[PATCH 1/3] wifi: mt76: mt7996: extend flexibility of mt7996_mcu_get_eeprom()

[Daniel Golle]

On Thu, Sep 26, 2024 at 11:24:38AM +0800, Shayne Chen wrote:
> Support passing customized buffer pointer and length to
> mt7996_mcu_get_eeprom().
> 
> This is the preparation for adding more variants support which needs to
> prefetch FEM module from efuse, and also fixes potential OOB issue when
> reading the last efuse block.
> 
> Co-developed-by: StanleyYP Wang <StanleyYP.Wang at mediatek.com>
> Signed-off-by: StanleyYP Wang <StanleyYP.Wang at mediatek.com>
> Signed-off-by: Shayne Chen <shayne.chen at mediatek.com>

Tested-by: Daniel Golle <daniel at makrotopia.org>

> ---
>  drivers/net/wireless/mediatek/mt76/mt7996/eeprom.c |  9 +++++++--
>  drivers/net/wireless/mediatek/mt76/mt7996/mcu.c    | 14 ++++++++++----
>  drivers/net/wireless/mediatek/mt76/mt7996/mt7996.h |  2 +-
>  3 files changed, 18 insertions(+), 7 deletions(-)
> 
> diff --git a/drivers/net/wireless/mediatek/mt76/mt7996/eeprom.c b/drivers/net/wireless/mediatek/mt76/mt7996/eeprom.c
> index 4a8237118287..861aba68a725 100644
> --- a/drivers/net/wireless/mediatek/mt76/mt7996/eeprom.c
> +++ b/drivers/net/wireless/mediatek/mt76/mt7996/eeprom.c
> @@ -86,8 +86,13 @@ static int mt7996_eeprom_load(struct mt7996_dev *dev)
>  		/* read eeprom data from efuse */
>  		block_num = DIV_ROUND_UP(MT7996_EEPROM_SIZE, eeprom_blk_size);
>  		for (i = 0; i < block_num; i++) {
> -			ret = mt7996_mcu_get_eeprom(dev, i * eeprom_blk_size);
> -			if (ret < 0)
> +			u32 len = eeprom_blk_size;
> +
> +			if (i == block_num - 1)
> +				len = MT7996_EEPROM_SIZE % eeprom_blk_size;
> +			ret = mt7996_mcu_get_eeprom(dev, i * eeprom_blk_size,
> +						    NULL, len);
> +			if (ret && ret != -EINVAL)
>  				return ret;
>  		}
>  	}
> diff --git a/drivers/net/wireless/mediatek/mt76/mt7996/mcu.c b/drivers/net/wireless/mediatek/mt76/mt7996/mcu.c
> index 327337b31279..fa7832f625d7 100644
> --- a/drivers/net/wireless/mediatek/mt76/mt7996/mcu.c
> +++ b/drivers/net/wireless/mediatek/mt76/mt7996/mcu.c
> @@ -3548,7 +3548,7 @@ int mt7996_mcu_set_eeprom(struct mt7996_dev *dev)
>  				 &req, sizeof(req), true);
>  }
>  
> -int mt7996_mcu_get_eeprom(struct mt7996_dev *dev, u32 offset)
> +int mt7996_mcu_get_eeprom(struct mt7996_dev *dev, u32 offset, u8 *buf, u32 buf_len)
>  {
>  	struct {
>  		u8 _rsv[4];
> @@ -3577,15 +3577,21 @@ int mt7996_mcu_get_eeprom(struct mt7996_dev *dev, u32 offset)
>  	valid = le32_to_cpu(*(__le32 *)(skb->data + 16));
>  	if (valid) {
>  		u32 addr = le32_to_cpu(*(__le32 *)(skb->data + 12));
> -		u8 *buf = (u8 *)dev->mt76.eeprom.data + addr;
> +
> +		if (!buf)
> +			buf = (u8 *)dev->mt76.eeprom.data + addr;
> +		if (!buf_len || buf_len > MT7996_EEPROM_BLOCK_SIZE)
> +			buf_len = MT7996_EEPROM_BLOCK_SIZE;
>  
>  		skb_pull(skb, 48);
> -		memcpy(buf, skb->data, MT7996_EEPROM_BLOCK_SIZE);
> +		memcpy(buf, skb->data, buf_len);
> +	} else {
> +		ret = -EINVAL;
>  	}
>  
>  	dev_kfree_skb(skb);
>  
> -	return 0;
> +	return ret;
>  }
>  
>  int mt7996_mcu_get_eeprom_free_block(struct mt7996_dev *dev, u8 *block_num)
> diff --git a/drivers/net/wireless/mediatek/mt76/mt7996/mt7996.h b/drivers/net/wireless/mediatek/mt76/mt7996/mt7996.h
> index ab8c9070630b..55aa5f6ab77d 100644
> --- a/drivers/net/wireless/mediatek/mt76/mt7996/mt7996.h
> +++ b/drivers/net/wireless/mediatek/mt76/mt7996/mt7996.h
> @@ -476,7 +476,7 @@ int mt7996_mcu_set_fixed_rate_ctrl(struct mt7996_dev *dev,
>  int mt7996_mcu_set_fixed_field(struct mt7996_dev *dev, struct ieee80211_vif *vif,
>  			       struct ieee80211_sta *sta, void *data, u32 field);
>  int mt7996_mcu_set_eeprom(struct mt7996_dev *dev);
> -int mt7996_mcu_get_eeprom(struct mt7996_dev *dev, u32 offset);
> +int mt7996_mcu_get_eeprom(struct mt7996_dev *dev, u32 offset, u8 *buf, u32 buf_len);
>  int mt7996_mcu_get_eeprom_free_block(struct mt7996_dev *dev, u8 *block_num);
>  int mt7996_mcu_get_chip_config(struct mt7996_dev *dev, u32 *cap);
>  int mt7996_mcu_set_ser(struct mt7996_dev *dev, u8 action, u8 set, u8 band);
> -- 
> 2.39.2
>