Re: [PATCHv2 2/4] Input: keypad: Add smsc ece1099 keypad driver

From: Poddar, Sourav
Date: Thu Sep 06 2012 - 01:38:51 EST

+ other external mailing list (did a reply to by mistake)

On Thu, Sep 6, 2012 at 11:04 AM, Poddar, Sourav <sourav.poddar@xxxxxx> wrote:
> Hi Vaibhav,
>
> On Thu, Sep 6, 2012 at 12:01 AM, Vaibhav Hiremath <hvaibhav@xxxxxx> wrote:
>>
>>
>> On 9/5/2012 5:06 PM, Sourav Poddar wrote:
>>> From: G, Manjunath Kondaiah <manjugk@xxxxxx>
>>>
>>> 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.
>>>
>>> Cc: Dmitry Torokhov <dmitry.torokhov@xxxxxxxxx>
>>> Cc: Benoit Cousson <b-cousson@xxxxxx>
>>> Cc: Felipe Balbi <balbi@xxxxxx>
>>> Cc: Santosh Shilimkar <santosh.shilimkar@xxxxxx>
>>> Signed-off-by: G, Manjunath Kondaiah <manjugk@xxxxxx>
>>> Signed-off-by: Sourav Poddar <sourav.poddar@xxxxxx>
>>> Acked-by: Felipe Balbi <balbi@xxxxxx>
>>> ---
>>> Changes since v1:
>>> - Prevent the use of kfree since devm_kzalloc was used.
>>> - Use devexit around remove api
>>> drivers/input/keyboard/Kconfig | 11 +
>>> drivers/input/keyboard/Makefile | 1 +
>>> drivers/input/keyboard/smsc-ece1099-keypad.c | 306 ++++++++++++++++++++++++++
>>> 3 files changed, 318 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..2a2d374 100644
>>> --- a/drivers/input/keyboard/Kconfig
>>> +++ b/drivers/input/keyboard/Kconfig
>>> @@ -593,6 +593,17 @@ 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=y
>>
>> Any specific reason behind "=y"
>>
> Nope, my bad.."=y" should be dropped.
>>> + 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..71cd7d6
>>> --- /dev/null
>>> +++ b/drivers/input/keyboard/smsc-ece1099-keypad.c
>>> @@ -0,0 +1,306 @@
>>> +/*
>>> + * 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;
>>> + struct matrix_keymap_data *keymap_data;
>>> + 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;
>>> + 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;
>>> + }
>>> + }
>>> + 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;
>>
>> Isn't you should return -ENXIO?
>>
> I think "EINVAL" is more apt as it will reflect that the user has not populated
> the dt data and its an invalid argument.
>>> + }
>>> +
>>> + 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_get_property(np, "linux,input-no-autorepeat", NULL))
>>> + kp->no_autorepeat = true;
>>> +
>>
>> You can use of_property_read_bool() here.
>>
> Ok.Will change.
>>> + 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, error;
>>> + int col, i, max_keys, row_shift;
>>> + int irq;
>>> + int addr_start, addr;
>>> +
>>> + kp = devm_kzalloc(dev, sizeof(*kp), GFP_KERNEL);
>>> +
>>> + input = input_allocate_device();
>>> + if (!kp || !input) {
>>> + error = -ENOMEM;
>>> + goto err1;
>>
>> You can directly return here.
>>
> Ok.
>>> + }
>>> +
>>> + error = smsc_keypad_parse_dt(&pdev->dev, kp);
>>> + if (error)
>>> + return error;
>>> +
>>> + /* Get the debug Device */
>>> + kp->input = input;
>>> + kp->smsc = smsc;
>>> + kp->irq = platform_get_irq(pdev, 0);
>>> + kp->dev = dev;
>>> +
>>> + for (col = 0; col < 16; col++) {
>>
>> Isn't this magic no 16 should come from DT??
>>
> Yes, actually its the number of columns which is coming from
> dt only. I will replace it with the correct variable containg this data.
>>
>>> + kp->last_key_state[col] = 0;
>>> + kp->last_key_ms[col] = 0;
>>> + }
>>> +
>>> + /* 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;
>>> +
>>> + error = input_register_device(input);
>>> + if (error) {
>>> + dev_err(kp->dev,
>>> + "Unable to register twl4030 keypad device\n");
>>> + goto err1;
>>> + }
>>> +
>>> + /* Mask all GPIO interrupts (0x37-0x3B) */
>>> + for (addr = 0x37; addr < 0x3B; addr++)
>>> + smsc_write(dev, addr, 0);
>>> +
>>> + /* Set all outputs high (0x05-0x09) */
>>> + for (addr = 0x05; addr < 0x09; addr++)
>>> + smsc_write(dev, addr, 0xff);
>>> +
>>> + /* Clear all GPIO interrupts (0x32-0x36) */
>>> + for (addr = 0x32; addr < 0x36; addr++)
>>> + smsc_write(dev, addr, 0xff);
>>> +
>>> + addr_start = 0x12;
>>> + for (i = 0; i <= kp->rows; i++) {
>>> + addr = 0x12 + i;
>>> + smsc_write(dev, addr, SMSC_KP_KSI);
>>> + }
>>> +
>>> + addr_start = 0x1A;
>>> + for (i = 0; i <= kp->cols; i++) {
>>> + addr = 0x1A + i;
>>> + smsc_write(dev, addr, SMSC_KP_KSO);
>>> + }
>>> +
>>
>> Lots of magic numbers without proper description/comments.
>>
> I will try to put comments or replace the magic numbers with the
> macros declared in .h file.
>>> + addr = SMSC_KP_INT_STAT;
>>> + smsc_write(dev, addr, SMSC_KP_SET_HIGH);
>>> +
>>> + addr = SMSC_WKUP_CTRL;
>>> + smsc_write(dev, addr, SMSC_KP_SET_LOW_PWR);
>>> +
>>> + addr = SMSC_KP_OUT;
>>> + smsc_write(dev, addr, SMSC_KSO_ALL_LOW);
>>> +
>>
>> I didn't understand why to initialize 'addr' and pass it, why can't you
>> directly pass it as a argument?
>>
> Actually Yes, addr can be directly replaced with the corresponding address.
>>> + row_shift = get_count_order(kp->cols);
>>> + max_keys = kp->rows << row_shift;
>>> +
>>> + kp->row_shift = row_shift;
>>> + kp->keymap = kzalloc(max_keys * sizeof(kp->keymap[0]),
>>> + GFP_KERNEL);
>>> + if (!kp->keymap) {
>>> + dev_err(&pdev->dev, "Not enough memory for keymap\n");
>>> + error = -ENOMEM;
>>> + }
>>> +
>>> + matrix_keypad_build_keymap(NULL, NULL, kp->rows,
>>> + kp->cols, kp->keymap, input);
>>> +
>>> + /*
>>> + * 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 err2;
>>> + }
>>> +
>>> + /* Enable smsc keypad interrupts */
>>> + ret = smsc_write(dev, SMSC_KP_INT_MASK, 0xff);
>>> + if (ret < 0)
>>> + goto err2;
>>> +
>>> + return 0;
>>> +
>>> +err2:
>>> + input_unregister_device(input);
>>> +err1:
>>> + input_free_device(input);
>>
>> You are not freeing memory allocated for kp->keymap. Please use devm_
>> variants.
>>
> True. Will do.
>> Thanks,
>> Vaibhav
>>> + return ret;
>>> +}
>>> +
>>> +static int __devexit smsc_remove(struct platform_device *pdev)
>>> +{
>>> + struct smsc_keypad *kp = platform_get_drvdata(pdev);
>>> + input_unregister_device(kp->input);
>>> +
>>> + return 0;
>>> +}
>>> +
>>> +#ifdef CONFIG_OF
>>> +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 <manjugk@xxxxxx>");
>>> +MODULE_DESCRIPTION("SMSC ECE1099 Keypad driver");
>>> +MODULE_LICENSE("GPL v2");
>>>
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