[PATCH v5] spi: spi-mem: Adjust op len based on message/transfer size limitations

[PATCH v5] spi: spi-mem: Adjust op len based on message/transfer size limitations

[Chuanhua Han]

We need that to adjust the len of the 2nd transfer (called data in spi-mem)
if it's too long to fit in a SPI message or SPI transfer.

Fixes: c36ff266dc82 ("spi: Extend the core to ease integration of SPI memory controllers")
Cc: <stable@vger.kernel.org>
Signed-off-by: Chuanhua Han <chuanhua.han@nxp.com>
Suggested-by: Boris Brezillon <boris.brezillon@bootlin.com>
---
Changes in v5:
  -Add the validation check after the op->data.nbytes assignment
  -Assign the "len" variable after defining it
  -Remove the brackets on both sides of "opt-> data.nbytes"
Changes in v4:
  -Rename variable name "opcode_addr_dummy_sum" to "len".
  -The comparison of "spi_max_message_size(mem->spi)" and "len" was removed.
  -Adjust their order when comparing the sizes of "spi_max_message_size(mem->spi)" and "len"
  -Changing the "unsigned long" type in the code to "size_t"
Changes in v3:
  -Rename variable name "val" to "opcode_addr_dummy_sum".
  -Place the legitimacy of the transfer size(i.e., "spi_max_message_size(mem->spi)" and
  -"opcode_addr_dummy_sum") into "if (! ctlr - > mem_ops | |! ctlr-> mem_ops->exec_op) {"
structure and add "spi_max_transfer_size(mem->spi) and opcode_addr_dummy_sum".
  -Adjust the formatting alignment of the code.
  -"(unsigned long)op->data.nbytes" was modified to "(unsigned long)(op->data.nbytes)".
Changes in v2:
  -Place the adjusted transfer bytes code in spi_mem_adjust_op_size() and  check
spi_max_message_size(mem->spi) value before subtracting opcode, addr and dummy bytes.
  -Change the code from fsl-espi controller to generic code(The adjustment of spi transmission
length was originally modified in the "drivers/spi/spi-fsl-espi.c" file, and now the adjustment
of transfer length is made in the "drivers/spi/spi-mem.c" file)

 drivers/spi/spi-mem.c | 16 ++++++++++++++++
 1 file changed, 16 insertions(+)

diff --git a/drivers/spi/spi-mem.c b/drivers/spi/spi-mem.c
index 990770d..6184fa1 100644
--- a/drivers/spi/spi-mem.c
+++ b/drivers/spi/spi-mem.c
@@ -328,10 +328,26 @@ EXPORT_SYMBOL_GPL(spi_mem_exec_op);
 int spi_mem_adjust_op_size(struct spi_mem *mem, struct spi_mem_op *op)
 {
 	struct spi_controller *ctlr = mem->spi->controller;
+	size_t len;
+
+	len = sizeof(op->cmd.opcode) + op->addr.nbytes + op->dummy.nbytes;
 
 	if (ctlr->mem_ops && ctlr->mem_ops->adjust_op_size)
 		return ctlr->mem_ops->adjust_op_size(mem, op);
 
+	if (!ctlr->mem_ops || !ctlr->mem_ops->exec_op) {
+		if (len > spi_max_transfer_size(mem->spi))
+			return -EINVAL;
+
+		op->data.nbytes = min3((size_t)op->data.nbytes,
+				       spi_max_transfer_size(mem->spi),
+				       spi_max_message_size(mem->spi) -
+				       len);
+
+		if (!op->data.nbytes)
+			return -EINVAL;
+	}
+
 	return 0;
 }
 EXPORT_SYMBOL_GPL(spi_mem_adjust_op_size);
-- 
2.7.4

RE: [PATCH v5] spi: spi-mem: Adjust op len based on message/transfer size limitations

[Chuanhua Han]

> -----Original Message-----
> From: Boris Brezillon <boris.brezillon@bootlin.com>
> Sent: 2018年8月30日 17:17
> To: Chuanhua Han <chuanhua.han@nxp.com>
> Cc: broonie@kernel.org; linux-spi@vger.kernel.org;
> linux-kernel@vger.kernel.org; stable@vger.kernel.org
> Subject: Re: [PATCH v5] spi: spi-mem: Adjust op len based on message/transfer
> size limitations
> 
> On Thu, 30 Aug 2018 09:13:03 +0000
> Chuanhua Han <chuanhua.han@nxp.com> wrote:
> 
> > > -----Original Message-----
> > > From: Boris Brezillon <boris.brezillon@bootlin.com>
> > > Sent: 2018年8月30日 16:47
> > > To: Chuanhua Han <chuanhua.han@nxp.com>
> > > Cc: broonie@kernel.org; linux-spi@vger.kernel.org;
> > > linux-kernel@vger.kernel.org; stable@vger.kernel.org
> > > Subject: Re: [PATCH v5] spi: spi-mem: Adjust op len based on
> > > message/transfer size limitations
> > >
> > > Hi Chuanhua,
> > >
> > > On Thu, 30 Aug 2018 16:43:24 +0800
> > > Chuanhua Han <chuanhua.han@nxp.com> wrote:
> > >
> > > > We need that to adjust the len of the 2nd transfer (called data in
> > > > spi-mem) if it's too long to fit in a SPI message or SPI transfer.
> > >
> > > You already sent this email a few days back. Please wait a bit
> > > before sending it again. And when you do so and nothing changed in
> > > the patch please use the [PATCH RESEND vX] prefix and explain why you
> resend it.
> > I have modified the patch for the comment you mentioned last time. Do
> > you need any other modification？
> 
> Oops, sorry. Looks like the previous one was only sent to me, not the ML and
> the SPI maintainer.
It doesn't matter，thank you for your valuable advice！

Re: [PATCH v5] spi: spi-mem: Adjust op len based on message/transfer size limitations

[Boris Brezillon]

On Thu, 30 Aug 2018 09:13:03 +0000
Chuanhua Han <chuanhua.han@nxp.com> wrote:

> > -----Original Message-----
> > From: Boris Brezillon <boris.brezillon@bootlin.com>
> > Sent: 2018年8月30日 16:47
> > To: Chuanhua Han <chuanhua.han@nxp.com>
> > Cc: broonie@kernel.org; linux-spi@vger.kernel.org;
> > linux-kernel@vger.kernel.org; stable@vger.kernel.org
> > Subject: Re: [PATCH v5] spi: spi-mem: Adjust op len based on message/transfer
> > size limitations
> > 
> > Hi Chuanhua,
> > 
> > On Thu, 30 Aug 2018 16:43:24 +0800
> > Chuanhua Han <chuanhua.han@nxp.com> wrote:
> >   
> > > We need that to adjust the len of the 2nd transfer (called data in
> > > spi-mem) if it's too long to fit in a SPI message or SPI transfer.  
> > 
> > You already sent this email a few days back. Please wait a bit before sending it
> > again. And when you do so and nothing changed in the patch please use the
> > [PATCH RESEND vX] prefix and explain why you resend it.  
> I have modified the patch for the comment you mentioned last time. Do you need any other modification？

Oops, sorry. Looks like the previous one was only sent to me, not the
ML and the SPI maintainer.

RE: [PATCH v5] spi: spi-mem: Adjust op len based on message/transfer size limitations

[Chuanhua Han]

> -----Original Message-----
> From: Boris Brezillon <boris.brezillon@bootlin.com>
> Sent: 2018年8月30日 16:47
> To: Chuanhua Han <chuanhua.han@nxp.com>
> Cc: broonie@kernel.org; linux-spi@vger.kernel.org;
> linux-kernel@vger.kernel.org; stable@vger.kernel.org
> Subject: Re: [PATCH v5] spi: spi-mem: Adjust op len based on message/transfer
> size limitations
> 
> Hi Chuanhua,
> 
> On Thu, 30 Aug 2018 16:43:24 +0800
> Chuanhua Han <chuanhua.han@nxp.com> wrote:
> 
> > We need that to adjust the len of the 2nd transfer (called data in
> > spi-mem) if it's too long to fit in a SPI message or SPI transfer.
> 
> You already sent this email a few days back. Please wait a bit before sending it
> again. And when you do so and nothing changed in the patch please use the
> [PATCH RESEND vX] prefix and explain why you resend it.
I have modified the patch for the comment you mentioned last time. Do you need any other modification？
> 
> Thanks,
> 
> Boris
> 
> >
> > Fixes: c36ff266dc82 ("spi: Extend the core to ease integration of SPI
> > memory controllers")
> > Cc: <stable@vger.kernel.org>
> > Signed-off-by: Chuanhua Han <chuanhua.han@nxp.com>
> > Reviewed-by: Boris Brezillon <boris.brezillon@bootlin.com>
> > ---
> > Changes in v5:
> >   -Add the validation check after the op->data.nbytes assignment
> >   -Assign the "len" variable after defining it
> >   -Remove the brackets on both sides of "opt-> data.nbytes"
> > Changes in v4:
> >   -Rename variable name "opcode_addr_dummy_sum" to "len"
> >   -The comparison of "spi_max_message_size(mem->spi)" and "len" was
> removed
> >   -Adjust their order when comparing the sizes of
> "spi_max_message_size(mem->spi)" and "len"
> >   -Changing the "unsigned long" type in the code to "size_t"
> > Changes in v3:
> >   -Rename variable name "val" to "opcode_addr_dummy_sum"
> >   -Place the legitimacy of the transfer size(i.e.,
> > "spi_max_message_size(mem->spi)" and
> > "opcode_addr_dummy_sum") into "if (! ctlr - > mem_ops | |! ctlr->
> mem_ops->exec_op) {"
> > structure and add "spi_max_transfer_size(mem->spi) and
> opcode_addr_dummy_sum"
> >   -Adjust the formatting alignment of the code
> >   -"(unsigned long)op->data.nbytes" was modified to "(unsigned
> long)(op->data.nbytes)"
> > Changes in v2:
> >   -Place the adjusted transfer bytes code in spi_mem_adjust_op_size()
> > and  check
> > spi_max_message_size(mem->spi) value before subtracting opcode, addr and
> dummy bytes
> >   -Change the code from fsl-espi controller to generic code(The
> > adjustment of spi transmission length was originally modified in the
> > "drivers/spi/spi-fsl-espi.c" file, and now the adjustment of transfer
> > length is made in the "drivers/spi/spi-mem.c" file)
> >
> >  drivers/spi/spi-mem.c | 15 +++++++++++++++
> >  1 file changed, 15 insertions(+)
> >
> > diff --git a/drivers/spi/spi-mem.c b/drivers/spi/spi-mem.c index
> > e43842c..eb72dba 100644
> > --- a/drivers/spi/spi-mem.c
> > +++ b/drivers/spi/spi-mem.c
> > @@ -346,10 +346,25 @@ EXPORT_SYMBOL_GPL(spi_mem_get_name);
> >  int spi_mem_adjust_op_size(struct spi_mem *mem, struct spi_mem_op
> > *op)  {
> >  	struct spi_controller *ctlr = mem->spi->controller;
> > +	size_t len;
> > +
> > +	len = sizeof(op->cmd.opcode) + op->addr.nbytes + op->dummy.nbytes;
> >
> >  	if (ctlr->mem_ops && ctlr->mem_ops->adjust_op_size)
> >  		return ctlr->mem_ops->adjust_op_size(mem, op);
> >
> > +	if (!ctlr->mem_ops || !ctlr->mem_ops->exec_op) {
> > +		if (len > spi_max_transfer_size(mem->spi))
> > +			return -EINVAL;
> > +
> > +		op->data.nbytes = min3((size_t)op->data.nbytes,
> > +				       spi_max_transfer_size(mem->spi),
> > +				       spi_max_message_size(mem->spi) -
> > +				       len);
> > +		if (!op->data.nbytes)
> > +			return -EINVAL;
> > +	}
> > +
> >  	return 0;
> >  }
> >  EXPORT_SYMBOL_GPL(spi_mem_adjust_op_size);

Re: [PATCH v5] spi: spi-mem: Adjust op len based on message/transfer size limitations

[Boris Brezillon]

Hi Chuanhua,

On Thu, 30 Aug 2018 16:43:24 +0800
Chuanhua Han <chuanhua.han@nxp.com> wrote:

> We need that to adjust the len of the 2nd transfer (called data in
> spi-mem) if it's too long to fit in a SPI message or SPI transfer.

You already sent this email a few days back. Please wait a bit before
sending it again. And when you do so and nothing changed in the patch
please use the [PATCH RESEND vX] prefix and explain why you resend it.

Thanks,

Boris

> 
> Fixes: c36ff266dc82 ("spi: Extend the core to ease integration of SPI memory controllers")
> Cc: <stable@vger.kernel.org>
> Signed-off-by: Chuanhua Han <chuanhua.han@nxp.com>
> Reviewed-by: Boris Brezillon <boris.brezillon@bootlin.com>
> ---
> Changes in v5:
>   -Add the validation check after the op->data.nbytes assignment
>   -Assign the "len" variable after defining it
>   -Remove the brackets on both sides of "opt-> data.nbytes"
> Changes in v4:
>   -Rename variable name "opcode_addr_dummy_sum" to "len"
>   -The comparison of "spi_max_message_size(mem->spi)" and "len" was removed
>   -Adjust their order when comparing the sizes of "spi_max_message_size(mem->spi)" and "len"
>   -Changing the "unsigned long" type in the code to "size_t"
> Changes in v3:
>   -Rename variable name "val" to "opcode_addr_dummy_sum"
>   -Place the legitimacy of the transfer size(i.e., "spi_max_message_size(mem->spi)" and
> "opcode_addr_dummy_sum") into "if (! ctlr - > mem_ops | |! ctlr-> mem_ops->exec_op) {"
> structure and add "spi_max_transfer_size(mem->spi) and opcode_addr_dummy_sum"
>   -Adjust the formatting alignment of the code
>   -"(unsigned long)op->data.nbytes" was modified to "(unsigned long)(op->data.nbytes)"
> Changes in v2:
>   -Place the adjusted transfer bytes code in spi_mem_adjust_op_size() and  check
> spi_max_message_size(mem->spi) value before subtracting opcode, addr and dummy bytes
>   -Change the code from fsl-espi controller to generic code(The adjustment of spi transmission
> length was originally modified in the "drivers/spi/spi-fsl-espi.c" file, and now the adjustment
> of transfer length is made in the "drivers/spi/spi-mem.c" file)
> 
>  drivers/spi/spi-mem.c | 15 +++++++++++++++
>  1 file changed, 15 insertions(+)
> 
> diff --git a/drivers/spi/spi-mem.c b/drivers/spi/spi-mem.c
> index e43842c..eb72dba 100644
> --- a/drivers/spi/spi-mem.c
> +++ b/drivers/spi/spi-mem.c
> @@ -346,10 +346,25 @@ EXPORT_SYMBOL_GPL(spi_mem_get_name);
>  int spi_mem_adjust_op_size(struct spi_mem *mem, struct spi_mem_op *op)
>  {
>  	struct spi_controller *ctlr = mem->spi->controller;
> +	size_t len;
> +
> +	len = sizeof(op->cmd.opcode) + op->addr.nbytes + op->dummy.nbytes;
>  
>  	if (ctlr->mem_ops && ctlr->mem_ops->adjust_op_size)
>  		return ctlr->mem_ops->adjust_op_size(mem, op);
>  
> +	if (!ctlr->mem_ops || !ctlr->mem_ops->exec_op) {
> +		if (len > spi_max_transfer_size(mem->spi))
> +			return -EINVAL;
> +
> +		op->data.nbytes = min3((size_t)op->data.nbytes,
> +				       spi_max_transfer_size(mem->spi),
> +				       spi_max_message_size(mem->spi) -
> +				       len);
> +		if (!op->data.nbytes)
> +			return -EINVAL;
> +	}
> +
>  	return 0;
>  }
>  EXPORT_SYMBOL_GPL(spi_mem_adjust_op_size);

[PATCH v5] spi: spi-mem: Adjust op len based on message/transfer size limitations

[Chuanhua Han]

We need that to adjust the len of the 2nd transfer (called data in
spi-mem) if it's too long to fit in a SPI message or SPI transfer.

Fixes: c36ff266dc82 ("spi: Extend the core to ease integration of SPI memory controllers")
Cc: <stable@vger.kernel.org>
Signed-off-by: Chuanhua Han <chuanhua.han@nxp.com>
Reviewed-by: Boris Brezillon <boris.brezillon@bootlin.com>
---
Changes in v5:
  -Add the validation check after the op->data.nbytes assignment
  -Assign the "len" variable after defining it
  -Remove the brackets on both sides of "opt-> data.nbytes"
Changes in v4:
  -Rename variable name "opcode_addr_dummy_sum" to "len"
  -The comparison of "spi_max_message_size(mem->spi)" and "len" was removed
  -Adjust their order when comparing the sizes of "spi_max_message_size(mem->spi)" and "len"
  -Changing the "unsigned long" type in the code to "size_t"
Changes in v3:
  -Rename variable name "val" to "opcode_addr_dummy_sum"
  -Place the legitimacy of the transfer size(i.e., "spi_max_message_size(mem->spi)" and
"opcode_addr_dummy_sum") into "if (! ctlr - > mem_ops | |! ctlr-> mem_ops->exec_op) {"
structure and add "spi_max_transfer_size(mem->spi) and opcode_addr_dummy_sum"
  -Adjust the formatting alignment of the code
  -"(unsigned long)op->data.nbytes" was modified to "(unsigned long)(op->data.nbytes)"
Changes in v2:
  -Place the adjusted transfer bytes code in spi_mem_adjust_op_size() and  check
spi_max_message_size(mem->spi) value before subtracting opcode, addr and dummy bytes
  -Change the code from fsl-espi controller to generic code(The adjustment of spi transmission
length was originally modified in the "drivers/spi/spi-fsl-espi.c" file, and now the adjustment
of transfer length is made in the "drivers/spi/spi-mem.c" file)

 drivers/spi/spi-mem.c | 15 +++++++++++++++
 1 file changed, 15 insertions(+)

diff --git a/drivers/spi/spi-mem.c b/drivers/spi/spi-mem.c
index e43842c..eb72dba 100644
--- a/drivers/spi/spi-mem.c
+++ b/drivers/spi/spi-mem.c
@@ -346,10 +346,25 @@ EXPORT_SYMBOL_GPL(spi_mem_get_name);
 int spi_mem_adjust_op_size(struct spi_mem *mem, struct spi_mem_op *op)
 {
 	struct spi_controller *ctlr = mem->spi->controller;
+	size_t len;
+
+	len = sizeof(op->cmd.opcode) + op->addr.nbytes + op->dummy.nbytes;
 
 	if (ctlr->mem_ops && ctlr->mem_ops->adjust_op_size)
 		return ctlr->mem_ops->adjust_op_size(mem, op);
 
+	if (!ctlr->mem_ops || !ctlr->mem_ops->exec_op) {
+		if (len > spi_max_transfer_size(mem->spi))
+			return -EINVAL;
+
+		op->data.nbytes = min3((size_t)op->data.nbytes,
+				       spi_max_transfer_size(mem->spi),
+				       spi_max_message_size(mem->spi) -
+				       len);
+		if (!op->data.nbytes)
+			return -EINVAL;
+	}
+
 	return 0;
 }
 EXPORT_SYMBOL_GPL(spi_mem_adjust_op_size);
-- 
2.7.4

[PATCH v5] spi: spi-mem: Adjust op len based on message/transfer size limitations

[Chuanhua Han]

We need that to adjust the len of the 2nd transfer (called data in 
spi-mem) if it's too long to fit in a SPI message or SPI transfer.

Fixes: c36ff266dc82 ("spi: Extend the core to ease integration of SPI memory controllers")
Cc: <stable@vger.kernel.org>
Signed-off-by: Chuanhua Han <chuanhua.han@nxp.com>
Suggested-by: Boris Brezillon <boris.brezillon@bootlin.com>
---
Changes in v5:
  -Add the validation check after the op->data.nbytes assignment
  -Assign the "len" variable after defining it
  -Remove the brackets on both sides of "opt-> data.nbytes"
Changes in v4:
  -Rename variable name "opcode_addr_dummy_sum" to "len".
  -The comparison of "spi_max_message_size(mem->spi)" and "len" was removed.
  -Adjust their order when comparing the sizes of "spi_max_message_size(mem->spi)" and "len"
  -Changing the "unsigned long" type in the code to "size_t"
Changes in v3:
  -Rename variable name "val" to "opcode_addr_dummy_sum".
  -Place the legitimacy of the transfer size(i.e., "spi_max_message_size(mem->spi)" and
  -"opcode_addr_dummy_sum") into "if (! ctlr - > mem_ops | |! ctlr-> mem_ops->exec_op) {"
structure and add "spi_max_transfer_size(mem->spi) and opcode_addr_dummy_sum".
  -Adjust the formatting alignment of the code.
  -"(unsigned long)op->data.nbytes" was modified to "(unsigned long)(op->data.nbytes)".
Changes in v2:
  -Place the adjusted transfer bytes code in spi_mem_adjust_op_size() and  check
spi_max_message_size(mem->spi) value before subtracting opcode, addr and dummy bytes.
  -Change the code from fsl-espi controller to generic code(The adjustment of spi transmission
length was originally modified in the "drivers/spi/spi-fsl-espi.c" file, and now the adjustment
of transfer length is made in the "drivers/spi/spi-mem.c" file)

 drivers/spi/spi-mem.c | 16 ++++++++++++++++
 1 file changed, 16 insertions(+)

diff --git a/drivers/spi/spi-mem.c b/drivers/spi/spi-mem.c
index 990770d..6184fa1 100644
--- a/drivers/spi/spi-mem.c
+++ b/drivers/spi/spi-mem.c
@@ -328,10 +328,26 @@ EXPORT_SYMBOL_GPL(spi_mem_exec_op);
 int spi_mem_adjust_op_size(struct spi_mem *mem, struct spi_mem_op *op)
 {
 	struct spi_controller *ctlr = mem->spi->controller;
+	size_t len;
+
+	len = sizeof(op->cmd.opcode) + op->addr.nbytes + op->dummy.nbytes;
 
 	if (ctlr->mem_ops && ctlr->mem_ops->adjust_op_size)
 		return ctlr->mem_ops->adjust_op_size(mem, op);
 
+	if (!ctlr->mem_ops || !ctlr->mem_ops->exec_op) {
+		if (len > spi_max_transfer_size(mem->spi))
+			return -EINVAL;
+
+		op->data.nbytes = min3((size_t)op->data.nbytes,
+				       spi_max_transfer_size(mem->spi),
+				       spi_max_message_size(mem->spi) -
+				       len);
+
+		if (!op->data.nbytes)
+			return -EINVAL;
+	}
+
 	return 0;
 }
 EXPORT_SYMBOL_GPL(spi_mem_adjust_op_size);
-- 
2.7.4

[PATCH v5] spi: spi-mem: Adjust op len based on message/transfer size limitations

[Chuanhua Han]

We need that to adjust the len of the 2nd transfer (called data in 
spi-mem) if it's too long to fit in a SPI message or SPI transfer.

Fixes: c36ff266dc82 ("spi: Extend the core to ease integration of SPI memory controllers")
Cc: <stable@vger.kernel.org>
Signed-off-by: Chuanhua Han <chuanhua.han@nxp.com>
Suggested-by: Boris Brezillon <boris.brezillon@bootlin.com>
---
Changes in v5:
  -Add the validation check after the op->data.nbytes assignment
  -Assign the "len" variable after defining it
  -Remove the brackets on both sides of "opt-> data.nbytes"
Changes in v4:
  -Rename variable name "opcode_addr_dummy_sum" to "len".
  -The comparison of "spi_max_message_size(mem->spi)" and "len" was removed.
  -Adjust their order when comparing the sizes of "spi_max_message_size(mem->spi)" and "len"
  -Changing the "unsigned long" type in the code to "size_t"
Changes in v3:
  -Rename variable name "val" to "opcode_addr_dummy_sum".
  -Place the legitimacy of the transfer size(i.e., "spi_max_message_size(mem->spi)" and
  -"opcode_addr_dummy_sum") into "if (! ctlr - > mem_ops | |! ctlr-> mem_ops->exec_op) {"
structure and add "spi_max_transfer_size(mem->spi) and opcode_addr_dummy_sum".
  -Adjust the formatting alignment of the code.
  -"(unsigned long)op->data.nbytes" was modified to "(unsigned long)(op->data.nbytes)".
Changes in v2:
  -Place the adjusted transfer bytes code in spi_mem_adjust_op_size() and  check
spi_max_message_size(mem->spi) value before subtracting opcode, addr and dummy bytes.
  -Change the code from fsl-espi controller to generic code(The adjustment of spi transmission
length was originally modified in the "drivers/spi/spi-fsl-espi.c" file, and now the adjustment
of transfer length is made in the "drivers/spi/spi-mem.c" file)

 drivers/spi/spi-mem.c | 16 ++++++++++++++++
 1 file changed, 16 insertions(+)

diff --git a/drivers/spi/spi-mem.c b/drivers/spi/spi-mem.c
index 990770d..6184fa1 100644
--- a/drivers/spi/spi-mem.c
+++ b/drivers/spi/spi-mem.c
@@ -328,10 +328,26 @@ EXPORT_SYMBOL_GPL(spi_mem_exec_op);
 int spi_mem_adjust_op_size(struct spi_mem *mem, struct spi_mem_op *op)
 {
 	struct spi_controller *ctlr = mem->spi->controller;
+	size_t len;
+
+	len = sizeof(op->cmd.opcode) + op->addr.nbytes + op->dummy.nbytes;
 
 	if (ctlr->mem_ops && ctlr->mem_ops->adjust_op_size)
 		return ctlr->mem_ops->adjust_op_size(mem, op);
 
+	if (!ctlr->mem_ops || !ctlr->mem_ops->exec_op) {
+		if (len > spi_max_transfer_size(mem->spi))
+			return -EINVAL;
+
+		op->data.nbytes = min3((size_t)op->data.nbytes,
+				       spi_max_transfer_size(mem->spi),
+				       spi_max_message_size(mem->spi) -
+				       len);
+
+		if (!op->data.nbytes)
+			return -EINVAL;
+	}
+
 	return 0;
 }
 EXPORT_SYMBOL_GPL(spi_mem_adjust_op_size);
-- 
2.7.4

[PATCH v5] spi: spi-mem: Adjust op len based on message/transfer size limitations

[Chuanhua Han]

We need that to adjust the len of the 2nd transfer (called data in spi-mem)
if it's too long to fit in a  SPI message or SPI transfer.

Fixes: c36ff266dc82 ("spi: Extend the core to ease integration of SPI memory controllers")
Cc: <stable@vger.kernel.org>
Signed-off-by: Chuanhua Han <chuanhua.han@nxp.com>
Suggested-by: Boris Brezillon <boris.brezillon@bootlin.com>
---
Changes in v5:
  -Add the validation check after the op->data.nbytes assignment
  -Assign the "len" variable after defining it
Changes in v4:
  -Rename variable name "opcode_addr_dummy_sum" to "len".
  -The comparison of "spi_max_message_size(mem->spi)" and "len" was removed.
  -Adjust their order when comparing the sizes of "spi_max_message_size(mem->spi)" and "len"
  -Changing the "unsigned long" type in the code to "size_t"
Changes in v3:
  -Rename variable name "val" to "opcode_addr_dummy_sum".
  -Place the legitimacy of the transfer size(i.e., "spi_max_message_size(mem->spi)" and
  -"opcode_addr_dummy_sum") into "if (! ctlr - > mem_ops | |! ctlr-> mem_ops->exec_op) {"
structure and add "spi_max_transfer_size(mem->spi) and opcode_addr_dummy_sum".
  -Adjust the formatting alignment of the code.
  -"(unsigned long)op->data.nbytes" was modified to "(unsigned long)(op->data.nbytes)".
Changes in v2:
  -Place the adjusted transfer bytes code in spi_mem_adjust_op_size() and  check
spi_max_message_size(mem->spi) value before subtracting opcode, addr and dummy bytes.
  -Change the code from fsl-espi controller to generic code(The adjustment of spi transmission
length was originally modified in the "drivers/spi/spi-fsl-espi.c" file, and now the adjustment
of transfer length is made in the "drivers/spi/spi-mem.c" file)

 drivers/spi/spi-mem.c | 16 ++++++++++++++++
 1 file changed, 16 insertions(+)

diff --git a/drivers/spi/spi-mem.c b/drivers/spi/spi-mem.c
index 990770d..6184fa1 100644
--- a/drivers/spi/spi-mem.c
+++ b/drivers/spi/spi-mem.c
@@ -328,10 +328,26 @@ EXPORT_SYMBOL_GPL(spi_mem_exec_op);
 int spi_mem_adjust_op_size(struct spi_mem *mem, struct spi_mem_op *op)
 {
 	struct spi_controller *ctlr = mem->spi->controller;
+	size_t len;
+
+	len = sizeof(op->cmd.opcode) + op->addr.nbytes + op->dummy.nbytes;
 
 	if (ctlr->mem_ops && ctlr->mem_ops->adjust_op_size)
 		return ctlr->mem_ops->adjust_op_size(mem, op);
 
+	if (!ctlr->mem_ops || !ctlr->mem_ops->exec_op) {
+		if (len > spi_max_transfer_size(mem->spi))
+			return -EINVAL;
+
+		op->data.nbytes = min3((size_t)(op->data.nbytes),
+				       spi_max_transfer_size(mem->spi),
+				       spi_max_message_size(mem->spi) -
+				       len);
+
+		if (!op->data.nbytes)
+			return -EINVAL;
+	}
+
 	return 0;
 }
 EXPORT_SYMBOL_GPL(spi_mem_adjust_op_size);
-- 
2.7.4