Re: [RFT 00/10] pinctrl: samsung: Remove ugly hack for sharing eint_wakeup_mask

From: Tomasz Figa
Date: Fri Jul 20 2018 - 22:38:09 EST


Hi Krzysztof,

2018å7æ20æ(é) 1:01 Krzysztof Kozlowski <krzk@xxxxxxxxxx>:
>
> Hi All,
>
> Tests
> =====
> This is both request for comments and requests for tests. Only basic
> tests were done, including suspend to RAM on Odroid U3 (Exynos4412)
> with max7768 RTC wakeup. Please kindly test it with devices capable of
> suspending and resuming. I am mostly thinking about S5Pv210-based (Aria),
> Trats, Trats2 and TM2 (Exynos5433). Existing platforms should not be
> broken however changing external interrupt wakeup mask was not done
> on Exynos5433.
>
>
> Description
> ===========
> The Exynos/S5Pv210 machine suspend code needs to write the external
> interrupt mask during suspend. The mask is controlled by pin controller
> driver: the exynos_wkup_irq_set_wake() in IRQ chip for these wakeup
> interrupts.
>
> Therefore pinctrl driver code exposed an exynos_get_eint_wake_mask()
> function which was later used as an extern in machine code.
>
> This is quite ugly way of combining driver and machine code,
> not portable triggering Sparse and GCC warnings.
>
>
> This might break suspend capability S5Pv210 on with older DTBs (thus
> breaks DTB compatibility), however:
> 1. just "might" because in case of using older DTB, the wakeup mask
> will not be changed during suspend and default reset value (all
> interrupts non-masked) should work,
> 2. mainline support for S5Pv210 with DTB is limited and suspend
> to RAM already might be broken.

We probably should also add that it's highly unlikely that anyone
using S5PV210 actually uses a standalone DTB, since those systems
normally predated DT support in bootloaders and workarounds such as
chainloading or appended DTB are normally used.

>
>
> Dependencies
> ============
> 1. The first seven patches should be taken through one tree,
> preferably samsung-pinctrl,
> 2. The DTS patch (7/10) for S5Pv210 should go into next cycle,
> 3. The remaining patches (8-10) should go after all previous,
> so probably another release cycle.
>
>
> Best regards,
> Krzysztof
>
>
> Krzysztof Kozlowski (10):
> pinctrl: samsung: Define suspend and resume callbacks for all banks
> and SoCs
> pinctrl: samsung: Document suspend and resume members
> pinctrl: samsung: Document hidden requirement about one external
> wakeup
> pinctrl: samsung: Add dedicated compatible for S5Pv210 wakeup
> interrupts
> ARM: exynos: Define EINT_WAKEUP_MASK registers for S5Pv210 and
> Exynos5433
> pinctrl: samsung: Write external interrupt mask
> ARM: dts: s5pv210: Switch to S5Pv210 specific pinctrl wakeup
> compatible
> ARM: s5pv210: Remove legacy setting of external wakeup interrupts
> ARM: exynos: Remove legacy setting of external wakeup interrupts
> pinctrl: samsung: Remove legacy API for handling external wakeup
> interrupts mask
>
> .../bindings/pinctrl/samsung-pinctrl.txt | 11 ++-
> arch/arm/boot/dts/s5pv210.dtsi | 2 +-
> arch/arm/mach-exynos/common.h | 2 -
> arch/arm/mach-exynos/suspend.c | 16 +++--
> arch/arm/mach-s5pv210/common.h | 1 -
> arch/arm/mach-s5pv210/pm.c | 16 +++--
> drivers/pinctrl/samsung/pinctrl-exynos-arm.c | 16 +++++
> drivers/pinctrl/samsung/pinctrl-exynos.c | 78 +++++++++++++++++++---
> drivers/pinctrl/samsung/pinctrl-samsung.h | 11 +++
> include/linux/soc/samsung/exynos-regs-pmu.h | 8 ++-
> 10 files changed, 136 insertions(+), 25 deletions(-)

Looking through the series, the idea seems to be very reasonable, so:

Acked-by: Tomasz Figa <tomasz.figa@xxxxxxxxx>

Thanks for cleaning this up!

Best regards,
Tomasz