linux/drivers/reset/reset-brcmstb.c
Florian Fainelli ce89d8d3a7 reset: brcmstb: Remove resource checks
The use of IS_ALIGNED() is incorrect, the typical resource we pass looks
like this: start: 0x8404318, size: 0x30. When using IS_ALIGNED() we will
get the following 0x8404318 & (0x18 - 1) = 0x10 which is definitively
not equal to 0, same goes with the size. These two checks would make the
driver fail probing.

Remove the resource checks, since there should be no constraint on the
base addresse or size.

Fixes: 77750bc089 ("reset: Add Broadcom STB SW_INIT reset controller driver")
Signed-off-by: Florian Fainelli <f.fainelli@gmail.com>
Signed-off-by: Philipp Zabel <p.zabel@pengutronix.de>
2019-12-10 11:43:37 +01:00

127 lines
3.3 KiB
C

// SPDX-License-Identifier: GPL-2.0
/*
* Broadcom STB generic reset controller for SW_INIT style reset controller
*
* Author: Florian Fainelli <f.fainelli@gmail.com>
* Copyright (C) 2018 Broadcom
*/
#include <linux/delay.h>
#include <linux/device.h>
#include <linux/io.h>
#include <linux/module.h>
#include <linux/of.h>
#include <linux/platform_device.h>
#include <linux/reset-controller.h>
#include <linux/types.h>
struct brcmstb_reset {
void __iomem *base;
struct reset_controller_dev rcdev;
};
#define SW_INIT_SET 0x00
#define SW_INIT_CLEAR 0x04
#define SW_INIT_STATUS 0x08
#define SW_INIT_BIT(id) BIT((id) & 0x1f)
#define SW_INIT_BANK(id) ((id) >> 5)
/* A full bank contains extra registers that we are not utilizing but still
* qualify as a single bank.
*/
#define SW_INIT_BANK_SIZE 0x18
static inline
struct brcmstb_reset *to_brcmstb(struct reset_controller_dev *rcdev)
{
return container_of(rcdev, struct brcmstb_reset, rcdev);
}
static int brcmstb_reset_assert(struct reset_controller_dev *rcdev,
unsigned long id)
{
unsigned int off = SW_INIT_BANK(id) * SW_INIT_BANK_SIZE;
struct brcmstb_reset *priv = to_brcmstb(rcdev);
writel_relaxed(SW_INIT_BIT(id), priv->base + off + SW_INIT_SET);
return 0;
}
static int brcmstb_reset_deassert(struct reset_controller_dev *rcdev,
unsigned long id)
{
unsigned int off = SW_INIT_BANK(id) * SW_INIT_BANK_SIZE;
struct brcmstb_reset *priv = to_brcmstb(rcdev);
writel_relaxed(SW_INIT_BIT(id), priv->base + off + SW_INIT_CLEAR);
/* Maximum reset delay after de-asserting a line and seeing block
* operation is typically 14us for the worst case, build some slack
* here.
*/
usleep_range(100, 200);
return 0;
}
static int brcmstb_reset_status(struct reset_controller_dev *rcdev,
unsigned long id)
{
unsigned int off = SW_INIT_BANK(id) * SW_INIT_BANK_SIZE;
struct brcmstb_reset *priv = to_brcmstb(rcdev);
return readl_relaxed(priv->base + off + SW_INIT_STATUS) &
SW_INIT_BIT(id);
}
static const struct reset_control_ops brcmstb_reset_ops = {
.assert = brcmstb_reset_assert,
.deassert = brcmstb_reset_deassert,
.status = brcmstb_reset_status,
};
static int brcmstb_reset_probe(struct platform_device *pdev)
{
struct device *kdev = &pdev->dev;
struct brcmstb_reset *priv;
struct resource *res;
priv = devm_kzalloc(kdev, sizeof(*priv), GFP_KERNEL);
if (!priv)
return -ENOMEM;
res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
priv->base = devm_ioremap_resource(kdev, res);
if (IS_ERR(priv->base))
return PTR_ERR(priv->base);
dev_set_drvdata(kdev, priv);
priv->rcdev.owner = THIS_MODULE;
priv->rcdev.nr_resets = DIV_ROUND_DOWN_ULL(resource_size(res),
SW_INIT_BANK_SIZE) * 32;
priv->rcdev.ops = &brcmstb_reset_ops;
priv->rcdev.of_node = kdev->of_node;
/* Use defaults: 1 cell and simple xlate function */
return devm_reset_controller_register(kdev, &priv->rcdev);
}
static const struct of_device_id brcmstb_reset_of_match[] = {
{ .compatible = "brcm,brcmstb-reset" },
{ /* sentinel */ }
};
static struct platform_driver brcmstb_reset_driver = {
.probe = brcmstb_reset_probe,
.driver = {
.name = "brcmstb-reset",
.of_match_table = brcmstb_reset_of_match,
},
};
module_platform_driver(brcmstb_reset_driver);
MODULE_AUTHOR("Broadcom");
MODULE_DESCRIPTION("Broadcom STB reset controller");
MODULE_LICENSE("GPL");