On Mon, Sep 16, 2019 at 10:52:50AM +0800, Anson Huang wrote:
> i.MX8QXP is an ARMv8 SoC which has a Cortex-M4 system controller
> inside, the system controller is in charge of controlling power,
> clock and scu key etc..
>
> Adds i.MX system controller key driver support, Linux kernel has
> to communicate with system controller via MU (message unit) IPC
> to get scu key's status.
>
> Signed-off-by: Anson Huang <Anson.Huang@xxxxxxx>
> ---
> Changes since V3:
> - switch the debounce and repeat interval time for delay work schdule;
> - add .remove to handle group irq and notify etc..
> ---
> drivers/input/keyboard/Kconfig | 7 ++
> drivers/input/keyboard/Makefile | 1 +
> drivers/input/keyboard/imx_sc_key.c | 190 ++++++++++++++++++++++++++++++++++++
> 3 files changed, 198 insertions(+)
> create mode 100644 drivers/input/keyboard/imx_sc_key.c
>
> diff --git a/drivers/input/keyboard/Kconfig b/drivers/input/keyboard/Kconfig
> index 8911bc2..00f8428 100644
> --- a/drivers/input/keyboard/Kconfig
> +++ b/drivers/input/keyboard/Kconfig
> @@ -469,6 +469,13 @@ config KEYBOARD_IMX
> To compile this driver as a module, choose M here: the
> module will be called imx_keypad.
>
> +config KEYBOARD_IMX_SC_KEY
> + tristate "IMX SCU Key Driver"
> + depends on IMX_SCU
> + help
> + This is the system controller key driver for NXP i.MX SoCs with
> + system controller inside.
> +
> config KEYBOARD_NEWTON
> tristate "Newton keyboard"
> select SERIO
> diff --git a/drivers/input/keyboard/Makefile b/drivers/input/keyboard/Makefile
> index 9510325..f5b1752 100644
> --- a/drivers/input/keyboard/Makefile
> +++ b/drivers/input/keyboard/Makefile
> @@ -29,6 +29,7 @@ obj-$(CONFIG_KEYBOARD_HIL) += hil_kbd.o
> obj-$(CONFIG_KEYBOARD_HIL_OLD) += hilkbd.o
> obj-$(CONFIG_KEYBOARD_IPAQ_MICRO) += ipaq-micro-keys.o
> obj-$(CONFIG_KEYBOARD_IMX) += imx_keypad.o
> +obj-$(CONFIG_KEYBOARD_IMX_SC_KEY) += imx_sc_key.o
> obj-$(CONFIG_KEYBOARD_HP6XX) += jornada680_kbd.o
> obj-$(CONFIG_KEYBOARD_HP7XX) += jornada720_kbd.o
> obj-$(CONFIG_KEYBOARD_LKKBD) += lkkbd.o
> diff --git a/drivers/input/keyboard/imx_sc_key.c b/drivers/input/keyboard/imx_sc_key.c
> new file mode 100644
> index 0000000..59c68fa
> --- /dev/null
> +++ b/drivers/input/keyboard/imx_sc_key.c
> @@ -0,0 +1,190 @@
> +// SPDX-License-Identifier: GPL-2.0
> +/*
> + * Copyright 2019 NXP.
> + */
> +
> +#include <linux/device.h>
> +#include <linux/err.h>
> +#include <linux/firmware/imx/sci.h>
> +#include <linux/init.h>
> +#include <linux/input.h>
> +#include <linux/interrupt.h>
> +#include <linux/jiffies.h>
> +#include <linux/kernel.h>
> +#include <linux/module.h>
> +#include <linux/of.h>
> +#include <linux/of_address.h>
> +#include <linux/platform_device.h>
> +
> +#define DEBOUNCE_TIME 100
> +#define REPEAT_INTERVAL 60
> +
> +#define SC_IRQ_BUTTON 1
> +#define SC_IRQ_GROUP_WAKE 3
> +#define IMX_SC_MISC_FUNC_GET_BUTTON_STATUS 18
> +
> +struct imx_key_drv_data {
> + int keycode;
> + bool keystate; /* 1: pressed, 0: release */
> + bool delay_check;
> + struct delayed_work check_work;
> + struct input_dev *input;
> + struct imx_sc_ipc *key_ipc_handle;
> + struct notifier_block key_notifier;
> +};
> +
> +struct imx_sc_msg_key {
> + struct imx_sc_rpc_msg hdr;
> + u8 state;
> +};
> +
> +static int imx_sc_key_notify(struct notifier_block *nb,
> + unsigned long event, void *group)
> +{
> + struct imx_key_drv_data *priv =
> + container_of(nb,
> + struct imx_key_drv_data,
> + key_notifier);
> +
> + if ((event & SC_IRQ_BUTTON) && (*(u8 *)group == SC_IRQ_GROUP_WAKE)
> + && !priv->delay_check) {
> + priv->delay_check = 1;
> + schedule_delayed_work(&priv->check_work,
> + msecs_to_jiffies(DEBOUNCE_TIME));
If I am reading this right, you are trying to avoid scheduling the work
again if it is already scheduled. You do not need to do that, as
schedule_delayed_work() will take care of that (if you want to make sure
the work is re-scheduled with updated expiration, you need to use
mod_delayed_work).
> + }
> +
> + return 0;
> +}
> +
> +static void imx_sc_check_for_events(struct work_struct *work)
> +{
> + struct imx_key_drv_data *priv =
> + container_of(work,
> + struct imx_key_drv_data,
> + check_work.work);
> + struct input_dev *input = priv->input;
> + struct imx_sc_msg_key msg;
> + struct imx_sc_rpc_msg *hdr = &msg.hdr;
> + bool state;
> + int ret;
> +
> + hdr->ver = IMX_SC_RPC_VERSION;
> + hdr->svc = IMX_SC_RPC_SVC_MISC;
> + hdr->func = IMX_SC_MISC_FUNC_GET_BUTTON_STATUS;
> + hdr->size = 1;
> +
> + ret = imx_scu_call_rpc(priv->key_ipc_handle, &msg, true);
> + if (ret) {
> + dev_err(&input->dev, "read imx sc key failed, ret %d\n", ret);
> + return;
> + }
> +
> + state = (bool)msg.state;
> +
> + if (!state && !priv->keystate)
> + state = true;
This needs an explanation please.
> +
> + if (state ^ priv->keystate) {
> + pm_wakeup_event(input->dev.parent, 0);
I'd expect this happening in imx_sc_key_notify() so that the device
would have a change to run this work.
> + priv->keystate = state;
> + input_event(input, EV_KEY, priv->keycode, state);
> + input_sync(input);
> + if (!state)
> + priv->delay_check = 0;
> + pm_relax(priv->input->dev.parent);
Are you sure you want to call pm_relax() unconditionally, and not when
state == false (i.e. button released)?
> + }
> +
> + if (state)
> + schedule_delayed_work(&priv->check_work,
> + msecs_to_jiffies(REPEAT_INTERVAL));
> +}
> +
> +static int imx_sc_key_probe(struct platform_device *pdev)
> +{
> + struct device_node *np = pdev->dev.of_node;
> + static struct imx_key_drv_data *priv;
> + struct input_dev *input;
> + int ret;
> +
> + priv = devm_kzalloc(&pdev->dev, sizeof(*priv), GFP_KERNEL);
> + if (!priv)
> + return -ENOMEM;
> +
> + ret = imx_scu_get_handle(&priv->key_ipc_handle);
> + if (ret)
> + return ret;
> +
> + if (of_property_read_u32(np, "linux,keycode", &priv->keycode)) {
> + dev_err(&pdev->dev, "missing KEY_POWER in DT\n");
> + return -EINVAL;
> + }
> +
> + INIT_DELAYED_WORK(&priv->check_work, imx_sc_check_for_events);
> +
> + input = devm_input_allocate_device(&pdev->dev);
> + if (!input) {
> + dev_err(&pdev->dev, "failed to allocate the input device\n");
> + return -ENOMEM;
> + }
> +
> + input->name = pdev->name;
> + input->phys = "imx-sc-key/input0";
> + input->id.bustype = BUS_HOST;
> +
> + input_set_capability(input, EV_KEY, priv->keycode);
> +
> + ret = input_register_device(input);
> + if (ret) {
Could you please rename this (and elsewhere) from 'ret' to 'error'?
> + dev_err(&pdev->dev, "failed to register input device\n");
> + return ret;
> + }
> +
> + priv->input = input;
> + platform_set_drvdata(pdev, priv);
> +
> + ret = imx_scu_irq_group_enable(SC_IRQ_GROUP_WAKE, SC_IRQ_BUTTON, true);
> + if (ret) {
> + dev_warn(&pdev->dev, "enable scu group irq failed\n");
> + return ret;
> + }
> +
> + priv->key_notifier.notifier_call = imx_sc_key_notify;
> + ret = imx_scu_irq_register_notifier(&priv->key_notifier);
> + if (ret) {
> + imx_scu_irq_group_enable(SC_IRQ_GROUP_WAKE, SC_IRQ_BUTTON, false);
> + dev_warn(&pdev->dev, "register scu notifier failed\n");
return error;
> + }
> +
> + return ret;
return 0;
> +}
> +
> +static int imx_sc_key_remove(struct platform_device *pdev)
> +{
> + struct imx_key_drv_data *priv = platform_get_drvdata(pdev);
> +
> + imx_scu_irq_group_enable(SC_IRQ_GROUP_WAKE, SC_IRQ_BUTTON, false);
> + imx_scu_irq_unregister_notifier(&priv->key_notifier);
> + cancel_delayed_work_sync(&priv->check_work);
> +
> + return 0;
> +}
> +
> +static const struct of_device_id imx_sc_key_ids[] = {
> + { .compatible = "fsl,imx-sc-key" },
> + { /* sentinel */ }
> +};
> +MODULE_DEVICE_TABLE(of, imx_sc_key_ids);
> +
> +static struct platform_driver imx_sc_key_driver = {
> + .driver = {
> + .name = "imx-sc-key",
> + .of_match_table = imx_sc_key_ids,
> + },
> + .probe = imx_sc_key_probe,
> + .remove = imx_sc_key_remove,
> +};
> +module_platform_driver(imx_sc_key_driver);
> +
> +MODULE_AUTHOR("Anson Huang <Anson.Huang@xxxxxxx>");
> +MODULE_DESCRIPTION("i.MX System Controller Key Driver");
> +MODULE_LICENSE("GPL v2");
> --
> 2.7.4
>
Thanks.
--
Dmitry
