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0012 #include <linux/device.h>
0013 #include <linux/io.h>
0014 #include <linux/module.h>
0015 #include <linux/nvmem-provider.h>
0016 #include <linux/of.h>
0017 #include <linux/of_device.h>
0018 #include <linux/platform_device.h>
0019 #include <linux/slab.h>
0020 #include <linux/clk.h>
0021
0022 #define IIM_BANK_BASE(n) (0x800 + 0x400 * (n))
0023
0024 struct imx_iim_drvdata {
0025 unsigned int nregs;
0026 };
0027
0028 struct iim_priv {
0029 void __iomem *base;
0030 struct clk *clk;
0031 };
0032
0033 static int imx_iim_read(void *context, unsigned int offset,
0034 void *buf, size_t bytes)
0035 {
0036 struct iim_priv *iim = context;
0037 int i, ret;
0038 u8 *buf8 = buf;
0039
0040 ret = clk_prepare_enable(iim->clk);
0041 if (ret)
0042 return ret;
0043
0044 for (i = offset; i < offset + bytes; i++) {
0045 int bank = i >> 5;
0046 int reg = i & 0x1f;
0047
0048 *buf8++ = readl(iim->base + IIM_BANK_BASE(bank) + reg * 4);
0049 }
0050
0051 clk_disable_unprepare(iim->clk);
0052
0053 return 0;
0054 }
0055
0056 static struct imx_iim_drvdata imx27_drvdata = {
0057 .nregs = 2 * 32,
0058 };
0059
0060 static struct imx_iim_drvdata imx25_imx31_imx35_drvdata = {
0061 .nregs = 3 * 32,
0062 };
0063
0064 static struct imx_iim_drvdata imx51_drvdata = {
0065 .nregs = 4 * 32,
0066 };
0067
0068 static struct imx_iim_drvdata imx53_drvdata = {
0069 .nregs = 4 * 32 + 16,
0070 };
0071
0072 static const struct of_device_id imx_iim_dt_ids[] = {
0073 {
0074 .compatible = "fsl,imx25-iim",
0075 .data = &imx25_imx31_imx35_drvdata,
0076 }, {
0077 .compatible = "fsl,imx27-iim",
0078 .data = &imx27_drvdata,
0079 }, {
0080 .compatible = "fsl,imx31-iim",
0081 .data = &imx25_imx31_imx35_drvdata,
0082 }, {
0083 .compatible = "fsl,imx35-iim",
0084 .data = &imx25_imx31_imx35_drvdata,
0085 }, {
0086 .compatible = "fsl,imx51-iim",
0087 .data = &imx51_drvdata,
0088 }, {
0089 .compatible = "fsl,imx53-iim",
0090 .data = &imx53_drvdata,
0091 }, {
0092
0093 },
0094 };
0095 MODULE_DEVICE_TABLE(of, imx_iim_dt_ids);
0096
0097 static int imx_iim_probe(struct platform_device *pdev)
0098 {
0099 struct device *dev = &pdev->dev;
0100 struct iim_priv *iim;
0101 struct nvmem_device *nvmem;
0102 struct nvmem_config cfg = {};
0103 const struct imx_iim_drvdata *drvdata = NULL;
0104
0105 iim = devm_kzalloc(dev, sizeof(*iim), GFP_KERNEL);
0106 if (!iim)
0107 return -ENOMEM;
0108
0109 iim->base = devm_platform_ioremap_resource(pdev, 0);
0110 if (IS_ERR(iim->base))
0111 return PTR_ERR(iim->base);
0112
0113 drvdata = of_device_get_match_data(&pdev->dev);
0114
0115 iim->clk = devm_clk_get(dev, NULL);
0116 if (IS_ERR(iim->clk))
0117 return PTR_ERR(iim->clk);
0118
0119 cfg.name = "imx-iim",
0120 cfg.read_only = true,
0121 cfg.word_size = 1,
0122 cfg.stride = 1,
0123 cfg.reg_read = imx_iim_read,
0124 cfg.dev = dev;
0125 cfg.size = drvdata->nregs;
0126 cfg.priv = iim;
0127
0128 nvmem = devm_nvmem_register(dev, &cfg);
0129
0130 return PTR_ERR_OR_ZERO(nvmem);
0131 }
0132
0133 static struct platform_driver imx_iim_driver = {
0134 .probe = imx_iim_probe,
0135 .driver = {
0136 .name = "imx-iim",
0137 .of_match_table = imx_iim_dt_ids,
0138 },
0139 };
0140 module_platform_driver(imx_iim_driver);
0141
0142 MODULE_AUTHOR("Michael Grzeschik <m.grzeschik@pengutronix.de>");
0143 MODULE_DESCRIPTION("i.MX IIM driver");
0144 MODULE_LICENSE("GPL v2");