[PATCH v4 1/2] firmware_loader: introduce new API - request_firmware_direct_full_path()

Kweh, Hock Leong
2015-04-14T01:45:20Z

From: "Kweh, Hock Leong" <hock.leong.kweh@intel.com>

Introduce this new API for loading firmware from a specific location
instead of /lib/firmware/ by providing a full path to the firmware
file.

Cc: Ming Lei <ming.lei@canonical.com>
Cc: Matt Fleming <matt.fleming@intel.com>
Signed-off-by: Kweh, Hock Leong <hock.leong.kweh@intel.com>
---
drivers/base/firmware_class.c | 46 ++++++++++++++++++++++++++++++++++++-----
include/linux/firmware.h | 9 ++++++++
2 files changed, 50 insertions(+), 5 deletions(-)

diff --git a/drivers/base/firmware_class.c b/drivers/base/firmware_class.c
index 171841a..3ab7bb9 100644
--- a/drivers/base/firmware_class.c
+++ b/drivers/base/firmware_class.c
@@ -111,6 +111,7 @@ static inline long firmware_loading_timeout(void)
#define FW_OPT_FALLBACK 0
#endif
#define FW_OPT_NO_WARN (1U << 3)
+#define FW_OPT_FULL_PATH (1U << 4)

struct firmware_cache {
/* firmware_buf instance will be added into the below list */
@@ -318,20 +319,29 @@ fail:
}

static int fw_get_filesystem_firmware(struct device *device,
- struct firmware_buf *buf)
+ struct firmware_buf *buf,
+ unsigned int opt_flags)
{
int i;
int rc = -ENOENT;
char *path = __getname();
+ int path_array_size = 1;
+ static const char * const root_path[] = {"/"};
+ char **temp_path = (char **)root_path;

- for (i = 0; i < ARRAY_SIZE(fw_path); i++) {
+ if (!(opt_flags & FW_OPT_FULL_PATH)) {
+ temp_path = (char **)fw_path;
+ path_array_size = ARRAY_SIZE(fw_path);
+ }
+
+ for (i = 0; i < path_array_size; i++) {
struct file *file;

/* skip the unset customized path */
- if (!fw_path[i][0])
+ if (!temp_path[i][0])
continue;

- snprintf(path, PATH_MAX, "%s/%s", fw_path[i], buf->fw_id);
+ snprintf(path, PATH_MAX, "%s/%s", temp_path[i], buf->fw_id);

file = filp_open(path, O_RDONLY, 0);
if (IS_ERR(file))
@@ -1122,7 +1132,7 @@ _request_firmware(const struct firmware **firmware_p, const char *name,
}
}

- ret = fw_get_filesystem_firmware(device, fw->priv);
+ ret = fw_get_filesystem_firmware(device, fw->priv, opt_flags);
if (ret) {
if (!(opt_flags & FW_OPT_NO_WARN))
dev_warn(device,
@@ -1210,6 +1220,32 @@ int request_firmware_direct(const struct firmware **firmware_p,
EXPORT_SYMBOL_GPL(request_firmware_direct);

/**
+ * request_firmware_direct_full_path: - load firmware directly from exact
+ * full path
+ * @firmware_p: pointer to firmware image
+ * @name: full path to the firmware file with file name
+ * @device: device for which firmware is being loaded
+ *
+ * This function works like request_firmware_direct(), but this doesn't
+ * search the /lib/firmware/ for the firmware file. It support exact full
+ * path to the firmware file for loading.
+ **/
+int request_firmware_direct_full_path(const struct firmware **firmware_p,
+ const char *name, struct device *device)
+{
+ int ret;
+
+ __module_get(THIS_MODULE);
+ ret = _request_firmware(firmware_p, name, device,
+ FW_OPT_UEVENT | FW_OPT_NO_WARN |
+ FW_OPT_FULL_PATH);
+ module_put(THIS_MODULE);
+
+ return ret;
+}
+EXPORT_SYMBOL_GPL(request_firmware_direct_full_path);
+
+/**
* release_firmware: - release the resource associated with a firmware image
* @fw: firmware resource to release
**/
diff --git a/include/linux/firmware.h b/include/linux/firmware.h
index 5c41c5e..b7c6435 100644
--- a/include/linux/firmware.h
+++ b/include/linux/firmware.h
@@ -47,6 +47,8 @@ int request_firmware_nowait(
void (*cont)(const struct firmware *fw, void *context));
int request_firmware_direct(const struct firmware **fw, const char *name,
struct device *device);
+int request_firmware_direct_full_path(const struct firmware **fw,
+ const char *name, struct device *device);

void release_firmware(const struct firmware *fw);
#else
@@ -75,5 +77,12 @@ static inline int request_firmware_direct(const struct firmware **fw,
return -EINVAL;
}

+static inline int request_firmware_direct_full_path(const struct firmware **fw,
+ const char *name,
+ struct device *device)
+{
+ return -EINVAL;
+}
+
#endif
#endif
--
1.7.9.5