Re: [PATCH] i2c: designware: Fix functionality in !CONFIG_ACPI case
On Tue, Jun 23, 2020 at 10:59:40AM +0300, Jarkko Nikula wrote:
> Hi
>
> On 6/23/20 5:51 AM, John Stultz wrote:
> > On the HiKey board, where CONFIG_ACPI is not set, we started
> > to see a graphics regression where the adv7511 HDMI bridge driver
> > wasn't probing. This was due to the i2c bus failing to start up.
> >
> > I bisected the problem down to commit f9288fcc5c615 ("i2c:
> > designware: Move ACPI parts into common module") and after
> > looking at it a bit, I realized that change moved some
> > initialization into i2c_dw_acpi_adjust_bus_speed(). However,
> > i2c_dw_acpi_adjust_bus_speed() is only functional if CONFIG_ACPI
> > is set.
> >
> > This patch pulls i2c_dw_acpi_adjust_bus_speed() out of the
> > ifdef CONFIG_ACPI conditional, and gets the board working again.
> >
> > Cc: Andy Shevchenko
> > Cc: Jarkko Nikula
> > Cc: Wolfram Sang
> > Cc: linux-...@vger.kernel.org
> > Fixes: f9288fcc5c615 ("i2c: designware: Move ACPI parts into common module")
> > Signed-off-by: John Stultz
> > ---
> > drivers/i2c/busses/i2c-designware-common.c | 4 ++--
> > drivers/i2c/busses/i2c-designware-core.h | 3 +--
> > 2 files changed, 3 insertions(+), 4 deletions(-)
> >
> > diff --git a/drivers/i2c/busses/i2c-designware-common.c
> > b/drivers/i2c/busses/i2c-designware-common.c
> > index e3a8640db7da..33de185e15f2 100644
> > --- a/drivers/i2c/busses/i2c-designware-common.c
> > +++ b/drivers/i2c/busses/i2c-designware-common.c
> > @@ -286,6 +286,8 @@ int i2c_dw_acpi_configure(struct device *device)
> > }
> > EXPORT_SYMBOL_GPL(i2c_dw_acpi_configure);
> > +#endif /* CONFIG_ACPI */
> > +
>
> I think the regression is in these lines below that were moved from probe to
> i2c_dw_acpi_adjust_bus_speed() and cause that neither "cloock-frequency"
> device property or I2C_MAX_FAST_MODE_FREQ affect the bus speed when
> CONFIG_ACPI is not set.
>
> + /*
> +* Find bus speed from the "clock-frequency" device property, ACPI
> +* or by using fast mode if neither is set.
> +*/
> + if (acpi_speed && t->bus_freq_hz)
> + t->bus_freq_hz = min(t->bus_freq_hz, acpi_speed);
> + else if (acpi_speed || t->bus_freq_hz)
> + t->bus_freq_hz = max(t->bus_freq_hz, acpi_speed);
> + else
> + t->bus_freq_hz = I2C_MAX_FAST_MODE_FREQ;
>
> Andy: what you think should the i2c_dw_acpi_adjust_bus_speed() fixed to
> return adjusted speed or zero if not found (also for !CONFIG_ACPI) and move
> above lines back to probe? It looks more clear to me that way and should fix
> the regression I think.
I have split it to two functions and renamed accordingly. Will send patch soon,
after some testing.
--
With Best Regards,
Andy Shevchenko
Re: [PATCH] i2c: designware: Fix functionality in !CONFIG_ACPI case
On 6/23/20 10:59 AM, Jarkko Nikula wrote:
Hi
On 6/23/20 5:51 AM, John Stultz wrote:
On the HiKey board, where CONFIG_ACPI is not set, we started
to see a graphics regression where the adv7511 HDMI bridge driver
wasn't probing. This was due to the i2c bus failing to start up.
I bisected the problem down to commit f9288fcc5c615 ("i2c:
designware: Move ACPI parts into common module") and after
looking at it a bit, I realized that change moved some
initialization into i2c_dw_acpi_adjust_bus_speed(). However,
i2c_dw_acpi_adjust_bus_speed() is only functional if CONFIG_ACPI
is set.
This patch pulls i2c_dw_acpi_adjust_bus_speed() out of the
ifdef CONFIG_ACPI conditional, and gets the board working again.
Andy: what you think should the i2c_dw_acpi_adjust_bus_speed() fixed to
return adjusted speed or zero if not found (also for !CONFIG_ACPI) and
move above lines back to probe? It looks more clear to me that way and
should fix the regression I think.
Ok, I sent a patch what I was thinking. Care to test John does it fix
the regression you are seeing?
--
Jarkko
Re: [PATCH] i2c: designware: Fix functionality in !CONFIG_ACPI case
Hi
On 6/23/20 5:51 AM, John Stultz wrote:
On the HiKey board, where CONFIG_ACPI is not set, we started
to see a graphics regression where the adv7511 HDMI bridge driver
wasn't probing. This was due to the i2c bus failing to start up.
I bisected the problem down to commit f9288fcc5c615 ("i2c:
designware: Move ACPI parts into common module") and after
looking at it a bit, I realized that change moved some
initialization into i2c_dw_acpi_adjust_bus_speed(). However,
i2c_dw_acpi_adjust_bus_speed() is only functional if CONFIG_ACPI
is set.
This patch pulls i2c_dw_acpi_adjust_bus_speed() out of the
ifdef CONFIG_ACPI conditional, and gets the board working again.
Cc: Andy Shevchenko
Cc: Jarkko Nikula
Cc: Wolfram Sang
Cc: linux-...@vger.kernel.org
Fixes: f9288fcc5c615 ("i2c: designware: Move ACPI parts into common module")
Signed-off-by: John Stultz
---
drivers/i2c/busses/i2c-designware-common.c | 4 ++--
drivers/i2c/busses/i2c-designware-core.h | 3 +--
2 files changed, 3 insertions(+), 4 deletions(-)
diff --git a/drivers/i2c/busses/i2c-designware-common.c
b/drivers/i2c/busses/i2c-designware-common.c
index e3a8640db7da..33de185e15f2 100644
--- a/drivers/i2c/busses/i2c-designware-common.c
+++ b/drivers/i2c/busses/i2c-designware-common.c
@@ -286,6 +286,8 @@ int i2c_dw_acpi_configure(struct device *device)
}
EXPORT_SYMBOL_GPL(i2c_dw_acpi_configure);
+#endif /* CONFIG_ACPI */
+
I think the regression is in these lines below that were moved from
probe to i2c_dw_acpi_adjust_bus_speed() and cause that neither
"cloock-frequency" device property or I2C_MAX_FAST_MODE_FREQ affect the
bus speed when CONFIG_ACPI is not set.
+ /*
+* Find bus speed from the "clock-frequency" device property, ACPI
+* or by using fast mode if neither is set.
+*/
+ if (acpi_speed && t->bus_freq_hz)
+ t->bus_freq_hz = min(t->bus_freq_hz, acpi_speed);
+ else if (acpi_speed || t->bus_freq_hz)
+ t->bus_freq_hz = max(t->bus_freq_hz, acpi_speed);
+ else
+ t->bus_freq_hz = I2C_MAX_FAST_MODE_FREQ;
Andy: what you think should the i2c_dw_acpi_adjust_bus_speed() fixed to
return adjusted speed or zero if not found (also for !CONFIG_ACPI) and
move above lines back to probe? It looks more clear to me that way and
should fix the regression I think.
--
Jarkko
