[PATCH v2] mt76: eeprom: tolerate corrected bit-flips

[PATCH v2] mt76: eeprom: tolerate corrected bit-flips

[Daniel Golle]

mtd_read() returns -EUCLEAN in case of corrected bit-flips.
As data was read, don't error out in this case.

Signed-off-by: Daniel Golle <daniel@makrotopia.org>
---
v2: fix wrong variable name

 drivers/net/wireless/mediatek/mt76/eeprom.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/net/wireless/mediatek/mt76/eeprom.c b/drivers/net/wireless/mediatek/mt76/eeprom.c
index 2d58aa31db934..4a5d14473ddc4 100644
--- a/drivers/net/wireless/mediatek/mt76/eeprom.c
+++ b/drivers/net/wireless/mediatek/mt76/eeprom.c
@@ -65,7 +65,7 @@ int mt76_get_of_eeprom(struct mt76_dev *dev, void *eep, int offset, int len)
 	offset = be32_to_cpup(list);
 	ret = mtd_read(mtd, offset, len, &retlen, eep);
 	put_mtd_device(mtd);
-	if (ret) {
+	if (ret && !mtd_is_bitflip(ret)) {
 		dev_err(dev->dev, "reading EEPROM from mtd %s failed: %i\n",
 			part, ret);
 		goto out_put_node;
-- 
2.34.0

Re: [PATCH v2] mt76: eeprom: tolerate corrected bit-flips

[Hauke Mehrtens]

On 11/25/21 8:45 PM, Daniel Golle wrote:
> mtd_read() returns -EUCLEAN in case of corrected bit-flips.
> As data was read, don't error out in this case.
> 
> Signed-off-by: Daniel Golle <daniel@makrotopia.org>

Acked-by: Hauke Mehrtens <hauke@hauke-m.de>

I tried a similar patch on my device before and it solved the problem too.

> ---
> v2: fix wrong variable name
> 
>   drivers/net/wireless/mediatek/mt76/eeprom.c | 2 +-
>   1 file changed, 1 insertion(+), 1 deletion(-)
> 
> diff --git a/drivers/net/wireless/mediatek/mt76/eeprom.c b/drivers/net/wireless/mediatek/mt76/eeprom.c
> index 2d58aa31db934..4a5d14473ddc4 100644
> --- a/drivers/net/wireless/mediatek/mt76/eeprom.c
> +++ b/drivers/net/wireless/mediatek/mt76/eeprom.c
> @@ -65,7 +65,7 @@ int mt76_get_of_eeprom(struct mt76_dev *dev, void *eep, int offset, int len)
>   	offset = be32_to_cpup(list);
>   	ret = mtd_read(mtd, offset, len, &retlen, eep);
>   	put_mtd_device(mtd);
> -	if (ret) {
> +	if (ret && !mtd_is_bitflip(ret)) {
>   		dev_err(dev->dev, "reading EEPROM from mtd %s failed: %i\n",
>   			part, ret);
>   		goto out_put_node;
> 

Re: [PATCH v2] mt76: eeprom: tolerate corrected bit-flips

[Felix Fietkau]

Hi,

On 2021-11-25 20:45, Daniel Golle wrote:
> mtd_read() returns -EUCLEAN in case of corrected bit-flips.
> As data was read, don't error out in this case.
> 
> Signed-off-by: Daniel Golle <daniel@makrotopia.org>
> ---
> v2: fix wrong variable name
> 
>   drivers/net/wireless/mediatek/mt76/eeprom.c | 2 +-
>   1 file changed, 1 insertion(+), 1 deletion(-)
> 
> diff --git a/drivers/net/wireless/mediatek/mt76/eeprom.c b/drivers/net/wireless/mediatek/mt76/eeprom.c
> index 2d58aa31db934..4a5d14473ddc4 100644
> --- a/drivers/net/wireless/mediatek/mt76/eeprom.c
> +++ b/drivers/net/wireless/mediatek/mt76/eeprom.c
> @@ -65,7 +65,7 @@ int mt76_get_of_eeprom(struct mt76_dev *dev, void *eep, int offset, int len)
>   	offset = be32_to_cpup(list);
>   	ret = mtd_read(mtd, offset, len, &retlen, eep);
>   	put_mtd_device(mtd);
> -	if (ret) {
> +	if (ret && !mtd_is_bitflip(ret)) {
unfortunately the patch is still incomplete. I will fold in the
following change to make it work:
---
--- a/drivers/net/wireless/mediatek/mt76/eeprom.c
+++ b/drivers/net/wireless/mediatek/mt76/eeprom.c
@@ -65,7 +65,9 @@ int mt76_get_of_eeprom(struct mt76_dev *dev, void *eep, int offset, int len)
  	offset = be32_to_cpup(list);
  	ret = mtd_read(mtd, offset, len, &retlen, eep);
  	put_mtd_device(mtd);
-	if (ret && !mtd_is_bitflip(ret)) {
+	if (mtd_is_bitflip(ret))
+		ret = 0;
+	if (ret) {
  		dev_err(dev->dev, "reading EEPROM from mtd %s failed: %i\n",
  			part, ret);
  		goto out_put_node;