1 files changed, 458 insertions, 0 deletions
diff --git a/drivers/input/keyboard/twl4030_keypad.c b/drivers/input/keyboard/twl4030_keypad.c
new file mode 100644
index 000000000..77e0743a3
--- /dev/null
+++ b/drivers/input/keyboard/twl4030_keypad.c
@@ -0,0 +1,458 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
+/*
+ * twl4030_keypad.c - driver for 8x8 keypad controller in twl4030 chips
+ *
+ * Copyright (C) 2007 Texas Instruments, Inc.
+ * Copyright (C) 2008 Nokia Corporation
+ *
+ * Code re-written for 2430SDP by:
+ * Syed Mohammed Khasim <x0khasim@ti.com>
+ *
+ * Initial Code:
+ * Manjunatha G K <manjugk@ti.com>
+ */
+
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/interrupt.h>
+#include <linux/input.h>
+#include <linux/platform_device.h>
+#include <linux/mfd/twl.h>
+#include <linux/slab.h>
+#include <linux/of.h>
+
+/*
+ * The TWL4030 family chips include a keypad controller that supports
+ * up to an 8x8 switch matrix.  The controller can issue system wakeup
+ * events, since it uses only the always-on 32KiHz oscillator, and has
+ * an internal state machine that decodes pressed keys, including
+ * multi-key combinations.
+ *
+ * This driver lets boards define what keycodes they wish to report for
+ * which scancodes, as part of the "struct twl4030_keypad_data" used in
+ * the probe() routine.
+ *
+ * See the TPS65950 documentation; that's the general availability
+ * version of the TWL5030 second generation part.
+ */
+#define TWL4030_MAX_ROWS	8	/* TWL4030 hard limit */
+#define TWL4030_MAX_COLS	8
+/*
+ * Note that we add space for an extra column so that we can handle
+ * row lines connected to the gnd (see twl4030_col_xlate()).
+ */
+#define TWL4030_ROW_SHIFT	4
+#define TWL4030_KEYMAP_SIZE	(TWL4030_MAX_ROWS << TWL4030_ROW_SHIFT)
+
+struct twl4030_keypad {
+	unsigned short	keymap[TWL4030_KEYMAP_SIZE];
+	u16		kp_state[TWL4030_MAX_ROWS];
+	bool		autorepeat;
+	unsigned int	n_rows;
+	unsigned int	n_cols;
+	int		irq;
+
+	struct device *dbg_dev;
+	struct input_dev *input;
+};
+
+/*----------------------------------------------------------------------*/
+
+/* arbitrary prescaler value 0..7 */
+#define PTV_PRESCALER			4
+
+/* Register Offsets */
+#define KEYP_CTRL			0x00
+#define KEYP_DEB			0x01
+#define KEYP_LONG_KEY			0x02
+#define KEYP_LK_PTV			0x03
+#define KEYP_TIMEOUT_L			0x04
+#define KEYP_TIMEOUT_H			0x05
+#define KEYP_KBC			0x06
+#define KEYP_KBR			0x07
+#define KEYP_SMS			0x08
+#define KEYP_FULL_CODE_7_0		0x09	/* row 0 column status */
+#define KEYP_FULL_CODE_15_8		0x0a	/* ... row 1 ... */
+#define KEYP_FULL_CODE_23_16		0x0b
+#define KEYP_FULL_CODE_31_24		0x0c
+#define KEYP_FULL_CODE_39_32		0x0d
+#define KEYP_FULL_CODE_47_40		0x0e
+#define KEYP_FULL_CODE_55_48		0x0f
+#define KEYP_FULL_CODE_63_56		0x10
+#define KEYP_ISR1			0x11
+#define KEYP_IMR1			0x12
+#define KEYP_ISR2			0x13
+#define KEYP_IMR2			0x14
+#define KEYP_SIR			0x15
+#define KEYP_EDR			0x16	/* edge triggers */
+#define KEYP_SIH_CTRL			0x17
+
+/* KEYP_CTRL_REG Fields */
+#define KEYP_CTRL_SOFT_NRST		BIT(0)
+#define KEYP_CTRL_SOFTMODEN		BIT(1)
+#define KEYP_CTRL_LK_EN			BIT(2)
+#define KEYP_CTRL_TOE_EN		BIT(3)
+#define KEYP_CTRL_TOLE_EN		BIT(4)
+#define KEYP_CTRL_RP_EN			BIT(5)
+#define KEYP_CTRL_KBD_ON		BIT(6)
+
+/* KEYP_DEB, KEYP_LONG_KEY, KEYP_TIMEOUT_x*/
+#define KEYP_PERIOD_US(t, prescale)	((t) / (31 << ((prescale) + 1)) - 1)
+
+/* KEYP_LK_PTV_REG Fields */
+#define KEYP_LK_PTV_PTV_SHIFT		5
+
+/* KEYP_{IMR,ISR,SIR} Fields */
+#define KEYP_IMR1_MIS			BIT(3)
+#define KEYP_IMR1_TO			BIT(2)
+#define KEYP_IMR1_LK			BIT(1)
+#define KEYP_IMR1_KP			BIT(0)
+
+/* KEYP_EDR Fields */
+#define KEYP_EDR_KP_FALLING		0x01
+#define KEYP_EDR_KP_RISING		0x02
+#define KEYP_EDR_KP_BOTH		0x03
+#define KEYP_EDR_LK_FALLING		0x04
+#define KEYP_EDR_LK_RISING		0x08
+#define KEYP_EDR_TO_FALLING		0x10
+#define KEYP_EDR_TO_RISING		0x20
+#define KEYP_EDR_MIS_FALLING		0x40
+#define KEYP_EDR_MIS_RISING		0x80
+
+
+/*----------------------------------------------------------------------*/
+
+static int twl4030_kpread(struct twl4030_keypad *kp,
+		u8 *data, u32 reg, u8 num_bytes)
+{
+	int ret = twl_i2c_read(TWL4030_MODULE_KEYPAD, data, reg, num_bytes);
+
+	if (ret < 0)
+		dev_warn(kp->dbg_dev,
+			"Couldn't read TWL4030: %X - ret %d[%x]\n",
+			 reg, ret, ret);
+
+	return ret;
+}
+
+static int twl4030_kpwrite_u8(struct twl4030_keypad *kp, u8 data, u32 reg)
+{
+	int ret = twl_i2c_write_u8(TWL4030_MODULE_KEYPAD, data, reg);
+
+	if (ret < 0)
+		dev_warn(kp->dbg_dev,
+			"Could not write TWL4030: %X - ret %d[%x]\n",
+			 reg, ret, ret);
+
+	return ret;
+}
+
+static inline u16 twl4030_col_xlate(struct twl4030_keypad *kp, u8 col)
+{
+	/*
+	 * If all bits in a row are active for all columns then
+	 * we have that row line connected to gnd. Mark this
+	 * key on as if it was on matrix position n_cols (i.e.
+	 * one higher than the size of the matrix).
+	 */
+	if (col == 0xFF)
+		return 1 << kp->n_cols;
+	else
+		return col & ((1 << kp->n_cols) - 1);
+}
+
+static int twl4030_read_kp_matrix_state(struct twl4030_keypad *kp, u16 *state)
+{
+	u8 new_state[TWL4030_MAX_ROWS];
+	int row;
+	int ret = twl4030_kpread(kp, new_state,
+				 KEYP_FULL_CODE_7_0, kp->n_rows);
+	if (ret >= 0)
+		for (row = 0; row < kp->n_rows; row++)
+			state[row] = twl4030_col_xlate(kp, new_state[row]);
+
+	return ret;
+}
+
+static bool twl4030_is_in_ghost_state(struct twl4030_keypad *kp, u16 *key_state)
+{
+	int i;
+	u16 check = 0;
+
+	for (i = 0; i < kp->n_rows; i++) {
+		u16 col = key_state[i];
+
+		if ((col & check) && hweight16(col) > 1)
+			return true;
+
+		check |= col;
+	}
+
+	return false;
+}
+
+static void twl4030_kp_scan(struct twl4030_keypad *kp, bool release_all)
+{
+	struct input_dev *input = kp->input;
+	u16 new_state[TWL4030_MAX_ROWS];
+	int col, row;
+
+	if (release_all) {
+		memset(new_state, 0, sizeof(new_state));
+	} else {
+		/* check for any changes */
+		int ret = twl4030_read_kp_matrix_state(kp, new_state);
+
+		if (ret < 0)	/* panic ... */
+			return;
+
+		if (twl4030_is_in_ghost_state(kp, new_state))
+			return;
+	}
+
+	/* check for changes and print those */
+	for (row = 0; row < kp->n_rows; row++) {
+		int changed = new_state[row] ^ kp->kp_state[row];
+
+		if (!changed)
+			continue;
+
+		/* Extra column handles "all gnd" rows */
+		for (col = 0; col < kp->n_cols + 1; col++) {
+			int code;
+
+			if (!(changed & (1 << col)))
+				continue;
+
+			dev_dbg(kp->dbg_dev, "key [%d:%d] %s\n", row, col,
+				(new_state[row] & (1 << col)) ?
+				"press" : "release");
+
+			code = MATRIX_SCAN_CODE(row, col, TWL4030_ROW_SHIFT);
+			input_event(input, EV_MSC, MSC_SCAN, code);
+			input_report_key(input, kp->keymap[code],
+					 new_state[row] & (1 << col));
+		}
+		kp->kp_state[row] = new_state[row];
+	}
+	input_sync(input);
+}
+
+/*
+ * Keypad interrupt handler
+ */
+static irqreturn_t do_kp_irq(int irq, void *_kp)
+{
+	struct twl4030_keypad *kp = _kp;
+	u8 reg;
+	int ret;
+
+	/* Read & Clear TWL4030 pending interrupt */
+	ret = twl4030_kpread(kp, &reg, KEYP_ISR1, 1);
+
+	/*
+	 * Release all keys if I2C has gone bad or
+	 * the KEYP has gone to idle state.
+	 */
+	if (ret >= 0 && (reg & KEYP_IMR1_KP))
+		twl4030_kp_scan(kp, false);
+	else
+		twl4030_kp_scan(kp, true);
+
+	return IRQ_HANDLED;
+}
+
+static int twl4030_kp_program(struct twl4030_keypad *kp)
+{
+	u8 reg;
+	int i;
+
+	/* Enable controller, with hardware decoding but not autorepeat */
+	reg = KEYP_CTRL_SOFT_NRST | KEYP_CTRL_SOFTMODEN
+		| KEYP_CTRL_TOE_EN | KEYP_CTRL_KBD_ON;
+	if (twl4030_kpwrite_u8(kp, reg, KEYP_CTRL) < 0)
+		return -EIO;
+
+	/*
+	 * NOTE: we could use sih_setup() here to package keypad
+	 * event sources as four different IRQs ... but we don't.
+	 */
+
+	/* Enable TO rising and KP rising and falling edge detection */
+	reg = KEYP_EDR_KP_BOTH | KEYP_EDR_TO_RISING;
+	if (twl4030_kpwrite_u8(kp, reg, KEYP_EDR) < 0)
+		return -EIO;
+
+	/* Set PTV prescaler Field */
+	reg = (PTV_PRESCALER << KEYP_LK_PTV_PTV_SHIFT);
+	if (twl4030_kpwrite_u8(kp, reg, KEYP_LK_PTV) < 0)
+		return -EIO;
+
+	/* Set key debounce time to 20 ms */
+	i = KEYP_PERIOD_US(20000, PTV_PRESCALER);
+	if (twl4030_kpwrite_u8(kp, i, KEYP_DEB) < 0)
+		return -EIO;
+
+	/* Set timeout period to 200 ms */
+	i = KEYP_PERIOD_US(200000, PTV_PRESCALER);
+	if (twl4030_kpwrite_u8(kp, (i & 0xFF), KEYP_TIMEOUT_L) < 0)
+		return -EIO;
+
+	if (twl4030_kpwrite_u8(kp, (i >> 8), KEYP_TIMEOUT_H) < 0)
+		return -EIO;
+
+	/*
+	 * Enable Clear-on-Read; disable remembering events that fire
+	 * after the IRQ but before our handler acks (reads) them.
+	 */
+	reg = TWL4030_SIH_CTRL_COR_MASK | TWL4030_SIH_CTRL_PENDDIS_MASK;
+	if (twl4030_kpwrite_u8(kp, reg, KEYP_SIH_CTRL) < 0)
+		return -EIO;
+
+	/* initialize key state; irqs update it from here on */
+	if (twl4030_read_kp_matrix_state(kp, kp->kp_state) < 0)
+		return -EIO;
+
+	return 0;
+}
+
+/*
+ * Registers keypad device with input subsystem
+ * and configures TWL4030 keypad registers
+ */
+static int twl4030_kp_probe(struct platform_device *pdev)
+{
+	struct twl4030_keypad_data *pdata = dev_get_platdata(&pdev->dev);
+	const struct matrix_keymap_data *keymap_data = NULL;
+	struct twl4030_keypad *kp;
+	struct input_dev *input;
+	u8 reg;
+	int error;
+
+	kp = devm_kzalloc(&pdev->dev, sizeof(*kp), GFP_KERNEL);
+	if (!kp)
+		return -ENOMEM;
+
+	input = devm_input_allocate_device(&pdev->dev);
+	if (!input)
+		return -ENOMEM;
+
+	/* get the debug device */
+	kp->dbg_dev		= &pdev->dev;
+	kp->input		= input;
+
+	/* setup input device */
+	input->name		= "TWL4030 Keypad";
+	input->phys		= "twl4030_keypad/input0";
+
+	input->id.bustype	= BUS_HOST;
+	input->id.vendor	= 0x0001;
+	input->id.product	= 0x0001;
+	input->id.version	= 0x0003;
+
+	if (pdata) {
+		if (!pdata->rows || !pdata->cols || !pdata->keymap_data) {
+			dev_err(&pdev->dev, "Missing platform_data\n");
+			return -EINVAL;
+		}
+
+		kp->n_rows = pdata->rows;
+		kp->n_cols = pdata->cols;
+		kp->autorepeat = pdata->rep;
+		keymap_data = pdata->keymap_data;
+	} else {
+		error = matrix_keypad_parse_properties(&pdev->dev, &kp->n_rows,
+						       &kp->n_cols);
+		if (error)
+			return error;
+
+		kp->autorepeat = true;
+	}
+
+	if (kp->n_rows > TWL4030_MAX_ROWS || kp->n_cols > TWL4030_MAX_COLS) {
+		dev_err(&pdev->dev,
+			"Invalid rows/cols amount specified in platform/devicetree data\n");
+		return -EINVAL;
+	}
+
+	kp->irq = platform_get_irq(pdev, 0);
+	if (kp->irq < 0)
+		return kp->irq;
+
+	error = matrix_keypad_build_keymap(keymap_data, NULL,
+					   TWL4030_MAX_ROWS,
+					   1 << TWL4030_ROW_SHIFT,
+					   kp->keymap, input);
+	if (error) {
+		dev_err(kp->dbg_dev, "Failed to build keymap\n");
+		return error;
+	}
+
+	input_set_capability(input, EV_MSC, MSC_SCAN);
+	/* Enable auto repeat feature of Linux input subsystem */
+	if (kp->autorepeat)
+		__set_bit(EV_REP, input->evbit);
+
+	error = input_register_device(input);
+	if (error) {
+		dev_err(kp->dbg_dev,
+			"Unable to register twl4030 keypad device\n");
+		return error;
+	}
+
+	error = twl4030_kp_program(kp);
+	if (error)
+		return error;
+
+	/*
+	 * This ISR will always execute in kernel thread context because of
+	 * the need to access the TWL4030 over the I2C bus.
+	 *
+	 * NOTE:  we assume this host is wired to TWL4040 INT1, not INT2 ...
+	 */
+	error = devm_request_threaded_irq(&pdev->dev, kp->irq, NULL, do_kp_irq,
+					  0, pdev->name, kp);
+	if (error) {
+		dev_info(kp->dbg_dev, "request_irq failed for irq no=%d: %d\n",
+			kp->irq, error);
+		return error;
+	}
+
+	/* Enable KP and TO interrupts now. */
+	reg = (u8) ~(KEYP_IMR1_KP | KEYP_IMR1_TO);
+	if (twl4030_kpwrite_u8(kp, reg, KEYP_IMR1)) {
+		/* mask all events - we don't care about the result */
+		(void) twl4030_kpwrite_u8(kp, 0xff, KEYP_IMR1);
+		return -EIO;
+	}
+
+	return 0;
+}
+
+#ifdef CONFIG_OF
+static const struct of_device_id twl4030_keypad_dt_match_table[] = {
+	{ .compatible = "ti,twl4030-keypad" },
+	{},
+};
+MODULE_DEVICE_TABLE(of, twl4030_keypad_dt_match_table);
+#endif
+
+/*
+ * NOTE: twl4030 are multi-function devices connected via I2C.
+ * So this device is a child of an I2C parent, thus it needs to
+ * support unplug/replug (which most platform devices don't).
+ */
+
+static struct platform_driver twl4030_kp_driver = {
+	.probe		= twl4030_kp_probe,
+	.driver		= {
+		.name	= "twl4030_keypad",
+		.of_match_table = of_match_ptr(twl4030_keypad_dt_match_table),
+	},
+};
+module_platform_driver(twl4030_kp_driver);
+
+MODULE_AUTHOR("Texas Instruments");
+MODULE_DESCRIPTION("TWL4030 Keypad Driver");
+MODULE_LICENSE("GPL");
+MODULE_ALIAS("platform:twl4030_keypad");