* [PATCH] spi: core: Validate lenght of the transfers in message
@ 2014-02-13 14:46 ` Ivan T. Ivanov
0 siblings, 0 replies; 11+ messages in thread
From: Ivan T. Ivanov @ 2014-02-13 14:46 UTC (permalink / raw)
To: Mark Brown; +Cc: Ivan T. Ivanov, linux-spi, linux-kernel
From: "Ivan T. Ivanov" <iivanov@mm-sol.com>
SPI transfer lenght should be a power-of-two multiple
of eight bits.
Signed-off-by: Ivan T. Ivanov <iivanov@mm-sol.com>
---
drivers/spi/spi.c | 17 +++++++++++++++++
1 file changed, 17 insertions(+)
diff --git a/drivers/spi/spi.c b/drivers/spi/spi.c
index 23756b0..474c0b0 100644
--- a/drivers/spi/spi.c
+++ b/drivers/spi/spi.c
@@ -1619,6 +1619,7 @@ static int __spi_validate(struct spi_device *spi, struct spi_message *message)
{
struct spi_master *master = spi->master;
struct spi_transfer *xfer;
+ int w_size, n_words;
if (list_empty(&message->transfers))
return -EINVAL;
@@ -1670,6 +1671,22 @@ static int __spi_validate(struct spi_device *spi, struct spi_message *message)
return -EINVAL;
}
+ /*
+ * Word size of the SPI transfer should be a power-of-two
+ * multiple of eight bits,
+ */
+ if (xfer->bits_per_word <= 8)
+ w_size = 1;
+ else if (xfer->bits_per_word <= 16)
+ w_size = 2;
+ else
+ w_size = 4;
+
+ n_words = xfer->len / w_size;
+ /* No partial transfers accepted */
+ if (!n_words || xfer->len & (w_size - 1))
+ return -EINVAL;
+
if (xfer->speed_hz && master->min_speed_hz &&
xfer->speed_hz < master->min_speed_hz)
return -EINVAL;
--
1.7.9.5
^ permalink raw reply related [flat|nested] 11+ messages in thread
* [PATCH] spi: core: Validate lenght of the transfers in message
@ 2014-02-13 14:46 ` Ivan T. Ivanov
0 siblings, 0 replies; 11+ messages in thread
From: Ivan T. Ivanov @ 2014-02-13 14:46 UTC (permalink / raw)
To: Mark Brown
Cc: Ivan T. Ivanov, linux-spi-u79uwXL29TY76Z2rM5mHXA,
linux-kernel-u79uwXL29TY76Z2rM5mHXA
From: "Ivan T. Ivanov" <iivanov-NEYub+7Iv8PQT0dZR+AlfA@public.gmane.org>
SPI transfer lenght should be a power-of-two multiple
of eight bits.
Signed-off-by: Ivan T. Ivanov <iivanov-NEYub+7Iv8PQT0dZR+AlfA@public.gmane.org>
---
drivers/spi/spi.c | 17 +++++++++++++++++
1 file changed, 17 insertions(+)
diff --git a/drivers/spi/spi.c b/drivers/spi/spi.c
index 23756b0..474c0b0 100644
--- a/drivers/spi/spi.c
+++ b/drivers/spi/spi.c
@@ -1619,6 +1619,7 @@ static int __spi_validate(struct spi_device *spi, struct spi_message *message)
{
struct spi_master *master = spi->master;
struct spi_transfer *xfer;
+ int w_size, n_words;
if (list_empty(&message->transfers))
return -EINVAL;
@@ -1670,6 +1671,22 @@ static int __spi_validate(struct spi_device *spi, struct spi_message *message)
return -EINVAL;
}
+ /*
+ * Word size of the SPI transfer should be a power-of-two
+ * multiple of eight bits,
+ */
+ if (xfer->bits_per_word <= 8)
+ w_size = 1;
+ else if (xfer->bits_per_word <= 16)
+ w_size = 2;
+ else
+ w_size = 4;
+
+ n_words = xfer->len / w_size;
+ /* No partial transfers accepted */
+ if (!n_words || xfer->len & (w_size - 1))
+ return -EINVAL;
+
if (xfer->speed_hz && master->min_speed_hz &&
xfer->speed_hz < master->min_speed_hz)
return -EINVAL;
--
1.7.9.5
--
To unsubscribe from this list: send the line "unsubscribe linux-spi" in
the body of a message to majordomo-u79uwXL29TY76Z2rM5mHXA@public.gmane.org
More majordomo info at http://vger.kernel.org/majordomo-info.html
^ permalink raw reply related [flat|nested] 11+ messages in thread
* Re: [PATCH] spi: core: Validate lenght of the transfers in message
@ 2014-02-13 21:27 ` Gerhard Sittig
0 siblings, 0 replies; 11+ messages in thread
From: Gerhard Sittig @ 2014-02-13 21:27 UTC (permalink / raw)
To: Ivan T. Ivanov; +Cc: Mark Brown, linux-spi, linux-kernel
On Thu, Feb 13, 2014 at 16:46 +0200, Ivan T. Ivanov wrote:
>
> From: "Ivan T. Ivanov" <iivanov@mm-sol.com>
>
> SPI transfer lenght should be a power-of-two multiple
> of eight bits.
Are you suggesting that an SPI transfer cannot consist of e.g.
three bytes? This would be surprising, and certainly would be
rather wrong an assumption. Am I missing/misunderstanding
something?
virtually yours
Gerhard Sittig
--
DENX Software Engineering GmbH, MD: Wolfgang Denk & Detlev Zundel
HRB 165235 Munich, Office: Kirchenstr. 5, D-82194 Groebenzell, Germany
Phone: +49-8142-66989-0 Fax: +49-8142-66989-80 Email: office@denx.de
^ permalink raw reply [flat|nested] 11+ messages in thread
* Re: [PATCH] spi: core: Validate lenght of the transfers in message
@ 2014-02-13 21:27 ` Gerhard Sittig
0 siblings, 0 replies; 11+ messages in thread
From: Gerhard Sittig @ 2014-02-13 21:27 UTC (permalink / raw)
To: Ivan T. Ivanov
Cc: Mark Brown, linux-spi-u79uwXL29TY76Z2rM5mHXA,
linux-kernel-u79uwXL29TY76Z2rM5mHXA
On Thu, Feb 13, 2014 at 16:46 +0200, Ivan T. Ivanov wrote:
>
> From: "Ivan T. Ivanov" <iivanov-NEYub+7Iv8PQT0dZR+AlfA@public.gmane.org>
>
> SPI transfer lenght should be a power-of-two multiple
> of eight bits.
Are you suggesting that an SPI transfer cannot consist of e.g.
three bytes? This would be surprising, and certainly would be
rather wrong an assumption. Am I missing/misunderstanding
something?
virtually yours
Gerhard Sittig
--
DENX Software Engineering GmbH, MD: Wolfgang Denk & Detlev Zundel
HRB 165235 Munich, Office: Kirchenstr. 5, D-82194 Groebenzell, Germany
Phone: +49-8142-66989-0 Fax: +49-8142-66989-80 Email: office-ynQEQJNshbs@public.gmane.org
--
To unsubscribe from this list: send the line "unsubscribe linux-spi" in
the body of a message to majordomo-u79uwXL29TY76Z2rM5mHXA@public.gmane.org
More majordomo info at http://vger.kernel.org/majordomo-info.html
^ permalink raw reply [flat|nested] 11+ messages in thread
* Re: [PATCH] spi: core: Validate lenght of the transfers in message
@ 2014-02-14 0:26 ` Mark Brown
0 siblings, 0 replies; 11+ messages in thread
From: Mark Brown @ 2014-02-14 0:26 UTC (permalink / raw)
To: Gerhard Sittig; +Cc: Ivan T. Ivanov, linux-spi, linux-kernel
[-- Attachment #1: Type: text/plain, Size: 628 bytes --]
On Thu, Feb 13, 2014 at 10:27:57PM +0100, Gerhard Sittig wrote:
> On Thu, Feb 13, 2014 at 16:46 +0200, Ivan T. Ivanov wrote:
> > SPI transfer lenght should be a power-of-two multiple
> > of eight bits.
> Are you suggesting that an SPI transfer cannot consist of e.g.
> three bytes? This would be surprising, and certainly would be
> rather wrong an assumption. Am I missing/misunderstanding
> something?
The check is supposed to be verifying that the transfer is a whole
number of the current SPI word size as I understand it (not actually
looked at the change yet but that's where it came from, factored out of
a driver).
[-- Attachment #2: Digital signature --]
[-- Type: application/pgp-signature, Size: 836 bytes --]
^ permalink raw reply [flat|nested] 11+ messages in thread
* Re: [PATCH] spi: core: Validate lenght of the transfers in message
@ 2014-02-14 0:26 ` Mark Brown
0 siblings, 0 replies; 11+ messages in thread
From: Mark Brown @ 2014-02-14 0:26 UTC (permalink / raw)
To: Gerhard Sittig
Cc: Ivan T. Ivanov, linux-spi-u79uwXL29TY76Z2rM5mHXA,
linux-kernel-u79uwXL29TY76Z2rM5mHXA
[-- Attachment #1: Type: text/plain, Size: 628 bytes --]
On Thu, Feb 13, 2014 at 10:27:57PM +0100, Gerhard Sittig wrote:
> On Thu, Feb 13, 2014 at 16:46 +0200, Ivan T. Ivanov wrote:
> > SPI transfer lenght should be a power-of-two multiple
> > of eight bits.
> Are you suggesting that an SPI transfer cannot consist of e.g.
> three bytes? This would be surprising, and certainly would be
> rather wrong an assumption. Am I missing/misunderstanding
> something?
The check is supposed to be verifying that the transfer is a whole
number of the current SPI word size as I understand it (not actually
looked at the change yet but that's where it came from, factored out of
a driver).
[-- Attachment #2: Digital signature --]
[-- Type: application/pgp-signature, Size: 836 bytes --]
^ permalink raw reply [flat|nested] 11+ messages in thread
* Re: [PATCH] spi: core: Validate lenght of the transfers in message
@ 2014-02-14 8:16 ` Ivan T. Ivanov
0 siblings, 0 replies; 11+ messages in thread
From: Ivan T. Ivanov @ 2014-02-14 8:16 UTC (permalink / raw)
To: Mark Brown; +Cc: Gerhard Sittig, linux-spi, linux-kernel
On Fri, 2014-02-14 at 00:26 +0000, Mark Brown wrote:
> On Thu, Feb 13, 2014 at 10:27:57PM +0100, Gerhard Sittig wrote:
> > On Thu, Feb 13, 2014 at 16:46 +0200, Ivan T. Ivanov wrote:
>
> > > SPI transfer lenght should be a power-of-two multiple
> > > of eight bits.
>
> > Are you suggesting that an SPI transfer cannot consist of e.g.
> > three bytes? This would be surprising, and certainly would be
> > rather wrong an assumption. Am I missing/misunderstanding
> > something?
>
> The check is supposed to be verifying that the transfer is a whole
> number of the current SPI word size as I understand it (not actually
> looked at the change yet but that's where it came from, factored out of
> a driver).
Yes. Comment is not correct. Is this better?
"SPI transfer length should be multiple of SPI word size, where SPI
word size should be power-of-two multiple"
Regards,
Ivan
^ permalink raw reply [flat|nested] 11+ messages in thread
* Re: [PATCH] spi: core: Validate lenght of the transfers in message
@ 2014-02-14 8:16 ` Ivan T. Ivanov
0 siblings, 0 replies; 11+ messages in thread
From: Ivan T. Ivanov @ 2014-02-14 8:16 UTC (permalink / raw)
To: Mark Brown
Cc: Gerhard Sittig, linux-spi-u79uwXL29TY76Z2rM5mHXA,
linux-kernel-u79uwXL29TY76Z2rM5mHXA
On Fri, 2014-02-14 at 00:26 +0000, Mark Brown wrote:
> On Thu, Feb 13, 2014 at 10:27:57PM +0100, Gerhard Sittig wrote:
> > On Thu, Feb 13, 2014 at 16:46 +0200, Ivan T. Ivanov wrote:
>
> > > SPI transfer lenght should be a power-of-two multiple
> > > of eight bits.
>
> > Are you suggesting that an SPI transfer cannot consist of e.g.
> > three bytes? This would be surprising, and certainly would be
> > rather wrong an assumption. Am I missing/misunderstanding
> > something?
>
> The check is supposed to be verifying that the transfer is a whole
> number of the current SPI word size as I understand it (not actually
> looked at the change yet but that's where it came from, factored out of
> a driver).
Yes. Comment is not correct. Is this better?
"SPI transfer length should be multiple of SPI word size, where SPI
word size should be power-of-two multiple"
Regards,
Ivan
--
To unsubscribe from this list: send the line "unsubscribe linux-spi" in
the body of a message to majordomo-u79uwXL29TY76Z2rM5mHXA@public.gmane.org
More majordomo info at http://vger.kernel.org/majordomo-info.html
^ permalink raw reply [flat|nested] 11+ messages in thread
* Re: [PATCH] spi: core: Validate lenght of the transfers in message
2014-02-14 8:16 ` Ivan T. Ivanov
@ 2014-02-14 15:05 ` Mark Brown
-1 siblings, 0 replies; 11+ messages in thread
From: Mark Brown @ 2014-02-14 15:05 UTC (permalink / raw)
To: Ivan T. Ivanov; +Cc: Gerhard Sittig, linux-spi, linux-kernel
[-- Attachment #1: Type: text/plain, Size: 362 bytes --]
On Fri, Feb 14, 2014 at 10:16:05AM +0200, Ivan T. Ivanov wrote:
> "SPI transfer length should be multiple of SPI word size, where SPI
> word size should be power-of-two multiple"
Yes, that's clearer though you could in theory have a three byte word
(I'm not sure that anyone would actually do that but it's possible). I
do have a comment on the code as well.
[-- Attachment #2: Digital signature --]
[-- Type: application/pgp-signature, Size: 836 bytes --]
^ permalink raw reply [flat|nested] 11+ messages in thread
* Re: [PATCH] spi: core: Validate lenght of the transfers in message
@ 2014-02-14 15:05 ` Mark Brown
0 siblings, 0 replies; 11+ messages in thread
From: Mark Brown @ 2014-02-14 15:05 UTC (permalink / raw)
To: Ivan T. Ivanov
Cc: Gerhard Sittig, linux-spi-u79uwXL29TY76Z2rM5mHXA,
linux-kernel-u79uwXL29TY76Z2rM5mHXA
[-- Attachment #1: Type: text/plain, Size: 362 bytes --]
On Fri, Feb 14, 2014 at 10:16:05AM +0200, Ivan T. Ivanov wrote:
> "SPI transfer length should be multiple of SPI word size, where SPI
> word size should be power-of-two multiple"
Yes, that's clearer though you could in theory have a three byte word
(I'm not sure that anyone would actually do that but it's possible). I
do have a comment on the code as well.
[-- Attachment #2: Digital signature --]
[-- Type: application/pgp-signature, Size: 836 bytes --]
^ permalink raw reply [flat|nested] 11+ messages in thread
* Re: [PATCH] spi: core: Validate lenght of the transfers in message
2014-02-13 14:46 ` Ivan T. Ivanov
(?)
(?)
@ 2014-02-14 15:06 ` Mark Brown
-1 siblings, 0 replies; 11+ messages in thread
From: Mark Brown @ 2014-02-14 15:06 UTC (permalink / raw)
To: Ivan T. Ivanov; +Cc: linux-spi, linux-kernel
[-- Attachment #1: Type: text/plain, Size: 364 bytes --]
On Thu, Feb 13, 2014 at 04:46:46PM +0200, Ivan T. Ivanov wrote:
> + /* No partial transfers accepted */
> + if (!n_words || xfer->len & (w_size - 1))
> + return -EINVAL;
Please write this using % rather than the & - it's a lot clearer what
it's checking for, I had to think what the above meant. Hopefully the
compiler will make it equally fast either way.
[-- Attachment #2: Digital signature --]
[-- Type: application/pgp-signature, Size: 836 bytes --]
^ permalink raw reply [flat|nested] 11+ messages in thread
end of thread, other threads:[~2014-02-14 18:26 UTC | newest]
Thread overview: 11+ messages (download: mbox.gz / follow: Atom feed)
-- links below jump to the message on this page --
2014-02-13 14:46 [PATCH] spi: core: Validate lenght of the transfers in message Ivan T. Ivanov
2014-02-13 14:46 ` Ivan T. Ivanov
2014-02-13 21:27 ` Gerhard Sittig
2014-02-13 21:27 ` Gerhard Sittig
2014-02-14 0:26 ` Mark Brown
2014-02-14 0:26 ` Mark Brown
2014-02-14 8:16 ` Ivan T. Ivanov
2014-02-14 8:16 ` Ivan T. Ivanov
2014-02-14 15:05 ` Mark Brown
2014-02-14 15:05 ` Mark Brown
2014-02-14 15:06 ` Mark Brown
This is an external index of several public inboxes,
see mirroring instructions on how to clone and mirror
all data and code used by this external index.