linux-stable/drivers/nvmem/qcom-spmi-sdam.c
Rafał Miłecki 2cc3b37f5b nvmem: add explicit config option to read old syntax fixed OF cells
Binding for fixed NVMEM cells defined directly as NVMEM device subnodes
has been deprecated. It has been replaced by the "fixed-layout" NVMEM
layout binding.

New syntax is meant to be clearer and should help avoiding imprecise
bindings.

NVMEM subsystem already supports the new binding. It should be a good
idea to limit support for old syntax to existing drivers that actually
support & use it (we can't break backward compatibility!). That way we
additionally encourage new bindings & drivers to ignore deprecated
binding.

It wasn't clear (to me) if rtc and w1 code actually uses old syntax
fixed cells. I enabled them to don't risk any breakage.

Signed-off-by: Rafał Miłecki <rafal@milecki.pl>
[for meson-{efuse,mx-efuse}.c]
Acked-by: Martin Blumenstingl <martin.blumenstingl@googlemail.com>
[for mtk-efuse.c, nvmem/core.c, nvmem-provider.h]
Reviewed-by: AngeloGioacchino Del Regno <angelogioacchino.delregno@collabora.com>
[MT8192, MT8195 Chromebooks]
Tested-by: AngeloGioacchino Del Regno <angelogioacchino.delregno@collabora.com>
[for microchip-otpc.c]
Reviewed-by: Claudiu Beznea <claudiu.beznea@microchip.com>
[SAMA7G5-EK]
Tested-by: Claudiu Beznea <claudiu.beznea@microchip.com>
Acked-by: Jernej Skrabec <jernej.skrabec@gmail.com>
Signed-off-by: Srinivas Kandagatla <srinivas.kandagatla@linaro.org>
Link: https://lore.kernel.org/r/20231020105545.216052-3-srinivas.kandagatla@linaro.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2023-10-21 19:19:06 +02:00

182 lines
4.3 KiB
C

// SPDX-License-Identifier: GPL-2.0-only
/*
* Copyright (c) 2017, 2020-2021, The Linux Foundation. All rights reserved.
*/
#include <linux/device.h>
#include <linux/module.h>
#include <linux/of.h>
#include <linux/nvmem-provider.h>
#include <linux/platform_device.h>
#include <linux/regmap.h>
#define SDAM_MEM_START 0x40
#define REGISTER_MAP_ID 0x40
#define REGISTER_MAP_VERSION 0x41
#define SDAM_SIZE 0x44
#define SDAM_PBS_TRIG_SET 0xE5
#define SDAM_PBS_TRIG_CLR 0xE6
struct sdam_chip {
struct regmap *regmap;
struct nvmem_config sdam_config;
unsigned int base;
unsigned int size;
};
/* read only register offsets */
static const u8 sdam_ro_map[] = {
REGISTER_MAP_ID,
REGISTER_MAP_VERSION,
SDAM_SIZE
};
static bool sdam_is_valid(struct sdam_chip *sdam, unsigned int offset,
size_t len)
{
unsigned int sdam_mem_end = SDAM_MEM_START + sdam->size - 1;
if (!len)
return false;
if (offset >= SDAM_MEM_START && offset <= sdam_mem_end
&& (offset + len - 1) <= sdam_mem_end)
return true;
else if ((offset == SDAM_PBS_TRIG_SET || offset == SDAM_PBS_TRIG_CLR)
&& (len == 1))
return true;
return false;
}
static bool sdam_is_ro(unsigned int offset, size_t len)
{
int i;
for (i = 0; i < ARRAY_SIZE(sdam_ro_map); i++)
if (offset <= sdam_ro_map[i] && (offset + len) > sdam_ro_map[i])
return true;
return false;
}
static int sdam_read(void *priv, unsigned int offset, void *val,
size_t bytes)
{
struct sdam_chip *sdam = priv;
struct device *dev = sdam->sdam_config.dev;
int rc;
if (!sdam_is_valid(sdam, offset, bytes)) {
dev_err(dev, "Invalid SDAM offset %#x len=%zd\n",
offset, bytes);
return -EINVAL;
}
rc = regmap_bulk_read(sdam->regmap, sdam->base + offset, val, bytes);
if (rc < 0)
dev_err(dev, "Failed to read SDAM offset %#x len=%zd, rc=%d\n",
offset, bytes, rc);
return rc;
}
static int sdam_write(void *priv, unsigned int offset, void *val,
size_t bytes)
{
struct sdam_chip *sdam = priv;
struct device *dev = sdam->sdam_config.dev;
int rc;
if (!sdam_is_valid(sdam, offset, bytes)) {
dev_err(dev, "Invalid SDAM offset %#x len=%zd\n",
offset, bytes);
return -EINVAL;
}
if (sdam_is_ro(offset, bytes)) {
dev_err(dev, "Invalid write offset %#x len=%zd\n",
offset, bytes);
return -EINVAL;
}
rc = regmap_bulk_write(sdam->regmap, sdam->base + offset, val, bytes);
if (rc < 0)
dev_err(dev, "Failed to write SDAM offset %#x len=%zd, rc=%d\n",
offset, bytes, rc);
return rc;
}
static int sdam_probe(struct platform_device *pdev)
{
struct sdam_chip *sdam;
struct nvmem_device *nvmem;
unsigned int val;
int rc;
sdam = devm_kzalloc(&pdev->dev, sizeof(*sdam), GFP_KERNEL);
if (!sdam)
return -ENOMEM;
sdam->regmap = dev_get_regmap(pdev->dev.parent, NULL);
if (!sdam->regmap) {
dev_err(&pdev->dev, "Failed to get regmap handle\n");
return -ENXIO;
}
rc = of_property_read_u32(pdev->dev.of_node, "reg", &sdam->base);
if (rc < 0) {
dev_err(&pdev->dev, "Failed to get SDAM base, rc=%d\n", rc);
return -EINVAL;
}
rc = regmap_read(sdam->regmap, sdam->base + SDAM_SIZE, &val);
if (rc < 0) {
dev_err(&pdev->dev, "Failed to read SDAM_SIZE rc=%d\n", rc);
return -EINVAL;
}
sdam->size = val * 32;
sdam->sdam_config.dev = &pdev->dev;
sdam->sdam_config.name = "spmi_sdam";
sdam->sdam_config.id = NVMEM_DEVID_AUTO;
sdam->sdam_config.owner = THIS_MODULE;
sdam->sdam_config.add_legacy_fixed_of_cells = true;
sdam->sdam_config.stride = 1;
sdam->sdam_config.word_size = 1;
sdam->sdam_config.reg_read = sdam_read;
sdam->sdam_config.reg_write = sdam_write;
sdam->sdam_config.priv = sdam;
nvmem = devm_nvmem_register(&pdev->dev, &sdam->sdam_config);
if (IS_ERR(nvmem)) {
dev_err(&pdev->dev,
"Failed to register SDAM nvmem device rc=%ld\n",
PTR_ERR(nvmem));
return -ENXIO;
}
dev_dbg(&pdev->dev,
"SDAM base=%#x size=%u registered successfully\n",
sdam->base, sdam->size);
return 0;
}
static const struct of_device_id sdam_match_table[] = {
{ .compatible = "qcom,spmi-sdam" },
{},
};
MODULE_DEVICE_TABLE(of, sdam_match_table);
static struct platform_driver sdam_driver = {
.driver = {
.name = "qcom,spmi-sdam",
.of_match_table = sdam_match_table,
},
.probe = sdam_probe,
};
module_platform_driver(sdam_driver);
MODULE_DESCRIPTION("QCOM SPMI SDAM driver");
MODULE_LICENSE("GPL v2");