1 // SPDX-License-Identifier: GPL-2.0-only
3 * Amlogic Meson GX eFuse Driver
5 * Copyright (c) 2016 Endless Computers, Inc.
6 * Author: Carlo Caione <carlo@endlessm.com>
10 #include <linux/module.h>
11 #include <linux/nvmem-provider.h>
13 #include <linux/platform_device.h>
15 #include <linux/firmware/meson/meson_sm.h>
17 static int meson_efuse_read(void *context
, unsigned int offset
,
18 void *val
, size_t bytes
)
20 return meson_sm_call_read((u8
*)val
, bytes
, SM_EFUSE_READ
, offset
,
24 static int meson_efuse_write(void *context
, unsigned int offset
,
25 void *val
, size_t bytes
)
27 return meson_sm_call_write((u8
*)val
, bytes
, SM_EFUSE_WRITE
, offset
,
31 static const struct of_device_id meson_efuse_match
[] = {
32 { .compatible
= "amlogic,meson-gxbb-efuse", },
35 MODULE_DEVICE_TABLE(of
, meson_efuse_match
);
37 static int meson_efuse_probe(struct platform_device
*pdev
)
39 struct device
*dev
= &pdev
->dev
;
40 struct nvmem_device
*nvmem
;
41 struct nvmem_config
*econfig
;
46 clk
= devm_clk_get(dev
, NULL
);
49 if (ret
!= -EPROBE_DEFER
)
50 dev_err(dev
, "failed to get efuse gate");
54 ret
= clk_prepare_enable(clk
);
56 dev_err(dev
, "failed to enable gate");
60 ret
= devm_add_action_or_reset(dev
,
61 (void(*)(void *))clk_disable_unprepare
,
64 dev_err(dev
, "failed to add disable callback");
68 if (meson_sm_call(SM_EFUSE_USER_MAX
, &size
, 0, 0, 0, 0, 0) < 0) {
69 dev_err(dev
, "failed to get max user");
73 econfig
= devm_kzalloc(dev
, sizeof(*econfig
), GFP_KERNEL
);
78 econfig
->name
= dev_name(dev
);
80 econfig
->word_size
= 1;
81 econfig
->reg_read
= meson_efuse_read
;
82 econfig
->reg_write
= meson_efuse_write
;
85 nvmem
= devm_nvmem_register(&pdev
->dev
, econfig
);
87 return PTR_ERR_OR_ZERO(nvmem
);
90 static struct platform_driver meson_efuse_driver
= {
91 .probe
= meson_efuse_probe
,
93 .name
= "meson-efuse",
94 .of_match_table
= meson_efuse_match
,
98 module_platform_driver(meson_efuse_driver
);
100 MODULE_AUTHOR("Carlo Caione <carlo@endlessm.com>");
101 MODULE_DESCRIPTION("Amlogic Meson GX NVMEM driver");
102 MODULE_LICENSE("GPL v2");