fastboot/dfu: use system partitions as fall back

Use the new system partitions infrastructure to have fastboot and DFU
fall back to using the same partitions if the global.usbgadget.dfu_function
and global.fastboot_partitions are not set, respectively.

No functional change intended for configurations that have
SYSTEM_PARTITIONS disabled.

Signed-off-by: Ahmad Fatoum <a.fatoum@pengutronix.de>
Link: https://lore.barebox.org/20210503114901.13095-13-a.fatoum@pengutronix.de
Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de>

7 files changed, 77 insertions, 37 deletions

diff --git a/common/fastboot.c b/common/fastboot.c
index c8576a8d97..dc80b66e67 100644
--- a/common/fastboot.c
+++ b/common/fastboot.c
@@ -41,6 +41,7 @@
 #include <linux/stat.h>
 #include <linux/mtd/mtd.h>
 #include <fastboot.h>
+#include <system-partitions.h>
 
 #define FASTBOOT_VERSION		"0.4"
 
@@ -932,9 +933,13 @@ bool get_fastboot_bbu(void)
 	return fastboot_bbu;
 }
 
-const char *get_fastboot_partitions(void)
+struct file_list *get_fastboot_partitions(void)
 {
-	return fastboot_partitions;
+	if (fastboot_partitions && *fastboot_partitions)
+		return file_list_parse(fastboot_partitions);
+	if (!system_partitions_empty())
+		return system_partitions_get();
+	return NULL;
 }
 
 static int fastboot_globalvars_init(void)
diff --git a/common/usbgadget.c b/common/usbgadget.c
index 009debd93e..d4437b5169 100644
--- a/common/usbgadget.c
+++ b/common/usbgadget.c
@@ -17,6 +17,7 @@
 #include <usb/gadget-multi.h>
 #include <globalvar.h>
 #include <magicvar.h>
+#include <system-partitions.h>
 
 static int autostart;
 static int acm;
@@ -24,14 +25,29 @@ static char *dfu_function;
 
 static struct file_list *parse(const char *files)
 {
-	struct file_list *list = file_list_parse(files);
+	struct file_list *list;
+
+	if (!files)
+		return NULL;
+
+	list = file_list_parse(files);
 	if (IS_ERR(list)) {
 		pr_err("Parsing file list \"%s\" failed: %pe\n", files, list);
 		return NULL;
 	}
+
 	return list;
 }
 
+static inline struct file_list *get_dfu_function(void)
+{
+	if (dfu_function && *dfu_function)
+		return file_list_parse(dfu_function);
+	if (!system_partitions_empty())
+		return system_partitions_get();
+	return NULL;
+}
+
 int usbgadget_register(bool dfu, const char *dfu_opts,
 		       bool fastboot, const char *fastboot_opts,
 		       bool acm, bool export_bbu)
@@ -39,45 +55,44 @@ int usbgadget_register(bool dfu, const char *dfu_opts,
 	int ret;
 	struct device_d *dev;
 	struct f_multi_opts *opts;
-	const char *fastboot_partitions = get_fastboot_partitions();
-
-	if (dfu && !dfu_opts && dfu_function && *dfu_function)
-		dfu_opts = dfu_function;
-
-	if (IS_ENABLED(CONFIG_FASTBOOT_BASE) && fastboot && !fastboot_opts &&
-	    fastboot_partitions && *fastboot_partitions)
-		fastboot_opts = fastboot_partitions;
-
-	if (!dfu_opts && !fastboot_opts && !acm)
-		return COMMAND_ERROR_USAGE;
-
-	/*
-	 * Creating a gadget with both DFU and Fastboot may not work.
-	 * fastboot 1:8.1.0+r23-5 can deal with it, but dfu-util 0.9
-	 * seems to assume that the device only has a single configuration
-	 * That's not our fault though. Emit a warning and continue
-	 */
-	if (fastboot_opts && dfu_opts)
-		pr_warn("Both DFU and Fastboot enabled. dfu-util may not like this!\n");
 
 	opts = xzalloc(sizeof(*opts));
 	opts->release = usb_multi_opts_release;
 
-	if (fastboot_opts) {
+	if (dfu) {
+		opts->dfu_opts.files = parse(dfu_opts);
+		if (IS_ENABLED(CONFIG_USB_GADGET_DFU) && file_list_empty(opts->dfu_opts.files)) {
+			file_list_free(opts->dfu_opts.files);
+			opts->dfu_opts.files = get_dfu_function();
+		}
+	}
+
+	if (fastboot) {
 		opts->fastboot_opts.files = parse(fastboot_opts);
+		if (IS_ENABLED(CONFIG_FASTBOOT_BASE) && file_list_empty(opts->fastboot_opts.files)) {
+			file_list_free(opts->fastboot_opts.files);
+			opts->fastboot_opts.files = get_fastboot_partitions();
+		}
+
 		opts->fastboot_opts.export_bbu = export_bbu;
 	}
 
-	if (dfu_opts)
-		opts->dfu_opts.files = parse(dfu_opts);
+	opts->create_acm = acm;
 
-	if (!opts->dfu_opts.files && !opts->fastboot_opts.files && !acm) {
+	if (usb_multi_count_functions(opts) == 0) {
 		pr_warn("No functions to register\n");
-		free(opts);
-		return 0;
+		ret = COMMAND_ERROR_USAGE;
+		goto err;
 	}
 
-	opts->create_acm = acm;
+	/*
+	 * Creating a gadget with both DFU and Fastboot may not work.
+	 * fastboot 1:8.1.0+r23-5 can deal with it, but dfu-util 0.9
+	 * seems to assume that the device only has a single configuration
+	 * That's not our fault though. Emit a warning and continue
+	 */
+	if (!file_list_empty(opts->fastboot_opts.files) && !file_list_empty(opts->dfu_opts.files))
+		pr_warn("Both DFU and Fastboot enabled. dfu-util may not like this!\n");
 
 	dev = get_device_by_name("otg");
 	if (dev)
@@ -85,7 +100,11 @@ int usbgadget_register(bool dfu, const char *dfu_opts,
 
 	ret = usb_multi_register(opts);
 	if (ret)
-		usb_multi_opts_release(opts);
+		goto err;
+
+	return 0;
+err:
+	usb_multi_opts_release(opts);
 
 	return ret;
 }
diff --git a/drivers/usb/gadget/multi.c b/drivers/usb/gadget/multi.c
index da4a759117..144ac0624b 100644
--- a/drivers/usb/gadget/multi.c
+++ b/drivers/usb/gadget/multi.c
@@ -266,6 +266,18 @@ void usb_multi_unregister(void)
 	gadget_multi_opts = NULL;
 }
 
+unsigned usb_multi_count_functions(struct f_multi_opts *opts)
+{
+	unsigned count = 0;
+
+	count += !file_list_empty(opts->fastboot_opts.files) ||
+		opts->fastboot_opts.export_bbu;
+	count += !file_list_empty(opts->dfu_opts.files);
+	count += opts->create_acm;
+
+	return count;
+}
+
 void usb_multi_opts_release(struct f_multi_opts *opts)
 {
 	file_list_free(opts->fastboot_opts.files);
diff --git a/include/fastboot.h b/include/fastboot.h
index 2eab2dfe6a..cf8a177bf1 100644
--- a/include/fastboot.h
+++ b/include/fastboot.h
@@ -58,16 +58,16 @@ enum fastboot_msg_type {
 
 #ifdef CONFIG_FASTBOOT_BASE
 bool get_fastboot_bbu(void);
-const char *get_fastboot_partitions(void);
+struct file_list *get_fastboot_partitions(void);
 #else
 static inline int get_fastboot_bbu(void)
 {
 	return false;
 }
 
-static inline const char *get_fastboot_partitions(void)
+static inline struct file_list *get_fastboot_partitions(void)
 {
-	return NULL;
+	return file_list_parse("");
 }
 #endif
 
diff --git a/include/file-list.h b/include/file-list.h
index 2538883c36..be97a49b7a 100644
--- a/include/file-list.h
+++ b/include/file-list.h
@@ -35,4 +35,9 @@ struct file_list_entry *file_list_entry_by_name(struct file_list *files, const c
 #define file_list_for_each_entry(files, entry) \
 	list_for_each_entry(entry, &files->list, list)
 
+static inline bool file_list_empty(struct file_list *files)
+{
+	return !files || !files->num_entries;
+}
+
 #endif /* __FILE_LIST */
diff --git a/include/usb/gadget-multi.h b/include/usb/gadget-multi.h
index 9bb6c889f3..f30dae5686 100644
--- a/include/usb/gadget-multi.h
+++ b/include/usb/gadget-multi.h
@@ -15,6 +15,7 @@ struct f_multi_opts {
 int usb_multi_register(struct f_multi_opts *opts);
 void usb_multi_unregister(void);
 void usb_multi_opts_release(struct f_multi_opts *opts);
+unsigned usb_multi_count_functions(struct f_multi_opts *opts);
 
 int usbgadget_register(bool dfu, const char *dfu_opts,
 		       bool fastboot, const char *fastboot_opts,
diff --git a/net/fastboot.c b/net/fastboot.c
index 9082aa48f6..df388adc89 100644
--- a/net/fastboot.c
+++ b/net/fastboot.c
@@ -499,7 +499,6 @@ void fastboot_net_free(struct fastboot_net *fbn)
 struct fastboot_net *fastboot_net_init(struct fastboot_opts *opts)
 {
 	struct fastboot_net *fbn;
-	const char *partitions = get_fastboot_partitions();
 	bool bbu = get_fastboot_bbu();
 	int ret;
 
@@ -513,8 +512,7 @@ struct fastboot_net *fastboot_net_init(struct fastboot_opts *opts)
 		fbn->fastboot.cmd_flash = opts->cmd_flash;
 		ret = fastboot_generic_init(&fbn->fastboot, opts->export_bbu);
 	} else {
-		fbn->fastboot.files = file_list_parse(partitions ?
-						      partitions : "");
+		fbn->fastboot.files = get_fastboot_partitions() ?: file_list_parse("");
 		ret = fastboot_generic_init(&fbn->fastboot, bbu);
 	}
 	if (ret)