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path: root/drivers/bus/imx-weim.c
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Diffstat (limited to 'drivers/bus/imx-weim.c')
-rw-r--r--drivers/bus/imx-weim.c217
1 files changed, 217 insertions, 0 deletions
diff --git a/drivers/bus/imx-weim.c b/drivers/bus/imx-weim.c
new file mode 100644
index 000000000..e98d15eaa
--- /dev/null
+++ b/drivers/bus/imx-weim.c
@@ -0,0 +1,217 @@
+/*
+ * EIM driver for Freescale's i.MX chips
+ *
+ * Copyright (C) 2013 Freescale Semiconductor, Inc.
+ *
+ * This file is licensed under the terms of the GNU General Public
+ * License version 2. This program is licensed "as is" without any
+ * warranty of any kind, whether express or implied.
+ */
+#include <linux/module.h>
+#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;
+ unsigned int cs_regs_count;
+ unsigned int cs_stride;
+};
+
+static const struct imx_weim_devtype imx1_weim_devtype = {
+ .cs_count = 6,
+ .cs_regs_count = 2,
+ .cs_stride = 0x08,
+};
+
+static const struct imx_weim_devtype imx27_weim_devtype = {
+ .cs_count = 6,
+ .cs_regs_count = 3,
+ .cs_stride = 0x10,
+};
+
+static const struct imx_weim_devtype imx50_weim_devtype = {
+ .cs_count = 4,
+ .cs_regs_count = 6,
+ .cs_stride = 0x18,
+};
+
+static const struct imx_weim_devtype imx51_weim_devtype = {
+ .cs_count = 6,
+ .cs_regs_count = 6,
+ .cs_stride = 0x18,
+};
+
+static const struct of_device_id weim_id_table[] = {
+ /* i.MX1/21 */
+ { .compatible = "fsl,imx1-weim", .data = &imx1_weim_devtype, },
+ /* i.MX25/27/31/35 */
+ { .compatible = "fsl,imx27-weim", .data = &imx27_weim_devtype, },
+ /* i.MX50/53/6Q */
+ { .compatible = "fsl,imx50-weim", .data = &imx50_weim_devtype, },
+ { .compatible = "fsl,imx6q-weim", .data = &imx50_weim_devtype, },
+ /* i.MX51 */
+ { .compatible = "fsl,imx51-weim", .data = &imx51_weim_devtype, },
+ { }
+};
+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)
+{
+ u32 cs_idx, value[devtype->cs_regs_count];
+ int i, ret;
+
+ /* get the CS index from this child node's "reg" property. */
+ ret = of_property_read_u32(np, "reg", &cs_idx);
+ if (ret)
+ return ret;
+
+ if (cs_idx >= devtype->cs_count)
+ return -EINVAL;
+
+ ret = of_property_read_u32_array(np, "fsl,weim-cs-timing",
+ value, devtype->cs_regs_count);
+ if (ret)
+ return ret;
+
+ /* set the timing for WEIM */
+ for (i = 0; i < devtype->cs_regs_count; i++)
+ writel(value[i], base + cs_idx * devtype->cs_stride + i * 4);
+
+ return 0;
+}
+
+static int __init weim_parse_dt(struct platform_device *pdev,
+ void __iomem *base)
+{
+ const struct of_device_id *of_id = of_match_device(weim_id_table,
+ &pdev->dev);
+ const struct imx_weim_devtype *devtype = of_id->data;
+ struct device_node *child;
+ int ret, have_child = 0;
+
+ 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;
+
+ ret = weim_timing_setup(child, base, devtype);
+ if (ret)
+ dev_warn(&pdev->dev, "%s set timing failed.\n",
+ child->full_name);
+ else
+ have_child = 1;
+ }
+
+ if (have_child)
+ ret = of_platform_populate(pdev->dev.of_node,
+ of_default_bus_match_table,
+ NULL, &pdev->dev);
+ if (ret)
+ dev_err(&pdev->dev, "%s fail to create devices.\n",
+ pdev->dev.of_node->full_name);
+ return ret;
+}
+
+static int __init weim_probe(struct platform_device *pdev)
+{
+ struct resource *res;
+ struct clk *clk;
+ void __iomem *base;
+ int ret;
+
+ /* get the resource */
+ res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+ base = devm_ioremap_resource(&pdev->dev, res);
+ if (IS_ERR(base))
+ return PTR_ERR(base);
+
+ /* get the clock */
+ clk = devm_clk_get(&pdev->dev, NULL);
+ if (IS_ERR(clk))
+ return PTR_ERR(clk);
+
+ ret = clk_prepare_enable(clk);
+ if (ret)
+ return ret;
+
+ /* parse the device node */
+ ret = weim_parse_dt(pdev, base);
+ if (ret)
+ clk_disable_unprepare(clk);
+ else
+ dev_info(&pdev->dev, "Driver registered.\n");
+
+ return ret;
+}
+
+static struct platform_driver weim_driver = {
+ .driver = {
+ .name = "imx-weim",
+ .of_match_table = weim_id_table,
+ },
+};
+module_platform_driver_probe(weim_driver, weim_probe);
+
+MODULE_AUTHOR("Freescale Semiconductor Inc.");
+MODULE_DESCRIPTION("i.MX EIM Controller Driver");
+MODULE_LICENSE("GPL");