Subject: Re: [net-next PATCH v3 1/6] net: cpsw: enhance pinctrl support

From: Tony Lindgren <[email-masked]>
Date: Mon, 27 May 2013 14:36:01 -0700

* Mugunthan V N <[email-masked]> [130526 11:28]:
> From: Hebbar Gururaja <[email-masked]>
> 
> Amend cpsw controller to optionally take a pin control handle and set
> the state of the pins to:
> 
> - "default" on boot, resume
> - "sleep" on suspend()
> 
> This should make it possible to optimize energy usage for the pins
> for the suspend/resume cycle.
> 
> If any of the above pin states are missing in dt, a warning message
> about the missing state is displayed.
> If certain pin-states are not available, to remove this warning message
> pass respective state name with null phandler.
> 
> Signed-off-by: Hebbar Gururaja <[email-masked]>
> Signed-off-by: Mugunthan V N <[email-masked]>
> ---
>  drivers/net/ethernet/ti/cpsw.c |   48 ++++++++++++++++++++++++++++++++++++++++
>  1 file changed, 48 insertions(+)
> 
> diff --git a/drivers/net/ethernet/ti/cpsw.c b/drivers/net/ethernet/ti/cpsw.c
> index 21a5b29..c9ed730 100644
> --- a/drivers/net/ethernet/ti/cpsw.c
> +++ b/drivers/net/ethernet/ti/cpsw.c
> @@ -35,6 +35,7 @@
>  #include <linux/if_vlan.h>
>  
>  #include <linux/platform_data/cpsw.h>
> +#include <linux/pinctrl/consumer.h>
>  
>  #include "cpsw_ale.h"
>  #include "cpts.h"
> @@ -351,6 +352,11 @@ struct cpsw_priv {
>  	bool irq_enabled;
>  	struct cpts *cpts;
>  	u32 emac_port;
> +
> +	/* Two optional pin states - default & sleep */
> +	struct pinctrl		*pinctrl;
> +	struct pinctrl_state	*pins_def;
> +	struct pinctrl_state	*pins_sleep;
>  };

Which pins do you need to dynamically remux? If it's not all
the pins, you should have three sets: default, active and idle.
This way the static pins in the default group don't need to be
constantly toggled.

Regards,

Tony