Re: [PATCH 3/3] i2c-piix4: Pre-shift the port number

[Mika Westerberg <mika.westerberg@linux.intel.com>]

On Fri, Jan 29, 2016 at 10:46:37AM +0100, Jean Delvare wrote:
> Shift the port number at initialization time, so that it is ready to
> use at run time. That way we don't have to do it again for every SMBus
> transaction.
> 
> Signed-off-by: Jean Delvare <jdelvare@suse.de>
> Cc: Mika Westerberg <mika.westerberg@linux.intel.com>
> Cc: Christian Fetzer <fetzer.ch@gmail.com>
> Cc: Wolfram Sang <wsa@the-dreams.de>
> ---
>  drivers/i2c/busses/i2c-piix4.c |   10 +++++-----
>  1 file changed, 5 insertions(+), 5 deletions(-)
> 
> --- linux-4.5-rc0.orig/drivers/i2c/busses/i2c-piix4.c	2016-01-29 07:57:13.706365999 +0100
> +++ linux-4.5-rc0/drivers/i2c/busses/i2c-piix4.c	2016-01-29 10:38:34.720453729 +0100
> @@ -158,7 +158,7 @@ struct i2c_piix4_adapdata {
>  
>  	/* SB800 */
>  	bool sb800_main;
> -	u8 port;
> +	u8 port;		/* Port number, shifted */
>  };
>  
>  static int piix4_setup(struct pci_dev *PIIX4_dev,
> @@ -589,8 +589,8 @@ static s32 piix4_access_sb800(struct i2c
>  	smba_en_lo = inb_p(SB800_PIIX4_SMB_IDX + 1);
>  
>  	port = adapdata->port;
> -	if ((smba_en_lo & SB800_PIIX4_PORT_IDX_MASK) != (port << 1))
> -		outb_p((smba_en_lo & ~SB800_PIIX4_PORT_IDX_MASK) | (port << 1),
> +	if ((smba_en_lo & SB800_PIIX4_PORT_IDX_MASK) != port)
> +		outb_p((smba_en_lo & ~SB800_PIIX4_PORT_IDX_MASK) | port,
>  		       SB800_PIIX4_SMB_IDX + 1);
>  
>  	retval = piix4_access(adap, addr, flags, read_write,
> @@ -676,7 +676,7 @@ static int piix4_add_adapter(struct pci_
>  
>  	adapdata->smba = smba;
>  	adapdata->sb800_main = sb800_main;
> -	adapdata->port = port;
> +	adapdata->port = port << 1;
>  
>  	/* set up the sysfs linkage to our parent device */
>  	adap->dev.parent = &dev->dev;
> @@ -812,7 +812,7 @@ static void piix4_adap_remove(struct i2c
>  
>  	if (adapdata->smba) {
>  		i2c_del_adapter(adap);
> -		if (adapdata->port == 0) {
> +		if (adapdata->port == (0 << 1)) {

I suppose this is only for documentation purposes, right?

Reviewed-by: Mika Westerberg <mika.westerberg@linux.intel.com>

>  			release_region(adapdata->smba, SMBIOSIZE);
>  			if (adapdata->sb800_main)
>  				release_region(SB800_PIIX4_SMB_IDX, 2);
> 
> -- 
> Jean Delvare
> SUSE L3 Support