/* * Watchdog driver for Ricoh RN5T618 PMIC * * Copyright (C) 2014 Beniamino Galvani * * 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 . */ #include #include #include #include #include #define DRIVER_NAME "rn5t618-wdt" static bool nowayout = WATCHDOG_NOWAYOUT; static unsigned int timeout; module_param(timeout, uint, 0); MODULE_PARM_DESC(timeout, "Initial watchdog timeout in seconds"); module_param(nowayout, bool, 0); MODULE_PARM_DESC(nowayout, "Watchdog cannot be stopped once started (default=" __MODULE_STRING(WATCHDOG_NOWAYOUT) ")"); struct rn5t618_wdt { struct watchdog_device wdt_dev; struct rn5t618 *rn5t618; }; /* * This array encodes the values of WDOGTIM field for the supported * watchdog expiration times. If the watchdog is not accessed before * the timer expiration, the PMU generates an interrupt and if the CPU * doesn't clear it within one second the system is restarted. */ static const struct { u8 reg_val; unsigned int time; } rn5t618_wdt_map[] = { { 0, 1 }, { 1, 8 }, { 2, 32 }, { 3, 128 }, }; static int rn5t618_wdt_set_timeout(struct watchdog_device *wdt_dev, unsigned int t) { struct rn5t618_wdt *wdt = watchdog_get_drvdata(wdt_dev); int ret, i; for (i = 0; i < ARRAY_SIZE(rn5t618_wdt_map); i++) { if (rn5t618_wdt_map[i].time + 1 >= t) break; } if (i == ARRAY_SIZE(rn5t618_wdt_map)) return -EINVAL; ret = regmap_update_bits(wdt->rn5t618->regmap, RN5T618_WATCHDOG, RN5T618_WATCHDOG_WDOGTIM_M, rn5t618_wdt_map[i].reg_val); if (!ret) wdt_dev->timeout = rn5t618_wdt_map[i].time; return ret; } static int rn5t618_wdt_start(struct watchdog_device *wdt_dev) { struct rn5t618_wdt *wdt = watchdog_get_drvdata(wdt_dev); int ret; ret = rn5t618_wdt_set_timeout(wdt_dev, wdt_dev->timeout); if (ret) return ret; /* enable repower-on */ ret = regmap_update_bits(wdt->rn5t618->regmap, RN5T618_REPCNT, RN5T618_REPCNT_REPWRON, RN5T618_REPCNT_REPWRON); if (ret) return ret; /* enable watchdog */ ret = regmap_update_bits(wdt->rn5t618->regmap, RN5T618_WATCHDOG, RN5T618_WATCHDOG_WDOGEN, RN5T618_WATCHDOG_WDOGEN); if (ret) return ret; /* enable watchdog interrupt */ return regmap_update_bits(wdt->rn5t618->regmap, RN5T618_PWRIREN, RN5T618_PWRIRQ_IR_WDOG, RN5T618_PWRIRQ_IR_WDOG); } static int rn5t618_wdt_stop(struct watchdog_device *wdt_dev) { struct rn5t618_wdt *wdt = watchdog_get_drvdata(wdt_dev); return regmap_update_bits(wdt->rn5t618->regmap, RN5T618_WATCHDOG, RN5T618_WATCHDOG_WDOGEN, 0); } static int rn5t618_wdt_ping(struct watchdog_device *wdt_dev) { struct rn5t618_wdt *wdt = watchdog_get_drvdata(wdt_dev); unsigned int val; int ret; /* The counter is restarted after a R/W access to watchdog register */ ret = regmap_read(wdt->rn5t618->regmap, RN5T618_WATCHDOG, &val); if (ret) return ret; ret = regmap_write(wdt->rn5t618->regmap, RN5T618_WATCHDOG, val); if (ret) return ret; /* Clear pending watchdog interrupt */ return regmap_update_bits(wdt->rn5t618->regmap, RN5T618_PWRIRQ, RN5T618_PWRIRQ_IR_WDOG, 0); } static struct watchdog_info rn5t618_wdt_info = { .options = WDIOF_SETTIMEOUT | WDIOF_MAGICCLOSE | WDIOF_KEEPALIVEPING, .identity = DRIVER_NAME, }; static const struct watchdog_ops rn5t618_wdt_ops = { .owner = THIS_MODULE, .start = rn5t618_wdt_start, .stop = rn5t618_wdt_stop, .ping = rn5t618_wdt_ping, .set_timeout = rn5t618_wdt_set_timeout, }; static int rn5t618_wdt_probe(struct platform_device *pdev) { struct rn5t618 *rn5t618 = dev_get_drvdata(pdev->dev.parent); struct rn5t618_wdt *wdt; int min_timeout, max_timeout; wdt = devm_kzalloc(&pdev->dev, sizeof(struct rn5t618_wdt), GFP_KERNEL); if (!wdt) return -ENOMEM; min_timeout = rn5t618_wdt_map[0].time; max_timeout = rn5t618_wdt_map[ARRAY_SIZE(rn5t618_wdt_map) - 1].time; wdt->rn5t618 = rn5t618; wdt->wdt_dev.info = &rn5t618_wdt_info; wdt->wdt_dev.ops = &rn5t618_wdt_ops; wdt->wdt_dev.min_timeout = min_timeout; wdt->wdt_dev.max_timeout = max_timeout; wdt->wdt_dev.timeout = max_timeout; wdt->wdt_dev.parent = &pdev->dev; watchdog_set_drvdata(&wdt->wdt_dev, wdt); watchdog_init_timeout(&wdt->wdt_dev, timeout, &pdev->dev); watchdog_set_nowayout(&wdt->wdt_dev, nowayout); platform_set_drvdata(pdev, wdt); return watchdog_register_device(&wdt->wdt_dev); } static int rn5t618_wdt_remove(struct platform_device *pdev) { struct rn5t618_wdt *wdt = platform_get_drvdata(pdev); watchdog_unregister_device(&wdt->wdt_dev); return 0; } static struct platform_driver rn5t618_wdt_driver = { .probe = rn5t618_wdt_probe, .remove = rn5t618_wdt_remove, .driver = { .name = DRIVER_NAME, }, }; module_platform_driver(rn5t618_wdt_driver); MODULE_AUTHOR("Beniamino Galvani "); MODULE_DESCRIPTION("RN5T618 watchdog driver"); MODULE_LICENSE("GPL v2"); 321e4a1f31f98194e4f6b6cae7'>patch) tree370efda701f03cccf21e02bb1fdd3b852547d75c /drivers/usb/storage/jumpshot.c parent0c744ea4f77d72b3dcebb7a8f2684633ec79be88 (diff)
tracing: Fix hwlat kthread migration
The hwlat tracer creates a kernel thread at start of the tracer. It is pinned to a single CPU and will move to the next CPU after each period of running. If the user modifies the migration thread's affinity, it will not change after that happens. The original code created the thread at the first instance it was called, but later was changed to destroy the thread after the tracer was finished, and would not be created until the next instance of the tracer was established. The code that initialized the affinity was only called on the initial instantiation of the tracer. After that, it was not initialized, and the previous affinity did not match the current newly created one, making it appear that the user modified the thread's affinity when it did not, and the thread failed to migrate again. Cc: stable@vger.kernel.org Fixes: 0330f7aa8ee6 ("tracing: Have hwlat trace migrate across tracing_cpumask CPUs") Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
Diffstat (limited to 'drivers/usb/storage/jumpshot.c')