<feed xmlns='http://www.w3.org/2005/Atom'>
<title>linux-toradex.git/drivers/i2c, branch v5.7-rc2</title>
<subtitle>Linux kernel for Apalis and Colibri modules</subtitle>
<link rel='alternate' type='text/html' href='https://git.toradex.cn/cgit/linux-toradex.git/'/>
<entry>
<title>i2c: tegra: Synchronize DMA before termination</title>
<updated>2020-04-15T16:27:31+00:00</updated>
<author>
<name>Dmitry Osipenko</name>
<email>digetx@gmail.com</email>
</author>
<published>2020-03-24T19:12:17+00:00</published>
<link rel='alternate' type='text/html' href='https://git.toradex.cn/cgit/linux-toradex.git/commit/?id=8814044fe0fa182abc9ff818d3da562de98bc9a7'/>
<id>8814044fe0fa182abc9ff818d3da562de98bc9a7</id>
<content type='text'>
DMA transfer could be completed, but CPU (which handles DMA interrupt)
may get too busy and can't handle the interrupt in a timely manner,
despite of DMA IRQ being raised. In this case the DMA state needs to
synchronized before terminating DMA transfer in order not to miss the
DMA transfer completion.

Signed-off-by: Dmitry Osipenko &lt;digetx@gmail.com&gt;
Signed-off-by: Wolfram Sang &lt;wsa@the-dreams.de&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
DMA transfer could be completed, but CPU (which handles DMA interrupt)
may get too busy and can't handle the interrupt in a timely manner,
despite of DMA IRQ being raised. In this case the DMA state needs to
synchronized before terminating DMA transfer in order not to miss the
DMA transfer completion.

Signed-off-by: Dmitry Osipenko &lt;digetx@gmail.com&gt;
Signed-off-by: Wolfram Sang &lt;wsa@the-dreams.de&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>i2c: tegra: Better handle case where CPU0 is busy for a long time</title>
<updated>2020-04-15T16:27:25+00:00</updated>
<author>
<name>Dmitry Osipenko</name>
<email>digetx@gmail.com</email>
</author>
<published>2020-03-24T19:12:16+00:00</published>
<link rel='alternate' type='text/html' href='https://git.toradex.cn/cgit/linux-toradex.git/commit/?id=a900aeac253729411cf33c6cb598c152e9e4137f'/>
<id>a900aeac253729411cf33c6cb598c152e9e4137f</id>
<content type='text'>
Boot CPU0 always handle I2C interrupt and under some rare circumstances
(like running KASAN + NFS root) it may stuck in uninterruptible state for
a significant time. In this case we will get timeout if I2C transfer is
running on a sibling CPU, despite of IRQ being raised. In order to handle
this rare condition, the IRQ status needs to be checked after completion
timeout.

Signed-off-by: Dmitry Osipenko &lt;digetx@gmail.com&gt;
Signed-off-by: Wolfram Sang &lt;wsa@the-dreams.de&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
Boot CPU0 always handle I2C interrupt and under some rare circumstances
(like running KASAN + NFS root) it may stuck in uninterruptible state for
a significant time. In this case we will get timeout if I2C transfer is
running on a sibling CPU, despite of IRQ being raised. In order to handle
this rare condition, the IRQ status needs to be checked after completion
timeout.

Signed-off-by: Dmitry Osipenko &lt;digetx@gmail.com&gt;
Signed-off-by: Wolfram Sang &lt;wsa@the-dreams.de&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>i2c: remove i2c_new_probed_device API</title>
<updated>2020-04-15T09:48:21+00:00</updated>
<author>
<name>Wolfram Sang</name>
<email>wsa+renesas@sang-engineering.com</email>
</author>
<published>2020-04-06T12:25:31+00:00</published>
<link rel='alternate' type='text/html' href='https://git.toradex.cn/cgit/linux-toradex.git/commit/?id=3c1d1613be80c2e17f1ddf672df1d8a8caebfd0d'/>
<id>3c1d1613be80c2e17f1ddf672df1d8a8caebfd0d</id>
<content type='text'>
All in-tree users have been converted to the new i2c_new_scanned_device
function, so remove this deprecated one.

Signed-off-by: Wolfram Sang &lt;wsa+renesas@sang-engineering.com&gt;
Signed-off-by: Wolfram Sang &lt;wsa@the-dreams.de&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
All in-tree users have been converted to the new i2c_new_scanned_device
function, so remove this deprecated one.

Signed-off-by: Wolfram Sang &lt;wsa+renesas@sang-engineering.com&gt;
Signed-off-by: Wolfram Sang &lt;wsa@the-dreams.de&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>i2c: altera: use proper variable to hold errno</title>
<updated>2020-04-15T09:48:21+00:00</updated>
<author>
<name>Wolfram Sang</name>
<email>wsa+renesas@sang-engineering.com</email>
</author>
<published>2020-03-27T22:28:26+00:00</published>
<link rel='alternate' type='text/html' href='https://git.toradex.cn/cgit/linux-toradex.git/commit/?id=edb2c9dd3948738ef030c32b948543e84f4d3f81'/>
<id>edb2c9dd3948738ef030c32b948543e84f4d3f81</id>
<content type='text'>
device_property_read_u32() returns errno or 0, so we should use the
integer variable 'ret' and not the u32 'val' to hold the retval.

Fixes: 0560ad576268 ("i2c: altera: Add Altera I2C Controller driver")
Signed-off-by: Wolfram Sang &lt;wsa+renesas@sang-engineering.com&gt;
Reviewed-by: Thor Thayer &lt;thor.thayer@linux.intel.com&gt;
Signed-off-by: Wolfram Sang &lt;wsa@the-dreams.de&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
device_property_read_u32() returns errno or 0, so we should use the
integer variable 'ret' and not the u32 'val' to hold the retval.

Fixes: 0560ad576268 ("i2c: altera: Add Altera I2C Controller driver")
Signed-off-by: Wolfram Sang &lt;wsa+renesas@sang-engineering.com&gt;
Reviewed-by: Thor Thayer &lt;thor.thayer@linux.intel.com&gt;
Signed-off-by: Wolfram Sang &lt;wsa@the-dreams.de&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>i2c: designware: platdrv: Remove DPM_FLAG_SMART_SUSPEND flag on BYT and CHT</title>
<updated>2020-04-15T09:48:20+00:00</updated>
<author>
<name>Hans de Goede</name>
<email>hdegoede@redhat.com</email>
</author>
<published>2020-04-07T18:11:16+00:00</published>
<link rel='alternate' type='text/html' href='https://git.toradex.cn/cgit/linux-toradex.git/commit/?id=d79294d0de12ddd1420110813626d691f440b86f'/>
<id>d79294d0de12ddd1420110813626d691f440b86f</id>
<content type='text'>
We already set DPM_FLAG_SMART_PREPARE, so we completely skip all
callbacks (other then prepare) where possible, quoting from
dw_i2c_plat_prepare():

        /*
         * If the ACPI companion device object is present for this device, it
         * may be accessed during suspend and resume of other devices via I2C
         * operation regions, so tell the PM core and middle layers to avoid
         * skipping system suspend/resume callbacks for it in that case.
         */
        return !has_acpi_companion(dev);

Also setting the DPM_FLAG_SMART_SUSPEND will cause acpi_subsys_suspend()
to leave the controller runtime-suspended even if dw_i2c_plat_prepare()
returned 0.

Leaving the controller runtime-suspended normally, when the I2C controller
is suspended during the suspend_late phase, is not an issue because
the pm_runtime_get_sync() done by i2c_dw_xfer() will (runtime-)resume it.

But for dw I2C controllers on Bay- and Cherry-Trail devices acpi_lpss.c
leaves the controller alive until the suspend_noirq phase, because it may
be used by the _PS3 ACPI methods of PCI devices and PCI devices are left
powered on until the suspend_noirq phase.

Between the suspend_late and resume_early phases runtime-pm is disabled.
So for any ACPI I2C OPRegion accesses done after the suspend_late phase,
the pm_runtime_get_sync() done by i2c_dw_xfer() is a no-op and the
controller is left runtime-suspended.

i2c_dw_xfer() has a check to catch this condition (rather then waiting
for the I2C transfer to timeout because the controller is suspended).
acpi_subsys_suspend() leaving the controller runtime-suspended in
combination with an ACPI I2C OPRegion access done after the suspend_late
phase triggers this check, leading to the following error being logged
on a Bay Trail based Lenovo Thinkpad 8 tablet:

[   93.275882] i2c_designware 80860F41:00: Transfer while suspended
[   93.275993] WARNING: CPU: 0 PID: 412 at drivers/i2c/busses/i2c-designware-master.c:429 i2c_dw_xfer+0x239/0x280
...
[   93.276252] Workqueue: kacpi_notify acpi_os_execute_deferred
[   93.276267] RIP: 0010:i2c_dw_xfer+0x239/0x280
...
[   93.276340] Call Trace:
[   93.276366]  __i2c_transfer+0x121/0x520
[   93.276379]  i2c_transfer+0x4c/0x100
[   93.276392]  i2c_acpi_space_handler+0x219/0x510
[   93.276408]  ? up+0x40/0x60
[   93.276419]  ? i2c_acpi_notify+0x130/0x130
[   93.276433]  acpi_ev_address_space_dispatch+0x1e1/0x252
...

So since on BYT and CHT platforms we want ACPI I2c OPRegion accesses
to work until the suspend_noirq phase, we need the controller to be
runtime-resumed during the suspend phase if it is runtime-suspended
suspended at that time. This means that we must not set the
DPM_FLAG_SMART_SUSPEND on these platforms.

On BYT and CHT we already have a special ACCESS_NO_IRQ_SUSPEND flag
to make sure the controller stays functional until the suspend_noirq
phase. This commit makes the driver not set the DPM_FLAG_SMART_SUSPEND
flag when that flag is set.

Cc: stable@vger.kernel.org
Fixes: b30f2f65568f ("i2c: designware: Set IRQF_NO_SUSPEND flag for all BYT and CHT controllers")
Signed-off-by: Hans de Goede &lt;hdegoede@redhat.com&gt;
Reviewed-by: Andy Shevchenko &lt;andriy.shevchenko@linux.intel.com&gt;
Acked-by: Rafael J. Wysocki &lt;rafael.j.wysocki@intel.com&gt;
Acked-by: Jarkko Nikula &lt;jarkko.nikula@linux.intel.com&gt;
Signed-off-by: Wolfram Sang &lt;wsa@the-dreams.de&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
We already set DPM_FLAG_SMART_PREPARE, so we completely skip all
callbacks (other then prepare) where possible, quoting from
dw_i2c_plat_prepare():

        /*
         * If the ACPI companion device object is present for this device, it
         * may be accessed during suspend and resume of other devices via I2C
         * operation regions, so tell the PM core and middle layers to avoid
         * skipping system suspend/resume callbacks for it in that case.
         */
        return !has_acpi_companion(dev);

Also setting the DPM_FLAG_SMART_SUSPEND will cause acpi_subsys_suspend()
to leave the controller runtime-suspended even if dw_i2c_plat_prepare()
returned 0.

Leaving the controller runtime-suspended normally, when the I2C controller
is suspended during the suspend_late phase, is not an issue because
the pm_runtime_get_sync() done by i2c_dw_xfer() will (runtime-)resume it.

But for dw I2C controllers on Bay- and Cherry-Trail devices acpi_lpss.c
leaves the controller alive until the suspend_noirq phase, because it may
be used by the _PS3 ACPI methods of PCI devices and PCI devices are left
powered on until the suspend_noirq phase.

Between the suspend_late and resume_early phases runtime-pm is disabled.
So for any ACPI I2C OPRegion accesses done after the suspend_late phase,
the pm_runtime_get_sync() done by i2c_dw_xfer() is a no-op and the
controller is left runtime-suspended.

i2c_dw_xfer() has a check to catch this condition (rather then waiting
for the I2C transfer to timeout because the controller is suspended).
acpi_subsys_suspend() leaving the controller runtime-suspended in
combination with an ACPI I2C OPRegion access done after the suspend_late
phase triggers this check, leading to the following error being logged
on a Bay Trail based Lenovo Thinkpad 8 tablet:

[   93.275882] i2c_designware 80860F41:00: Transfer while suspended
[   93.275993] WARNING: CPU: 0 PID: 412 at drivers/i2c/busses/i2c-designware-master.c:429 i2c_dw_xfer+0x239/0x280
...
[   93.276252] Workqueue: kacpi_notify acpi_os_execute_deferred
[   93.276267] RIP: 0010:i2c_dw_xfer+0x239/0x280
...
[   93.276340] Call Trace:
[   93.276366]  __i2c_transfer+0x121/0x520
[   93.276379]  i2c_transfer+0x4c/0x100
[   93.276392]  i2c_acpi_space_handler+0x219/0x510
[   93.276408]  ? up+0x40/0x60
[   93.276419]  ? i2c_acpi_notify+0x130/0x130
[   93.276433]  acpi_ev_address_space_dispatch+0x1e1/0x252
...

So since on BYT and CHT platforms we want ACPI I2c OPRegion accesses
to work until the suspend_noirq phase, we need the controller to be
runtime-resumed during the suspend phase if it is runtime-suspended
suspended at that time. This means that we must not set the
DPM_FLAG_SMART_SUSPEND on these platforms.

On BYT and CHT we already have a special ACCESS_NO_IRQ_SUSPEND flag
to make sure the controller stays functional until the suspend_noirq
phase. This commit makes the driver not set the DPM_FLAG_SMART_SUSPEND
flag when that flag is set.

Cc: stable@vger.kernel.org
Fixes: b30f2f65568f ("i2c: designware: Set IRQF_NO_SUSPEND flag for all BYT and CHT controllers")
Signed-off-by: Hans de Goede &lt;hdegoede@redhat.com&gt;
Reviewed-by: Andy Shevchenko &lt;andriy.shevchenko@linux.intel.com&gt;
Acked-by: Rafael J. Wysocki &lt;rafael.j.wysocki@intel.com&gt;
Acked-by: Jarkko Nikula &lt;jarkko.nikula@linux.intel.com&gt;
Signed-off-by: Wolfram Sang &lt;wsa@the-dreams.de&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>Merge branch 'i2c/for-5.7' of git://git.kernel.org/pub/scm/linux/kernel/git/wsa/linux</title>
<updated>2020-04-02T22:54:13+00:00</updated>
<author>
<name>Linus Torvalds</name>
<email>torvalds@linux-foundation.org</email>
</author>
<published>2020-04-02T22:54:13+00:00</published>
<link rel='alternate' type='text/html' href='https://git.toradex.cn/cgit/linux-toradex.git/commit/?id=5c8db3eb381745c010ba746373a279e92502bdc8'/>
<id>5c8db3eb381745c010ba746373a279e92502bdc8</id>
<content type='text'>
Pull i2c updates from Wolfram Sang:
 "I2C has:

   - using defines for bus speeds to avoid mistakes in hardcoded values;
     lots of small driver updates because of that. Thanks, Andy!

   - API change: i2c_setup_smbus_alert() was renamed to
     i2c_new_smbus_alert_device() and returns ERRPTR now. All in-tree
     users have been converted

   - in the core, a rare race condition when deleting the cdev has been
     fixed. Thanks, Kevin!

   - lots of driver updates. Thanks, everyone!

  I also want to mention: The amount of review and testing tags given
  was quite high this time. Thank you to these people, too. I hope we
  can keep it like this!"

* 'i2c/for-5.7' of git://git.kernel.org/pub/scm/linux/kernel/git/wsa/linux: (34 commits)
  i2c: rcar: clean up after refactoring i2c_timings
  macintosh: convert to i2c_new_scanned_device
  i2c: drivers: Use generic definitions for bus frequencies
  i2c: algo: Use generic definitions for bus frequencies
  i2c: stm32f7: switch to I²C generic property parsing
  i2c: rcar: Consolidate timings calls in rcar_i2c_clock_calculate()
  i2c: core: Allow override timing properties with 0
  i2c: core: Provide generic definitions for bus frequencies
  i2c: mxs: Use dma_request_chan() instead dma_request_slave_channel()
  i2c: imx: remove duplicate print after platform_get_irq()
  i2c: designware: Fix spelling typos in the comments
  i2c: designware: Discard i2c_dw_read_comp_param() function
  i2c: designware: Detect the FIFO size in the common code
  i2c: dev: Fix the race between the release of i2c_dev and cdev
  i2c: qcom-geni: Drop of_platform.h include
  i2c: qcom-geni: Grow a dev pointer to simplify code
  i2c: qcom-geni: Let firmware specify irq trigger flags
  i2c: stm32f7: do not backup read-only PECR register
  i2c: smbus: remove outdated references to irq level triggers
  i2c: convert SMBus alert setup function to return an ERRPTR
  ...
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
Pull i2c updates from Wolfram Sang:
 "I2C has:

   - using defines for bus speeds to avoid mistakes in hardcoded values;
     lots of small driver updates because of that. Thanks, Andy!

   - API change: i2c_setup_smbus_alert() was renamed to
     i2c_new_smbus_alert_device() and returns ERRPTR now. All in-tree
     users have been converted

   - in the core, a rare race condition when deleting the cdev has been
     fixed. Thanks, Kevin!

   - lots of driver updates. Thanks, everyone!

  I also want to mention: The amount of review and testing tags given
  was quite high this time. Thank you to these people, too. I hope we
  can keep it like this!"

* 'i2c/for-5.7' of git://git.kernel.org/pub/scm/linux/kernel/git/wsa/linux: (34 commits)
  i2c: rcar: clean up after refactoring i2c_timings
  macintosh: convert to i2c_new_scanned_device
  i2c: drivers: Use generic definitions for bus frequencies
  i2c: algo: Use generic definitions for bus frequencies
  i2c: stm32f7: switch to I²C generic property parsing
  i2c: rcar: Consolidate timings calls in rcar_i2c_clock_calculate()
  i2c: core: Allow override timing properties with 0
  i2c: core: Provide generic definitions for bus frequencies
  i2c: mxs: Use dma_request_chan() instead dma_request_slave_channel()
  i2c: imx: remove duplicate print after platform_get_irq()
  i2c: designware: Fix spelling typos in the comments
  i2c: designware: Discard i2c_dw_read_comp_param() function
  i2c: designware: Detect the FIFO size in the common code
  i2c: dev: Fix the race between the release of i2c_dev and cdev
  i2c: qcom-geni: Drop of_platform.h include
  i2c: qcom-geni: Grow a dev pointer to simplify code
  i2c: qcom-geni: Let firmware specify irq trigger flags
  i2c: stm32f7: do not backup read-only PECR register
  i2c: smbus: remove outdated references to irq level triggers
  i2c: convert SMBus alert setup function to return an ERRPTR
  ...
</pre>
</div>
</content>
</entry>
<entry>
<title>i2c: rcar: clean up after refactoring i2c_timings</title>
<updated>2020-03-31T15:34:29+00:00</updated>
<author>
<name>Wolfram Sang</name>
<email>wsa+renesas@sang-engineering.com</email>
</author>
<published>2020-03-26T10:07:21+00:00</published>
<link rel='alternate' type='text/html' href='https://git.toradex.cn/cgit/linux-toradex.git/commit/?id=df576beee53ac97fe0a413430e623e658805891d'/>
<id>df576beee53ac97fe0a413430e623e658805891d</id>
<content type='text'>
The pointer is not really needed anymore since we have the timings
struct available in the function itself now. Remove the pointer and
access the struct directly.

Signed-off-by: Wolfram Sang &lt;wsa+renesas@sang-engineering.com&gt;
Reviewed-by: Geert Uytterhoeven &lt;geert+renesas@glider.be&gt;
Signed-off-by: Wolfram Sang &lt;wsa@the-dreams.de&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
The pointer is not really needed anymore since we have the timings
struct available in the function itself now. Remove the pointer and
access the struct directly.

Signed-off-by: Wolfram Sang &lt;wsa+renesas@sang-engineering.com&gt;
Reviewed-by: Geert Uytterhoeven &lt;geert+renesas@glider.be&gt;
Signed-off-by: Wolfram Sang &lt;wsa@the-dreams.de&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>i2c: pca-platform: Use platform_irq_get_optional</title>
<updated>2020-03-28T04:03:17+00:00</updated>
<author>
<name>Chris Packham</name>
<email>chris.packham@alliedtelesis.co.nz</email>
</author>
<published>2020-03-26T22:44:22+00:00</published>
<link rel='alternate' type='text/html' href='https://git.toradex.cn/cgit/linux-toradex.git/commit/?id=14c1fe699cad9cb0acda4559c584f136d18fea50'/>
<id>14c1fe699cad9cb0acda4559c584f136d18fea50</id>
<content type='text'>
The interrupt is not required so use platform_irq_get_optional() to
avoid error messages like

  i2c-pca-platform 22080000.i2c: IRQ index 0 not found

Signed-off-by: Chris Packham &lt;chris.packham@alliedtelesis.co.nz&gt;
Signed-off-by: Wolfram Sang &lt;wsa@the-dreams.de&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
The interrupt is not required so use platform_irq_get_optional() to
avoid error messages like

  i2c-pca-platform 22080000.i2c: IRQ index 0 not found

Signed-off-by: Chris Packham &lt;chris.packham@alliedtelesis.co.nz&gt;
Signed-off-by: Wolfram Sang &lt;wsa@the-dreams.de&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>i2c: st: fix missing struct parameter description</title>
<updated>2020-03-28T04:00:36+00:00</updated>
<author>
<name>Alain Volmat</name>
<email>avolmat@me.com</email>
</author>
<published>2020-03-26T21:22:43+00:00</published>
<link rel='alternate' type='text/html' href='https://git.toradex.cn/cgit/linux-toradex.git/commit/?id=f491c6687332920e296d0209e366fe2ca7eab1c6'/>
<id>f491c6687332920e296d0209e366fe2ca7eab1c6</id>
<content type='text'>
Fix a missing struct parameter description to allow
warning free W=1 compilation.

Signed-off-by: Alain Volmat &lt;avolmat@me.com&gt;
Reviewed-by: Patrice Chotard &lt;patrice.chotard@st.com&gt;
Signed-off-by: Wolfram Sang &lt;wsa@the-dreams.de&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
Fix a missing struct parameter description to allow
warning free W=1 compilation.

Signed-off-by: Alain Volmat &lt;avolmat@me.com&gt;
Reviewed-by: Patrice Chotard &lt;patrice.chotard@st.com&gt;
Signed-off-by: Wolfram Sang &lt;wsa@the-dreams.de&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>Merge tag 'v5.6-rc7' into i2c/for-5.7</title>
<updated>2020-03-26T11:09:58+00:00</updated>
<author>
<name>Wolfram Sang</name>
<email>wsa@the-dreams.de</email>
</author>
<published>2020-03-26T11:09:58+00:00</published>
<link rel='alternate' type='text/html' href='https://git.toradex.cn/cgit/linux-toradex.git/commit/?id=6d7e0a34206d4a5d0c619c0608eae57f4c557064'/>
<id>6d7e0a34206d4a5d0c619c0608eae57f4c557064</id>
<content type='text'>
Linux 5.6-rc7
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
Linux 5.6-rc7
</pre>
</div>
</content>
</entry>
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