[PATCHv3 2/4] Input: keypad: Add smsc ece1099 keypad driver

Poddar, Sourav sourav.poddar at ti.com
Wed Oct 3 01:56:46 EDT 2012


Hi Dmitry,

On Tue, Oct 2, 2012 at 11:48 AM, Dmitry Torokhov
<dmitry.torokhov at gmail.com> wrote:
> Hi Sourav,
>
> On Mon, Oct 01, 2012 at 04:31:50PM +0530, 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.
>>
>> Tested on omap5430 evm with 3.6-rc6 custom kernel.
>>
>> 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 v2:
>>  - Replace magic numbers through driver variable.
>>  - Provide comments for some initialisation done in probe.
>>  drivers/input/keyboard/Kconfig               |   11 +
>>  drivers/input/keyboard/Makefile              |    1 +
>>  drivers/input/keyboard/smsc-ece1099-keypad.c |  304 ++++++++++++++++++++++++++
>>  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..b03a39c 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"
>
> Should also select INPUT_MATRIXKMAP.
>
Yes, will include in the next version.
>> +       depends on I2C
>> +       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..15dc147
>> --- /dev/null
>> +++ b/drivers/input/keyboard/smsc-ece1099-keypad.c
>> @@ -0,0 +1,304 @@
>> +/*
>> + * 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;
>> +     }
>> +
>> +     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, error;
>> +     int col, i, max_keys, row_shift;
>> +     int irq;
>> +     int addr;
>> +
>> +     kp = devm_kzalloc(dev, sizeof(*kp), GFP_KERNEL);
>> +
>> +     input = input_allocate_device();
>> +     if (!kp || !input) {
>> +             error = -ENOMEM;
>> +             goto err1;
>> +     }
>> +
>> +     error = smsc_keypad_parse_dt(&pdev->dev, kp);
>
> It doe snot look like the driver is useful without DT... Should it
> simply depend on OF and not even provide !OF stubs?
>
Yes, the idea was to make this driver completely dt specific.

>> +     if (error)
>
> You are leaking input device here.
>
True, will include appropriate goto label.
>> +             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++) {
>> +             kp->last_key_state[col] = 0;
>> +             kp->last_key_ms[col] = 0;
>
> kzalloc should have already taken care of this.
>
Ok. Will remove.
>> +     }
>> +
>> +     /* setup input device */
>> +      __set_bit(EV_KEY, input->evbit);
>> +
>> +     /* Enable auto repeat feature of Linux input subsystem */
>> +     if (!(kp->no_autorepeat))
>
> No need for extra parenthesis.
>
Will remove.
>> +             __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 = 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);
>> +
>> +     /* Configure the smsc pins as Keyboard scan Input */
>> +     for (i = 0; i <= kp->rows; i++) {
>> +             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");
>> +             error = -ENOMEM;
>> +     }
>> +
>> +     matrix_keypad_build_keymap(NULL, NULL, kp->rows,
>> +                     kp->cols, kp->keymap, input);
>
> Needs error handling I believe.
>
True, missed that. Will include.
>> +
>> +     /*
>> +     * 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);
>
> Double free.
>
I believe what you are trying to say here is that we dont really
need a " input_unregister_device" (as also I checked in other keypad
implementations) and do a "unregister_device" in the remove api ??
>> +     return ret;
>> +}
>> +
>> +static int __devexit smsc_remove(struct platform_device *pdev)
>> +{
>> +     struct smsc_keypad *kp = platform_get_drvdata(pdev);
>> +     input_unregister_device(kp->input);
>
> And your kernel goes *BOOM*
>
>> +
>> +     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");
>> --
>> 1.7.1
>>
>
> Thanks.
>
> --
> Dmitry



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