drivers/reset/reset-uniphier-glue.c

0001 // SPDX-License-Identifier: GPL-2.0
0002 //
0003 // reset-uniphier-glue.c - Glue layer reset driver for UniPhier
0004 // Copyright 2018 Socionext Inc.
0005 // Author: Kunihiko Hayashi <hayashi.kunihiko@socionext.com>
0006
0007 #include <linux/clk.h>
0008 #include <linux/module.h>
0009 #include <linux/of_device.h>
0010 #include <linux/platform_device.h>
0011 #include <linux/reset.h>
0012 #include <linux/reset/reset-simple.h>
0013
0014 #define MAX_CLKS    2
0015 #define MAX_RSTS    2
0016
0017 struct uniphier_glue_reset_soc_data {
0018     int nclks;
0019     const char * const *clock_names;
0020     int nrsts;
0021     const char * const *reset_names;
0022 };
0023
0024 struct uniphier_glue_reset_priv {
0025     struct clk_bulk_data clk[MAX_CLKS];
0026     struct reset_control_bulk_data rst[MAX_RSTS];
0027     struct reset_simple_data rdata;
0028     const struct uniphier_glue_reset_soc_data *data;
0029 };
0030
0031 static void uniphier_clk_disable(void *_priv)
0032 {
0033     struct uniphier_glue_reset_priv *priv = _priv;
0034
0035     clk_bulk_disable_unprepare(priv->data->nclks, priv->clk);
0036 }
0037
0038 static void uniphier_rst_assert(void *_priv)
0039 {
0040     struct uniphier_glue_reset_priv *priv = _priv;
0041
0042     reset_control_bulk_assert(priv->data->nrsts, priv->rst);
0043 }
0044
0045 static int uniphier_glue_reset_probe(struct platform_device *pdev)
0046 {
0047     struct device *dev = &pdev->dev;
0048     struct uniphier_glue_reset_priv *priv;
0049     struct resource *res;
0050     resource_size_t size;
0051     int i, ret;
0052
0053     priv = devm_kzalloc(dev, sizeof(*priv), GFP_KERNEL);
0054     if (!priv)
0055         return -ENOMEM;
0056
0057     priv->data = of_device_get_match_data(dev);
0058     if (WARN_ON(!priv->data || priv->data->nclks > MAX_CLKS ||
0059             priv->data->nrsts > MAX_RSTS))
0060         return -EINVAL;
0061
0062     res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
0063     size = resource_size(res);
0064     priv->rdata.membase = devm_ioremap_resource(dev, res);
0065     if (IS_ERR(priv->rdata.membase))
0066         return PTR_ERR(priv->rdata.membase);
0067
0068     for (i = 0; i < priv->data->nclks; i++)
0069         priv->clk[i].id = priv->data->clock_names[i];
0070     ret = devm_clk_bulk_get(dev, priv->data->nclks, priv->clk);
0071     if (ret)
0072         return ret;
0073
0074     for (i = 0; i < priv->data->nrsts; i++)
0075         priv->rst[i].id = priv->data->reset_names[i];
0076     ret = devm_reset_control_bulk_get_shared(dev, priv->data->nrsts,
0077                          priv->rst);
0078     if (ret)
0079         return ret;
0080
0081     ret = clk_bulk_prepare_enable(priv->data->nclks, priv->clk);
0082     if (ret)
0083         return ret;
0084
0085     ret = devm_add_action_or_reset(dev, uniphier_clk_disable, priv);
0086     if (ret)
0087         return ret;
0088
0089     ret = reset_control_bulk_deassert(priv->data->nrsts, priv->rst);
0090     if (ret)
0091         return ret;
0092
0093     ret = devm_add_action_or_reset(dev, uniphier_rst_assert, priv);
0094     if (ret)
0095         return ret;
0096
0097     spin_lock_init(&priv->rdata.lock);
0098     priv->rdata.rcdev.owner = THIS_MODULE;
0099     priv->rdata.rcdev.nr_resets = size * BITS_PER_BYTE;
0100     priv->rdata.rcdev.ops = &reset_simple_ops;
0101     priv->rdata.rcdev.of_node = dev->of_node;
0102     priv->rdata.active_low = true;
0103
0104     platform_set_drvdata(pdev, priv);
0105
0106     return devm_reset_controller_register(dev, &priv->rdata.rcdev);
0107 }
0108
0109 static const char * const uniphier_pro4_clock_reset_names[] = {
0110     "gio", "link",
0111 };
0112
0113 static const struct uniphier_glue_reset_soc_data uniphier_pro4_data = {
0114     .nclks = ARRAY_SIZE(uniphier_pro4_clock_reset_names),
0115     .clock_names = uniphier_pro4_clock_reset_names,
0116     .nrsts = ARRAY_SIZE(uniphier_pro4_clock_reset_names),
0117     .reset_names = uniphier_pro4_clock_reset_names,
0118 };
0119
0120 static const char * const uniphier_pxs2_clock_reset_names[] = {
0121     "link",
0122 };
0123
0124 static const struct uniphier_glue_reset_soc_data uniphier_pxs2_data = {
0125     .nclks = ARRAY_SIZE(uniphier_pxs2_clock_reset_names),
0126     .clock_names = uniphier_pxs2_clock_reset_names,
0127     .nrsts = ARRAY_SIZE(uniphier_pxs2_clock_reset_names),
0128     .reset_names = uniphier_pxs2_clock_reset_names,
0129 };
0130
0131 static const struct of_device_id uniphier_glue_reset_match[] = {
0132     {
0133         .compatible = "socionext,uniphier-pro4-usb3-reset",
0134         .data = &uniphier_pro4_data,
0135     },
0136     {
0137         .compatible = "socionext,uniphier-pro5-usb3-reset",
0138         .data = &uniphier_pro4_data,
0139     },
0140     {
0141         .compatible = "socionext,uniphier-pxs2-usb3-reset",
0142         .data = &uniphier_pxs2_data,
0143     },
0144     {
0145         .compatible = "socionext,uniphier-ld20-usb3-reset",
0146         .data = &uniphier_pxs2_data,
0147     },
0148     {
0149         .compatible = "socionext,uniphier-pxs3-usb3-reset",
0150         .data = &uniphier_pxs2_data,
0151     },
0152     {
0153         .compatible = "socionext,uniphier-nx1-usb3-reset",
0154         .data = &uniphier_pxs2_data,
0155     },
0156     {
0157         .compatible = "socionext,uniphier-pro4-ahci-reset",
0158         .data = &uniphier_pro4_data,
0159     },
0160     {
0161         .compatible = "socionext,uniphier-pxs2-ahci-reset",
0162         .data = &uniphier_pxs2_data,
0163     },
0164     {
0165         .compatible = "socionext,uniphier-pxs3-ahci-reset",
0166         .data = &uniphier_pxs2_data,
0167     },
0168     { /* Sentinel */ }
0169 };
0170 MODULE_DEVICE_TABLE(of, uniphier_glue_reset_match);
0171
0172 static struct platform_driver uniphier_glue_reset_driver = {
0173     .probe = uniphier_glue_reset_probe,
0174     .driver = {
0175         .name = "uniphier-glue-reset",
0176         .of_match_table = uniphier_glue_reset_match,
0177     },
0178 };
0179 module_platform_driver(uniphier_glue_reset_driver);
0180
0181 MODULE_AUTHOR("Kunihiko Hayashi <hayashi.kunihiko@socionext.com>");
0182 MODULE_DESCRIPTION("UniPhier Glue layer reset driver");
0183 MODULE_LICENSE("GPL");