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644106cdb8
A new commit in LLVM causes an error on the use of 'long double' when
'-mno-x87' is used, which the kernel does through an alias,
'-mno-80387' (see the LLVM commit below for more details around why it
does this).
drivers/power/reset/ltc2952-poweroff.c:162:28: error: expression requires 'long double' type support, but target 'x86_64-unknown-linux-gnu' does not support it
data->wde_interval = 300L * 1E6L;
^
drivers/power/reset/ltc2952-poweroff.c:162:21: error: expression requires 'long double' type support, but target 'x86_64-unknown-linux-gnu' does not support it
data->wde_interval = 300L * 1E6L;
^
drivers/power/reset/ltc2952-poweroff.c:163:41: error: expression requires 'long double' type support, but target 'x86_64-unknown-linux-gnu' does not support it
data->trigger_delay = ktime_set(2, 500L*1E6L);
^
3 errors generated.
This happens due to the use of a 'long double' literal. The 'E6' part of
'1E6L' causes the literal to be a 'double' then the 'L' suffix promotes
it to 'long double'.
There is no visible reason for floating point values in this driver, as
the values are only assigned to integer types. Use NSEC_PER_MSEC, which
is the same integer value as '1E6L', to avoid changing functionality but
fix the error.
Fixes: 6647156c00 ("power: reset: add LTC2952 poweroff driver")
Link: https://github.com/ClangBuiltLinux/linux/issues/1497
Link: a8083d42b1
Signed-off-by: Nathan Chancellor <nathan@kernel.org>
Reviewed-by: Nick Desaulniers <ndesaulniers@google.com>
Signed-off-by: Sebastian Reichel <sebastian.reichel@collabora.com>
321 lines
8.9 KiB
C
321 lines
8.9 KiB
C
// SPDX-License-Identifier: GPL-2.0-or-later
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/*
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* LTC2952 (PowerPath) driver
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*
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* Copyright (C) 2014, Xsens Technologies BV <info@xsens.com>
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* Maintainer: René Moll <linux@r-moll.nl>
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*
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* ----------------------------------------
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* - Description
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* ----------------------------------------
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*
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* This driver is to be used with an external PowerPath Controller (LTC2952).
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* Its function is to determine when a external shut down is triggered
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* and react by properly shutting down the system.
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*
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* This driver expects a device tree with a ltc2952 entry for pin mapping.
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*
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* ----------------------------------------
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* - GPIO
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* ----------------------------------------
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*
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* The following GPIOs are used:
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* - trigger (input)
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* A level change indicates the shut-down trigger. If it's state reverts
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* within the time-out defined by trigger_delay, the shut down is not
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* executed. If no pin is assigned to this input, the driver will start the
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* watchdog toggle immediately. The chip will only power off the system if
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* it is requested to do so through the kill line.
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*
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* - watchdog (output)
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* Once a shut down is triggered, the driver will toggle this signal,
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* with an internal (wde_interval) to stall the hardware shut down.
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*
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* - kill (output)
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* The last action during shut down is triggering this signalling, such
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* that the PowerPath Control will power down the hardware.
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*
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* ----------------------------------------
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* - Interrupts
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* ----------------------------------------
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*
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* The driver requires a non-shared, edge-triggered interrupt on the trigger
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* GPIO.
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*/
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#include <linux/kernel.h>
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#include <linux/init.h>
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#include <linux/interrupt.h>
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#include <linux/device.h>
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#include <linux/platform_device.h>
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#include <linux/ktime.h>
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#include <linux/slab.h>
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#include <linux/kmod.h>
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#include <linux/module.h>
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#include <linux/panic_notifier.h>
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#include <linux/mod_devicetable.h>
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#include <linux/gpio/consumer.h>
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#include <linux/reboot.h>
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#include <linux/property.h>
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struct ltc2952_poweroff {
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struct hrtimer timer_trigger;
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struct hrtimer timer_wde;
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ktime_t trigger_delay;
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ktime_t wde_interval;
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struct device *dev;
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struct gpio_desc *gpio_trigger;
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struct gpio_desc *gpio_watchdog;
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struct gpio_desc *gpio_kill;
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bool kernel_panic;
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struct notifier_block panic_notifier;
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};
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#define to_ltc2952(p, m) container_of(p, struct ltc2952_poweroff, m)
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/*
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* This global variable is only needed for pm_power_off. We should
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* remove it entirely once we don't need the global state anymore.
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*/
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static struct ltc2952_poweroff *ltc2952_data;
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/**
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* ltc2952_poweroff_timer_wde - Timer callback
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* Toggles the watchdog reset signal each wde_interval
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*
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* @timer: corresponding timer
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*
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* Returns HRTIMER_RESTART for an infinite loop which will only stop when the
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* machine actually shuts down
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*/
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static enum hrtimer_restart ltc2952_poweroff_timer_wde(struct hrtimer *timer)
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{
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int state;
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struct ltc2952_poweroff *data = to_ltc2952(timer, timer_wde);
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if (data->kernel_panic)
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return HRTIMER_NORESTART;
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state = gpiod_get_value(data->gpio_watchdog);
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gpiod_set_value(data->gpio_watchdog, !state);
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hrtimer_forward_now(timer, data->wde_interval);
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return HRTIMER_RESTART;
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}
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static void ltc2952_poweroff_start_wde(struct ltc2952_poweroff *data)
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{
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hrtimer_start(&data->timer_wde, data->wde_interval, HRTIMER_MODE_REL);
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}
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static enum hrtimer_restart
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ltc2952_poweroff_timer_trigger(struct hrtimer *timer)
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{
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struct ltc2952_poweroff *data = to_ltc2952(timer, timer_trigger);
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ltc2952_poweroff_start_wde(data);
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dev_info(data->dev, "executing shutdown\n");
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orderly_poweroff(true);
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return HRTIMER_NORESTART;
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}
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/**
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* ltc2952_poweroff_handler - Interrupt handler
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* Triggered each time the trigger signal changes state and (de)activates a
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* time-out (timer_trigger). Once the time-out is actually reached the shut
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* down is executed.
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*
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* @irq: IRQ number
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* @dev_id: pointer to the main data structure
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*/
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static irqreturn_t ltc2952_poweroff_handler(int irq, void *dev_id)
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{
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struct ltc2952_poweroff *data = dev_id;
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if (data->kernel_panic || hrtimer_active(&data->timer_wde)) {
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/* shutdown is already triggered, nothing to do any more */
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return IRQ_HANDLED;
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}
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if (gpiod_get_value(data->gpio_trigger)) {
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hrtimer_start(&data->timer_trigger, data->trigger_delay,
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HRTIMER_MODE_REL);
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} else {
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hrtimer_cancel(&data->timer_trigger);
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}
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return IRQ_HANDLED;
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}
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static void ltc2952_poweroff_kill(void)
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{
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gpiod_set_value(ltc2952_data->gpio_kill, 1);
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}
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static void ltc2952_poweroff_default(struct ltc2952_poweroff *data)
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{
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data->wde_interval = 300L * NSEC_PER_MSEC;
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data->trigger_delay = ktime_set(2, 500L * NSEC_PER_MSEC);
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hrtimer_init(&data->timer_trigger, CLOCK_MONOTONIC, HRTIMER_MODE_REL);
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data->timer_trigger.function = ltc2952_poweroff_timer_trigger;
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hrtimer_init(&data->timer_wde, CLOCK_MONOTONIC, HRTIMER_MODE_REL);
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data->timer_wde.function = ltc2952_poweroff_timer_wde;
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}
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static int ltc2952_poweroff_init(struct platform_device *pdev)
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{
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int ret;
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u32 trigger_delay_ms;
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struct ltc2952_poweroff *data = platform_get_drvdata(pdev);
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ltc2952_poweroff_default(data);
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if (!device_property_read_u32(&pdev->dev, "trigger-delay-ms",
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&trigger_delay_ms)) {
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data->trigger_delay = ktime_set(trigger_delay_ms / MSEC_PER_SEC,
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(trigger_delay_ms % MSEC_PER_SEC) * NSEC_PER_MSEC);
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}
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data->gpio_watchdog = devm_gpiod_get(&pdev->dev, "watchdog",
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GPIOD_OUT_LOW);
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if (IS_ERR(data->gpio_watchdog)) {
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ret = PTR_ERR(data->gpio_watchdog);
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dev_err(&pdev->dev, "unable to claim gpio \"watchdog\"\n");
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return ret;
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}
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data->gpio_kill = devm_gpiod_get(&pdev->dev, "kill", GPIOD_OUT_LOW);
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if (IS_ERR(data->gpio_kill)) {
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ret = PTR_ERR(data->gpio_kill);
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dev_err(&pdev->dev, "unable to claim gpio \"kill\"\n");
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return ret;
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}
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data->gpio_trigger = devm_gpiod_get_optional(&pdev->dev, "trigger",
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GPIOD_IN);
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if (IS_ERR(data->gpio_trigger)) {
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/*
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* It's not a problem if the trigger gpio isn't available, but
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* it is worth a warning if its use was defined in the device
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* tree.
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*/
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dev_err(&pdev->dev, "unable to claim gpio \"trigger\"\n");
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data->gpio_trigger = NULL;
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}
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if (devm_request_irq(&pdev->dev, gpiod_to_irq(data->gpio_trigger),
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ltc2952_poweroff_handler,
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(IRQF_TRIGGER_FALLING | IRQF_TRIGGER_RISING),
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"ltc2952-poweroff",
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data)) {
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/*
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* Some things may have happened:
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* - No trigger input was defined
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* - Claiming the GPIO failed
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* - We could not map to an IRQ
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* - We couldn't register an interrupt handler
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*
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* None of these really are problems, but all of them
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* disqualify the push button from controlling the power.
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*
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* It is therefore important to note that if the ltc2952
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* detects a button press for long enough, it will still start
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* its own powerdown window and cut the power on us if we don't
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* start the watchdog trigger.
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*/
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if (data->gpio_trigger) {
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dev_warn(&pdev->dev,
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"unable to configure the trigger interrupt\n");
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devm_gpiod_put(&pdev->dev, data->gpio_trigger);
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data->gpio_trigger = NULL;
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}
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dev_info(&pdev->dev,
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"power down trigger input will not be used\n");
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ltc2952_poweroff_start_wde(data);
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}
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return 0;
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}
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static int ltc2952_poweroff_notify_panic(struct notifier_block *nb,
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unsigned long code, void *unused)
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{
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struct ltc2952_poweroff *data = to_ltc2952(nb, panic_notifier);
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data->kernel_panic = true;
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return NOTIFY_DONE;
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}
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static int ltc2952_poweroff_probe(struct platform_device *pdev)
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{
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int ret;
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struct ltc2952_poweroff *data;
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if (pm_power_off) {
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dev_err(&pdev->dev, "pm_power_off already registered");
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return -EBUSY;
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}
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data = devm_kzalloc(&pdev->dev, sizeof(*data), GFP_KERNEL);
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if (!data)
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return -ENOMEM;
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data->dev = &pdev->dev;
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platform_set_drvdata(pdev, data);
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ret = ltc2952_poweroff_init(pdev);
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if (ret)
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return ret;
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/* TODO: remove ltc2952_data */
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ltc2952_data = data;
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pm_power_off = ltc2952_poweroff_kill;
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data->panic_notifier.notifier_call = ltc2952_poweroff_notify_panic;
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atomic_notifier_chain_register(&panic_notifier_list,
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&data->panic_notifier);
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dev_info(&pdev->dev, "probe successful\n");
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return 0;
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}
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static int ltc2952_poweroff_remove(struct platform_device *pdev)
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{
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struct ltc2952_poweroff *data = platform_get_drvdata(pdev);
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pm_power_off = NULL;
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hrtimer_cancel(&data->timer_trigger);
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hrtimer_cancel(&data->timer_wde);
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atomic_notifier_chain_unregister(&panic_notifier_list,
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&data->panic_notifier);
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return 0;
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}
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static const struct of_device_id of_ltc2952_poweroff_match[] = {
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{ .compatible = "lltc,ltc2952"},
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{},
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};
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MODULE_DEVICE_TABLE(of, of_ltc2952_poweroff_match);
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static struct platform_driver ltc2952_poweroff_driver = {
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.probe = ltc2952_poweroff_probe,
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.remove = ltc2952_poweroff_remove,
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.driver = {
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.name = "ltc2952-poweroff",
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.of_match_table = of_ltc2952_poweroff_match,
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},
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};
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module_platform_driver(ltc2952_poweroff_driver);
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MODULE_AUTHOR("René Moll <rene.moll@xsens.com>");
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MODULE_DESCRIPTION("LTC PowerPath power-off driver");
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MODULE_LICENSE("GPL v2");
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