Em Thu, 29 Aug 2013 10:11:56 +0100
Sean Young <sean@xxxxxxxx> escreveu:
> On Wed, Aug 28, 2013 at 04:33:50PM +0100, Srinivas KANDAGATLA wrote:
> > From: Srinivas Kandagatla <srinivas.kandagatla@xxxxxx>
> >
> > This patch adds support to ST RC driver, which is basically a IR/UHF
> > receiver and transmitter. This IP (IRB) is common across all the ST
> > parts for settop box platforms. IRB is embedded in ST COMMS IP block.
> > It supports both Rx & Tx functionality.
> >
> > In this driver adds only Rx functionality via LIRC codec.
> >
> > Signed-off-by: Srinivas Kandagatla <srinivas.kandagatla@xxxxxx>
> > ---
> > Hi Chehab,
> >
> > This is a very simple rc driver for IRB controller found in STi ARM CA9 SOCs.
> > STi ARM SOC support went in 3.11 recently.
> > This driver is a raw driver which feeds data to lirc codec for the user lircd
> > to decode the keys.
> >
> > This patch is based on git://linuxtv.org/media_tree.git master branch.
> >
> > Changes since v1:
> > - Device tree bindings cleaned up as suggested by Mark and Pawel
> > - use ir_raw_event_reset under overflow conditions as suggested by Sean.
> > - call ir_raw_event_handle in interrupt handler as suggested by Sean.
> > - correct allowed_protos flag with RC_BIT_ types as suggested by Sean.
> > - timeout and rx resolution added as suggested by Sean.
>
> Acked-by: Sean Young <sean@xxxxxxxx>
>
> Note minor nitpicks below.
> >
> > Thanks,
> > srini
> >
> > Documentation/devicetree/bindings/media/st-rc.txt | 24 ++
> > drivers/media/rc/Kconfig | 10 +
> > drivers/media/rc/Makefile | 1 +
> > drivers/media/rc/st_rc.c | 392 +++++++++++++++++++++
> > 4 files changed, 427 insertions(+), 0 deletions(-)
> > create mode 100644 Documentation/devicetree/bindings/media/st-rc.txt
> > create mode 100644 drivers/media/rc/st_rc.c
> >
> > diff --git a/Documentation/devicetree/bindings/media/st-rc.txt b/Documentation/devicetree/bindings/media/st-rc.txt
> > new file mode 100644
> > index 0000000..20fe264
> > --- /dev/null
> > +++ b/Documentation/devicetree/bindings/media/st-rc.txt
> > @@ -0,0 +1,24 @@
> > +Device-Tree bindings for ST IRB IP
> > +
> > +Required properties:
> > + - compatible: should be "st,comms-irb".
> > + - reg: base physical address of the controller and length of memory
> > + mapped region.
> > + - interrupts: interrupt number to the cpu. The interrupt specifier
> > + format depends on the interrupt controller parent.
> > +
> > +Optional properties:
> > + - rx-mode: can be "infrared" or "uhf".
> > + - tx-mode: should be "infrared".
> > + - pinctrl-names, pinctrl-0: the pincontrol settings to configure
> > + muxing properly for IRB pins.
> > + - clocks : phandle of clock.
> > +
> > +Example node:
> > +
> > + rc: rc@fe518000 {
> > + compatible = "st,comms-irb";
> > + reg = <0xfe518000 0x234>;
> > + interrupts = <0 203 0>;
> > + rx-mode = "infrared";
> > + };
> > diff --git a/drivers/media/rc/Kconfig b/drivers/media/rc/Kconfig
> > index 11e84bc..bf301ed 100644
> > --- a/drivers/media/rc/Kconfig
> > +++ b/drivers/media/rc/Kconfig
> > @@ -322,4 +322,14 @@ config IR_GPIO_CIR
> > To compile this driver as a module, choose M here: the module will
> > be called gpio-ir-recv.
> >
> > +config RC_ST
> > + tristate "ST remote control receiver"
> > + depends on ARCH_STI && LIRC && OF
>
> Minor nitpick, this should not depend on LIRC, it depends on RC_CORE.
>
> > + help
> > + Say Y here if you want support for ST remote control driver
> > + which allows both IR and UHF RX.
> > + The driver passes raw pluse and space information to the LIRC decoder.
> > +
> > + If you're not sure, select N here.
> > +
> > endif #RC_DEVICES
> > diff --git a/drivers/media/rc/Makefile b/drivers/media/rc/Makefile
> > index 56bacf0..f4eb32c 100644
> > --- a/drivers/media/rc/Makefile
> > +++ b/drivers/media/rc/Makefile
> > @@ -30,3 +30,4 @@ obj-$(CONFIG_RC_LOOPBACK) += rc-loopback.o
> > obj-$(CONFIG_IR_GPIO_CIR) += gpio-ir-recv.o
> > obj-$(CONFIG_IR_IGUANA) += iguanair.o
> > obj-$(CONFIG_IR_TTUSBIR) += ttusbir.o
> > +obj-$(CONFIG_RC_ST) += st_rc.o
> > diff --git a/drivers/media/rc/st_rc.c b/drivers/media/rc/st_rc.c
> > new file mode 100644
> > index 0000000..5caa6c5
> > --- /dev/null
> > +++ b/drivers/media/rc/st_rc.c
> > @@ -0,0 +1,392 @@
> > +/*
> > + * Copyright (C) 2013 STMicroelectronics Limited
> > + * Author: Srinivas Kandagatla <srinivas.kandagatla@xxxxxx>
> > + *
> > + * This program is free software; you can redistribute it and/or modify
> > + * it under the terms of the GNU General Public License as published by
> > + * the Free Software Foundation; either version 2 of the License, or
> > + * (at your option) any later version.
> > + */
> > +#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 <media/rc-core.h>
> > +#include <linux/pinctrl/consumer.h>
> > +
> > +struct st_rc_device {
> > + struct device *dev;
> > + int irq;
> > + int irq_wake;
> > + struct clk *sys_clock;
> > + void *base; /* Register base address */
> > + void *rx_base;/* RX Register base address */
> > + struct rc_dev *rdev;
> > + bool overclocking;
> > + int sample_mult;
> > + int sample_div;
> > + bool rxuhfmode;
> > +};
> > +
> > +/* 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 enablei */
> > +#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)
> > +{
> > + DEFINE_IR_RAW_EVENT(ev);
> > + ev.timeout = true;
> > + 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 int symbol, mark = 0;
> > + struct st_rc_device *dev = data;
> > + int last_symbol = 0;
> > + u32 status;
> > + DEFINE_IR_RAW_EVENT(ev);
> > +
> > + if (dev->irq_wake)
> > + pm_wakeup_event(dev->dev, 0);
> > +
> > + status = readl(dev->rx_base + IRB_RX_STATUS);
> > +
> > + while (status & (IRB_FIFO_NOT_EMPTY | IRB_OVERFLOW)) {
> > + u32 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;
> > + status = readl(dev->rx_base + IRB_RX_STATUS);
> > + }
> > +
> > + 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;
> > +
> > + 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);
> > + 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);
> > + rdev = rc_allocate_device();
> > +
> > + if (!rc_dev || !rdev)
> > + return -ENOMEM;
>
> If one fails and the other succeeds you have a leak.
>
> > +
> > + 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 clkerr;
> > + }
> > +
> > + ret = -ENODEV;
> > + res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
> > + if (!res)
> > + goto clkerr;
> > +
> > + rc_dev->base = devm_ioremap_resource(dev, res);
> > + if (IS_ERR(rc_dev->base))
> > + goto clkerr;
> > +
> > + if (rc_dev->rxuhfmode)
> > + rc_dev->rx_base = rc_dev->base + 0x40;
> > + else
> > + rc_dev->rx_base = rc_dev->base;
> > +
> > + rc_dev->dev = dev;
> > + platform_set_drvdata(pdev, rc_dev);
> > + st_rc_hardware_init(rc_dev);
> > +
> > + rdev->driver_type = RC_DRIVER_IR_RAW;
> > + rdev->allowed_protos = RC_BIT_ALL;
> > + /* 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_LIRC;
> > + rdev->input_name = "ST Remote Control Receiver";
> > +
> > + /* enable wake via this device */
> > + device_set_wakeup_capable(dev, true);
> > + device_set_wakeup_enable(dev, true);
> > +
> > + 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,
> > + IRQF_NO_SUSPEND, IR_ST_NAME, rc_dev) < 0) {
> > + dev_err(dev, "IRQ %d register failed\n", rc_dev->irq);
> > + ret = -EINVAL;
> > + goto rcerr;
> > + }
> > +
> > + /**
> > + * 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
> > +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);
> > + }
> > +
> > + 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;
> > +}
> > +
> > +static SIMPLE_DEV_PM_OPS(st_rc_pm_ops, st_rc_suspend, st_rc_resume);
> > +#endif
> > +
> > +#ifdef CONFIG_OF
>
> Since this depends on OF it will always be defined.
It is probably good to keep this and to remove the OF dependency at
Kconfig, allowing this driver to be compiled and used without OF,
it this could make sense on some setup.
>
> > +static 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,
> > + .owner = THIS_MODULE,
> > + .of_match_table = of_match_ptr(st_rc_match),
> > +#ifdef CONFIG_PM
> > + .pm = &st_rc_pm_ops,
> > +#endif
> > + },
> > + .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");
> > --
> > 1.7.6.5
Except for the few points that Sean commented, the patch seems ok on my eyes.
Regards,
Mauro
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