kernel: backport upstream nvmem fix for "fixed-layout"

It replaces a pretty much identical downstream patch.

Signed-off-by: Rafał Miłecki <rafal@milecki.pl>

4 files changed, 90 insertions, 80 deletions

diff --git a/target/linux/generic/backport-5.15/820-v6.7-0005-nvmem-Do-not-expect-fixed-layouts-to-grab-a-layout-d.patch b/target/linux/generic/backport-5.15/820-v6.7-0005-nvmem-Do-not-expect-fixed-layouts-to-grab-a-layout-d.patch
new file mode 100644
index 0000000000..bd5ceaabf7
--- /dev/null
+++ b/target/linux/generic/backport-5.15/820-v6.7-0005-nvmem-Do-not-expect-fixed-layouts-to-grab-a-layout-d.patch
@@ -0,0 +1,45 @@
+From b7c1e53751cb3990153084f31c41f25fde3b629c Mon Sep 17 00:00:00 2001
+From: Miquel Raynal <miquel.raynal@bootlin.com>
+Date: Fri, 24 Nov 2023 20:38:14 +0100
+Subject: [PATCH] nvmem: Do not expect fixed layouts to grab a layout driver
+MIME-Version: 1.0
+Content-Type: text/plain; charset=UTF-8
+Content-Transfer-Encoding: 8bit
+
+Two series lived in parallel for some time, which led to this situation:
+- The nvmem-layout container is used for dynamic layouts
+- We now expect fixed layouts to also use the nvmem-layout container but
+this does not require any additional driver, the support is built-in the
+nvmem core.
+
+Ensure we don't refuse to probe for wrong reasons.
+
+Fixes: 27f699e578b1 ("nvmem: core: add support for fixed cells *layout*")
+Cc: stable@vger.kernel.org
+Reported-by: Luca Ceresoli <luca.ceresoli@bootlin.com>
+Signed-off-by: Miquel Raynal <miquel.raynal@bootlin.com>
+Tested-by: Rafał Miłecki <rafal@milecki.pl>
+Tested-by: Luca Ceresoli <luca.ceresoli@bootlin.com>
+Reviewed-by: Luca Ceresoli <luca.ceresoli@bootlin.com>
+
+Link: https://lore.kernel.org/r/20231124193814.360552-1-miquel.raynal@bootlin.com
+Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
+---
+ drivers/nvmem/core.c | 6 ++++++
+ 1 file changed, 6 insertions(+)
+
+--- a/drivers/nvmem/core.c
++++ b/drivers/nvmem/core.c
+@@ -797,6 +797,12 @@ static struct nvmem_layout *nvmem_layout
+ 	if (!layout_np)
+ 		return NULL;
+ 
++	/* Fixed layouts don't have a matching driver */
++	if (of_device_is_compatible(layout_np, "fixed-layout")) {
++		of_node_put(layout_np);
++		return NULL;
++	}
++
+ 	/*
+ 	 * In case the nvmem device was built-in while the layout was built as a
+ 	 * module, we shall manually request the layout driver loading otherwise
diff --git a/target/linux/generic/backport-6.1/816-v6.7-0005-nvmem-Do-not-expect-fixed-layouts-to-grab-a-layout-d.patch b/target/linux/generic/backport-6.1/816-v6.7-0005-nvmem-Do-not-expect-fixed-layouts-to-grab-a-layout-d.patch
new file mode 100644
index 0000000000..bd5ceaabf7
--- /dev/null
+++ b/target/linux/generic/backport-6.1/816-v6.7-0005-nvmem-Do-not-expect-fixed-layouts-to-grab-a-layout-d.patch
@@ -0,0 +1,45 @@
+From b7c1e53751cb3990153084f31c41f25fde3b629c Mon Sep 17 00:00:00 2001
+From: Miquel Raynal <miquel.raynal@bootlin.com>
+Date: Fri, 24 Nov 2023 20:38:14 +0100
+Subject: [PATCH] nvmem: Do not expect fixed layouts to grab a layout driver
+MIME-Version: 1.0
+Content-Type: text/plain; charset=UTF-8
+Content-Transfer-Encoding: 8bit
+
+Two series lived in parallel for some time, which led to this situation:
+- The nvmem-layout container is used for dynamic layouts
+- We now expect fixed layouts to also use the nvmem-layout container but
+this does not require any additional driver, the support is built-in the
+nvmem core.
+
+Ensure we don't refuse to probe for wrong reasons.
+
+Fixes: 27f699e578b1 ("nvmem: core: add support for fixed cells *layout*")
+Cc: stable@vger.kernel.org
+Reported-by: Luca Ceresoli <luca.ceresoli@bootlin.com>
+Signed-off-by: Miquel Raynal <miquel.raynal@bootlin.com>
+Tested-by: Rafał Miłecki <rafal@milecki.pl>
+Tested-by: Luca Ceresoli <luca.ceresoli@bootlin.com>
+Reviewed-by: Luca Ceresoli <luca.ceresoli@bootlin.com>
+
+Link: https://lore.kernel.org/r/20231124193814.360552-1-miquel.raynal@bootlin.com
+Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
+---
+ drivers/nvmem/core.c | 6 ++++++
+ 1 file changed, 6 insertions(+)
+
+--- a/drivers/nvmem/core.c
++++ b/drivers/nvmem/core.c
+@@ -797,6 +797,12 @@ static struct nvmem_layout *nvmem_layout
+ 	if (!layout_np)
+ 		return NULL;
+ 
++	/* Fixed layouts don't have a matching driver */
++	if (of_device_is_compatible(layout_np, "fixed-layout")) {
++		of_node_put(layout_np);
++		return NULL;
++	}
++
+ 	/*
+ 	 * In case the nvmem device was built-in while the layout was built as a
+ 	 * module, we shall manually request the layout driver loading otherwise
diff --git a/target/linux/generic/pending-5.15/803-nvmem-core-fix-support-for-fixed-cells-NVMEM-layout.patch b/target/linux/generic/pending-5.15/803-nvmem-core-fix-support-for-fixed-cells-NVMEM-layout.patch
deleted file mode 100644
index f403bbec9b..0000000000
--- a/target/linux/generic/pending-5.15/803-nvmem-core-fix-support-for-fixed-cells-NVMEM-layout.patch
+++ /dev/null
@@ -1,40 +0,0 @@
-From: =?UTF-8?q?Rafa=C5=82=20Mi=C5=82ecki?= <rafal@milecki.pl>
-Date: Thu, 13 Jul 2023 17:30:59 +0200
-Subject: [PATCH] nvmem: core: fix support for fixed cells NVMEM layout
-MIME-Version: 1.0
-Content-Type: text/plain; charset=UTF-8
-Content-Transfer-Encoding: 8bit
-
-Returning -EPROBE_DEFER for "fixed-layout" makes nvmem_register() always
-fail (that layout is supported internally with no external module). That
-makes callers (e.g. mtd_nvmem_add()) fail as well and prevents booting
-on devices with "fixed-layout" in DT.
-
-Add a quick workaround for it.
-
-Fixes: 6468a6f45148 ("nvmem: core: handle the absence of expected layouts")
-Signed-off-by: Rafał Miłecki <rafal@milecki.pl>
----
-
---- a/drivers/nvmem/core.c
-+++ b/drivers/nvmem/core.c
-@@ -798,6 +798,19 @@ static struct nvmem_layout *nvmem_layout
- 		return NULL;
- 
- 	/*
-+	 * We should return -EPROBE_DEFER only when layout driver is expected to
-+	 * become available later. Otherwise NVMEM will never probe successfully
-+	 * for unsupported layouts. There is no known solution for that right
-+	 * now.
-+	 *
-+	 * This problem also affects "fixed-layout". It's supported in NVMEM
-+	 * core code so there never will be layout for it. We shouldn't return
-+	 * -EPROBE_DEFER in such case. Add a quick workaround for that.
-+	 */
-+	if (of_device_is_compatible(layout_np, "fixed-layout"))
-+		return NULL;
-+
-+	/*
- 	 * In case the nvmem device was built-in while the layout was built as a
- 	 * module, we shall manually request the layout driver loading otherwise
- 	 * we'll never have any match.
diff --git a/target/linux/generic/pending-6.1/803-nvmem-core-fix-support-for-fixed-cells-NVMEM-layout.patch b/target/linux/generic/pending-6.1/803-nvmem-core-fix-support-for-fixed-cells-NVMEM-layout.patch
deleted file mode 100644
index f403bbec9b..0000000000
--- a/target/linux/generic/pending-6.1/803-nvmem-core-fix-support-for-fixed-cells-NVMEM-layout.patch
+++ /dev/null
@@ -1,40 +0,0 @@
-From: =?UTF-8?q?Rafa=C5=82=20Mi=C5=82ecki?= <rafal@milecki.pl>
-Date: Thu, 13 Jul 2023 17:30:59 +0200
-Subject: [PATCH] nvmem: core: fix support for fixed cells NVMEM layout
-MIME-Version: 1.0
-Content-Type: text/plain; charset=UTF-8
-Content-Transfer-Encoding: 8bit
-
-Returning -EPROBE_DEFER for "fixed-layout" makes nvmem_register() always
-fail (that layout is supported internally with no external module). That
-makes callers (e.g. mtd_nvmem_add()) fail as well and prevents booting
-on devices with "fixed-layout" in DT.
-
-Add a quick workaround for it.
-
-Fixes: 6468a6f45148 ("nvmem: core: handle the absence of expected layouts")
-Signed-off-by: Rafał Miłecki <rafal@milecki.pl>
----
-
---- a/drivers/nvmem/core.c
-+++ b/drivers/nvmem/core.c
-@@ -798,6 +798,19 @@ static struct nvmem_layout *nvmem_layout
- 		return NULL;
- 
- 	/*
-+	 * We should return -EPROBE_DEFER only when layout driver is expected to
-+	 * become available later. Otherwise NVMEM will never probe successfully
-+	 * for unsupported layouts. There is no known solution for that right
-+	 * now.
-+	 *
-+	 * This problem also affects "fixed-layout". It's supported in NVMEM
-+	 * core code so there never will be layout for it. We shouldn't return
-+	 * -EPROBE_DEFER in such case. Add a quick workaround for that.
-+	 */
-+	if (of_device_is_compatible(layout_np, "fixed-layout"))
-+		return NULL;
-+
-+	/*
- 	 * In case the nvmem device was built-in while the layout was built as a
- 	 * module, we shall manually request the layout driver loading otherwise
- 	 * we'll never have any match.