1 // SPDX-License-Identifier: GPL-2.0
7 #include <linux/device.h>
8 #include <linux/firmware/imx/sci.h>
9 #include <linux/init.h>
10 #include <linux/input.h>
11 #include <linux/interrupt.h>
12 #include <linux/jiffies.h>
13 #include <linux/kernel.h>
14 #include <linux/module.h>
16 #include <linux/platform_device.h>
17 #include <linux/property.h>
19 #define DEBOUNCE_TIME 30
20 #define REPEAT_INTERVAL 60
22 #define SC_IRQ_BUTTON 1
23 #define SC_IRQ_GROUP_WAKE 3
25 #define IMX_SC_MISC_FUNC_GET_BUTTON_STATUS 18
27 struct imx_key_drv_data {
29 bool keystate; /* true: pressed, false: released */
30 struct delayed_work check_work;
31 struct input_dev *input;
32 struct imx_sc_ipc *key_ipc_handle;
33 struct notifier_block key_notifier;
36 struct imx_sc_msg_key {
37 struct imx_sc_rpc_msg hdr;
41 static int imx_sc_key_notify(struct notifier_block *nb,
42 unsigned long event, void *group)
44 struct imx_key_drv_data *priv =
46 struct imx_key_drv_data,
49 if ((event & SC_IRQ_BUTTON) && (*(u8 *)group == SC_IRQ_GROUP_WAKE)) {
50 schedule_delayed_work(&priv->check_work,
51 msecs_to_jiffies(DEBOUNCE_TIME));
52 pm_wakeup_event(priv->input->dev.parent, 0);
58 static void imx_sc_check_for_events(struct work_struct *work)
60 struct imx_key_drv_data *priv =
62 struct imx_key_drv_data,
64 struct input_dev *input = priv->input;
65 struct imx_sc_msg_key msg;
66 struct imx_sc_rpc_msg *hdr = &msg.hdr;
70 hdr->ver = IMX_SC_RPC_VERSION;
71 hdr->svc = IMX_SC_RPC_SVC_MISC;
72 hdr->func = IMX_SC_MISC_FUNC_GET_BUTTON_STATUS;
75 error = imx_scu_call_rpc(priv->key_ipc_handle, &msg, true);
77 dev_err(&input->dev, "read imx sc key failed, error %d\n", error);
82 * The response data from SCU firmware is 4 bytes,
83 * but ONLY the first byte is the key state, other
84 * 3 bytes could be some dirty data, so we should
85 * ONLY take the first byte as key state.
87 state = (bool)(msg.state & 0xff);
89 if (state ^ priv->keystate) {
90 priv->keystate = state;
91 input_event(input, EV_KEY, priv->keycode, state);
94 pm_relax(priv->input->dev.parent);
98 schedule_delayed_work(&priv->check_work,
99 msecs_to_jiffies(REPEAT_INTERVAL));
102 static int imx_sc_key_probe(struct platform_device *pdev)
104 struct imx_key_drv_data *priv;
105 struct input_dev *input;
108 priv = devm_kzalloc(&pdev->dev, sizeof(*priv), GFP_KERNEL);
112 error = imx_scu_get_handle(&priv->key_ipc_handle);
116 if (device_property_read_u32(&pdev->dev, "linux,keycodes",
118 dev_err(&pdev->dev, "missing linux,keycodes property\n");
122 INIT_DELAYED_WORK(&priv->check_work, imx_sc_check_for_events);
124 input = devm_input_allocate_device(&pdev->dev);
126 dev_err(&pdev->dev, "failed to allocate the input device\n");
130 input->name = pdev->name;
131 input->phys = "imx-sc-key/input0";
132 input->id.bustype = BUS_HOST;
134 input_set_capability(input, EV_KEY, priv->keycode);
136 error = input_register_device(input);
138 dev_err(&pdev->dev, "failed to register input device\n");
143 platform_set_drvdata(pdev, priv);
145 error = imx_scu_irq_group_enable(SC_IRQ_GROUP_WAKE, SC_IRQ_BUTTON,
148 dev_err(&pdev->dev, "failed to enable scu group irq\n");
152 priv->key_notifier.notifier_call = imx_sc_key_notify;
153 error = imx_scu_irq_register_notifier(&priv->key_notifier);
155 imx_scu_irq_group_enable(SC_IRQ_GROUP_WAKE, SC_IRQ_BUTTON,
157 dev_err(&pdev->dev, "failed to register scu notifier\n");
164 static int imx_sc_key_remove(struct platform_device *pdev)
166 struct imx_key_drv_data *priv = platform_get_drvdata(pdev);
168 imx_scu_irq_group_enable(SC_IRQ_GROUP_WAKE, SC_IRQ_BUTTON, false);
169 imx_scu_irq_unregister_notifier(&priv->key_notifier);
170 cancel_delayed_work_sync(&priv->check_work);
175 static const struct of_device_id imx_sc_key_ids[] = {
176 { .compatible = "fsl,imx-sc-key" },
179 MODULE_DEVICE_TABLE(of, imx_sc_key_ids);
181 static struct platform_driver imx_sc_key_driver = {
183 .name = "imx-sc-key",
184 .of_match_table = imx_sc_key_ids,
186 .probe = imx_sc_key_probe,
187 .remove = imx_sc_key_remove,
189 module_platform_driver(imx_sc_key_driver);
191 MODULE_AUTHOR("Anson Huang <Anson.Huang@nxp.com>");
192 MODULE_DESCRIPTION("i.MX System Controller Key Driver");
193 MODULE_LICENSE("GPL v2");