Orange Pi5 kernel

^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  1) // SPDX-License-Identifier: GPL-2.0-only
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  2) /*
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  3)  * sfr.c - driver for special function registers
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  4)  *
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  5)  * Copyright (C) 2019 Bootlin.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  6)  *
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  7)  */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  8) #include <linux/mfd/syscon.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  9) #include <linux/module.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 10) #include <linux/nvmem-provider.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 11) #include <linux/random.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 12) #include <linux/of.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 13) #include <linux/of_device.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 14) #include <linux/platform_device.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 15) #include <linux/regmap.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 16) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 17) #define SFR_SN0		0x4c
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 18) #define SFR_SN_SIZE	8
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 19) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 20) struct atmel_sfr_priv {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 21) 	struct regmap			*regmap;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 22) };
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 23) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 24) static int atmel_sfr_read(void *context, unsigned int offset,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 25) 			  void *buf, size_t bytes)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 26) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 27) 	struct atmel_sfr_priv *priv = context;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 28) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 29) 	return regmap_bulk_read(priv->regmap, SFR_SN0 + offset,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 30) 				buf, bytes / 4);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 31) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 32) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 33) static struct nvmem_config atmel_sfr_nvmem_config = {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 34) 	.name = "atmel-sfr",
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 35) 	.read_only = true,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 36) 	.word_size = 4,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 37) 	.stride = 4,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 38) 	.size = SFR_SN_SIZE,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 39) 	.reg_read = atmel_sfr_read,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 40) };
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 41) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 42) static int atmel_sfr_probe(struct platform_device *pdev)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 43) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 44) 	struct device *dev = &pdev->dev;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 45) 	struct device_node *np = dev->of_node;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 46) 	struct nvmem_device *nvmem;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 47) 	struct atmel_sfr_priv *priv;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 48) 	u8 sn[SFR_SN_SIZE];
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 49) 	int ret;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 50) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 51) 	priv = devm_kmalloc(dev, sizeof(*priv), GFP_KERNEL);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 52) 	if (!priv)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 53) 		return -ENOMEM;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 54) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 55) 	priv->regmap = syscon_node_to_regmap(np);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 56) 	if (IS_ERR(priv->regmap)) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 57) 		dev_err(dev, "cannot get parent's regmap\n");
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 58) 		return PTR_ERR(priv->regmap);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 59) 	}
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 60) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 61) 	atmel_sfr_nvmem_config.dev = dev;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 62) 	atmel_sfr_nvmem_config.priv = priv;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 63) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 64) 	nvmem = devm_nvmem_register(dev, &atmel_sfr_nvmem_config);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 65) 	if (IS_ERR(nvmem)) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 66) 		dev_err(dev, "error registering nvmem config\n");
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 67) 		return PTR_ERR(nvmem);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 68) 	}
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 69) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 70) 	ret = atmel_sfr_read(priv, 0, sn, SFR_SN_SIZE);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 71) 	if (ret == 0)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 72) 		add_device_randomness(sn, SFR_SN_SIZE);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 73) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 74) 	return ret;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 75) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 76) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 77) static const struct of_device_id atmel_sfr_dt_ids[] = {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 78) 	{
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 79) 		.compatible = "atmel,sama5d2-sfr",
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 80) 	}, {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 81) 		.compatible = "atmel,sama5d4-sfr",
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 82) 	}, {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 83) 		/* sentinel */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 84) 	},
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 85) };
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 86) MODULE_DEVICE_TABLE(of, atmel_sfr_dt_ids);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 87) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 88) static struct platform_driver atmel_sfr_driver = {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 89) 	.probe = atmel_sfr_probe,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 90) 	.driver = {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 91) 		.name = "atmel-sfr",
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 92) 		.of_match_table = atmel_sfr_dt_ids,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 93) 	},
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 94) };
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 95) module_platform_driver(atmel_sfr_driver);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 96) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 97) MODULE_AUTHOR("Kamel Bouhara <kamel.bouhara@bootlin.com>");
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 98) MODULE_DESCRIPTION("Atmel SFR SN driver for SAMA5D2/4 SoC family");
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 99) MODULE_LICENSE("GPL v2");