Subject: [PATCHv4] Input: keypad: Add smsc ece1099 keypad driver

From: [email-masked] (Sourav)
Date: Thu, 25 Oct 2012 14:47:09 +0530

Hi Dmitry,
On Wednesday 24 October 2012 12:05 PM, Dmitry Torokhov wrote:
> Hi Sourav,
>
> On Fri, Oct 05, 2012 at 12:56:26PM +0530, Sourav Poddar wrote:
>> From: G, Manjunath Kondaiah <[email-masked]>
>>
>> SMSC ECE1099 is a keyboard scan or GPIO expansion device.The device
>> supports a keypad scan matrix of 23*8.This driver uses this
>> device as a keypad driver.
>>
>> Tested on omap5430 evm with 3.6-rc6 custom kernel.
>>
>> Cc: Benoit Cousson <[email-masked]>
>> Cc: Felipe Balbi <[email-masked]>
>> Cc: Santosh Shilimkar <[email-masked]>
>> Signed-off-by: G, Manjunath Kondaiah <[email-masked]>
>> Signed-off-by: Sourav Poddar <[email-masked]>
>> Acked-by: Felipe Balbi <[email-masked]>
>> ---
>> This patch was posted as a series initially
>> http://www.spinics.net/lists/linux-omap/msg78772.html
>>
>> But the parent mfd driver has beeen already picked by mfd maintainer.
>> So this patch can now posted as an standalone patch.
>>
>> v3->v4:
>> Fix Dmitry's comments:
>>   - Error patch(input_free_device/input_unregister_device).
>>   - Few cleanups.
>>   - Included INPUT_MATRIXKMAP
>>   drivers/input/keyboard/Kconfig               |   12 +
>>   drivers/input/keyboard/Makefile              |    1 +
>>   drivers/input/keyboard/smsc-ece1099-keypad.c |  303 ++++++++++++++++++++++++++
>>   3 files changed, 316 insertions(+), 0 deletions(-)
>>   create mode 100644 drivers/input/keyboard/smsc-ece1099-keypad.c
>>
>> diff --git a/drivers/input/keyboard/Kconfig b/drivers/input/keyboard/Kconfig
>> index c50fa75..e370b03 100644
>> --- a/drivers/input/keyboard/Kconfig
>> +++ b/drivers/input/keyboard/Kconfig
>> @@ -593,6 +593,18 @@ config KEYBOARD_TWL4030
>>   	  To compile this driver as a module, choose M here: the
>>   	  module will be called twl4030_keypad.
>>   
>> +config KEYBOARD_SMSC
>> +       tristate "SMSC ECE1099 keypad support"
>> +       depends on I2C
>> +       select INPUT_MATRIXKMAP
> While I do not see hard dependencies in the driver itself, should we
> also depend on MFD_SMSC?
Ahh, may be yes. This driver will get probed only after parent driver 
get probed.
So may be we can follow the same order for building also.
>> +       help
>> +         Say Y here if your board use the smsc keypad controller
>> +         for omap5 defconfig. 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 smsc-ece1099-keypad.
>> +
>>   config KEYBOARD_XTKBD
>>   	tristate "XT keyboard"
>>   	select SERIO
>> diff --git a/drivers/input/keyboard/Makefile b/drivers/input/keyboard/Makefile
>> index 44e7600..0f2aa26 100644
>> --- a/drivers/input/keyboard/Makefile
>> +++ b/drivers/input/keyboard/Makefile
>> @@ -52,5 +52,6 @@ obj-$(CONFIG_KEYBOARD_TC3589X)		+= tc3589x-keypad.o
>>   obj-$(CONFIG_KEYBOARD_TEGRA)		+= tegra-kbc.o
>>   obj-$(CONFIG_KEYBOARD_TNETV107X)	+= tnetv107x-keypad.o
>>   obj-$(CONFIG_KEYBOARD_TWL4030)		+= twl4030_keypad.o
>> +obj-$(CONFIG_KEYBOARD_SMSC)            += smsc-ece1099-keypad.o
>>   obj-$(CONFIG_KEYBOARD_XTKBD)		+= xtkbd.o
>>   obj-$(CONFIG_KEYBOARD_W90P910)		+= w90p910_keypad.o
>> diff --git a/drivers/input/keyboard/smsc-ece1099-keypad.c b/drivers/input/keyboard/smsc-ece1099-keypad.c
>> new file mode 100644
>> index 0000000..a4a0dfe
>> --- /dev/null
>> +++ b/drivers/input/keyboard/smsc-ece1099-keypad.c
>> @@ -0,0 +1,303 @@
>> +/*
>> + * SMSC_ECE1099 Keypad driver
>> + *
>> + * Copyright (C) 2012 Texas Instruments Incorporated - http://www.ti.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.
>> + */
>> +
>> +#include <linux/i2c.h>
>> +#include <linux/kernel.h>
>> +#include <linux/module.h>
>> +#include <linux/init.h>
>> +#include <linux/interrupt.h>
>> +#include <linux/input.h>
>> +#include <linux/gpio.h>
>> +#include <linux/slab.h>
>> +#include <linux/jiffies.h>
>> +#include <linux/input/matrix_keypad.h>
>> +#include <linux/delay.h>
>> +#include <linux/mfd/core.h>
>> +#include <linux/mfd/smsc.h>
>> +#include <linux/of_gpio.h>
>> +#include <linux/of.h>
>> +
>> +#define KEYPRESS_TIME          200
>> +
>> +struct smsc_keypad {
>> +	struct smsc *smsc;
> I do not see this being actually used.
Yes, will remove.
>> +	struct matrix_keymap_data *keymap_data;
> Does not seem to be used.
Yes, will remove.
>> +	unsigned int last_key_state[16];
>> +	unsigned int last_col;
>> +	unsigned int last_key_ms[16];
>> +	unsigned short *keymap;
>> +	struct i2c_client *client;
>> +	struct input_dev *input;
>> +	int rows, cols;
>> +	int row_shift;
>> +	bool no_autorepeat;
>> +	unsigned        irq;
> I do not think you need to store irq if you are using managed resources.
>
Don't, we need some variable to keep the irq number received after parsing
the dt data.? This variable is basically used as a parameter in 
"request_irq" api.
I saw the patch on omap4_keypad switching to managed resource, and there 
also we are
keeping the keypad_data->irq intact??
>> +	struct device *dev;
>> +};
>> +
>> +static void smsc_kp_scan(struct smsc_keypad *kp)
>> +{
>> +	struct input_dev *input = kp->input;
>> +	int i, j;
>> +	int row, col;
>> +	int temp, code;
>> +	unsigned int new_state[16];
>> +	unsigned int bits_changed;
>> +	int this_ms;
>> +
>> +	smsc_write(kp->dev, SMSC_KP_INT_MASK, 0x00);
>> +	smsc_write(kp->dev, SMSC_KP_INT_STAT, 0xFF);
>> +
>> +	/* Scan for row and column */
>> +	for (i = 0; i < kp->cols; i++) {
>> +		smsc_write(kp->dev, SMSC_KP_OUT, SMSC_KSO_EVAL + i);
>> +		/* Read Row Status */
>> +		smsc_read(kp->dev, SMSC_KP_IN, &temp);
>> +		if (temp == 0xFF)
>> +			continue;
>> +
>> +		col = i;
>> +		for (j = 0; j < kp->rows; j++) {
>> +			if ((temp & 0x01) != 0x00) {
>> +				temp = temp >> 1;
>> +				continue;
>> +			}
>> +
>> +			row = j;
>> +			new_state[col] =  (1 << row);
>> +			bits_changed = kp->last_key_state[col] ^ new_state[col];
>> +			this_ms = jiffies_to_msecs(jiffies);
>> +			if (bits_changed != 0 || (!bits_changed &&
>> +					((this_ms - kp->last_key_ms[col]) >= KEYPRESS_TIME))) {
>> +				code = MATRIX_SCAN_CODE(row, col, kp->row_shift);
>> +				input_event(input, EV_MSC, MSC_SCAN, code);
>> +				input_report_key(input, kp->keymap[code], 1);
>> +				input_report_key(input, kp->keymap[code], 0);
>> +				kp->last_key_state[col] = new_state[col];
>> +				if (kp->last_col != col)
>> +					kp->last_key_state[kp->last_col] = 0;
>> +				kp->last_key_ms[col] = this_ms;
>> +			}
>> +			temp = temp >> 1;
>> +		}
>
> Maybe split inner loop into separate function?
Ok.
>> +	}
>> +	input_sync(input);
>> +
>> +	smsc_write(kp->dev, SMSC_KP_INT_MASK, 0xFF);
>> +
>> +	/* Set up Low Power Mode (Wake-up) (0xFB) */
>> +	smsc_write(kp->dev, SMSC_WKUP_CTRL, SMSC_KP_SET_LOW_PWR);
>> +
>> +	/*Enable Keypad Scan (generate interrupt on key press) (0x40)*/
>> +	smsc_write(kp->dev, SMSC_KP_OUT, SMSC_KSO_ALL_LOW);
>> +}
>> +
>> +static irqreturn_t do_kp_irq(int irq, void *_kp)
>> +{
>> +	struct smsc_keypad *kp = _kp;
>> +	int int_status;
>> +
>> +	smsc_read(kp->dev, SMSC_KP_INT_STAT, &int_status);
>> +	if (int_status)
>> +		smsc_kp_scan(kp);
>> +
>> +	return IRQ_HANDLED;
>> +}
>> +
>> +#ifdef CONFIG_OF
>> +static int __devinit smsc_keypad_parse_dt(struct device *dev,
>> +				struct smsc_keypad *kp)
>> +{
>> +	struct device_node *np = dev->of_node;
>> +
>> +	if (!np) {
>> +		dev_err(dev, "missing DT data");
>> +		return -EINVAL;
>> +	}
>> +
>> +	of_property_read_u32(np, "keypad,num-rows", &kp->rows);
>> +	of_property_read_u32(np, "keypad,num-columns", &kp->cols);
>> +	if (!kp->rows || !kp->cols) {
>> +		dev_err(dev, "number of keypad rows/columns not specified\n");
>> +		return -EINVAL;
>> +	}
>> +
>> +	if (of_property_read_bool(np, "linux,input-no-autorepeat"))
>> +		kp->no_autorepeat = true;
>> +
>> +	return 0;
>> +}
>> +#else
>> +static inline int smsc_keypad_parse_dt(struct device *dev,
>> +				struct smsc_keypad *kp)
>> +{
>> +	return -ENOSYS;
>> +}
>> +#endif
>> +
>> +static int __devinit
>> +smsc_probe(struct platform_device *pdev)
>> +{
>> +	struct device *dev = &pdev->dev;
>> +	struct smsc *smsc = dev_get_drvdata(pdev->dev.parent);
>> +	struct input_dev *input;
>> +	struct smsc_keypad *kp;
>> +	int ret = 0;
>> +	int i, max_keys, row_shift;
>> +	int irq;
>> +	int addr;
>> +
>> +	kp = devm_kzalloc(dev, sizeof(*kp), GFP_KERNEL);
>> +
>> +	input = input_allocate_device();
>> +	if (!kp || !input) {
>> +		ret = -ENOMEM;
>> +		goto err1;
>> +	}
>> +
>> +	ret = smsc_keypad_parse_dt(&pdev->dev, kp);
>> +	if (ret)
>> +		goto err1;
> So this is pure-DT driver. Please add Kconfig dependency on OF, drop
> #ifdef guards and the stub.
Ok.
>> +
>> +	/* Get the debug Device */
>> +	kp->input = input;
>> +	kp->smsc = smsc;
>> +	kp->irq = platform_get_irq(pdev, 0);
>> +	kp->dev = dev;
>> +
>> +	/* setup input device */
>> +	 __set_bit(EV_KEY, input->evbit);
>> +
>> +	/* Enable auto repeat feature of Linux input subsystem */
>> +	if (!kp->no_autorepeat)
>> +		__set_bit(EV_REP, input->evbit);
>> +
>> +	input_set_capability(input, EV_MSC, MSC_SCAN);
>> +	input->name             = "SMSC Keypad";
>> +	input->phys             = "smsc_keypad/input0";
>> +	input->dev.parent       = &pdev->dev;
>> +	input->id.bustype       = BUS_HOST;
>> +	input->id.vendor        = 0x0001;
>> +	input->id.product       = 0x0001;
>> +	input->id.version       = 0x0003;
>> +
>> +	/* Mask all GPIO interrupts (0x37-0x3B) */
>> +	for (addr = SMSC_GPIO_INT_MASK_START;
>> +			addr < SMSC_GPIO_INT_MASK_START + 4; addr++)
>> +		smsc_write(dev, addr, 0);
>> +
>> +	/* Set all outputs high (0x05-0x09) */
>> +	for (addr = SMSC_GPIO_DATA_OUT_START;
>> +			addr < SMSC_GPIO_DATA_OUT_START + 4; addr++)
>> +		smsc_write(dev, addr, 0xff);
>> +
>> +	/* Clear all GPIO interrupts (0x32-0x36) */
>> +	for (addr = SMSC_GPIO_INT_STAT_START;
>> +			addr < SMSC_GPIO_INT_STAT_START + 4; addr++)
>> +		smsc_write(dev, addr, 0xff);
> You use lowercase hex digits here but also uppercase in other parts of
> the driver. Can we use lowercase throughout please?
Will do.
>> +
>> +	/* Configure the smsc pins as Keyboard scan Input */
>> +	for (i = 0; i <= kp->rows; i++) {
> You sure you don't want < instead of <= ?
>
Really, "=" should not be there.
>> +		addr = 0x12 + i;
>> +		smsc_write(dev, addr, SMSC_KP_KSI);
>> +	}
>> +
>> +	/* Configure the smsc pins as Keyboard scan output */
>> +	for (i = 0; i <= kp->cols; i++) {
>> +		addr = 0x1A + i;
>> +		smsc_write(dev, addr, SMSC_KP_KSO);
>> +	}
>> +
>> +	smsc_write(dev, SMSC_KP_INT_STAT, SMSC_KP_SET_HIGH);
>> +	smsc_write(dev, SMSC_WKUP_CTRL, SMSC_KP_SET_LOW_PWR);
>> +	smsc_write(dev, SMSC_KP_OUT, SMSC_KSO_ALL_LOW);
>> +
>> +	row_shift = get_count_order(kp->cols);
>> +	max_keys = kp->rows << row_shift;
>> +
>> +	kp->row_shift = row_shift;
>> +	kp->keymap = devm_kzalloc(dev, max_keys * sizeof(kp->keymap[0]),
>> +					GFP_KERNEL);
>> +	if (!kp->keymap) {
>> +		dev_err(&pdev->dev, "Not enough memory for keymap\n");
>> +		ret = -ENOMEM;
>> +	}
>> +
>> +	ret = matrix_keypad_build_keymap(NULL, NULL, kp->rows,
>> +			kp->cols, kp->keymap, input);
>> +	if (ret) {
>> +		dev_err(&pdev->dev, "failed to build keymap\n");
>> +		goto err1;
>> +	}
>> +
>> +	/*
>> +	* This ISR will always execute in kernel thread context because of
>> +	* the need to access the SMSC over the I2C bus.
>> +	*/
>> +	ret = devm_request_threaded_irq(dev, kp->irq, NULL, do_kp_irq,
>> +			IRQF_TRIGGER_FALLING | IRQF_ONESHOT, pdev->name, kp);
>> +	if (ret) {
>> +		dev_dbg(&pdev->dev, "request_irq failed for irq no=%d\n",
>> +			irq);
>> +		goto err1;
>> +	}
>> +
>> +	/* Enable smsc keypad interrupts */
>> +	ret = smsc_write(dev, SMSC_KP_INT_MASK, 0xff);
>> +	if (ret < 0)
>> +		goto err2;
> Consider implementing ->open() and ->close() and putting the above
> there.
Ok.
>> +
>> +	ret = input_register_device(input);
>> +	if (ret) {
>> +		dev_err(kp->dev,
>> +			"Unable to register twl4030 keypad device\n");
>> +		goto err2;
>> +	}
>> +
>> +	return 0;
>> +
>> +err2:
>> +	free_irq(kp->irq, kp);
> If you allocate IRQ with devm_request_threaded_irq then you should free
> it with devm_free_irq().
Ok. Will change.
>> +err1:
>> +	input_free_device(input);
>> +	return ret;
>> +}
>> +
>> +static int __devexit smsc_remove(struct platform_device *pdev)
>> +{
>> +	struct smsc_keypad *kp = platform_get_drvdata(pdev);
>> +	input_unregister_device(kp->input);
> This is wrong: input device is gone but IRQs are still active. You need
> to disable or free IRQ first.
>
> However I just posted a patch adding support for managed input devices:
>
> 	http://www.spinics.net/lists/linux-input/msg23077.html
>
> so please either switch over, or go with unmanaged resources
> throughout.
Will switch to the managed protocol throughout.
>> +
>> +	return 0;
>> +}
>> +
>> +#ifdef CONFIG_OF
> Since we require DT this ifdef is not needed.
Will remove.
>> +static const struct of_device_id smsc_keypad_dt_match[] = {
>> +	{ .compatible = "smsc,keypad" },
>> +	{},
>> +};
>> +MODULE_DEVICE_TABLE(of, smsc_keypad_dt_match);
>> +#endif
>> +
>> +static struct platform_driver smsc_driver = {
>> +	.driver = {
>> +		.name	= "smsc-keypad",
>> +		.of_match_table = of_match_ptr(smsc_keypad_dt_match),
>> +		.owner  = THIS_MODULE,
>> +	},
>> +	.probe		= smsc_probe,
>> +	.remove		= __devexit_p(smsc_remove),
>> +};
>> +
>> +module_platform_driver(smsc_driver);
>> +
>> +MODULE_AUTHOR("G Kondaiah Manjunath <[email-masked]>");
>> +MODULE_DESCRIPTION("SMSC ECE1099 Keypad driver");
>> +MODULE_LICENSE("GPL v2");
>> -- 
>> 1.7.1
>>
> Thanks.
>