[PATCH v10 2/3] drivers: input: keyboard: Add mtk keypad driver

Fengping Yu
2020-05-28T05:34:55Z

This adds matrix keypad support for Mediatek SoCs.

Signed-off-by: fengping.yu <fengping.yu@mediatek.com>
---
drivers/input/keyboard/Kconfig | 11 ++
drivers/input/keyboard/Makefile | 1 +
drivers/input/keyboard/mtk-kpd.c | 201 +++++++++++++++++++++++++++++++
3 files changed, 213 insertions(+)
create mode 100644 drivers/input/keyboard/mtk-kpd.c

diff --git a/drivers/input/keyboard/Kconfig b/drivers/input/keyboard/Kconfig
index 28de965a08d5..c55230c4c344 100644
--- a/drivers/input/keyboard/Kconfig
+++ b/drivers/input/keyboard/Kconfig
@@ -782,6 +782,17 @@ config KEYBOARD_BCM
To compile this driver as a module, choose M here: the
module will be called bcm-keypad.

+config KEYBOARD_MTK_KPD
+ tristate "MediaTek Keypad Support"
+ depends on ARCH_MEDIATEK || COMPILE_TEST
+ select CONFIG_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 mtk-kpd.
+
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 1d689fdd5c00..6c9d852c377e 100644
--- a/drivers/input/keyboard/Makefile
+++ b/drivers/input/keyboard/Makefile
@@ -43,6 +43,7 @@ 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-$(CONFIG_KEYBOARD_MTK_KPD) += mtk-kpd.o
obj-$(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/mtk-kpd.c b/drivers/input/keyboard/mtk-kpd.c
new file mode 100644
index 000000000000..5123dbb00ad1
--- /dev/null
+++ b/drivers/input/keyboard/mtk-kpd.c
@@ -0,0 +1,201 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Copyright (C) 2019 MediaTek Inc.
+ * Author Terry Chang <terry.chang@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 "mtk-kpd"
+#define MTK_KPD_MEM 0x0004
+#define MTK_KPD_DEBOUNCE 0x0018
+#define MTK_KPD_DEBOUNCE_MASK GENMASK(13, 0)
+#define MTK_KPD_DEBOUNCE_MAX_US 256000
+#define MTK_KPD_NUM_MEMS 5
+#define MTK_KPD_NUM_BITS 136 /* 4*32+8 MEM5 only use 8 BITS */
+
+struct mtk_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 keypad_regmap_cfg = {
+ .reg_bits = 32,
+ .val_bits = 32,
+ .reg_stride = sizeof(u32),
+ .max_register = 36,
+};
+
+static irqreturn_t kpd_irq_handler(int irq, void *dev_id)
+{
+ struct mtk_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;
+
+ regmap_raw_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) {
+ /* 1: not pressed, 0: pressed */
+ pressed = !test_bit(bit_nr, new_state);
+ dev_dbg(&keypad->input_dev->dev, "%s",
+ pressed ? "pressed" : "released");
+
+ /* 32bit register only use low 16bit as keypad mem register */
+ code = keycode[bit_nr - 16 * (BITS_TO_U32(bit_nr) - 1)];
+
+ 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 kpd_clk_disable(void *data)
+{
+ clk_disable_unprepare(data);
+}
+
+static int kpd_pdrv_probe(struct platform_device *pdev)
+{
+ struct mtk_keypad *keypad;
+ unsigned int irq;
+ u32 debounce;
+ int ret;
+
+ 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,
+ &keypad_regmap_cfg);
+ if (IS_ERR(keypad->regmap)) {
+ dev_err(&pdev->dev,
+ "regmap init failed:%ld\n", PTR_ERR(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;
+
+ ret = matrix_keypad_parse_properties(&pdev->dev, &keypad->n_rows,
+ &keypad->n_cols);
+ if (ret) {
+ dev_err(&pdev->dev, "Failed to parse keypad params\n");
+ return ret;
+ }
+
+ if (device_property_read_u32(&pdev->dev, "mediatek,debounce-us",
+ &debounce))
+ debounce = 16000;
+
+ if (debounce > MTK_KPD_DEBOUNCE_MAX_US) {
+ dev_err(&pdev->dev, "Debounce time exceeds the maximum allowed time %dus\n",
+ MTK_KPD_DEBOUNCE_MAX_US);
+ return -EINVAL;
+ }
+
+ dev_dbg(&pdev->dev, "n_row=%d n_col=%d debounce=%d\n",
+ keypad->n_rows, keypad->n_cols, debounce);
+
+ ret = matrix_keypad_build_keymap(NULL, NULL,
+ keypad->n_rows,
+ keypad->n_cols,
+ NULL,
+ keypad->input_dev);
+ if (ret) {
+ dev_err(&pdev->dev, "Failed to build keymap\n");
+ return ret;
+ }
+
+ regmap_write(keypad->regmap, MTK_KPD_DEBOUNCE,
+ debounce * 32 / 1000 & MTK_KPD_DEBOUNCE_MASK);
+
+ keypad->clk = devm_clk_get(&pdev->dev, "kpd");
+ if (IS_ERR(keypad->clk))
+ return keypad->clk;
+
+ ret = clk_prepare_enable(keypad->clk);
+ if (ret) {
+ dev_err(&pdev->dev, "cannot prepare/enable keypad clock\n");
+ return ret;
+ }
+
+ ret = devm_add_action_or_reset(&pdev->dev, kpd_clk_disable,
+ keypad->clk);
+ if (ret)
+ return ret;
+
+ irq = platform_get_irq(pdev, 0);
+ if (irq < 0)
+ return irq;
+
+ ret = devm_request_threaded_irq(&pdev->dev, irq,
+ NULL, kpd_irq_handler, 0,
+ MTK_KPD_NAME, keypad);
+ if (ret) {
+ dev_err(&pdev->dev, "Failed to request IRQ#%d:%d\n",
+ irq, ret);
+ return ret;
+ }
+
+ ret = input_register_device(keypad->input_dev);
+ if (ret)
+ dev_err(&pdev->dev, "Failed to register device\n");
+
+ return ret;
+}
+
+static const struct of_device_id kpd_of_match[] = {
+ { .compatible = "mediatek,mt6779-keypad" },
+ { .compatible = "mediatek,mt6873-keypad" },
+ { /* sentinel */ }
+};
+
+static struct platform_driver kpd_pdrv = {
+ .probe = kpd_pdrv_probe,
+ .driver = {
+ .name = MTK_KPD_NAME,
+ .of_match_table = kpd_of_match,
+ },
+};
+module_platform_driver(kpd_pdrv);
+
+MODULE_AUTHOR("Mediatek Corporation");
+MODULE_DESCRIPTION("MTK Keypad (KPD) Driver");
+MODULE_LICENSE("GPL");