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Diffstat (limited to 'drivers/nvmem/imx-iim.c')
-rw-r--r--drivers/nvmem/imx-iim.c173
1 files changed, 173 insertions, 0 deletions
diff --git a/drivers/nvmem/imx-iim.c b/drivers/nvmem/imx-iim.c
new file mode 100644
index 000000000000..52ff65e0673f
--- /dev/null
+++ b/drivers/nvmem/imx-iim.c
@@ -0,0 +1,173 @@
+/*
+ * i.MX IIM driver
+ *
+ * Copyright (c) 2017 Pengutronix, Michael Grzeschik <m.grzeschik@pengutronix.de>
+ *
+ * Based on the barebox iim driver,
+ * Copyright (c) 2010 Baruch Siach <baruch@tkos.co.il>,
+ * Orex Computed Radiography
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2
+ * as published by the Free Software Foundation.
+ *
+ * http://www.opensource.org/licenses/gpl-license.html
+ * http://www.gnu.org/copyleft/gpl.html
+ */
+
+#include <linux/device.h>
+#include <linux/io.h>
+#include <linux/module.h>
+#include <linux/nvmem-provider.h>
+#include <linux/of.h>
+#include <linux/of_device.h>
+#include <linux/platform_device.h>
+#include <linux/slab.h>
+#include <linux/clk.h>
+
+#define IIM_BANK_BASE(n) (0x800 + 0x400 * (n))
+
+struct imx_iim_drvdata {
+ unsigned int nregs;
+};
+
+struct iim_priv {
+ void __iomem *base;
+ struct clk *clk;
+ struct nvmem_config nvmem;
+};
+
+static int imx_iim_read(void *context, unsigned int offset,
+ void *buf, size_t bytes)
+{
+ struct iim_priv *iim = context;
+ int i, ret;
+ u8 *buf8 = buf;
+
+ ret = clk_prepare_enable(iim->clk);
+ if (ret)
+ return ret;
+
+ for (i = offset; i < offset + bytes; i++) {
+ int bank = i >> 5;
+ int reg = i & 0x1f;
+
+ *buf8++ = readl(iim->base + IIM_BANK_BASE(bank) + reg * 4);
+ }
+
+ clk_disable_unprepare(iim->clk);
+
+ return 0;
+}
+
+static struct imx_iim_drvdata imx27_drvdata = {
+ .nregs = 2 * 32,
+};
+
+static struct imx_iim_drvdata imx25_imx31_imx35_drvdata = {
+ .nregs = 3 * 32,
+};
+
+static struct imx_iim_drvdata imx51_drvdata = {
+ .nregs = 4 * 32,
+};
+
+static struct imx_iim_drvdata imx53_drvdata = {
+ .nregs = 4 * 32 + 16,
+};
+
+static const struct of_device_id imx_iim_dt_ids[] = {
+ {
+ .compatible = "fsl,imx25-iim",
+ .data = &imx25_imx31_imx35_drvdata,
+ }, {
+ .compatible = "fsl,imx27-iim",
+ .data = &imx27_drvdata,
+ }, {
+ .compatible = "fsl,imx31-iim",
+ .data = &imx25_imx31_imx35_drvdata,
+ }, {
+ .compatible = "fsl,imx35-iim",
+ .data = &imx25_imx31_imx35_drvdata,
+ }, {
+ .compatible = "fsl,imx51-iim",
+ .data = &imx51_drvdata,
+ }, {
+ .compatible = "fsl,imx53-iim",
+ .data = &imx53_drvdata,
+ }, {
+ /* sentinel */
+ },
+};
+MODULE_DEVICE_TABLE(of, imx_iim_dt_ids);
+
+static int imx_iim_probe(struct platform_device *pdev)
+{
+ const struct of_device_id *of_id;
+ struct device *dev = &pdev->dev;
+ struct resource *res;
+ struct iim_priv *iim;
+ struct nvmem_device *nvmem;
+ struct nvmem_config *cfg;
+ const struct imx_iim_drvdata *drvdata = NULL;
+
+ iim = devm_kzalloc(dev, sizeof(*iim), GFP_KERNEL);
+ if (!iim)
+ return -ENOMEM;
+
+ res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+ iim->base = devm_ioremap_resource(dev, res);
+ if (IS_ERR(iim->base))
+ return PTR_ERR(iim->base);
+
+ of_id = of_match_device(imx_iim_dt_ids, dev);
+ if (!of_id)
+ return -ENODEV;
+
+ drvdata = of_id->data;
+
+ iim->clk = devm_clk_get(&pdev->dev, NULL);
+ if (IS_ERR(iim->clk))
+ return PTR_ERR(iim->clk);
+
+ cfg = &iim->nvmem;
+
+ cfg->name = "imx-iim",
+ cfg->read_only = true,
+ cfg->word_size = 1,
+ cfg->stride = 1,
+ cfg->owner = THIS_MODULE,
+ cfg->reg_read = imx_iim_read,
+ cfg->dev = dev;
+ cfg->size = drvdata->nregs;
+ cfg->priv = iim;
+
+ nvmem = nvmem_register(cfg);
+ if (IS_ERR(nvmem))
+ return PTR_ERR(nvmem);
+
+ platform_set_drvdata(pdev, nvmem);
+
+ return 0;
+}
+
+static int imx_iim_remove(struct platform_device *pdev)
+{
+ struct nvmem_device *nvmem = platform_get_drvdata(pdev);
+
+ return nvmem_unregister(nvmem);
+}
+
+static struct platform_driver imx_iim_driver = {
+ .probe = imx_iim_probe,
+ .remove = imx_iim_remove,
+ .driver = {
+ .name = "imx-iim",
+ .of_match_table = imx_iim_dt_ids,
+ },
+};
+module_platform_driver(imx_iim_driver);
+
+MODULE_AUTHOR("Michael Grzeschik <m.grzeschik@pengutronix.de>");
+MODULE_DESCRIPTION("i.MX IIM driver");
+MODULE_LICENSE("GPL v2");