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

From: Dmitry Torokhov
Date: Tue Oct 02 2012 - 03:11:21 EST


Hi Sourav,

On Mon, Oct 01, 2012 at 04:31:50PM +0530, 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.
>
> Tested on omap5430 evm with 3.6-rc6 custom kernel.
>
> 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 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.

> + 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?

> + if (error)

You are leaking input device here.

> + 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.

> + }
> +
> + /* 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.

> + __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.

> +
> + /*
> + * 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.

> + 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@xxxxxx>");
> +MODULE_DESCRIPTION("SMSC ECE1099 Keypad driver");
> +MODULE_LICENSE("GPL v2");
> --
> 1.7.1
>

Thanks.

--
Dmitry
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