diff mbox

MXC: input: add mxc-keypad driver to support the keypad interface present in the mxc application processors family.

Message ID 1262977099.2050.75.camel@climbing-alby
State New, archived
Headers show

Commit Message

Alberto Panizzo Jan. 8, 2010, 6:58 p.m. UTC
None
diff mbox

Patch

diff --git a/arch/arm/plat-mxc/include/mach/mxc_keypad.h b/arch/arm/plat-mxc/include/mach/mxc_keypad.h
new file mode 100644
index 0000000..1b05093
--- /dev/null
+++ b/arch/arm/plat-mxc/include/mach/mxc_keypad.h
@@ -0,0 +1,20 @@ 
+#ifndef __MACH_MXC_KEYPAD_H
+#define __MACH_MXC_KEYPAD_H
+
+#define MAX_MATRIX_KEY_ROWS	(8)
+#define MAX_MATRIX_KEY_COLS	(8)
+#define MATRIX_ROW_SHIFT	(3)
+
+struct mxc_keypad_platform_data {
+
+	/* code map for the matrix keys */
+	unsigned int	matrix_key_rows;
+	unsigned int	matrix_key_cols;
+	unsigned int	*matrix_key_map;
+	int		matrix_key_map_size;
+
+	/* key debounce interval */
+	unsigned int	debounce_ms;
+};
+
+#endif /* __MACH_MXC_KEYPAD_H */
diff --git a/drivers/input/keyboard/Kconfig b/drivers/input/keyboard/Kconfig
index ee98b1b..eff32fe 100644
--- a/drivers/input/keyboard/Kconfig
+++ b/drivers/input/keyboard/Kconfig
@@ -282,6 +282,15 @@  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 babad5e..9c7133a 100644
--- a/drivers/input/keyboard/Makefile
+++ b/drivers/input/keyboard/Makefile
@@ -23,6 +23,7 @@  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..4acd311
--- /dev/null
+++ b/drivers/input/keyboard/mxc_keypad.c
@@ -0,0 +1,485 @@ 
+/*
+ * linux/drivers/input/keyboard/mxc_keypad.c
+ *
+ * Driver for the MXC keypad port.
+ * Copyright (C) 2009 Alberto Panizzo <maramaopercheseimorto@gmail.com>
+ *  based on Rodolfo Giometti & others work in pxa27x_keypad.c
+ *
+ * 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.h>
+#include <linux/input/matrix_keypad.h>
+#include <linux/interrupt.h>
+#include <linux/io.h>
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/platform_device.h>
+
+#include <mach/mxc_keypad.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 */
+#define KBD_STAT_KPKR	(0x1 << 1) /* Key Release Interrupt Status bit */
+#define KBD_STAT_KDSC	(0x1 << 2) /* Key Depress Synch Chain Status bit */
+#define KBD_STAT_KRSS	(0x1 << 3) /* Key Release Synch Status bit */
+#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 keypad_readw(off)	__raw_readw(keypad->mmio_base + (off))
+#define keypad_writew(off, v)	__raw_writew((v), keypad->mmio_base + (off))
+
+#define MAX_MATRIX_KEY_NUM	(MAX_MATRIX_KEY_ROWS * MAX_MATRIX_KEY_COLS)
+
+struct mxc_keypad {
+	struct mxc_keypad_platform_data *pdata;
+
+	struct clk *clk;
+	struct input_dev *input_dev;
+	void __iomem *mmio_base;
+
+	int			irq;
+
+#define MXC_IRQ_DEPRESS		1
+#define MXC_IRQ_RELEASE		2
+	unsigned int		irq_type;
+
+	int 			irq_since_last_change;
+
+	unsigned short 		keycodes[MAX_MATRIX_KEY_NUM];
+
+	/* state row bits of each column scan */
+	unsigned short 		matrix_key_state[MAX_MATRIX_KEY_COLS];
+};
+
+static void mxc_keypad_build_keycode(struct mxc_keypad *keypad)
+{
+	struct mxc_keypad_platform_data *pdata = keypad->pdata;
+	struct input_dev *input_dev = keypad->input_dev;
+	unsigned short keycode;
+	int i;
+
+	for (i = 0; i < pdata->matrix_key_map_size; i++) {
+		unsigned int key = pdata->matrix_key_map[i];
+		unsigned int row = KEY_ROW(key);
+		unsigned int col = KEY_COL(key);
+		unsigned int scancode = MATRIX_SCAN_CODE(row, col,
+							 MATRIX_ROW_SHIFT);
+
+		keycode = KEY_VAL(key);
+		keypad->keycodes[scancode] = keycode;
+		__set_bit(keycode, input_dev->keybit);
+	}
+
+	__clear_bit(KEY_RESERVED, input_dev->keybit);
+}
+
+/* Return 0 if no changes are detected in matrix */
+static int mxc_keypad_scan_matrix(struct mxc_keypad *keypad)
+{
+	struct mxc_keypad_platform_data *pdata = keypad->pdata;
+	struct input_dev *input_dev = keypad->input_dev;
+	int row, col, changed = 0;
+	unsigned short new_state[MAX_MATRIX_KEY_COLS];
+	unsigned short reg_val;
+
+	memset(new_state, 0, sizeof(new_state));
+
+	for (col = 0; col < pdata->matrix_key_cols; col++) {
+		/* 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 = keypad_readw(KPDR);
+		reg_val |= 0xff00;
+		keypad_writew(KPDR, reg_val);
+
+		reg_val = keypad_readw(KPCR);
+		reg_val &= ~(((1 << pdata->matrix_key_cols) - 1) << 8);
+		keypad_writew(KPCR, reg_val);
+
+		udelay(2);
+
+		reg_val = keypad_readw(KPCR);
+		reg_val |= ((1 << pdata->matrix_key_cols) - 1) << 8;
+		keypad_writew(KPCR, reg_val);
+
+		/*
+		 * 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 = keypad_readw(KPDR);
+		reg_val &= ~(1 << (8 + col));
+		keypad_writew(KPDR, reg_val);
+
+		/* Delay added to avoid propagating the 0 from column to row
+		 * when scanning. */
+		udelay(5);
+
+		/* 1s in state detect a key pressure */
+		new_state[col] = (~keypad_readw(KPDR)) & 0x00ff;
+	}
+
+	/* Test the state changes */
+	for (col = 0; col < pdata->matrix_key_cols; col++) {
+		unsigned short bits_changed;
+		int code;
+
+		bits_changed = keypad->matrix_key_state[col] ^ new_state[col];
+		if (bits_changed == 0)
+			continue;
+
+		changed = 1;
+		for (row = 0; row < pdata->matrix_key_rows; row++) {
+			if ((bits_changed & (1 << row)) == 0)
+				continue;
+
+			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],
+					 new_state[col] & (1 << row));
+			dev_dbg(&input_dev->dev, "Event code: %d, val: %d",
+					keypad->keycodes[code],
+					new_state[col] & (1 << row));
+		}
+	}
+	input_sync(input_dev);
+	memcpy(keypad->matrix_key_state, new_state, sizeof(new_state));
+
+	/* Return in standby mode:
+	 * 9. write 0s to columns */
+	reg_val = keypad_readw(KPDR);
+	reg_val &= 0x00ff;
+	keypad_writew(KPDR, reg_val);
+
+	return changed;
+}
+
+static irqreturn_t mxc_keypad_irq_handler_thread(int irq, void *dev_id)
+{
+	struct mxc_keypad *keypad = dev_id;
+	struct mxc_keypad_platform_data *pdata = keypad->pdata;
+	struct input_dev *idev = keypad->input_dev;
+	unsigned short reg_val;
+
+	dev_dbg(&idev->dev, "Handling Interrupt of type %x\n",
+						keypad->irq_type);
+
+	/* Wait till debounce */
+	msleep(pdata->debounce_ms);
+
+	/* Do the scan routine and Keep track for how many time we got
+	 * interrupt that make no change */
+	if (mxc_keypad_scan_matrix(keypad))
+		keypad->irq_since_last_change = 0;
+	else
+		keypad->irq_since_last_change++;
+
+	/* If the key is pressed since too many time, relax the update period */
+	if (keypad->irq_since_last_change > 2)
+		msleep(100);
+
+	/* 10. Clear KPKD and KPKR status bits
+	 *     Set the KPKR sync chain and clear the KPKD sync chain */
+	reg_val = keypad_readw(KPSR);
+	reg_val |= KBD_STAT_KPKD | KBD_STAT_KPKR |
+		   KBD_STAT_KDSC | KBD_STAT_KRSS;
+	keypad_writew(KPSR, reg_val);
+
+	/* Re enable interrupts and clear sync reset bits.
+	 * Next KDI is used for detect multiple pressures. */
+	reg_val = keypad_readw(KPSR);
+	reg_val &= ~(KBD_STAT_KDSC | KBD_STAT_KRSS);
+	keypad_writew(KPSR, reg_val);
+
+	reg_val |= KBD_STAT_KDIE | KBD_STAT_KRIE;
+	if (keypad->irq_type == MXC_IRQ_RELEASE)
+		reg_val &= ~KBD_STAT_KRIE;
+	keypad_writew(KPSR, reg_val);
+
+	return IRQ_HANDLED;
+}
+static irqreturn_t mxc_keypad_irq_handler(int irq, void *dev_id)
+{
+	struct mxc_keypad *keypad = dev_id;
+	unsigned short reg_val;
+
+	/* Disable every interrupt */
+	reg_val = keypad_readw(KPSR);
+	reg_val &= ~(KBD_STAT_KRIE | KBD_STAT_KDIE);
+	keypad_writew(KPSR, reg_val);
+
+	keypad->irq_type = reg_val & KBD_STAT_KPKD ?
+			   MXC_IRQ_DEPRESS : MXC_IRQ_RELEASE;
+
+	return IRQ_WAKE_THREAD;
+}
+
+static void mxc_keypad_config(struct mxc_keypad *keypad)
+{
+	struct mxc_keypad_platform_data *pdata = keypad->pdata;
+	unsigned short reg_val;
+
+	/* Enable number of rows in keypad (KPCR[7:0])
+	 * Configure keypad columns as open-drain (KPCR[15:8])
+	 */
+	reg_val = keypad_readw(KPCR);
+	reg_val |= (1 << pdata->matrix_key_rows) - 1;		/* LSB */
+	reg_val |= ((1 << pdata->matrix_key_cols) - 1) << 8;	/* MSB */
+	keypad_writew(KPCR, reg_val);
+
+	/* Write 0's to KPDR[15:8] (Colums)*/
+	reg_val = keypad_readw(KPDR);
+	reg_val &= 0x00ff;
+	keypad_writew(KPDR, reg_val);
+
+	/* Configure columns as output, rows as input (KDDR[15:0]) */
+	reg_val = keypad_readw(KDDR);
+	reg_val |= 0xff00;
+	reg_val &= 0xff00;
+	keypad_writew(KDDR, reg_val);
+
+	/* Clear Key Depress and Key Release status bit.
+	 * Clear synchronizer chain.
+	 * */
+	reg_val = keypad_readw(KPSR);
+	reg_val |= KBD_STAT_KPKR | KBD_STAT_KPKD |
+		   KBD_STAT_KDSC | KBD_STAT_KRSS;
+	keypad_writew(KPSR, reg_val);
+
+	/* Set the KDIE control bit, and clear the KRIE control bit
+	 * (avoid false release events). */
+	reg_val |= KBD_STAT_KDIE;
+	reg_val &= ~KBD_STAT_KRIE;
+	keypad_writew(KPSR, reg_val);
+}
+
+static void mxc_keypad_inhibit(struct mxc_keypad *keypad)
+{
+	unsigned short reg_val;
+
+	/* Colums as open drain and disable rows */
+	keypad_writew(KPCR, 0xff00);
+
+	/* Clear the KPKD status flag and synchronizer chain.
+	 * Clear KDIE control bit and KRIE control bit.
+	 */
+	reg_val = keypad_readw(KPSR);
+	reg_val |= KBD_STAT_KPKD | KBD_STAT_KDSC;
+	reg_val &= ~(KBD_STAT_KRIE | KBD_STAT_KDIE);
+	keypad_writew(KPSR, reg_val);
+}
+
+static int mxc_keypad_open(struct input_dev *dev)
+{
+	struct mxc_keypad *keypad = input_get_drvdata(dev);
+	struct mxc_keypad_platform_data *pdata = keypad->pdata;
+
+	dev_dbg(&dev->dev, "%s\n", __func__);
+
+	/* Enable unit clock */
+	clk_enable(keypad->clk);
+	mxc_keypad_config(keypad);
+
+	/* Sanity control, not all the rows must be to 0s now. */
+	if ((keypad_readw(KPDR) & ((1 << pdata->matrix_key_rows) - 1)) == 0) {
+		dev_err(&dev->dev, "Too much keys pressed for now. "
+				"Control pins initialisation.\n");
+		goto open_err;
+	}
+
+	return 0;
+
+open_err:
+	mxc_keypad_inhibit(keypad);
+	return -EIO;
+}
+
+static void mxc_keypad_close(struct input_dev *dev)
+{
+	struct mxc_keypad *keypad = input_get_drvdata(dev);
+
+	mxc_keypad_inhibit(keypad);
+
+	/* Disable clock unit */
+	clk_disable(keypad->clk);
+}
+
+static int __devinit mxc_keypad_probe(struct platform_device *pdev)
+{
+	struct mxc_keypad_platform_data *pdata = pdev->dev.platform_data;
+	struct mxc_keypad *keypad;
+	struct input_dev *input_dev;
+	struct resource *res;
+	int irq, error;
+
+	if (pdata == NULL) {
+		dev_err(&pdev->dev, "no platform data defined\n");
+		return -EINVAL;
+	}
+
+	irq = platform_get_irq(pdev, 0);
+	if (irq < 0) {
+		dev_err(&pdev->dev, "failed to get keypad irq\n");
+		return -ENXIO;
+	}
+
+	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+	if (res == NULL) {
+		dev_err(&pdev->dev, "failed to get I/O memory\n");
+		return -ENXIO;
+	}
+
+	keypad = kzalloc(sizeof(struct mxc_keypad), GFP_KERNEL);
+	input_dev = input_allocate_device();
+	if (!keypad || !input_dev) {
+		dev_err(&pdev->dev, "failed to allocate memory\n");
+		error = -ENOMEM;
+		goto failed_free;
+	}
+
+	keypad->pdata = pdata;
+	keypad->input_dev = input_dev;
+	keypad->irq = irq;
+
+	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");
+		error = -EBUSY;
+		goto failed_free;
+	}
+
+	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 = -ENXIO;
+		goto failed_free_mem;
+	}
+
+	keypad->clk = clk_get(NULL, "kpp");
+	if (IS_ERR(keypad->clk)) {
+		dev_err(&pdev->dev, "failed to get keypad clock\n");
+		error = PTR_ERR(keypad->clk);
+		goto failed_free_io;
+	}
+
+	input_dev->name = pdev->name;
+	input_dev->id.bustype = BUS_HOST;
+	input_dev->open = mxc_keypad_open;
+	input_dev->close = mxc_keypad_close;
+	input_dev->dev.parent = &pdev->dev;
+
+	input_dev->keycode = keypad->keycodes;
+	input_dev->keycodesize = sizeof(keypad->keycodes[0]);
+	input_dev->keycodemax = ARRAY_SIZE(keypad->keycodes);
+
+	input_set_drvdata(input_dev, keypad);
+
+	input_dev->evbit[0] = BIT_MASK(EV_KEY) | BIT_MASK(EV_REP);
+	input_set_capability(input_dev, EV_MSC, MSC_SCAN);
+
+	mxc_keypad_build_keycode(keypad);
+
+	error = request_threaded_irq(irq, mxc_keypad_irq_handler,
+			mxc_keypad_irq_handler_thread, IRQF_DISABLED,
+			pdev->name, keypad);
+	if (error) {
+		dev_err(&pdev->dev, "failed to request IRQ\n");
+		goto failed_put_clk;
+	}
+
+	/* 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_put_clk:
+	clk_put(keypad->clk);
+failed_free_io:
+	iounmap(keypad->mmio_base);
+failed_free_mem:
+	release_mem_region(res->start, resource_size(res));
+failed_free:
+	input_free_device(input_dev);
+	kfree(keypad);
+	return error;
+}
+
+static int __devexit mxc_keypad_remove(struct platform_device *pdev)
+{
+	struct mxc_keypad *keypad = platform_get_drvdata(pdev);
+	struct resource *res;
+
+	free_irq(keypad->irq, keypad);
+	clk_put(keypad->clk);
+
+	input_unregister_device(keypad->input_dev);
+	input_free_device(keypad->input_dev);
+
+	iounmap(keypad->mmio_base);
+
+	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+	release_mem_region(res->start, resource_size(res));
+
+	platform_set_drvdata(pdev, NULL);
+	kfree(keypad);
+
+	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@gmail.com>");
+MODULE_DESCRIPTION("MXC Keypad Port Driver");
+MODULE_LICENSE("GPL v2");
+MODULE_ALIAS("platform:mxc-keypad");