Re: [PATCH] initialize struct otg_fsm earlier

[Peter Chen <peter.chen@kernel.org>]

On 23-11-13 18:31:20, Oliver Neukum wrote:
> The earlier fix bf88fef0b6f1 ("usb: otg-fsm: Fix hrtimer list
> corruption") in effect hid an issue with intialization.

Typo, hit an issue with initialization.

> In effect it replaces the racy continous reinitialization
> of fsm->hnp_polling_work with a delayed one-time
> initialization.
> 
> This just makes no sense. As a single initialization
> is sufficient, the clean solution is just to do it once
> and do it early enough.

The phy-fsl-usb is not the only user, there are other users, eg,
chipidea.

Peter
> 
> Fixes: bf88fef0b6f1 ("usb: otg-fsm: Fix hrtimer list corruption")
> Signed-off-by: Oliver Neukum <oneukum@suse.com>
> ---
>  drivers/usb/common/usb-otg-fsm.c | 7 +------
>  drivers/usb/phy/phy-fsl-usb.c    | 1 +
>  include/linux/usb/otg-fsm.h      | 1 -
>  3 files changed, 2 insertions(+), 7 deletions(-)
> 
> diff --git a/drivers/usb/common/usb-otg-fsm.c b/drivers/usb/common/usb-otg-fsm.c
> index 0697fde51d00..0aa2eb7396ce 100644
> --- a/drivers/usb/common/usb-otg-fsm.c
> +++ b/drivers/usb/common/usb-otg-fsm.c
> @@ -117,7 +117,7 @@ static void otg_leave_state(struct otg_fsm *fsm, enum usb_otg_state old_state)
>  	}
>  }
>  
> -static void otg_hnp_polling_work(struct work_struct *work)
> +void otg_hnp_polling_work(struct work_struct *work)
>  {
>  	struct otg_fsm *fsm = container_of(to_delayed_work(work),
>  				struct otg_fsm, hnp_polling_work);
> @@ -193,11 +193,6 @@ static void otg_start_hnp_polling(struct otg_fsm *fsm)
>  	if (!fsm->host_req_flag)
>  		return;
>  
> -	if (!fsm->hnp_work_inited) {
> -		INIT_DELAYED_WORK(&fsm->hnp_polling_work, otg_hnp_polling_work);
> -		fsm->hnp_work_inited = true;
> -	}
> -
>  	schedule_delayed_work(&fsm->hnp_polling_work,
>  					msecs_to_jiffies(T_HOST_REQ_POLL));
>  }
> diff --git a/drivers/usb/phy/phy-fsl-usb.c b/drivers/usb/phy/phy-fsl-usb.c
> index 79617bb0a70e..4553aaab3761 100644
> --- a/drivers/usb/phy/phy-fsl-usb.c
> +++ b/drivers/usb/phy/phy-fsl-usb.c
> @@ -844,6 +844,7 @@ int usb_otg_start(struct platform_device *pdev)
>  
>  	/* Initialize the state machine structure with default values */
>  	SET_OTG_STATE(otg_trans, OTG_STATE_UNDEFINED);
> +	INIT_DELAYED_WORK(&fsm->hnp_polling_work, otg_hnp_polling_work);
>  	fsm->otg = p_otg->phy.otg;
>  
>  	/* We don't require predefined MEM/IRQ resource index */
> diff --git a/include/linux/usb/otg-fsm.h b/include/linux/usb/otg-fsm.h
> index 6135d076c53d..cc0bc4edf227 100644
> --- a/include/linux/usb/otg-fsm.h
> +++ b/include/linux/usb/otg-fsm.h
> @@ -183,7 +183,6 @@ struct otg_fsm {
>  	struct mutex lock;
>  	u8 *host_req_flag;
>  	struct delayed_work hnp_polling_work;
> -	bool hnp_work_inited;
>  	bool state_changed;
>  };
>  
> -- 
> 2.42.0
> 

-- 

Thanks,
Peter Chen