soc: ti: add firmware file name as part of the driver

Currently firmware file name is included in the DTS. This is not scalable
as user has to change the DTS if they need upgrade to a new firmware.
Instead, add the firmware file name in the driver itself. As long as there
is no API change, new firmware upgrade is easy and require no driver
change. User is expected to copy the firmware image to the file system
and add a sym link to the new firmware for doing an upgrade. Driver add
a array of firmware file names to search for the available firmware blobs.
This scheme also prepare the driver for future changes to API if ever
happens. In such case it is assumed that driver needs to change to
accommodate the new firmware and new firmware file name will get added to
the array.

Also update the DT document to remove the firmware attribute and add
description about firmware in the driver documentation.

Signed-off-by: Murali Karicheri <m-karicheri2@ti.com>
Acked-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Santosh Shilimkar <ssantosh@kernel.org>

2 files changed, 28 insertions, 20 deletions

diff --git a/drivers/soc/ti/knav_qmss.h b/drivers/soc/ti/knav_qmss.h
index 51da2341280d..c31b8d826794 100644
--- a/drivers/soc/ti/knav_qmss.h
+++ b/drivers/soc/ti/knav_qmss.h
@@ -135,7 +135,6 @@ struct knav_pdsp_info {
 	};
 	void __iomem					*intd;
 	u32 __iomem					*iram;
-	const char					*firmware;
 	u32						id;
 	struct list_head				list;
 };
diff --git a/drivers/soc/ti/knav_qmss_queue.c b/drivers/soc/ti/knav_qmss_queue.c
index 6d8646db52cc..06d9de826758 100644
--- a/drivers/soc/ti/knav_qmss_queue.c
+++ b/drivers/soc/ti/knav_qmss_queue.c
@@ -68,6 +68,12 @@ static DEFINE_MUTEX(knav_dev_lock);
 	     idx < (kdev)->num_queues_in_use;			\
 	     idx++, inst = knav_queue_idx_to_inst(kdev, idx))
 
+/* All firmware file names end up here. List the firmware file names below.
+ * Newest followed by older ones. Search is done from start of the array
+ * until a firmware file is found.
+ */
+const char *knav_acc_firmwares[] = {"ks2_qmss_pdsp_acc48.bin"};
+
 /**
  * knav_queue_notify: qmss queue notfier call
  *
@@ -1439,7 +1445,6 @@ static int knav_queue_init_pdsps(struct knav_device *kdev,
 	struct device *dev = kdev->dev;
 	struct knav_pdsp_info *pdsp;
 	struct device_node *child;
-	int ret;
 
 	for_each_child_of_node(pdsps, child) {
 		pdsp = devm_kzalloc(dev, sizeof(*pdsp), GFP_KERNEL);
@@ -1448,17 +1453,6 @@ static int knav_queue_init_pdsps(struct knav_device *kdev,
 			return -ENOMEM;
 		}
 		pdsp->name = knav_queue_find_name(child);
-		ret = of_property_read_string(child, "firmware",
-					      &pdsp->firmware);
-		if (ret < 0 || !pdsp->firmware) {
-			dev_err(dev, "unknown firmware for pdsp %s\n",
-				pdsp->name);
-			devm_kfree(dev, pdsp);
-			continue;
-		}
-		dev_dbg(dev, "pdsp name %s fw name :%s\n", pdsp->name,
-			pdsp->firmware);
-
 		pdsp->iram =
 			knav_queue_map_reg(kdev, child,
 					   KNAV_QUEUE_PDSP_IRAM_REG_INDEX);
@@ -1489,9 +1483,9 @@ static int knav_queue_init_pdsps(struct knav_device *kdev,
 		}
 		of_property_read_u32(child, "id", &pdsp->id);
 		list_add_tail(&pdsp->list, &kdev->pdsps);
-		dev_dbg(dev, "added pdsp %s: command %p, iram %p, regs %p, intd %p, firmware %s\n",
+		dev_dbg(dev, "added pdsp %s: command %p, iram %p, regs %p, intd %p\n",
 			pdsp->name, pdsp->command, pdsp->iram, pdsp->regs,
-			pdsp->intd, pdsp->firmware);
+			pdsp->intd);
 	}
 	return 0;
 }
@@ -1518,14 +1512,29 @@ static int knav_queue_load_pdsp(struct knav_device *kdev,
 {
 	int i, ret, fwlen;
 	const struct firmware *fw;
+	bool found = false;
 	u32 *fwdata;
 
-	ret = request_firmware(&fw, pdsp->firmware, kdev->dev);
-	if (ret) {
-		dev_err(kdev->dev, "failed to get firmware %s for pdsp %s\n",
-			pdsp->firmware, pdsp->name);
-		return ret;
+	for (i = 0; i < ARRAY_SIZE(knav_acc_firmwares); i++) {
+		if (knav_acc_firmwares[i]) {
+			ret = request_firmware(&fw,
+					       knav_acc_firmwares[i],
+					       kdev->dev);
+			if (!ret) {
+				found = true;
+				break;
+			}
+		}
+	}
+
+	if (!found) {
+		dev_err(kdev->dev, "failed to get firmware for pdsp\n");
+		return -ENODEV;
 	}
+
+	dev_info(kdev->dev, "firmware file %s downloaded for PDSP\n",
+		 knav_acc_firmwares[i]);
+
 	writel_relaxed(pdsp->id + 1, pdsp->command + 0x18);
 	/* download the firmware */
 	fwdata = (u32 *)fw->data;