linux/drivers/media/rc/meson-ir.c

254 lines
6.6 KiB
C

/*
* Driver for Amlogic Meson IR remote receiver
*
* Copyright (C) 2014 Beniamino Galvani <b.galvani@gmail.com>
*
* 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.
*
* You should have received a copy of the GNU General Public License
* along with this program. If not, see <http://www.gnu.org/licenses/>.
*/
#include <linux/device.h>
#include <linux/err.h>
#include <linux/interrupt.h>
#include <linux/io.h>
#include <linux/module.h>
#include <linux/of_platform.h>
#include <linux/platform_device.h>
#include <linux/spinlock.h>
#include <linux/bitfield.h>
#include <media/rc-core.h>
#define DRIVER_NAME "meson-ir"
/* valid on all Meson platforms */
#define IR_DEC_LDR_ACTIVE 0x00
#define IR_DEC_LDR_IDLE 0x04
#define IR_DEC_LDR_REPEAT 0x08
#define IR_DEC_BIT_0 0x0c
#define IR_DEC_REG0 0x10
#define IR_DEC_FRAME 0x14
#define IR_DEC_STATUS 0x18
#define IR_DEC_REG1 0x1c
/* only available on Meson 8b and newer */
#define IR_DEC_REG2 0x20
#define REG0_RATE_MASK GENMASK(11, 0)
#define DECODE_MODE_NEC 0x0
#define DECODE_MODE_RAW 0x2
/* Meson 6b uses REG1 to configure the mode */
#define REG1_MODE_MASK GENMASK(8, 7)
#define REG1_MODE_SHIFT 7
/* Meson 8b / GXBB use REG2 to configure the mode */
#define REG2_MODE_MASK GENMASK(3, 0)
#define REG2_MODE_SHIFT 0
#define REG1_TIME_IV_MASK GENMASK(28, 16)
#define REG1_IRQSEL_MASK GENMASK(3, 2)
#define REG1_IRQSEL_NEC_MODE 0
#define REG1_IRQSEL_RISE_FALL 1
#define REG1_IRQSEL_FALL 2
#define REG1_IRQSEL_RISE 3
#define REG1_RESET BIT(0)
#define REG1_ENABLE BIT(15)
#define STATUS_IR_DEC_IN BIT(8)
#define MESON_TRATE 10 /* us */
struct meson_ir {
void __iomem *reg;
struct rc_dev *rc;
spinlock_t lock;
};
static void meson_ir_set_mask(struct meson_ir *ir, unsigned int reg,
u32 mask, u32 value)
{
u32 data;
data = readl(ir->reg + reg);
data &= ~mask;
data |= (value & mask);
writel(data, ir->reg + reg);
}
static irqreturn_t meson_ir_irq(int irqno, void *dev_id)
{
struct meson_ir *ir = dev_id;
u32 duration, status;
struct ir_raw_event rawir = {};
spin_lock(&ir->lock);
duration = readl_relaxed(ir->reg + IR_DEC_REG1);
duration = FIELD_GET(REG1_TIME_IV_MASK, duration);
rawir.duration = US_TO_NS(duration * MESON_TRATE);
status = readl_relaxed(ir->reg + IR_DEC_STATUS);
rawir.pulse = !!(status & STATUS_IR_DEC_IN);
ir_raw_event_store_with_timeout(ir->rc, &rawir);
spin_unlock(&ir->lock);
return IRQ_HANDLED;
}
static int meson_ir_probe(struct platform_device *pdev)
{
struct device *dev = &pdev->dev;
struct device_node *node = dev->of_node;
struct resource *res;
const char *map_name;
struct meson_ir *ir;
int irq, ret;
ir = devm_kzalloc(dev, sizeof(struct meson_ir), GFP_KERNEL);
if (!ir)
return -ENOMEM;
res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
ir->reg = devm_ioremap_resource(dev, res);
if (IS_ERR(ir->reg)) {
dev_err(dev, "failed to map registers\n");
return PTR_ERR(ir->reg);
}
irq = platform_get_irq(pdev, 0);
if (irq < 0) {
dev_err(dev, "no irq resource\n");
return irq;
}
ir->rc = devm_rc_allocate_device(dev, RC_DRIVER_IR_RAW);
if (!ir->rc) {
dev_err(dev, "failed to allocate rc device\n");
return -ENOMEM;
}
ir->rc->priv = ir;
ir->rc->device_name = DRIVER_NAME;
ir->rc->input_phys = DRIVER_NAME "/input0";
ir->rc->input_id.bustype = BUS_HOST;
map_name = of_get_property(node, "linux,rc-map-name", NULL);
ir->rc->map_name = map_name ? map_name : RC_MAP_EMPTY;
ir->rc->allowed_protocols = RC_PROTO_BIT_ALL_IR_DECODER;
ir->rc->rx_resolution = US_TO_NS(MESON_TRATE);
ir->rc->min_timeout = 1;
ir->rc->timeout = IR_DEFAULT_TIMEOUT;
ir->rc->max_timeout = 10 * IR_DEFAULT_TIMEOUT;
ir->rc->driver_name = DRIVER_NAME;
spin_lock_init(&ir->lock);
platform_set_drvdata(pdev, ir);
ret = devm_rc_register_device(dev, ir->rc);
if (ret) {
dev_err(dev, "failed to register rc device\n");
return ret;
}
ret = devm_request_irq(dev, irq, meson_ir_irq, 0, NULL, ir);
if (ret) {
dev_err(dev, "failed to request irq\n");
return ret;
}
/* Reset the decoder */
meson_ir_set_mask(ir, IR_DEC_REG1, REG1_RESET, REG1_RESET);
meson_ir_set_mask(ir, IR_DEC_REG1, REG1_RESET, 0);
/* Set general operation mode (= raw/software decoding) */
if (of_device_is_compatible(node, "amlogic,meson6-ir"))
meson_ir_set_mask(ir, IR_DEC_REG1, REG1_MODE_MASK,
FIELD_PREP(REG1_MODE_MASK, DECODE_MODE_RAW));
else
meson_ir_set_mask(ir, IR_DEC_REG2, REG2_MODE_MASK,
FIELD_PREP(REG2_MODE_MASK, DECODE_MODE_RAW));
/* Set rate */
meson_ir_set_mask(ir, IR_DEC_REG0, REG0_RATE_MASK, MESON_TRATE - 1);
/* IRQ on rising and falling edges */
meson_ir_set_mask(ir, IR_DEC_REG1, REG1_IRQSEL_MASK,
FIELD_PREP(REG1_IRQSEL_MASK, REG1_IRQSEL_RISE_FALL));
/* Enable the decoder */
meson_ir_set_mask(ir, IR_DEC_REG1, REG1_ENABLE, REG1_ENABLE);
dev_info(dev, "receiver initialized\n");
return 0;
}
static int meson_ir_remove(struct platform_device *pdev)
{
struct meson_ir *ir = platform_get_drvdata(pdev);
unsigned long flags;
/* Disable the decoder */
spin_lock_irqsave(&ir->lock, flags);
meson_ir_set_mask(ir, IR_DEC_REG1, REG1_ENABLE, 0);
spin_unlock_irqrestore(&ir->lock, flags);
return 0;
}
static void meson_ir_shutdown(struct platform_device *pdev)
{
struct device *dev = &pdev->dev;
struct device_node *node = dev->of_node;
struct meson_ir *ir = platform_get_drvdata(pdev);
unsigned long flags;
spin_lock_irqsave(&ir->lock, flags);
/*
* Set operation mode to NEC/hardware decoding to give
* bootloader a chance to power the system back on
*/
if (of_device_is_compatible(node, "amlogic,meson6-ir"))
meson_ir_set_mask(ir, IR_DEC_REG1, REG1_MODE_MASK,
DECODE_MODE_NEC << REG1_MODE_SHIFT);
else
meson_ir_set_mask(ir, IR_DEC_REG2, REG2_MODE_MASK,
DECODE_MODE_NEC << REG2_MODE_SHIFT);
/* Set rate to default value */
meson_ir_set_mask(ir, IR_DEC_REG0, REG0_RATE_MASK, 0x13);
spin_unlock_irqrestore(&ir->lock, flags);
}
static const struct of_device_id meson_ir_match[] = {
{ .compatible = "amlogic,meson6-ir" },
{ .compatible = "amlogic,meson8b-ir" },
{ .compatible = "amlogic,meson-gxbb-ir" },
{ },
};
MODULE_DEVICE_TABLE(of, meson_ir_match);
static struct platform_driver meson_ir_driver = {
.probe = meson_ir_probe,
.remove = meson_ir_remove,
.shutdown = meson_ir_shutdown,
.driver = {
.name = DRIVER_NAME,
.of_match_table = meson_ir_match,
},
};
module_platform_driver(meson_ir_driver);
MODULE_DESCRIPTION("Amlogic Meson IR remote receiver driver");
MODULE_AUTHOR("Beniamino Galvani <b.galvani@gmail.com>");
MODULE_LICENSE("GPL v2");