408 lines
11 KiB
C
408 lines
11 KiB
C
// SPDX-License-Identifier: GPL-2.0-or-later
|
|
/*
|
|
* Copyright (C) 2013 STMicroelectronics Limited
|
|
* Author: Srinivas Kandagatla <srinivas.kandagatla@st.com>
|
|
*/
|
|
#include <linux/kernel.h>
|
|
#include <linux/clk.h>
|
|
#include <linux/interrupt.h>
|
|
#include <linux/module.h>
|
|
#include <linux/of.h>
|
|
#include <linux/platform_device.h>
|
|
#include <linux/reset.h>
|
|
#include <media/rc-core.h>
|
|
#include <linux/pinctrl/consumer.h>
|
|
#include <linux/pm_wakeirq.h>
|
|
|
|
struct st_rc_device {
|
|
struct device *dev;
|
|
int irq;
|
|
int irq_wake;
|
|
struct clk *sys_clock;
|
|
void __iomem *base; /* Register base address */
|
|
void __iomem *rx_base;/* RX Register base address */
|
|
struct rc_dev *rdev;
|
|
bool overclocking;
|
|
int sample_mult;
|
|
int sample_div;
|
|
bool rxuhfmode;
|
|
struct reset_control *rstc;
|
|
};
|
|
|
|
/* Registers */
|
|
#define IRB_SAMPLE_RATE_COMM 0x64 /* sample freq divisor*/
|
|
#define IRB_CLOCK_SEL 0x70 /* clock select */
|
|
#define IRB_CLOCK_SEL_STATUS 0x74 /* clock status */
|
|
/* IRB IR/UHF receiver registers */
|
|
#define IRB_RX_ON 0x40 /* pulse time capture */
|
|
#define IRB_RX_SYS 0X44 /* sym period capture */
|
|
#define IRB_RX_INT_EN 0x48 /* IRQ enable (R/W) */
|
|
#define IRB_RX_INT_STATUS 0x4c /* IRQ status (R/W) */
|
|
#define IRB_RX_EN 0x50 /* Receive enable */
|
|
#define IRB_MAX_SYM_PERIOD 0x54 /* max sym value */
|
|
#define IRB_RX_INT_CLEAR 0x58 /* overrun status */
|
|
#define IRB_RX_STATUS 0x6c /* receive status */
|
|
#define IRB_RX_NOISE_SUPPR 0x5c /* noise suppression */
|
|
#define IRB_RX_POLARITY_INV 0x68 /* polarity inverter */
|
|
|
|
/*
|
|
* IRQ set: Enable full FIFO 1 -> bit 3;
|
|
* Enable overrun IRQ 1 -> bit 2;
|
|
* Enable last symbol IRQ 1 -> bit 1:
|
|
* Enable RX interrupt 1 -> bit 0;
|
|
*/
|
|
#define IRB_RX_INTS 0x0f
|
|
#define IRB_RX_OVERRUN_INT 0x04
|
|
/* maximum symbol period (microsecs),timeout to detect end of symbol train */
|
|
#define MAX_SYMB_TIME 0x5000
|
|
#define IRB_SAMPLE_FREQ 10000000
|
|
#define IRB_FIFO_NOT_EMPTY 0xff00
|
|
#define IRB_OVERFLOW 0x4
|
|
#define IRB_TIMEOUT 0xffff
|
|
#define IR_ST_NAME "st-rc"
|
|
|
|
static void st_rc_send_lirc_timeout(struct rc_dev *rdev)
|
|
{
|
|
struct ir_raw_event ev = { .timeout = true, .duration = rdev->timeout };
|
|
ir_raw_event_store(rdev, &ev);
|
|
}
|
|
|
|
/*
|
|
* RX graphical example to better understand the difference between ST IR block
|
|
* output and standard definition used by LIRC (and most of the world!)
|
|
*
|
|
* mark mark
|
|
* |-IRB_RX_ON-| |-IRB_RX_ON-|
|
|
* ___ ___ ___ ___ ___ ___ _
|
|
* | | | | | | | | | | | | |
|
|
* | | | | | | space 0 | | | | | | space 1 |
|
|
* _____| |__| |__| |____________________________| |__| |__| |_____________|
|
|
*
|
|
* |--------------- IRB_RX_SYS -------------|------ IRB_RX_SYS -------|
|
|
*
|
|
* |------------- encoding bit 0 -----------|---- encoding bit 1 -----|
|
|
*
|
|
* ST hardware returns mark (IRB_RX_ON) and total symbol time (IRB_RX_SYS), so
|
|
* convert to standard mark/space we have to calculate space=(IRB_RX_SYS-mark)
|
|
* The mark time represents the amount of time the carrier (usually 36-40kHz)
|
|
* is detected.The above examples shows Pulse Width Modulation encoding where
|
|
* bit 0 is represented by space>mark.
|
|
*/
|
|
|
|
static irqreturn_t st_rc_rx_interrupt(int irq, void *data)
|
|
{
|
|
unsigned long timeout;
|
|
unsigned int symbol, mark = 0;
|
|
struct st_rc_device *dev = data;
|
|
int last_symbol = 0;
|
|
u32 status, int_status;
|
|
struct ir_raw_event ev = {};
|
|
|
|
if (dev->irq_wake)
|
|
pm_wakeup_event(dev->dev, 0);
|
|
|
|
/* FIXME: is 10ms good enough ? */
|
|
timeout = jiffies + msecs_to_jiffies(10);
|
|
do {
|
|
status = readl(dev->rx_base + IRB_RX_STATUS);
|
|
if (!(status & (IRB_FIFO_NOT_EMPTY | IRB_OVERFLOW)))
|
|
break;
|
|
|
|
int_status = readl(dev->rx_base + IRB_RX_INT_STATUS);
|
|
if (unlikely(int_status & IRB_RX_OVERRUN_INT)) {
|
|
/* discard the entire collection in case of errors! */
|
|
ir_raw_event_reset(dev->rdev);
|
|
dev_info(dev->dev, "IR RX overrun\n");
|
|
writel(IRB_RX_OVERRUN_INT,
|
|
dev->rx_base + IRB_RX_INT_CLEAR);
|
|
continue;
|
|
}
|
|
|
|
symbol = readl(dev->rx_base + IRB_RX_SYS);
|
|
mark = readl(dev->rx_base + IRB_RX_ON);
|
|
|
|
if (symbol == IRB_TIMEOUT)
|
|
last_symbol = 1;
|
|
|
|
/* Ignore any noise */
|
|
if ((mark > 2) && (symbol > 1)) {
|
|
symbol -= mark;
|
|
if (dev->overclocking) { /* adjustments to timings */
|
|
symbol *= dev->sample_mult;
|
|
symbol /= dev->sample_div;
|
|
mark *= dev->sample_mult;
|
|
mark /= dev->sample_div;
|
|
}
|
|
|
|
ev.duration = US_TO_NS(mark);
|
|
ev.pulse = true;
|
|
ir_raw_event_store(dev->rdev, &ev);
|
|
|
|
if (!last_symbol) {
|
|
ev.duration = US_TO_NS(symbol);
|
|
ev.pulse = false;
|
|
ir_raw_event_store(dev->rdev, &ev);
|
|
} else {
|
|
st_rc_send_lirc_timeout(dev->rdev);
|
|
}
|
|
|
|
}
|
|
last_symbol = 0;
|
|
} while (time_is_after_jiffies(timeout));
|
|
|
|
writel(IRB_RX_INTS, dev->rx_base + IRB_RX_INT_CLEAR);
|
|
|
|
/* Empty software fifo */
|
|
ir_raw_event_handle(dev->rdev);
|
|
return IRQ_HANDLED;
|
|
}
|
|
|
|
static void st_rc_hardware_init(struct st_rc_device *dev)
|
|
{
|
|
int baseclock, freqdiff;
|
|
unsigned int rx_max_symbol_per = MAX_SYMB_TIME;
|
|
unsigned int rx_sampling_freq_div;
|
|
|
|
/* Enable the IP */
|
|
reset_control_deassert(dev->rstc);
|
|
|
|
clk_prepare_enable(dev->sys_clock);
|
|
baseclock = clk_get_rate(dev->sys_clock);
|
|
|
|
/* IRB input pins are inverted internally from high to low. */
|
|
writel(1, dev->rx_base + IRB_RX_POLARITY_INV);
|
|
|
|
rx_sampling_freq_div = baseclock / IRB_SAMPLE_FREQ;
|
|
writel(rx_sampling_freq_div, dev->base + IRB_SAMPLE_RATE_COMM);
|
|
|
|
freqdiff = baseclock - (rx_sampling_freq_div * IRB_SAMPLE_FREQ);
|
|
if (freqdiff) { /* over clocking, workout the adjustment factors */
|
|
dev->overclocking = true;
|
|
dev->sample_mult = 1000;
|
|
dev->sample_div = baseclock / (10000 * rx_sampling_freq_div);
|
|
rx_max_symbol_per = (rx_max_symbol_per * 1000)/dev->sample_div;
|
|
}
|
|
|
|
writel(rx_max_symbol_per, dev->rx_base + IRB_MAX_SYM_PERIOD);
|
|
}
|
|
|
|
static int st_rc_remove(struct platform_device *pdev)
|
|
{
|
|
struct st_rc_device *rc_dev = platform_get_drvdata(pdev);
|
|
|
|
dev_pm_clear_wake_irq(&pdev->dev);
|
|
device_init_wakeup(&pdev->dev, false);
|
|
clk_disable_unprepare(rc_dev->sys_clock);
|
|
rc_unregister_device(rc_dev->rdev);
|
|
return 0;
|
|
}
|
|
|
|
static int st_rc_open(struct rc_dev *rdev)
|
|
{
|
|
struct st_rc_device *dev = rdev->priv;
|
|
unsigned long flags;
|
|
local_irq_save(flags);
|
|
/* enable interrupts and receiver */
|
|
writel(IRB_RX_INTS, dev->rx_base + IRB_RX_INT_EN);
|
|
writel(0x01, dev->rx_base + IRB_RX_EN);
|
|
local_irq_restore(flags);
|
|
|
|
return 0;
|
|
}
|
|
|
|
static void st_rc_close(struct rc_dev *rdev)
|
|
{
|
|
struct st_rc_device *dev = rdev->priv;
|
|
/* disable interrupts and receiver */
|
|
writel(0x00, dev->rx_base + IRB_RX_EN);
|
|
writel(0x00, dev->rx_base + IRB_RX_INT_EN);
|
|
}
|
|
|
|
static int st_rc_probe(struct platform_device *pdev)
|
|
{
|
|
int ret = -EINVAL;
|
|
struct rc_dev *rdev;
|
|
struct device *dev = &pdev->dev;
|
|
struct resource *res;
|
|
struct st_rc_device *rc_dev;
|
|
struct device_node *np = pdev->dev.of_node;
|
|
const char *rx_mode;
|
|
|
|
rc_dev = devm_kzalloc(dev, sizeof(struct st_rc_device), GFP_KERNEL);
|
|
|
|
if (!rc_dev)
|
|
return -ENOMEM;
|
|
|
|
rdev = rc_allocate_device(RC_DRIVER_IR_RAW);
|
|
|
|
if (!rdev)
|
|
return -ENOMEM;
|
|
|
|
if (np && !of_property_read_string(np, "rx-mode", &rx_mode)) {
|
|
|
|
if (!strcmp(rx_mode, "uhf")) {
|
|
rc_dev->rxuhfmode = true;
|
|
} else if (!strcmp(rx_mode, "infrared")) {
|
|
rc_dev->rxuhfmode = false;
|
|
} else {
|
|
dev_err(dev, "Unsupported rx mode [%s]\n", rx_mode);
|
|
goto err;
|
|
}
|
|
|
|
} else {
|
|
goto err;
|
|
}
|
|
|
|
rc_dev->sys_clock = devm_clk_get(dev, NULL);
|
|
if (IS_ERR(rc_dev->sys_clock)) {
|
|
dev_err(dev, "System clock not found\n");
|
|
ret = PTR_ERR(rc_dev->sys_clock);
|
|
goto err;
|
|
}
|
|
|
|
rc_dev->irq = platform_get_irq(pdev, 0);
|
|
if (rc_dev->irq < 0) {
|
|
ret = rc_dev->irq;
|
|
goto err;
|
|
}
|
|
|
|
res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
|
|
|
|
rc_dev->base = devm_ioremap_resource(dev, res);
|
|
if (IS_ERR(rc_dev->base)) {
|
|
ret = PTR_ERR(rc_dev->base);
|
|
goto err;
|
|
}
|
|
|
|
if (rc_dev->rxuhfmode)
|
|
rc_dev->rx_base = rc_dev->base + 0x40;
|
|
else
|
|
rc_dev->rx_base = rc_dev->base;
|
|
|
|
rc_dev->rstc = reset_control_get_optional_exclusive(dev, NULL);
|
|
if (IS_ERR(rc_dev->rstc)) {
|
|
ret = PTR_ERR(rc_dev->rstc);
|
|
goto err;
|
|
}
|
|
|
|
rc_dev->dev = dev;
|
|
platform_set_drvdata(pdev, rc_dev);
|
|
st_rc_hardware_init(rc_dev);
|
|
|
|
rdev->allowed_protocols = RC_PROTO_BIT_ALL_IR_DECODER;
|
|
/* rx sampling rate is 10Mhz */
|
|
rdev->rx_resolution = 100;
|
|
rdev->timeout = US_TO_NS(MAX_SYMB_TIME);
|
|
rdev->priv = rc_dev;
|
|
rdev->open = st_rc_open;
|
|
rdev->close = st_rc_close;
|
|
rdev->driver_name = IR_ST_NAME;
|
|
rdev->map_name = RC_MAP_EMPTY;
|
|
rdev->device_name = "ST Remote Control Receiver";
|
|
|
|
ret = rc_register_device(rdev);
|
|
if (ret < 0)
|
|
goto clkerr;
|
|
|
|
rc_dev->rdev = rdev;
|
|
if (devm_request_irq(dev, rc_dev->irq, st_rc_rx_interrupt,
|
|
0, IR_ST_NAME, rc_dev) < 0) {
|
|
dev_err(dev, "IRQ %d register failed\n", rc_dev->irq);
|
|
ret = -EINVAL;
|
|
goto rcerr;
|
|
}
|
|
|
|
/* enable wake via this device */
|
|
device_init_wakeup(dev, true);
|
|
dev_pm_set_wake_irq(dev, rc_dev->irq);
|
|
|
|
/*
|
|
* for LIRC_MODE_MODE2 or LIRC_MODE_PULSE or LIRC_MODE_RAW
|
|
* lircd expects a long space first before a signal train to sync.
|
|
*/
|
|
st_rc_send_lirc_timeout(rdev);
|
|
|
|
dev_info(dev, "setup in %s mode\n", rc_dev->rxuhfmode ? "UHF" : "IR");
|
|
|
|
return ret;
|
|
rcerr:
|
|
rc_unregister_device(rdev);
|
|
rdev = NULL;
|
|
clkerr:
|
|
clk_disable_unprepare(rc_dev->sys_clock);
|
|
err:
|
|
rc_free_device(rdev);
|
|
dev_err(dev, "Unable to register device (%d)\n", ret);
|
|
return ret;
|
|
}
|
|
|
|
#ifdef CONFIG_PM_SLEEP
|
|
static int st_rc_suspend(struct device *dev)
|
|
{
|
|
struct st_rc_device *rc_dev = dev_get_drvdata(dev);
|
|
|
|
if (device_may_wakeup(dev)) {
|
|
if (!enable_irq_wake(rc_dev->irq))
|
|
rc_dev->irq_wake = 1;
|
|
else
|
|
return -EINVAL;
|
|
} else {
|
|
pinctrl_pm_select_sleep_state(dev);
|
|
writel(0x00, rc_dev->rx_base + IRB_RX_EN);
|
|
writel(0x00, rc_dev->rx_base + IRB_RX_INT_EN);
|
|
clk_disable_unprepare(rc_dev->sys_clock);
|
|
reset_control_assert(rc_dev->rstc);
|
|
}
|
|
|
|
return 0;
|
|
}
|
|
|
|
static int st_rc_resume(struct device *dev)
|
|
{
|
|
struct st_rc_device *rc_dev = dev_get_drvdata(dev);
|
|
struct rc_dev *rdev = rc_dev->rdev;
|
|
|
|
if (rc_dev->irq_wake) {
|
|
disable_irq_wake(rc_dev->irq);
|
|
rc_dev->irq_wake = 0;
|
|
} else {
|
|
pinctrl_pm_select_default_state(dev);
|
|
st_rc_hardware_init(rc_dev);
|
|
if (rdev->users) {
|
|
writel(IRB_RX_INTS, rc_dev->rx_base + IRB_RX_INT_EN);
|
|
writel(0x01, rc_dev->rx_base + IRB_RX_EN);
|
|
}
|
|
}
|
|
|
|
return 0;
|
|
}
|
|
|
|
#endif
|
|
|
|
static SIMPLE_DEV_PM_OPS(st_rc_pm_ops, st_rc_suspend, st_rc_resume);
|
|
|
|
#ifdef CONFIG_OF
|
|
static const struct of_device_id st_rc_match[] = {
|
|
{ .compatible = "st,comms-irb", },
|
|
{},
|
|
};
|
|
|
|
MODULE_DEVICE_TABLE(of, st_rc_match);
|
|
#endif
|
|
|
|
static struct platform_driver st_rc_driver = {
|
|
.driver = {
|
|
.name = IR_ST_NAME,
|
|
.of_match_table = of_match_ptr(st_rc_match),
|
|
.pm = &st_rc_pm_ops,
|
|
},
|
|
.probe = st_rc_probe,
|
|
.remove = st_rc_remove,
|
|
};
|
|
|
|
module_platform_driver(st_rc_driver);
|
|
|
|
MODULE_DESCRIPTION("RC Transceiver driver for STMicroelectronics platforms");
|
|
MODULE_AUTHOR("STMicroelectronics (R&D) Ltd");
|
|
MODULE_LICENSE("GPL");
|