diff options
Diffstat (limited to 'drivers/reset/reset-uniphier-usb3.c')
| -rw-r--r-- | drivers/reset/reset-uniphier-usb3.c | 171 |
1 files changed, 171 insertions, 0 deletions
diff --git a/drivers/reset/reset-uniphier-usb3.c b/drivers/reset/reset-uniphier-usb3.c new file mode 100644 index 000000000..ffa1b19b5 --- /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"); |