Merge branch 'next' into for-linus

Prepare first set of updates for 3.11 merge window.

26 files changed, 944 insertions, 93 deletions

diff --git a/drivers/input/keyboard/Kconfig b/drivers/input/keyboard/Kconfig
index c62ca1b47a3..269d4c3658c 100644
--- a/drivers/input/keyboard/Kconfig
+++ b/drivers/input/keyboard/Kconfig
@@ -175,7 +175,7 @@ config KEYBOARD_EP93XX
 
 config KEYBOARD_GPIO
 	tristate "GPIO Buttons"
-	depends on GENERIC_GPIO
+	depends on GPIOLIB
 	help
 	  This driver implements support for buttons connected
 	  to GPIO pins of various CPUs (and some other chips).
@@ -190,7 +190,7 @@ config KEYBOARD_GPIO
 
 config KEYBOARD_GPIO_POLLED
 	tristate "Polled GPIO buttons"
-	depends on GENERIC_GPIO
+	depends on GPIOLIB
 	select INPUT_POLLDEV
 	help
 	  This driver implements support for buttons connected
@@ -241,7 +241,7 @@ config KEYBOARD_TCA8418
 
 config KEYBOARD_MATRIX
 	tristate "GPIO driven matrix keypad support"
-	depends on GENERIC_GPIO
+	depends on GPIOLIB
 	select INPUT_MATRIXKMAP
 	help
 	  Enable support for GPIO driven matrix keypad.
@@ -418,6 +418,16 @@ config KEYBOARD_NOMADIK
 	  To compile this driver as a module, choose M here: the
 	  module will be called nmk-ske-keypad.
 
+config KEYBOARD_NSPIRE
+	tristate "TI-NSPIRE built-in keyboard"
+	depends on ARCH_NSPIRE && OF
+	select INPUT_MATRIXKMAP
+	help
+	  Say Y here if you want to use the built-in keypad on TI-NSPIRE.
+
+	  To compile this driver as a module, choose M here: the
+	  module will be called nspire-keypad.
+
 config KEYBOARD_TEGRA
 	tristate "NVIDIA Tegra internal matrix keyboard controller support"
 	depends on ARCH_TEGRA && OF
@@ -442,6 +452,7 @@ config KEYBOARD_OPENCORES
 config KEYBOARD_PXA27x
 	tristate "PXA27x/PXA3xx keypad support"
 	depends on PXA27x || PXA3xx || ARCH_MMP
+	select INPUT_MATRIXKMAP
 	help
 	  Enable support for PXA27x/PXA3xx keypad controller.
 
@@ -629,4 +640,16 @@ config KEYBOARD_W90P910
 	  To compile this driver as a module, choose M here: the
 	  module will be called w90p910_keypad.
 
+config KEYBOARD_CROS_EC
+	tristate "ChromeOS EC keyboard"
+	select INPUT_MATRIXKMAP
+	depends on MFD_CROS_EC
+	help
+	  Say Y here to enable the matrix keyboard used by ChromeOS devices
+	  and implemented on the ChromeOS EC. You must enable one bus option
+	  (MFD_CROS_EC_I2C or MFD_CROS_EC_SPI) to use this.
+
+	  To compile this driver as a module, choose M here: the
+	  module will be called cros_ec_keyb.
+
 endif
diff --git a/drivers/input/keyboard/Makefile b/drivers/input/keyboard/Makefile
index 49b16453d00..a699b617230 100644
--- a/drivers/input/keyboard/Makefile
+++ b/drivers/input/keyboard/Makefile
@@ -11,6 +11,7 @@ obj-$(CONFIG_KEYBOARD_AMIGA)		+= amikbd.o
 obj-$(CONFIG_KEYBOARD_ATARI)		+= atakbd.o
 obj-$(CONFIG_KEYBOARD_ATKBD)		+= atkbd.o
 obj-$(CONFIG_KEYBOARD_BFIN)		+= bf54x-keys.o
+obj-$(CONFIG_KEYBOARD_CROS_EC)		+= cros_ec_keyb.o
 obj-$(CONFIG_KEYBOARD_DAVINCI)		+= davinci_keyscan.o
 obj-$(CONFIG_KEYBOARD_EP93XX)		+= ep93xx_keypad.o
 obj-$(CONFIG_KEYBOARD_GOLDFISH_EVENTS)	+= goldfish_events.o
@@ -35,6 +36,7 @@ obj-$(CONFIG_KEYBOARD_MCS)		+= mcs_touchkey.o
 obj-$(CONFIG_KEYBOARD_MPR121)		+= mpr121_touchkey.o
 obj-$(CONFIG_KEYBOARD_NEWTON)		+= newtonkbd.o
 obj-$(CONFIG_KEYBOARD_NOMADIK)		+= nomadik-ske-keypad.o
+obj-$(CONFIG_KEYBOARD_NSPIRE)		+= nspire-keypad.o
 obj-$(CONFIG_KEYBOARD_OMAP)		+= omap-keypad.o
 obj-$(CONFIG_KEYBOARD_OMAP4)		+= omap4-keypad.o
 obj-$(CONFIG_KEYBOARD_OPENCORES)	+= opencores-kbd.o
diff --git a/drivers/input/keyboard/amikbd.c b/drivers/input/keyboard/amikbd.c
index ba0b36f7dae..096d6067ae1 100644
--- a/drivers/input/keyboard/amikbd.c
+++ b/drivers/input/keyboard/amikbd.c
@@ -246,7 +246,6 @@ static int __exit amikbd_remove(struct platform_device *pdev)
 {
 	struct input_dev *dev = platform_get_drvdata(pdev);
 
-	platform_set_drvdata(pdev, NULL);
 	free_irq(IRQ_AMIGA_CIAA_SP, dev);
 	input_unregister_device(dev);
 	return 0;
diff --git a/drivers/input/keyboard/bf54x-keys.c b/drivers/input/keyboard/bf54x-keys.c
index 20b9fa91fb9..fc88fb48d70 100644
--- a/drivers/input/keyboard/bf54x-keys.c
+++ b/drivers/input/keyboard/bf54x-keys.c
@@ -326,7 +326,6 @@ out0:
 	kfree(bf54x_kpad->keycode);
 out:
 	kfree(bf54x_kpad);
-	platform_set_drvdata(pdev, NULL);
 
 	return error;
 }
@@ -346,7 +345,6 @@ static int bfin_kpad_remove(struct platform_device *pdev)
 
 	kfree(bf54x_kpad->keycode);
 	kfree(bf54x_kpad);
-	platform_set_drvdata(pdev, NULL);
 
 	return 0;
 }
diff --git a/drivers/input/keyboard/cros_ec_keyb.c b/drivers/input/keyboard/cros_ec_keyb.c
new file mode 100644
index 00000000000..49557f27bfa
--- /dev/null
+++ b/drivers/input/keyboard/cros_ec_keyb.c
@@ -0,0 +1,334 @@
+/*
+ * ChromeOS EC keyboard driver
+ *
+ * Copyright (C) 2012 Google, Inc
+ *
+ * This software is licensed under the terms of the GNU General Public
+ * License version 2, as published by the Free Software Foundation, and
+ * may be copied, distributed, and modified under those terms.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * This driver uses the Chrome OS EC byte-level message-based protocol for
+ * communicating the keyboard state (which keys are pressed) from a keyboard EC
+ * to the AP over some bus (such as i2c, lpc, spi).  The EC does debouncing,
+ * but everything else (including deghosting) is done here.  The main
+ * motivation for this is to keep the EC firmware as simple as possible, since
+ * it cannot be easily upgraded and EC flash/IRAM space is relatively
+ * expensive.
+ */
+
+#include <linux/module.h>
+#include <linux/i2c.h>
+#include <linux/input.h>
+#include <linux/kernel.h>
+#include <linux/notifier.h>
+#include <linux/platform_device.h>
+#include <linux/slab.h>
+#include <linux/input/matrix_keypad.h>
+#include <linux/mfd/cros_ec.h>
+#include <linux/mfd/cros_ec_commands.h>
+
+/*
+ * @rows: Number of rows in the keypad
+ * @cols: Number of columns in the keypad
+ * @row_shift: log2 or number of rows, rounded up
+ * @keymap_data: Matrix keymap data used to convert to keyscan values
+ * @ghost_filter: true to enable the matrix key-ghosting filter
+ * @dev: Device pointer
+ * @idev: Input device
+ * @ec: Top level ChromeOS device to use to talk to EC
+ * @event_notifier: interrupt event notifier for transport devices
+ */
+struct cros_ec_keyb {
+	unsigned int rows;
+	unsigned int cols;
+	int row_shift;
+	const struct matrix_keymap_data *keymap_data;
+	bool ghost_filter;
+
+	struct device *dev;
+	struct input_dev *idev;
+	struct cros_ec_device *ec;
+	struct notifier_block notifier;
+};
+
+
+static bool cros_ec_keyb_row_has_ghosting(struct cros_ec_keyb *ckdev,
+					  uint8_t *buf, int row)
+{
+	int pressed_in_row = 0;
+	int row_has_teeth = 0;
+	int col, mask;
+
+	mask = 1 << row;
+	for (col = 0; col < ckdev->cols; col++) {
+		if (buf[col] & mask) {
+			pressed_in_row++;
+			row_has_teeth |= buf[col] & ~mask;
+			if (pressed_in_row > 1 && row_has_teeth) {
+				/* ghosting */
+				dev_dbg(ckdev->dev,
+					"ghost found at: r%d c%d, pressed %d, teeth 0x%x\n",
+					row, col, pressed_in_row,
+					row_has_teeth);
+				return true;
+			}
+		}
+	}
+
+	return false;
+}
+
+/*
+ * Returns true when there is at least one combination of pressed keys that
+ * results in ghosting.
+ */
+static bool cros_ec_keyb_has_ghosting(struct cros_ec_keyb *ckdev, uint8_t *buf)
+{
+	int row;
+
+	/*
+	 * Ghosting happens if for any pressed key X there are other keys
+	 * pressed both in the same row and column of X as, for instance,
+	 * in the following diagram:
+	 *
+	 * . . Y . g .
+	 * . . . . . .
+	 * . . . . . .
+	 * . . X . Z .
+	 *
+	 * In this case only X, Y, and Z are pressed, but g appears to be
+	 * pressed too (see Wikipedia).
+	 *
+	 * We can detect ghosting in a single pass (*) over the keyboard state
+	 * by maintaining two arrays.  pressed_in_row counts how many pressed
+	 * keys we have found in a row.  row_has_teeth is true if any of the
+	 * pressed keys for this row has other pressed keys in its column.  If
+	 * at any point of the scan we find that a row has multiple pressed
+	 * keys, and at least one of them is at the intersection with a column
+	 * with multiple pressed keys, we're sure there is ghosting.
+	 * Conversely, if there is ghosting, we will detect such situation for
+	 * at least one key during the pass.
+	 *
+	 * (*) This looks linear in the number of keys, but it's not.  We can
+	 * cheat because the number of rows is small.
+	 */
+	for (row = 0; row < ckdev->rows; row++)
+		if (cros_ec_keyb_row_has_ghosting(ckdev, buf, row))
+			return true;
+
+	return false;
+}
+
+/*
+ * Compares the new keyboard state to the old one and produces key
+ * press/release events accordingly.  The keyboard state is 13 bytes (one byte
+ * per column)
+ */
+static void cros_ec_keyb_process(struct cros_ec_keyb *ckdev,
+			 uint8_t *kb_state, int len)
+{
+	struct input_dev *idev = ckdev->idev;
+	int col, row;
+	int new_state;
+	int num_cols;
+
+	num_cols = len;
+
+	if (ckdev->ghost_filter && cros_ec_keyb_has_ghosting(ckdev, kb_state)) {
+		/*
+		 * Simple-minded solution: ignore this state. The obvious
+		 * improvement is to only ignore changes to keys involved in
+		 * the ghosting, but process the other changes.
+		 */
+		dev_dbg(ckdev->dev, "ghosting found\n");
+		return;
+	}
+
+	for (col = 0; col < ckdev->cols; col++) {
+		for (row = 0; row < ckdev->rows; row++) {
+			int pos = MATRIX_SCAN_CODE(row, col, ckdev->row_shift);
+			const unsigned short *keycodes = idev->keycode;
+			int code;
+
+			code = keycodes[pos];
+			new_state = kb_state[col] & (1 << row);
+			if (!!new_state != test_bit(code, idev->key)) {
+				dev_dbg(ckdev->dev,
+					"changed: [r%d c%d]: byte %02x\n",
+					row, col, new_state);
+
+				input_report_key(idev, code, new_state);
+			}
+		}
+	}
+	input_sync(ckdev->idev);
+}
+
+static int cros_ec_keyb_open(struct input_dev *dev)
+{
+	struct cros_ec_keyb *ckdev = input_get_drvdata(dev);
+
+	return blocking_notifier_chain_register(&ckdev->ec->event_notifier,
+						&ckdev->notifier);
+}
+
+static void cros_ec_keyb_close(struct input_dev *dev)
+{
+	struct cros_ec_keyb *ckdev = input_get_drvdata(dev);
+
+	blocking_notifier_chain_unregister(&ckdev->ec->event_notifier,
+					   &ckdev->notifier);
+}
+
+static int cros_ec_keyb_get_state(struct cros_ec_keyb *ckdev, uint8_t *kb_state)
+{
+	return ckdev->ec->command_recv(ckdev->ec, EC_CMD_MKBP_STATE,
+					  kb_state, ckdev->cols);
+}
+
+static int cros_ec_keyb_work(struct notifier_block *nb,
+		     unsigned long state, void *_notify)
+{
+	int ret;
+	struct cros_ec_keyb *ckdev = container_of(nb, struct cros_ec_keyb,
+						    notifier);
+	uint8_t kb_state[ckdev->cols];
+
+	ret = cros_ec_keyb_get_state(ckdev, kb_state);
+	if (ret >= 0)
+		cros_ec_keyb_process(ckdev, kb_state, ret);
+
+	return NOTIFY_DONE;
+}
+
+/* Clear any keys in the buffer */
+static void cros_ec_keyb_clear_keyboard(struct cros_ec_keyb *ckdev)
+{
+	uint8_t old_state[ckdev->cols];
+	uint8_t new_state[ckdev->cols];
+	unsigned long duration;
+	int i, ret;
+
+	/*
+	 * Keep reading until we see that the scan state does not change.
+	 * That indicates that we are done.
+	 *
+	 * Assume that the EC keyscan buffer is at most 32 deep.
+	 */
+	duration = jiffies;
+	ret = cros_ec_keyb_get_state(ckdev, new_state);
+	for (i = 1; !ret && i < 32; i++) {
+		memcpy(old_state, new_state, sizeof(old_state));
+		ret = cros_ec_keyb_get_state(ckdev, new_state);
+		if (0 == memcmp(old_state, new_state, sizeof(old_state)))
+			break;
+	}
+	duration = jiffies - duration;
+	dev_info(ckdev->dev, "Discarded %d keyscan(s) in %dus\n", i,
+		jiffies_to_usecs(duration));
+}
+
+static int cros_ec_keyb_probe(struct platform_device *pdev)
+{
+	struct cros_ec_device *ec = dev_get_drvdata(pdev->dev.parent);
+	struct device *dev = ec->dev;
+	struct cros_ec_keyb *ckdev;
+	struct input_dev *idev;
+	struct device_node *np;
+	int err;
+
+	np = pdev->dev.of_node;
+	if (!np)
+		return -ENODEV;
+
+	ckdev = devm_kzalloc(&pdev->dev, sizeof(*ckdev), GFP_KERNEL);
+	if (!ckdev)
+		return -ENOMEM;
+	err = matrix_keypad_parse_of_params(&pdev->dev, &ckdev->rows,
+					    &ckdev->cols);
+	if (err)
+		return err;
+
+	idev = devm_input_allocate_device(&pdev->dev);
+	if (!idev)
+		return -ENOMEM;
+
+	ckdev->ec = ec;
+	ckdev->notifier.notifier_call = cros_ec_keyb_work;
+	ckdev->dev = dev;
+	dev_set_drvdata(&pdev->dev, ckdev);
+
+	idev->name = ec->ec_name;
+	idev->phys = ec->phys_name;
+	__set_bit(EV_REP, idev->evbit);
+
+	idev->id.bustype = BUS_VIRTUAL;
+	idev->id.version = 1;
+	idev->id.product = 0;
+	idev->dev.parent = &pdev->dev;
+	idev->open = cros_ec_keyb_open;
+	idev->close = cros_ec_keyb_close;
+
+	ckdev->ghost_filter = of_property_read_bool(np,
+					"google,needs-ghost-filter");
+
+	err = matrix_keypad_build_keymap(NULL, NULL, ckdev->rows, ckdev->cols,
+					 NULL, idev);
+	if (err) {
+		dev_err(dev, "cannot build key matrix\n");
+		return err;
+	}
+
+	ckdev->row_shift = get_count_order(ckdev->cols);
+
+	input_set_capability(idev, EV_MSC, MSC_SCAN);
+	input_set_drvdata(idev, ckdev);
+	ckdev->idev = idev;
+	err = input_register_device(ckdev->idev);
+	if (err) {
+		dev_err(dev, "cannot register input device\n");
+		return err;
+	}
+
+	return 0;
+}
+
+#ifdef CONFIG_PM_SLEEP
+static int cros_ec_keyb_resume(struct device *dev)
+{
+	struct cros_ec_keyb *ckdev = dev_get_drvdata(dev);
+
+	/*
+	 * When the EC is not a wake source, then it could not have caused the
+	 * resume, so we clear the EC's key scan buffer. If the EC was a
+	 * wake source (e.g. the lid is open and the user might press a key to
+	 * wake) then the key scan buffer should be preserved.
+	 */
+	if (ckdev->ec->was_wake_device)
+		cros_ec_keyb_clear_keyboard(ckdev);
+
+	return 0;
+}
+
+#endif
+
+static SIMPLE_DEV_PM_OPS(cros_ec_keyb_pm_ops, NULL, cros_ec_keyb_resume);
+
+static struct platform_driver cros_ec_keyb_driver = {
+	.probe = cros_ec_keyb_probe,
+	.driver = {
+		.name = "cros-ec-keyb",
+		.pm	= &cros_ec_keyb_pm_ops,
+	},
+};
+
+module_platform_driver(cros_ec_keyb_driver);
+
+MODULE_LICENSE("GPL");
+MODULE_DESCRIPTION("ChromeOS EC keyboard driver");
+MODULE_ALIAS("platform:cros-ec-keyb");
diff --git a/drivers/input/keyboard/davinci_keyscan.c b/drivers/input/keyboard/davinci_keyscan.c
index 829753702b6..d15977a8361 100644
--- a/drivers/input/keyboard/davinci_keyscan.c
+++ b/drivers/input/keyboard/davinci_keyscan.c
@@ -314,8 +314,6 @@ static int davinci_ks_remove(struct platform_device *pdev)
 	iounmap(davinci_ks->base);
 	release_mem_region(davinci_ks->pbase, davinci_ks->base_size);
 
-	platform_set_drvdata(pdev, NULL);
-
 	kfree(davinci_ks);
 
 	return 0;
diff --git a/drivers/input/keyboard/ep93xx_keypad.c b/drivers/input/keyboard/ep93xx_keypad.c
index 9857e8fd098..47206bdba41 100644
--- a/drivers/input/keyboard/ep93xx_keypad.c
+++ b/drivers/input/keyboard/ep93xx_keypad.c
@@ -329,8 +329,7 @@ static int ep93xx_keypad_probe(struct platform_device *pdev)
 	return 0;
 
 failed_free_irq:
-	free_irq(keypad->irq, pdev);
-	platform_set_drvdata(pdev, NULL);
+	free_irq(keypad->irq, keypad);
 failed_free_dev:
 	input_free_device(input_dev);
 failed_put_clk:
@@ -351,9 +350,7 @@ static int ep93xx_keypad_remove(struct platform_device *pdev)
 	struct ep93xx_keypad *keypad = platform_get_drvdata(pdev);
 	struct resource *res;
 
-	free_irq(keypad->irq, pdev);
-
-	platform_set_drvdata(pdev, NULL);
+	free_irq(keypad->irq, keypad);
 
 	if (keypad->enabled)
 		clk_disable(keypad->clk);
diff --git a/drivers/input/keyboard/gpio_keys.c b/drivers/input/keyboard/gpio_keys.c
index b29ca651a39..440ce32462b 100644
--- a/drivers/input/keyboard/gpio_keys.c
+++ b/drivers/input/keyboard/gpio_keys.c
@@ -767,7 +767,6 @@ static int gpio_keys_probe(struct platform_device *pdev)
 	while (--i >= 0)
 		gpio_remove_key(&ddata->data[i]);
 
-	platform_set_drvdata(pdev, NULL);
  fail1:
 	input_free_device(input);
 	kfree(ddata);
diff --git a/drivers/input/keyboard/gpio_keys_polled.c b/drivers/input/keyboard/gpio_keys_polled.c
index 21147164874..cd5ed9e2216 100644
--- a/drivers/input/keyboard/gpio_keys_polled.c
+++ b/drivers/input/keyboard/gpio_keys_polled.c
@@ -324,7 +324,6 @@ err_free_gpio:
 
 err_free_bdev:
 	kfree(bdev);
-	platform_set_drvdata(pdev, NULL);
 
 err_free_pdata:
 	/* If we have no platform_data, we allocated pdata dynamically.  */
@@ -355,7 +354,6 @@ static int gpio_keys_polled_remove(struct platform_device *pdev)
 		kfree(pdata);
 
 	kfree(bdev);
-	platform_set_drvdata(pdev, NULL);
 
 	return 0;
 }
diff --git a/drivers/input/keyboard/jornada680_kbd.c b/drivers/input/keyboard/jornada680_kbd.c
index 74e75a6e8de..a2a034c25f0 100644
--- a/drivers/input/keyboard/jornada680_kbd.c
+++ b/drivers/input/keyboard/jornada680_kbd.c
@@ -233,7 +233,6 @@ static int jornada680kbd_probe(struct platform_device *pdev)
  failed:
 	printk(KERN_ERR "Jornadakbd: failed to register driver, error: %d\n",
 		error);
-	platform_set_drvdata(pdev, NULL);
 	input_free_polled_device(poll_dev);
 	kfree(jornadakbd);
 	return error;
@@ -244,7 +243,6 @@ static int jornada680kbd_remove(struct platform_device *pdev)
 {
 	struct jornadakbd *jornadakbd = platform_get_drvdata(pdev);
 
-	platform_set_drvdata(pdev, NULL);
 	input_unregister_polled_device(jornadakbd->poll_dev);
 	input_free_polled_device(jornadakbd->poll_dev);
 	kfree(jornadakbd);
diff --git a/drivers/input/keyboard/jornada720_kbd.c b/drivers/input/keyboard/jornada720_kbd.c
index 5ceef636df2..b0ad457ca9d 100644
--- a/drivers/input/keyboard/jornada720_kbd.c
+++ b/drivers/input/keyboard/jornada720_kbd.c
@@ -146,7 +146,6 @@ static int jornada720_kbd_probe(struct platform_device *pdev)
  fail2:	/* IRQ, DEVICE, MEMORY */
 	free_irq(IRQ_GPIO0, pdev);
  fail1:	/* DEVICE, MEMORY */
-	platform_set_drvdata(pdev, NULL);
 	input_free_device(input_dev);
 	kfree(jornadakbd);
 	return err;
@@ -157,7 +156,6 @@ static int jornada720_kbd_remove(struct platform_device *pdev)
 	struct jornadakbd *jornadakbd = platform_get_drvdata(pdev);
 
 	free_irq(IRQ_GPIO0, pdev);
-	platform_set_drvdata(pdev, NULL);
 	input_unregister_device(jornadakbd->input);
 	kfree(jornadakbd);
 
diff --git a/drivers/input/keyboard/lpc32xx-keys.c b/drivers/input/keyboard/lpc32xx-keys.c
index 1b8add6cfb9..42181435fe6 100644
--- a/drivers/input/keyboard/lpc32xx-keys.c
+++ b/drivers/input/keyboard/lpc32xx-keys.c
@@ -144,12 +144,13 @@ static int lpc32xx_parse_dt(struct device *dev,
 {
 	struct device_node *np = dev->of_node;
 	u32 rows = 0, columns = 0;
+	int err;
 
-	of_property_read_u32(np, "keypad,num-rows", &rows);
-	of_property_read_u32(np, "keypad,num-columns", &columns);
-	if (!rows || rows != columns) {
-		dev_err(dev,
-			"rows and columns must be specified and be equal!\n");
+	err = matrix_keypad_parse_of_params(dev, &rows, &columns);
+	if (err)
+		return err;
+	if (rows != columns) {
+		dev_err(dev, "rows and columns must be equal!\n");
 		return -EINVAL;
 	}
 
diff --git a/drivers/input/keyboard/matrix_keypad.c b/drivers/input/keyboard/matrix_keypad.c
index 71d77192ac1..90ff73ace42 100644
--- a/drivers/input/keyboard/matrix_keypad.c
+++ b/drivers/input/keyboard/matrix_keypad.c
@@ -549,8 +549,6 @@ static int matrix_keypad_remove(struct platform_device *pdev)
 	input_unregister_device(keypad->input_dev);
 	kfree(keypad);
 
-	platform_set_drvdata(pdev, NULL);
-
 	return 0;
 }
 
diff --git a/drivers/input/keyboard/nspire-keypad.c b/drivers/input/keyboard/nspire-keypad.c
new file mode 100644
index 00000000000..e0a1339e40e
--- /dev/null
+++ b/drivers/input/keyboard/nspire-keypad.c
@@ -0,0 +1,283 @@
+/*
+ *  Copyright (C) 2013 Daniel Tang <tangrs@tangrs.id.au>
+ *
+ * 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.
+ */
+
+#include <linux/input/matrix_keypad.h>
+#include <linux/platform_device.h>
+#include <linux/interrupt.h>
+#include <linux/io.h>
+#include <linux/delay.h>
+#include <linux/input.h>
+#include <linux/slab.h>
+#include <linux/clk.h>
+#include <linux/module.h>
+#include <linux/of.h>
+
+#define KEYPAD_SCAN_MODE	0x00
+#define KEYPAD_CNTL		0x04
+#define KEYPAD_INT		0x08
+#define KEYPAD_INTMSK		0x0C
+
+#define KEYPAD_DATA		0x10
+#define KEYPAD_GPIO		0x30
+
+#define KEYPAD_UNKNOWN_INT	0x40
+#define KEYPAD_UNKNOWN_INT_STS	0x44
+
+#define KEYPAD_BITMASK_COLS	11
+#define KEYPAD_BITMASK_ROWS	8
+
+struct nspire_keypad {
+	void __iomem *reg_base;
+	u32 int_mask;
+
+	struct input_dev *input;
+	struct clk *clk;
+
+	struct matrix_keymap_data *keymap;
+	int row_shift;
+
+	/* Maximum delay estimated assuming 33MHz APB */
+	u32 scan_interval;	/* In microseconds (~2000us max) */
+	u32 row_delay;		/* In microseconds (~500us max) */
+
+	u16 state[KEYPAD_BITMASK_ROWS];
+
+	bool active_low;
+};
+
+static irqreturn_t nspire_keypad_irq(int irq, void *dev_id)
+{
+	struct nspire_keypad *keypad = dev_id;
+	struct input_dev *input = keypad->input;
+	unsigned short *keymap = input->keycode;
+	unsigned int code;
+	int row, col;
+	u32 int_sts;
+	u16 state[8];
+	u16 bits, changed;
+
+	int_sts = readl(keypad->reg_base + KEYPAD_INT) & keypad->int_mask;
+	if (!int_sts)
+		return IRQ_NONE;
+
+	memcpy_fromio(state, keypad->reg_base + KEYPAD_DATA, sizeof(state));
+
+	for (row = 0; row < KEYPAD_BITMASK_ROWS; row++) {
+		bits = state[row];
+		if (keypad->active_low)
+			bits = ~bits;
+
+		changed = bits ^ keypad->state[row];
+		if (!changed)
+			continue;
+
+		keypad->state[row] = bits;
+
+		for (col = 0; col < KEYPAD_BITMASK_COLS; col++) {
+			if (!(changed & (1U << col)))
+				continue;
+
+			code = MATRIX_SCAN_CODE(row, col, keypad->row_shift);
+			input_event(input, EV_MSC, MSC_SCAN, code);
+			input_report_key(input, keymap[code],
+					 bits & (1U << col));
+		}
+	}
+
+	input_sync(input);
+
+	writel(0x3, keypad->reg_base + KEYPAD_INT);
+
+	return IRQ_HANDLED;
+}
+
+static int nspire_keypad_chip_init(struct nspire_keypad *keypad)
+{
+	unsigned long val = 0, cycles_per_us, delay_cycles, row_delay_cycles;
+
+	cycles_per_us = (clk_get_rate(keypad->clk) / 1000000);
+	if (cycles_per_us == 0)
+		cycles_per_us = 1;
+
+	delay_cycles = cycles_per_us * keypad->scan_interval;
+	WARN_ON(delay_cycles >= (1 << 16)); /* Overflow */
+	delay_cycles &= 0xffff;
+
+	row_delay_cycles = cycles_per_us * keypad->row_delay;
+	WARN_ON(row_delay_cycles >= (1 << 14)); /* Overflow */
+	row_delay_cycles &= 0x3fff;
+
+	val |= 3 << 0; /* Set scan mode to 3 (continuous scan) */
+	val |= row_delay_cycles << 2; /* Delay between scanning each row */
+	val |= delay_cycles << 16; /* Delay between scans */
+	writel(val, keypad->reg_base + KEYPAD_SCAN_MODE);
+
+	val = (KEYPAD_BITMASK_ROWS & 0xff) | (KEYPAD_BITMASK_COLS & 0xff)<<8;
+	writel(val, keypad->reg_base + KEYPAD_CNTL);
+
+	/* Enable interrupts */
+	keypad->int_mask = 1 << 1;
+	writel(keypad->int_mask, keypad->reg_base + 0xc);
+
+	/* Disable GPIO interrupts to prevent hanging on touchpad */
+	/* Possibly used to detect touchpad events */
+	writel(0, keypad->reg_base + KEYPAD_UNKNOWN_INT);
+	/* Acknowledge existing interrupts */
+	writel(~0, keypad->reg_base + KEYPAD_UNKNOWN_INT_STS);
+
+	return 0;
+}
+
+static int nspire_keypad_open(struct input_dev *input)
+{
+	struct nspire_keypad *keypad = input_get_drvdata(input);
+	int error;
+
+	error = clk_prepare_enable(keypad->clk);
+	if (error)
+		return error;
+
+	error = nspire_keypad_chip_init(keypad);
+	if (error)
+		return error;
+
+	return 0;
+}
+
+static void nspire_keypad_close(struct input_dev *input)
+{
+	struct nspire_keypad *keypad = input_get_drvdata(input);
+
+	clk_disable_unprepare(keypad->clk);
+}
+
+static int nspire_keypad_probe(struct platform_device *pdev)
+{
+	const struct device_node *of_node = pdev->dev.of_node;
+	struct nspire_keypad *keypad;
+	struct input_dev *input;
+	struct resource *res;
+	int irq;
+	int error;
+
+	irq = platform_get_irq(pdev, 0);
+	if (irq < 0) {
+		dev_err(&pdev->dev, "failed to get keypad irq\n");
+		return -EINVAL;
+	}
+
+	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+	if (!res) {
+		dev_err(&pdev->dev, "missing platform resources\n");
+		return -EINVAL;
+	}
+
+	keypad = devm_kzalloc(&pdev->dev, sizeof(struct nspire_keypad),
+			      GFP_KERNEL);
+	if (!keypad) {
+		dev_err(&pdev->dev, "failed to allocate keypad memory\n");
+		return -ENOMEM;
+	}
+
+	keypad->row_shift = get_count_order(KEYPAD_BITMASK_COLS);
+
+	error = of_property_read_u32(of_node, "scan-interval",
+				     &keypad->scan_interval);
+	if (error) {
+		dev_err(&pdev->dev, "failed to get scan-interval\n");
+		return error;
+	}
+
+	error = of_property_read_u32(of_node, "row-delay",
+				     &keypad->row_delay);
+	if (error) {
+		dev_err(&pdev->dev, "failed to get row-delay\n");
+		return error;
+	}
+
+	keypad->active_low = of_property_read_bool(of_node, "active-low");
+
+	keypad->clk = devm_clk_get(&pdev->dev, NULL);
+	if (IS_ERR(keypad->clk)) {
+		dev_err(&pdev->dev, "unable to get clock\n");
+		return PTR_ERR(keypad->clk);
+	}
+
+	keypad->reg_base = devm_ioremap_resource(&pdev->dev, res);
+	if (IS_ERR(keypad->reg_base))
+		return PTR_ERR(keypad->reg_base);
+
+	keypad->input = input = devm_input_allocate_device(&pdev->dev);
+	if (!input) {
+		dev_err(&pdev->dev, "failed to allocate input device\n");
+		return -ENOMEM;
+	}
+
+	input_set_drvdata(input, keypad);
+
+	input->id.bustype = BUS_HOST;
+	input->name = "nspire-keypad";
+	input->open = nspire_keypad_open;
+	input->close = nspire_keypad_close;
+
+	__set_bit(EV_KEY, input->evbit);