linuxdebug/drivers/input/keyboard/pxa930_rotary.c

196 lines
4.3 KiB
C

// SPDX-License-Identifier: GPL-2.0-only
/*
* Driver for the enhanced rotary controller on pxa930 and pxa935
*/
#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/interrupt.h>
#include <linux/input.h>
#include <linux/platform_device.h>
#include <linux/io.h>
#include <linux/slab.h>
#include <linux/platform_data/keyboard-pxa930_rotary.h>
#define SBCR (0x04)
#define ERCR (0x0c)
#define SBCR_ERSB (1 << 5)
struct pxa930_rotary {
struct input_dev *input_dev;
void __iomem *mmio_base;
int last_ercr;
struct pxa930_rotary_platform_data *pdata;
};
static void clear_sbcr(struct pxa930_rotary *r)
{
uint32_t sbcr = __raw_readl(r->mmio_base + SBCR);
__raw_writel(sbcr | SBCR_ERSB, r->mmio_base + SBCR);
__raw_writel(sbcr & ~SBCR_ERSB, r->mmio_base + SBCR);
}
static irqreturn_t rotary_irq(int irq, void *dev_id)
{
struct pxa930_rotary *r = dev_id;
struct pxa930_rotary_platform_data *pdata = r->pdata;
int ercr, delta, key;
ercr = __raw_readl(r->mmio_base + ERCR) & 0xf;
clear_sbcr(r);
delta = ercr - r->last_ercr;
if (delta == 0)
return IRQ_HANDLED;
r->last_ercr = ercr;
if (pdata->up_key && pdata->down_key) {
key = (delta > 0) ? pdata->up_key : pdata->down_key;
input_report_key(r->input_dev, key, 1);
input_sync(r->input_dev);
input_report_key(r->input_dev, key, 0);
} else
input_report_rel(r->input_dev, pdata->rel_code, delta);
input_sync(r->input_dev);
return IRQ_HANDLED;
}
static int pxa930_rotary_open(struct input_dev *dev)
{
struct pxa930_rotary *r = input_get_drvdata(dev);
clear_sbcr(r);
return 0;
}
static void pxa930_rotary_close(struct input_dev *dev)
{
struct pxa930_rotary *r = input_get_drvdata(dev);
clear_sbcr(r);
}
static int pxa930_rotary_probe(struct platform_device *pdev)
{
struct pxa930_rotary_platform_data *pdata =
dev_get_platdata(&pdev->dev);
struct pxa930_rotary *r;
struct input_dev *input_dev;
struct resource *res;
int irq;
int err;
irq = platform_get_irq(pdev, 0);
if (irq < 0)
return -ENXIO;
res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
if (!res) {
dev_err(&pdev->dev, "no I/O memory defined\n");
return -ENXIO;
}
if (!pdata) {
dev_err(&pdev->dev, "no platform data defined\n");
return -EINVAL;
}
r = kzalloc(sizeof(struct pxa930_rotary), GFP_KERNEL);
if (!r)
return -ENOMEM;
r->mmio_base = ioremap(res->start, resource_size(res));
if (r->mmio_base == NULL) {
dev_err(&pdev->dev, "failed to remap IO memory\n");
err = -ENXIO;
goto failed_free;
}
r->pdata = pdata;
platform_set_drvdata(pdev, r);
/* allocate and register the input device */
input_dev = input_allocate_device();
if (!input_dev) {
dev_err(&pdev->dev, "failed to allocate input device\n");
err = -ENOMEM;
goto failed_free_io;
}
input_dev->name = pdev->name;
input_dev->id.bustype = BUS_HOST;
input_dev->open = pxa930_rotary_open;
input_dev->close = pxa930_rotary_close;
input_dev->dev.parent = &pdev->dev;
if (pdata->up_key && pdata->down_key) {
__set_bit(pdata->up_key, input_dev->keybit);
__set_bit(pdata->down_key, input_dev->keybit);
__set_bit(EV_KEY, input_dev->evbit);
} else {
__set_bit(pdata->rel_code, input_dev->relbit);
__set_bit(EV_REL, input_dev->evbit);
}
r->input_dev = input_dev;
input_set_drvdata(input_dev, r);
err = request_irq(irq, rotary_irq, 0,
"enhanced rotary", r);
if (err) {
dev_err(&pdev->dev, "failed to request IRQ\n");
goto failed_free_input;
}
err = input_register_device(input_dev);
if (err) {
dev_err(&pdev->dev, "failed to register input device\n");
goto failed_free_irq;
}
return 0;
failed_free_irq:
free_irq(irq, r);
failed_free_input:
input_free_device(input_dev);
failed_free_io:
iounmap(r->mmio_base);
failed_free:
kfree(r);
return err;
}
static int pxa930_rotary_remove(struct platform_device *pdev)
{
struct pxa930_rotary *r = platform_get_drvdata(pdev);
free_irq(platform_get_irq(pdev, 0), r);
input_unregister_device(r->input_dev);
iounmap(r->mmio_base);
kfree(r);
return 0;
}
static struct platform_driver pxa930_rotary_driver = {
.driver = {
.name = "pxa930-rotary",
},
.probe = pxa930_rotary_probe,
.remove = pxa930_rotary_remove,
};
module_platform_driver(pxa930_rotary_driver);
MODULE_LICENSE("GPL");
MODULE_DESCRIPTION("Driver for PXA93x Enhanced Rotary Controller");
MODULE_AUTHOR("Yao Yong <yaoyong@marvell.com>");