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

Poddar, Sourav sourav.poddar at ti.com
Thu Sep 6 01:38:45 EDT 2012


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

On Thu, Sep 6, 2012 at 11:04 AM, Poddar, Sourav <sourav.poddar at ti.com> wrote:
> Hi Vaibhav,
>
> On Thu, Sep 6, 2012 at 12:01 AM, Vaibhav Hiremath <hvaibhav at ti.com> wrote:
>>
>>
>> On 9/5/2012 5:06 PM, Sourav Poddar wrote:
>>> From: G, Manjunath Kondaiah <manjugk at ti.com>
>>>
>>> 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 at gmail.com>
>>> Cc: Benoit Cousson <b-cousson at ti.com>
>>> Cc: Felipe Balbi <balbi at ti.com>
>>> Cc: Santosh Shilimkar <santosh.shilimkar at ti.com>
>>> Signed-off-by: G, Manjunath Kondaiah <manjugk at ti.com>
>>> Signed-off-by: Sourav Poddar <sourav.poddar at ti.com>
>>> Acked-by: Felipe Balbi <balbi at ti.com>
>>> ---
>>> 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 at ti.com>");
>>> +MODULE_DESCRIPTION("SMSC ECE1099 Keypad driver");
>>> +MODULE_LICENSE("GPL v2");
>>>



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