1 files changed, 275 insertions, 0 deletions
diff --git a/drivers/input/keyboard/mt6779-keypad.c b/drivers/input/keyboard/mt6779-keypad.c
new file mode 100644
index 000000000000..19f69d167fbd
--- /dev/null
+++ b/drivers/input/keyboard/mt6779-keypad.c
@@ -0,0 +1,275 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Copyright (C) 2022 MediaTek Inc.
+ * Author Fengping Yu <fengping.yu@mediatek.com>
+ */
+#include <linux/bitops.h>
+#include <linux/clk.h>
+#include <linux/input.h>
+#include <linux/input/matrix_keypad.h>
+#include <linux/interrupt.h>
+#include <linux/module.h>
+#include <linux/property.h>
+#include <linux/platform_device.h>
+#include <linux/regmap.h>
+
+#define MTK_KPD_NAME		"mt6779-keypad"
+#define MTK_KPD_MEM		0x0004
+#define MTK_KPD_DEBOUNCE	0x0018
+#define MTK_KPD_DEBOUNCE_MASK	GENMASK(13, 0)
+#define MTK_KPD_DEBOUNCE_MAX_MS	256
+#define MTK_KPD_SEL		0x0020
+#define MTK_KPD_SEL_DOUBLE_KP_MODE	BIT(0)
+#define MTK_KPD_SEL_COL	GENMASK(15, 10)
+#define MTK_KPD_SEL_ROW	GENMASK(9, 4)
+#define MTK_KPD_SEL_COLMASK(c)	GENMASK((c) + 9, 10)
+#define MTK_KPD_SEL_ROWMASK(r)	GENMASK((r) + 3, 4)
+#define MTK_KPD_NUM_MEMS	5
+#define MTK_KPD_NUM_BITS	136	/* 4*32+8 MEM5 only use 8 BITS */
+
+struct mt6779_keypad {
+	struct regmap *regmap;
+	struct input_dev *input_dev;
+	struct clk *clk;
+	u32 n_rows;
+	u32 n_cols;
+	void (*calc_row_col)(unsigned int key,
+			     unsigned int *row, unsigned int *col);
+	DECLARE_BITMAP(keymap_state, MTK_KPD_NUM_BITS);
+};
+
+static const struct regmap_config mt6779_keypad_regmap_cfg = {
+	.reg_bits = 32,
+	.val_bits = 32,
+	.reg_stride = sizeof(u32),
+	.max_register = 36,
+};
+
+static irqreturn_t mt6779_keypad_irq_handler(int irq, void *dev_id)
+{
+	struct mt6779_keypad *keypad = dev_id;
+	const unsigned short *keycode = keypad->input_dev->keycode;
+	DECLARE_BITMAP(new_state, MTK_KPD_NUM_BITS);
+	DECLARE_BITMAP(change, MTK_KPD_NUM_BITS);
+	unsigned int bit_nr, key;
+	unsigned int row, col;
+	unsigned int scancode;
+	unsigned int row_shift = get_count_order(keypad->n_cols);
+	bool pressed;
+
+	regmap_bulk_read(keypad->regmap, MTK_KPD_MEM,
+			 new_state, MTK_KPD_NUM_MEMS);
+
+	bitmap_xor(change, new_state, keypad->keymap_state, MTK_KPD_NUM_BITS);
+
+	for_each_set_bit(bit_nr, change, MTK_KPD_NUM_BITS) {
+		/*
+		 * Registers are 32bits, but only bits [15:0] are used to
+		 * indicate key status.
+		 */
+		if (bit_nr % 32 >= 16)
+			continue;
+
+		key = bit_nr / 32 * 16 + bit_nr % 32;
+		keypad->calc_row_col(key, &row, &col);
+
+		scancode = MATRIX_SCAN_CODE(row, col, row_shift);
+		/* 1: not pressed, 0: pressed */
+		pressed = !test_bit(bit_nr, new_state);
+		dev_dbg(&keypad->input_dev->dev, "%s",
+			pressed ? "pressed" : "released");
+
+		input_event(keypad->input_dev, EV_MSC, MSC_SCAN, scancode);
+		input_report_key(keypad->input_dev, keycode[scancode], pressed);
+		input_sync(keypad->input_dev);
+
+		dev_dbg(&keypad->input_dev->dev,
+			"report Linux keycode = %d\n", keycode[scancode]);
+	}
+
+	bitmap_copy(keypad->keymap_state, new_state, MTK_KPD_NUM_BITS);
+
+	return IRQ_HANDLED;
+}
+
+static void mt6779_keypad_clk_disable(void *data)
+{
+	clk_disable_unprepare(data);
+}
+
+static void mt6779_keypad_calc_row_col_single(unsigned int key,
+					      unsigned int *row,
+					      unsigned int *col)
+{
+	*row = key / 9;
+	*col = key % 9;
+}
+
+static void mt6779_keypad_calc_row_col_double(unsigned int key,
+					      unsigned int *row,
+					      unsigned int *col)
+{
+	*row = key / 13;
+	*col = (key % 13) / 2;
+}
+
+static int mt6779_keypad_pdrv_probe(struct platform_device *pdev)
+{
+	struct mt6779_keypad *keypad;
+	void __iomem *base;
+	int irq;
+	u32 debounce;
+	u32 keys_per_group;
+	bool wakeup;
+	int error;
+
+	keypad = devm_kzalloc(&pdev->dev, sizeof(*keypad), GFP_KERNEL);
+	if (!keypad)
+		return -ENOMEM;
+
+	base = devm_platform_ioremap_resource(pdev, 0);
+	if (IS_ERR(base))
+		return PTR_ERR(base);
+
+	keypad->regmap = devm_regmap_init_mmio(&pdev->dev, base,
+					       &mt6779_keypad_regmap_cfg);
+	if (IS_ERR(keypad->regmap)) {
+		dev_err(&pdev->dev,
+			"regmap init failed:%pe\n", keypad->regmap);
+		return PTR_ERR(keypad->regmap);
+	}
+
+	bitmap_fill(keypad->keymap_state, MTK_KPD_NUM_BITS);
+
+	keypad->input_dev = devm_input_allocate_device(&pdev->dev);
+	if (!keypad->input_dev) {
+		dev_err(&pdev->dev, "Failed to allocate input dev\n");
+		return -ENOMEM;
+	}
+
+	keypad->input_dev->name = MTK_KPD_NAME;
+	keypad->input_dev->id.bustype = BUS_HOST;
+
+	error = matrix_keypad_parse_properties(&pdev->dev, &keypad->n_rows,
+					       &keypad->n_cols);
+	if (error) {
+		dev_err(&pdev->dev, "Failed to parse keypad params\n");
+		return error;
+	}
+
+	if (device_property_read_u32(&pdev->dev, "debounce-delay-ms",
+				     &debounce))
+		debounce = 16;
+
+	if (debounce > MTK_KPD_DEBOUNCE_MAX_MS) {
+		dev_err(&pdev->dev,
+			"Debounce time exceeds the maximum allowed time %dms\n",
+			MTK_KPD_DEBOUNCE_MAX_MS);
+		return -EINVAL;
+	}
+
+	if (device_property_read_u32(&pdev->dev, "mediatek,keys-per-group",
+				     &keys_per_group))
+		keys_per_group = 1;
+
+	switch (keys_per_group) {
+	case 1:
+		keypad->calc_row_col = mt6779_keypad_calc_row_col_single;
+		break;
+	case 2:
+		keypad->calc_row_col = mt6779_keypad_calc_row_col_double;
+		break;
+	default:
+		dev_err(&pdev->dev,
+			"Invalid keys-per-group: %d\n", keys_per_group);
+		return -EINVAL;
+	}
+
+	wakeup = device_property_read_bool(&pdev->dev, "wakeup-source");
+
+	dev_dbg(&pdev->dev, "n_row=%d n_col=%d debounce=%d\n",
+		keypad->n_rows, keypad->n_cols, debounce);
+
+	error = matrix_keypad_build_keymap(NULL, NULL,
+					   keypad->n_rows, keypad->n_cols,
+					   NULL, keypad->input_dev);
+	if (error) {
+		dev_err(&pdev->dev, "Failed to build keymap\n");
+		return error;
+	}
+
+	input_set_capability(keypad->input_dev, EV_MSC, MSC_SCAN);
+
+	regmap_write(keypad->regmap, MTK_KPD_DEBOUNCE,
+		     (debounce * (1 << 5)) & MTK_KPD_DEBOUNCE_MASK);
+
+	if (keys_per_group == 2)
+		regmap_update_bits(keypad->regmap, MTK_KPD_SEL,
+				   MTK_KPD_SEL_DOUBLE_KP_MODE,
+				   MTK_KPD_SEL_DOUBLE_KP_MODE);
+
+	regmap_update_bits(keypad->regmap, MTK_KPD_SEL, MTK_KPD_SEL_ROW,
+			   MTK_KPD_SEL_ROWMASK(keypad->n_rows));
+	regmap_update_bits(keypad->regmap, MTK_KPD_SEL, MTK_KPD_SEL_COL,
+			   MTK_KPD_SEL_COLMASK(keypad->n_cols));
+
+	keypad->clk = devm_clk_get(&pdev->dev, "kpd");
+	if (IS_ERR(keypad->clk))
+		return PTR_ERR(keypad->clk);
+
+	error = clk_prepare_enable(keypad->clk);
+	if (error) {
+		dev_err(&pdev->dev, "cannot prepare/enable keypad clock\n");
+		return error;
+	}
+
+	error = devm_add_action_or_reset(&pdev->dev, mt6779_keypad_clk_disable,
+					 keypad->clk);
+	if (error)
+		return error;
+
+	irq = platform_get_irq(pdev, 0);
+	if (irq < 0)
+		return irq;
+
+	error = devm_request_threaded_irq(&pdev->dev, irq,
+					  NULL, mt6779_keypad_irq_handler,
+					  IRQF_ONESHOT, MTK_KPD_NAME, keypad);
+	if (error) {
+		dev_err(&pdev->dev, "Failed to request IRQ#%d: %d\n",
+			irq, error);
+		return error;
+	}
+
+	error = input_register_device(keypad->input_dev);
+	if (error) {
+		dev_err(&pdev->dev, "Failed to register device\n");
+		return error;
+	}
+
+	error = device_init_wakeup(&pdev->dev, wakeup);
+	if (error)
+		dev_warn(&pdev->dev, "device_init_wakeup() failed: %d\n",
+			 error);
+
+	return 0;
+}
+
+static const struct of_device_id mt6779_keypad_of_match[] = {
+	{ .compatible = "mediatek,mt6779-keypad" },
+	{ .compatible = "mediatek,mt6873-keypad" },
+	{ /* sentinel */ }
+};
+
+static struct platform_driver mt6779_keypad_pdrv = {
+	.probe = mt6779_keypad_pdrv_probe,
+	.driver = {
+		   .name = MTK_KPD_NAME,
+		   .of_match_table = mt6779_keypad_of_match,
+	},
+};
+module_platform_driver(mt6779_keypad_pdrv);
+
+MODULE_AUTHOR("Mediatek Corporation");
+MODULE_DESCRIPTION("MTK Keypad (KPD) Driver");
+MODULE_LICENSE("GPL");