[net-next PATCH v12 11/13] nvmem: an8855: Add support for Airoha AN8855 Switch EFUSE
From: Christian Marangi <ansuelsmth@gmail.com>
Date: 2025-03-09 17:28:09
Also in:
linux-arm-kernel, linux-devicetree, linux-mediatek, lkml
Subsystem:
nvmem framework, the rest · Maintainers:
Srinivas Kandagatla, Linus Torvalds
Add support for Airoha AN8855 Switch EFUSE. These EFUSE might be used for calibration data for the internal switch PHYs. Signed-off-by: Christian Marangi <ansuelsmth@gmail.com> --- MAINTAINERS | 1 + drivers/nvmem/Kconfig | 11 +++++++ drivers/nvmem/Makefile | 2 ++ drivers/nvmem/an8855-efuse.c | 63 ++++++++++++++++++++++++++++++++++++ 4 files changed, 77 insertions(+) create mode 100644 drivers/nvmem/an8855-efuse.c
diff --git a/MAINTAINERS b/MAINTAINERS
index 8c83c446a69d..938b81767862 100644
--- a/MAINTAINERS
+++ b/MAINTAINERS@@ -732,6 +732,7 @@ F: Documentation/devicetree/bindings/net/dsa/airoha,an8855-switch.yaml F: Documentation/devicetree/bindings/nvmem/airoha,an8855-efuse.yaml F: drivers/mfd/airoha-an8855.c F: drivers/net/mdio/mdio-an8855.c +F: drivers/nvmem/an8855-efuse.c AIROHA ETHERNET DRIVER M: Lorenzo Bianconi <lorenzo@kernel.org>
diff --git a/drivers/nvmem/Kconfig b/drivers/nvmem/Kconfig
index 8671b7c974b9..ca96c6ea685a 100644
--- a/drivers/nvmem/Kconfig
+++ b/drivers/nvmem/Kconfig@@ -28,6 +28,17 @@ source "drivers/nvmem/layouts/Kconfig" # Devices +config NVMEM_AN8855_EFUSE + tristate "Airoha AN8855 eFuse support" + depends on MFD_AIROHA_AN8855 || COMPILE_TEST + help + Say y here to enable support for reading eFuses on Airoha AN8855 + Switch. These are e.g. used to store factory programmed + calibration data required for the PHY. + + This driver can also be built as a module. If so, the module will + be called nvmem-an8855-efuse. + config NVMEM_APPLE_EFUSES tristate "Apple eFuse support" depends on ARCH_APPLE || COMPILE_TEST
diff --git a/drivers/nvmem/Makefile b/drivers/nvmem/Makefile
index 5b77bbb6488b..c732132c0e45 100644
--- a/drivers/nvmem/Makefile
+++ b/drivers/nvmem/Makefile@@ -10,6 +10,8 @@ nvmem_layouts-y := layouts.o obj-y += layouts/ # Devices +obj-$(CONFIG_NVMEM_AN8855_EFUSE) += nvmem-an8855-efuse.o +nvmem-an8855-efuse-y := an8855-efuse.o obj-$(CONFIG_NVMEM_APPLE_EFUSES) += nvmem-apple-efuses.o nvmem-apple-efuses-y := apple-efuses.o obj-$(CONFIG_NVMEM_BCM_OCOTP) += nvmem-bcm-ocotp.o
diff --git a/drivers/nvmem/an8855-efuse.c b/drivers/nvmem/an8855-efuse.c
new file mode 100644
index 000000000000..cd1564379098
--- /dev/null
+++ b/drivers/nvmem/an8855-efuse.c@@ -0,0 +1,63 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * Airoha AN8855 Switch EFUSE Driver + */ + +#include <linux/mod_devicetable.h> +#include <linux/module.h> +#include <linux/nvmem-provider.h> +#include <linux/platform_device.h> +#include <linux/regmap.h> + +#define AN8855_EFUSE_CELL 50 + +#define AN8855_EFUSE_DATA0 0x1000a500 +#define AN8855_EFUSE_R50O GENMASK(30, 24) + +static int an8855_efuse_read(void *context, unsigned int offset, + void *val, size_t bytes) +{ + struct regmap *regmap = context; + + return regmap_bulk_read(regmap, AN8855_EFUSE_DATA0 + offset, + val, bytes / sizeof(u32)); +} + +static int an8855_efuse_probe(struct platform_device *pdev) +{ + struct nvmem_config an8855_nvmem_config = { + .name = "an8855-efuse", + .size = AN8855_EFUSE_CELL * sizeof(u32), + .stride = sizeof(u32), + .word_size = sizeof(u32), + .reg_read = an8855_efuse_read, + }; + struct device *dev = &pdev->dev; + struct nvmem_device *nvmem; + + /* Assign NVMEM priv to MFD regmap */ + an8855_nvmem_config.priv = dev_get_regmap(dev->parent, "switch"); + an8855_nvmem_config.dev = dev; + nvmem = devm_nvmem_register(dev, &an8855_nvmem_config); + + return PTR_ERR_OR_ZERO(nvmem); +} + +static const struct of_device_id an8855_efuse_of_match[] = { + { .compatible = "airoha,an8855-efuse", }, + { /* sentinel */ } +}; +MODULE_DEVICE_TABLE(of, an8855_efuse_of_match); + +static struct platform_driver an8855_efuse_driver = { + .probe = an8855_efuse_probe, + .driver = { + .name = "an8855-efuse", + .of_match_table = an8855_efuse_of_match, + }, +}; +module_platform_driver(an8855_efuse_driver); + +MODULE_AUTHOR("Christian Marangi <ansuelsmth@gmail.com>"); +MODULE_DESCRIPTION("Driver for AN8855 Switch EFUSE"); +MODULE_LICENSE("GPL");
--
2.48.1