[PATCH v21 2/3] Input: mt6779-keypad - Add MediaTek keypad driver

Mattijs Korpershoek
2022-03-03T15:43:44Z

From: "fengping.yu" <fengping.yu@mediatek.com>

This patch adds matrix keypad support for Mediatek SoCs.

Signed-off-by: fengping.yu <fengping.yu@mediatek.com>
Reviewed-by: Marco Felsch <m.felsch@pengutronix.de>
Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Reviewed-by: Mattijs Korpershoek <mkorpershoek@baylibre.com>
Signed-off-by: Mattijs Korpershoek <mkorpershoek@baylibre.com>
---
drivers/input/keyboard/Kconfig | 12 ++
drivers/input/keyboard/Makefile | 1 +
drivers/input/keyboard/mt6779-keypad.c | 215 +++++++++++++++++++++++++
3 files changed, 228 insertions(+)
create mode 100644 drivers/input/keyboard/mt6779-keypad.c

diff --git a/drivers/input/keyboard/Kconfig b/drivers/input/keyboard/Kconfig
index 0c607da9ee10..03a9530f620e 100644
--- a/drivers/input/keyboard/Kconfig
+++ b/drivers/input/keyboard/Kconfig
@@ -779,6 +779,18 @@ config KEYBOARD_BCM
To compile this driver as a module, choose M here: the
module will be called bcm-keypad.

+config KEYBOARD_MT6779
+ tristate "MediaTek Keypad Support"
+ depends on ARCH_MEDIATEK || COMPILE_TEST
+ select REGMAP_MMIO
+ select INPUT_MATRIXKMAP
+ help
+ Say Y here if you want to use the keypad on MediaTek SoCs.
+ If unsure, say N.
+
+ To compile this driver as a module, choose M here: the
+ module will be called mt6779-keypad.
+
config KEYBOARD_MTK_PMIC
tristate "MediaTek PMIC keys support"
depends on MFD_MT6397
diff --git a/drivers/input/keyboard/Makefile b/drivers/input/keyboard/Makefile
index e3c8648f834e..721936e90290 100644
--- a/drivers/input/keyboard/Makefile
+++ b/drivers/input/keyboard/Makefile
@@ -44,6 +44,7 @@ obj-$(CONFIG_KEYBOARD_MATRIX) += matrix_keypad.o
obj-$(CONFIG_KEYBOARD_MAX7359) += max7359_keypad.o
obj-$(CONFIG_KEYBOARD_MCS) += mcs_touchkey.o
obj-$(CONFIG_KEYBOARD_MPR121) += mpr121_touchkey.o
+obj-$(CONFIG_KEYBOARD_MT6779) += mt6779-keypad.o
obj-$(CONFIG_KEYBOARD_MTK_PMIC) += mtk-pmic-keys.o
obj-$(CONFIG_KEYBOARD_NEWTON) += newtonkbd.o
obj-$(CONFIG_KEYBOARD_NOMADIK) += nomadik-ske-keypad.o
diff --git a/drivers/input/keyboard/mt6779-keypad.c b/drivers/input/keyboard/mt6779-keypad.c
new file mode 100644
index 000000000000..b207acdd1e2a
--- /dev/null
+++ b/drivers/input/keyboard/mt6779-keypad.c
@@ -0,0 +1,215 @@
+// 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/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_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;
+ void __iomem *base;
+ u32 n_rows;
+ u32 n_cols;
+ 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;
+ unsigned short *keycode = keypad->input_dev->keycode;
+ DECLARE_BITMAP(new_state, MTK_KPD_NUM_BITS);
+ DECLARE_BITMAP(change, MTK_KPD_NUM_BITS);
+ int bit_nr;
+ int pressed;
+ unsigned short code;
+ int row, col;
+ int row_shift = get_count_order(keypad->n_cols);
+
+ 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) {
+ /* For 32bits register, only bits [15:0] use to indicate key status */
+ if (bit_nr % 32 >= 16)
+ continue;
+
+ /* 1: not pressed, 0: pressed */
+ pressed = !test_bit(bit_nr, new_state);
+ dev_dbg(&keypad->input_dev->dev, "%s",
+ pressed ? "pressed" : "released");
+
+ row = bit_nr / 32;
+ col = bit_nr % 32;
+
+ code = keycode[MATRIX_SCAN_CODE(row, col, row_shift)];
+
+ input_report_key(keypad->input_dev, code, pressed);
+ input_sync(keypad->input_dev);
+
+ dev_dbg(&keypad->input_dev->dev,
+ "report Linux keycode = %d\n", code);
+ }
+
+ 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 int mt6779_keypad_pdrv_probe(struct platform_device *pdev)
+{
+ struct mt6779_keypad *keypad;
+ unsigned int irq;
+ u32 debounce;
+ bool wakeup;
+ int error;
+
+ keypad = devm_kzalloc(&pdev->dev, sizeof(*keypad), GFP_KERNEL);
+ if (!keypad)
+ return -ENOMEM;
+
+ keypad->base = devm_platform_ioremap_resource(pdev, 0);
+ if (IS_ERR(keypad->base))
+ return PTR_ERR(keypad->base);
+
+ keypad->regmap = devm_regmap_init_mmio(&pdev->dev,
+ keypad->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;
+ }
+
+ 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;
+ }
+
+ regmap_write(keypad->regmap, MTK_KPD_DEBOUNCE,
+ (debounce * (1 << 5)) & MTK_KPD_DEBOUNCE_MASK);
+
+ 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 fail\n");
+
+ 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");
--
2.32.0