2 files changed, 85 insertions, 1 deletions

diff --git a/Documentation/devicetree/bindings/bus/imx-weim.txt b/Documentation/devicetree/bindings/bus/imx-weim.txt
index 0fd76c405208..6630d842c7a3 100644
--- a/Documentation/devicetree/bindings/bus/imx-weim.txt
+++ b/Documentation/devicetree/bindings/bus/imx-weim.txt
@@ -8,7 +8,12 @@ The actual devices are instantiated from the child nodes of a WEIM node.
 
 Required properties:
 
- - compatible:          Should be set to "fsl,<soc>-weim"
+ - compatible:          Should contain one of the following:
+                          "fsl,imx1-weim"
+                          "fsl,imx27-weim"
+                          "fsl,imx51-weim"
+                          "fsl,imx50-weim"
+                          "fsl,imx6q-weim"
  - reg:                 A resource specifier for the register space
                         (see the example below)
  - clocks:              the clock, see the example below.
@@ -19,6 +24,26 @@ Required properties:
 
                            <cs-number> 0 <physical address of mapping> <size>
 
+Optional properties:
+
+ - fsl,weim-cs-gpr:     For "fsl,imx50-weim" and "fsl,imx6q-weim" type of
+                        devices, it should be the phandle to the system General
+                        Purpose Register controller that contains WEIM CS GPR
+                        register, e.g. IOMUXC_GPR1 on i.MX6Q.  IOMUXC_GPR1[11:0]
+                        should be set up as one of the following 4 possible
+                        values depending on the CS space configuration.
+
+                        IOMUXC_GPR1[11:0]    CS0    CS1    CS2    CS3
+                        ---------------------------------------------
+                                05          128M     0M     0M     0M
+                                033          64M    64M     0M     0M
+                                0113         64M    32M    32M     0M
+                                01111        32M    32M    32M    32M
+
+                        In case that the property is absent, the reset value or
+                        what bootloader sets up in IOMUXC_GPR1[11:0] will be
+                        used.
+
 Timing property for child nodes. It is mandatory, not optional.
 
  - fsl,weim-cs-timing:  The timing array, contains timing values for the
@@ -43,6 +68,7 @@ Example for an imx6q-sabreauto board, the NOR flash connected to the WEIM:
                 #address-cells = <2>;
                 #size-cells = <1>;
                 ranges = <0 0 0x08000000 0x08000000>;
+                fsl,weim-cs-gpr = <&gpr>;
 
                 nor@0,0 {
                         compatible = "cfi-flash";
diff --git a/drivers/bus/imx-weim.c b/drivers/bus/imx-weim.c
index 3ef58c8dbf11..f8ee13c7bf7b 100644
--- a/drivers/bus/imx-weim.c
+++ b/drivers/bus/imx-weim.c
@@ -11,6 +11,9 @@
 #include <linux/clk.h>
 #include <linux/io.h>
 #include <linux/of_device.h>
+#include <linux/mfd/syscon.h>
+#include <linux/mfd/syscon/imx6q-iomuxc-gpr.h>
+#include <linux/regmap.h>
 
 struct imx_weim_devtype {
         unsigned int    cs_count;
@@ -56,6 +59,55 @@ static const struct of_device_id weim_id_table[] = {
 };
 MODULE_DEVICE_TABLE(of, weim_id_table);
 
+static int __init imx_weim_gpr_setup(struct platform_device *pdev)
+{
+        struct device_node *np = pdev->dev.of_node;
+        struct property *prop;
+        const __be32 *p;
+        struct regmap *gpr;
+        u32 gprvals[4] = {
+                05,     /* CS0(128M) CS1(0M)  CS2(0M)  CS3(0M)  */
+                033,    /* CS0(64M)  CS1(64M) CS2(0M)  CS3(0M)  */
+                0113,   /* CS0(64M)  CS1(32M) CS2(32M) CS3(0M)  */
+                01111,  /* CS0(32M)  CS1(32M) CS2(32M) CS3(32M) */
+        };
+        u32 gprval = 0;
+        u32 val;
+        int cs = 0;
+        int i = 0;
+
+        gpr = syscon_regmap_lookup_by_phandle(np, "fsl,weim-cs-gpr");
+        if (IS_ERR(gpr)) {
+                dev_dbg(&pdev->dev, "failed to find weim-cs-gpr\n");
+                return 0;
+        }
+
+        of_property_for_each_u32(np, "ranges", prop, p, val) {
+                if (i % 4 == 0) {
+                        cs = val;
+                } else if (i % 4 == 3 && val) {
+                        val = (val / SZ_32M) | 1;
+                        gprval |= val << cs * 3;
+                }
+                i++;
+        }
+
+        if (i == 0 || i % 4)
+                goto err;
+
+        for (i = 0; i < ARRAY_SIZE(gprvals); i++) {
+                if (gprval == gprvals[i]) {
+                        /* Found it. Set up IOMUXC_GPR1[11:0] with it. */
+                        regmap_update_bits(gpr, IOMUXC_GPR1, 0xfff, gprval);
+                        return 0;
+                }
+        }
+
+err:
+        dev_err(&pdev->dev, "Invalid 'ranges' configuration\n");
+        return -EINVAL;
+}
+
 /* Parse and set the timing for this device. */
 static int __init weim_timing_setup(struct device_node *np, void __iomem *base,
                                     const struct imx_weim_devtype *devtype)
@@ -92,6 +144,12 @@ static int __init weim_parse_dt(struct platform_device *pdev,
         struct device_node *child;
         int ret;
 
+        if (devtype == &imx50_weim_devtype) {
+                ret = imx_weim_gpr_setup(pdev);
+                if (ret)
+                        return ret;
+        }
+
         for_each_child_of_node(pdev->dev.of_node, child) {
                 if (!child->name)
                         continue;