/*
* 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;
};
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 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;
iim->base = devm_platform_ioremap_resource(pdev, 0);
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(dev, NULL);
if (IS_ERR(iim->clk))
return PTR_ERR(iim->clk);
cfg.name = "imx-iim",
cfg.read_only = true,
cfg.word_size = 1,
cfg.stride = 1,
cfg.reg_read = imx_iim_read,
cfg.dev = dev;
cfg.size = drvdata->nregs;
cfg.priv = iim;
nvmem = devm_nvmem_register(dev, &cfg);
return PTR_ERR_OR_ZERO(nvmem);
}
static struct platform_driver imx_iim_driver = {
.probe = imx_iim_probe,
.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");
