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-rw-r--r--drivers/input/keyboard/twl4030_keypad.c458
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");