Files
android/drivers/reset/reset-stm32.c
threeeye bc1d038eac REVVL 6 Pro kernel bring-up: full working tree snapshot (2026-09-12)
Squashed backup commit (no shallow-clone history issues) of
xiaomi-mt6833-dev/kernel_xiaomi_mt6833 (lineage-23.2 branch, upstream
commit 9eece662e) plus all fixes applied to get everpal_defconfig building
clean against a modern (GCC 15.2.0) toolchain -- see the previous commit
message on the lineage-23.2 branch (also in this repo history is not
available here since this is a squashed snapshot; full incremental history
lives in the local DL380 checkout and the upstream GitHub remote).

Upstream: https://github.com/xiaomi-mt6833-dev/kernel_xiaomi_mt6833 (lineage-23.2)
2026-09-12 13:36:46 +00:00

109 lines
2.6 KiB
C

/*
* Copyright (C) Maxime Coquelin 2015
* Author: Maxime Coquelin <mcoquelin.stm32@gmail.com>
* License terms: GNU General Public License (GPL), version 2
*
* Heavily based on sunxi driver from Maxime Ripard.
*/
#include <linux/err.h>
#include <linux/io.h>
#include <linux/of.h>
#include <linux/of_address.h>
#include <linux/platform_device.h>
#include <linux/reset-controller.h>
#include <linux/slab.h>
#include <linux/spinlock.h>
#include <linux/types.h>
struct stm32_reset_data {
spinlock_t lock;
void __iomem *membase;
struct reset_controller_dev rcdev;
};
static int stm32_reset_assert(struct reset_controller_dev *rcdev,
unsigned long id)
{
struct stm32_reset_data *data = container_of(rcdev,
struct stm32_reset_data,
rcdev);
int bank = id / BITS_PER_LONG;
int offset = id % BITS_PER_LONG;
unsigned long flags;
u32 reg;
spin_lock_irqsave(&data->lock, flags);
reg = readl(data->membase + (bank * 4));
writel(reg | BIT(offset), data->membase + (bank * 4));
spin_unlock_irqrestore(&data->lock, flags);
return 0;
}
static int stm32_reset_deassert(struct reset_controller_dev *rcdev,
unsigned long id)
{
struct stm32_reset_data *data = container_of(rcdev,
struct stm32_reset_data,
rcdev);
int bank = id / BITS_PER_LONG;
int offset = id % BITS_PER_LONG;
unsigned long flags;
u32 reg;
spin_lock_irqsave(&data->lock, flags);
reg = readl(data->membase + (bank * 4));
writel(reg & ~BIT(offset), data->membase + (bank * 4));
spin_unlock_irqrestore(&data->lock, flags);
return 0;
}
static const struct reset_control_ops stm32_reset_ops = {
.assert = stm32_reset_assert,
.deassert = stm32_reset_deassert,
};
static const struct of_device_id stm32_reset_dt_ids[] = {
{ .compatible = "st,stm32-rcc", },
{ /* sentinel */ },
};
static int stm32_reset_probe(struct platform_device *pdev)
{
struct stm32_reset_data *data;
struct resource *res;
data = devm_kzalloc(&pdev->dev, sizeof(*data), GFP_KERNEL);
if (!data)
return -ENOMEM;
res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
data->membase = devm_ioremap_resource(&pdev->dev, res);
if (IS_ERR(data->membase))
return PTR_ERR(data->membase);
spin_lock_init(&data->lock);
data->rcdev.owner = THIS_MODULE;
data->rcdev.nr_resets = resource_size(res) * 8;
data->rcdev.ops = &stm32_reset_ops;
data->rcdev.of_node = pdev->dev.of_node;
return devm_reset_controller_register(&pdev->dev, &data->rcdev);
}
static struct platform_driver stm32_reset_driver = {
.probe = stm32_reset_probe,
.driver = {
.name = "stm32-rcc-reset",
.of_match_table = stm32_reset_dt_ids,
},
};
builtin_platform_driver(stm32_reset_driver);