2 * EIM driver for Freescale's i.MX chips
4 * Copyright (C) 2013 Freescale Semiconductor, Inc.
6 * This file is licensed under the terms of the GNU General Public
7 * License version 2. This program is licensed "as is" without any
8 * warranty of any kind, whether express or implied.
10 #include <linux/module.h>
11 #include <linux/clk.h>
13 #include <linux/of_device.h>
20 static const struct of_device_id weim_id_table[] = {
21 { .compatible = "fsl,imx6q-weim", },
24 MODULE_DEVICE_TABLE(of, weim_id_table);
26 #define CS_TIMING_LEN 6
27 #define CS_REG_RANGE 0x18
29 /* Parse and set the timing for this device. */
31 weim_timing_setup(struct platform_device *pdev, struct device_node *np)
33 struct imx_weim *weim = platform_get_drvdata(pdev);
34 u32 value[CS_TIMING_LEN];
39 /* get the CS index from this child node's "reg" property. */
40 ret = of_property_read_u32(np, "reg", &cs_idx);
44 /* The weim has four chip selects. */
48 ret = of_property_read_u32_array(np, "fsl,weim-cs-timing",
49 value, CS_TIMING_LEN);
53 /* set the timing for WEIM */
54 for (i = 0; i < CS_TIMING_LEN; i++)
55 writel(value[i], weim->base + cs_idx * CS_REG_RANGE + i * 4);
59 static int weim_parse_dt(struct platform_device *pdev)
61 struct device_node *child;
64 for_each_child_of_node(pdev->dev.of_node, child) {
68 ret = weim_timing_setup(pdev, child);
70 dev_err(&pdev->dev, "%s set timing failed.\n",
76 ret = of_platform_populate(pdev->dev.of_node, NULL, NULL, &pdev->dev);
78 dev_err(&pdev->dev, "%s fail to create devices.\n",
79 pdev->dev.of_node->full_name);
83 static int weim_probe(struct platform_device *pdev)
85 struct imx_weim *weim;
89 weim = devm_kzalloc(&pdev->dev, sizeof(*weim), GFP_KERNEL);
94 platform_set_drvdata(pdev, weim);
96 /* get the resource */
97 res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
98 weim->base = devm_ioremap_resource(&pdev->dev, res);
99 if (IS_ERR(weim->base)) {
100 ret = PTR_ERR(weim->base);
105 weim->clk = devm_clk_get(&pdev->dev, NULL);
106 if (IS_ERR(weim->clk))
109 ret = clk_prepare_enable(weim->clk);
113 /* parse the device node */
114 ret = weim_parse_dt(pdev);
116 clk_disable_unprepare(weim->clk);
120 dev_info(&pdev->dev, "WEIM driver registered.\n");
127 static struct platform_driver weim_driver = {
130 .of_match_table = weim_id_table,
135 module_platform_driver(weim_driver);
136 MODULE_AUTHOR("Freescale Semiconductor Inc.");
137 MODULE_DESCRIPTION("i.MX EIM Controller Driver");
138 MODULE_LICENSE("GPL");