Re: [PATCHv3 8/8] i2c: omap: cleanup the sysc write

[Felipe Balbi <balbi-l0cyMroinI0@public.gmane.org>]

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Hi,

On Mon, Nov 05, 2012 at 05:53:43PM +0530, Shubhrajyoti D wrote:
> Currently after the reset the sysc is written with hardcoded values.
> The patch reads the sysc register and writes back the same value
> after reset.
> 
> - Some unnecessary rev checks can be optimised.
> - Also due to whatever reason the hwmod flags are changed
> we will not reset the values.
> - In some of the cases the minor values of the 2430 register
> is different(0x37) in that case the autoidle setting may be missed.
> 
> Signed-off-by: Shubhrajyoti D <shubhrajyoti-l0cyMroinI0@public.gmane.org>
> ---
>  drivers/i2c/busses/i2c-omap.c |   20 +++++---------------
>  1 files changed, 5 insertions(+), 15 deletions(-)
> 
> diff --git a/drivers/i2c/busses/i2c-omap.c b/drivers/i2c/busses/i2c-omap.c
> index 25f1564..a09acdc 100644
> --- a/drivers/i2c/busses/i2c-omap.c
> +++ b/drivers/i2c/busses/i2c-omap.c
> @@ -302,7 +302,11 @@ static void __omap_i2c_init(struct omap_i2c_dev *dev)
>  static int omap_i2c_reset(struct omap_i2c_dev *dev)
>  {
>  	unsigned long timeout;
> +	u16 sysc;
> +
>  	if (dev->rev >= OMAP_I2C_OMAP1_REV_2) {
> +		sysc = omap_i2c_read_reg(dev, OMAP_I2C_SYSC_REG);
> +
>  		/* Disable I2C controller before soft reset */
>  		omap_i2c_write_reg(dev, OMAP_I2C_CON_REG,
>  			omap_i2c_read_reg(dev, OMAP_I2C_CON_REG) &
> @@ -324,22 +328,8 @@ static int omap_i2c_reset(struct omap_i2c_dev *dev)
>  		}
>  
>  		/* SYSC register is cleared by the reset; rewrite it */
> -		if (dev->rev == OMAP_I2C_REV_ON_2430) {
> -
> -			omap_i2c_write_reg(dev, OMAP_I2C_SYSC_REG,
> -					   SYSC_AUTOIDLE_MASK);
> +		omap_i2c_write_reg(dev, OMAP_I2C_SYSC_REG, sysc);
>  
> -		} else if (dev->rev >= OMAP_I2C_REV_ON_3430_3530) {
> -			dev->syscstate = SYSC_AUTOIDLE_MASK;
> -			dev->syscstate |= SYSC_ENAWAKEUP_MASK;
> -			dev->syscstate |= (SYSC_IDLEMODE_SMART <<
> -			      __ffs(SYSC_SIDLEMODE_MASK));
> -			dev->syscstate |= (SYSC_CLOCKACTIVITY_FCLK <<
> -			      __ffs(SYSC_CLOCKACTIVITY_MASK));
> -
> -			omap_i2c_write_reg(dev, OMAP_I2C_SYSC_REG,
> -							dev->syscstate);
> -		}

not sure if this will work. What about the first time you call reset() ?
won't SYSC just contain the reset values ?

-- 
balbi

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