Re: [RFC] [PATCH 1/3] OMAP4: Keyboard Controller Support

Dmitry Torokhov
2010-04-21T06:55:50Z

Hi Abraham,

On Tue, Apr 13, 2010 at 08:10:48PM -0500, Arce, Abraham wrote:
> Keyboard controller for OMAP4 with built-in scanning algorithm.
> The following implementations are used:
>
> - matrix_keypac.c logic
> - hwmod framework
> - threaded irq
>
> Signed-off-by: Syed Rafiuddin <rafiuddin.syed@ti.com>
> Signed-off-by: Abraham Arce <x0066660@ti.com>
> ---
> drivers/input/keyboard/Kconfig | 9 +
> drivers/input/keyboard/Makefile | 1 +
> drivers/input/keyboard/omap4-keypad.c | 367 +++++++++++++++++++++++++++++++++
> 3 files changed, 377 insertions(+), 0 deletions(-)
> create mode 100644 drivers/input/keyboard/omap4-keypad.c
>
> diff --git a/drivers/input/keyboard/Kconfig b/drivers/input/keyboard/Kconfig
> index 5049c3c..8a4103e 100644
> --- a/drivers/input/keyboard/Kconfig
> +++ b/drivers/input/keyboard/Kconfig
> @@ -390,6 +390,15 @@ config KEYBOARD_OMAP
> To compile this driver as a module, choose M here: the
> module will be called omap-keypad.
>
> +config KEYBOARD_OMAP4
> + tristate "TI OMAP4 keypad support"
> + depends on (ARCH_OMAP4)
> + help
> + Say Y here if you want to use the OMAP4 keypad.
> +
> + To compile this driver as a module, choose M here: the
> + module will be called omap4-keypad.
> +
> config KEYBOARD_TWL4030
> tristate "TI TWL4030/TWL5030/TPS659x0 keypad support"
> depends on TWL4030_CORE
> diff --git a/drivers/input/keyboard/Makefile b/drivers/input/keyboard/Makefile
> index 78654ef..1b3dfbe 100644
> --- a/drivers/input/keyboard/Makefile
> +++ b/drivers/input/keyboard/Makefile
> @@ -27,6 +27,7 @@ obj-$(CONFIG_KEYBOARD_MATRIX) += matrix_keypad.o
> obj-$(CONFIG_KEYBOARD_MAX7359) += max7359_keypad.o
> obj-$(CONFIG_KEYBOARD_NEWTON) += newtonkbd.o
> obj-$(CONFIG_KEYBOARD_OMAP) += omap-keypad.o
> +obj-$(CONFIG_KEYBOARD_OMAP4) += omap4-keypad.o
> obj-$(CONFIG_KEYBOARD_OPENCORES) += opencores-kbd.o
> obj-$(CONFIG_KEYBOARD_PXA27x) += pxa27x_keypad.o
> obj-$(CONFIG_KEYBOARD_PXA930_ROTARY) += pxa930_rotary.o
> diff --git a/drivers/input/keyboard/omap4-keypad.c b/drivers/input/keyboard/omap4-keypad.c
> new file mode 100644
> index 0000000..b656b4f
> --- /dev/null
> +++ b/drivers/input/keyboard/omap4-keypad.c
> @@ -0,0 +1,367 @@
> +/*
> + * linux/drivers/input/keyboard/omap4-keypad.c
> + *
> + * OMAP4 Keypad Driver
> + *
> + * Copyright (C) 2010 Texas Instruments
> + *
> + * Author: Abraham Arce <x0066660@ti.com>
> + * Initial Code: Syed Rafiuddin <rafiuddin.syed@ti.com>
> + *
> + * This program is free software; you can redistribute it and/or modify
> + * it under the terms of the GNU General Public License as published by
> + * the Free Software Foundation; either version 2 of the License, or
> + * (at your option) any later version.
> + *
> + * This program is distributed in the hope that it will be useful,
> + * but WITHOUT ANY WARRANTY; without even the implied warranty of
> + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
> + * GNU General Public License for more details.
> + *
> + * You should have received a copy of the GNU General Public License
> + * along with this program; if not, write to the Free Software
> + * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
> + */
> +
> +#include <linux/module.h>
> +#include <linux/init.h>
> +#include <linux/interrupt.h>
> +#include <linux/platform_device.h>
> +#include <linux/errno.h>
> +#include <linux/io.h>
> +#include <linux/input.h>
> +#include <linux/input/matrix_keypad.h>
> +#include <plat/omap_hwmod.h>
> +#include <plat/omap_device.h>
> +
> +/* OMAP4 registers */
> +#define OMAP4_KBD_REVISION 0x00
> +#define OMAP4_KBD_SYSCONFIG 0x10
> +#define OMAP4_KBD_SYSSTATUS 0x14
> +#define OMAP4_KBD_IRQSTATUS 0x18
> +#define OMAP4_KBD_IRQENABLE 0x1C
> +#define OMAP4_KBD_WAKEUPENABLE 0x20
> +#define OMAP4_KBD_PENDING 0x24
> +#define OMAP4_KBD_CTRL 0x28
> +#define OMAP4_KBD_DEBOUNCINGTIME 0x2C
> +#define OMAP4_KBD_LONGKEYTIME 0x30
> +#define OMAP4_KBD_TIMEOUT 0x34
> +#define OMAP4_KBD_STATEMACHINE 0x38
> +#define OMAP4_KBD_ROWINPUTS 0x3C
> +#define OMAP4_KBD_COLUMNOUTPUTS 0x40
> +#define OMAP4_KBD_FULLCODE31_0 0x44
> +#define OMAP4_KBD_FULLCODE63_32 0x48
> +
> +/* OMAP4 bit definitions */
> +#define OMAP4_DEF_SYSCONFIG_SOFTRST (1 << 1)
> +#define OMAP4_DEF_SYSCONFIG_ENAWKUP (1 << 2)
> +#define OMAP4_DEF_IRQENABLE_EVENTEN (1 << 0)
> +#define OMAP4_DEF_IRQENABLE_LONGKEY (1 << 1)
> +#define OMAP4_DEF_IRQENABLE_TIMEOUTEN (1 << 2)
> +#define OMAP4_DEF_CTRL_NOSOFTMODE (1 << 1)
> +#define OMAP4_DEF_CTRLPTVVALUE (1 << 2)
> +#define OMAP4_DEF_CTRLPTV (1 << 1)
> +#define OMAP4_DEF_IRQDISABLE 0x00
> +
> +/* OMAP4 values */
> +#define OMAP4_VAL_DEBOUNCINGTIME 0x07
> +#define OMAP4_VAL_FUNCTIONALCFG 0x1E
> +
> +#define OMAP4_MASK_IRQSTATUSDISABLE 0xFFFF
> +
> +struct omap_keypad {
> +
> + struct platform_device *pdev;
> + struct omap_hwmod *oh;
> + const struct matrix_keypad_platform_data *pdata;
> +
> + void __iomem *base;
> +
> + struct input_dev *input;
> +
> + int irq;
> +
> + unsigned short *keycodes;
> + unsigned int rows;
> + unsigned int cols;
> + unsigned int debounce;
> + unsigned int row_shift;
> + unsigned char key_state[8];
> +};
> +
> +struct omap_device_pm_latency omap_keyboard_latency[] = {
> + {
> + .deactivate_func = omap_device_idle_hwmods,
> + .activate_func = omap_device_enable_hwmods,
> + .flags = OMAP_DEVICE_LATENCY_AUTO_ADJUST,
> + },
> +};
> +
> +static void __init omap_keypad_config(struct omap_keypad *keypad_data)
> +{
> + __raw_writel(OMAP4_DEF_SYSCONFIG_SOFTRST | OMAP4_DEF_SYSCONFIG_ENAWKUP,
> + keypad_data->base + OMAP4_KBD_SYSCONFIG);
> + __raw_writel(OMAP4_VAL_FUNCTIONALCFG,
> + keypad_data->base + OMAP4_KBD_CTRL);
> + __raw_writel(OMAP4_VAL_DEBOUNCINGTIME,
> + keypad_data->base + OMAP4_KBD_DEBOUNCINGTIME);
> + __raw_writel(OMAP4_DEF_IRQDISABLE,
> + keypad_data->base + OMAP4_KBD_IRQSTATUS);
> + __raw_writel(OMAP4_DEF_IRQENABLE_EVENTEN | OMAP4_DEF_IRQENABLE_LONGKEY,
> + keypad_data->base + OMAP4_KBD_IRQENABLE);
> +}
> +
> +/* Interrupt thread primary handler, called in hard interrupt context */
> +
> +static irqreturn_t omap_keypad_interrupt(int irq, void *dev_id)
> +{
> + struct omap_keypad *keypad_data = dev_id;
> +
> + /* disable interrupts */
> + __raw_writel(OMAP4_DEF_IRQDISABLE, keypad_data->base +
> + OMAP4_KBD_IRQENABLE);
> +
> + /* wake up handler thread */
> + return IRQ_WAKE_THREAD;
> +
> +}
> +
> +/* Interrupt thread handler thread */
> +
> +static irqreturn_t omap_keypad_threaded(int irq, void *dev_id)
> +{

Why is iti threaded? I fo not see anything that will sleep.

> + struct omap_keypad *keypad_data = dev_id;
> + struct input_dev *input = keypad_data->input;
> + unsigned char key_state[8];
> + int col, row, code;
> + u32 *new_state = (u32 *) key_state;
> +
> + *new_state = __raw_readl(keypad_data->base +
> + OMAP4_KBD_FULLCODE31_0);
> + *(new_state + 1) = __raw_readl(keypad_data->base +
> + OMAP4_KBD_FULLCODE63_32);
> +
> + for (col = 0; col < keypad_data->cols; col++) {
> + for (row = 0; row < keypad_data->rows; row++) {
> + code = MATRIX_SCAN_CODE(row, col,
> + keypad_data->row_shift);
> + if (code < 0) {
> + printk(KERN_INFO "Spurious key %d-%d\n",
> + col, row);
> + continue;
> + }

MATRIX_SCAN_CODE() is static data. ISR is wrong place to report
incorrect values in keymap...

> + input_report_key(input, keypad_data->keycodes[code],
> + key_state[col] & (1 << row));
> + }
> + }
> +
> + memcpy(keypad_data->key_state, &key_state,
> + sizeof(keypad_data->key_state));
> +
> + /* enable interrupts */
> + __raw_writel(OMAP4_DEF_IRQENABLE_EVENTEN | OMAP4_DEF_IRQENABLE_LONGKEY,
> + keypad_data->base + OMAP4_KBD_IRQENABLE);
> +
> + /* clear pending interrupts */
> + __raw_writel(__raw_readl(keypad_data->base + OMAP4_KBD_IRQSTATUS),
> + keypad_data->base + OMAP4_KBD_IRQSTATUS);
> +
> + /* clear pending interrupts */
> + return IRQ_HANDLED;
> +
> +}
> +
> +
> +static int __devinit omap_keypad_probe(struct platform_device *pdev)
> +{
> + struct omap_device *od;
> + struct omap_hwmod *oh;
> + struct matrix_keypad_platform_data *pdata;
> + struct input_dev *input_dev;
> + const struct matrix_keymap_data *keymap_data;
> + struct omap_keypad *keypad_data;
> +
> + unsigned int status = 0, row_shift = 0, error = 0, length = 0, id = 0;
> + unsigned short *keypad_codes;
> +
> + int hw_mod_name_len = 16;
> + char oh_name[hw_mod_name_len];
> + char *name = "omap4-keypad";
> +
> + length = snprintf(oh_name, hw_mod_name_len, "keyboard");
> + WARN(length >= hw_mod_name_len,
> + "String buffer overflow in keyboard device setup\n");
> +
> + oh = omap_hwmod_lookup(oh_name);
> + if (!oh)
> + pr_err("Could not look up %s\n", oh_name);
> +
> + pdata = kzalloc(sizeof(struct matrix_keypad_platform_data),
> + GFP_KERNEL);

Why is it allocated?

> +
> + od = omap_device_build(name, id, oh, pdata,
> + sizeof(struct matrix_keypad_platform_data),
> + omap_keyboard_latency,
> + ARRAY_SIZE(omap_keyboard_latency), 1);
> + WARN(IS_ERR(od), "Could not build omap_device for %s %s\n",
> + name, oh_name);
> +
> + /* platform data */
> + pdata = pdev->dev.platform_data;

Umm, here you are overriding pdata pointer... don't you leak memory
doing this?

> + if (!pdata) {
> + dev_err(&pdev->dev, "no platform data defined\n");
> + kfree(pdata);
> + return -EINVAL;
> + }
> +
> + /* keymap data */
> + keymap_data = pdata->keymap_data;
> + if (!keymap_data) {
> + dev_err(&pdev->dev, "no keymap data defined\n");
> + kfree(keymap_data);
> + return -EINVAL;
> + }
> +
> + /* omap keypad data */
> + row_shift = get_count_order(pdata->num_col_gpios);
> + keypad_data = kzalloc(sizeof(struct omap_keypad), GFP_KERNEL);
> + if (!keypad_data) {
> + error = -ENOMEM;
> + goto failed_free_platform;
> + }
> +
> + /* omap keypad codes */
> + keypad_codes = kzalloc((pdata->num_row_gpios << row_shift) *
> + sizeof(*keypad_codes), GFP_KERNEL);

Why is it al;loctaed separately? Can it be pickky-backed onto
keypad_data?

> + if (!keypad_codes) {
> + error = -ENOMEM;
> + goto failed_free_data;
> + }
> +
> + /* input device allocation */
> + input_dev = input_allocate_device();
> + if (!input_dev) {
> + error = -ENOMEM;
> + goto failed_free_codes;
> + }
> +
> + /* base resource */
> + keypad_data->base = oh->_rt_va;
> + if (!keypad_data->base) {

You could probably check this earlier, before allocating stuff.

> + error = -ENOMEM;
> + goto failed_free_input;
> + }
> +
> + /* irq */
> + keypad_data->irq = oh->mpu_irqs[0].irq;
> + if (keypad_data->irq < 0) {

You could probably check this earlier, before allocating stuff.

> + dev_err(&pdev->dev, "no keyboard irq assigned\n");
> + error = keypad_data->irq;
> + goto failed_free_base;
> + }
> +
> + /* threaded irq init */
> + status = request_threaded_irq(keypad_data->irq, omap_keypad_interrupt,
> + omap_keypad_threaded,
> + IRQF_TRIGGER_LOW | IRQF_ONESHOT,
> + "omap4-keypad", keypad_data);
> + if (status) {
> + dev_err(&pdev->dev, "failed to register interrupt\n");
> + error = -ENOMEM;
> + goto failed_free_irq;
> + }
> +
> + keypad_data->input = input_dev;
> + keypad_data->row_shift = row_shift;
> + keypad_data->rows = pdata->num_row_gpios;
> + keypad_data->cols = pdata->num_col_gpios;
> + keypad_data->keycodes = keypad_codes;
> +
> + input_dev->name = pdev->name;
> + input_dev->id.bustype = BUS_HOST;
> + input_dev->dev.parent = &pdev->dev;
> + input_dev->id.vendor = 0x0001;
> + input_dev->id.product = 0x0001;
> + input_dev->id.version = 0x0100;
> +
> + input_dev->keycode = keypad_codes;
> + input_dev->keycodesize = sizeof(*keypad_codes);

You also need keycodemax so that keymap can be changed from userpsace.

> +
> + matrix_keypad_build_keymap(keymap_data, row_shift,
> + input_dev->keycode, input_dev->keybit);
> +
> + __set_bit(EV_REP, input_dev->evbit);
> + __set_bit(KEY_OK, input_dev->keybit);

Why KEY_OK is set up separately?

> + __set_bit(EV_KEY, input_dev->evbit);
> +
> + input_set_capability(input_dev, EV_MSC, MSC_SCAN);

You forgot to actualy report MSC_SCAN though.

> + input_set_drvdata(input_dev, keypad_data);
> +
> + status = input_register_device(keypad_data->input);
> + if (status < 0) {
> + dev_err(&pdev->dev, "failed to register input device\n");
> + goto failed_free_device;
> + }
> +
> + omap_keypad_config(keypad_data);
> +
> + platform_set_drvdata(pdev, keypad_data);
> +
> + return 0;
> +
> +failed_free_device:
> + input_unregister_device(keypad_data->input);

input_dev = NULL;

or you will try to free it later.

> +failed_free_irq:
> + free_irq(keypad_data->irq, pdev);
> +failed_free_base:
> + keypad_data->base = NULL;
> +failed_free_input:
> + input_free_device(input_dev);
> +failed_free_codes:
> + kfree(keypad_codes);
> +failed_free_data:
> + kfree(keypad_data);
> +failed_free_platform:
> + kfree(keymap_data);
> + kfree(pdata);
> + return error;
> +}
> +
> +static int __devexit omap_keypad_remove(struct platform_device *pdev)
> +{
> + struct omap_keypad *keypad_data = platform_get_drvdata(pdev);
> +
> + input_unregister_device(keypad_data->input);
> + free_irq(keypad_data->irq, keypad_data);

Thsi should happen before unregistering input device, othersie there is
a change IRQ will arrive when input device is freed.

> + platform_set_drvdata(pdev, NULL);
> + kfree(keypad_data);
> +
> + return 0;
> +}
> +
> +static struct platform_driver omap_keypad_driver = {
> + .probe = omap_keypad_probe,
> + .remove = __devexit_p(omap_keypad_remove),
> + .driver = {
> + .name = "omap4-keypad",
> + .owner = THIS_MODULE,
> + },
> +};
> +
> +static int __init omap_keypad_init(void)
> +{
> + return platform_driver_register(&omap_keypad_driver);
> +}
> +
> +static void __exit omap_keypad_exit(void)
> +{
> + platform_driver_unregister(&omap_keypad_driver);
> +}
> +
> +module_init(omap_keypad_init);
> +module_exit(omap_keypad_exit);
> +
> +MODULE_AUTHOR("Texas Instruments");
> +MODULE_DESCRIPTION("OMAP4 Keypad Driver");
> +MODULE_LICENSE("GPL");
> +MODULE_ALIAS("platform:omap4-keypad");

--
Dmitry