Subject: Re: [PATCH v2 net-next 5/5] net: ethernet: mtk_wed: add reset/reset_complete callbacks

From: Leon Romanovsky <[email-masked]>
Date: Wed, 4 Jan 2023 16:17:21 +0200

On Wed, Jan 04, 2023 at 03:03:14PM +0100, Lorenzo Bianconi wrote:
> Introduce reset and reset_complete wlan callback to schedule WLAN driver
> reset when ethernet/wed driver is resetting.
> 
> Tested-by: Daniel Golle <[email-masked]>
> Co-developed-by: Sujuan Chen <[email-masked]>
> Signed-off-by: Sujuan Chen <[email-masked]>
> Signed-off-by: Lorenzo Bianconi <[email-masked]>
> ---
>  drivers/net/ethernet/mediatek/mtk_eth_soc.c |  6 ++++
>  drivers/net/ethernet/mediatek/mtk_wed.c     | 40 +++++++++++++++++++++
>  drivers/net/ethernet/mediatek/mtk_wed.h     |  8 +++++
>  include/linux/soc/mediatek/mtk_wed.h        |  2 ++
>  4 files changed, 56 insertions(+)
> 
> diff --git a/drivers/net/ethernet/mediatek/mtk_eth_soc.c b/drivers/net/ethernet/mediatek/mtk_eth_soc.c
> index bafae4f0312e..2d74e26f45c9 100644
> --- a/drivers/net/ethernet/mediatek/mtk_eth_soc.c
> +++ b/drivers/net/ethernet/mediatek/mtk_eth_soc.c
> @@ -3913,6 +3913,10 @@ static void mtk_pending_work(struct work_struct *work)
>  		mtk_w32(eth, val, MTK_MAC_MCR(i));
>  	}
>  
> +	rtnl_unlock();
> +	mtk_wed_fe_reset();
> +	rtnl_lock();

Is it safe to call rtnl_unlock(), perform some work and lock again?

> +
>  	/* stop all devices to make sure that dma is properly shut down */
>  	for (i = 0; i < MTK_MAC_COUNT; i++) {
>  		if (!eth->netdev[i] || !netif_running(eth->netdev[i]))
> @@ -3949,6 +3953,8 @@ static void mtk_pending_work(struct work_struct *work)
>  
>  	clear_bit(MTK_RESETTING, &eth->state);
>  
> +	mtk_wed_fe_reset_complete();
> +
>  	rtnl_unlock();
>  }
>  
> diff --git a/drivers/net/ethernet/mediatek/mtk_wed.c b/drivers/net/ethernet/mediatek/mtk_wed.c
> index a6271449617f..4854993f2941 100644
> --- a/drivers/net/ethernet/mediatek/mtk_wed.c
> +++ b/drivers/net/ethernet/mediatek/mtk_wed.c
> @@ -206,6 +206,46 @@ mtk_wed_wo_reset(struct mtk_wed_device *dev)
>  	iounmap(reg);
>  }
>  
> +void mtk_wed_fe_reset(void)
> +{
> +	int i;
> +
> +	mutex_lock(&hw_lock);
> +
> +	for (i = 0; i < ARRAY_SIZE(hw_list); i++) {
> +		struct mtk_wed_hw *hw = hw_list[i];
> +		struct mtk_wed_device *dev = hw->wed_dev;
> +
> +		if (!dev || !dev->wlan.reset)
> +			continue;
> +
> +		/* reset callback blocks until WLAN reset is completed */
> +		if (dev->wlan.reset(dev))
> +			dev_err(dev->dev, "wlan reset failed\n");
> +	}
> +
> +	mutex_unlock(&hw_lock);
> +}
> +
> +void mtk_wed_fe_reset_complete(void)
> +{
> +	int i;
> +
> +	mutex_lock(&hw_lock);
> +
> +	for (i = 0; i < ARRAY_SIZE(hw_list); i++) {
> +		struct mtk_wed_hw *hw = hw_list[i];
> +		struct mtk_wed_device *dev = hw->wed_dev;
> +
> +		if (!dev || !dev->wlan.reset_complete)
> +			continue;
> +
> +		dev->wlan.reset_complete(dev);
> +	}
> +
> +	mutex_unlock(&hw_lock);
> +}
> +
>  static struct mtk_wed_hw *
>  mtk_wed_assign(struct mtk_wed_device *dev)
>  {
> diff --git a/drivers/net/ethernet/mediatek/mtk_wed.h b/drivers/net/ethernet/mediatek/mtk_wed.h
> index e012b8a82133..6108a7e69a80 100644
> --- a/drivers/net/ethernet/mediatek/mtk_wed.h
> +++ b/drivers/net/ethernet/mediatek/mtk_wed.h
> @@ -128,6 +128,8 @@ void mtk_wed_add_hw(struct device_node *np, struct mtk_eth *eth,
>  void mtk_wed_exit(void);
>  int mtk_wed_flow_add(int index);
>  void mtk_wed_flow_remove(int index);
> +void mtk_wed_fe_reset(void);
> +void mtk_wed_fe_reset_complete(void);
>  #else
>  static inline void
>  mtk_wed_add_hw(struct device_node *np, struct mtk_eth *eth,
> @@ -146,6 +148,12 @@ static inline int mtk_wed_flow_add(int index)
>  static inline void mtk_wed_flow_remove(int index)
>  {
>  }
> +static inline void mtk_wed_fe_reset(void)
> +{
> +}
> +static inline void mtk_wed_fe_reset_complete(void)
> +{
> +}
>  
>  #endif
>  
> diff --git a/include/linux/soc/mediatek/mtk_wed.h b/include/linux/soc/mediatek/mtk_wed.h
> index db637a13888d..ddff54fc9717 100644
> --- a/include/linux/soc/mediatek/mtk_wed.h
> +++ b/include/linux/soc/mediatek/mtk_wed.h
> @@ -150,6 +150,8 @@ struct mtk_wed_device {
>  		void (*release_rx_buf)(struct mtk_wed_device *wed);
>  		void (*update_wo_rx_stats)(struct mtk_wed_device *wed,
>  					   struct mtk_wed_wo_rx_stats *stats);
> +		int (*reset)(struct mtk_wed_device *wed);
> +		int (*reset_complete)(struct mtk_wed_device *wed);

I don't see any driver implementation of these callbacks in this series.
Did I miss it?

Thanks

>  	} wlan;
>  #endif
>  };
> -- 
> 2.39.0