dmaengine: mv_xor: add suspend/resume support

[cascardo/linux.git] / drivers / dma / mv_xor.c

diff --git a/drivers/dma/mv_xor.c b/drivers/dma/mv_xor.c
index a95878c..14091f8 100644 (file)
--- a/drivers/dma/mv_xor.c
+++ b/drivers/dma/mv_xor.c
@@ -1085,6 +1085,57 @@ mv_xor_conf_mbus_windows(struct mv_xor_device *xordev,
        writel(0, base + WINDOW_OVERRIDE_CTRL(1));
 }
 
+/*
+ * Since this XOR driver is basically used only for RAID5, we don't
+ * need to care about synchronizing ->suspend with DMA activity,
+ * because the DMA engine will naturally be quiet due to the block
+ * devices being suspended.
+ */
+static int mv_xor_suspend(struct platform_device *pdev, pm_message_t state)
+{
+       struct mv_xor_device *xordev = platform_get_drvdata(pdev);
+       int i;
+
+       for (i = 0; i < MV_XOR_MAX_CHANNELS; i++) {
+               struct mv_xor_chan *mv_chan = xordev->channels[i];
+
+               if (!mv_chan)
+                       continue;
+
+               mv_chan->saved_config_reg =
+                       readl_relaxed(XOR_CONFIG(mv_chan));
+               mv_chan->saved_int_mask_reg =
+                       readl_relaxed(XOR_INTR_MASK(mv_chan));
+       }
+
+       return 0;
+}
+
+static int mv_xor_resume(struct platform_device *dev)
+{
+       struct mv_xor_device *xordev = platform_get_drvdata(dev);
+       const struct mbus_dram_target_info *dram;
+       int i;
+
+       for (i = 0; i < MV_XOR_MAX_CHANNELS; i++) {
+               struct mv_xor_chan *mv_chan = xordev->channels[i];
+
+               if (!mv_chan)
+                       continue;
+
+               writel_relaxed(mv_chan->saved_config_reg,
+                              XOR_CONFIG(mv_chan));
+               writel_relaxed(mv_chan->saved_int_mask_reg,
+                              XOR_INTR_MASK(mv_chan));
+       }
+
+       dram = mv_mbus_dram_info();
+       if (dram)
+               mv_xor_conf_mbus_windows(xordev, dram);
+
+       return 0;
+}
+
 static const struct of_device_id mv_xor_dt_ids[] = {
        { .compatible = "marvell,orion-xor", .data = (void *)XOR_MODE_IN_REG },
        { .compatible = "marvell,armada-380-xor", .data = (void *)XOR_MODE_IN_DESC },
@@ -1246,6 +1297,8 @@ err_channel_add:
 
 static struct platform_driver mv_xor_driver = {
        .probe          = mv_xor_probe,
+       .suspend        = mv_xor_suspend,
+       .resume         = mv_xor_resume,
        .driver         = {
                .name           = MV_XOR_NAME,
                .of_match_table = of_match_ptr(mv_xor_dt_ids),