diff options
Diffstat (limited to 'drivers/nvmem/imx-ocotp.c')
| -rw-r--r-- | drivers/nvmem/imx-ocotp.c | 154 |
1 files changed, 154 insertions, 0 deletions
diff --git a/drivers/nvmem/imx-ocotp.c b/drivers/nvmem/imx-ocotp.c new file mode 100644 index 000000000000..b7971d410b60 --- /dev/null +++ b/drivers/nvmem/imx-ocotp.c @@ -0,0 +1,154 @@ +/* + * i.MX6 OCOTP fusebox driver + * + * Copyright (c) 2015 Pengutronix, Philipp Zabel <p.zabel@pengutronix.de> + * + * Based on the barebox ocotp 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/regmap.h> +#include <linux/slab.h> + +struct ocotp_priv { + struct device *dev; + void __iomem *base; + unsigned int nregs; +}; + +static int imx_ocotp_read(void *context, const void *reg, size_t reg_size, + void *val, size_t val_size) +{ + struct ocotp_priv *priv = context; + unsigned int offset = *(u32 *)reg; + unsigned int count; + int i; + u32 index; + + index = offset >> 2; + count = val_size >> 2; + + if (count > (priv->nregs - index)) + count = priv->nregs - index; + + for (i = index; i < (index + count); i++) { + *(u32 *)val = readl(priv->base + 0x400 + i * 0x10); + val += 4; + } + + return (i - index) * 4; +} + +static int imx_ocotp_write(void *context, const void *data, size_t count) +{ + /* Not implemented */ + return 0; +} + +static struct regmap_bus imx_ocotp_bus = { + .read = imx_ocotp_read, + .write = imx_ocotp_write, + .reg_format_endian_default = REGMAP_ENDIAN_NATIVE, + .val_format_endian_default = REGMAP_ENDIAN_NATIVE, +}; + +static bool imx_ocotp_writeable_reg(struct device *dev, unsigned int reg) +{ + return false; +} + +static struct regmap_config imx_ocotp_regmap_config = { + .reg_bits = 32, + .val_bits = 32, + .reg_stride = 4, + .writeable_reg = imx_ocotp_writeable_reg, + .name = "imx-ocotp", +}; + +static struct nvmem_config imx_ocotp_nvmem_config = { + .name = "imx-ocotp", + .read_only = true, + .owner = THIS_MODULE, +}; + +static const struct of_device_id imx_ocotp_dt_ids[] = { + { .compatible = "fsl,imx6q-ocotp", (void *)128 }, + { .compatible = "fsl,imx6sl-ocotp", (void *)32 }, + { .compatible = "fsl,imx6sx-ocotp", (void *)128 }, + { }, +}; +MODULE_DEVICE_TABLE(of, imx_ocotp_dt_ids); + +static int imx_ocotp_probe(struct platform_device *pdev) +{ + const struct of_device_id *of_id; + struct device *dev = &pdev->dev; + struct resource *res; + struct regmap *regmap; + struct ocotp_priv *priv; + struct nvmem_device *nvmem; + + priv = devm_kzalloc(dev, sizeof(*priv), GFP_KERNEL); + if (!priv) + return -ENOMEM; + + res = platform_get_resource(pdev, IORESOURCE_MEM, 0); + priv->base = devm_ioremap_resource(dev, res); + if (IS_ERR(priv->base)) + return PTR_ERR(priv->base); + + of_id = of_match_device(imx_ocotp_dt_ids, dev); + priv->nregs = (unsigned int)of_id->data; + imx_ocotp_regmap_config.max_register = 4 * priv->nregs - 4; + + regmap = devm_regmap_init(dev, &imx_ocotp_bus, priv, + &imx_ocotp_regmap_config); + if (IS_ERR(regmap)) { + dev_err(dev, "regmap init failed\n"); + return PTR_ERR(regmap); + } + imx_ocotp_nvmem_config.dev = dev; + nvmem = nvmem_register(&imx_ocotp_nvmem_config); + if (IS_ERR(nvmem)) + return PTR_ERR(nvmem); + + platform_set_drvdata(pdev, nvmem); + + return 0; +} + +static int imx_ocotp_remove(struct platform_device *pdev) +{ + struct nvmem_device *nvmem = platform_get_drvdata(pdev); + + return nvmem_unregister(nvmem); +} + +static struct platform_driver imx_ocotp_driver = { + .probe = imx_ocotp_probe, + .remove = imx_ocotp_remove, + .driver = { + .name = "imx_ocotp", + .of_match_table = imx_ocotp_dt_ids, + }, +}; +module_platform_driver(imx_ocotp_driver); + +MODULE_AUTHOR("Philipp Zabel <p.zabel@pengutronix.de>"); +MODULE_DESCRIPTION("i.MX6 OCOTP fuse box driver"); +MODULE_LICENSE("GPL v2"); |