Re: [PATCH] i2c-pxa: fastmode support (with suggested fixes)

[Ben Dooks <ben-linux-elnMNo+KYs3YtjvyW6yDsg@public.gmane.org>]

On Fri, Aug 01, 2008 at 11:08:15AM +0100, Jonathan Cameron wrote:
> From: Jonathan Cameron <jic23-KWPb1pKIrIJaa/9Udqfwiw@public.gmane.org>
> 
> Add fast_mode option to i2c_pxa_platform_data and use it to set the ICR_FM
> bit appropriately when i2c_pxa_reset is called. Parameter called fast_mode
> rather than frequency as this driver is also used for the i2c_pxa_pwr bus
> which has different normal and fast frequencies.

this looks fine, the only problem is that we're still going
through some reorganisation of the ARM headers... given this
is really a new feature, I'm not going to apply it until closer
to the next release.

I may even have a look to see what the state of splitting pxa-regs
up further into something that might be more maintainable...
 
> Signed-off-by: Jonathan Cameron <jic23-KWPb1pKIrIJaa/9Udqfwiw@public.gmane.org>
> 
> --
> This is basically a repost of the original patch with use_pio and
> fast_mode converted to bit fields as suggested / agreed by Eric Miao and
> Ben Dooks.
> 
>  drivers/i2c/busses/i2c-pxa.c        |    6 ++++--
>  include/asm-arm/arch-pxa/i2c.h      |    3 ++-
>  include/asm-arm/arch-pxa/pxa-regs.h |    1 +
>  3 files changed, 7 insertions(+), 3 deletions(-)
> 
> --- a/drivers/i2c/busses/i2c-pxa.c	2008-07-31 12:02:42.000000000 +0100
> +++ b/drivers/i2c/busses/i2c-pxa.c	2008-08-01 10:50:38.000000000 +0100
> @@ -65,7 +65,8 @@ struct pxa_i2c {
>  	unsigned long		iosize;
>  
>  	int			irq;
> -	int			use_pio;
> +	unsigned int		use_pio:1;
> +	unsigned int		fast_mode:1;
>  };
>  
>  #define _IBMR(i2c)	((i2c)->reg_base + 0)
> @@ -364,7 +365,7 @@ static void i2c_pxa_reset(struct pxa_i2c
>  	writel(i2c->slave_addr, _ISAR(i2c));
>  
>  	/* set control register values */
> -	writel(I2C_ICR_INIT, _ICR(i2c));
> +	writel(I2C_ICR_INIT | (i2c->fast_mode ? ICR_FM : 0), _ICR(i2c));
>  
>  #ifdef CONFIG_I2C_PXA_SLAVE
>  	dev_info(&i2c->adap.dev, "Enabling slave mode\n");
> @@ -1013,6 +1014,7 @@ static int i2c_pxa_probe(struct platform
>  	if (plat) {
>  		i2c->adap.class = plat->class;
>  		i2c->use_pio = plat->use_pio;
> +		i2c->fast_mode = plat->fast_mode;
>  	}
>  
>  	if (i2c->use_pio) {
> --- a/include/asm-arm/arch-pxa/i2c.h	2008-07-31 12:00:05.000000000 +0100
> +++ b/include/asm-arm/arch-pxa/i2c.h	2008-08-01 10:51:40.000000000 +0100
> @@ -65,7 +65,8 @@ struct i2c_pxa_platform_data {
>  	unsigned int		slave_addr;
>  	struct i2c_slave_client	*slave;
>  	unsigned int		class;
> -	int			use_pio;
> +	unsigned int		use_pio:1;
> +	unsigned int		fast_mode:1;
>  };
>  
>  extern void pxa_set_i2c_info(struct i2c_pxa_platform_data *info);
> --- a/include/asm-arm/arch-pxa/pxa-regs.h	2008-07-31 12:02:51.000000000 +0100
> +++ b/include/asm-arm/arch-pxa/pxa-regs.h	2008-07-31 12:34:44.000000000 +0100
> @@ -448,6 +448,7 @@
>  #define ICR_ALDIE	(1 << 12)	   /* enable arbitration interrupt */
>  #define ICR_SADIE	(1 << 13)	   /* slave address detected int enable */
>  #define ICR_UR		(1 << 14)	   /* unit reset */
> +#define ICR_FM		(1 << 15)	   /* fast mode */
>  
>  #define ISR_RWM		(1 << 0)	   /* read/write mode */
>  #define ISR_ACKNAK	(1 << 1)	   /* ack/nak status */
> 
> _______________________________________________
> i2c mailing list
> i2c-GZX6beZjE8VD60Wz+7aTrA@public.gmane.org
> http://lists.lm-sensors.org/mailman/listinfo/i2c

-- 
Ben (ben-elnMNo+KYs3YtjvyW6yDsg@public.gmane.org, http://www.fluff.org/)

  'a smiley only costs 4 bytes'

_______________________________________________
i2c mailing list
i2c-GZX6beZjE8VD60Wz+7aTrA@public.gmane.org
http://lists.lm-sensors.org/mailman/listinfo/i2c