[PATCH v16 4/5] CMDQ: suspend and resume

[HS Liao]

take suspend and resume into consideration

Signed-off-by: HS Liao <hs.l...@mediatek.com>
---
 drivers/mailbox/mtk-cmdq-mailbox.c | 44 ++++++++++++++++++++++++++++++++++++++
 1 file changed, 44 insertions(+)

diff --git a/drivers/mailbox/mtk-cmdq-mailbox.c 
b/drivers/mailbox/mtk-cmdq-mailbox.c
index d086fd8..747bcd3 100644
--- a/drivers/mailbox/mtk-cmdq-mailbox.c
+++ b/drivers/mailbox/mtk-cmdq-mailbox.c
@@ -81,6 +81,7 @@ struct cmdq {
        u32                     irq;
        struct cmdq_thread      thread[CMDQ_THR_MAX_COUNT];
        struct clk              *clock;
+       bool                    suspended;
 };
 
 static int cmdq_thread_suspend(struct cmdq *cmdq, struct cmdq_thread *thread)
@@ -206,6 +207,9 @@ static void cmdq_task_exec(struct cmdq_pkt *pkt, struct 
cmdq_thread *thread)
 
        cmdq = dev_get_drvdata(thread->chan->mbox->dev);
 
+       /* Client should not flush new tasks if suspended. */
+       WARN_ON(cmdq->suspended);
+
        task = kzalloc(sizeof(*task), GFP_ATOMIC);
        task->cmdq = cmdq;
        INIT_LIST_HEAD(&task->list_entry);
@@ -409,6 +413,39 @@ static void cmdq_thread_handle_timeout(unsigned long data)
        spin_unlock_irqrestore(&thread->chan->lock, flags);
 }
 
+static int cmdq_suspend(struct device *dev)
+{
+       struct cmdq *cmdq = dev_get_drvdata(dev);
+       struct cmdq_thread *thread;
+       int i;
+       bool task_running = false;
+
+       cmdq->suspended = true;
+
+       for (i = 0; i < ARRAY_SIZE(cmdq->thread); i++) {
+               thread = &cmdq->thread[i];
+               if (!list_empty(&thread->task_busy_list)) {
+                       task_running = true;
+                       break;
+               }
+       }
+
+       if (task_running)
+               dev_warn(dev, "exist running task(s) in suspend\n");
+
+       clk_unprepare(cmdq->clock);
+       return 0;
+}
+
+static int cmdq_resume(struct device *dev)
+{
+       struct cmdq *cmdq = dev_get_drvdata(dev);
+
+       WARN_ON(clk_prepare(cmdq->clock) < 0);
+       cmdq->suspended = false;
+       return 0;
+}
+
 static int cmdq_remove(struct platform_device *pdev)
 {
        struct cmdq *cmdq = platform_get_drvdata(pdev);
@@ -532,9 +569,15 @@ static int cmdq_probe(struct platform_device *pdev)
 
        platform_set_drvdata(pdev, cmdq);
        WARN_ON(clk_prepare(cmdq->clock) < 0);
+
        return 0;
 }
 
+static const struct dev_pm_ops cmdq_pm_ops = {
+       .suspend = cmdq_suspend,
+       .resume = cmdq_resume,
+};
+
 static const struct of_device_id cmdq_of_ids[] = {
        {.compatible = "mediatek,mt8173-gce",},
        {}
@@ -545,6 +588,7 @@ static int cmdq_probe(struct platform_device *pdev)
        .remove = cmdq_remove,
        .driver = {
                .name = "mtk_cmdq",
+               .pm = &cmdq_pm_ops,
                .of_match_table = cmdq_of_ids,
        }
 };
-- 
1.9.1