Commit 499fef09 authored by Kunihiko Hayashi's avatar Kunihiko Hayashi Committed by Philipp Zabel
Browse files

reset: uniphier: add USB3 core reset control 



Add a reset line to enable USB3 core implemented in UniPhier SoCs.

This reuses only the reset operations in reset-simple, because
the reset-simple doesn't handle any SoC-dependent clocks and resets.
This reset line is included in the USB3 glue layer, and it's necessary
to enable clocks and deassert resets of the layer before using this
reset line.

Signed-off-by: default avatarKunihiko Hayashi <hayashi.kunihiko@socionext.com>
Signed-off-by: default avatarPhilipp Zabel <p.zabel@pengutronix.de>
parent ef8b023b

drivers/reset/Kconfig

+10 −0
Original line number Diff line number Diff line
@@ -147,6 +147,16 @@ config RESET_UNIPHIER 
	  Say Y if you want to control reset signals provided by System Control

	  block, Media I/O block, Peripheral Block.



config RESET_UNIPHIER_USB3

	tristate "USB3 reset driver for UniPhier SoCs"

	depends on (ARCH_UNIPHIER || COMPILE_TEST) && OF

	default ARCH_UNIPHIER

	select RESET_SIMPLE

	help

	  Support for the USB3 core reset on UniPhier SoCs.

	  Say Y if you want to control reset signals provided by

	  USB3 glue layer.



config RESET_ZYNQ

	bool "ZYNQ Reset Driver" if COMPILE_TEST

	default ARCH_ZYNQ

drivers/reset/Makefile

+1 −0
Original line number Diff line number Diff line
@@ -21,5 +21,6 @@ obj-$(CONFIG_RESET_SUNXI) += reset-sunxi.o 
obj-$(CONFIG_RESET_TI_SCI) += reset-ti-sci.o

obj-$(CONFIG_RESET_TI_SYSCON) += reset-ti-syscon.o

obj-$(CONFIG_RESET_UNIPHIER) += reset-uniphier.o

obj-$(CONFIG_RESET_UNIPHIER_USB3) += reset-uniphier-usb3.o

obj-$(CONFIG_RESET_ZYNQ) += reset-zynq.o

drivers/reset/reset-uniphier-usb3.c

0 → 100644
+171 −0
Original line number Diff line number Diff line 
// 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");

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