284 lines
7.1 KiB
C
284 lines
7.1 KiB
C
|
/*
|
||
|
|
* Copyright (C) 2013 Daniel Tang <tangrs@tangrs.id.au>
|
||
|
|
*
|
||
|
|
* 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/input/matrix_keypad.h>
|
||
|
|
#include <linux/platform_device.h>
|
||
|
|
#include <linux/interrupt.h>
|
||
|
|
#include <linux/io.h>
|
||
|
|
#include <linux/delay.h>
|
||
|
|
#include <linux/input.h>
|
||
|
|
#include <linux/slab.h>
|
||
|
|
#include <linux/clk.h>
|
||
|
|
#include <linux/module.h>
|
||
|
|
#include <linux/of.h>
|
||
|
|
|
||
|
|
#define KEYPAD_SCAN_MODE 0x00
|
||
|
|
#define KEYPAD_CNTL 0x04
|
||
|
|
#define KEYPAD_INT 0x08
|
||
|
|
#define KEYPAD_INTMSK 0x0C
|
||
|
|
|
||
|
|
#define KEYPAD_DATA 0x10
|
||
|
|
#define KEYPAD_GPIO 0x30
|
||
|
|
|
||
|
|
#define KEYPAD_UNKNOWN_INT 0x40
|
||
|
|
#define KEYPAD_UNKNOWN_INT_STS 0x44
|
||
|
|
|
||
|
|
#define KEYPAD_BITMASK_COLS 11
|
||
|
|
#define KEYPAD_BITMASK_ROWS 8
|
||
|
|
|
||
|
|
struct nspire_keypad {
|
||
|
|
void __iomem *reg_base;
|
||
|
|
u32 int_mask;
|
||
|
|
|
||
|
|
struct input_dev *input;
|
||
|
|
struct clk *clk;
|
||
|
|
|
||
|
|
struct matrix_keymap_data *keymap;
|
||
|
|
int row_shift;
|
||
|
|
|
||
|
|
/* Maximum delay estimated assuming 33MHz APB */
|
||
|
|
u32 scan_interval; /* In microseconds (~2000us max) */
|
||
|
|
u32 row_delay; /* In microseconds (~500us max) */
|
||
|
|
|
||
|
|
u16 state[KEYPAD_BITMASK_ROWS];
|
||
|
|
|
||
|
|
bool active_low;
|
||
|
|
};
|
||
|
|
|
||
|
|
static irqreturn_t nspire_keypad_irq(int irq, void *dev_id)
|
||
|
|
{
|
||
|
|
struct nspire_keypad *keypad = dev_id;
|
||
|
|
struct input_dev *input = keypad->input;
|
||
|
|
unsigned short *keymap = input->keycode;
|
||
|
|
unsigned int code;
|
||
|
|
int row, col;
|
||
|
|
u32 int_sts;
|
||
|
|
u16 state[8];
|
||
|
|
u16 bits, changed;
|
||
|
|
|
||
|
|
int_sts = readl(keypad->reg_base + KEYPAD_INT) & keypad->int_mask;
|
||
|
|
if (!int_sts)
|
||
|
|
return IRQ_NONE;
|
||
|
|
|
||
|
|
memcpy_fromio(state, keypad->reg_base + KEYPAD_DATA, sizeof(state));
|
||
|
|
|
||
|
|
for (row = 0; row < KEYPAD_BITMASK_ROWS; row++) {
|
||
|
|
bits = state[row];
|
||
|
|
if (keypad->active_low)
|
||
|
|
bits = ~bits;
|
||
|
|
|
||
|
|
changed = bits ^ keypad->state[row];
|
||
|
|
if (!changed)
|
||
|
|
continue;
|
||
|
|
|
||
|
|
keypad->state[row] = bits;
|
||
|
|
|
||
|
|
for (col = 0; col < KEYPAD_BITMASK_COLS; col++) {
|
||
|
|
if (!(changed & (1U << col)))
|
||
|
|
continue;
|
||
|
|
|
||
|
|
code = MATRIX_SCAN_CODE(row, col, keypad->row_shift);
|
||
|
|
input_event(input, EV_MSC, MSC_SCAN, code);
|
||
|
|
input_report_key(input, keymap[code],
|
||
|
|
bits & (1U << col));
|
||
|
|
}
|
||
|
|
}
|
||
|
|
|
||
|
|
input_sync(input);
|
||
|
|
|
||
|
|
writel(0x3, keypad->reg_base + KEYPAD_INT);
|
||
|
|
|
||
|
|
return IRQ_HANDLED;
|
||
|
|
}
|
||
|
|
|
||
|
|
static int nspire_keypad_open(struct input_dev *input)
|
||
|
|
{
|
||
|
|
struct nspire_keypad *keypad = input_get_drvdata(input);
|
||
|
|
unsigned long val = 0, cycles_per_us, delay_cycles, row_delay_cycles;
|
||
|
|
int error;
|
||
|
|
|
||
|
|
error = clk_prepare_enable(keypad->clk);
|
||
|
|
if (error)
|
||
|
|
return error;
|
||
|
|
|
||
|
|
cycles_per_us = (clk_get_rate(keypad->clk) / 1000000);
|
||
|
|
if (cycles_per_us == 0)
|
||
|
|
cycles_per_us = 1;
|
||
|
|
|
||
|
|
delay_cycles = cycles_per_us * keypad->scan_interval;
|
||
|
|
WARN_ON(delay_cycles >= (1 << 16)); /* Overflow */
|
||
|
|
delay_cycles &= 0xffff;
|
||
|
|
|
||
|
|
row_delay_cycles = cycles_per_us * keypad->row_delay;
|
||
|
|
WARN_ON(row_delay_cycles >= (1 << 14)); /* Overflow */
|
||
|
|
row_delay_cycles &= 0x3fff;
|
||
|
|
|
||
|
|
val |= 3 << 0; /* Set scan mode to 3 (continuous scan) */
|
||
|
|
val |= row_delay_cycles << 2; /* Delay between scanning each row */
|
||
|
|
val |= delay_cycles << 16; /* Delay between scans */
|
||
|
|
writel(val, keypad->reg_base + KEYPAD_SCAN_MODE);
|
||
|
|
|
||
|
|
val = (KEYPAD_BITMASK_ROWS & 0xff) | (KEYPAD_BITMASK_COLS & 0xff)<<8;
|
||
|
|
writel(val, keypad->reg_base + KEYPAD_CNTL);
|
||
|
|
|
||
|
|
/* Enable interrupts */
|
||
|
|
keypad->int_mask = 1 << 1;
|
||
|
|
writel(keypad->int_mask, keypad->reg_base + KEYPAD_INTMSK);
|
||
|
|
|
||
|
|
return 0;
|
||
|
|
}
|
||
|
|
|
||
|
|
static void nspire_keypad_close(struct input_dev *input)
|
||
|
|
{
|
||
|
|
struct nspire_keypad *keypad = input_get_drvdata(input);
|
||
|
|
|
||
|
|
/* Disable interrupts */
|
||
|
|
writel(0, keypad->reg_base + KEYPAD_INTMSK);
|
||
|
|
/* Acknowledge existing interrupts */
|
||
|
|
writel(~0, keypad->reg_base + KEYPAD_INT);
|
||
|
|
|
||
|
|
clk_disable_unprepare(keypad->clk);
|
||
|
|
}
|
||
|
|
|
||
|
|
static int nspire_keypad_probe(struct platform_device *pdev)
|
||
|
|
{
|
||
|
|
const struct device_node *of_node = pdev->dev.of_node;
|
||
|
|
struct nspire_keypad *keypad;
|
||
|
|
struct input_dev *input;
|
||
|
|
struct resource *res;
|
||
|
|
int irq;
|
||
|
|
int error;
|
||
|
|
|
||
|
|
irq = platform_get_irq(pdev, 0);
|
||
|
|
if (irq < 0) {
|
||
|
|
dev_err(&pdev->dev, "failed to get keypad irq\n");
|
||
|
|
return -EINVAL;
|
||
|
|
}
|
||
|
|
|
||
|
|
keypad = devm_kzalloc(&pdev->dev, sizeof(struct nspire_keypad),
|
||
|
|
GFP_KERNEL);
|
||
|
|
if (!keypad) {
|
||
|
|
dev_err(&pdev->dev, "failed to allocate keypad memory\n");
|
||
|
|
return -ENOMEM;
|
||
|
|
}
|
||
|
|
|
||
|
|
keypad->row_shift = get_count_order(KEYPAD_BITMASK_COLS);
|
||
|
|
|
||
|
|
error = of_property_read_u32(of_node, "scan-interval",
|
||
|
|
&keypad->scan_interval);
|
||
|
|
if (error) {
|
||
|
|
dev_err(&pdev->dev, "failed to get scan-interval\n");
|
||
|
|
return error;
|
||
|
|
}
|
||
|
|
|
||
|
|
error = of_property_read_u32(of_node, "row-delay",
|
||
|
|
&keypad->row_delay);
|
||
|
|
if (error) {
|
||
|
|
dev_err(&pdev->dev, "failed to get row-delay\n");
|
||
|
|
return error;
|
||
|
|
}
|
||
|
|
|
||
|
|
keypad->active_low = of_property_read_bool(of_node, "active-low");
|
||
|
|
|
||
|
|
keypad->clk = devm_clk_get(&pdev->dev, NULL);
|
||
|
|
if (IS_ERR(keypad->clk)) {
|
||
|
|
dev_err(&pdev->dev, "unable to get clock\n");
|
||
|
|
return PTR_ERR(keypad->clk);
|
||
|
|
}
|
||
|
|
|
||
|
|
res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
|
||
|
|
keypad->reg_base = devm_ioremap_resource(&pdev->dev, res);
|
||
|
|
if (IS_ERR(keypad->reg_base))
|
||
|
|
return PTR_ERR(keypad->reg_base);
|
||
|
|
|
||
|
|
keypad->input = input = devm_input_allocate_device(&pdev->dev);
|
||
|
|
if (!input) {
|
||
|
|
dev_err(&pdev->dev, "failed to allocate input device\n");
|
||
|
|
return -ENOMEM;
|
||
|
|
}
|
||
|
|
|
||
|
|
error = clk_prepare_enable(keypad->clk);
|
||
|
|
if (error) {
|
||
|
|
dev_err(&pdev->dev, "failed to enable clock\n");
|
||
|
|
return error;
|
||
|
|
}
|
||
|
|
|
||
|
|
/* Disable interrupts */
|
||
|
|
writel(0, keypad->reg_base + KEYPAD_INTMSK);
|
||
|
|
/* Acknowledge existing interrupts */
|
||
|
|
writel(~0, keypad->reg_base + KEYPAD_INT);
|
||
|
|
|
||
|
|
/* Disable GPIO interrupts to prevent hanging on touchpad */
|
||
|
|
/* Possibly used to detect touchpad events */
|
||
|
|
writel(0, keypad->reg_base + KEYPAD_UNKNOWN_INT);
|
||
|
|
/* Acknowledge existing GPIO interrupts */
|
||
|
|
writel(~0, keypad->reg_base + KEYPAD_UNKNOWN_INT_STS);
|
||
|
|
|
||
|
|
clk_disable_unprepare(keypad->clk);
|
||
|
|
|
||
|
|
input_set_drvdata(input, keypad);
|
||
|
|
|
||
|
|
input->id.bustype = BUS_HOST;
|
||
|
|
input->name = "nspire-keypad";
|
||
|
|
input->open = nspire_keypad_open;
|
||
|
|
input->close = nspire_keypad_close;
|
||
|
|
|
||
|
|
__set_bit(EV_KEY, input->evbit);
|
||
|
|
__set_bit(EV_REP, input->evbit);
|
||
|
|
input_set_capability(input, EV_MSC, MSC_SCAN);
|
||
|
|
|
||
|
|
error = matrix_keypad_build_keymap(NULL, NULL,
|
||
|
|
KEYPAD_BITMASK_ROWS,
|
||
|
|
KEYPAD_BITMASK_COLS,
|
||
|
|
NULL, input);
|
||
|
|
if (error) {
|
||
|
|
dev_err(&pdev->dev, "building keymap failed\n");
|
||
|
|
return error;
|
||
|
|
}
|
||
|
|
|
||
|
|
error = devm_request_irq(&pdev->dev, irq, nspire_keypad_irq, 0,
|
||
|
|
"nspire_keypad", keypad);
|
||
|
|
if (error) {
|
||
|
|
dev_err(&pdev->dev, "allocate irq %d failed\n", irq);
|
||
|
|
return error;
|
||
|
|
}
|
||
|
|
|
||
|
|
error = input_register_device(input);
|
||
|
|
if (error) {
|
||
|
|
dev_err(&pdev->dev,
|
||
|
|
"unable to register input device: %d\n", error);
|
||
|
|
return error;
|
||
|
|
}
|
||
|
|
|
||
|
|
dev_dbg(&pdev->dev,
|
||
|
|
"TI-NSPIRE keypad at %pR (scan_interval=%uus, row_delay=%uus%s)\n",
|
||
|
|
res, keypad->row_delay, keypad->scan_interval,
|
||
|
|
keypad->active_low ? ", active_low" : "");
|
||
|
|
|
||
|
|
return 0;
|
||
|
|
}
|
||
|
|
|
||
|
|
static const struct of_device_id nspire_keypad_dt_match[] = {
|
||
|
|
{ .compatible = "ti,nspire-keypad" },
|
||
|
|
{ },
|
||
|
|
};
|
||
|
|
MODULE_DEVICE_TABLE(of, nspire_keypad_dt_match);
|
||
|
|
|
||
|
|
static struct platform_driver nspire_keypad_driver = {
|
||
|
|
.driver = {
|
||
|
|
.name = "nspire-keypad",
|
||
|
|
.of_match_table = nspire_keypad_dt_match,
|
||
|
|
},
|
||
|
|
.probe = nspire_keypad_probe,
|
||
|
|
};
|
||
|
|
|
||
|
|
module_platform_driver(nspire_keypad_driver);
|
||
|
|
|
||
|
|
MODULE_LICENSE("GPL");
|
||
|
|
MODULE_DESCRIPTION("TI-NSPIRE Keypad Driver");
|