[PATCH 2/2] file-list: support special 'auto', 'block', 'nvmem' specifiers
Ahmad Fatoum
a.fatoum at pengutronix.de
Thu Jun 8 00:24:18 PDT 2023
Best practice is for each board to populate $global.system.partitions
or $global.fastboot.partitions with a string exporting its flashable
devices in a descriptive manner, e.g. "/dev/mmc0(eMMC),/dev/mmc1(SD)".
This often goes into BSPs though, so upstream boards are left without
default partitions, making use a bit cumbersome. Make this easier
by providing three new magic specifiers:
- nvmem: exports all registered NVMEM devices (e.g. EEPROMs, Fuse banks)
- block: exports all registered block devices (e.g. eMMC and SD)
- auto: currently equivalent to "nvmem,block". May be extended
to raw MTD and UBI in future
This makes it easy to export devices on any board:
usbgadget -A auto -b
or
usbgadget -S auto,/tmp/fitimage(fitimage)c
Signed-off-by: Ahmad Fatoum <a.fatoum at pengutronix.de>
---
Documentation/user/usb.rst | 17 +++++++++++++++++
common/block.c | 16 ++++++++++++++++
common/file-list.c | 29 +++++++++++++++++++++++++++--
drivers/nvmem/core.c | 16 ++++++++++++++++
include/block.h | 6 ++++++
include/linux/nvmem-consumer.h | 8 ++++++++
6 files changed, 90 insertions(+), 2 deletions(-)
diff --git a/Documentation/user/usb.rst b/Documentation/user/usb.rst
index f2f57ead98d4..6fed0f619b32 100644
--- a/Documentation/user/usb.rst
+++ b/Documentation/user/usb.rst
@@ -73,6 +73,23 @@ Example:
/dev/nand0.barebox.bb(barebox)sr,/kernel(kernel)rc
+Board code authors are encouraged to provide a default environment containing
+partitions with descriptive names. For boards where this is not specified,
+there exist a number of **partition** specifiers for automatically generating entries:
+
+* ``nvmem`` exports all registered NVMEM devices (e.g. EEPROMs, Fuse banks)
+* ``block`` exports all registered block devices (e.g. eMMC and SD)
+* ``auto`` currently equivalent to ``nvmem,block``. May be extended to other flashable
+ devices, like MTD or UBI volumes in future
+
+Example usage of exporting registered block devices, barebox update
+handlers and a single file that is created on flashing:
+
+.. code-block:: sh
+
+ detect -a # optional. Detects everything, so auto can register it
+ usbgadget -A auto,/tmp/fitimage(fitimage)c -b
+
DFU
^^^
diff --git a/common/block.c b/common/block.c
index f6eeb7f9c85f..3a4a9fb73149 100644
--- a/common/block.c
+++ b/common/block.c
@@ -11,6 +11,7 @@
#include <linux/err.h>
#include <linux/list.h>
#include <dma.h>
+#include <file-list.h>
#define BLOCKSIZE(blk) (1 << blk->blockbits)
@@ -458,3 +459,18 @@ int block_write(struct block_device *blk, void *buf, sector_t block, blkcnt_t nu
return ret < 0 ? ret : 0;
}
+
+unsigned file_list_add_blockdevs(struct file_list *files)
+{
+ struct block_device *blk;
+ unsigned count = 0;
+ int err;
+
+ list_for_each_entry(blk, &block_device_list, list) {
+ err = file_list_add_cdev_entry(files, &blk->cdev, 0);
+ if (!err)
+ count++;
+ }
+
+ return count;
+}
diff --git a/common/file-list.c b/common/file-list.c
index 5c7020111145..80ab108753e0 100644
--- a/common/file-list.c
+++ b/common/file-list.c
@@ -9,6 +9,8 @@
#include <stringlist.h>
#include <linux/err.h>
#include <driver.h>
+#include <block.h>
+#include <linux/nvmem-consumer.h>
#define PARSE_DEVICE 0
#define PARSE_NAME 1
@@ -59,12 +61,32 @@ int file_list_add_cdev_entry(struct file_list *files, struct cdev *cdev,
xasprintf("/dev/%s", cdev->name), flags);
}
+static bool file_list_handle_spec(struct file_list *files, const char *spec)
+{
+ unsigned count = 0;
+
+ if (!strcmp(spec, "auto")) {
+ count += file_list_add_blockdevs(files);
+ count += file_list_add_nvmemdevs(files);
+ } else if (!strcmp(spec, "block")) {
+ count += file_list_add_blockdevs(files);
+ } else if (!strcmp(spec, "nvmem")) {
+ count += file_list_add_nvmemdevs(files);
+ } else {
+ return false;
+ }
+
+ pr_debug("'%s' spcifier resulted in %u entries\n", spec, count);
+ return true;
+}
+
static int file_list_parse_one(struct file_list *files, const char *partstr, const char **endstr)
{
int i = 0, state = PARSE_DEVICE;
char filename[PATH_MAX];
char name[PATH_MAX];
unsigned long flags = 0;
+ bool special = false;
memset(filename, 0, sizeof(filename));
memset(name, 0, sizeof(name));
@@ -115,7 +137,10 @@ static int file_list_parse_one(struct file_list *files, const char *partstr, con
partstr++;
}
- if (state != PARSE_FLAGS) {
+ if (state == PARSE_DEVICE)
+ special = file_list_handle_spec(files, filename);
+
+ if (!special && state != PARSE_FLAGS) {
pr_err("Missing ')'\n");
return -EINVAL;
}
@@ -124,7 +149,7 @@ static int file_list_parse_one(struct file_list *files, const char *partstr, con
partstr++;
*endstr = partstr;
- return file_list_add_entry(files, name, filename, flags);
+ return special ? 0 : file_list_add_entry(files, name, filename, flags);
}
static const char *flags_to_str(int flags)
diff --git a/drivers/nvmem/core.c b/drivers/nvmem/core.c
index e0110296f87b..6e5fb6f4f5a5 100644
--- a/drivers/nvmem/core.c
+++ b/drivers/nvmem/core.c
@@ -12,6 +12,7 @@
#include <of.h>
#include <linux/nvmem-consumer.h>
#include <linux/nvmem-provider.h>
+#include <file-list.h>
struct nvmem_device {
const char *name;
@@ -52,6 +53,21 @@ void nvmem_devices_print(void)
}
}
+unsigned file_list_add_nvmemdevs(struct file_list *files)
+{
+ struct nvmem_device *dev;
+ unsigned count = 0;
+ int err;
+
+ list_for_each_entry(dev, &nvmem_devs, node) {
+ err = file_list_add_cdev_entry(files, &dev->cdev, 0);
+ if (!err)
+ count++;
+ }
+
+ return count;
+}
+
static ssize_t nvmem_cdev_read(struct cdev *cdev, void *buf, size_t count,
loff_t offset, unsigned long flags)
{
diff --git a/include/block.h b/include/block.h
index da258f509b41..44037bd74c61 100644
--- a/include/block.h
+++ b/include/block.h
@@ -7,6 +7,7 @@
#include <linux/types.h>
struct block_device;
+struct file_list;
struct block_device_ops {
int (*read)(struct block_device *, void *buf, sector_t block, blkcnt_t num_blocks);
@@ -51,11 +52,16 @@ static inline int block_flush(struct block_device *blk)
#ifdef CONFIG_BLOCK
struct block_device *cdev_get_block_device(const struct cdev *cdev);
+unsigned file_list_add_blockdevs(struct file_list *files);
#else
static inline struct block_device *cdev_get_block_device(const struct cdev *cdev)
{
return NULL;
}
+static inline unsigned file_list_add_blockdevs(struct file_list *files)
+{
+ return 0;
+}
#endif
static inline bool cdev_is_block_device(const struct cdev *cdev)
diff --git a/include/linux/nvmem-consumer.h b/include/linux/nvmem-consumer.h
index 397c4c29dafd..f215851b3936 100644
--- a/include/linux/nvmem-consumer.h
+++ b/include/linux/nvmem-consumer.h
@@ -17,6 +17,7 @@ struct device_node;
/* consumer cookie */
struct nvmem_cell;
struct nvmem_device;
+struct file_list;
struct nvmem_cell_info {
const char *name;
@@ -53,6 +54,8 @@ int nvmem_device_cell_write(struct nvmem_device *nvmem,
void nvmem_devices_print(void);
+unsigned file_list_add_nvmemdevs(struct file_list *files);
+
#else
static inline struct nvmem_cell *nvmem_cell_get(struct device *dev,
@@ -128,6 +131,11 @@ static inline int nvmem_device_write(struct nvmem_device *nvmem,
return -EOPNOTSUPP;
}
+static inline unsigned file_list_add_nvmemdevs(struct file_list *files)
+{
+ return 0;
+}
+
#endif /* CONFIG_NVMEM */
#if IS_ENABLED(CONFIG_NVMEM) && IS_ENABLED(CONFIG_OFTREE)
--
2.39.2
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