @@ -1318,6 +1319,7 @@ int cx231xx_dev_init(struct cx231xx *dev)
>  	dev->i2c_bus[1].i2c_period = I2C_SPEED_100K;	/* 100 KHz */
>  	dev->i2c_bus[1].i2c_nostop = 0;
>  	dev->i2c_bus[1].i2c_reserve = 0;
> +	dev->i2c_bus[1].i2c_rc = -ENODEV;
>  
>  	/* Internal Master 3 Bus */
>  	dev->i2c_bus[2].nr = 2;
> @@ -1325,6 +1327,7 @@ int cx231xx_dev_init(struct cx231xx *dev)
>  	dev->i2c_bus[2].i2c_period = I2C_SPEED_100K;	/* 100kHz */
>  	dev->i2c_bus[2].i2c_nostop = 0;
>  	dev->i2c_bus[2].i2c_reserve = 0;
> +	dev->i2c_bus[2].i2c_rc = -ENODEV;
>  
>  	/* register I2C buses */
>  	errCode = cx231xx_i2c_register(&dev->i2c_bus[0]);
> diff --git a/drivers/media/usb/cx231xx/cx231xx-i2c.c b/drivers/media/usb/cx231xx/cx231xx-i2c.c
> index 3e49517cb5e0..8ce6b815d16d 100644
> --- a/drivers/media/usb/cx231xx/cx231xx-i2c.c
> +++ b/drivers/media/usb/cx231xx/cx231xx-i2c.c
> @@ -553,7 +553,8 @@ int cx231xx_i2c_register(struct cx231xx_i2c *bus)
>   */
>  void cx231xx_i2c_unregister(struct cx231xx_i2c *bus)
>  {
> -	i2c_del_adapter(&bus->i2c_adap);
> +	if (!bus->i2c_rc)
> +		i2c_del_adapter(&bus->i2c_adap);

That doesn't sound right. what happens if i2c_rc is 1 or 2?

IMHO, the right would would be, instead:

	if (bus->i2c_rc >= 0)
		i2c_del_adapter(&bus->i2c_adap);

Regards

Thanks,
Mauro