ath10k: search DT for qcom,ath10k-calibration-variant

Board Data File (BDF) is loaded upon driver boot-up procedure. The right
board data file is identified on QCA4019 using bus, bmi-chip-id and
bmi-board-id.

The problem, however, can occur when the (default) board data file cannot
fulfill with the vendor requirements and it is necessary to use a different
board data file.

This problem was solved for SMBIOS by adding a special SMBIOS type 0xF8.
Something similar has to be provided for systems without SMBIOS but with
device trees. No solution was specified by QCA and therefore a new one has
to be found for ath10k.

The device tree requires addition strings to define the variant name

    wifi@a000000 {
    	status = "okay";
    	qcom,ath10k-calibration-variant = "RT-AC58U";
    };

    wifi@a800000 {
    	status = "okay";
    	qcom,ath10k-calibration-variant = "RT-AC58U";
    };

This would create the boarddata identifiers for the board-2.bin search

 *  bus=ahb,bmi-chip-id=0,bmi-board-id=16,variant=RT-AC58U
 *  bus=ahb,bmi-chip-id=0,bmi-board-id=17,variant=RT-AC58U

Signed-off-by: Sven Eckelmann <sven.eckelmann@openmesh.com>
Signed-off-by: Kalle Valo <kvalo@qca.qualcomm.com>

1 files changed, 33 insertions, 7 deletions

diff --git a/drivers/net/wireless/ath/ath10k/core.c b/drivers/net/wireless/ath/ath10k/core.c
index b29fdbd21ead..6264e2cc4c0d 100644
--- a/drivers/net/wireless/ath/ath10k/core.c
+++ b/drivers/net/wireless/ath/ath10k/core.c
@@ -860,6 +860,28 @@ static int ath10k_core_check_smbios(struct ath10k *ar)
         return 0;
 }
 
+static int ath10k_core_check_dt(struct ath10k *ar)
+{
+        struct device_node *node;
+        const char *variant = NULL;
+
+        node = ar->dev->of_node;
+        if (!node)
+                return -ENOENT;
+
+        of_property_read_string(node, "qcom,ath10k-calibration-variant",
+                                &variant);
+        if (!variant)
+                return -ENODATA;
+
+        if (strscpy(ar->id.bdf_ext, variant, sizeof(ar->id.bdf_ext)) < 0)
+                ath10k_dbg(ar, ATH10K_DBG_BOOT,
+                           "bdf variant string is longer than the buffer can accommodate (variant: %s)\n",
+                            variant);
+
+        return 0;
+}
+
 static int ath10k_download_and_run_otp(struct ath10k *ar)
 {
         u32 result, address = ar->hw_params.patch_load_addr;
@@ -1231,19 +1253,19 @@ static int ath10k_core_create_board_name(struct ath10k *ar, char *name,
         /* strlen(',variant=') + strlen(ar->id.bdf_ext) */
         char variant[9 + ATH10K_SMBIOS_BDF_EXT_STR_LENGTH] = { 0 };
 
+        if (ar->id.bdf_ext[0] != '\0')
+                scnprintf(variant, sizeof(variant), ",variant=%s",
+                          ar->id.bdf_ext);
+
         if (ar->id.bmi_ids_valid) {
                 scnprintf(name, name_len,
-                          "bus=%s,bmi-chip-id=%d,bmi-board-id=%d",
+                          "bus=%s,bmi-chip-id=%d,bmi-board-id=%d%s",
                           ath10k_bus_str(ar->hif.bus),
                           ar->id.bmi_chip_id,
-                          ar->id.bmi_board_id);
+                          ar->id.bmi_board_id, variant);
                 goto out;
         }
 
-        if (ar->id.bdf_ext[0] != '\0')
-                scnprintf(variant, sizeof(variant), ",variant=%s",
-                          ar->id.bdf_ext);
-
         scnprintf(name, name_len,
                   "bus=%s,vendor=%04x,device=%04x,subsystem-vendor=%04x,subsystem-device=%04x%s",
                   ath10k_bus_str(ar->hif.bus),
@@ -2343,7 +2365,11 @@ static int ath10k_core_probe_fw(struct ath10k *ar)
 
         ret = ath10k_core_check_smbios(ar);
         if (ret)
-                ath10k_dbg(ar, ATH10K_DBG_BOOT, "bdf variant name not set.\n");
+                ath10k_dbg(ar, ATH10K_DBG_BOOT, "SMBIOS bdf variant name not set.\n");
+
+        ret = ath10k_core_check_dt(ar);
+        if (ret)
+                ath10k_dbg(ar, ATH10K_DBG_BOOT, "DT bdf variant name not set.\n");
 
         ret = ath10k_core_fetch_board_file(ar);
         if (ret) {