1 files changed, 72 insertions, 0 deletions

diff --git a/arch/arm/mach-imx/mmdc.c b/arch/arm/mach-imx/mmdc.c
new file mode 100644
index 000000000000..c461e98496c3
--- /dev/null
+++ b/arch/arm/mach-imx/mmdc.c
@@ -0,0 +1,72 @@
+/*
+ * Copyright 2011 Freescale Semiconductor, Inc.
+ * Copyright 2011 Linaro Ltd.
+ *
+ * The code contained herein is licensed under the GNU General Public
+ * License. You may obtain a copy of the GNU General Public License
+ * Version 2 or later at the following locations:
+ *
+ * http://www.opensource.org/licenses/gpl-license.html
+ * http://www.gnu.org/copyleft/gpl.html
+ */
+
+#include <linux/init.h>
+#include <linux/io.h>
+#include <linux/module.h>
+#include <linux/of.h>
+#include <linux/of_address.h>
+#include <linux/of_device.h>
+
+#define MMDC_MAPSR              0x404
+#define BP_MMDC_MAPSR_PSD       0
+#define BP_MMDC_MAPSR_PSS       4
+
+static int __devinit imx_mmdc_probe(struct platform_device *pdev)
+{
+        struct device_node *np = pdev->dev.of_node;
+        void __iomem *mmdc_base, *reg;
+        u32 val;
+        int timeout = 0x400;
+
+        mmdc_base = of_iomap(np, 0);
+        WARN_ON(!mmdc_base);
+
+        reg = mmdc_base + MMDC_MAPSR;
+
+        /* Enable automatic power saving */
+        val = readl_relaxed(reg);
+        val &= ~(1 << BP_MMDC_MAPSR_PSD);
+        writel_relaxed(val, reg);
+
+        /* Ensure it's successfully enabled */
+        while (!(readl_relaxed(reg) & 1 << BP_MMDC_MAPSR_PSS) && --timeout)
+                cpu_relax();
+
+        if (unlikely(!timeout)) {
+                pr_warn("%s: failed to enable automatic power saving\n",
+                        __func__);
+                return -EBUSY;
+        }
+
+        return 0;
+}
+
+static struct of_device_id imx_mmdc_dt_ids[] = {
+        { .compatible = "fsl,imx6q-mmdc", },
+        { /* sentinel */ }
+};
+
+static struct platform_driver imx_mmdc_driver = {
+        .driver         = {
+                .name   = "imx-mmdc",
+                .owner  = THIS_MODULE,
+                .of_match_table = imx_mmdc_dt_ids,
+        },
+        .probe          = imx_mmdc_probe,
+};
+
+static int __init imx_mmdc_init(void)
+{
+        return platform_driver_register(&imx_mmdc_driver);
+}
+postcore_initcall(imx_mmdc_init);