Received-SPF: pass (google.com: domain of linux-kernel-owner@vger.kernel.org designates 2620:137:e000::1:20 as permitted sender) client-ip=2620:137:e000::1:20;
From:   Benjamin Bara <bbara93@gmail.com>
Subject: [PATCH v3 0/4] mfd: tps6586x: register restart handler
Date:   Mon, 27 Mar 2023 15:57:42 +0200
Message-Id: <20230327-tegra-pmic-reboot-v3-0-3c0ee3567e14@skidata.com>
MIME-Version: 1.0
Content-Type: text/plain; charset="utf-8"
Content-Transfer-Encoding: 7bit
To:     Wolfram Sang <wsa@kernel.org>, Lee Jones <lee@kernel.org>,
        rafael.j.wysocki@intel.com
Cc:     dmitry.osipenko@collabora.com, jonathanh@nvidia.com,
        richard.leitner@linux.dev, treding@nvidia.com,
        linux-kernel@vger.kernel.org, linux-i2c@vger.kernel.org,
        linux-tegra@vger.kernel.org,
        Benjamin Bara <benjamin.bara@skidata.com>,
        stable@vger.kernel.org
Precedence: bulk

Hi!

The Tegra20 requires an enabled VDE power domain during startup.
As the VDE is currently not used, it is disabled during runtime.
Since [1], there is a workaround for the "normal restart path" which
enables the VDE before doing PMC's warm reboot.
This workaround is not executed in the "emergency restart path", leading
to a hang-up during start.

This series implements and registers a new pmic-based restart handler for
boards with tps6586x.
This cold reboot ensures that the VDE power domain is enabled on
tegra20-based boards.

During panic(), preemption is disabled.
This should be correctly detected by i2c_in_atomic_xfer_mode() to use
atomic i2c xfer in this late stage. This avoids warnings regarding
"Voluntary context switch within RCU".

[1] 8f0c714ad9be1ef774c98e8819a7a571451cb019
v2: https://lore.kernel.org/all/20230320220345.1463687-1-bbara93@gmail.com/
system_state: https://lore.kernel.org/all/20230320213230.1459532-1-bbara93@gmail.com/
v1: https://lore.kernel.org/all/20230316164703.1157813-1-bbara93@gmail.com/

v3:
- bring system_state back in this series
- do atomic i2c xfer if not preemptible (as suggested by Dmitry)
- fix style issues mentioned by Dmitry
- add cc stable as suggested by Dmitry
- add explanation why this is needed for Jon

v2:
- use devm-based restart handler
- convert the existing power_off handler to a devm-based handler
- handle system_state in extra series

---
Benjamin Bara (4):
      kernel/reboot: emergency_restart: set correct system_state
      i2c: core: run atomic i2c xfer when !preemptible
      mfd: tps6586x: use devm-based power off handler
      mfd: tps6586x: register restart handler

 drivers/i2c/i2c-core.h |  2 +-
 drivers/mfd/tps6586x.c | 43 +++++++++++++++++++++++++++++++++++--------
 kernel/reboot.c        |  1 +
 3 files changed, 37 insertions(+), 9 deletions(-)
---
base-commit: 197b6b60ae7bc51dd0814953c562833143b292aa
change-id: 20230327-tegra-pmic-reboot-4175ff814a4b

Best regards,
-- 
Benjamin Bara <benjamin.bara@skidata.com>