Input: add powerkey driver for HISI 65xx SoC

This driver provides a input driver for the power button on the
HiSi 65xx SoC for boards like HiKey.

This driver was originally by Zhiliang Xue <xuezhiliang@huawei.com>
then basically rewritten by Jorge, but preserving the original
module author credits.

Signed-off-by: Jorge Ramirez-Ortiz <jorge.ramirez-ortiz@linaro.org>
[jstultz: Reworked commit message, folded in other fixes/cleanups
from Jorge, implemented some larger cleanups suggested by DmitryT]
Signed-off-by: John Stultz <john.stultz@linaro.org>
Signed-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>

3 files changed, 152 insertions, 0 deletions

diff --git a/drivers/input/misc/Kconfig b/drivers/input/misc/Kconfig
index 27d6da0e354a..efb0ca871327 100644
--- a/drivers/input/misc/Kconfig
+++ b/drivers/input/misc/Kconfig
@@ -810,4 +810,13 @@ config INPUT_DRV2667_HAPTICS
           To compile this driver as a module, choose M here: the
           module will be called drv2667-haptics.
 
+config INPUT_HISI_POWERKEY
+        tristate "Hisilicon PMIC ONKEY support"
+        depends on ARCH_HISI || COMPILE_TEST
+        help
+          Say Y to enable support for PMIC ONKEY.
+
+          To compile this driver as a module, choose M here: the
+          module will be called hisi_powerkey.
+
 endif
diff --git a/drivers/input/misc/Makefile b/drivers/input/misc/Makefile
index 5373f493f370..6a1e5e20fc1c 100644
--- a/drivers/input/misc/Makefile
+++ b/drivers/input/misc/Makefile
@@ -35,6 +35,7 @@ obj-$(CONFIG_INPUT_DRV2667_HAPTICS)	+= drv2667.o
 obj-$(CONFIG_INPUT_GP2A)                += gp2ap002a00f.o
 obj-$(CONFIG_INPUT_GPIO_BEEPER)         += gpio-beeper.o
 obj-$(CONFIG_INPUT_GPIO_TILT_POLLED)    += gpio_tilt_polled.o
+obj-$(CONFIG_INPUT_HISI_POWERKEY)       += hisi_powerkey.o
 obj-$(CONFIG_HP_SDC_RTC)                += hp_sdc_rtc.o
 obj-$(CONFIG_INPUT_IMS_PCU)             += ims-pcu.o
 obj-$(CONFIG_INPUT_IXP4XX_BEEPER)       += ixp4xx-beeper.o
diff --git a/drivers/input/misc/hisi_powerkey.c b/drivers/input/misc/hisi_powerkey.c
new file mode 100644
index 000000000000..675539c529ce
--- /dev/null
+++ b/drivers/input/misc/hisi_powerkey.c
@@ -0,0 +1,142 @@
+/*
+ * Hisilicon PMIC powerkey driver
+ *
+ * Copyright (C) 2013 Hisilicon Ltd.
+ * Copyright (C) 2015, 2016 Linaro Ltd.
+ *
+ * This file is subject to the terms and conditions of the GNU General
+ * Public License. See the file "COPYING" in the main directory of this
+ * archive for more details.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ */
+
+#include <linux/platform_device.h>
+#include <linux/interrupt.h>
+#include <linux/reboot.h>
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/of_irq.h>
+#include <linux/input.h>
+#include <linux/slab.h>
+
+/* the held interrupt will trigger after 4 seconds */
+#define MAX_HELD_TIME   (4 * MSEC_PER_SEC)
+
+static irqreturn_t hi65xx_power_press_isr(int irq, void *q)
+{
+        struct input_dev *input = q;
+
+        pm_wakeup_event(input->dev.parent, MAX_HELD_TIME);
+        input_report_key(input, KEY_POWER, 1);
+        input_sync(input);
+
+        return IRQ_HANDLED;
+}
+
+static irqreturn_t hi65xx_power_release_isr(int irq, void *q)
+{
+        struct input_dev *input = q;
+
+        pm_wakeup_event(input->dev.parent, MAX_HELD_TIME);
+        input_report_key(input, KEY_POWER, 0);
+        input_sync(input);
+
+        return IRQ_HANDLED;
+}
+
+static irqreturn_t hi65xx_restart_toggle_isr(int irq, void *q)
+{
+        struct input_dev *input = q;
+        int value = test_bit(KEY_RESTART, input->key);
+
+        pm_wakeup_event(input->dev.parent, MAX_HELD_TIME);
+        input_report_key(input, KEY_RESTART, !value);
+        input_sync(input);
+
+        return IRQ_HANDLED;
+}
+
+static const struct {
+        const char *name;
+        irqreturn_t (*handler)(int irq, void *q);
+} hi65xx_irq_info[] = {
+        { "down", hi65xx_power_press_isr },
+        { "up", hi65xx_power_release_isr },
+        { "hold 4s", hi65xx_restart_toggle_isr },
+};
+
+static int hi65xx_powerkey_probe(struct platform_device *pdev)
+{
+        struct device *dev = &pdev->dev;
+        struct input_dev *input;
+        int irq, i, error;
+
+        input = devm_input_allocate_device(&pdev->dev);
+        if (!input) {
+                dev_err(&pdev->dev, "failed to allocate input device\n");
+                return -ENOMEM;
+        }
+
+        input->phys = "hisi_on/input0";
+        input->name = "HISI 65xx PowerOn Key";
+
+        input_set_capability(input, EV_KEY, KEY_POWER);
+        input_set_capability(input, EV_KEY, KEY_RESTART);
+
+        for (i = 0; i < ARRAY_SIZE(hi65xx_irq_info); i++) {
+
+                irq = platform_get_irq_byname(pdev, hi65xx_irq_info[i].name);
+                if (irq < 0) {
+                        error = irq;
+                        dev_err(dev, "couldn't get irq %s: %d\n",
+                                hi65xx_irq_info[i].name, error);
+                        return error;
+                }
+
+                error = devm_request_any_context_irq(dev, irq,
+                                                     hi65xx_irq_info[i].handler,
+                                                     IRQF_ONESHOT,
+                                                     hi65xx_irq_info[i].name,
+                                                     input);
+                if (error < 0) {
+                        dev_err(dev, "couldn't request irq %s: %d\n",
+                                hi65xx_irq_info[i].name, error);
+                        return error;
+                }
+        }
+
+        error = input_register_device(input);
+        if (error) {
+                dev_err(&pdev->dev, "failed to register input device: %d\n",
+                        error);
+                return error;
+        }
+
+        device_init_wakeup(&pdev->dev, 1);
+
+        return 0;
+}
+
+static int hi65xx_powerkey_remove(struct platform_device *pdev)
+{
+        device_init_wakeup(&pdev->dev, 0);
+
+        return 0;
+}
+
+static struct platform_driver hi65xx_powerkey_driver = {
+        .driver = {
+                .name = "hi65xx-powerkey",
+        },
+        .probe = hi65xx_powerkey_probe,
+        .remove  = hi65xx_powerkey_remove,
+};
+module_platform_driver(hi65xx_powerkey_driver);
+
+MODULE_AUTHOR("Zhiliang Xue <xuezhiliang@huawei.com");
+MODULE_DESCRIPTION("Hisi PMIC Power key driver");
+MODULE_LICENSE("GPL v2");