diff options
Diffstat (limited to 'nixos/modules/kernel-patches/0056-mtd-mtdconcat-add-dt-driver-for-concat-devices.patch')
| -rw-r--r-- | nixos/modules/kernel-patches/0056-mtd-mtdconcat-add-dt-driver-for-concat-devices.patch | 232 |
1 files changed, 232 insertions, 0 deletions
diff --git a/nixos/modules/kernel-patches/0056-mtd-mtdconcat-add-dt-driver-for-concat-devices.patch b/nixos/modules/kernel-patches/0056-mtd-mtdconcat-add-dt-driver-for-concat-devices.patch new file mode 100644 index 0000000..92f5603 --- /dev/null +++ b/nixos/modules/kernel-patches/0056-mtd-mtdconcat-add-dt-driver-for-concat-devices.patch @@ -0,0 +1,232 @@ +From 0a58b4681f061bf6a49c7102b08359c3ea19d84f 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 56/96] 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 + +diff --git a/drivers/mtd/Kconfig b/drivers/mtd/Kconfig +index f9ed93c4cf0f..7e4a3fa1dfd0 100644 +--- a/drivers/mtd/Kconfig ++++ b/drivers/mtd/Kconfig +@@ -241,4 +241,6 @@ source "drivers/mtd/ubi/Kconfig" + + source "drivers/mtd/hyperbus/Kconfig" + ++source "drivers/mtd/composite/Kconfig" ++ + endif # MTD +diff --git a/drivers/mtd/Makefile b/drivers/mtd/Makefile +index b14b7fe0f597..fbea3736b488 100644 +--- a/drivers/mtd/Makefile ++++ b/drivers/mtd/Makefile +@@ -33,3 +33,6 @@ obj-y += chips/ lpddr/ maps/ devices/ nand/ tests/ + obj-$(CONFIG_MTD_SPI_NOR) += spi-nor/ + obj-$(CONFIG_MTD_UBI) += ubi/ + obj-$(CONFIG_MTD_HYPERBUS) += hyperbus/ ++ ++# Composite drivers must be loaded last ++obj-y += composite/ +diff --git a/drivers/mtd/composite/Kconfig b/drivers/mtd/composite/Kconfig +new file mode 100644 +index 000000000000..0490fc0284bb +--- /dev/null ++++ b/drivers/mtd/composite/Kconfig +@@ -0,0 +1,12 @@ ++menu "Composite MTD device drivers" ++ depends on MTD!=n ++ ++config MTD_VIRT_CONCAT ++ tristate "Virtual concat MTD device" ++ help ++ This driver allows creation of a virtual MTD concat device, which ++ concatenates multiple underlying MTD devices to a single device. ++ This is required by some SoC boards where multiple memory banks are ++ used as one device with partitions spanning across device boundaries. ++ ++endmenu +diff --git a/drivers/mtd/composite/Makefile b/drivers/mtd/composite/Makefile +new file mode 100644 +index 000000000000..8421a0a30606 +--- /dev/null ++++ b/drivers/mtd/composite/Makefile +@@ -0,0 +1,6 @@ ++# SPDX-License-Identifier: GPL-2.0 ++# ++# linux/drivers/mtd/composite/Makefile ++# ++ ++obj-$(CONFIG_MTD_VIRT_CONCAT) += virt_concat.o +diff --git a/drivers/mtd/composite/virt_concat.c b/drivers/mtd/composite/virt_concat.c +new file mode 100644 +index 000000000000..bfd432188c35 +--- /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"); +-- +2.37.2 + |