diff options
Diffstat (limited to 'drivers/nvmem/imx-iim.c')
| -rw-r--r-- | drivers/nvmem/imx-iim.c | 157 |
1 files changed, 157 insertions, 0 deletions
diff --git a/drivers/nvmem/imx-iim.c b/drivers/nvmem/imx-iim.c new file mode 100644 index 000000000..6651e4cdc --- /dev/null +++ b/drivers/nvmem/imx-iim.c @@ -0,0 +1,157 @@ +/* + * 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 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(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"); |