diff mbox

TWL4030:TWL5030:TPS659x0: add keypad support

Message ID 1247876000-4457-1-git-send-email-vikram.pandita@ti.com (mailing list archive)
State Awaiting Upstream, archived
Headers show

Commit Message

vikram pandita July 18, 2009, 12:13 a.m. UTC 
The patch adds keypad support for TI TWL4030/TWL5030/TPS659x0
family of power chips

Signed-off-by: Vikram Pandita <vikram.pandita@ti.com>
---
 drivers/input/keyboard/Kconfig          |   11 
 drivers/input/keyboard/Makefile         |    1 
 drivers/input/keyboard/twl4030_keypad.c |  492 ++++++++++++++++++++++++++++++++
 3 files changed, 504 insertions(+)
 create mode 100644 drivers/input/keyboard/twl4030_keypad.c

--
To unsubscribe from this list: send the line "unsubscribe linux-omap" in
the body of a message to majordomo@vger.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html

Comments

Trilok Soni July 20, 2009, 7:06 a.m. UTC | #1 
Hi Vikram,

> +
> +#include <linux/kernel.h>
> +#include <linux/module.h>
> +#include <linux/init.h>
> +#include <linux/interrupt.h>
> +#include <linux/input.h>
> +#include <linux/platform_device.h>
> +#include <linux/i2c/twl4030.h>
> +#include <mach/keypad.h>

One empty line between above two headers.

I hope you are aware of earlier comments posted for this driver when
it was submitted few months back and had long discussion on threaded
irq stuff.

> +
> +/*
> + * 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 MAX_ROWS               8       /* TWL4030 hard limit */
> +
> +struct twl4030_keypad {
> +       unsigned        *keymap;
> +       unsigned int    keymapsize;
> +       u16             kp_state[MAX_ROWS];
> +       unsigned        n_rows;
> +       unsigned        n_cols;
> +       unsigned        irq;
> +
> +       struct device   *dbg_dev;
> +       struct input_dev *input;
> +};
> +
> +#define ROWCOL_MASK    KEY(0xf, 0xf, 0)
> +
> +/*----------------------------------------------------------------------*/
> +
> +/* 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_find_key(struct twl4030_keypad *kp, int col, int row)
> +{
> +       int i, rc;
> +
> +       rc = KEY(col, row, 0);
> +       for (i = 0; i < kp->keymapsize; i++)
> +               if ((kp->keymap[i] & ROWCOL_MASK) == rc)
> +                       return kp->keymap[i] & (KEYNUM_MASK | KEY_PERSISTENT);

This is an overhead. You should follow model like matrix_keypad.c
Please check latest -rc for matrix keypad driver. Also check Dmitry's
comment on KEY_PERSISTENT and how to remove them on earlier e-mail
thread discussion of this driver.

> +
> +       return -EINVAL;
> +}
> +
> +static inline u16 twl4030_col_xlate(struct twl4030_keypad *kp, u8 col)
> +{
> +       /* If all bits in a row are active for all coloumns then
> +        * we have that row line connected to gnd. Mark this
> +        * key on as if it was on matrix position n_cols (ie
> +        * 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[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 int 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 1;
> +               check |= col;
> +       }
> +
> +       return 0;
> +}
> +
> +static void twl4030_kp_scan(struct twl4030_keypad *kp, int release_all)
> +{
> +       u16 new_state[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;
> +
> +               for (col = 0; col < kp->n_cols; col++) {
> +                       int key;
> +
> +                       if (!(changed & (1 << col)))
> +                               continue;
> +
> +                       dev_dbg(kp->dbg_dev, "key [%d:%d] %s\n", row, col,
> +                               (new_state[row] & (1 << col)) ?
> +                               "press" : "release");
> +
> +                       key = twl4030_find_key(kp, col, row);
> +                       if (key < 0)
> +                               dev_warn(kp->dbg_dev,
> +                                       "Spurious key event %d-%d\n",
> +                                        col, row);
> +                       else if (key & KEY_PERSISTENT)
> +                               continue;
> +                       else
> +                               input_report_key(kp->input, key,
> +                                                new_state[row] & (1 << col));
> +               }
> +               kp->kp_state[row] = new_state[row];
> +       }
> +       input_sync(kp->input);
> +}
> +
> +/*
> + * Keypad interrupt handler
> + */
> +static irqreturn_t do_kp_irq(int irq, void *_kp)
> +{
> +       struct twl4030_keypad *kp = _kp;
> +       u8 reg;
> +       int ret;
> +
> +#ifdef CONFIG_LOCKDEP
> +       /* WORKAROUND for lockdep forcing IRQF_DISABLED on us, which
> +        * we don't want and can't tolerate.  Although it might be
> +        * friendlier not to borrow this thread context...
> +        */
> +       local_irq_enable();
> +#endif


This should go away after request_threaded_irq integration in
mainline, isn't it?

> +
> +       /* 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, 0);
> +       else
> +               twl4030_kp_scan(kp, 1);
> +
> +       return IRQ_HANDLED;
> +}
> +
> +/*
> + * Registers keypad device with input subsystem
> + * and configures TWL4030 keypad registers
> + */
> +static int __devinit twl4030_kp_probe(struct platform_device *pdev)
> +{
> +       u8 reg;
> +       int i;
> +       int ret = 0;
> +       struct twl4030_keypad *kp;
> +       struct twl4030_keypad_data *pdata = pdev->dev.platform_data;
> +
> +       if (!pdata || !pdata->rows || !pdata->cols || !pdata->keymap
> +                       || pdata->rows > 8 || pdata->cols > 8) {
> +               dev_err(&pdev->dev, "Invalid platform_data\n");
> +               return -EINVAL;
> +       }
> +
> +       kp = kzalloc(sizeof(*kp), GFP_KERNEL);
> +       if (!kp)
> +               return -ENOMEM;
> +
> +       platform_set_drvdata(pdev, kp);
> +
> +       /* Get the debug Device */
> +       kp->dbg_dev = &pdev->dev;
> +
> +       kp->input = input_allocate_device();
> +       if (!kp->input) {
> +               kfree(kp);
> +               return -ENOMEM;
> +       }
> +
> +       kp->keymap = pdata->keymap;
> +       kp->keymapsize = pdata->keymapsize;
> +       kp->n_rows = pdata->rows;
> +       kp->n_cols = pdata->cols;
> +       kp->irq = platform_get_irq(pdev, 0);
> +
> +       /* setup input device */
> +       __set_bit(EV_KEY, kp->input->evbit);
> +
> +       /* Enable auto repeat feature of Linux input subsystem */
> +       if (pdata->rep)
> +               __set_bit(EV_REP, kp->input->evbit);
> +
> +       for (i = 0; i < kp->keymapsize; i++)
> +               __set_bit(kp->keymap[i] & KEYNUM_MASK,
> +                               kp->input->keybit);
> +
> +       kp->input->name         = "TWL4030 Keypad";
> +       kp->input->phys         = "twl4030_keypad/input0";
> +       kp->input->dev.parent   = &pdev->dev;
> +
> +       kp->input->id.bustype   = BUS_HOST;
> +       kp->input->id.vendor    = 0x0001;
> +       kp->input->id.product   = 0x0001;
> +       kp->input->id.version   = 0x0003;
> +
> +       kp->input->keycode      = kp->keymap;
> +       kp->input->keycodesize  = sizeof(unsigned int);
> +       kp->input->keycodemax   = kp->keymapsize;
> +
> +       ret = input_register_device(kp->input);
> +       if (ret < 0) {
> +               dev_err(kp->dbg_dev,
> +                       "Unable to register twl4030 keypad device\n");
> +               goto err2;
> +       }
> +
> +       /* Enable controller, with hardware decoding but not autorepeat */
> +       reg = KEYP_CTRL_SOFT_NRST | KEYP_CTRL_SOFTMODEN
> +               | KEYP_CTRL_TOE_EN | KEYP_CTRL_KBD_ON;
> +       ret = twl4030_kpwrite_u8(kp, reg, KEYP_CTRL);
> +       if (ret < 0)
> +               goto err3;
> +
> +       /* 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;
> +       ret = twl4030_kpwrite_u8(kp, reg, KEYP_EDR);
> +       if (ret < 0)
> +               goto err3;
> +
> +       /* Set PTV prescaler Field */
> +       reg = (PTV_PRESCALER << KEYP_LK_PTV_PTV_SHIFT);
> +       ret = twl4030_kpwrite_u8(kp, reg, KEYP_LK_PTV);
> +       if (ret < 0)
> +               goto err3;
> +
> +       /* Set key debounce time to 20 ms */
> +       i = KEYP_PERIOD_US(20000, PTV_PRESCALER);

This should be flexible to be set by platform data and not hardcoded.

> +       ret = twl4030_kpwrite_u8(kp, i, KEYP_DEB);
> +       if (ret < 0)
> +               goto err3;
> +
> +       /* Set timeout period to 100 ms */
> +       i = KEYP_PERIOD_US(200000, PTV_PRESCALER);
> +       ret = twl4030_kpwrite_u8(kp, (i & 0xFF), KEYP_TIMEOUT_L);
> +       if (ret < 0)
> +               goto err3;

Ditto.

> +       ret = twl4030_kpwrite_u8(kp, (i >> 8), KEYP_TIMEOUT_H);
> +       if (ret < 0)
> +               goto err3;
> +
> +       /* 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;
> +       ret = twl4030_kpwrite_u8(kp, reg, KEYP_SIH_CTRL);
> +       if (ret < 0)
> +               goto err3;
> +
> +       /* initialize key state; irqs update it from here on */
> +       ret = twl4030_read_kp_matrix_state(kp, kp->kp_state);
> +       if (ret < 0)
> +               goto err3;
> +
> +       /*
> +        * 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 ...
> +        */
> +       ret = request_irq(kp->irq, do_kp_irq, 0, pdev->name, kp);
> +       if (ret < 0) {
> +               dev_info(kp->dbg_dev, "request_irq failed for irq no=%d\n",
> +                       kp->irq);
> +               goto err3;
> +       } else {
> +               /* Enable KP and TO interrupts now. */
> +               reg = (u8) ~(KEYP_IMR1_KP | KEYP_IMR1_TO);
> +               ret = twl4030_kpwrite_u8(kp, reg, KEYP_IMR1);
> +               if (ret < 0)
> +                       goto err5;
> +       }
> +
> +       return ret;
> +err5:
> +       /* mask all events - we don't care about the result */
> +       (void) twl4030_kpwrite_u8(kp, 0xff, KEYP_IMR1);
> +       free_irq(kp->irq, NULL);
> +err3:
> +       input_unregister_device(kp->input);
> +       kp->input = NULL;
> +err2:
> +       input_free_device(kp->input);
> +       kfree(kp);
> +       return -ENODEV;
> +}
> +
Amit Kucheria July 22, 2009, 2:25 p.m. UTC | #2 
On 09 Jul 20, Trilok Soni wrote:
> Hi Vikram,
> 
> > +
> > +#include <linux/kernel.h>
> > +#include <linux/module.h>
> > +#include <linux/init.h>
> > +#include <linux/interrupt.h>
> > +#include <linux/input.h>
> > +#include <linux/platform_device.h>
> > +#include <linux/i2c/twl4030.h>
> > +#include <mach/keypad.h>
> 
> One empty line between above two headers.
> 
> I hope you are aware of earlier comments posted for this driver when
> it was submitted few months back and had long discussion on threaded
> irq stuff.
>

Trilok,

Could you please post a link to that discussion. Google isn't pointing
me to any relevant discussions besides
http://lkml.org/lkml/2008/10/1/334

I'll do a further cleanup and resubmit.

Regards,
Amit
--
To unsubscribe from this list: send the line "unsubscribe linux-omap" in
the body of a message to majordomo@vger.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Trilok Soni July 22, 2009, 6:43 p.m. UTC | #3 
Hi Amit,

On Wed, Jul 22, 2009 at 7:55 PM, Amit
Kucheria<amit.kucheria@verdurent.com> wrote:
> On 09 Jul 20, Trilok Soni wrote:
>> Hi Vikram,
>>
>> > +
>> > +#include <linux/kernel.h>
>> > +#include <linux/module.h>
>> > +#include <linux/init.h>
>> > +#include <linux/interrupt.h>
>> > +#include <linux/input.h>
>> > +#include <linux/platform_device.h>
>> > +#include <linux/i2c/twl4030.h>
>> > +#include <mach/keypad.h>
>>
>> One empty line between above two headers.
>>
>> I hope you are aware of earlier comments posted for this driver when
>> it was submitted few months back and had long discussion on threaded
>> irq stuff.
>>
>
> Trilok,
>
> Could you please post a link to that discussion. Google isn't pointing
> me to any relevant discussions besides
> http://lkml.org/lkml/2008/10/1/334
>
> I'll do a further cleanup and resubmit.

If you follow latest discussion as below, you will get the pointers.

http://marc.info/?l=linux-i2c&m=124828117611346&w=2

It is also CCed to linux-input as well.
diff mbox

Patch

Index: linus/drivers/input/keyboard/Kconfig
===================================================================
--- linus.orig/drivers/input/keyboard/Kconfig	2009-07-17 18:24:46.000000000 -0500
+++ linus/drivers/input/keyboard/Kconfig	2009-07-17 19:10:46.000000000 -0500
@@ -259,6 +259,17 @@  config KEYBOARD_NEWTON
 	  To compile this driver as a module, choose M here: the
 	  module will be called newtonkbd.
 
+config KEYBOARD_TWL4030
+	tristate "TI TWL4030/TWL5030/TPS659x0 keypad support"
+	depends on TWL4030_CORE
+	help
+	Say Y here if your board use the keypad controller on
+	TWL4030 family chips.  It's safe to say enable this
+	even on boards that don't use the keypad controller.
+
+	To compile this driver as a module, choose M here: the
+	module will be called twl4030_keypad.
+
 config KEYBOARD_PXA27x
 	tristate "PXA27x/PXA3xx keypad support"
 	depends on PXA27x || PXA3xx
Index: linus/drivers/input/keyboard/Makefile
===================================================================
--- linus.orig/drivers/input/keyboard/Makefile	2009-07-17 18:24:46.000000000 -0500
+++ linus/drivers/input/keyboard/Makefile	2009-07-17 19:10:46.000000000 -0500
@@ -23,6 +23,7 @@  obj-$(CONFIG_KEYBOARD_MAPLE)		+= maple_k
 obj-$(CONFIG_KEYBOARD_MATRIX)		+= matrix_keypad.o
 obj-$(CONFIG_KEYBOARD_NEWTON)		+= newtonkbd.o
 obj-$(CONFIG_KEYBOARD_OMAP)		+= omap-keypad.o
+obj-$(CONFIG_KEYBOARD_TWL4030)		+= twl4030_keypad.o
 obj-$(CONFIG_KEYBOARD_PXA27x)		+= pxa27x_keypad.o
 obj-$(CONFIG_KEYBOARD_PXA930_ROTARY)	+= pxa930_rotary.o
 obj-$(CONFIG_KEYBOARD_SH_KEYSC)		+= sh_keysc.o
Index: linus/drivers/input/keyboard/twl4030_keypad.c
===================================================================
--- /dev/null	1970-01-01 00:00:00.000000000 +0000
+++ linus/drivers/input/keyboard/twl4030_keypad.c	2009-07-17 19:10:46.000000000 -0500
@@ -0,0 +1,492 @@ 
+/*
+ * twl4030_keypad.c - driver for 8x8 keypad controller in twl4030 chips
+ *
+ * Copyright (C) 2009 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>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * 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.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
+ */
+
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/init.h>
+#include <linux/interrupt.h>
+#include <linux/input.h>
+#include <linux/platform_device.h>
+#include <linux/i2c/twl4030.h>
+#include <mach/keypad.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 MAX_ROWS		8	/* TWL4030 hard limit */
+
+struct twl4030_keypad {
+	unsigned	*keymap;
+	unsigned int	keymapsize;
+	u16		kp_state[MAX_ROWS];
+	unsigned	n_rows;
+	unsigned	n_cols;
+	unsigned	irq;
+
+	struct device	*dbg_dev;
+	struct input_dev *input;
+};
+
+#define ROWCOL_MASK	KEY(0xf, 0xf, 0)
+
+/*----------------------------------------------------------------------*/
+
+/* 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;
+
+	ret = twl4030_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;
+	}
+	return ret;
+}
+
+static int twl4030_kpwrite_u8(struct twl4030_keypad *kp, u8 data, u32 reg)
+{
+	int ret;
+
+	ret = twl4030_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;
+	}
+	return ret;
+}
+
+static int twl4030_find_key(struct twl4030_keypad *kp, int col, int row)
+{
+	int i, rc;
+
+	rc = KEY(col, row, 0);
+	for (i = 0; i < kp->keymapsize; i++)
+		if ((kp->keymap[i] & ROWCOL_MASK) == rc)
+			return kp->keymap[i] & (KEYNUM_MASK | KEY_PERSISTENT);
+
+	return -EINVAL;
+}
+
+static inline u16 twl4030_col_xlate(struct twl4030_keypad *kp, u8 col)
+{
+	/* If all bits in a row are active for all coloumns then
+	 * we have that row line connected to gnd. Mark this
+	 * key on as if it was on matrix position n_cols (ie
+	 * 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[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 int 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 1;
+		check |= col;
+	}
+
+	return 0;
+}
+
+static void twl4030_kp_scan(struct twl4030_keypad *kp, int release_all)
+{
+	u16 new_state[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;
+
+		for (col = 0; col < kp->n_cols; col++) {
+			int key;
+
+			if (!(changed & (1 << col)))
+				continue;
+
+			dev_dbg(kp->dbg_dev, "key [%d:%d] %s\n", row, col,
+				(new_state[row] & (1 << col)) ?
+				"press" : "release");
+
+			key = twl4030_find_key(kp, col, row);
+			if (key < 0)
+				dev_warn(kp->dbg_dev,
+					"Spurious key event %d-%d\n",
+					 col, row);
+			else if (key & KEY_PERSISTENT)
+				continue;
+			else
+				input_report_key(kp->input, key,
+						 new_state[row] & (1 << col));
+		}
+		kp->kp_state[row] = new_state[row];
+	}
+	input_sync(kp->input);
+}
+
+/*
+ * Keypad interrupt handler
+ */
+static irqreturn_t do_kp_irq(int irq, void *_kp)
+{
+	struct twl4030_keypad *kp = _kp;
+	u8 reg;
+	int ret;
+
+#ifdef CONFIG_LOCKDEP
+	/* WORKAROUND for lockdep forcing IRQF_DISABLED on us, which
+	 * we don't want and can't tolerate.  Although it might be
+	 * friendlier not to borrow this thread context...
+	 */
+	local_irq_enable();
+#endif
+
+	/* 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, 0);
+	else
+		twl4030_kp_scan(kp, 1);
+
+	return IRQ_HANDLED;
+}
+
+/*
+ * Registers keypad device with input subsystem
+ * and configures TWL4030 keypad registers
+ */
+static int __devinit twl4030_kp_probe(struct platform_device *pdev)
+{
+	u8 reg;
+	int i;
+	int ret = 0;
+	struct twl4030_keypad *kp;
+	struct twl4030_keypad_data *pdata = pdev->dev.platform_data;
+
+	if (!pdata || !pdata->rows || !pdata->cols || !pdata->keymap
+			|| pdata->rows > 8 || pdata->cols > 8) {
+		dev_err(&pdev->dev, "Invalid platform_data\n");
+		return -EINVAL;
+	}
+
+	kp = kzalloc(sizeof(*kp), GFP_KERNEL);
+	if (!kp)
+		return -ENOMEM;
+
+	platform_set_drvdata(pdev, kp);
+
+	/* Get the debug Device */
+	kp->dbg_dev = &pdev->dev;
+
+	kp->input = input_allocate_device();
+	if (!kp->input) {
+		kfree(kp);
+		return -ENOMEM;
+	}
+
+	kp->keymap = pdata->keymap;
+	kp->keymapsize = pdata->keymapsize;
+	kp->n_rows = pdata->rows;
+	kp->n_cols = pdata->cols;
+	kp->irq = platform_get_irq(pdev, 0);
+
+	/* setup input device */
+	__set_bit(EV_KEY, kp->input->evbit);
+
+	/* Enable auto repeat feature of Linux input subsystem */
+	if (pdata->rep)
+		__set_bit(EV_REP, kp->input->evbit);
+
+	for (i = 0; i < kp->keymapsize; i++)
+		__set_bit(kp->keymap[i] & KEYNUM_MASK,
+				kp->input->keybit);
+
+	kp->input->name		= "TWL4030 Keypad";
+	kp->input->phys		= "twl4030_keypad/input0";
+	kp->input->dev.parent	= &pdev->dev;
+
+	kp->input->id.bustype	= BUS_HOST;
+	kp->input->id.vendor	= 0x0001;
+	kp->input->id.product	= 0x0001;
+	kp->input->id.version	= 0x0003;
+
+	kp->input->keycode	= kp->keymap;
+	kp->input->keycodesize	= sizeof(unsigned int);
+	kp->input->keycodemax	= kp->keymapsize;
+
+	ret = input_register_device(kp->input);
+	if (ret < 0) {
+		dev_err(kp->dbg_dev,
+			"Unable to register twl4030 keypad device\n");
+		goto err2;
+	}
+
+	/* Enable controller, with hardware decoding but not autorepeat */
+	reg = KEYP_CTRL_SOFT_NRST | KEYP_CTRL_SOFTMODEN
+		| KEYP_CTRL_TOE_EN | KEYP_CTRL_KBD_ON;
+	ret = twl4030_kpwrite_u8(kp, reg, KEYP_CTRL);
+	if (ret < 0)
+		goto err3;
+
+	/* 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;
+	ret = twl4030_kpwrite_u8(kp, reg, KEYP_EDR);
+	if (ret < 0)
+		goto err3;
+
+	/* Set PTV prescaler Field */
+	reg = (PTV_PRESCALER << KEYP_LK_PTV_PTV_SHIFT);
+	ret = twl4030_kpwrite_u8(kp, reg, KEYP_LK_PTV);
+	if (ret < 0)
+		goto err3;
+
+	/* Set key debounce time to 20 ms */
+	i = KEYP_PERIOD_US(20000, PTV_PRESCALER);
+	ret = twl4030_kpwrite_u8(kp, i, KEYP_DEB);
+	if (ret < 0)
+		goto err3;
+
+	/* Set timeout period to 100 ms */
+	i = KEYP_PERIOD_US(200000, PTV_PRESCALER);
+	ret = twl4030_kpwrite_u8(kp, (i & 0xFF), KEYP_TIMEOUT_L);
+	if (ret < 0)
+		goto err3;
+	ret = twl4030_kpwrite_u8(kp, (i >> 8), KEYP_TIMEOUT_H);
+	if (ret < 0)
+		goto err3;
+
+	/* 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;
+	ret = twl4030_kpwrite_u8(kp, reg, KEYP_SIH_CTRL);
+	if (ret < 0)
+		goto err3;
+
+	/* initialize key state; irqs update it from here on */
+	ret = twl4030_read_kp_matrix_state(kp, kp->kp_state);
+	if (ret < 0)
+		goto err3;
+
+	/*
+	 * 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 ...
+	 */
+	ret = request_irq(kp->irq, do_kp_irq, 0, pdev->name, kp);
+	if (ret < 0) {
+		dev_info(kp->dbg_dev, "request_irq failed for irq no=%d\n",
+			kp->irq);
+		goto err3;
+	} else {
+		/* Enable KP and TO interrupts now. */
+		reg = (u8) ~(KEYP_IMR1_KP | KEYP_IMR1_TO);
+		ret = twl4030_kpwrite_u8(kp, reg, KEYP_IMR1);
+		if (ret < 0)
+			goto err5;
+	}
+
+	return ret;
+err5:
+	/* mask all events - we don't care about the result */
+	(void) twl4030_kpwrite_u8(kp, 0xff, KEYP_IMR1);
+	free_irq(kp->irq, NULL);
+err3:
+	input_unregister_device(kp->input);
+	kp->input = NULL;
+err2:
+	input_free_device(kp->input);
+	kfree(kp);
+	return -ENODEV;
+}
+
+static int __devexit twl4030_kp_remove(struct platform_device *pdev)
+{
+	struct twl4030_keypad *kp = platform_get_drvdata(pdev);
+
+	free_irq(kp->irq, kp);
+	input_unregister_device(kp->input);
+	kfree(kp);
+
+	return 0;
+}
+
+/*
+ * 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).
+ */
+
+MODULE_ALIAS("platform:twl4030_keypad");
+
+static struct platform_driver twl4030_kp_driver = {
+	.probe		= twl4030_kp_probe,
+	.remove		= __devexit_p(twl4030_kp_remove),
+	.driver		= {
+		.name	= "twl4030_keypad",
+		.owner	= THIS_MODULE,
+	},
+};
+
+static int __init twl4030_kp_init(void)
+{
+	return platform_driver_register(&twl4030_kp_driver);
+}
+module_init(twl4030_kp_init);
+
+static void __exit twl4030_kp_exit(void)
+{
+	platform_driver_unregister(&twl4030_kp_driver);
+}
+module_exit(twl4030_kp_exit);
+
+MODULE_AUTHOR("Texas Instruments");
+MODULE_DESCRIPTION("TWL4030 Keypad Driver");
+MODULE_LICENSE("GPL");