diff options
Diffstat (limited to 'target/linux/generic/backport-5.15/811-v6.4-0004-nvmem-core-request-layout-modules-loading.patch')
| -rw-r--r-- | target/linux/generic/backport-5.15/811-v6.4-0004-nvmem-core-request-layout-modules-loading.patch | 52 |
1 files changed, 52 insertions, 0 deletions
diff --git a/target/linux/generic/backport-5.15/811-v6.4-0004-nvmem-core-request-layout-modules-loading.patch b/target/linux/generic/backport-5.15/811-v6.4-0004-nvmem-core-request-layout-modules-loading.patch new file mode 100644 index 0000000000..b9341666f9 --- /dev/null +++ b/target/linux/generic/backport-5.15/811-v6.4-0004-nvmem-core-request-layout-modules-loading.patch @@ -0,0 +1,52 @@ +From b1c37bec1ccfe5ccab72bc0ddc0dfa45c43e2de2 Mon Sep 17 00:00:00 2001 +From: Miquel Raynal <miquel.raynal@bootlin.com> +Date: Tue, 4 Apr 2023 18:21:23 +0100 +Subject: [PATCH] nvmem: core: request layout modules loading + +When a storage device like an eeprom or an mtd device probes, it +registers an nvmem device if the nvmem subsystem has been enabled (bool +symbol). During nvmem registration, if the device is using layouts to +expose dynamic nvmem cells, the core will first try to get a reference +over the layout driver callbacks. In practice there is not relationship +that can be described between the storage driver and the nvmem +layout. So there is no way we can enforce both drivers will be built-in +or both will be modules. If the storage device driver is built-in but +the layout is built as a module, instead of badly failing with an +endless probe deferral loop, lets just make a modprobe call in case the +driver was made available in an initramfs with +of_device_node_request_module(), and offer a fully functional system to +the user. + +Signed-off-by: Miquel Raynal <miquel.raynal@bootlin.com> +Tested-by: Michael Walle <michael@walle.cc> +Signed-off-by: Srinivas Kandagatla <srinivas.kandagatla@linaro.org> +Link: https://lore.kernel.org/r/20230404172148.82422-16-srinivas.kandagatla@linaro.org +Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> +--- + drivers/nvmem/core.c | 8 ++++++++ + 1 file changed, 8 insertions(+) + +--- a/drivers/nvmem/core.c ++++ b/drivers/nvmem/core.c +@@ -17,6 +17,7 @@ + #include <linux/nvmem-provider.h> + #include <linux/gpio/consumer.h> + #include <linux/of.h> ++#include <linux/of_device.h> + #include <linux/slab.h> + + struct nvmem_device { +@@ -761,6 +762,13 @@ static struct nvmem_layout *nvmem_layout + if (!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 ++ * we'll never have any match. ++ */ ++ of_request_module(layout_np); ++ + spin_lock(&nvmem_layout_lock); + + list_for_each_entry(l, &nvmem_layouts, node) { |