Hi Tony, I had the OMAP5 running very very hot by a kernel hang (most likely a spinlock). And I wondered if there is no safety mechanism (watchdog timer).
I did a little research and there seems to be no WDT driver for the Palmas in mainline.
There was something:
https://lore.kernel.org/patchwork/patch/367777/
but it seems it did not arrive upstream. Any reasons or problems with the driver? Or a newer version sitting in some git?
BR and thanks, Nikolaus
* H. Nikolaus Schaller hns@goldelico.com [181208 21:35]:
Hi Tony, I had the OMAP5 running very very hot by a kernel hang (most likely a spinlock). And I wondered if there is no safety mechanism (watchdog timer).
I did a little research and there seems to be no WDT driver for the Palmas in mainline.
There was something:
https://lore.kernel.org/patchwork/patch/367777/
but it seems it did not arrive upstream. Any reasons or problems with the driver? Or a newer version sitting in some git?
Sorry no idea. Maybe check if it's similar to the drivers/watchdog/twl4030_wdt.c?
Note that some devices just use drivers/watchdog/omap_wdt.c that is wired to the PMIC used. So maybe the Palmas WDT was just forgotten if it was not needed?
Regards,
Tony
Hi Tony,
Am 13.12.2018 um 19:14 schrieb Tony Lindgren tony@atomide.com:
- H. Nikolaus Schaller hns@goldelico.com [181208 21:35]:
Hi Tony, I had the OMAP5 running very very hot by a kernel hang (most likely a spinlock). And I wondered if there is no safety mechanism (watchdog timer).
I did a little research and there seems to be no WDT driver for the Palmas in mainline.
There was something:
https://lore.kernel.org/patchwork/patch/367777/
but it seems it did not arrive upstream. Any reasons or problems with the driver? Or a newer version sitting in some git?
Sorry no idea. Maybe check if it's similar to the drivers/watchdog/twl4030_wdt.c?
Yes, it is. Code structure is almost the same, because it is based on twl4030 code :)
Differences: * uses enable/disable instead of start/stop (probably older WDT core API and easy to fix) * different compatible list (obviously necessary) * uses palmas_write() from include/linux/mfd/palmas.h instead of twl_i2c_write_u8() from include/linux/mfd/twl.h * (have not checked): probably different register offsets * has no remove/suspend/resume handlers (probably older WDT core API and easy to copy&paste)
But there seems to be a bug in palmas_wdt_write(). IMHO it ignores the "data" argument when passing down to palmas_write()...
So it may be that the driver did not work as proposed.
I am not sure but I think I had spotted a v10 of the patch set.
Ah, yes:
https://lore.kernel.org/patchwork/patch/367819/
There are already several review comments (including confirmation of the data argument issue) but I could not find a v11 or v12.
Note that some devices just use drivers/watchdog/omap_wdt.c that is wired to the PMIC used. So maybe the Palmas WDT was just forgotten if it was not needed?
Maybe it was simply forgotten to be completed and resubmitted.
I am not sure if Graeme is still actively working on this topic. So I put him on CC.
BR and thanks, Nikolaus
Am 15.12.2018 um 08:50 schrieb H. Nikolaus Schaller hns@goldelico.com:
Hi Tony,
Am 13.12.2018 um 19:14 schrieb Tony Lindgren tony@atomide.com:
- H. Nikolaus Schaller hns@goldelico.com [181208 21:35]:
Hi Tony, I had the OMAP5 running very very hot by a kernel hang (most likely a spinlock). And I wondered if there is no safety mechanism (watchdog timer).
I did a little research and there seems to be no WDT driver for the Palmas in mainline.
There was something:
https://lore.kernel.org/patchwork/patch/367777/
but it seems it did not arrive upstream. Any reasons or problems with the driver? Or a newer version sitting in some git?
Sorry no idea. Maybe check if it's similar to the drivers/watchdog/twl4030_wdt.c?
Yes, it is. Code structure is almost the same, because it is based on twl4030 code :)
Differences:
- uses enable/disable instead of start/stop (probably older WDT core API and easy to fix)
- different compatible list (obviously necessary)
- uses palmas_write() from include/linux/mfd/palmas.h instead of twl_i2c_write_u8() from include/linux/mfd/twl.h
- (have not checked): probably different register offsets
- has no remove/suspend/resume handlers (probably older WDT core API and easy to copy&paste)
But there seems to be a bug in palmas_wdt_write(). IMHO it ignores the "data" argument when passing down to palmas_write()...
So it may be that the driver did not work as proposed.
I am not sure but I think I had spotted a v10 of the patch set.
Ah, yes:
https://lore.kernel.org/patchwork/patch/367819/
There are already several review comments (including confirmation of the data argument issue) but I could not find a v11 or v12.
Note that some devices just use drivers/watchdog/omap_wdt.c
I have looked into that as well and to me it appears to support OMAP3 only.
that is wired to the PMIC used. So maybe the Palmas WDT was just forgotten if it was not needed?
Maybe it was simply forgotten to be completed and resubmitted.
I am not sure if Graeme is still actively working on this topic. So I put him on CC.
BR and thanks, Nikolaus
Kernel mailing list Kernel@pyra-handheld.com http://pyra-handheld.com/cgi-bin/mailman/listinfo/kernel
On Sat, 15 Dec 2018, at 7:50 AM, H. Nikolaus Schaller wrote:
Hi Tony,
Am 13.12.2018 um 19:14 schrieb Tony Lindgren tony@atomide.com:
- H. Nikolaus Schaller hns@goldelico.com [181208 21:35]:
Hi Tony, I had the OMAP5 running very very hot by a kernel hang (most likely a spinlock). And I wondered if there is no safety mechanism (watchdog timer).
I did a little research and there seems to be no WDT driver for the Palmas in mainline.
There was something:
https://lore.kernel.org/patchwork/patch/367777/
but it seems it did not arrive upstream. Any reasons or problems with the driver? Or a newer version sitting in some git?
Sorry no idea. Maybe check if it's similar to the drivers/watchdog/twl4030_wdt.c?
Yes, it is. Code structure is almost the same, because it is based on twl4030 code :)
Differences:
- uses enable/disable instead of start/stop (probably older WDT core API
and easy to fix)
- different compatible list (obviously necessary)
- uses palmas_write() from include/linux/mfd/palmas.h instead of
twl_i2c_write_u8() from include/linux/mfd/twl.h
- (have not checked): probably different register offsets
- has no remove/suspend/resume handlers (probably older WDT core API and
easy to copy&paste)
But there seems to be a bug in palmas_wdt_write(). IMHO it ignores the "data" argument when passing down to palmas_write()...
So it may be that the driver did not work as proposed.
I am not sure but I think I had spotted a v10 of the patch set.
Ah, yes:
https://lore.kernel.org/patchwork/patch/367819/
There are already several review comments (including confirmation of the data argument issue) but I could not find a v11 or v12.
Note that some devices just use drivers/watchdog/omap_wdt.c that is wired to the PMIC used. So maybe the Palmas WDT was just forgotten if it was not needed?
Maybe it was simply forgotten to be completed and resubmitted.
I am not sure if Graeme is still actively working on this topic. So I put him on CC.
TImageddon ended my access to the documentation on that chip as I was contracted for it. I never saw the actual release version of the chip :-(
Graeme
Hi Graeme,
Am 15.12.2018 um 10:01 schrieb Graeme Gregory gg@slimlogic.co.uk:
On Sat, 15 Dec 2018, at 7:50 AM, H. Nikolaus Schaller wrote:
Hi Tony,
Am 13.12.2018 um 19:14 schrieb Tony Lindgren tony@atomide.com:
- H. Nikolaus Schaller hns@goldelico.com [181208 21:35]:
Hi Tony, I had the OMAP5 running very very hot by a kernel hang (most likely a spinlock). And I wondered if there is no safety mechanism (watchdog timer).
I did a little research and there seems to be no WDT driver for the Palmas in mainline.
There was something:
https://lore.kernel.org/patchwork/patch/367777/
but it seems it did not arrive upstream. Any reasons or problems with the driver? Or a newer version sitting in some git?
Sorry no idea. Maybe check if it's similar to the drivers/watchdog/twl4030_wdt.c?
Yes, it is. Code structure is almost the same, because it is based on twl4030 code :)
Differences:
- uses enable/disable instead of start/stop (probably older WDT core API
and easy to fix)
- different compatible list (obviously necessary)
- uses palmas_write() from include/linux/mfd/palmas.h instead of
twl_i2c_write_u8() from include/linux/mfd/twl.h
- (have not checked): probably different register offsets
- has no remove/suspend/resume handlers (probably older WDT core API and
easy to copy&paste)
But there seems to be a bug in palmas_wdt_write(). IMHO it ignores the "data" argument when passing down to palmas_write()...
So it may be that the driver did not work as proposed.
I am not sure but I think I had spotted a v10 of the patch set.
Ah, yes:
https://lore.kernel.org/patchwork/patch/367819/
There are already several review comments (including confirmation of the data argument issue) but I could not find a v11 or v12.
Note that some devices just use drivers/watchdog/omap_wdt.c that is wired to the PMIC used. So maybe the Palmas WDT was just forgotten if it was not needed?
Maybe it was simply forgotten to be completed and resubmitted.
I am not sure if Graeme is still actively working on this topic. So I put him on CC.
TImageddon ended my access to the documentation on that chip as I was contracted for it. I never saw the actual release version of the chip :-(
Ok, I see...
Well, we hope the Pyra handheld will go to mass production soon. And IMHO the Palmas documentations are now available officially somewhere.
Anyways, I have pulled your patch and hope that I can make it working in the next weeks. I would be happy if you could participate in review when I try to get it upstream.
BR and thanks, Nikolaus
-
Graeme Gregory -
H. Nikolaus Schaller -
Tony Lindgren