From: Yi Li <yi1...@linux.intel.com>

Add function to load firmware in multiple chucks instead of

loading the whole big firmware file at once.

Signed-off-by: Yi Li <yi1...@linux.intel.com>
---
 drivers/base/firmware_class.c | 128 ++++++++++++++++++++++++++++++++++++++++++
 include/linux/firmware.h      |   2 +
 2 files changed, 130 insertions(+)

diff --git a/drivers/base/firmware_class.c b/drivers/base/firmware_class.c
index ac350c5..44fddff 100644
--- a/drivers/base/firmware_class.c
+++ b/drivers/base/firmware_class.c
@@ -436,6 +436,62 @@ fw_get_filesystem_firmware(struct device *device, struct 
firmware_buf *buf)
        return rc;
 }
 
+static int
+fw_stream_filesystem_firmware(struct device *device, struct firmware_buf *buf,
+                       size_t offset, size_t length)
+{
+       int i, len;
+       char *path;
+       int rc = 0;
+       struct file *file;
+
+       buf->size = 0;
+
+       path = __getname();
+       if (!path)
+               return -ENOMEM;
+
+       for (i = 0; i < ARRAY_SIZE(fw_path); i++) {
+               /* skip the unset customized path */
+               if (!fw_path[i][0])
+                       continue;
+
+               len = snprintf(path, PATH_MAX, "%s/%s",
+                              fw_path[i], buf->fw_id);
+               if (len >= PATH_MAX) {
+                       rc = -ENAMETOOLONG;
+                       break;
+               }
+
+               if (!path || !*path)
+                       continue;
+
+               if (!buf->data) {
+                       buf->data = vmalloc(length);
+                       if (!buf->data) {
+                               rc = -ENOMEM;
+                               break;
+                       }
+               }
+
+               file = filp_open(path, O_RDONLY, 0);
+               if (IS_ERR(file))
+                       continue;
+
+               buf->size = kernel_read(file, offset, (char *) buf->data,
+                                       length);
+               fput(file);
+               break;
+       }
+
+       __putname(path);
+
+       if (rc)
+               dev_err(device, "loading %s failed with error %d\n",
+                        path, rc);
+       return rc;
+}
+
 /* firmware holds the ownership of pages */
 static void firmware_free_data(const struct firmware *fw)
 {
@@ -1267,6 +1323,78 @@ request_firmware(const struct firmware **firmware_p, 
const char *name,
 }
 EXPORT_SYMBOL(request_firmware);
 
+static int
+_stream_firmware(const struct firmware **firmware_p, const char *name,
+                 struct device *device, void *buf, size_t size,
+                 unsigned int opt_flags, size_t offset, size_t length)
+{
+       int ret;
+       struct firmware *fw = NULL;
+       struct firmware_buf *fbuf;
+
+       if ((!firmware_p) || (!name || name[0] == '\0')) {
+               dev_err(device, "invalid firmware pointer or file name\n");
+               return -EINVAL;
+       }
+
+       if (!*firmware_p) {
+               ret = _request_firmware_prepare(&fw, name, device, buf, size);
+               if (ret <= 0) {
+                       dev_err(device, "%s: _request_firmware_prepare failed 
%d\n",
+                               __func__, ret);
+               }
+       } else {
+               fw = (struct firmware *) *firmware_p;
+       }
+
+       fbuf = (struct firmware_buf *) fw->priv;
+       ret = fw_stream_filesystem_firmware(device, fbuf, offset, length);
+       fw->size = fbuf->size;
+       fw->data = fbuf->data;
+       *firmware_p = fw;
+
+       if (ret)
+               dev_err(device, "streaming with error %d\n", ret);
+       return ret;
+}
+
+/**
+ * stream_firmware: - send firmware request and wait for it
+ * @firmware_p: pointer to firmware image
+ * @name: name of firmware file
+ * @device: device for which firmware is being loaded
+ * @offset: offset of the file to read from
+ * @length: length in bytes to read
+ *
+ *      @firmware_p will be used to return a firmware image by the name
+ *      of @name for device @device.
+ *
+ *      Should be called from user context where sleeping is allowed.
+ *
+ *      @name will be used as $FIRMWARE in the uevent environment and
+ *      should be distinctive enough not to be confused with any other
+ *      firmware image for this or any other device.
+ *
+ *     Caller must hold the reference count of @device.
+ *
+ *     The function can be called safely inside device's suspend and
+ *     resume callback.
+ **/
+int
+stream_firmware(const struct firmware **firmware_p, const char *name,
+                struct device *device, size_t offset, size_t length)
+{
+       size_t ret;
+
+       /* Need to pin this module until return */
+       __module_get(THIS_MODULE);
+       ret = _stream_firmware(firmware_p, name, device, NULL, 0,
+                               FW_OPT_UEVENT | FW_OPT_NO_WARN, offset, length);
+       module_put(THIS_MODULE);
+       return ret;
+}
+EXPORT_SYMBOL(stream_firmware);
+
 /**
  * request_firmware_direct: - load firmware directly without usermode helper
  * @firmware_p: pointer to firmware image
diff --git a/include/linux/firmware.h b/include/linux/firmware.h
index b1f9f0c..accd7f6 100644
--- a/include/linux/firmware.h
+++ b/include/linux/firmware.h
@@ -41,6 +41,8 @@ struct builtin_fw {
 #if defined(CONFIG_FW_LOADER) || (defined(CONFIG_FW_LOADER_MODULE) && 
defined(MODULE))
 int request_firmware(const struct firmware **fw, const char *name,
                     struct device *device);
+int stream_firmware(const struct firmware **fw, const char *name,
+                   struct device *device, size_t offset, size_t length);
 int request_firmware_nowait(
        struct module *module, bool uevent,
        const char *name, struct device *device, gfp_t gfp, void *context,
-- 
2.7.4

Reply via email to