[PATCH RESEND v3 0/2] syscon: Alter syscon and reboot drivers

[PATCH RESEND v3 0/2] syscon: Alter syscon and reboot drivers

[Serge Semin]

This is a small patchset about tuning the syscon infrastructure a bit.
As it's going to be general in the framework of the Baikal-T1 SoC support
integration into the kernel, we suggest to replace the legacy text-based
syscon-reboot-mode dts-bindings file with yaml-based one. Then seeing a
syscon reboot block is normally expected to be a part of a system
controller and based on the discussion
https://lore.kernel.org/linux-pm/20200306130402.1F4F0803079F@mail.baikalelectronics.ru/
we decided to alter the syscon reboot driver so one would also try to fetch
the syscon registers map from a parental DT node. regmap property is left
supported although it's marked as deprecated from now.

This patchset is rebased and tested on the mainline Linux kernel 5.7-rc4:
0e698dfa2822 ("Linux 5.7-rc4")
tag: v5.7-rc4

Changelog v2:
- Add Sebastian' Acked-by tag to patch 1.
- Use a shorter summary describing the bindings modification patches.
- Our corporate email server doesn't change Message-Id anymore, so the patchset
  is resubmitted being in the cover-letter-threaded format.
- Discard patch with syscon "-endian" property support. As Rob said It shall be
  in the common dt-schema.
- Replace patches of adding a regmap property support to the syscon-reboot-mode
  with patches making syscon-reboot a sub-node of a system controller node.
- Mark regmap property as deprecated from now.

Link: https://lore.kernel.org/linux-pm/20200507233846.11548-1-Sergey.Semin@baikalelectronics.ru/
Changelog v3:
- Discard the commit 6acd3ecd88ff ("dt-bindings: power: reset: Convert
  syscon-reboot-mode to DT schema") since it has been merged in by Sebatian.
- Add Rob's Reviewed-by tag to the patch "dt-bindings: power: reset: Unrequire
  regmap property in syscon-reboot node"

Signed-off-by: Serge Semin <Sergey.Semin@baikalelectronics.ru>
Cc: Alexey Malahov <Alexey.Malahov@baikalelectronics.ru>
Cc: Maxim Kaurkin <Maxim.Kaurkin@baikalelectronics.ru>
Cc: Pavel Parkhomenko <Pavel.Parkhomenko@baikalelectronics.ru>
Cc: Ramil Zaripov <Ramil.Zaripov@baikalelectronics.ru>
Cc: Ekaterina Skachko <Ekaterina.Skachko@baikalelectronics.ru>
Cc: Vadim Vlasov <V.Vlasov@baikalelectronics.ru>
Cc: Alexey Kolotnikov <Alexey.Kolotnikov@baikalelectronics.ru>
Cc: Thomas Bogendoerfer <tsbogend@alpha.franken.de>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Rob Herring <robh+dt@kernel.org>
Cc: linux-mips@vger.kernel.org
Cc: devicetree@vger.kernel.org
Cc: linux-pm@vger.kernel.org
Cc: linux-kernel@vger.kernel.org

Serge Semin (2):
  dt-bindings: power: reset: Unrequire regmap property in syscon-reboot
    node
  power: reset: syscon-reboot: Add parental syscon support

 .../bindings/power/reset/syscon-reboot.yaml       | 15 ++++++++++-----
 drivers/power/reset/syscon-reboot.c               |  7 +++++--
 2 files changed, 15 insertions(+), 7 deletions(-)

-- 
2.26.2

[PATCH v3 1/2] dt-bindings: power: reset: Unrequire regmap property in syscon-reboot node

[Serge Semin]

Since normally syscon-reboot block is supposed to be a part of a system
controller, lets mark the regmap property as deprecated and recommend the
syscon-reboot node to be a sub-node of SYSCON.

Signed-off-by: Serge Semin <Sergey.Semin@baikalelectronics.ru>
Reviewed-by: Rob Herring <robh@kernel.org>
Cc: Alexey Malahov <Alexey.Malahov@baikalelectronics.ru>
Cc: Thomas Bogendoerfer <tsbogend@alpha.franken.de>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: linux-mips@vger.kernel.org

---

Changelog v2:
- This is a new patch created as a result of the discussion:
  https://lore.kernel.org/linux-pm/20200306130402.1F4F0803079F@mail.baikalelectronics.ru/
---
 .../bindings/power/reset/syscon-reboot.yaml       | 15 ++++++++++-----
 1 file changed, 10 insertions(+), 5 deletions(-)

diff --git a/Documentation/devicetree/bindings/power/reset/syscon-reboot.yaml b/Documentation/devicetree/bindings/power/reset/syscon-reboot.yaml
index b80772cb9f06..da2509724812 100644
--- a/Documentation/devicetree/bindings/power/reset/syscon-reboot.yaml
+++ b/Documentation/devicetree/bindings/power/reset/syscon-reboot.yaml
@@ -12,9 +12,12 @@ maintainers:
 description: |+
   This is a generic reset driver using syscon to map the reset register.
   The reset is generally performed with a write to the reset register
-  defined by the register map pointed by syscon reference plus the offset
-  with the value and mask defined in the reboot node.
-  Default will be little endian mode, 32 bit access only.
+  defined by the SYSCON register map base plus the offset with the value and
+  mask defined in the reboot node. Default will be little endian mode, 32 bit
+  access only. The SYSCON registers map is normally retrieved from the
+  parental dt-node. So the SYSCON reboot node should be represented as a
+  sub-node of a "syscon", "simple-mfd" node. Though the regmap property
+  pointing to the system controller node is also supported.
 
 properties:
   compatible:
@@ -30,7 +33,10 @@ properties:
 
   regmap:
     $ref: /schemas/types.yaml#/definitions/phandle
-    description: Phandle to the register map node.
+    deprecated: true
+    description: |
+      Phandle to the register map node. This property is deprecated in favor of
+      the syscon-reboot node been a child of a system controller node.
 
   value:
     $ref: /schemas/types.yaml#/definitions/uint32
@@ -38,7 +44,6 @@ properties:
 
 required:
   - compatible
-  - regmap
   - offset
 
 additionalProperties: false
-- 
2.26.2

[PATCH v3 2/2] power: reset: syscon-reboot: Add parental syscon support

[Serge Semin]

Since normally syscon-reboot block is supposed to be a part of a system
controller, lets look for the syscon regmap in a parental DT node if
regmap property isn't specified. DT binding from now considers the regmap
property as deprecated.

Signed-off-by: Serge Semin <Sergey.Semin@baikalelectronics.ru>
Cc: Alexey Malahov <Alexey.Malahov@baikalelectronics.ru>
Cc: Thomas Bogendoerfer <tsbogend@alpha.franken.de>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Rob Herring <robh+dt@kernel.org>
Cc: linux-mips@vger.kernel.org
Cc: devicetree@vger.kernel.org

---

Changelog v2:
- This is a new patch created as a result of the discussion:
  https://lore.kernel.org/linux-pm/20200306130402.1F4F0803079F@mail.baikalelectronics.ru/

Changelog v3:
- Resend
---
 drivers/power/reset/syscon-reboot.c | 7 +++++--
 1 file changed, 5 insertions(+), 2 deletions(-)

diff --git a/drivers/power/reset/syscon-reboot.c b/drivers/power/reset/syscon-reboot.c
index 62fbba0df971..510e363381ca 100644
--- a/drivers/power/reset/syscon-reboot.c
+++ b/drivers/power/reset/syscon-reboot.c
@@ -51,8 +51,11 @@ static int syscon_reboot_probe(struct platform_device *pdev)
 		return -ENOMEM;
 
 	ctx->map = syscon_regmap_lookup_by_phandle(dev->of_node, "regmap");
-	if (IS_ERR(ctx->map))
-		return PTR_ERR(ctx->map);
+	if (IS_ERR(ctx->map)) {
+		ctx->map = syscon_node_to_regmap(dev->parent->of_node);
+		if (IS_ERR(ctx->map))
+			return PTR_ERR(ctx->map);
+	}
 
 	if (of_property_read_u32(pdev->dev.of_node, "offset", &ctx->offset))
 		return -EINVAL;
-- 
2.26.2

Re: [PATCH RESEND v3 0/2] syscon: Alter syscon and reboot drivers

[Sebastian Reichel]

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Hi,

On Tue, May 26, 2020 at 04:50:59PM +0300, Serge Semin wrote:
> This is a small patchset about tuning the syscon infrastructure a bit.
> As it's going to be general in the framework of the Baikal-T1 SoC support
> integration into the kernel, we suggest to replace the legacy text-based
> syscon-reboot-mode dts-bindings file with yaml-based one. Then seeing a
> syscon reboot block is normally expected to be a part of a system
> controller and based on the discussion
> https://lore.kernel.org/linux-pm/20200306130402.1F4F0803079F@mail.baikalelectronics.ru/
> we decided to alter the syscon reboot driver so one would also try to fetch
> the syscon registers map from a parental DT node. regmap property is left
> supported although it's marked as deprecated from now.
> 
> This patchset is rebased and tested on the mainline Linux kernel 5.7-rc4:
> 0e698dfa2822 ("Linux 5.7-rc4")
> tag: v5.7-rc4
> 
> Changelog v2:
> - Add Sebastian' Acked-by tag to patch 1.
> - Use a shorter summary describing the bindings modification patches.
> - Our corporate email server doesn't change Message-Id anymore, so the patchset
>   is resubmitted being in the cover-letter-threaded format.
> - Discard patch with syscon "-endian" property support. As Rob said It shall be
>   in the common dt-schema.
> - Replace patches of adding a regmap property support to the syscon-reboot-mode
>   with patches making syscon-reboot a sub-node of a system controller node.
> - Mark regmap property as deprecated from now.
> 
> Link: https://lore.kernel.org/linux-pm/20200507233846.11548-1-Sergey.Semin@baikalelectronics.ru/
> Changelog v3:
> - Discard the commit 6acd3ecd88ff ("dt-bindings: power: reset: Convert
>   syscon-reboot-mode to DT schema") since it has been merged in by Sebatian.
> - Add Rob's Reviewed-by tag to the patch "dt-bindings: power: reset: Unrequire
>   regmap property in syscon-reboot node"
> 
> Signed-off-by: Serge Semin <Sergey.Semin@baikalelectronics.ru>
> Cc: Alexey Malahov <Alexey.Malahov@baikalelectronics.ru>
> Cc: Maxim Kaurkin <Maxim.Kaurkin@baikalelectronics.ru>
> Cc: Pavel Parkhomenko <Pavel.Parkhomenko@baikalelectronics.ru>
> Cc: Ramil Zaripov <Ramil.Zaripov@baikalelectronics.ru>
> Cc: Ekaterina Skachko <Ekaterina.Skachko@baikalelectronics.ru>
> Cc: Vadim Vlasov <V.Vlasov@baikalelectronics.ru>
> Cc: Alexey Kolotnikov <Alexey.Kolotnikov@baikalelectronics.ru>
> Cc: Thomas Bogendoerfer <tsbogend@alpha.franken.de>
> Cc: Arnd Bergmann <arnd@arndb.de>
> Cc: Rob Herring <robh+dt@kernel.org>
> Cc: linux-mips@vger.kernel.org
> Cc: devicetree@vger.kernel.org
> Cc: linux-pm@vger.kernel.org
> Cc: linux-kernel@vger.kernel.org
> 
> Serge Semin (2):
>   dt-bindings: power: reset: Unrequire regmap property in syscon-reboot
>     node
>   power: reset: syscon-reboot: Add parental syscon support
> 
>  .../bindings/power/reset/syscon-reboot.yaml       | 15 ++++++++++-----
>  drivers/power/reset/syscon-reboot.c               |  7 +++++--
>  2 files changed, 15 insertions(+), 7 deletions(-)

Thanks, I queued both patches to power-supply's for-next branch.

-- Sebastian

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Re: [PATCH RESEND v3 0/2] syscon: Alter syscon and reboot drivers

[Serge Semin]

On Thu, May 28, 2020 at 09:03:11AM +0200, Sebastian Reichel wrote:
> Hi,
> 
> On Tue, May 26, 2020 at 04:50:59PM +0300, Serge Semin wrote:
> > This is a small patchset about tuning the syscon infrastructure a bit.
> > As it's going to be general in the framework of the Baikal-T1 SoC support
> > integration into the kernel, we suggest to replace the legacy text-based
> > syscon-reboot-mode dts-bindings file with yaml-based one. Then seeing a
> > syscon reboot block is normally expected to be a part of a system
> > controller and based on the discussion
> > https://lore.kernel.org/linux-pm/20200306130402.1F4F0803079F@mail.baikalelectronics.ru/
> > we decided to alter the syscon reboot driver so one would also try to fetch
> > the syscon registers map from a parental DT node. regmap property is left
> > supported although it's marked as deprecated from now.
> > 
> > This patchset is rebased and tested on the mainline Linux kernel 5.7-rc4:
> > 0e698dfa2822 ("Linux 5.7-rc4")
> > tag: v5.7-rc4
> > 
> > Changelog v2:
> > - Add Sebastian' Acked-by tag to patch 1.
> > - Use a shorter summary describing the bindings modification patches.
> > - Our corporate email server doesn't change Message-Id anymore, so the patchset
> >   is resubmitted being in the cover-letter-threaded format.
> > - Discard patch with syscon "-endian" property support. As Rob said It shall be
> >   in the common dt-schema.
> > - Replace patches of adding a regmap property support to the syscon-reboot-mode
> >   with patches making syscon-reboot a sub-node of a system controller node.
> > - Mark regmap property as deprecated from now.
> > 
> > Link: https://lore.kernel.org/linux-pm/20200507233846.11548-1-Sergey.Semin@baikalelectronics.ru/
> > Changelog v3:
> > - Discard the commit 6acd3ecd88ff ("dt-bindings: power: reset: Convert
> >   syscon-reboot-mode to DT schema") since it has been merged in by Sebatian.
> > - Add Rob's Reviewed-by tag to the patch "dt-bindings: power: reset: Unrequire
> >   regmap property in syscon-reboot node"
> > 
> > Signed-off-by: Serge Semin <Sergey.Semin@baikalelectronics.ru>
> > Cc: Alexey Malahov <Alexey.Malahov@baikalelectronics.ru>
> > Cc: Maxim Kaurkin <Maxim.Kaurkin@baikalelectronics.ru>
> > Cc: Pavel Parkhomenko <Pavel.Parkhomenko@baikalelectronics.ru>
> > Cc: Ramil Zaripov <Ramil.Zaripov@baikalelectronics.ru>
> > Cc: Ekaterina Skachko <Ekaterina.Skachko@baikalelectronics.ru>
> > Cc: Vadim Vlasov <V.Vlasov@baikalelectronics.ru>
> > Cc: Alexey Kolotnikov <Alexey.Kolotnikov@baikalelectronics.ru>
> > Cc: Thomas Bogendoerfer <tsbogend@alpha.franken.de>
> > Cc: Arnd Bergmann <arnd@arndb.de>
> > Cc: Rob Herring <robh+dt@kernel.org>
> > Cc: linux-mips@vger.kernel.org
> > Cc: devicetree@vger.kernel.org
> > Cc: linux-pm@vger.kernel.org
> > Cc: linux-kernel@vger.kernel.org
> > 
> > Serge Semin (2):
> >   dt-bindings: power: reset: Unrequire regmap property in syscon-reboot
> >     node
> >   power: reset: syscon-reboot: Add parental syscon support
> > 
> >  .../bindings/power/reset/syscon-reboot.yaml       | 15 ++++++++++-----
> >  drivers/power/reset/syscon-reboot.c               |  7 +++++--
> >  2 files changed, 15 insertions(+), 7 deletions(-)
> 
> Thanks, I queued both patches to power-supply's for-next branch.
> 
> -- Sebastian

Great! Thanks.

-Sergey