[PATCH 3/4] input: Add MediaTek PMIC keys support

[Chen Zhong <chen.zhong@mediatek.com>]

This patch add support to handle MediaTek PMIC MT6397/MT6323 key
interrupts including pwrkey and homekey, also add setting for
long press key shutdown behavior.

Signed-off-by: Chen Zhong <chen.zhong@mediatek.com>
---
 drivers/input/keyboard/mtk-pmic-keys.c |  320 ++++++++++++++++++++++++++++++++
 1 file changed, 320 insertions(+)
 create mode 100644 drivers/input/keyboard/mtk-pmic-keys.c

diff --git a/drivers/input/keyboard/mtk-pmic-keys.c b/drivers/input/keyboard/mtk-pmic-keys.c
new file mode 100644
index 0000000..0ea7d17
--- /dev/null
+++ b/drivers/input/keyboard/mtk-pmic-keys.c
@@ -0,0 +1,320 @@
+/*
+ * Copyright (C) 2017 MediaTek, Inc.
+ *
+ * Author: Chen Zhong <chen.zhong@mediatek.com>
+ *
+ * This software is licensed under the terms of the GNU General Public
+ * License version 2, as published by the Free Software Foundation, and
+ * may be copied, distributed, and modified under those terms.
+ *
+ * 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/ioctl.h>
+#include <linux/module.h>
+#include <linux/kernel.h>
+#include <linux/input.h>
+#include <linux/interrupt.h>
+#include <linux/platform_device.h>
+#include <linux/kernel.h>
+#include <linux/of.h>
+#include <linux/of_device.h>
+#include <linux/regmap.h>
+#include <linux/mfd/mt6323/registers.h>
+#include <linux/mfd/mt6397/registers.h>
+#include <linux/mfd/mt6397/core.h>
+#include <linux/slab.h>
+#include <linux/irqdomain.h>
+
+#define PWRKEY_RST_EN_MASK  0x1
+#define PWRKEY_RST_EN_SHIFT  6
+#define HOMEKEY_RST_EN_MASK  0x1
+#define HOMEKEY_RST_EN_SHIFT  5
+#define RST_DU_MASK  0x3
+#define RST_DU_SHIFT  8
+
+struct pmic_keys_regs {
+	u32 deb_reg;
+	u32 deb_mask;
+	u32 intsel_reg;
+	u32 intsel_mask;
+};
+
+#define PMIC_KEYS_REGS(_deb_reg, _deb_mask, _intsel_reg, _intsel_mask)	\
+{									\
+	.deb_reg		= _deb_reg,				\
+	.deb_mask		= _deb_mask,				\
+	.intsel_reg		= _intsel_reg,				\
+	.intsel_mask		= _intsel_mask,				\
+}
+
+struct pmic_regs {
+	const struct pmic_keys_regs pwrkey_regs;
+	const struct pmic_keys_regs homekey_regs;
+	u32 pmic_rst_reg;
+};
+
+static const struct pmic_regs mt6397_regs = {
+	.pwrkey_regs = PMIC_KEYS_REGS(MT6397_CHRSTATUS,
+		0x8, MT6397_INT_RSV, 0x10),
+	.homekey_regs = PMIC_KEYS_REGS(MT6397_OCSTATUS2,
+		0x10, MT6397_INT_RSV, 0x8),
+	.pmic_rst_reg = MT6397_TOP_RST_MISC,
+};
+
+static const struct pmic_regs mt6323_regs = {
+	.pwrkey_regs = PMIC_KEYS_REGS(MT6323_CHRSTATUS,
+		0x2, MT6323_INT_MISC_CON, 0x10),
+	.homekey_regs = PMIC_KEYS_REGS(MT6323_CHRSTATUS,
+		0x4, MT6323_INT_MISC_CON, 0x8),
+	.pmic_rst_reg = MT6323_TOP_RST_MISC,
+};
+
+struct pmic_keys_info {
+	struct mtk_pmic_keys *keys;
+	const struct pmic_keys_regs *regs;
+	int keycode;
+	int irq;
+	u32 hw_irq;
+};
+
+struct mtk_pmic_keys {
+	struct input_dev *input_dev;
+	struct device *dev;
+	struct regmap *regmap;
+	struct irq_domain *irq_domain;
+	struct pmic_keys_info pwrkey, homekey;
+};
+
+enum long_press_mode {
+	LP_DISABLE,
+	LP_ONEKEY,
+	LP_TWOKEY,
+};
+
+static void long_press_reset_setup(struct mtk_pmic_keys *keys, u32 pmic_rst_reg)
+{
+	int ret;
+	u32 long_press_mode, long_press_duration;
+
+	ret = of_property_read_u32(keys->dev->of_node,
+		"mediatek,long-press-duration", &long_press_duration);
+	if (ret)
+		long_press_duration = 0;
+
+	regmap_update_bits(keys->regmap, pmic_rst_reg,
+		RST_DU_MASK << RST_DU_SHIFT,
+		long_press_duration << RST_DU_SHIFT);
+	regmap_update_bits(keys->regmap, pmic_rst_reg,
+		PWRKEY_RST_EN_MASK << PWRKEY_RST_EN_SHIFT,
+		PWRKEY_RST_EN_MASK << PWRKEY_RST_EN_SHIFT);
+
+	ret = of_property_read_u32(keys->dev->of_node,
+		"mediatek,long-press-mode", &long_press_mode);
+
+	if (!ret && long_press_mode == LP_ONEKEY) {
+		regmap_update_bits(keys->regmap, pmic_rst_reg,
+			HOMEKEY_RST_EN_MASK << HOMEKEY_RST_EN_SHIFT, 0);
+	} else if (!ret && long_press_mode == LP_TWOKEY) {
+		regmap_update_bits(keys->regmap, pmic_rst_reg,
+			HOMEKEY_RST_EN_MASK << HOMEKEY_RST_EN_SHIFT,
+			HOMEKEY_RST_EN_MASK << HOMEKEY_RST_EN_SHIFT);
+	} else {
+		regmap_update_bits(keys->regmap, pmic_rst_reg,
+			PWRKEY_RST_EN_MASK << PWRKEY_RST_EN_SHIFT, 0);
+		regmap_update_bits(keys->regmap, pmic_rst_reg,
+			HOMEKEY_RST_EN_MASK << HOMEKEY_RST_EN_SHIFT, 0);
+	}
+}
+
+static irqreturn_t mtk_pmic_keys_irq_handler_thread(int irq, void *data)
+{
+	struct pmic_keys_info *info = data;
+	u32 key_deb, pressed;
+
+	regmap_read(info->keys->regmap, info->regs->deb_reg, &key_deb);
+
+	key_deb &= info->regs->deb_mask;
+
+	pressed = !key_deb;
+
+	input_report_key(info->keys->input_dev, info->keycode, pressed);
+	input_sync(info->keys->input_dev);
+
+	dev_info(info->keys->dev, "[PMICKEYS] (%s) key =%d using PMIC\n",
+		pressed ? "pressed" : "released", info->keycode);
+
+	return IRQ_HANDLED;
+}
+
+static int mtk_pmic_key_setup(struct mtk_pmic_keys *keys,
+		const char *propname, struct pmic_keys_info *info, bool wakeup)
+{
+	int ret;
+
+	ret = of_property_read_u32(keys->dev->of_node,
+		propname, &info->keycode);
+	if (ret)
+		return 0;
+
+	if (!info->keycode)
+		return 0;
+
+	info->keys = keys;
+
+	ret = regmap_update_bits(keys->regmap, info->regs->intsel_reg,
+			info->regs->intsel_mask, info->regs->intsel_mask);
+	if (ret < 0)
+		return ret;
+
+	info->irq = irq_create_mapping(keys->irq_domain, info->hw_irq);
+	if (info->irq <= 0)
+		return -EINVAL;
+
+	ret = devm_request_threaded_irq(keys->dev, info->irq, NULL,
+				   mtk_pmic_keys_irq_handler_thread,
+				   IRQF_ONESHOT | IRQF_TRIGGER_HIGH,
+				   "mtk-pmic-keys", info);
+	if (ret) {
+		dev_err(keys->dev, "Failed to request IRQ: %d: %d\n",
+			info->irq, ret);
+		return ret;
+	}
+
+	if (wakeup)
+		irq_set_irq_wake(info->irq, 1);
+
+	__set_bit(info->keycode, keys->input_dev->keybit);
+
+	return 0;
+}
+
+static void mtk_pmic_keys_dispose_irq(struct mtk_pmic_keys *keys)
+{
+	if (keys->pwrkey.irq)
+		irq_dispose_mapping(keys->pwrkey.irq);
+
+	if (keys->homekey.irq)
+		irq_dispose_mapping(keys->homekey.irq);
+}
+
+static const struct of_device_id of_pmic_keys_match_tbl[] = {
+	{
+		.compatible = "mediatek,mt6397-keys",
+		.data = &mt6397_regs,
+	}, {
+		.compatible = "mediatek,mt6323-keys",
+		.data = &mt6323_regs,
+	}, {
+		/* sentinel */
+	}
+};
+MODULE_DEVICE_TABLE(of, of_pmic_keys_match_tbl);
+
+static int mtk_pmic_keys_probe(struct platform_device *pdev)
+{
+	int ret;
+	struct resource *res;
+	struct mt6397_chip *pmic_chip = dev_get_drvdata(pdev->dev.parent);
+	struct mtk_pmic_keys *keys;
+	const struct pmic_regs *pmic_regs;
+	struct input_dev *input_dev;
+	const struct of_device_id *of_id =
+		of_match_device(of_pmic_keys_match_tbl, &pdev->dev);
+
+	keys = devm_kzalloc(&pdev->dev,
+		sizeof(struct mtk_pmic_keys), GFP_KERNEL);
+	if (!keys)
+		return -ENOMEM;
+
+	keys->dev = &pdev->dev;
+	keys->regmap = pmic_chip->regmap;
+	keys->irq_domain = pmic_chip->irq_domain;
+
+	pmic_regs = of_id->data;
+	keys->pwrkey.regs = &pmic_regs->pwrkey_regs;
+	keys->homekey.regs = &pmic_regs->homekey_regs;
+	res = platform_get_resource(pdev, IORESOURCE_IRQ, 0);
+	if (!res) {
+		dev_err(&pdev->dev, "no IRQ resource\n");
+		return -ENODEV;
+	}
+
+	keys->pwrkey.hw_irq = res->start;
+	keys->homekey.hw_irq = res->end;
+
+	keys->input_dev = input_dev = devm_input_allocate_device(keys->dev);
+	if (!input_dev) {
+		dev_err(&pdev->dev, "[PMICKEYS] input allocate device fail.\n");
+		return -ENOMEM;
+	}
+
+	input_dev->name = "mtk-pmic-keys";
+	input_dev->id.bustype = BUS_HOST;
+	input_dev->id.vendor = 0x0001;
+	input_dev->id.product = 0x0001;
+	input_dev->id.version = 0x0001;
+	input_dev->dev.parent = &pdev->dev;
+
+	__set_bit(EV_KEY, input_dev->evbit);
+
+	ret = mtk_pmic_key_setup(keys, "mediatek,pwrkey-code",
+		&keys->pwrkey, true);
+	if (ret)
+		goto out_dispose_irq;
+
+	ret = mtk_pmic_key_setup(keys, "mediatek,homekey-code",
+		&keys->homekey, false);
+	if (ret)
+		goto out_dispose_irq;
+
+	ret = input_register_device(input_dev);
+	if (ret) {
+		dev_err(&pdev->dev,
+			"[PMICKEYS] register input device failed (%d)\n", ret);
+		input_free_device(input_dev);
+		return ret;
+	}
+
+	input_set_drvdata(input_dev, keys);
+
+	long_press_reset_setup(keys, pmic_regs->pmic_rst_reg);
+
+	return 0;
+
+out_dispose_irq:
+	mtk_pmic_keys_dispose_irq(keys);
+	return ret;
+}
+
+static int mtk_pmic_keys_remove(struct platform_device *pdev)
+{
+	struct mtk_pmic_keys *keys = platform_get_drvdata(pdev);
+
+	mtk_pmic_keys_dispose_irq(keys);
+
+	input_unregister_device(keys->input_dev);
+
+	return 0;
+}
+
+static struct platform_driver pmic_keys_pdrv = {
+	.probe = mtk_pmic_keys_probe,
+	.remove = mtk_pmic_keys_remove,
+	.driver = {
+		   .name = "mtk-pmic-keys",
+		   .owner = THIS_MODULE,
+		   .of_match_table = of_pmic_keys_match_tbl,
+	},
+};
+
+module_platform_driver(pmic_keys_pdrv);
+
+MODULE_LICENSE("GPL v2");
+MODULE_AUTHOR("Chen Zhong <chen.zhong@mediatek.com>");
+MODULE_DESCRIPTION("MTK pmic-keys driver v0.1");
+MODULE_ALIAS("keypad:pmic");
-- 
1.7.9.5