GCE cannot know the register base address, this function
can help cmdq client to get the cmdq_client_reg structure.

Signed-off-by: Bibby Hsieh <redacted>
---
 drivers/soc/mediatek/mtk-cmdq-helper.c | 24 ++++++++++++++++++++++++
 include/linux/soc/mediatek/mtk-cmdq.h  | 20 ++++++++++++++++++++
 2 files changed, 44 insertions(+)

diff --git a/drivers/soc/mediatek/mtk-cmdq-helper.c b/drivers/soc/mediatek/mtk-cmdq-helper.c
index 70ad4d806fac..fac4d33fd520 100644
--- a/drivers/soc/mediatek/mtk-cmdq-helper.c
+++ b/drivers/soc/mediatek/mtk-cmdq-helper.c

@@ -27,6 +27,30 @@ struct cmdq_instruction {
        u8 op;
 };

+int cmdq_dev_get_client_reg(struct device *dev,
+                           struct cmdq_client_reg *client_reg, int idx)
+{
+       struct of_phandle_args spec;
+
+       if (!client_reg)
+               return -EINVAL;
+
+       if (of_parse_phandle_with_args(dev->of_node, "mediatek,gce-client-reg",
+                                      "#subsys-cells", idx, &spec)) {
+               dev_err(dev, "can't parse gce-client-reg property (%d)", idx);
+
+               return -EINVAL;
+       }
+
+       client_reg->subsys = spec.args[0];
+       client_reg->offset = spec.args[1];
+       client_reg->size = spec.args[2];
+       of_node_put(spec.np);
+
+       return 0;
+}
+EXPORT_SYMBOL(cmdq_dev_get_client_reg);
+
 static void cmdq_client_timeout(struct timer_list *t)
 {
        struct cmdq_client *client = from_timer(client, t, timer);

diff --git a/include/linux/soc/mediatek/mtk-cmdq.h b/include/linux/soc/mediatek/mtk-cmdq.h
index a345870a6d10..2e2a2274c231 100644
--- a/include/linux/soc/mediatek/mtk-cmdq.h
+++ b/include/linux/soc/mediatek/mtk-cmdq.h

@@ -15,6 +15,12 @@

 struct cmdq_pkt;

+struct cmdq_client_reg {
+       u8 subsys;
+       u16 offset;
+       u16 size;
+};
+
 struct cmdq_client {
        spinlock_t lock;
        u32 pkt_cnt;

@@ -142,4 +148,18 @@ int cmdq_pkt_flush_async(struct cmdq_pkt *pkt, cmdq_async_flush_cb cb,
  */
 int cmdq_pkt_flush(struct cmdq_pkt *pkt);

+/**
+ * cmdq_dev_get_client_reg() - parse cmdq client reg from the device node of CMDQ client