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authorKunihiko Hayashi <hayashi.kunihiko@socionext.com>2018-07-10 10:14:17 +0900
committerPhilipp Zabel <p.zabel@pengutronix.de>2018-07-16 12:15:55 +0200
commit499fef09a3237497906084da3eede0185fc9abb8 (patch)
tree22b2a3dbed0be058e66e3c26c97501c90b049fa8 /drivers
parentef8b023b230bfa3cf1f09ea1b8f1e47e37b389f2 (diff)
downloadlinux-499fef09a3237497906084da3eede0185fc9abb8.tar.bz2
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: Kunihiko Hayashi <hayashi.kunihiko@socionext.com> Signed-off-by: Philipp Zabel <p.zabel@pengutronix.de>
Diffstat (limited to 'drivers')
-rw-r--r--drivers/reset/Kconfig10
-rw-r--r--drivers/reset/Makefile1
-rw-r--r--drivers/reset/reset-uniphier-usb3.c171
3 files changed, 182 insertions, 0 deletions
diff --git a/drivers/reset/Kconfig b/drivers/reset/Kconfig
index 756ad2b27d0f..a70262cb7e56 100644
--- a/drivers/reset/Kconfig
+++ b/drivers/reset/Kconfig
@@ -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
diff --git a/drivers/reset/Makefile b/drivers/reset/Makefile
index 6881e4d287f0..0676b6b1976f 100644
--- a/drivers/reset/Makefile
+++ b/drivers/reset/Makefile
@@ -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
diff --git a/drivers/reset/reset-uniphier-usb3.c b/drivers/reset/reset-uniphier-usb3.c
new file mode 100644
index 000000000000..ffa1b19b594d
--- /dev/null
+++ b/drivers/reset/reset-uniphier-usb3.c
@@ -0,0 +1,171 @@
+// 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");