[PATCH v5] input: MXC: add mxc-keypad driver to support the Keypad Port present in the mxc application processors family.
Alberto Panizzo
maramaopercheseimorto at gmail.com
Fri Jan 29 16:18:46 EST 2010
The MXC family of Application Processors is shipped with a Keypad Port
supported now by this driver.
The peripheral can control up to an 8x8 matrix key pad where all the scanning
procedure is done via software.
The hardware provide two interrupts: one for a key pressed (KDI) and one for
all key releases (KRI). There is also a simple circuit for glitch reduction
(said for synchronization) made by two series of 3 D-latches clocked by the
keypad-clock that stabilize the interrupts sources.
KDI and KRI are fired only if the respective conditions are maintained for at
last 4 keypad-clock cycle.
Since those circuits are poor for a correct debounce process (the keypad-clock
frequency is 32K and bounces longer than 94us are not masked) the driver,
when an interrupt arrive, sample the matrix with a period of 2ms until
for MXC_KEYPAD_SCANS_FOR_STABILITY (3) times the matrix result stable.
After reached the stability proper events are fired comparing the new and
previous stable state.
If any key are maintained pressed for a longer time the driver continue to
probe the matrix with a greater period (60ms) to catch possible multiple key
pressures without overloading the cpu.
This process ends when all keys are released.
This driver is tested to build in kernel or as a module and follow the
specification of Freescale Application processors:
i.MX25 i.MX27 i.MX31 i.MX35 i.MX51 especially tested on i.MX31.
Signed-off-by: Alberto Panizzo <maramaopercheseimorto at gmail.com>
---
Changes in v2:
-This driver completely apply to matrix_keypad interface.
-Rearranged remove procedure.
-Automated hardware configuration, based on matrix_keypad_data.
-Removed useless macro.
Changes in v3:
-Make use of timer API for interrupt management instead of threaded irq.
-Little fixes.
Changes in v4:
-Better error handling.
-Coding style fixes.
-Fix parameters of clk_get.
Changes in v5:
-Rework of debouncing process. Now it is the driver that decide when the
matrix is stable to check for events.
-No needs of particular platform data.
drivers/input/keyboard/Kconfig | 9 +
drivers/input/keyboard/Makefile | 1 +
drivers/input/keyboard/mxc_keypad.c | 569 +++++++++++++++++++++++++++++++++++
3 files changed, 579 insertions(+), 0 deletions(-)
create mode 100644 drivers/input/keyboard/mxc_keypad.c
diff --git a/drivers/input/keyboard/Kconfig b/drivers/input/keyboard/Kconfig
index 02c836e..2abdab3 100644
--- a/drivers/input/keyboard/Kconfig
+++ b/drivers/input/keyboard/Kconfig
@@ -292,6 +292,15 @@ config KEYBOARD_MAX7359
To compile this driver as a module, choose M here: the
module will be called max7359_keypad.
+config KEYBOARD_MXC
+ tristate "MXC keypad support"
+ depends on ARCH_MXC
+ help
+ Enable support for MXC keypad port.
+
+ To compile this driver as a module, choose M here: the
+ module will be called mxc_keypad.
+
config KEYBOARD_NEWTON
tristate "Newton keyboard"
select SERIO
diff --git a/drivers/input/keyboard/Makefile b/drivers/input/keyboard/Makefile
index 78654ef..0530b78 100644
--- a/drivers/input/keyboard/Makefile
+++ b/drivers/input/keyboard/Makefile
@@ -25,6 +25,7 @@ obj-$(CONFIG_KEYBOARD_LOCOMO) += locomokbd.o
obj-$(CONFIG_KEYBOARD_MAPLE) += maple_keyb.o
obj-$(CONFIG_KEYBOARD_MATRIX) += matrix_keypad.o
obj-$(CONFIG_KEYBOARD_MAX7359) += max7359_keypad.o
+obj-$(CONFIG_KEYBOARD_MXC) += mxc_keypad.o
obj-$(CONFIG_KEYBOARD_NEWTON) += newtonkbd.o
obj-$(CONFIG_KEYBOARD_OMAP) += omap-keypad.o
obj-$(CONFIG_KEYBOARD_OPENCORES) += opencores-kbd.o
diff --git a/drivers/input/keyboard/mxc_keypad.c b/drivers/input/keyboard/mxc_keypad.c
new file mode 100644
index 0000000..c8931c5
--- /dev/null
+++ b/drivers/input/keyboard/mxc_keypad.c
@@ -0,0 +1,569 @@
+/*
+ * Driver for the MXC keypad port.
+ * Copyright (C) 2009 Alberto Panizzo <maramaopercheseimorto at gmail.com>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ *
+ * >>Power management need to be implemented<<.
+ */
+
+#include <linux/clk.h>
+#include <linux/delay.h>
+#include <linux/device.h>
+#include <linux/err.h>
+#include <linux/init.h>
+#include <linux/input/matrix_keypad.h>
+#include <linux/interrupt.h>
+#include <linux/io.h>
+#include <linux/jiffies.h>
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/platform_device.h>
+#include <linux/timer.h>
+
+/*
+ * Keypad Controller registers (halfword)
+ */
+#define KPCR 0x00 /* Keypad Control Register */
+
+#define KPSR 0x02 /* Keypad Status Register */
+#define KBD_STAT_KPKD (0x1 << 0) /* Key Press Interrupt Status bit (w1c) */
+#define KBD_STAT_KPKR (0x1 << 1) /* Key Release Interrupt Status bit (w1c) */
+#define KBD_STAT_KDSC (0x1 << 2) /* Key Depress Synch Chain Status bit (w1c)*/
+#define KBD_STAT_KRSS (0x1 << 3) /* Key Release Synch Status bit (w1c)*/
+#define KBD_STAT_KDIE (0x1 << 8) /* Key Depress Interrupt Enable Status bit */
+#define KBD_STAT_KRIE (0x1 << 9) /* Key Release Interrupt Enable */
+#define KBD_STAT_KPPEN (0x1 << 10) /* Keypad Clock Enable */
+
+#define KDDR 0x04 /* Keypad Data Direction Register */
+#define KPDR 0x06 /* Keypad Data Register */
+
+#define MAX_MATRIX_KEY_ROWS 8
+#define MAX_MATRIX_KEY_COLS 8
+#define MATRIX_ROW_SHIFT 3
+
+#define MAX_MATRIX_KEY_NUM (MAX_MATRIX_KEY_ROWS * MAX_MATRIX_KEY_COLS)
+
+struct mxc_keypad {
+
+ struct clk *clk;
+ struct input_dev *input_dev;
+ void __iomem *mmio_base;
+
+ int irq;
+ struct timer_list check_matrix_timer;
+
+ /* The matrix is stable only if no changes are detected after
+ * MXC_KEYPAD_SCANS_FOR_STABILITY scans */
+#define MXC_KEYPAD_SCANS_FOR_STABILITY 3
+ int stable_count;
+
+ /* If true the driver is shutting down */
+ bool exit_flag;
+
+ /* Masks for enabled rows/cols */
+ unsigned short rows_en_mask;
+ unsigned short cols_en_mask;
+
+ unsigned short keycodes[MAX_MATRIX_KEY_NUM];
+
+ /* Matrix states:
+ * -stable: achieved after a complete debounce process.
+ * -unstable: used in the debouncing process. */
+ unsigned short matrix_stable_state[MAX_MATRIX_KEY_COLS];
+ unsigned short matrix_unstable_state[MAX_MATRIX_KEY_COLS];
+};
+
+/* Scan the matrix and return the new state in *matrix_volatile_state. */
+static void mxc_keypad_scan_matrix(struct mxc_keypad *keypad,
+ unsigned short *matrix_volatile_state)
+{
+ int col;
+ unsigned short reg_val;
+
+ for (col = 0; col < MAX_MATRIX_KEY_COLS; col++) {
+ if ((keypad->cols_en_mask & (1 << col)) == 0)
+ continue;
+ /* Discharge keypad capacitance:
+ * 2. write 1s on column data.
+ * 3. configure columns as totem-pole to discharge capacitance.
+ * 4. configure columns as open-drain.*/
+ reg_val = readw(keypad->mmio_base + KPDR);
+ reg_val |= 0xff00;
+ writew(reg_val, keypad->mmio_base + KPDR);
+
+ reg_val = readw(keypad->mmio_base + KPCR);
+ reg_val &= ~((keypad->cols_en_mask & 0xff) << 8);
+ writew(reg_val, keypad->mmio_base + KPCR);
+
+ udelay(2);
+
+ reg_val = readw(keypad->mmio_base + KPCR);
+ reg_val |= (keypad->cols_en_mask & 0xff) << 8;
+ writew(reg_val, keypad->mmio_base + KPCR);
+
+ /*
+ * 5. Write a single column to 0, others to 1.
+ * 6. Sample row inputs and save data.
+ * 7. Repeat steps 2 - 6 for remaining columns.
+ */
+ reg_val = readw(keypad->mmio_base + KPDR);
+ reg_val &= ~(1 << (8 + col));
+ writew(reg_val, keypad->mmio_base + KPDR);
+
+ /* Delay added to avoid propagating the 0 from column to row
+ * when scanning. */
+ udelay(5);
+
+ /* 1s in matrix_volatile_state[col] means key pressures
+ * throw data from non enabled rows. */
+ reg_val = readw(keypad->mmio_base + KPDR);
+ matrix_volatile_state[col] = (~reg_val) & keypad->rows_en_mask;
+ }
+
+ /* Return in standby mode:
+ * 9. write 0s to columns */
+ reg_val = readw(keypad->mmio_base + KPDR);
+ reg_val &= 0x00ff;
+ writew(reg_val, keypad->mmio_base + KPDR);
+}
+
+/* Compare the new matrix state (volatile) with the stable one stored in
+ * keypad->matrix_stable_state and fire events if changes are detected. */
+static void mxc_keypad_fire_events(struct mxc_keypad *keypad,
+ unsigned short *matrix_volatile_state)
+{
+ struct input_dev *input_dev = keypad->input_dev;
+ int row, col;
+
+ for (col = 0; col < MAX_MATRIX_KEY_COLS; col++) {
+ unsigned short bits_changed;
+ int code;
+
+ if ((keypad->cols_en_mask & (1 << col)) == 0)
+ continue; /* Column not enabled */
+
+ bits_changed = keypad->matrix_stable_state[col] ^
+ matrix_volatile_state[col];
+
+ if (bits_changed == 0)
+ continue; /* Column not contain changes */
+
+ for (row = 0; row < MAX_MATRIX_KEY_ROWS; row++) {
+ if ((keypad->rows_en_mask & (1 << row)) == 0)
+ continue; /* Row not enabled */
+ if ((bits_changed & (1 << row)) == 0)
+ continue; /* Row not contain changes */
+
+ code = MATRIX_SCAN_CODE(row, col, MATRIX_ROW_SHIFT);
+ input_event(input_dev, EV_MSC, MSC_SCAN, code);
+ input_report_key(input_dev, keypad->keycodes[code],
+ matrix_volatile_state[col] & (1 << row));
+ dev_dbg(&input_dev->dev, "Event code: %d, val: %d",
+ keypad->keycodes[code],
+ matrix_volatile_state[col] & (1 << row));
+ }
+ }
+ input_sync(input_dev);
+}
+
+/* mxc_keypad_check_for_events is the timer handler.
+ * It is executed in a non interruptible area of the kernel (Soft interrupt) */
+static void mxc_keypad_check_for_events(unsigned long data)
+{
+ struct mxc_keypad *keypad = (struct mxc_keypad *) data;
+ struct input_dev *input_dev = keypad->input_dev;
+ unsigned short matrix_volatile_state[MAX_MATRIX_KEY_COLS];
+ unsigned short reg_val;
+ bool state_changed, is_zero_matrix;
+ int i;
+
+ memset(matrix_volatile_state, 0, sizeof(matrix_volatile_state));
+
+ /* Before exit fire key release events. */
+ if (keypad->exit_flag) {
+ dev_dbg(&input_dev->dev, "%s: exiting.\n", __func__);
+ mxc_keypad_fire_events(keypad, matrix_volatile_state);
+ return;
+ }
+
+ mxc_keypad_scan_matrix(keypad, matrix_volatile_state);
+
+ state_changed = false;
+ for (i = 0; (i < MAX_MATRIX_KEY_COLS) && !state_changed; i++) {
+ if ((keypad->cols_en_mask & (1 << i)) == 0)
+ continue;
+
+ if (keypad->matrix_unstable_state[i] ^
+ matrix_volatile_state[i])
+ state_changed = true;
+ }
+
+ /* If the matrix state is changed from the previous scan
+ * (Re)Begin the debouncing process, saving the new state in
+ * keypad->matrix_unstable_state.
+ * else
+ * Increase the count of number of scans with a stable state.*/
+ if (state_changed) {
+ memcpy(keypad->matrix_unstable_state, matrix_volatile_state,
+ sizeof(matrix_volatile_state));
+ keypad->stable_count = 0;
+ } else
+ keypad->stable_count++;
+
+ /* If the matrix is not as stable as we want reschedule a matrix scan
+ * near in the future. */
+ if (keypad->stable_count < MXC_KEYPAD_SCANS_FOR_STABILITY) {
+ mod_timer(&keypad->check_matrix_timer,
+ jiffies + msecs_to_jiffies(2));
+ return;
+ }
+
+ /* If the matrix is stable as we need, fire the events and save the new
+ * stable state.
+ * Note, if the matrix is more stable (keypad->stable_count >
+ * MXC_KEYPAD_SCANS_FOR_STABILITY)all events are already fired.We are in
+ * the loop of multiple key pressure detection waiting for a change. */
+ if (keypad->stable_count == MXC_KEYPAD_SCANS_FOR_STABILITY) {
+ mxc_keypad_fire_events(keypad, matrix_volatile_state);
+
+ memcpy(keypad->matrix_stable_state, matrix_volatile_state,
+ sizeof(matrix_volatile_state));
+ }
+
+ is_zero_matrix = true;
+ for (i = 0; (i < MAX_MATRIX_KEY_COLS) && is_zero_matrix; i++)
+ if (matrix_volatile_state[i] != 0)
+ is_zero_matrix = false;
+
+
+ if (is_zero_matrix) {
+ /* No keys are still pressed.
+ * Enable only the KDI interrupt for future key pressures.
+ * (clear the KDI status bit and his sync chain before) */
+ reg_val = readw(keypad->mmio_base + KPSR);
+ reg_val |= KBD_STAT_KPKD | KBD_STAT_KDSC;
+ writew(reg_val, keypad->mmio_base + KPSR);
+
+ reg_val = readw(keypad->mmio_base + KPSR);
+ reg_val |= KBD_STAT_KDIE;
+ reg_val &= ~KBD_STAT_KRIE;
+ writew(reg_val, keypad->mmio_base + KPSR);
+ } else {
+ /* Still there are keys pressed. Schedule a rescan for multiple
+ * key pressure detection and enable the KRI interrupt for fast
+ * reaction to an all key release event. */
+ mod_timer(&keypad->check_matrix_timer,
+ jiffies + msecs_to_jiffies(60));
+
+ reg_val = readw(keypad->mmio_base + KPSR);
+ reg_val |= KBD_STAT_KPKR | KBD_STAT_KRSS;
+ writew(reg_val, keypad->mmio_base + KPSR);
+
+ reg_val = readw(keypad->mmio_base + KPSR);
+ reg_val |= KBD_STAT_KRIE;
+ reg_val &= ~KBD_STAT_KDIE;
+ writew(reg_val, keypad->mmio_base + KPSR);
+ }
+}
+
+static irqreturn_t mxc_keypad_irq_handler(int irq, void *dev_id)
+{
+ struct mxc_keypad *keypad = dev_id;
+ unsigned short reg_val;
+
+ reg_val = readw(keypad->mmio_base + KPSR);
+
+ /* Disable every keypad interrupt */
+ reg_val &= ~(KBD_STAT_KRIE | KBD_STAT_KDIE);
+ /* Clear interrupts status bits */
+ reg_val |= KBD_STAT_KPKR | KBD_STAT_KPKD;
+ writew(reg_val, keypad->mmio_base + KPSR);
+
+ /* The matrix is supposed to be changed */
+ keypad->stable_count = 0;
+
+ /* Schedule the scanning procedure near in the future */
+ mod_timer(&keypad->check_matrix_timer, jiffies + msecs_to_jiffies(2));
+
+ return IRQ_HANDLED;
+}
+
+static void mxc_keypad_config(struct mxc_keypad *keypad)
+{
+ unsigned short reg_val;
+
+ /* Include enabled rows in interrupt generation (KPCR[7:0])
+ * Configure keypad columns as open-drain (KPCR[15:8]) */
+ reg_val = readw(keypad->mmio_base + KPCR);
+ reg_val |= keypad->rows_en_mask & 0xff; /* rows */
+ reg_val |= (keypad->cols_en_mask & 0xff) << 8; /* cols */
+ writew(reg_val, keypad->mmio_base + KPCR);
+
+ /* Write 0's to KPDR[15:8] (Colums)*/
+ reg_val = readw(keypad->mmio_base + KPDR);
+ reg_val &= 0x00ff;
+ writew(reg_val, keypad->mmio_base + KPDR);
+
+ /* Configure columns as output, rows as input (KDDR[15:0]) */
+ writew(0xff00, keypad->mmio_base + KDDR);
+
+ /* Clear Key Depress and Key Release status bit.
+ * Clear both synchronizer chain. */
+ reg_val = readw(keypad->mmio_base + KPSR);
+ reg_val |= KBD_STAT_KPKR | KBD_STAT_KPKD |
+ KBD_STAT_KDSC | KBD_STAT_KRSS;
+ writew(reg_val, keypad->mmio_base + KPSR);
+
+ /* Enable KDI and disable KRI (avoid false release events). */
+ reg_val |= KBD_STAT_KDIE;
+ reg_val &= ~KBD_STAT_KRIE;
+ writew(reg_val, keypad->mmio_base + KPSR);
+}
+
+static void mxc_keypad_inhibit(struct mxc_keypad *keypad)
+{
+ unsigned short reg_val;
+
+ /* Inhibit KDI and KRI interrupts. */
+ reg_val = readw(keypad->mmio_base + KPSR);
+ reg_val &= ~(KBD_STAT_KRIE | KBD_STAT_KDIE);
+ writew(reg_val, keypad->mmio_base + KPSR);
+
+ /* Colums as open drain and disable all rows */
+ writew(0xff00, keypad->mmio_base + KPCR);
+}
+
+static int mxc_keypad_open(struct input_dev *dev)
+{
+ struct mxc_keypad *keypad = input_get_drvdata(dev);
+
+ dev_dbg(&dev->dev, ">%s\n", __func__);
+
+ /* Init Keypad timer */
+ init_timer(&keypad->check_matrix_timer);
+ keypad->check_matrix_timer.function = mxc_keypad_check_for_events;
+ keypad->check_matrix_timer.data = (unsigned long) keypad;
+
+ /* Enable the kpp clock */
+ clk_enable(keypad->clk);
+ mxc_keypad_config(keypad);
+
+ /* Sanity control, not all the rows must be actived now. */
+ if ((readw(keypad->mmio_base + KPDR) & keypad->rows_en_mask) == 0) {
+ dev_err(&dev->dev,
+ "too much keys pressed for now, control pins initialisation\n");
+ goto open_err;
+ }
+
+ return 0;
+
+open_err:
+ keypad->exit_flag = true;
+ del_timer_sync(&keypad->check_matrix_timer);
+ mxc_keypad_inhibit(keypad);
+ return -EIO;
+}
+
+static void mxc_keypad_close(struct input_dev *dev)
+{
+ struct mxc_keypad *keypad = input_get_drvdata(dev);
+
+ dev_dbg(&dev->dev, ">%s\n", __func__);
+
+ /* Make sure no checks are pending and release any events.*/
+ keypad->exit_flag = true;
+ del_timer_sync(&keypad->check_matrix_timer);
+ mxc_keypad_check_for_events((unsigned long) keypad);
+
+ mxc_keypad_inhibit(keypad);
+
+ /* Disable clock unit */
+ clk_disable(keypad->clk);
+}
+
+static int __devinit mxc_keypad_probe(struct platform_device *pdev)
+{
+ const struct matrix_keymap_data *keymap_data = pdev->dev.platform_data;
+ struct mxc_keypad *keypad;
+ struct input_dev *input_dev;
+ struct resource *res;
+ int irq, error, i;
+
+ if (keymap_data == NULL) {
+ dev_err(&pdev->dev, "no keymap defined\n");
+ return -EINVAL;
+ }
+
+ irq = platform_get_irq(pdev, 0);
+ if (irq < 0) {
+ dev_err(&pdev->dev, "no irq defined in platform data\n");
+ return -EINVAL;
+ }
+
+ res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+ if (res == NULL) {
+ dev_err(&pdev->dev, "no I/O memory defined in platform data\n");
+ return -EINVAL;
+ }
+
+ res = request_mem_region(res->start, resource_size(res), pdev->name);
+ if (res == NULL) {
+ dev_err(&pdev->dev, "failed to request I/O memory\n");
+ return -EBUSY;
+ }
+
+ input_dev = input_allocate_device();
+ if (!input_dev) {
+ dev_err(&pdev->dev, "failed to allocate the input device\n");
+ error = -ENOMEM;
+ goto failed_rel_mem;
+ }
+
+ keypad = kzalloc(sizeof(struct mxc_keypad), GFP_KERNEL);
+ if (!keypad) {
+ dev_err(&pdev->dev, "not enough memory for driver data\n");
+ error = -ENOMEM;
+ goto failed_free_input;
+ }
+
+ keypad->input_dev = input_dev;
+ keypad->irq = irq;
+ keypad->stable_count = 0;
+ keypad->exit_flag = false;
+
+ keypad->mmio_base = ioremap(res->start, resource_size(res));
+ if (keypad->mmio_base == NULL) {
+ dev_err(&pdev->dev, "failed to remap I/O memory\n");
+ error = -ENOMEM;
+ goto failed_free_priv;
+ }
+
+ keypad->clk = clk_get(&pdev->dev, "kpp");
+ if (IS_ERR(keypad->clk)) {
+ dev_err(&pdev->dev, "failed to get keypad clock\n");
+ error = PTR_ERR(keypad->clk);
+ goto failed_unmap;
+ }
+
+ /* Search for rows and cols enabled */
+ for (i = 0; i < keymap_data->keymap_size; i++) {
+ keypad->rows_en_mask |= 1 << KEY_ROW(keymap_data->keymap[i]);
+ keypad->cols_en_mask |= 1 << KEY_COL(keymap_data->keymap[i]);
+ }
+
+ if (keypad->rows_en_mask > ((1 << MAX_MATRIX_KEY_ROWS) - 1) ||
+ keypad->cols_en_mask > ((1 << MAX_MATRIX_KEY_COLS) - 1)) {
+ dev_err(&pdev->dev, "invalid key data (too rows or colums)\n");
+ error = -EINVAL;
+ goto failed_clock_put;
+ }
+ dev_dbg(&pdev->dev, "enabled rows mask: %x\n", keypad->rows_en_mask);
+ dev_dbg(&pdev->dev, "enabled cols mask: %x\n", keypad->cols_en_mask);
+
+ /* Init the Input device */
+ input_dev->name = pdev->name;
+ input_dev->id.bustype = BUS_HOST;
+ input_dev->dev.parent = &pdev->dev;
+ input_dev->open = mxc_keypad_open;
+ input_dev->close = mxc_keypad_close;
+ input_dev->evbit[0] = BIT_MASK(EV_KEY) | BIT_MASK(EV_REP);
+ input_dev->keycode = keypad->keycodes;
+ input_dev->keycodesize = sizeof(keypad->keycodes[0]);
+ input_dev->keycodemax = ARRAY_SIZE(keypad->keycodes);
+
+ matrix_keypad_build_keymap(keymap_data, MATRIX_ROW_SHIFT,
+ keypad->keycodes, input_dev->keybit);
+
+ input_set_capability(input_dev, EV_MSC, MSC_SCAN);
+ input_set_drvdata(input_dev, keypad);
+
+ error = request_irq(irq, mxc_keypad_irq_handler, IRQF_DISABLED,
+ pdev->name, keypad);
+ if (error) {
+ dev_err(&pdev->dev, "failed to request IRQ\n");
+ goto failed_clock_put;
+ }
+
+ /* Register the input device */
+ error = input_register_device(input_dev);
+ if (error) {
+ dev_err(&pdev->dev, "failed to register input device\n");
+ goto failed_free_irq;
+ }
+
+ platform_set_drvdata(pdev, keypad);
+ device_init_wakeup(&pdev->dev, 1);
+
+ dev_info(&pdev->dev, "device probed\n");
+
+ return 0;
+
+failed_free_irq:
+ free_irq(irq, pdev);
+failed_clock_put:
+ clk_put(keypad->clk);
+failed_unmap:
+ iounmap(keypad->mmio_base);
+failed_free_priv:
+ kfree(keypad);
+failed_free_input:
+ input_free_device(input_dev);
+failed_rel_mem:
+ release_mem_region(res->start, resource_size(res));
+ return error;
+}
+
+static int __devexit mxc_keypad_remove(struct platform_device *pdev)
+{
+ struct mxc_keypad *keypad = platform_get_drvdata(pdev);
+ struct resource *res;
+
+ dev_dbg(&pdev->dev, ">%s\n", __func__);
+
+ platform_set_drvdata(pdev, NULL);
+
+ input_unregister_device(keypad->input_dev);
+
+ free_irq(keypad->irq, keypad);
+ clk_put(keypad->clk);
+
+ iounmap(keypad->mmio_base);
+ res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+ release_mem_region(res->start, resource_size(res));
+
+ kfree(keypad);
+
+ dev_info(&pdev->dev, "device removed\n");
+
+ return 0;
+}
+
+static struct platform_driver mxc_keypad_driver = {
+ .driver = {
+ .name = "mxc-keypad",
+ .owner = THIS_MODULE,
+ },
+ .probe = mxc_keypad_probe,
+ .remove = __devexit_p(mxc_keypad_remove),
+};
+
+static int __init mxc_keypad_init(void)
+{
+ return platform_driver_register(&mxc_keypad_driver);
+}
+
+static void __exit mxc_keypad_exit(void)
+{
+ platform_driver_unregister(&mxc_keypad_driver);
+}
+
+module_init(mxc_keypad_init);
+module_exit(mxc_keypad_exit);
+
+MODULE_AUTHOR("Alberto Panizzo <maramaopercheseimorto at gmail.com>");
+MODULE_DESCRIPTION("MXC Keypad Port Driver");
+MODULE_LICENSE("GPL v2");
+MODULE_ALIAS("platform:mxc-keypad");
--
1.6.3.3
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