ath6kl: query device tree for firmware board-id

When no default board data file is present query the device tree for a
board-id setting to identify the board data to use.  If the FDT lacks the
necesary info fall back to the previous behaviour of using a compile-time
board filename.

Signed-off-by: Sam Leffler <sleffler@chromium.org>
Signed-off-by: Kalle Valo <kvalo@qca.qualcomm.com>

1 files changed, 64 insertions, 0 deletions

diff --git a/drivers/net/wireless/ath/ath6kl/init.c b/drivers/net/wireless/ath/ath6kl/init.c
index eca34aa6e4ba..91716709cac8 100644
--- a/drivers/net/wireless/ath/ath6kl/init.c
+++ b/drivers/net/wireless/ath/ath6kl/init.c
@@ -15,6 +15,7 @@
  * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
  */
 
+#include <linux/of.h>
 #include <linux/mmc/sdio_func.h>
 #include "core.h"
 #include "cfg80211.h"
@@ -680,6 +681,64 @@ static int ath6kl_get_fw(struct ath6kl *ar, const char *filename,
         return ret;
 }
 
+#ifdef CONFIG_OF
+static const char *get_target_ver_dir(const struct ath6kl *ar)
+{
+        switch (ar->version.target_ver) {
+        case AR6003_REV1_VERSION:
+                return "ath6k/AR6003/hw1.0";
+        case AR6003_REV2_VERSION:
+                return "ath6k/AR6003/hw2.0";
+        case AR6003_REV3_VERSION:
+                return "ath6k/AR6003/hw2.1.1";
+        }
+        ath6kl_warn("%s: unsupported target version 0x%x.\n", __func__,
+                    ar->version.target_ver);
+        return NULL;
+}
+
+/*
+ * Check the device tree for a board-id and use it to construct
+ * the pathname to the firmware file.  Used (for now) to find a
+ * fallback to the "bdata.bin" file--typically a symlink to the
+ * appropriate board-specific file.
+ */
+static bool check_device_tree(struct ath6kl *ar)
+{
+        static const char *board_id_prop = "atheros,board-id";
+        struct device_node *node;
+        char board_filename[64];
+        const char *board_id;
+        int ret;
+
+        for_each_compatible_node(node, NULL, "atheros,ath6kl") {
+                board_id = of_get_property(node, board_id_prop, NULL);
+                if (board_id == NULL) {
+                        ath6kl_warn("No \"%s\" property on %s node.\n",
+                                    board_id_prop, node->name);
+                        continue;
+                }
+                snprintf(board_filename, sizeof(board_filename),
+                         "%s/bdata.%s.bin", get_target_ver_dir(ar), board_id);
+
+                ret = ath6kl_get_fw(ar, board_filename, &ar->fw_board,
+                                    &ar->fw_board_len);
+                if (ret) {
+                        ath6kl_err("Failed to get DT board file %s: %d\n",
+                                   board_filename, ret);
+                        continue;
+                }
+                return true;
+        }
+        return false;
+}
+#else
+static bool check_device_tree(struct ath6kl *ar)
+{
+        return false;
+}
+#endif /* CONFIG_OF */
+
 static int ath6kl_fetch_board_file(struct ath6kl *ar)
 {
         const char *filename;
@@ -704,6 +763,11 @@ static int ath6kl_fetch_board_file(struct ath6kl *ar)
                 return 0;
         }
 
+        if (check_device_tree(ar)) {
+                /* got board file from device tree */
+                return 0;
+        }
+
         /* there was no proper board file, try to use default instead */
         ath6kl_warn("Failed to get board file %s (%d), trying to find default board file.\n",
                     filename, ret);