[PATCH 2/3] nvmem: mediatek: Add Mediatek EFUSE driver

Srinivas Kandagatla
2015-10-26T09:56:24Z

On 16/10/15 09:39, andrew-ct.chen at mediatek.com wrote:
> From: Andrew-CT Chen <andrew-ct.chen@mediatek.com>
>
> Add Mediatek EFUSE driver to access hardware data like
> thermal sensor calibration or HDMI impedance.
>
> Signed-off-by: Andrew-CT Chen <andrew-ct.chen@mediatek.com>

Dirver looks pretty simple, below are few minor nits.

Please rebase this patch on top of v4.4-rc1 once its released in few
weeks, so that I can queue this driver for v4.5.

> ---
> drivers/nvmem/Kconfig | 11 ++++++
> drivers/nvmem/Makefile | 1 +
> drivers/nvmem/mtk-efuse.c | 89 +++++++++++++++++++++++++++++++++++++++++++++++
> 3 files changed, 101 insertions(+)
> create mode 100644 drivers/nvmem/mtk-efuse.c
>
> diff --git a/drivers/nvmem/Kconfig b/drivers/nvmem/Kconfig
> index 8db2978..1bd5badc 100644
> --- a/drivers/nvmem/Kconfig
> +++ b/drivers/nvmem/Kconfig
> @@ -14,6 +14,17 @@ menuconfig NVMEM
>
> if NVMEM
>
> +config MTK_EFUSE
> + tristate "Mediatek SoCs EFUSE support"
> + depends on ARCH_MEDIATEK || COMPILE_TEST
> + select REGMAP_MMIO
> + help
> + This is a driver to access hardware related data like sensor
> + calibration, HDMI impedance etc.
> +
> + This driver can also be built as a module. If so, the module
> + will be called efuse-mtk.
> +
> config QCOM_QFPROM
> tristate "QCOM QFPROM Support"
> depends on ARCH_QCOM || COMPILE_TEST
> diff --git a/drivers/nvmem/Makefile b/drivers/nvmem/Makefile
> index 4328b93..916b727 100644
> --- a/drivers/nvmem/Makefile
> +++ b/drivers/nvmem/Makefile
> @@ -6,6 +6,7 @@ obj-$(CONFIG_NVMEM) += nvmem_core.o
> nvmem_core-y := core.o
>
> # Devices
> +obj-$(CONFIG_MTK_EFUSE) += mtk-efuse.o

For consistency reasons, could you do this similar to other drivers.

> obj-$(CONFIG_QCOM_QFPROM) += nvmem_qfprom.o
> nvmem_qfprom-y := qfprom.o
> obj-$(CONFIG_NVMEM_SUNXI_SID) += nvmem_sunxi_sid.o
> diff --git a/drivers/nvmem/mtk-efuse.c b/drivers/nvmem/mtk-efuse.c
> new file mode 100644
> index 0000000..9021c0b
> --- /dev/null
> +++ b/drivers/nvmem/mtk-efuse.c
> @@ -0,0 +1,89 @@
> +/*
> + * Copyright (c) 2015 MediaTek Inc.
> + * Author: Andrew-CT Chen <andrew-ct.chen@mediatek.com>
> + *
> + * 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.
> + *
> + * This program is distributed in the hope that it will be useful,
> + * but WITHOUT ANY WARRANTY; without even the implied warranty of
> + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
> + * GNU General Public License for more details.
> + */
> +
> +#include <linux/device.h>
> +#include <linux/module.h>
> +#include <linux/nvmem-provider.h>
> +#include <linux/platform_device.h>
> +#include <linux/regmap.h>
> +
> +static struct regmap_config mtk_regmap_config = {
> + .reg_bits = 32,
> + .val_bits = 32,
> + .reg_stride = 4,
> +};
> +
> +static int mtk_efuse_probe(struct platform_device *pdev)
> +{
> + struct device *dev = &pdev->dev;
> + struct resource *res;
> + struct nvmem_device *nvmem;
> + struct nvmem_config *econfig;
> + struct regmap *regmap;
> + void __iomem *base;
> +
> + res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
> + base = devm_ioremap_resource(dev, res);
> + if (IS_ERR(base))
> + return PTR_ERR(base);
> +
> + econfig = devm_kzalloc(dev, sizeof(*econfig), GFP_KERNEL);
> + if (!econfig)
> + return -ENOMEM;
Why not use static econfig variable?

> +
> + mtk_regmap_config.max_register = resource_size(res) - 1;
> +
> + regmap = devm_regmap_init_mmio(dev, base, &mtk_regmap_config);
> + if (IS_ERR(regmap)) {
> + dev_err(dev, "regmap init failed\n");
> + return PTR_ERR(regmap);
> + }
> +
> + econfig->dev = dev;
> + econfig->owner = THIS_MODULE;
> + nvmem = nvmem_register(econfig);
> + if (IS_ERR(nvmem))
> + return PTR_ERR(nvmem);
> +
> + platform_set_drvdata(pdev, nvmem);
> +
> + return 0;
> +}
> +
> +static int mtk_efuse_remove(struct platform_device *pdev)
> +{
> + struct nvmem_device *nvmem = platform_get_drvdata(pdev);
> +
> + return nvmem_unregister(nvmem);
> +}
> +
> +static const struct of_device_id mtk_efuse_of_match[] = {
> + { .compatible = "mediatek,mt8135-efuse",},
> + { .compatible = "mediatek,mt8173-efuse",},
> + {/* sentinel */},
> +};
> +MODULE_DEVICE_TABLE(of, mtk_efuse_of_match);
> +
> +static struct platform_driver mtk_efuse_driver = {
> + .probe = mtk_efuse_probe,
> + .remove = mtk_efuse_remove,
> + .driver = {
> + .name = "mediatek,efuse",
> + .of_match_table = mtk_efuse_of_match,
> + },
> +};
> +module_platform_driver(mtk_efuse_driver);
> +MODULE_AUTHOR("Andrew-CT Chen <andrew-ct.chen@mediatek.com>");
> +MODULE_DESCRIPTION("Mediatek EFUSE driver");
> +MODULE_LICENSE("GPL v2");
>