mirror of https://github.com/hak5/openwrt.git
217 lines
5.7 KiB
Diff
217 lines
5.7 KiB
Diff
From e53f712d8eac71f54399b61038ccf87d2cee99d7 Mon Sep 17 00:00:00 2001
|
|
From: Bernhard Frauendienst <kernel@nospam.obeliks.de>
|
|
Date: Sat, 25 Aug 2018 12:35:22 +0200
|
|
Subject: [PATCH 497/497] mtd: mtdconcat: add dt driver for concat devices
|
|
|
|
Some mtd drivers like physmap variants have support for concatenating
|
|
multiple mtd devices, but there is no generic way to define such a
|
|
concat device from within the device tree.
|
|
|
|
This is useful for some SoC boards that use multiple flash chips as
|
|
memory banks of a single mtd device, with partitions spanning chip
|
|
borders.
|
|
|
|
This commit adds a driver for creating virtual mtd-concat devices. They
|
|
must have a compatible = "mtd-concat" line, and define a list of devices
|
|
to concat in the 'devices' property, for example:
|
|
|
|
flash {
|
|
compatible = "mtd-concat";
|
|
|
|
devices = <&flash0 &flash1>;
|
|
|
|
partitions {
|
|
...
|
|
};
|
|
};
|
|
|
|
The driver is added to the very end of the mtd Makefile to increase the
|
|
likelyhood of all child devices already being loaded at the time of
|
|
probing, preventing unnecessary deferred probes.
|
|
|
|
Signed-off-by: Bernhard Frauendienst <kernel@nospam.obeliks.de>
|
|
---
|
|
drivers/mtd/Kconfig | 2 +
|
|
drivers/mtd/Makefile | 3 +
|
|
drivers/mtd/composite/Kconfig | 12 +++
|
|
drivers/mtd/composite/Makefile | 6 ++
|
|
drivers/mtd/composite/virt_concat.c | 128 ++++++++++++++++++++++++++++
|
|
5 files changed, 151 insertions(+)
|
|
create mode 100644 drivers/mtd/composite/Kconfig
|
|
create mode 100644 drivers/mtd/composite/Makefile
|
|
create mode 100644 drivers/mtd/composite/virt_concat.c
|
|
|
|
--- a/drivers/mtd/Kconfig
|
|
+++ b/drivers/mtd/Kconfig
|
|
@@ -377,4 +377,6 @@ source "drivers/mtd/spi-nor/Kconfig"
|
|
|
|
source "drivers/mtd/ubi/Kconfig"
|
|
|
|
+source "drivers/mtd/composite/Kconfig"
|
|
+
|
|
endif # MTD
|
|
--- a/drivers/mtd/Makefile
|
|
+++ b/drivers/mtd/Makefile
|
|
@@ -39,3 +39,6 @@ obj-y += chips/ lpddr/ maps/ devices/ n
|
|
|
|
obj-$(CONFIG_MTD_SPI_NOR) += spi-nor/
|
|
obj-$(CONFIG_MTD_UBI) += ubi/
|
|
+
|
|
+# Composite drivers must be loaded last
|
|
+obj-y += composite/
|
|
--- /dev/null
|
|
+++ b/drivers/mtd/composite/Kconfig
|
|
@@ -0,0 +1,12 @@
|
|
+menu "Composite MTD device drivers"
|
|
+ depends on MTD!=n
|
|
+
|
|
+config MTD_VIRT_CONCAT
|
|
+ tristate "Virtual concat MTD device"
|
|
+ help
|
|
+ This driver allows creation of a virtual MTD concat device, which
|
|
+ concatenates multiple underlying MTD devices to a single device.
|
|
+ This is required by some SoC boards where multiple memory banks are
|
|
+ used as one device with partitions spanning across device boundaries.
|
|
+
|
|
+endmenu
|
|
--- /dev/null
|
|
+++ b/drivers/mtd/composite/Makefile
|
|
@@ -0,0 +1,6 @@
|
|
+# SPDX-License-Identifier: GPL-2.0
|
|
+#
|
|
+# linux/drivers/mtd/composite/Makefile
|
|
+#
|
|
+
|
|
+obj-$(CONFIG_MTD_VIRT_CONCAT) += virt_concat.o
|
|
--- /dev/null
|
|
+++ b/drivers/mtd/composite/virt_concat.c
|
|
@@ -0,0 +1,128 @@
|
|
+// SPDX-License-Identifier: GPL-2.0+
|
|
+/*
|
|
+ * Virtual concat MTD device driver
|
|
+ *
|
|
+ * Copyright (C) 2018 Bernhard Frauendienst
|
|
+ * Author: Bernhard Frauendienst, kernel@nospam.obeliks.de
|
|
+ */
|
|
+
|
|
+#include <linux/module.h>
|
|
+#include <linux/device.h>
|
|
+#include <linux/mtd/concat.h>
|
|
+#include <linux/mtd/mtd.h>
|
|
+#include <linux/mtd/partitions.h>
|
|
+#include <linux/of.h>
|
|
+#include <linux/of_platform.h>
|
|
+#include <linux/slab.h>
|
|
+
|
|
+/*
|
|
+ * struct of_virt_concat - platform device driver data.
|
|
+ * @cmtd the final mtd_concat device
|
|
+ * @num_devices the number of devices in @devices
|
|
+ * @devices points to an array of devices already loaded
|
|
+ */
|
|
+struct of_virt_concat {
|
|
+ struct mtd_info *cmtd;
|
|
+ int num_devices;
|
|
+ struct mtd_info **devices;
|
|
+};
|
|
+
|
|
+static int virt_concat_remove(struct platform_device *pdev)
|
|
+{
|
|
+ struct of_virt_concat *info;
|
|
+ int i;
|
|
+
|
|
+ info = platform_get_drvdata(pdev);
|
|
+ if (!info)
|
|
+ return 0;
|
|
+
|
|
+ // unset data for when this is called after a probe error
|
|
+ platform_set_drvdata(pdev, NULL);
|
|
+
|
|
+ if (info->cmtd) {
|
|
+ mtd_device_unregister(info->cmtd);
|
|
+ mtd_concat_destroy(info->cmtd);
|
|
+ }
|
|
+
|
|
+ if (info->devices) {
|
|
+ for (i = 0; i < info->num_devices; i++)
|
|
+ put_mtd_device(info->devices[i]);
|
|
+ }
|
|
+
|
|
+ return 0;
|
|
+}
|
|
+
|
|
+static int virt_concat_probe(struct platform_device *pdev)
|
|
+{
|
|
+ struct device_node *node = pdev->dev.of_node;
|
|
+ struct of_phandle_iterator it;
|
|
+ struct of_virt_concat *info;
|
|
+ struct mtd_info *mtd;
|
|
+ int err = 0, count;
|
|
+
|
|
+ count = of_count_phandle_with_args(node, "devices", NULL);
|
|
+ if (count <= 0)
|
|
+ return -EINVAL;
|
|
+
|
|
+ info = devm_kzalloc(&pdev->dev, sizeof(*info), GFP_KERNEL);
|
|
+ if (!info)
|
|
+ return -ENOMEM;
|
|
+ info->devices = devm_kcalloc(&pdev->dev, count,
|
|
+ sizeof(*(info->devices)), GFP_KERNEL);
|
|
+ if (!info->devices) {
|
|
+ err = -ENOMEM;
|
|
+ goto err_remove;
|
|
+ }
|
|
+
|
|
+ platform_set_drvdata(pdev, info);
|
|
+
|
|
+ of_for_each_phandle(&it, err, node, "devices", NULL, 0) {
|
|
+ mtd = get_mtd_device_by_node(it.node);
|
|
+ if (IS_ERR(mtd)) {
|
|
+ of_node_put(it.node);
|
|
+ err = -EPROBE_DEFER;
|
|
+ goto err_remove;
|
|
+ }
|
|
+
|
|
+ info->devices[info->num_devices++] = mtd;
|
|
+ }
|
|
+
|
|
+ info->cmtd = mtd_concat_create(info->devices, info->num_devices,
|
|
+ dev_name(&pdev->dev));
|
|
+ if (!info->cmtd) {
|
|
+ err = -ENXIO;
|
|
+ goto err_remove;
|
|
+ }
|
|
+
|
|
+ info->cmtd->dev.parent = &pdev->dev;
|
|
+ mtd_set_of_node(info->cmtd, node);
|
|
+ mtd_device_register(info->cmtd, NULL, 0);
|
|
+
|
|
+ return 0;
|
|
+
|
|
+err_remove:
|
|
+ virt_concat_remove(pdev);
|
|
+
|
|
+ return err;
|
|
+}
|
|
+
|
|
+static const struct of_device_id virt_concat_of_match[] = {
|
|
+ { .compatible = "mtd-concat", },
|
|
+ { /* sentinel */ }
|
|
+};
|
|
+MODULE_DEVICE_TABLE(of, virt_concat_of_match);
|
|
+
|
|
+static struct platform_driver virt_concat_driver = {
|
|
+ .probe = virt_concat_probe,
|
|
+ .remove = virt_concat_remove,
|
|
+ .driver = {
|
|
+ .name = "virt-mtdconcat",
|
|
+ .of_match_table = virt_concat_of_match,
|
|
+ },
|
|
+};
|
|
+
|
|
+module_platform_driver(virt_concat_driver);
|
|
+
|
|
+MODULE_LICENSE("GPL v2");
|
|
+MODULE_AUTHOR("Bernhard Frauendienst <kernel@nospam.obeliks.de>");
|
|
+MODULE_DESCRIPTION("Virtual concat MTD device driver");
|