[PATCH 00/12] i2c: quirks: add zero length checks and update drivers

[PATCH 00/12] i2c: quirks: add zero length checks and update drivers

[Wolfram Sang]

I had this idea for quite some time on my todo list but a soon to be
implemented refactoring in the i2c-rcar driver now finally made me do it. Add a
'can't do 0 length messages' quirk to the quirk infrastructure for and remove
the manual handling from the drivers. This makes the quirk much more visible.
(Quite some prominent vendors in that list) We also have a centralized place to
handle updates to the quirk detection if that is ever needed.

I have tested this with the i2c-rcar and i2c-sh_mobile driver on a Renesas
SalvatorXS board equipped with M3-N (r8a77965).

A git branch can be found here:

git://git.kernel.org/pub/scm/linux/kernel/git/wsa/linux.git i2c/quirk-no-zero-len

Looking forward to comments, reviews, tests...

Thanks,

   Wolfram

Wolfram Sang (12):
  i2c: quirks: add zero length checks
  i2c: designware-master: use core to detect 'no zero length' quirk
  i2c: mxs: use core to detect 'no zero length' quirk
  i2c: omap: use core to detect 'no zero length' quirk
  i2c: pmcmsp: use core to detect 'no zero length' quirk
  i2c: qup: use core to detect 'no zero length' quirk
  i2c: stu300: use core to detect 'no zero length' quirk
  i2c: tegra: use core to detect 'no zero length' quirk
  i2c: zx2967: use core to detect 'no zero length' quirk
  i2c: rcar: use core to detect 'no zero length' quirk
  i2c: xlr: use core to detect 'no zero length' quirk
  i2c: sh_mobile: use core to detect 'no zero length read' quirk

 drivers/i2c/busses/i2c-designware-master.c | 12 +++++-------
 drivers/i2c/busses/i2c-mxs.c               |  8 +++++---
 drivers/i2c/busses/i2c-omap.c              |  8 +++++---
 drivers/i2c/busses/i2c-pmcmsp.c            | 17 +----------------
 drivers/i2c/busses/i2c-qup.c               | 14 ++++++--------
 drivers/i2c/busses/i2c-rcar.c              | 13 ++++++-------
 drivers/i2c/busses/i2c-sh_mobile.c         | 10 +++++-----
 drivers/i2c/busses/i2c-stu300.c            | 12 ++++++------
 drivers/i2c/busses/i2c-tegra.c             |  4 +---
 drivers/i2c/busses/i2c-xlr.c               | 11 +++++------
 drivers/i2c/busses/i2c-zx2967.c            |  8 +++++---
 drivers/i2c/i2c-core-base.c                |  6 ++++++
 include/linux/i2c.h                        |  4 ++++
 13 files changed, 60 insertions(+), 67 deletions(-)

-- 
2.11.0

[PATCH 04/12] i2c: omap: use core to detect 'no zero length' quirk

[Wolfram Sang]

And don't reimplement in the driver.

Signed-off-by: Wolfram Sang <wsa+renesas@sang-engineering.com>
---

Only build tested.

 drivers/i2c/busses/i2c-omap.c | 8 +++++---
 1 file changed, 5 insertions(+), 3 deletions(-)

diff --git a/drivers/i2c/busses/i2c-omap.c b/drivers/i2c/busses/i2c-omap.c
index 65d06a819307..b1086bfb0465 100644
--- a/drivers/i2c/busses/i2c-omap.c
+++ b/drivers/i2c/busses/i2c-omap.c
@@ -661,9 +661,6 @@ static int omap_i2c_xfer_msg(struct i2c_adapter *adap,
 	dev_dbg(omap->dev, "addr: 0x%04x, len: %d, flags: 0x%x, stop: %d\n",
 		msg->addr, msg->len, msg->flags, stop);
 
-	if (msg->len == 0)
-		return -EINVAL;
-
 	omap->receiver = !!(msg->flags & I2C_M_RD);
 	omap_i2c_resize_fifo(omap, msg->len, omap->receiver);
 
@@ -1179,6 +1176,10 @@ static const struct i2c_algorithm omap_i2c_algo = {
 	.functionality	= omap_i2c_func,
 };
 
+static const struct i2c_adapter_quirks omap_i2c_quirks = {
+	.flags = I2C_AQ_NO_ZERO_LEN,
+};
+
 #ifdef CONFIG_OF
 static struct omap_i2c_bus_platform_data omap2420_pdata = {
 	.rev = OMAP_I2C_IP_VERSION_1,
@@ -1453,6 +1454,7 @@ omap_i2c_probe(struct platform_device *pdev)
 	adap->class = I2C_CLASS_DEPRECATED;
 	strlcpy(adap->name, "OMAP I2C adapter", sizeof(adap->name));
 	adap->algo = &omap_i2c_algo;
+	adap->quirks = &omap_i2c_quirks;
 	adap->dev.parent = &pdev->dev;
 	adap->dev.of_node = pdev->dev.of_node;
 	adap->bus_recovery_info = &omap_i2c_bus_recovery_info;
-- 
2.11.0

Re: [PATCH 00/12] i2c: quirks: add zero length checks and update drivers

[Andy Shevchenko]

On Mon, Jul 23, 2018 at 11:26 PM, Wolfram Sang
<wsa+renesas@sang-engineering.com> wrote:
> I had this idea for quite some time on my todo list but a soon to be
> implemented refactoring in the i2c-rcar driver now finally made me do it. Add a
> 'can't do 0 length messages' quirk to the quirk infrastructure for and remove
> the manual handling from the drivers. This makes the quirk much more visible.
> (Quite some prominent vendors in that list) We also have a centralized place to
> handle updates to the quirk detection if that is ever needed.
>
> I have tested this with the i2c-rcar and i2c-sh_mobile driver on a Renesas
> SalvatorXS board equipped with M3-N (r8a77965).
>
> A git branch can be found here:
>
> git://git.kernel.org/pub/scm/linux/kernel/git/wsa/linux.git i2c/quirk-no-zero-len
>
> Looking forward to comments, reviews, tests...

Thanks!

Reviewed-by: Andy Shevchenko <andy.shevchenko@gmail.com>

for patches 1 and 2.

>
> Thanks,
>
>    Wolfram
>
> Wolfram Sang (12):
>   i2c: quirks: add zero length checks
>   i2c: designware-master: use core to detect 'no zero length' quirk
>   i2c: mxs: use core to detect 'no zero length' quirk
>   i2c: omap: use core to detect 'no zero length' quirk
>   i2c: pmcmsp: use core to detect 'no zero length' quirk
>   i2c: qup: use core to detect 'no zero length' quirk
>   i2c: stu300: use core to detect 'no zero length' quirk
>   i2c: tegra: use core to detect 'no zero length' quirk
>   i2c: zx2967: use core to detect 'no zero length' quirk
>   i2c: rcar: use core to detect 'no zero length' quirk
>   i2c: xlr: use core to detect 'no zero length' quirk
>   i2c: sh_mobile: use core to detect 'no zero length read' quirk
>
>  drivers/i2c/busses/i2c-designware-master.c | 12 +++++-------
>  drivers/i2c/busses/i2c-mxs.c               |  8 +++++---
>  drivers/i2c/busses/i2c-omap.c              |  8 +++++---
>  drivers/i2c/busses/i2c-pmcmsp.c            | 17 +----------------
>  drivers/i2c/busses/i2c-qup.c               | 14 ++++++--------
>  drivers/i2c/busses/i2c-rcar.c              | 13 ++++++-------
>  drivers/i2c/busses/i2c-sh_mobile.c         | 10 +++++-----
>  drivers/i2c/busses/i2c-stu300.c            | 12 ++++++------
>  drivers/i2c/busses/i2c-tegra.c             |  4 +---
>  drivers/i2c/busses/i2c-xlr.c               | 11 +++++------
>  drivers/i2c/busses/i2c-zx2967.c            |  8 +++++---
>  drivers/i2c/i2c-core-base.c                |  6 ++++++
>  include/linux/i2c.h                        |  4 ++++
>  13 files changed, 60 insertions(+), 67 deletions(-)
>
> --
> 2.11.0
>



-- 
With Best Regards,
Andy Shevchenko

Re: [PATCH 00/12] i2c: quirks: add zero length checks and update drivers

[Wolfram Sang]

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On Mon, Jul 23, 2018 at 10:26:04PM +0200, Wolfram Sang wrote:
> I had this idea for quite some time on my todo list but a soon to be
> implemented refactoring in the i2c-rcar driver now finally made me do it. Add a
> 'can't do 0 length messages' quirk to the quirk infrastructure for and remove
> the manual handling from the drivers. This makes the quirk much more visible.
> (Quite some prominent vendors in that list) We also have a centralized place to
> handle updates to the quirk detection if that is ever needed.
> 
> I have tested this with the i2c-rcar and i2c-sh_mobile driver on a Renesas
> SalvatorXS board equipped with M3-N (r8a77965).
> 
> A git branch can be found here:
> 
> git://git.kernel.org/pub/scm/linux/kernel/git/wsa/linux.git i2c/quirk-no-zero-len
> 
> Looking forward to comments, reviews, tests...

I applied all the patches which either got acks from the maintainers or
have no maintainers. I'll reply individually to which I applied. I will
wait some more for other acks before I'll resend next cycle.


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Re: [PATCH 00/12] i2c: quirks: add zero length checks and update drivers

[Wolfram Sang]

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> Reviewed-by: Andy Shevchenko <andy.shevchenko@gmail.com>
> 
> for patches 1 and 2.

Thanks, Andy. If you could reply with that to the individual patches,
then patchwork picks up the tags for me making my life a little easier.


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Re: [PATCH 04/12] i2c: omap: use core to detect 'no zero length' quirk

[Wolfram Sang]

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On Mon, Jul 23, 2018 at 10:26:08PM +0200, Wolfram Sang wrote:
> And don't reimplement in the driver.
> 
> Signed-off-by: Wolfram Sang <wsa+renesas@sang-engineering.com>

Ping.


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Re: [PATCH 04/12] i2c: omap: use core to detect 'no zero length' quirk

[Grygorii Strashko]

On 10/05/2018 07:24 AM, Wolfram Sang wrote:
> On Mon, Jul 23, 2018 at 10:26:08PM +0200, Wolfram Sang wrote:
>> And don't reimplement in the driver.
>>
>> Signed-off-by: Wolfram Sang <wsa+renesas@sang-engineering.com>
> 
> Ping.
> 

Reviewed-by: Grygorii Strashko <grygorii.strashko@ti.com>

-- 
regards,
-grygorii

Re: [PATCH 04/12] i2c: omap: use core to detect 'no zero length' quirk

[Tony Lindgren]

* Grygorii Strashko <grygorii.strashko@ti.com> [181005 14:16]:
> 
> 
> On 10/05/2018 07:24 AM, Wolfram Sang wrote:
> > On Mon, Jul 23, 2018 at 10:26:08PM +0200, Wolfram Sang wrote:
> > > And don't reimplement in the driver.
> > > 
> > > Signed-off-by: Wolfram Sang <wsa+renesas@sang-engineering.com>
> > 
> > Ping.
> > 
> 
> Reviewed-by: Grygorii Strashko <grygorii.strashko@ti.com>

Acked-by: Tony Lindgren <tony@atomide.com>

Re: [PATCH 04/12] i2c: omap: use core to detect 'no zero length' quirk

[Wolfram Sang]

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On Mon, Jul 23, 2018 at 10:26:08PM +0200, Wolfram Sang wrote:
> And don't reimplement in the driver.
> 
> Signed-off-by: Wolfram Sang <wsa+renesas@sang-engineering.com>

Applied to for-next, thanks!


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