Files
android_kernel_xiaomi_sm8450/drivers/input/keyboard/sh_keysc.c
Magnus Damm 2dfb9a85ec Input: sh_keysc - switch to threaded IRQ handler
Update the KEYSC driver to make use of threaded IRQs with IRQF_ONESHOT
to improve interrupt latency. The driver is using udelay() in the ISR
to make sure the hardware has stabilized. Without using interrupt threads
this delay may affect the latency of the rest of the system.

Also pass dev_name() as string for /proc/interrupts.

Signed-off-by: Magnus Damm <damm@opensource.se>
Signed-off-by: Dmitry Torokhov <dtor@mail.ru>
2011-04-28 09:36:48 -07:00

357 lines
8.2 KiB
C

/*
* SuperH KEYSC Keypad Driver
*
* Copyright (C) 2008 Magnus Damm
*
* Based on gpio_keys.c, Copyright 2005 Phil Blundell
*
* 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/kernel.h>
#include <linux/module.h>
#include <linux/init.h>
#include <linux/interrupt.h>
#include <linux/irq.h>
#include <linux/delay.h>
#include <linux/platform_device.h>
#include <linux/input.h>
#include <linux/input/sh_keysc.h>
#include <linux/bitmap.h>
#include <linux/pm_runtime.h>
#include <linux/io.h>
#include <linux/slab.h>
static const struct {
unsigned char kymd, keyout, keyin;
} sh_keysc_mode[] = {
[SH_KEYSC_MODE_1] = { 0, 6, 5 },
[SH_KEYSC_MODE_2] = { 1, 5, 6 },
[SH_KEYSC_MODE_3] = { 2, 4, 7 },
[SH_KEYSC_MODE_4] = { 3, 6, 6 },
[SH_KEYSC_MODE_5] = { 4, 6, 7 },
[SH_KEYSC_MODE_6] = { 5, 7, 7 },
};
struct sh_keysc_priv {
void __iomem *iomem_base;
DECLARE_BITMAP(last_keys, SH_KEYSC_MAXKEYS);
struct input_dev *input;
struct sh_keysc_info pdata;
};
#define KYCR1 0
#define KYCR2 1
#define KYINDR 2
#define KYOUTDR 3
#define KYCR2_IRQ_LEVEL 0x10
#define KYCR2_IRQ_DISABLED 0x00
static unsigned long sh_keysc_read(struct sh_keysc_priv *p, int reg_nr)
{
return ioread16(p->iomem_base + (reg_nr << 2));
}
static void sh_keysc_write(struct sh_keysc_priv *p, int reg_nr,
unsigned long value)
{
iowrite16(value, p->iomem_base + (reg_nr << 2));
}
static void sh_keysc_level_mode(struct sh_keysc_priv *p,
unsigned long keys_set)
{
struct sh_keysc_info *pdata = &p->pdata;
sh_keysc_write(p, KYOUTDR, 0);
sh_keysc_write(p, KYCR2, KYCR2_IRQ_LEVEL | (keys_set << 8));
if (pdata->kycr2_delay)
udelay(pdata->kycr2_delay);
}
static void sh_keysc_map_dbg(struct device *dev, unsigned long *map,
const char *str)
{
int k;
for (k = 0; k < BITS_TO_LONGS(SH_KEYSC_MAXKEYS); k++)
dev_dbg(dev, "%s[%d] 0x%lx\n", str, k, map[k]);
}
static irqreturn_t sh_keysc_isr(int irq, void *dev_id)
{
struct platform_device *pdev = dev_id;
struct sh_keysc_priv *priv = platform_get_drvdata(pdev);
struct sh_keysc_info *pdata = &priv->pdata;
int keyout_nr = sh_keysc_mode[pdata->mode].keyout;
int keyin_nr = sh_keysc_mode[pdata->mode].keyin;
DECLARE_BITMAP(keys, SH_KEYSC_MAXKEYS);
DECLARE_BITMAP(keys0, SH_KEYSC_MAXKEYS);
DECLARE_BITMAP(keys1, SH_KEYSC_MAXKEYS);
unsigned char keyin_set, tmp;
int i, k, n;
dev_dbg(&pdev->dev, "isr!\n");
bitmap_fill(keys1, SH_KEYSC_MAXKEYS);
bitmap_zero(keys0, SH_KEYSC_MAXKEYS);
do {
bitmap_zero(keys, SH_KEYSC_MAXKEYS);
keyin_set = 0;
sh_keysc_write(priv, KYCR2, KYCR2_IRQ_DISABLED);
for (i = 0; i < keyout_nr; i++) {
n = keyin_nr * i;
/* drive one KEYOUT pin low, read KEYIN pins */
sh_keysc_write(priv, KYOUTDR, 0xffff ^ (3 << (i * 2)));
udelay(pdata->delay);
tmp = sh_keysc_read(priv, KYINDR);
/* set bit if key press has been detected */
for (k = 0; k < keyin_nr; k++) {
if (tmp & (1 << k))
__set_bit(n + k, keys);
}
/* keep track of which KEYIN bits that have been set */
keyin_set |= tmp ^ ((1 << keyin_nr) - 1);
}
sh_keysc_level_mode(priv, keyin_set);
bitmap_complement(keys, keys, SH_KEYSC_MAXKEYS);
bitmap_and(keys1, keys1, keys, SH_KEYSC_MAXKEYS);
bitmap_or(keys0, keys0, keys, SH_KEYSC_MAXKEYS);
sh_keysc_map_dbg(&pdev->dev, keys, "keys");
} while (sh_keysc_read(priv, KYCR2) & 0x01);
sh_keysc_map_dbg(&pdev->dev, priv->last_keys, "last_keys");
sh_keysc_map_dbg(&pdev->dev, keys0, "keys0");
sh_keysc_map_dbg(&pdev->dev, keys1, "keys1");
for (i = 0; i < SH_KEYSC_MAXKEYS; i++) {
k = pdata->keycodes[i];
if (!k)
continue;
if (test_bit(i, keys0) == test_bit(i, priv->last_keys))
continue;
if (test_bit(i, keys1) || test_bit(i, keys0)) {
input_event(priv->input, EV_KEY, k, 1);
__set_bit(i, priv->last_keys);
}
if (!test_bit(i, keys1)) {
input_event(priv->input, EV_KEY, k, 0);
__clear_bit(i, priv->last_keys);
}
}
input_sync(priv->input);
return IRQ_HANDLED;
}
static int __devinit sh_keysc_probe(struct platform_device *pdev)
{
struct sh_keysc_priv *priv;
struct sh_keysc_info *pdata;
struct resource *res;
struct input_dev *input;
int i;
int irq, error;
if (!pdev->dev.platform_data) {
dev_err(&pdev->dev, "no platform data defined\n");
error = -EINVAL;
goto err0;
}
error = -ENXIO;
res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
if (res == NULL) {
dev_err(&pdev->dev, "failed to get I/O memory\n");
goto err0;
}
irq = platform_get_irq(pdev, 0);
if (irq < 0) {
dev_err(&pdev->dev, "failed to get irq\n");
goto err0;
}
priv = kzalloc(sizeof(*priv), GFP_KERNEL);
if (priv == NULL) {
dev_err(&pdev->dev, "failed to allocate driver data\n");
error = -ENOMEM;
goto err0;
}
platform_set_drvdata(pdev, priv);
memcpy(&priv->pdata, pdev->dev.platform_data, sizeof(priv->pdata));
pdata = &priv->pdata;
priv->iomem_base = ioremap_nocache(res->start, resource_size(res));
if (priv->iomem_base == NULL) {
dev_err(&pdev->dev, "failed to remap I/O memory\n");
error = -ENXIO;
goto err1;
}
priv->input = input_allocate_device();
if (!priv->input) {
dev_err(&pdev->dev, "failed to allocate input device\n");
error = -ENOMEM;
goto err2;
}
input = priv->input;
input->evbit[0] = BIT_MASK(EV_KEY);
input->name = pdev->name;
input->phys = "sh-keysc-keys/input0";
input->dev.parent = &pdev->dev;
input->id.bustype = BUS_HOST;
input->id.vendor = 0x0001;
input->id.product = 0x0001;
input->id.version = 0x0100;
input->keycode = pdata->keycodes;
input->keycodesize = sizeof(pdata->keycodes[0]);
input->keycodemax = ARRAY_SIZE(pdata->keycodes);
error = request_threaded_irq(irq, NULL, sh_keysc_isr, IRQF_ONESHOT,
dev_name(&pdev->dev), pdev);
if (error) {
dev_err(&pdev->dev, "failed to request IRQ\n");
goto err3;
}
for (i = 0; i < SH_KEYSC_MAXKEYS; i++)
__set_bit(pdata->keycodes[i], input->keybit);
__clear_bit(KEY_RESERVED, input->keybit);
error = input_register_device(input);
if (error) {
dev_err(&pdev->dev, "failed to register input device\n");
goto err4;
}
pm_runtime_enable(&pdev->dev);
pm_runtime_get_sync(&pdev->dev);
sh_keysc_write(priv, KYCR1, (sh_keysc_mode[pdata->mode].kymd << 8) |
pdata->scan_timing);
sh_keysc_level_mode(priv, 0);
device_init_wakeup(&pdev->dev, 1);
return 0;
err4:
free_irq(irq, pdev);
err3:
input_free_device(input);
err2:
iounmap(priv->iomem_base);
err1:
platform_set_drvdata(pdev, NULL);
kfree(priv);
err0:
return error;
}
static int __devexit sh_keysc_remove(struct platform_device *pdev)
{
struct sh_keysc_priv *priv = platform_get_drvdata(pdev);
sh_keysc_write(priv, KYCR2, KYCR2_IRQ_DISABLED);
input_unregister_device(priv->input);
free_irq(platform_get_irq(pdev, 0), pdev);
iounmap(priv->iomem_base);
pm_runtime_put_sync(&pdev->dev);
pm_runtime_disable(&pdev->dev);
platform_set_drvdata(pdev, NULL);
kfree(priv);
return 0;
}
static int sh_keysc_suspend(struct device *dev)
{
struct platform_device *pdev = to_platform_device(dev);
struct sh_keysc_priv *priv = platform_get_drvdata(pdev);
int irq = platform_get_irq(pdev, 0);
unsigned short value;
value = sh_keysc_read(priv, KYCR1);
if (device_may_wakeup(dev)) {
sh_keysc_write(priv, KYCR1, value | 0x80);
enable_irq_wake(irq);
} else {
sh_keysc_write(priv, KYCR1, value & ~0x80);
pm_runtime_put_sync(dev);
}
return 0;
}
static int sh_keysc_resume(struct device *dev)
{
struct platform_device *pdev = to_platform_device(dev);
int irq = platform_get_irq(pdev, 0);
if (device_may_wakeup(dev))
disable_irq_wake(irq);
else
pm_runtime_get_sync(dev);
return 0;
}
static const struct dev_pm_ops sh_keysc_dev_pm_ops = {
.suspend = sh_keysc_suspend,
.resume = sh_keysc_resume,
};
struct platform_driver sh_keysc_device_driver = {
.probe = sh_keysc_probe,
.remove = __devexit_p(sh_keysc_remove),
.driver = {
.name = "sh_keysc",
.pm = &sh_keysc_dev_pm_ops,
}
};
static int __init sh_keysc_init(void)
{
return platform_driver_register(&sh_keysc_device_driver);
}
static void __exit sh_keysc_exit(void)
{
platform_driver_unregister(&sh_keysc_device_driver);
}
module_init(sh_keysc_init);
module_exit(sh_keysc_exit);
MODULE_AUTHOR("Magnus Damm");
MODULE_DESCRIPTION("SuperH KEYSC Keypad Driver");
MODULE_LICENSE("GPL");