/*
* SPEAr Keyboard Driver
* Based on omap-keypad driver
*
* Copyright (C) 2010 ST Microelectronics
* Rajeev Kumar <rajeevkumar.linux@gmail.com>
*
* This file is licensed under the terms of the GNU General Public
* License version 2. This program is licensed "as is" without any
* warranty of any kind, whether express or implied.
*/
#include <linux/clk.h>
#include <linux/errno.h>
#include <linux/interrupt.h>
#include <linux/input.h>
#include <linux/io.h>
#include <linux/irq.h>
#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/of.h>
#include <linux/platform_device.h>
#include <linux/pm_wakeup.h>
#include <linux/slab.h>
#include <linux/types.h>
#include <linux/platform_data/keyboard-spear.h>
/* Keyboard Registers */
#define MODE_CTL_REG 0x00
#define STATUS_REG 0x0C
#define DATA_REG 0x10
#define INTR_MASK 0x54
/* Register Values */
#define NUM_ROWS 16
#define NUM_COLS 16
#define MODE_CTL_PCLK_FREQ_SHIFT 9
#define MODE_CTL_PCLK_FREQ_MSK 0x7F
#define MODE_CTL_KEYBOARD (0x2 << 0)
#define MODE_CTL_SCAN_RATE_10 (0x0 << 2)
#define MODE_CTL_SCAN_RATE_20 (0x1 << 2)
#define MODE_CTL_SCAN_RATE_40 (0x2 << 2)
#define MODE_CTL_SCAN_RATE_80 (0x3 << 2)
#define MODE_CTL_KEYNUM_SHIFT 6
#define MODE_CTL_START_SCAN (0x1 << 8)
#define STATUS_DATA_AVAIL (0x1 << 1)
#define DATA_ROW_MASK 0xF0
#define DATA_COLUMN_MASK 0x0F
#define ROW_SHIFT 4
struct spear_kbd {
struct input_dev *input;
void __iomem *io_base;
struct clk *clk;
unsigned int irq;
unsigned int mode;
unsigned int suspended_rate;
unsigned short last_key;
unsigned short keycodes[NUM_ROWS * NUM_COLS];
bool rep;
bool irq_wake_enabled;
u32 mode_ctl_reg;
};
static irqreturn_t spear_kbd_interrupt(int irq, void *dev_id)
{
struct spear_kbd *kbd = dev_id;
struct input_dev *input = kbd->input;
unsigned int key;
u32 sts, val;
sts = readl_relaxed(kbd->io_base + STATUS_REG);
if (!(sts & STATUS_DATA_AVAIL))
return IRQ_NONE;
if (kbd->last_key != KEY_RESERVED) {
input_report_key(input, kbd->last_key, 0);
kbd->last_key = KEY_RESERVED;
}
/* following reads active (row, col) pair */
val = readl_relaxed(kbd->io_base + DATA_REG) &
(DATA_ROW_MASK | DATA_COLUMN_MASK);
key = kbd->keycodes[val];
input_event(input, EV_MSC, MSC_SCAN, val);
input_report_key(input, key, 1);
input_sync(input);
kbd->last_key = key;
/* clear interrupt */
writel_relaxed(0, kbd->io_base + STATUS_REG);
return IRQ_HANDLED;
}
static int spear_kbd_open(struct input_dev *dev)
{
struct spear_kbd *kbd = input_get_drvdata(dev);
int error;
u32 val;
kbd->last_key = KEY_RESERVED;
error = clk_enable(kbd->clk);
if (error)
return error;
/* keyboard rate to be programmed is input clock (in MHz) - 1 */
val = clk_get_rate(kbd->clk) / 1000000 - 1;
val = (val & MODE_CTL_PCLK_FREQ_MSK) << MODE_CTL_PCLK_FREQ_SHIFT;
/* program keyboard */
val = MODE_CTL_SCAN_RATE_80 | MODE_CTL_KEYBOARD | val |
(kbd->mode << MODE_CTL_KEYNUM_SHIFT);
writel_relaxed(val, kbd->io_base + MODE_CTL_REG);
writel_relaxed(1, kbd->io_base + STATUS_REG);
/* start key scan */
val = readl_relaxed(kbd->io_base + MODE_CTL_REG);
val |= MODE_CTL_START_SCAN;
writel_relaxed(val, kbd->io_base + MODE_CTL_REG);
return 0;
}
static void spear_kbd_close(struct input_dev *dev)
{
struct spear_kbd *kbd = input_get_drvdata(dev);
u32 val;
/* stop key scan */
val = readl_relaxed(kbd->io_base + MODE_CTL_REG);
val &= ~MODE_CTL_START_SCAN;
writel_relaxed(val, kbd->io_base + MODE_CTL_REG);
clk_disable(kbd->clk);
kbd->last_key = KEY_RESERVED;
}
#ifdef [31mCONFIG_OF[0m
static int spear_kbd_parse_dt(struct platform_device *pdev,
struct spear_kbd *kbd)
{
struct device_node *np = pdev->dev.of_node;
int error;
u32 val, suspended_rate;
if (!np) {
dev_err(&pdev->dev, "Missing DT data\n");
return -EINVAL;
}
if (of_property_read_bool(np, "autorepeat"))
kbd->rep = true;
if (of_property_read_u32(np, "suspended_rate", &suspended_rate))
kbd->suspended_rate = suspended_rate;
error = of_property_read_u32(np, "st,mode", &val);
if (error) {
dev_err(&pdev->dev, "DT: Invalid or missing mode\n");
return error;
}
kbd->mode = val;
return 0;
}
#else
static inline int spear_kbd_parse_dt(struct platform_device *pdev,
struct spear_kbd *kbd)
{
return -ENOSYS;
}
#endif
static int spear_kbd_probe(struct platform_device *pdev)
{
struct kbd_platform_data *pdata = dev_get_platdata(&pdev->dev);
const struct matrix_keymap_data *keymap = pdata ? pdata->keymap : NULL;
struct spear_kbd *kbd;
struct input_dev *input_dev;
struct resource *res;
int irq;
int error;
irq = platform_get_irq(pdev, 0);
if (irq < 0)
return irq;
kbd = devm_kzalloc(&pdev->dev, sizeof(*kbd), GFP_KERNEL);
if (!kbd) {
dev_err(&pdev->dev, "not enough memory for driver data\n");
return -ENOMEM;
}
input_dev = devm_input_allocate_device(&pdev->dev);
if (!input_dev) {
dev_err(&pdev->dev, "unable to allocate input device\n");
return -ENOMEM;
}
kbd->input = input_dev;
kbd->irq = irq;
if (!pdata) {
error = spear_kbd_parse_dt(pdev, kbd);
if (error)
return error;
} else {
kbd->mode = pdata->mode;
kbd->rep = pdata->rep;
kbd->suspended_rate = pdata->suspended_rate;
}
res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
kbd->io_base = devm_ioremap_resource(&pdev->dev, res);
if (IS_ERR(kbd->io_base))
return PTR_ERR(kbd->io_base);
kbd->clk = devm_clk_get(&pdev->dev, NULL);
if (IS_ERR(kbd->clk))
return PTR_ERR(kbd->clk);
input_dev->name = "Spear Keyboard";
input_dev->phys = "keyboard/input0";
input_dev->id.bustype = BUS_HOST;
input_dev->id.vendor = 0x0001;
input_dev->id.product = 0x0001;
input_dev->id.version = 0x0100;
input_dev->open = spear_kbd_open;
input_dev->close = spear_kbd_close;
error = matrix_keypad_build_keymap(keymap, NULL, NUM_ROWS, NUM_COLS,
kbd->keycodes, input_dev);
if (error) {
dev_err(&pdev->dev, "Failed to build keymap\n");
return error;
}
if (kbd->rep)
__set_bit(EV_REP, input_dev->evbit);
input_set_capability(input_dev, EV_MSC, MSC_SCAN);
input_set_drvdata(input_dev, kbd);
error = devm_request_irq(&pdev->dev, irq, spear_kbd_interrupt, 0,
"keyboard", kbd);
if (error) {
dev_err(&pdev->dev, "request_irq failed\n");
return error;
}
error = clk_prepare(kbd->clk);
if (error)
return error;
error = input_register_device(input_dev);
if (error) {
dev_err(&pdev->dev, "Unable to register keyboard device\n");
clk_unprepare(kbd->clk);
return error;
}
device_init_wakeup(&pdev->dev, 1);
platform_set_drvdata(pdev, kbd);
return 0;
}
static int spear_kbd_remove(struct platform_device *pdev)
{
struct spear_kbd *kbd = platform_get_drvdata(pdev);
input_unregister_device(kbd->input);
clk_unprepare(kbd->clk);
return 0;
}
static int __maybe_unused spear_kbd_suspend(struct device *dev)
{
struct platform_device *pdev = to_platform_device(dev);
struct spear_kbd *kbd = platform_get_drvdata(pdev);
struct input_dev *input_dev = kbd->input;
unsigned int rate = 0, mode_ctl_reg, val;
mutex_lock(&input_dev->mutex);
/* explicitly enable clock as we may program device */
clk_enable(kbd->clk);
mode_ctl_reg = readl_relaxed(kbd->io_base + MODE_CTL_REG);
if (device_may_wakeup(&pdev->dev)) {
if (!enable_irq_wake(kbd->irq))
kbd->irq_wake_enabled = true;
/*
* reprogram the keyboard operating frequency as on some
* platform it may change during system suspended
*/
if (kbd->suspended_rate)
rate = kbd->suspended_rate / 1000000 - 1;
else
rate = clk_get_rate(kbd->clk) / 1000000 - 1;
val = mode_ctl_reg &
~(MODE_CTL_PCLK_FREQ_MSK << MODE_CTL_PCLK_FREQ_SHIFT);
val |= (rate & MODE_CTL_PCLK_FREQ_MSK)
<< MODE_CTL_PCLK_FREQ_SHIFT;
writel_relaxed(val, kbd->io_base + MODE_CTL_REG);
} else {
if (input_dev->users) {
writel_relaxed(mode_ctl_reg & ~MODE_CTL_START_SCAN,
kbd->io_base + MODE_CTL_REG);
clk_disable(kbd->clk);
}
}
/* store current configuration */
if (input_dev->users)
kbd->mode_ctl_reg = mode_ctl_reg;
/* restore previous clk state */
clk_disable(kbd->clk);
mutex_unlock(&input_dev->mutex);
return 0;
}
static int __maybe_unused spear_kbd_resume(struct device *dev)
{
struct platform_device *pdev = to_platform_device(dev);
struct spear_kbd *kbd = platform_get_drvdata(pdev);
struct input_dev *input_dev = kbd->input;
mutex_lock(&input_dev->mutex);
if (device_may_wakeup(&pdev->dev)) {
if (kbd->irq_wake_enabled) {
kbd->irq_wake_enabled = false;
disable_irq_wake(kbd->irq);
}
} else {
if (input_dev->users)
clk_enable(kbd->clk);
}
/* restore current configuration */
if (input_dev->users)
writel_relaxed(kbd->mode_ctl_reg, kbd->io_base + MODE_CTL_REG);
mutex_unlock(&input_dev->mutex);
return 0;
}
static SIMPLE_DEV_PM_OPS(spear_kbd_pm_ops, spear_kbd_suspend, spear_kbd_resume);
#ifdef [31mCONFIG_OF[0m
static const struct of_device_id spear_kbd_id_table[] = {
{ .compatible = "st,spear300-kbd" },
{}
};
MODULE_DEVICE_TABLE(of, spear_kbd_id_table);
#endif
static struct platform_driver spear_kbd_driver = {
.probe = spear_kbd_probe,
.remove = spear_kbd_remove,
.driver = {
.name = "keyboard",
.pm = &spear_kbd_pm_ops,
.of_match_table = of_match_ptr(spear_kbd_id_table),
},
};
module_platform_driver(spear_kbd_driver);
MODULE_AUTHOR("Rajeev Kumar");
MODULE_DESCRIPTION("SPEAr Keyboard Driver");
MODULE_LICENSE("GPL");