Adds a new keypad driver for the MA35D1 platform. The driver supports key scanning and interrupt handling. Signed-off-by: Ming-Jen Chen <mjchen0829@xxxxxxxxx> --- drivers/input/keyboard/Kconfig | 10 + drivers/input/keyboard/Makefile | 1 + drivers/input/keyboard/ma35d1_keypad.c | 386 +++++++++++++++++++++++++ 3 files changed, 397 insertions(+) create mode 100644 drivers/input/keyboard/ma35d1_keypad.c diff --git a/drivers/input/keyboard/Kconfig b/drivers/input/keyboard/Kconfig index 721ab69e84ac..d7c0d0f4a88d 100644 --- a/drivers/input/keyboard/Kconfig +++ b/drivers/input/keyboard/Kconfig @@ -797,4 +797,14 @@ config KEYBOARD_CYPRESS_SF To compile this driver as a module, choose M here: the module will be called cypress-sf. +config KEYBOARD_MA35D1 + tristate "Nuvoton MA35D1 keypad driver" + depends on ARCH_MA35 || COMPILE_TEST + select INPUT_MATRIXKMAP + help + Say Y here if you want to use Nuvoton MA35D1 keypad. + + To compile this driver as a module, choose M here: the + module will be called ma35d1-keypad. + endif diff --git a/drivers/input/keyboard/Makefile b/drivers/input/keyboard/Makefile index 1e0721c30709..9b858cdd1b6b 100644 --- a/drivers/input/keyboard/Makefile +++ b/drivers/input/keyboard/Makefile @@ -70,3 +70,4 @@ obj-$(CONFIG_KEYBOARD_TEGRA) += tegra-kbc.o obj-$(CONFIG_KEYBOARD_TM2_TOUCHKEY) += tm2-touchkey.o obj-$(CONFIG_KEYBOARD_TWL4030) += twl4030_keypad.o obj-$(CONFIG_KEYBOARD_XTKBD) += xtkbd.o +obj-$(CONFIG_KEYBOARD_MA35D1) += ma35d1_keypad.o diff --git a/drivers/input/keyboard/ma35d1_keypad.c b/drivers/input/keyboard/ma35d1_keypad.c new file mode 100644 index 000000000000..8410f7dd2e56 --- /dev/null +++ b/drivers/input/keyboard/ma35d1_keypad.c @@ -0,0 +1,386 @@ +// SPDX-License-Identifier: GPL-2.0+ +/* + * MA35D1 keypad driver + * Copyright (C) 2024 Nuvoton Technology Corp. + */ + +#include <linux/bitfield.h> +#include <linux/interrupt.h> +#include <linux/input.h> +#include <linux/platform_device.h> +#include <linux/input/matrix_keypad.h> +#include <linux/clk.h> +#include <linux/of.h> +#include <linux/bitops.h> +#include <linux/pm_wakeirq.h> + +/* Keypad Interface Registers */ +#define KPI_CONF 0x00 +#define KPI_3KCONF 0x04 +#define KPI_STATUS 0x08 +#define KPI_RSTC 0x0C +#define KPI_KEST 0x10 +#define KPI_KPE0 0x18 +#define KPI_KPE1 0x1C +#define KPI_KRE0 0x20 +#define KPI_KRE1 0x24 +#define KPI_PRESCALDIV 0x28 + +/* KPI_CONF - Keypad Configuration Register */ +#define KROW GENMASK(30, 28) /* Keypad Matrix ROW number */ +#define KCOL GENMASK(26, 24) /* Keypad Matrix COL Number */ +#define DB_CLKSEL GENMASK(19, 16) /* De-bounce sampling cycle selection */ +#define PRESCALE GENMASK(15, 8) /* Row Scan Cycle Pre-scale Value */ +#define WAKEUP BIT(5) /* Lower Power Wakeup Enable */ +#define INTEN BIT(3) /* Key Interrupt Enable Control */ +#define RKINTEN BIT(2) /* Release Key Interrupt Enable */ +#define PKINTEN BIT(1) /* Press Key Interrupt Enable Control */ +#define ENKP BIT(0) /* Keypad Scan Enable */ + +/* KPI_STATUS - Keypad Status Register */ +#define PKEY_INT BIT(4) /* Press key interrupt */ +#define RKEY_INT BIT(3) /* Release key interrupt */ +#define KEY_INT BIT(2) /* Key Interrupt */ +#define RST_3KEY BIT(1) /* 3-Keys Reset Flag */ +#define PDWAKE BIT(0) /* Power Down Wakeup Flag */ + +#define KEY_EVENT_BITS 64 + +#define NUM_SETTINGS 12 +#define PRE_SCALE_MAX 256 +#define PRE_SCALE_DIV_MAX 256 + +static const unsigned int debounce_values[NUM_SETTINGS] = { + 0, 8, 16, 32, 64, 128, 256, 512, 1024, 2048, 4096, 8192 +}; + +static const unsigned int debounce_register[NUM_SETTINGS] = { + 0x0, 0x3, 0x4, 0x5, 0x6, 0x7, 0x8, 0x9, 0xA, 0xB, 0xC, 0xD +}; + +struct ma35d1_keypad { + struct clk *clk; + struct input_dev *input_dev; + void __iomem *mmio_base; + int irq; + u32 kpi_row; + u32 kpi_col; + u32 debounce_val; + u32 pre_scale; + u32 pre_scale_div; +}; + +static void ma35d1_keypad_scan_matrix(struct ma35d1_keypad *keypad, unsigned int status) +{ + struct input_dev *input_dev = keypad->input_dev; + u32 row_shift = get_count_order(keypad->kpi_col); + u32 *keymap = input_dev->keycode; + u32 code, key, index; + u32 key_event[4]; + u64 pressed_keys = 0, released_keys = 0; + + /* Read key event status */ + key_event[0] = readl(keypad->mmio_base + KPI_KPE0); + key_event[1] = readl(keypad->mmio_base + KPI_KPE1); + key_event[2] = readl(keypad->mmio_base + KPI_KRE0); + key_event[3] = readl(keypad->mmio_base + KPI_KRE1); + + /* Clear key event status */ + writel(key_event[0], (keypad->mmio_base + KPI_KPE0)); + writel(key_event[1], (keypad->mmio_base + KPI_KPE1)); + writel(key_event[2], (keypad->mmio_base + KPI_KRE0)); + writel(key_event[3], (keypad->mmio_base + KPI_KRE1)); + + pressed_keys = key_event[0] | ((u64)key_event[1] << 32); + released_keys = key_event[2] | ((u64)key_event[3] << 32); + + /* Process pressed keys */ + for_each_set_bit(index, (const unsigned long *)&pressed_keys, KEY_EVENT_BITS) { + code = MATRIX_SCAN_CODE(index / 8, (index % 8), row_shift); + key = keymap[code]; + + input_event(input_dev, EV_MSC, MSC_SCAN, code); + input_report_key(input_dev, key, 1); + } + + /* Process released keys */ + for_each_set_bit(index, (const unsigned long *)&released_keys, KEY_EVENT_BITS) { + code = MATRIX_SCAN_CODE(index / 8, (index % 8), row_shift); + key = keymap[code]; + + input_event(input_dev, EV_MSC, MSC_SCAN, code); + input_report_key(input_dev, key, 0); + } + + input_sync(input_dev); +} + +static irqreturn_t ma35d1_keypad_interrupt(int irq, void *dev_id) +{ + struct ma35d1_keypad *keypad = dev_id; + unsigned int kstatus; + + kstatus = readl(keypad->mmio_base + KPI_STATUS); + + if (kstatus & (PKEY_INT | RKEY_INT)) { + ma35d1_keypad_scan_matrix(keypad, kstatus); + } else { + if (kstatus & PDWAKE) + writel(PDWAKE, (keypad->mmio_base + KPI_STATUS)); + } + + return IRQ_HANDLED; +} + +static int ma35d1_keypad_open(struct input_dev *dev) +{ + struct ma35d1_keypad *keypad = input_get_drvdata(dev); + u32 val, config; + + val = RKINTEN | PKINTEN | INTEN | ENKP; + val |= FIELD_PREP(KCOL, (keypad->kpi_col - 1)) | FIELD_PREP(KROW, (keypad->kpi_row - 1)); + + config = FIELD_PREP(PRESCALE, (keypad->pre_scale - 1)) | + FIELD_PREP(DB_CLKSEL, keypad->debounce_val); + + val |= config; + + writel(val, keypad->mmio_base + KPI_CONF); + writel((keypad->pre_scale_div - 1), keypad->mmio_base + KPI_PRESCALDIV); + + return 0; +} + +static void ma35d1_keypad_close(struct input_dev *dev) +{ + struct ma35d1_keypad *keypad = input_get_drvdata(dev); + u32 val; + + val = readl(keypad->mmio_base + KPI_KPE0) & ~ENKP; + writel(val, keypad->mmio_base + KPI_CONF); +} + +static int ma35d1_parse_dt(struct ma35d1_keypad *keypad, u32 debounce_ms, u32 scan_interval) +{ + u32 clk_rate = clk_get_rate(keypad->clk); + u32 min_diff = debounce_values[NUM_SETTINGS]; + u32 i, clk_cycles, diff, p, d; + u32 best_diff = 0xffff; + + /* Calculate debounce cycles */ + clk_cycles = clk_rate * debounce_ms / 1000; + + keypad->debounce_val = debounce_register[NUM_SETTINGS]; + + for (i = 0; i < NUM_SETTINGS; i++) { + diff = abs((s32)(clk_cycles - debounce_values[i])); + if (diff < min_diff) { + min_diff = diff; + keypad->debounce_val = debounce_register[i]; + } + } + + /* Find scan time setting */ + clk_cycles = clk_rate * scan_interval / 1000; + clk_cycles = clk_cycles / keypad->kpi_row; + + if (clk_cycles == 0) { + keypad->pre_scale = 1; + keypad->pre_scale_div = 1; + } else if (clk_cycles >= PRE_SCALE_MAX * PRE_SCALE_DIV_MAX) { + keypad->pre_scale = PRE_SCALE_MAX; + keypad->pre_scale_div = PRE_SCALE_DIV_MAX; + } else { + for (p = 1; p <= PRE_SCALE_MAX; p++) { + d = (clk_cycles + (p / 2)) / p; + + if (d > 0 && d <= PRE_SCALE_DIV_MAX) { + diff = abs((s32)(p * d) - clk_cycles); + + if (diff < best_diff) { + best_diff = diff; + keypad->pre_scale = p; + keypad->pre_scale_div = d; + + if (diff == 0) + break; + } + } + } + } + + /* + * Hardware Limitation: + * Due to the hardware design, the keypad debounce time must not exceed + * half of the row scan time. + * + * The row scan time is determined by the formula: + * Row Scan Time = pre_scale * pre_scale_div + * + * Therefore, the debounce time must satisfy the following condition: + * Debounce Time < (Row Scan Time / 2) + * + * For example: + * If pre_scale = 64, pre_scale_div = 32, + * then Row Scan Time = 64 * 32 = 2048 keypad clock. + * Hence, the maximum allowable debounce time is 1024 keypad clock. + */ + + if (keypad->debounce_val >= (keypad->pre_scale * keypad->pre_scale_div) / 2) + return -EINVAL; + + return 0; +} + +static int ma35d1_keypad_probe(struct platform_device *pdev) +{ + struct ma35d1_keypad *keypad; + struct input_dev *input_dev; + struct resource *res; + u32 debounce, scan_interval; + int error = 0; + + keypad = devm_kzalloc(&pdev->dev, sizeof(*keypad), GFP_KERNEL); + if (!keypad) + return -ENOMEM; + + input_dev = devm_input_allocate_device(&pdev->dev); + if (!input_dev) + return -ENOMEM; + + res = platform_get_resource(pdev, IORESOURCE_MEM, 0); + if (!res) + return -ENODEV; + + keypad->mmio_base = devm_ioremap_resource(&pdev->dev, res); + if (IS_ERR(keypad->mmio_base)) + return dev_err_probe(&pdev->dev, PTR_ERR(keypad->mmio_base), + "failed to remap I/O memor\n"); + + keypad->irq = platform_get_irq(pdev, 0); + if (keypad->irq < 0) { + dev_err(&pdev->dev, "failed to get IRQ\n"); + return keypad->irq; + } + + keypad->clk = devm_clk_get_enabled(&pdev->dev, NULL); + if (IS_ERR(keypad->clk)) + return dev_err_probe(&pdev->dev, PTR_ERR(keypad->clk), "failed to get core clk\n"); + + error = matrix_keypad_parse_properties(&pdev->dev, &keypad->kpi_row, &keypad->kpi_col); + if (error) { + dev_err(&pdev->dev, "failed to parse keypad params\n"); + return error; + } + + error = matrix_keypad_build_keymap(NULL, NULL, keypad->kpi_row, keypad->kpi_col, + NULL, input_dev); + if (error) { + dev_err(&pdev->dev, "failed to build keymap\n"); + return error; + } + + keypad->input_dev = input_dev; + input_dev->name = pdev->name; + input_dev->id.bustype = BUS_HOST; + input_dev->open = ma35d1_keypad_open; + input_dev->close = ma35d1_keypad_close; + input_dev->dev.parent = &pdev->dev; + + error = device_property_read_u32(&pdev->dev, "debounce-delay-ms", &debounce); + if (error) { + dev_err(&pdev->dev, "failed to acquire 'debounce-delay-ms'\n"); + return error; + } + + error = device_property_read_u32(&pdev->dev, "scan-interval-ms", &scan_interval); + if (error) { + dev_err(&pdev->dev, "failed to acquire 'scan-interval'\n"); + return error; + } + + error = ma35d1_parse_dt(keypad, debounce, scan_interval); + if (error) { + dev_err(&pdev->dev, "keypad dt params error\n"); + return error; + } + + __set_bit(EV_REP, input_dev->evbit); + input_set_drvdata(input_dev, keypad); + input_set_capability(input_dev, EV_MSC, MSC_SCAN); + + error = devm_request_irq(&pdev->dev, keypad->irq, ma35d1_keypad_interrupt, + IRQF_NO_SUSPEND, pdev->name, keypad); + if (error) { + dev_err(&pdev->dev, "failed to request IRQ\n"); + return error; + } + + platform_set_drvdata(pdev, keypad); + device_init_wakeup(&pdev->dev, 1); + + error = dev_pm_set_wake_irq(&pdev->dev, keypad->irq); + if (error) { + dev_err(&pdev->dev, "failed to enable irq wake\n"); + return error; + } + + error = input_register_device(input_dev); + if (error) { + dev_err(&pdev->dev, "failed to register input device\n"); + return error; + } + + return 0; +} + +static void ma35d1_keypad_remove(struct platform_device *pdev) +{ + struct ma35d1_keypad *keypad = platform_get_drvdata(pdev); + + input_unregister_device(keypad->input_dev); +} + +static int ma35d1_keypad_suspend(struct device *dev) +{ + struct ma35d1_keypad *keypad = dev_get_drvdata(dev); + + if (device_may_wakeup(dev)) + writel(readl(keypad->mmio_base + KPI_CONF) | WAKEUP, keypad->mmio_base + KPI_CONF); + + return 0; +} + +static int ma35d1_keypad_resume(struct device *dev) +{ + struct ma35d1_keypad *keypad = dev_get_drvdata(dev); + + if (device_may_wakeup(dev)) + writel(readl(keypad->mmio_base + KPI_CONF) & ~(WAKEUP), + keypad->mmio_base + KPI_CONF); + + return 0; +} + +static DEFINE_SIMPLE_DEV_PM_OPS(ma35d1_pm_ops, ma35d1_keypad_suspend, ma35d1_keypad_resume); + +static const struct of_device_id ma35d1_kpi_of_match[] = { + { .compatible = "nuvoton,ma35d1-kpi"}, + {}, +}; +MODULE_DEVICE_TABLE(of, ma35d1_kpi_of_match); + +static struct platform_driver ma35d1_keypad_driver = { + .probe = ma35d1_keypad_probe, + .remove = ma35d1_keypad_remove, + .driver = { + .name = "ma35d1-kpi", + .pm = pm_sleep_ptr(&ma35d1_pm_ops), + .of_match_table = ma35d1_kpi_of_match, + }, +}; +module_platform_driver(ma35d1_keypad_driver); + +MODULE_AUTHOR("Ming-Jen Chen"); +MODULE_DESCRIPTION("MA35D1 Keypad Driver"); +MODULE_LICENSE("GPL"); -- 2.25.1