[4/5] mtd: spi-nor: Move clear_sr_bp() to 'struct spi_nor_flash_parameter'
diff mbox series

Message ID 20190823155325.13459-5-tudor.ambarus@microchip.com
State Changes Requested
Delegated to: Ambarus Tudor
Headers show
Series
  • mtd: spi-nor: move manuf out of the core - batch 0
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Commit Message

Ambarus Tudor Aug. 23, 2019, 3:53 p.m. UTC
From: Tudor Ambarus <tudor.ambarus@microchip.com>

All flash parameters and settings should reside inside
'struct spi_nor_flash_parameter'. Move clear_sr_bp() from
'struct spi_nor' to 'struct spi_nor_flash_parameter'.

Rename clear_sr_bp()/disable_block_protection() to better indicate
what the function does.

Signed-off-by: Tudor Ambarus <tudor.ambarus@microchip.com>
---
 drivers/mtd/spi-nor/spi-nor.c | 47 +++++++++++++++++++++++++++++++++----------
 include/linux/mtd/spi-nor.h   |  5 ++---
 2 files changed, 38 insertions(+), 14 deletions(-)

Comments

Ambarus Tudor Aug. 24, 2019, 3:53 a.m. UTC | #1
On 08/23/2019 06:53 PM, Tudor Ambarus - M18064 wrote:
> +	 * configuration register Quad Enable bit is one, only the the
								^duplication
Boris Brezillon Aug. 25, 2019, 11:33 a.m. UTC | #2
On Fri, 23 Aug 2019 15:53:41 +0000
<Tudor.Ambarus@microchip.com> wrote:

> From: Tudor Ambarus <tudor.ambarus@microchip.com>
> 
> All flash parameters and settings should reside inside
> 'struct spi_nor_flash_parameter'. Move clear_sr_bp() from
> 'struct spi_nor' to 'struct spi_nor_flash_parameter'.
> 
> Rename clear_sr_bp()/disable_block_protection() to better indicate
> what the function does.
> 
> Signed-off-by: Tudor Ambarus <tudor.ambarus@microchip.com>

Reviewed-by: Boris Brezillon <boris.brezillon@collabora.com>

> ---
>  drivers/mtd/spi-nor/spi-nor.c | 47 +++++++++++++++++++++++++++++++++----------
>  include/linux/mtd/spi-nor.h   |  5 ++---
>  2 files changed, 38 insertions(+), 14 deletions(-)
> 
> diff --git a/drivers/mtd/spi-nor/spi-nor.c b/drivers/mtd/spi-nor/spi-nor.c
> index 6bd104c29cd9..15b0b1148bf3 100644
> --- a/drivers/mtd/spi-nor/spi-nor.c
> +++ b/drivers/mtd/spi-nor/spi-nor.c
> @@ -4477,20 +4477,45 @@ static int spi_nor_quad_enable(struct spi_nor *nor)
>  	return nor->params.quad_enable(nor);
>  }
>  
> +/**
> + * spi_nor_disable_block_protection() - Disable the write block protection
> + * during power-up.
> + * @nor:                pointer to a 'struct spi_nor'
> + *
> + * Some spi-nor flashes are write protected by default after a power-on reset
> + * cycle, in order to avoid inadvertend writes during power-up. Backward
> + * compatibility imposes to disable the write block protection at power-up
> + * by default.
> + *
> + * Return: 0 on success, -errno otherwise.
> + */
> +static int spi_nor_disable_block_protection(struct spi_nor *nor)
> +{
> +	if (!nor->params.disable_block_protection)
> +		return 0;
> +
> +	/*
> +	 * In case of the legacy quad enable requirements are set, if the
> +	 * configuration register Quad Enable bit is one, only the the
> +	 * Write Status (01h) command with two data bytes may be used to clear
> +	 * the block protection bits.
> +	 */
> +	if (nor->params.quad_enable == spansion_quad_enable)
> +		nor->params.disable_block_protection =
> +			spi_nor_spansion_clear_sr_bp;
> +
> +	return nor->params.disable_block_protection(nor);
> +}
> +
>  static int spi_nor_init(struct spi_nor *nor)
>  {
>  	int err;
>  
> -	if (nor->clear_sr_bp) {
> -		if (nor->quad_enable == spansion_quad_enable)
> -			nor->clear_sr_bp = spi_nor_spansion_clear_sr_bp;
> -
> -		err = nor->clear_sr_bp(nor);
> -		if (err) {
> -			dev_err(nor->dev,
> -				"fail to clear block protection bits\n");
> -			return err;
> -		}
> +	err = spi_nor_disable_block_protection(nor);
> +	if (err) {
> +		dev_err(nor->dev,
> +			"fail to unlock the flash at init (err = %d)\n", err);
> +		return err;
>  	}
>  
>  	err = spi_nor_quad_enable(nor);
> @@ -4635,7 +4660,7 @@ int spi_nor_scan(struct spi_nor *nor, const char *name,
>  	    JEDEC_MFR(nor->info) == SNOR_MFR_INTEL ||
>  	    JEDEC_MFR(nor->info) == SNOR_MFR_SST ||
>  	    nor->info->flags & SPI_NOR_HAS_LOCK)
> -		nor->clear_sr_bp = spi_nor_clear_sr_bp;
> +		nor->params.disable_block_protection = spi_nor_clear_sr_bp;
>  
>  	/* Parse the Serial Flash Discoverable Parameters table. */
>  	ret = spi_nor_init_params(nor);
> diff --git a/include/linux/mtd/spi-nor.h b/include/linux/mtd/spi-nor.h
> index 17787238f0e9..399ac34a529d 100644
> --- a/include/linux/mtd/spi-nor.h
> +++ b/include/linux/mtd/spi-nor.h
> @@ -480,6 +480,7 @@ struct spi_nor;
>   * @page_programs:	page program capabilities ordered by priority: the
>   *                      higher index in the array, the higher priority.
>   * @quad_enable:	enables SPI NOR quad mode.
> + * @disable_block_protection: disables block protection during power-up.
>   */
>  struct spi_nor_flash_parameter {
>  	u64				size;
> @@ -490,6 +491,7 @@ struct spi_nor_flash_parameter {
>  	struct spi_nor_pp_command	page_programs[SNOR_CMD_PP_MAX];
>  
>  	int (*quad_enable)(struct spi_nor *nor);
> +	int (*disable_block_protection)(struct spi_nor *nor);
>  };
>  
>  /**
> @@ -535,8 +537,6 @@ struct flash_info;
>   * @flash_unlock:	[FLASH-SPECIFIC] unlock a region of the SPI NOR
>   * @flash_is_locked:	[FLASH-SPECIFIC] check if a region of the SPI NOR is
>   *			completely locked
> - * @clear_sr_bp:	[FLASH-SPECIFIC] clears the Block Protection Bits from
> - *			the SPI NOR Status Register.
>   * @params:		[FLASH-SPECIFIC] SPI-NOR flash parameters and settings.
>   *                      The structure includes legacy flash parameters and
>   *                      settings that can be overwritten by the spi_nor_fixups
> @@ -578,7 +578,6 @@ struct spi_nor {
>  	int (*flash_lock)(struct spi_nor *nor, loff_t ofs, uint64_t len);
>  	int (*flash_unlock)(struct spi_nor *nor, loff_t ofs, uint64_t len);
>  	int (*flash_is_locked)(struct spi_nor *nor, loff_t ofs, uint64_t len);
> -	int (*clear_sr_bp)(struct spi_nor *nor);
>  	struct spi_nor_flash_parameter params;
>  
>  	void *priv;
Boris Brezillon Aug. 25, 2019, 1:09 p.m. UTC | #3
On Fri, 23 Aug 2019 15:53:41 +0000
<Tudor.Ambarus@microchip.com> wrote:

> From: Tudor Ambarus <tudor.ambarus@microchip.com>
> 
> All flash parameters and settings should reside inside
> 'struct spi_nor_flash_parameter'. Move clear_sr_bp() from
> 'struct spi_nor' to 'struct spi_nor_flash_parameter'.
> 
> Rename clear_sr_bp()/disable_block_protection() to better indicate
> what the function does.
> 
> Signed-off-by: Tudor Ambarus <tudor.ambarus@microchip.com>
> ---
>  drivers/mtd/spi-nor/spi-nor.c | 47 +++++++++++++++++++++++++++++++++----------
>  include/linux/mtd/spi-nor.h   |  5 ++---
>  2 files changed, 38 insertions(+), 14 deletions(-)
> 
> diff --git a/drivers/mtd/spi-nor/spi-nor.c b/drivers/mtd/spi-nor/spi-nor.c
> index 6bd104c29cd9..15b0b1148bf3 100644
> --- a/drivers/mtd/spi-nor/spi-nor.c
> +++ b/drivers/mtd/spi-nor/spi-nor.c
> @@ -4477,20 +4477,45 @@ static int spi_nor_quad_enable(struct spi_nor *nor)
>  	return nor->params.quad_enable(nor);
>  }
>  
> +/**
> + * spi_nor_disable_block_protection() - Disable the write block protection
> + * during power-up.
> + * @nor:                pointer to a 'struct spi_nor'
> + *
> + * Some spi-nor flashes are write protected by default after a power-on reset
> + * cycle, in order to avoid inadvertend writes during power-up. Backward
> + * compatibility imposes to disable the write block protection at power-up
> + * by default.
> + *
> + * Return: 0 on success, -errno otherwise.
> + */
> +static int spi_nor_disable_block_protection(struct spi_nor *nor)
> +{
> +	if (!nor->params.disable_block_protection)
> +		return 0;
> +
> +	/*
> +	 * In case of the legacy quad enable requirements are set, if the
> +	 * configuration register Quad Enable bit is one, only the the
> +	 * Write Status (01h) command with two data bytes may be used to clear
> +	 * the block protection bits.
> +	 */
> +	if (nor->params.quad_enable == spansion_quad_enable)
> +		nor->params.disable_block_protection =
> +			spi_nor_spansion_clear_sr_bp;

Hm, doesn't look right to adjust the function pointer just before
calling it. Can't we move that logic earlier (when doing the
default/manufacturer specific init)? Also, as I said in one of my
previous emails, I'd prefer to have this hook moved to
spi_nor_locking_ops and just have a flag to reflect when block
protection can be disabled.

> +
> +	return nor->params.disable_block_protection(nor);
> +}
> +
>  static int spi_nor_init(struct spi_nor *nor)
>  {
>  	int err;
>  
> -	if (nor->clear_sr_bp) {
> -		if (nor->quad_enable == spansion_quad_enable)
> -			nor->clear_sr_bp = spi_nor_spansion_clear_sr_bp;
> -
> -		err = nor->clear_sr_bp(nor);
> -		if (err) {
> -			dev_err(nor->dev,
> -				"fail to clear block protection bits\n");
> -			return err;
> -		}
> +	err = spi_nor_disable_block_protection(nor);
> +	if (err) {
> +		dev_err(nor->dev,
> +			"fail to unlock the flash at init (err = %d)\n", err);
> +		return err;
>  	}
>  
>  	err = spi_nor_quad_enable(nor);
> @@ -4635,7 +4660,7 @@ int spi_nor_scan(struct spi_nor *nor, const char *name,
>  	    JEDEC_MFR(nor->info) == SNOR_MFR_INTEL ||
>  	    JEDEC_MFR(nor->info) == SNOR_MFR_SST ||
>  	    nor->info->flags & SPI_NOR_HAS_LOCK)
> -		nor->clear_sr_bp = spi_nor_clear_sr_bp;
> +		nor->params.disable_block_protection = spi_nor_clear_sr_bp;
>  
>  	/* Parse the Serial Flash Discoverable Parameters table. */
>  	ret = spi_nor_init_params(nor);
> diff --git a/include/linux/mtd/spi-nor.h b/include/linux/mtd/spi-nor.h
> index 17787238f0e9..399ac34a529d 100644
> --- a/include/linux/mtd/spi-nor.h
> +++ b/include/linux/mtd/spi-nor.h
> @@ -480,6 +480,7 @@ struct spi_nor;
>   * @page_programs:	page program capabilities ordered by priority: the
>   *                      higher index in the array, the higher priority.
>   * @quad_enable:	enables SPI NOR quad mode.
> + * @disable_block_protection: disables block protection during power-up.
>   */
>  struct spi_nor_flash_parameter {
>  	u64				size;
> @@ -490,6 +491,7 @@ struct spi_nor_flash_parameter {
>  	struct spi_nor_pp_command	page_programs[SNOR_CMD_PP_MAX];
>  
>  	int (*quad_enable)(struct spi_nor *nor);
> +	int (*disable_block_protection)(struct spi_nor *nor);
>  };
>  
>  /**
> @@ -535,8 +537,6 @@ struct flash_info;
>   * @flash_unlock:	[FLASH-SPECIFIC] unlock a region of the SPI NOR
>   * @flash_is_locked:	[FLASH-SPECIFIC] check if a region of the SPI NOR is
>   *			completely locked
> - * @clear_sr_bp:	[FLASH-SPECIFIC] clears the Block Protection Bits from
> - *			the SPI NOR Status Register.
>   * @params:		[FLASH-SPECIFIC] SPI-NOR flash parameters and settings.
>   *                      The structure includes legacy flash parameters and
>   *                      settings that can be overwritten by the spi_nor_fixups
> @@ -578,7 +578,6 @@ struct spi_nor {
>  	int (*flash_lock)(struct spi_nor *nor, loff_t ofs, uint64_t len);
>  	int (*flash_unlock)(struct spi_nor *nor, loff_t ofs, uint64_t len);
>  	int (*flash_is_locked)(struct spi_nor *nor, loff_t ofs, uint64_t len);
> -	int (*clear_sr_bp)(struct spi_nor *nor);
>  	struct spi_nor_flash_parameter params;
>  
>  	void *priv;
Ambarus Tudor Aug. 25, 2019, 1:19 p.m. UTC | #4
On 08/25/2019 04:09 PM, Boris Brezillon wrote:
> On Fri, 23 Aug 2019 15:53:41 +0000
> <Tudor.Ambarus@microchip.com> wrote:
> 
>> From: Tudor Ambarus <tudor.ambarus@microchip.com>
>>
>> All flash parameters and settings should reside inside
>> 'struct spi_nor_flash_parameter'. Move clear_sr_bp() from
>> 'struct spi_nor' to 'struct spi_nor_flash_parameter'.
>>
>> Rename clear_sr_bp()/disable_block_protection() to better indicate
>> what the function does.
>>
>> Signed-off-by: Tudor Ambarus <tudor.ambarus@microchip.com>
>> ---
>>  drivers/mtd/spi-nor/spi-nor.c | 47 +++++++++++++++++++++++++++++++++----------
>>  include/linux/mtd/spi-nor.h   |  5 ++---
>>  2 files changed, 38 insertions(+), 14 deletions(-)
>>
>> diff --git a/drivers/mtd/spi-nor/spi-nor.c b/drivers/mtd/spi-nor/spi-nor.c
>> index 6bd104c29cd9..15b0b1148bf3 100644
>> --- a/drivers/mtd/spi-nor/spi-nor.c
>> +++ b/drivers/mtd/spi-nor/spi-nor.c
>> @@ -4477,20 +4477,45 @@ static int spi_nor_quad_enable(struct spi_nor *nor)
>>  	return nor->params.quad_enable(nor);
>>  }
>>  
>> +/**
>> + * spi_nor_disable_block_protection() - Disable the write block protection
>> + * during power-up.
>> + * @nor:                pointer to a 'struct spi_nor'
>> + *
>> + * Some spi-nor flashes are write protected by default after a power-on reset
>> + * cycle, in order to avoid inadvertend writes during power-up. Backward
>> + * compatibility imposes to disable the write block protection at power-up
>> + * by default.
>> + *
>> + * Return: 0 on success, -errno otherwise.
>> + */
>> +static int spi_nor_disable_block_protection(struct spi_nor *nor)
>> +{
>> +	if (!nor->params.disable_block_protection)
>> +		return 0;
>> +
>> +	/*
>> +	 * In case of the legacy quad enable requirements are set, if the
>> +	 * configuration register Quad Enable bit is one, only the the
>> +	 * Write Status (01h) command with two data bytes may be used to clear
>> +	 * the block protection bits.
>> +	 */
>> +	if (nor->params.quad_enable == spansion_quad_enable)
>> +		nor->params.disable_block_protection =
>> +			spi_nor_spansion_clear_sr_bp;
> 
> Hm, doesn't look right to adjust the function pointer just before
> calling it. Can't we move that logic earlier (when doing the
> default/manufacturer specific init)? Also, as I said in one of my

No, we can't move it earlier to ->default_init() because the pointer to
quad_enable() function can be modified later on, when parsing SFDP. This should
stay here, after the quad_enable() method is known, so after the
spi_nor_init_params() call.


> previous emails, I'd prefer to have this hook moved to
> spi_nor_locking_ops and just have a flag to reflect when block
> protection can be disabled.

yes, I agree, will move.

> 
>> +
>> +	return nor->params.disable_block_protection(nor);
>> +}
>> +
>>  static int spi_nor_init(struct spi_nor *nor)
>>  {
>>  	int err;
>>  
>> -	if (nor->clear_sr_bp) {
>> -		if (nor->quad_enable == spansion_quad_enable)
>> -			nor->clear_sr_bp = spi_nor_spansion_clear_sr_bp;
>> -
>> -		err = nor->clear_sr_bp(nor);
>> -		if (err) {
>> -			dev_err(nor->dev,
>> -				"fail to clear block protection bits\n");
>> -			return err;
>> -		}
>> +	err = spi_nor_disable_block_protection(nor);
>> +	if (err) {
>> +		dev_err(nor->dev,
>> +			"fail to unlock the flash at init (err = %d)\n", err);
>> +		return err;
>>  	}
>>  
>>  	err = spi_nor_quad_enable(nor);
>> @@ -4635,7 +4660,7 @@ int spi_nor_scan(struct spi_nor *nor, const char *name,
>>  	    JEDEC_MFR(nor->info) == SNOR_MFR_INTEL ||
>>  	    JEDEC_MFR(nor->info) == SNOR_MFR_SST ||
>>  	    nor->info->flags & SPI_NOR_HAS_LOCK)
>> -		nor->clear_sr_bp = spi_nor_clear_sr_bp;
>> +		nor->params.disable_block_protection = spi_nor_clear_sr_bp;
>>  
>>  	/* Parse the Serial Flash Discoverable Parameters table. */
>>  	ret = spi_nor_init_params(nor);
>> diff --git a/include/linux/mtd/spi-nor.h b/include/linux/mtd/spi-nor.h
>> index 17787238f0e9..399ac34a529d 100644
>> --- a/include/linux/mtd/spi-nor.h
>> +++ b/include/linux/mtd/spi-nor.h
>> @@ -480,6 +480,7 @@ struct spi_nor;
>>   * @page_programs:	page program capabilities ordered by priority: the
>>   *                      higher index in the array, the higher priority.
>>   * @quad_enable:	enables SPI NOR quad mode.
>> + * @disable_block_protection: disables block protection during power-up.
>>   */
>>  struct spi_nor_flash_parameter {
>>  	u64				size;
>> @@ -490,6 +491,7 @@ struct spi_nor_flash_parameter {
>>  	struct spi_nor_pp_command	page_programs[SNOR_CMD_PP_MAX];
>>  
>>  	int (*quad_enable)(struct spi_nor *nor);
>> +	int (*disable_block_protection)(struct spi_nor *nor);
>>  };
>>  
>>  /**
>> @@ -535,8 +537,6 @@ struct flash_info;
>>   * @flash_unlock:	[FLASH-SPECIFIC] unlock a region of the SPI NOR
>>   * @flash_is_locked:	[FLASH-SPECIFIC] check if a region of the SPI NOR is
>>   *			completely locked
>> - * @clear_sr_bp:	[FLASH-SPECIFIC] clears the Block Protection Bits from
>> - *			the SPI NOR Status Register.
>>   * @params:		[FLASH-SPECIFIC] SPI-NOR flash parameters and settings.
>>   *                      The structure includes legacy flash parameters and
>>   *                      settings that can be overwritten by the spi_nor_fixups
>> @@ -578,7 +578,6 @@ struct spi_nor {
>>  	int (*flash_lock)(struct spi_nor *nor, loff_t ofs, uint64_t len);
>>  	int (*flash_unlock)(struct spi_nor *nor, loff_t ofs, uint64_t len);
>>  	int (*flash_is_locked)(struct spi_nor *nor, loff_t ofs, uint64_t len);
>> -	int (*clear_sr_bp)(struct spi_nor *nor);
>>  	struct spi_nor_flash_parameter params;
>>  
>>  	void *priv;
> 
>
Boris Brezillon Aug. 25, 2019, 1:28 p.m. UTC | #5
On Sun, 25 Aug 2019 13:19:57 +0000
<Tudor.Ambarus@microchip.com> wrote:

> On 08/25/2019 04:09 PM, Boris Brezillon wrote:
> > On Fri, 23 Aug 2019 15:53:41 +0000
> > <Tudor.Ambarus@microchip.com> wrote:
> >   
> >> From: Tudor Ambarus <tudor.ambarus@microchip.com>
> >>
> >> All flash parameters and settings should reside inside
> >> 'struct spi_nor_flash_parameter'. Move clear_sr_bp() from
> >> 'struct spi_nor' to 'struct spi_nor_flash_parameter'.
> >>
> >> Rename clear_sr_bp()/disable_block_protection() to better indicate
> >> what the function does.
> >>
> >> Signed-off-by: Tudor Ambarus <tudor.ambarus@microchip.com>
> >> ---
> >>  drivers/mtd/spi-nor/spi-nor.c | 47 +++++++++++++++++++++++++++++++++----------
> >>  include/linux/mtd/spi-nor.h   |  5 ++---
> >>  2 files changed, 38 insertions(+), 14 deletions(-)
> >>
> >> diff --git a/drivers/mtd/spi-nor/spi-nor.c b/drivers/mtd/spi-nor/spi-nor.c
> >> index 6bd104c29cd9..15b0b1148bf3 100644
> >> --- a/drivers/mtd/spi-nor/spi-nor.c
> >> +++ b/drivers/mtd/spi-nor/spi-nor.c
> >> @@ -4477,20 +4477,45 @@ static int spi_nor_quad_enable(struct spi_nor *nor)
> >>  	return nor->params.quad_enable(nor);
> >>  }
> >>  
> >> +/**
> >> + * spi_nor_disable_block_protection() - Disable the write block protection
> >> + * during power-up.
> >> + * @nor:                pointer to a 'struct spi_nor'
> >> + *
> >> + * Some spi-nor flashes are write protected by default after a power-on reset
> >> + * cycle, in order to avoid inadvertend writes during power-up. Backward
> >> + * compatibility imposes to disable the write block protection at power-up
> >> + * by default.
> >> + *
> >> + * Return: 0 on success, -errno otherwise.
> >> + */
> >> +static int spi_nor_disable_block_protection(struct spi_nor *nor)
> >> +{
> >> +	if (!nor->params.disable_block_protection)
> >> +		return 0;
> >> +
> >> +	/*
> >> +	 * In case of the legacy quad enable requirements are set, if the
> >> +	 * configuration register Quad Enable bit is one, only the the
> >> +	 * Write Status (01h) command with two data bytes may be used to clear
> >> +	 * the block protection bits.
> >> +	 */
> >> +	if (nor->params.quad_enable == spansion_quad_enable)
> >> +		nor->params.disable_block_protection =
> >> +			spi_nor_spansion_clear_sr_bp;  
> > 
> > Hm, doesn't look right to adjust the function pointer just before
> > calling it. Can't we move that logic earlier (when doing the
> > default/manufacturer specific init)? Also, as I said in one of my  
> 
> No, we can't move it earlier to ->default_init() because the pointer to
> quad_enable() function can be modified later on, when parsing SFDP. This should
> stay here, after the quad_enable() method is known, so after the
> spi_nor_init_params() call.
> 
> 
> > previous emails, I'd prefer to have this hook moved to
> > spi_nor_locking_ops and just have a flag to reflect when block
> > protection can be disabled.  
> 
> yes, I agree, will move.

That won't work: ->locking_ops is const, meaning that you can't update
individual fields (which I consider a good thing). As I see it, the
locking scheme is a package that describe how to lock/unlock blocks, be
it individually, by groups or globally. I really hope we can take this
decision on a per-manufacturer basis, but I fear it might actually be a
per-chip thing.

> 
> >   
> >> +
> >> +	return nor->params.disable_block_protection(nor);
> >> +}
> >> +
> >>  static int spi_nor_init(struct spi_nor *nor)
> >>  {
> >>  	int err;
> >>  
> >> -	if (nor->clear_sr_bp) {
> >> -		if (nor->quad_enable == spansion_quad_enable)
> >> -			nor->clear_sr_bp = spi_nor_spansion_clear_sr_bp;
> >> -
> >> -		err = nor->clear_sr_bp(nor);
> >> -		if (err) {
> >> -			dev_err(nor->dev,
> >> -				"fail to clear block protection bits\n");
> >> -			return err;
> >> -		}
> >> +	err = spi_nor_disable_block_protection(nor);
> >> +	if (err) {
> >> +		dev_err(nor->dev,
> >> +			"fail to unlock the flash at init (err = %d)\n", err);
> >> +		return err;
> >>  	}
> >>  
> >>  	err = spi_nor_quad_enable(nor);
> >> @@ -4635,7 +4660,7 @@ int spi_nor_scan(struct spi_nor *nor, const char *name,
> >>  	    JEDEC_MFR(nor->info) == SNOR_MFR_INTEL ||
> >>  	    JEDEC_MFR(nor->info) == SNOR_MFR_SST ||
> >>  	    nor->info->flags & SPI_NOR_HAS_LOCK)
> >> -		nor->clear_sr_bp = spi_nor_clear_sr_bp;
> >> +		nor->params.disable_block_protection = spi_nor_clear_sr_bp;
> >>  
> >>  	/* Parse the Serial Flash Discoverable Parameters table. */
> >>  	ret = spi_nor_init_params(nor);
> >> diff --git a/include/linux/mtd/spi-nor.h b/include/linux/mtd/spi-nor.h
> >> index 17787238f0e9..399ac34a529d 100644
> >> --- a/include/linux/mtd/spi-nor.h
> >> +++ b/include/linux/mtd/spi-nor.h
> >> @@ -480,6 +480,7 @@ struct spi_nor;
> >>   * @page_programs:	page program capabilities ordered by priority: the
> >>   *                      higher index in the array, the higher priority.
> >>   * @quad_enable:	enables SPI NOR quad mode.
> >> + * @disable_block_protection: disables block protection during power-up.
> >>   */
> >>  struct spi_nor_flash_parameter {
> >>  	u64				size;
> >> @@ -490,6 +491,7 @@ struct spi_nor_flash_parameter {
> >>  	struct spi_nor_pp_command	page_programs[SNOR_CMD_PP_MAX];
> >>  
> >>  	int (*quad_enable)(struct spi_nor *nor);
> >> +	int (*disable_block_protection)(struct spi_nor *nor);
> >>  };
> >>  
> >>  /**
> >> @@ -535,8 +537,6 @@ struct flash_info;
> >>   * @flash_unlock:	[FLASH-SPECIFIC] unlock a region of the SPI NOR
> >>   * @flash_is_locked:	[FLASH-SPECIFIC] check if a region of the SPI NOR is
> >>   *			completely locked
> >> - * @clear_sr_bp:	[FLASH-SPECIFIC] clears the Block Protection Bits from
> >> - *			the SPI NOR Status Register.
> >>   * @params:		[FLASH-SPECIFIC] SPI-NOR flash parameters and settings.
> >>   *                      The structure includes legacy flash parameters and
> >>   *                      settings that can be overwritten by the spi_nor_fixups
> >> @@ -578,7 +578,6 @@ struct spi_nor {
> >>  	int (*flash_lock)(struct spi_nor *nor, loff_t ofs, uint64_t len);
> >>  	int (*flash_unlock)(struct spi_nor *nor, loff_t ofs, uint64_t len);
> >>  	int (*flash_is_locked)(struct spi_nor *nor, loff_t ofs, uint64_t len);
> >> -	int (*clear_sr_bp)(struct spi_nor *nor);
> >>  	struct spi_nor_flash_parameter params;
> >>  
> >>  	void *priv;  
> > 
> >

Patch
diff mbox series

diff --git a/drivers/mtd/spi-nor/spi-nor.c b/drivers/mtd/spi-nor/spi-nor.c
index 6bd104c29cd9..15b0b1148bf3 100644
--- a/drivers/mtd/spi-nor/spi-nor.c
+++ b/drivers/mtd/spi-nor/spi-nor.c
@@ -4477,20 +4477,45 @@  static int spi_nor_quad_enable(struct spi_nor *nor)
 	return nor->params.quad_enable(nor);
 }
 
+/**
+ * spi_nor_disable_block_protection() - Disable the write block protection
+ * during power-up.
+ * @nor:                pointer to a 'struct spi_nor'
+ *
+ * Some spi-nor flashes are write protected by default after a power-on reset
+ * cycle, in order to avoid inadvertend writes during power-up. Backward
+ * compatibility imposes to disable the write block protection at power-up
+ * by default.
+ *
+ * Return: 0 on success, -errno otherwise.
+ */
+static int spi_nor_disable_block_protection(struct spi_nor *nor)
+{
+	if (!nor->params.disable_block_protection)
+		return 0;
+
+	/*
+	 * In case of the legacy quad enable requirements are set, if the
+	 * configuration register Quad Enable bit is one, only the the
+	 * Write Status (01h) command with two data bytes may be used to clear
+	 * the block protection bits.
+	 */
+	if (nor->params.quad_enable == spansion_quad_enable)
+		nor->params.disable_block_protection =
+			spi_nor_spansion_clear_sr_bp;
+
+	return nor->params.disable_block_protection(nor);
+}
+
 static int spi_nor_init(struct spi_nor *nor)
 {
 	int err;
 
-	if (nor->clear_sr_bp) {
-		if (nor->quad_enable == spansion_quad_enable)
-			nor->clear_sr_bp = spi_nor_spansion_clear_sr_bp;
-
-		err = nor->clear_sr_bp(nor);
-		if (err) {
-			dev_err(nor->dev,
-				"fail to clear block protection bits\n");
-			return err;
-		}
+	err = spi_nor_disable_block_protection(nor);
+	if (err) {
+		dev_err(nor->dev,
+			"fail to unlock the flash at init (err = %d)\n", err);
+		return err;
 	}
 
 	err = spi_nor_quad_enable(nor);
@@ -4635,7 +4660,7 @@  int spi_nor_scan(struct spi_nor *nor, const char *name,
 	    JEDEC_MFR(nor->info) == SNOR_MFR_INTEL ||
 	    JEDEC_MFR(nor->info) == SNOR_MFR_SST ||
 	    nor->info->flags & SPI_NOR_HAS_LOCK)
-		nor->clear_sr_bp = spi_nor_clear_sr_bp;
+		nor->params.disable_block_protection = spi_nor_clear_sr_bp;
 
 	/* Parse the Serial Flash Discoverable Parameters table. */
 	ret = spi_nor_init_params(nor);
diff --git a/include/linux/mtd/spi-nor.h b/include/linux/mtd/spi-nor.h
index 17787238f0e9..399ac34a529d 100644
--- a/include/linux/mtd/spi-nor.h
+++ b/include/linux/mtd/spi-nor.h
@@ -480,6 +480,7 @@  struct spi_nor;
  * @page_programs:	page program capabilities ordered by priority: the
  *                      higher index in the array, the higher priority.
  * @quad_enable:	enables SPI NOR quad mode.
+ * @disable_block_protection: disables block protection during power-up.
  */
 struct spi_nor_flash_parameter {
 	u64				size;
@@ -490,6 +491,7 @@  struct spi_nor_flash_parameter {
 	struct spi_nor_pp_command	page_programs[SNOR_CMD_PP_MAX];
 
 	int (*quad_enable)(struct spi_nor *nor);
+	int (*disable_block_protection)(struct spi_nor *nor);
 };
 
 /**
@@ -535,8 +537,6 @@  struct flash_info;
  * @flash_unlock:	[FLASH-SPECIFIC] unlock a region of the SPI NOR
  * @flash_is_locked:	[FLASH-SPECIFIC] check if a region of the SPI NOR is
  *			completely locked
- * @clear_sr_bp:	[FLASH-SPECIFIC] clears the Block Protection Bits from
- *			the SPI NOR Status Register.
  * @params:		[FLASH-SPECIFIC] SPI-NOR flash parameters and settings.
  *                      The structure includes legacy flash parameters and
  *                      settings that can be overwritten by the spi_nor_fixups
@@ -578,7 +578,6 @@  struct spi_nor {
 	int (*flash_lock)(struct spi_nor *nor, loff_t ofs, uint64_t len);
 	int (*flash_unlock)(struct spi_nor *nor, loff_t ofs, uint64_t len);
 	int (*flash_is_locked)(struct spi_nor *nor, loff_t ofs, uint64_t len);
-	int (*clear_sr_bp)(struct spi_nor *nor);
 	struct spi_nor_flash_parameter params;
 
 	void *priv;