[RFC 05/13] remoteproc: pru: Configure firmware based on client setup

[Puranjay Mohan <p-mohan@xxxxxx>]

From: Tero Kristo <t-kristo@xxxxxx>

Client device node property firmware-name is now used to configure
firmware for the PRU instances. The default firmware is also
restored once releasing the PRU resource.

Co-developed-by: Suman Anna <s-anna@xxxxxx>
Signed-off-by: Suman Anna <s-anna@xxxxxx>
Signed-off-by: Tero Kristo <t-kristo@xxxxxx>
Co-developed-by: Grzegorz Jaszczyk <grzegorz.jaszczyk@xxxxxxxxxx>
Signed-off-by: Grzegorz Jaszczyk <grzegorz.jaszczyk@xxxxxxxxxx>
Signed-off-by: Puranjay Mohan <p-mohan@xxxxxx>
---
 drivers/remoteproc/pru_rproc.c | 35 ++++++++++++++++++++++++++++++++++
 1 file changed, 35 insertions(+)

diff --git a/drivers/remoteproc/pru_rproc.c b/drivers/remoteproc/pru_rproc.c
index d06b763e995e..2977eb50631b 100644
--- a/drivers/remoteproc/pru_rproc.c
+++ b/drivers/remoteproc/pru_rproc.c
@@ -171,6 +171,23 @@ void pru_control_set_reg(struct pru_rproc *pru, unsigned int reg,
 	spin_unlock_irqrestore(&pru->rmw_lock, flags);
 }
 
+/**
+ * pru_rproc_set_firmware() - set firmware for a pru core
+ * @rproc: the rproc instance of the PRU
+ * @fw_name: the new firmware name, or NULL if default is desired
+ *
+ * Return: 0 on success, or errno in error case.
+ */
+static int pru_rproc_set_firmware(struct rproc *rproc, const char *fw_name)
+{
+	struct pru_rproc *pru = rproc->priv;
+
+	if (!fw_name)
+		fw_name = pru->fw_name;
+
+	return rproc_set_firmware(rproc, fw_name);
+}
+
 static struct rproc *__pru_rproc_get(struct device_node *np, int index)
 {
 	struct device_node *rproc_np = NULL;
@@ -231,6 +248,8 @@ struct rproc *pru_rproc_get(struct device_node *np, int index,
 	struct rproc *rproc;
 	struct pru_rproc *pru;
 	struct device *dev;
+	const char *fw_name;
+	int ret;
 
 	try_module_get(THIS_MODULE);
 
@@ -257,7 +276,21 @@ struct rproc *pru_rproc_get(struct device_node *np, int index,
 	if (pru_id)
 		*pru_id = pru->id;
 
+	ret = of_property_read_string_index(np, "firmware-name", index,
+					    &fw_name);
+	if (!ret) {
+		ret = pru_rproc_set_firmware(rproc, fw_name);
+		if (ret) {
+			dev_err(dev, "failed to set firmware: %d\n", ret);
+			goto err;
+		}
+	}
+
 	return rproc;
+
+err:
+	pru_rproc_put(rproc);
+	return ERR_PTR(ret);
 }
 EXPORT_SYMBOL_GPL(pru_rproc_get);
 
@@ -277,6 +310,8 @@ void pru_rproc_put(struct rproc *rproc)
 
 	pru = rproc->priv;
 
+	pru_rproc_set_firmware(rproc, NULL);
+
 	mutex_lock(&pru->lock);
 
 	if (!pru->client_np) {
-- 
2.17.1