linux/drivers/reset/reset-uniphier-usb3.c

172 lines
4.4 KiB
C

// SPDX-License-Identifier: GPL-2.0
//
// reset-uniphier-usb3.c - USB3 reset driver for UniPhier
// Copyright 2018 Socionext Inc.
// Author: Kunihiko Hayashi <hayashi.kunihiko@socionext.com>
#include <linux/clk.h>
#include <linux/module.h>
#include <linux/of_device.h>
#include <linux/platform_device.h>
#include <linux/reset.h>
#include "reset-simple.h"
#define MAX_CLKS 2
#define MAX_RSTS 2
struct uniphier_usb3_reset_soc_data {
int nclks;
const char * const *clock_names;
int nrsts;
const char * const *reset_names;
};
struct uniphier_usb3_reset_priv {
struct clk_bulk_data clk[MAX_CLKS];
struct reset_control *rst[MAX_RSTS];
struct reset_simple_data rdata;
const struct uniphier_usb3_reset_soc_data *data;
};
static int uniphier_usb3_reset_probe(struct platform_device *pdev)
{
struct device *dev = &pdev->dev;
struct uniphier_usb3_reset_priv *priv;
struct resource *res;
resource_size_t size;
const char *name;
int i, ret, nr;
priv = devm_kzalloc(dev, sizeof(*priv), GFP_KERNEL);
if (!priv)
return -ENOMEM;
priv->data = of_device_get_match_data(dev);
if (WARN_ON(!priv->data || priv->data->nclks > MAX_CLKS ||
priv->data->nrsts > MAX_RSTS))
return -EINVAL;
res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
size = resource_size(res);
priv->rdata.membase = devm_ioremap_resource(dev, res);
if (IS_ERR(priv->rdata.membase))
return PTR_ERR(priv->rdata.membase);
for (i = 0; i < priv->data->nclks; i++)
priv->clk[i].id = priv->data->clock_names[i];
ret = devm_clk_bulk_get(dev, priv->data->nclks, priv->clk);
if (ret)
return ret;
for (i = 0; i < priv->data->nrsts; i++) {
name = priv->data->reset_names[i];
priv->rst[i] = devm_reset_control_get_shared(dev, name);
if (IS_ERR(priv->rst[i]))
return PTR_ERR(priv->rst[i]);
}
ret = clk_bulk_prepare_enable(priv->data->nclks, priv->clk);
if (ret)
return ret;
for (nr = 0; nr < priv->data->nrsts; nr++) {
ret = reset_control_deassert(priv->rst[nr]);
if (ret)
goto out_rst_assert;
}
spin_lock_init(&priv->rdata.lock);
priv->rdata.rcdev.owner = THIS_MODULE;
priv->rdata.rcdev.nr_resets = size * BITS_PER_BYTE;
priv->rdata.rcdev.ops = &reset_simple_ops;
priv->rdata.rcdev.of_node = dev->of_node;
priv->rdata.active_low = true;
platform_set_drvdata(pdev, priv);
ret = devm_reset_controller_register(dev, &priv->rdata.rcdev);
if (ret)
goto out_rst_assert;
return 0;
out_rst_assert:
while (nr--)
reset_control_assert(priv->rst[nr]);
clk_bulk_disable_unprepare(priv->data->nclks, priv->clk);
return ret;
}
static int uniphier_usb3_reset_remove(struct platform_device *pdev)
{
struct uniphier_usb3_reset_priv *priv = platform_get_drvdata(pdev);
int i;
for (i = 0; i < priv->data->nrsts; i++)
reset_control_assert(priv->rst[i]);
clk_bulk_disable_unprepare(priv->data->nclks, priv->clk);
return 0;
}
static const char * const uniphier_pro4_clock_reset_names[] = {
"gio", "link",
};
static const struct uniphier_usb3_reset_soc_data uniphier_pro4_data = {
.nclks = ARRAY_SIZE(uniphier_pro4_clock_reset_names),
.clock_names = uniphier_pro4_clock_reset_names,
.nrsts = ARRAY_SIZE(uniphier_pro4_clock_reset_names),
.reset_names = uniphier_pro4_clock_reset_names,
};
static const char * const uniphier_pxs2_clock_reset_names[] = {
"link",
};
static const struct uniphier_usb3_reset_soc_data uniphier_pxs2_data = {
.nclks = ARRAY_SIZE(uniphier_pxs2_clock_reset_names),
.clock_names = uniphier_pxs2_clock_reset_names,
.nrsts = ARRAY_SIZE(uniphier_pxs2_clock_reset_names),
.reset_names = uniphier_pxs2_clock_reset_names,
};
static const struct of_device_id uniphier_usb3_reset_match[] = {
{
.compatible = "socionext,uniphier-pro4-usb3-reset",
.data = &uniphier_pro4_data,
},
{
.compatible = "socionext,uniphier-pxs2-usb3-reset",
.data = &uniphier_pxs2_data,
},
{
.compatible = "socionext,uniphier-ld20-usb3-reset",
.data = &uniphier_pxs2_data,
},
{
.compatible = "socionext,uniphier-pxs3-usb3-reset",
.data = &uniphier_pxs2_data,
},
{ /* Sentinel */ }
};
MODULE_DEVICE_TABLE(of, uniphier_usb3_reset_match);
static struct platform_driver uniphier_usb3_reset_driver = {
.probe = uniphier_usb3_reset_probe,
.remove = uniphier_usb3_reset_remove,
.driver = {
.name = "uniphier-usb3-reset",
.of_match_table = uniphier_usb3_reset_match,
},
};
module_platform_driver(uniphier_usb3_reset_driver);
MODULE_AUTHOR("Kunihiko Hayashi <hayashi.kunihiko@socionext.com>");
MODULE_DESCRIPTION("UniPhier USB3 Reset Driver");
MODULE_LICENSE("GPL");