reset-imx-scu.c

  1// SPDX-License-Identifier: GPL-2.0+
  2/*
  3 * Copyright 2025 NXP
  4 * Frank Li <Frank.Li@nxp.com>
  5 */
  6#include <linux/firmware/imx/svc/misc.h>
  7#include <linux/kernel.h>
  8#include <linux/module.h>
  9#include <linux/of.h>
 10#include <linux/platform_device.h>
 11#include <linux/reset-controller.h>
 12
 13#include <dt-bindings/firmware/imx/rsrc.h>
 14
 15struct imx_scu_reset {
 16	struct reset_controller_dev rc;
 17	struct imx_sc_ipc *ipc_handle;
 18};
 19
 20static struct imx_scu_reset *to_imx_scu(struct reset_controller_dev *rc)
 21{
 22	return container_of(rc, struct imx_scu_reset, rc);
 23}
 24
 25struct imx_scu_id_map {
 26	u32 resource_id;
 27	u32 command_id;
 28};
 29
 30static const struct imx_scu_id_map imx_scu_id_map[] = {
 31	{ IMX_SC_R_CSI_0, IMX_SC_C_MIPI_RESET },
 32	{ IMX_SC_R_CSI_1, IMX_SC_C_MIPI_RESET },
 33};
 34
 35static int imx_scu_reset_assert(struct reset_controller_dev *rc, unsigned long id)
 36{
 37	struct imx_scu_reset *priv = to_imx_scu(rc);
 38
 39	return imx_sc_misc_set_control(priv->ipc_handle, imx_scu_id_map[id].resource_id,
 40				       imx_scu_id_map[id].command_id, true);
 41}
 42
 43static const struct reset_control_ops imx_scu_reset_ops = {
 44	.assert = imx_scu_reset_assert,
 45};
 46
 47static int imx_scu_xlate(struct reset_controller_dev *rc, const struct of_phandle_args *reset_spec)
 48{
 49	int i;
 50
 51	for (i = 0; i < rc->nr_resets; i++)
 52		if (reset_spec->args[0] == imx_scu_id_map[i].resource_id)
 53			return i;
 54
 55	return -EINVAL;
 56}
 57
 58static int imx_scu_reset_probe(struct platform_device *pdev)
 59{
 60	struct device *dev = &pdev->dev;
 61	struct imx_scu_reset *priv;
 62	int ret;
 63
 64	priv = devm_kzalloc(dev, sizeof(*priv), GFP_KERNEL);
 65	if (!priv)
 66		return -ENOMEM;
 67
 68	platform_set_drvdata(pdev, &priv->rc);
 69
 70	ret = imx_scu_get_handle(&priv->ipc_handle);
 71	if (ret)
 72		return dev_err_probe(dev, ret, "sc_misc_MIPI get ipc handle failed!\n");
 73
 74	priv->rc.ops = &imx_scu_reset_ops;
 75	priv->rc.owner = THIS_MODULE;
 76	priv->rc.of_node = dev->of_node;
 77	priv->rc.of_reset_n_cells = 1;
 78	priv->rc.of_xlate = imx_scu_xlate;
 79	priv->rc.nr_resets = ARRAY_SIZE(imx_scu_id_map);
 80
 81	return devm_reset_controller_register(dev, &priv->rc);
 82}
 83
 84static const struct of_device_id imx_scu_reset_ids[] = {
 85	{ .compatible = "fsl,imx-scu-reset", },
 86	{}
 87};
 88MODULE_DEVICE_TABLE(of, imx_scu_reset_ids);
 89
 90static struct platform_driver imx_scu_reset_driver = {
 91	.probe          = imx_scu_reset_probe,
 92	.driver = {
 93		.name = "scu-reset",
 94		.of_match_table = imx_scu_reset_ids,
 95	},
 96};
 97module_platform_driver(imx_scu_reset_driver);
 98
 99MODULE_AUTHOR("Frank Li <Frank.Li@nxp.com>");
100MODULE_DESCRIPTION("i.MX scu reset driver");
101MODULE_LICENSE("GPL");