ASoC: qcom: Constify GPR packet being send over GPR interface

gpr_send_pkt() and pkt_router_send_svc_pkt() only send the GPR packet
they receive, without any need to actually modify it, so mark the
pointer to GPR packet as pointer to const for code safety and code
self-documentation.  Several users of this interface can follow up and
also operate on pointer to const.

Acked-by: Mathieu Poirier <mathieu.poirier@linaro.org>
Acked-by: Mark Brown <broonie@kernel.org>
Signed-off-by: Krzysztof Kozlowski <krzysztof.kozlowski@oss.qualcomm.com>
Link: https://lore.kernel.org/r/20260317-rpmsg-send-const-v3-4-4d7fd27f037f@oss.qualcomm.com
Signed-off-by: Bjorn Andersson <andersson@kernel.org>

Author: krzk

drivers/soc/qcom/apr.c

@@ -123,10 +123,10 @@ gpr_port_t *gpr_alloc_port(struct apr_device *gdev, struct device *dev,
 }
 EXPORT_SYMBOL_GPL(gpr_alloc_port);
 
-static int pkt_router_send_svc_pkt(struct pkt_router_svc *svc, struct gpr_pkt *pkt)
+static int pkt_router_send_svc_pkt(struct pkt_router_svc *svc, const struct gpr_pkt *pkt)
 {
 	struct packet_router *pr = svc->pr;
-	struct gpr_hdr *hdr;
+	const struct gpr_hdr *hdr;
 	unsigned long flags;
 	int ret;
 
@@ -139,13 +139,13 @@ static int pkt_router_send_svc_pkt(struct pkt_router_svc *svc, struct gpr_pkt *p
 	return ret ? ret : hdr->pkt_size;
 }
 
-int gpr_send_pkt(struct apr_device *gdev, struct gpr_pkt *pkt)
+int gpr_send_pkt(struct apr_device *gdev, const struct gpr_pkt *pkt)
 {
 	return pkt_router_send_svc_pkt(&gdev->svc, pkt);
 }
 EXPORT_SYMBOL_GPL(gpr_send_pkt);
 
-int gpr_send_port_pkt(gpr_port_t *port, struct gpr_pkt *pkt)
+int gpr_send_port_pkt(gpr_port_t *port, const struct gpr_pkt *pkt)
 {
 	return pkt_router_send_svc_pkt(port, pkt);
 }

include/linux/soc/qcom/apr.h

@@ -191,7 +191,7 @@ int apr_send_pkt(struct apr_device *adev, struct apr_pkt *pkt);
 gpr_port_t *gpr_alloc_port(gpr_device_t *gdev, struct device *dev,
 				gpr_port_cb cb, void *priv);
 void gpr_free_port(gpr_port_t *port);
-int gpr_send_port_pkt(gpr_port_t *port, struct gpr_pkt *pkt);
-int gpr_send_pkt(gpr_device_t *gdev, struct gpr_pkt *pkt);
+int gpr_send_port_pkt(gpr_port_t *port, const struct gpr_pkt *pkt);
+int gpr_send_pkt(gpr_device_t *gdev, const struct gpr_pkt *pkt);
 
 #endif /* __QCOM_APR_H_ */

sound/soc/qcom/qdsp6/audioreach.c

@@ -579,10 +579,10 @@ EXPORT_SYMBOL_GPL(audioreach_alloc_graph_pkt);
 int audioreach_send_cmd_sync(struct device *dev, gpr_device_t *gdev,
 			     struct gpr_ibasic_rsp_result_t *result, struct mutex *cmd_lock,
 			     gpr_port_t *port, wait_queue_head_t *cmd_wait,
-			     struct gpr_pkt *pkt, uint32_t rsp_opcode)
+			     const struct gpr_pkt *pkt, uint32_t rsp_opcode)
 {
 
-	struct gpr_hdr *hdr = &pkt->hdr;
+	const struct gpr_hdr *hdr = &pkt->hdr;
 	int rc;
 
 	mutex_lock(cmd_lock);
@@ -622,7 +622,7 @@ int audioreach_send_cmd_sync(struct device *dev, gpr_device_t *gdev,
 }
 EXPORT_SYMBOL_GPL(audioreach_send_cmd_sync);
 
-int audioreach_graph_send_cmd_sync(struct q6apm_graph *graph, struct gpr_pkt *pkt,
+int audioreach_graph_send_cmd_sync(struct q6apm_graph *graph, const struct gpr_pkt *pkt,
 				   uint32_t rsp_opcode)
 {
 

sound/soc/qcom/qdsp6/audioreach.h

@@ -844,8 +844,8 @@ int audioreach_map_memory_regions(struct q6apm_graph *graph,
 				  bool is_contiguous);
 int audioreach_send_cmd_sync(struct device *dev, gpr_device_t *gdev, struct gpr_ibasic_rsp_result_t *result,
 			     struct mutex *cmd_lock, gpr_port_t *port, wait_queue_head_t *cmd_wait,
-			     struct gpr_pkt *pkt, uint32_t rsp_opcode);
-int audioreach_graph_send_cmd_sync(struct q6apm_graph *graph, struct gpr_pkt *pkt,
+			     const struct gpr_pkt *pkt, uint32_t rsp_opcode);
+int audioreach_graph_send_cmd_sync(struct q6apm_graph *graph, const struct gpr_pkt *pkt,
 				   uint32_t rsp_opcode);
 int audioreach_set_media_format(struct q6apm_graph *graph,
 				const struct audioreach_module *module,

sound/soc/qcom/qdsp6/q6apm.c

@@ -29,7 +29,8 @@ struct apm_graph_mgmt_cmd {
 
 static struct q6apm *g_apm;
 
-int q6apm_send_cmd_sync(struct q6apm *apm, struct gpr_pkt *pkt, uint32_t rsp_opcode)
+int q6apm_send_cmd_sync(struct q6apm *apm, const struct gpr_pkt *pkt,
+			uint32_t rsp_opcode)
 {
 	gpr_device_t *gdev = apm->gdev;
 

sound/soc/qcom/qdsp6/q6apm.h

@@ -138,7 +138,7 @@ int q6apm_map_memory_regions(struct q6apm_graph *graph,
 int q6apm_unmap_memory_regions(struct q6apm_graph *graph,
 			       unsigned int dir);
 /* Helpers */
-int q6apm_send_cmd_sync(struct q6apm *apm, struct gpr_pkt *pkt,
+int q6apm_send_cmd_sync(struct q6apm *apm, const struct gpr_pkt *pkt,
 			uint32_t rsp_opcode);
 
 /* Callback for graph specific */