diff options
Diffstat (limited to 'drivers/watchdog/jz4740_wdt.c')
| -rw-r--r-- | drivers/watchdog/jz4740_wdt.c | 188 |
1 files changed, 81 insertions, 107 deletions
diff --git a/drivers/watchdog/jz4740_wdt.c b/drivers/watchdog/jz4740_wdt.c index d1afdf684c18..395bde79e292 100644 --- a/drivers/watchdog/jz4740_wdt.c +++ b/drivers/watchdog/jz4740_wdt.c @@ -1,51 +1,24 @@ +// SPDX-License-Identifier: GPL-2.0-or-later /* * Copyright (C) 2010, Paul Cercueil <paul@crapouillou.net> * JZ4740 Watchdog driver - * - * 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. - * - * You should have received a copy of the GNU General Public License along - * with this program; if not, write to the Free Software Foundation, Inc., - * 675 Mass Ave, Cambridge, MA 02139, USA. - * */ +#include <linux/mfd/ingenic-tcu.h> +#include <linux/mfd/syscon.h> #include <linux/module.h> #include <linux/moduleparam.h> #include <linux/types.h> #include <linux/kernel.h> -#include <linux/miscdevice.h> #include <linux/watchdog.h> -#include <linux/init.h> #include <linux/platform_device.h> #include <linux/io.h> #include <linux/device.h> #include <linux/clk.h> #include <linux/slab.h> #include <linux/err.h> - -#include <asm/mach-jz4740/timer.h> - -#define JZ_REG_WDT_TIMER_DATA 0x0 -#define JZ_REG_WDT_COUNTER_ENABLE 0x4 -#define JZ_REG_WDT_TIMER_COUNTER 0x8 -#define JZ_REG_WDT_TIMER_CONTROL 0xC - -#define JZ_WDT_CLOCK_PCLK 0x1 -#define JZ_WDT_CLOCK_RTC 0x2 -#define JZ_WDT_CLOCK_EXT 0x4 - -#define JZ_WDT_CLOCK_DIV_SHIFT 3 - -#define JZ_WDT_CLOCK_DIV_1 (0 << JZ_WDT_CLOCK_DIV_SHIFT) -#define JZ_WDT_CLOCK_DIV_4 (1 << JZ_WDT_CLOCK_DIV_SHIFT) -#define JZ_WDT_CLOCK_DIV_16 (2 << JZ_WDT_CLOCK_DIV_SHIFT) -#define JZ_WDT_CLOCK_DIV_64 (3 << JZ_WDT_CLOCK_DIV_SHIFT) -#define JZ_WDT_CLOCK_DIV_256 (4 << JZ_WDT_CLOCK_DIV_SHIFT) -#define JZ_WDT_CLOCK_DIV_1024 (5 << JZ_WDT_CLOCK_DIV_SHIFT) +#include <linux/of.h> +#include <linux/regmap.h> #define DEFAULT_HEARTBEAT 5 #define MAX_HEARTBEAT 2048 @@ -65,15 +38,17 @@ MODULE_PARM_DESC(heartbeat, struct jz4740_wdt_drvdata { struct watchdog_device wdt; - void __iomem *base; - struct clk *rtc_clk; + struct regmap *map; + struct clk *clk; + unsigned long clk_rate; }; static int jz4740_wdt_ping(struct watchdog_device *wdt_dev) { struct jz4740_wdt_drvdata *drvdata = watchdog_get_drvdata(wdt_dev); - writew(0x0, drvdata->base + JZ_REG_WDT_TIMER_COUNTER); + regmap_write(drvdata->map, TCU_REG_WDT_TCNT, 0); + return 0; } @@ -81,33 +56,17 @@ static int jz4740_wdt_set_timeout(struct watchdog_device *wdt_dev, unsigned int new_timeout) { struct jz4740_wdt_drvdata *drvdata = watchdog_get_drvdata(wdt_dev); - unsigned int rtc_clk_rate; - unsigned int timeout_value; - unsigned short clock_div = JZ_WDT_CLOCK_DIV_1; - - rtc_clk_rate = clk_get_rate(drvdata->rtc_clk); - - timeout_value = rtc_clk_rate * new_timeout; - while (timeout_value > 0xffff) { - if (clock_div == JZ_WDT_CLOCK_DIV_1024) { - /* Requested timeout too high; - * use highest possible value. */ - timeout_value = 0xffff; - break; - } - timeout_value >>= 2; - clock_div += (1 << JZ_WDT_CLOCK_DIV_SHIFT); - } + u16 timeout_value = (u16)(drvdata->clk_rate * new_timeout); + unsigned int tcer; - writeb(0x0, drvdata->base + JZ_REG_WDT_COUNTER_ENABLE); - writew(clock_div, drvdata->base + JZ_REG_WDT_TIMER_CONTROL); + regmap_read(drvdata->map, TCU_REG_WDT_TCER, &tcer); + regmap_write(drvdata->map, TCU_REG_WDT_TCER, 0); - writew((u16)timeout_value, drvdata->base + JZ_REG_WDT_TIMER_DATA); - writew(0x0, drvdata->base + JZ_REG_WDT_TIMER_COUNTER); - writew(clock_div | JZ_WDT_CLOCK_RTC, - drvdata->base + JZ_REG_WDT_TIMER_CONTROL); + regmap_write(drvdata->map, TCU_REG_WDT_TDR, timeout_value); + regmap_write(drvdata->map, TCU_REG_WDT_TCNT, 0); - writeb(0x1, drvdata->base + JZ_REG_WDT_COUNTER_ENABLE); + if (tcer & TCU_WDT_TCER_TCEN) + regmap_write(drvdata->map, TCU_REG_WDT_TCER, TCU_WDT_TCER_TCEN); wdt_dev->timeout = new_timeout; return 0; @@ -115,9 +74,22 @@ static int jz4740_wdt_set_timeout(struct watchdog_device *wdt_dev, static int jz4740_wdt_start(struct watchdog_device *wdt_dev) { - jz4740_timer_enable_watchdog(); + struct jz4740_wdt_drvdata *drvdata = watchdog_get_drvdata(wdt_dev); + unsigned int tcer; + int ret; + + ret = clk_prepare_enable(drvdata->clk); + if (ret) + return ret; + + regmap_read(drvdata->map, TCU_REG_WDT_TCER, &tcer); + jz4740_wdt_set_timeout(wdt_dev, wdt_dev->timeout); + /* Start watchdog if it wasn't started already */ + if (!(tcer & TCU_WDT_TCER_TCEN)) + regmap_write(drvdata->map, TCU_REG_WDT_TCER, TCU_WDT_TCER_TCEN); + return 0; } @@ -125,9 +97,17 @@ static int jz4740_wdt_stop(struct watchdog_device *wdt_dev) { struct jz4740_wdt_drvdata *drvdata = watchdog_get_drvdata(wdt_dev); - jz4740_timer_disable_watchdog(); - writeb(0x0, drvdata->base + JZ_REG_WDT_COUNTER_ENABLE); + regmap_write(drvdata->map, TCU_REG_WDT_TCER, 0); + clk_disable_unprepare(drvdata->clk); + + return 0; +} +static int jz4740_wdt_restart(struct watchdog_device *wdt_dev, + unsigned long action, void *data) +{ + wdt_dev->timeout = 0; + jz4740_wdt_start(wdt_dev); return 0; } @@ -142,78 +122,73 @@ static const struct watchdog_ops jz4740_wdt_ops = { .stop = jz4740_wdt_stop, .ping = jz4740_wdt_ping, .set_timeout = jz4740_wdt_set_timeout, + .restart = jz4740_wdt_restart, +}; + +#ifdef CONFIG_OF +static const struct of_device_id jz4740_wdt_of_matches[] = { + { .compatible = "ingenic,jz4740-watchdog", }, + { .compatible = "ingenic,jz4780-watchdog", }, + { /* sentinel */ } }; +MODULE_DEVICE_TABLE(of, jz4740_wdt_of_matches); +#endif static int jz4740_wdt_probe(struct platform_device *pdev) { + struct device *dev = &pdev->dev; struct jz4740_wdt_drvdata *drvdata; struct watchdog_device *jz4740_wdt; - struct resource *res; + long rate; int ret; - drvdata = devm_kzalloc(&pdev->dev, sizeof(struct jz4740_wdt_drvdata), + drvdata = devm_kzalloc(dev, sizeof(struct jz4740_wdt_drvdata), GFP_KERNEL); - if (!drvdata) { - dev_err(&pdev->dev, "Unable to alloacate watchdog device\n"); + if (!drvdata) return -ENOMEM; + + drvdata->clk = devm_clk_get(&pdev->dev, "wdt"); + if (IS_ERR(drvdata->clk)) { + dev_err(&pdev->dev, "cannot find WDT clock\n"); + return PTR_ERR(drvdata->clk); } - if (heartbeat < 1 || heartbeat > MAX_HEARTBEAT) - heartbeat = DEFAULT_HEARTBEAT; + /* Set smallest clock possible */ + rate = clk_round_rate(drvdata->clk, 1); + if (rate < 0) + return rate; + ret = clk_set_rate(drvdata->clk, rate); + if (ret) + return ret; + + drvdata->clk_rate = rate; jz4740_wdt = &drvdata->wdt; jz4740_wdt->info = &jz4740_wdt_info; jz4740_wdt->ops = &jz4740_wdt_ops; - jz4740_wdt->timeout = heartbeat; jz4740_wdt->min_timeout = 1; - jz4740_wdt->max_timeout = MAX_HEARTBEAT; + jz4740_wdt->max_timeout = 0xffff / rate; + jz4740_wdt->timeout = clamp(heartbeat, + jz4740_wdt->min_timeout, + jz4740_wdt->max_timeout); + jz4740_wdt->parent = dev; watchdog_set_nowayout(jz4740_wdt, nowayout); watchdog_set_drvdata(jz4740_wdt, drvdata); - res = platform_get_resource(pdev, IORESOURCE_MEM, 0); - drvdata->base = devm_ioremap_resource(&pdev->dev, res); - if (IS_ERR(drvdata->base)) { - ret = PTR_ERR(drvdata->base); - goto err_out; - } - - drvdata->rtc_clk = clk_get(&pdev->dev, "rtc"); - if (IS_ERR(drvdata->rtc_clk)) { - dev_err(&pdev->dev, "cannot find RTC clock\n"); - ret = PTR_ERR(drvdata->rtc_clk); - goto err_out; + drvdata->map = device_node_to_regmap(dev->parent->of_node); + if (IS_ERR(drvdata->map)) { + dev_err(dev, "regmap not found\n"); + return PTR_ERR(drvdata->map); } - ret = watchdog_register_device(&drvdata->wdt); - if (ret < 0) - goto err_disable_clk; - - platform_set_drvdata(pdev, drvdata); - return 0; - -err_disable_clk: - clk_put(drvdata->rtc_clk); -err_out: - return ret; -} - -static int jz4740_wdt_remove(struct platform_device *pdev) -{ - struct jz4740_wdt_drvdata *drvdata = platform_get_drvdata(pdev); - - jz4740_wdt_stop(&drvdata->wdt); - watchdog_unregister_device(&drvdata->wdt); - clk_put(drvdata->rtc_clk); - - return 0; + return devm_watchdog_register_device(dev, &drvdata->wdt); } static struct platform_driver jz4740_wdt_driver = { .probe = jz4740_wdt_probe, - .remove = jz4740_wdt_remove, .driver = { .name = "jz4740-wdt", - .owner = THIS_MODULE, + .of_match_table = of_match_ptr(jz4740_wdt_of_matches), }, }; @@ -222,5 +197,4 @@ module_platform_driver(jz4740_wdt_driver); MODULE_AUTHOR("Paul Cercueil <paul@crapouillou.net>"); MODULE_DESCRIPTION("jz4740 Watchdog Driver"); MODULE_LICENSE("GPL"); -MODULE_ALIAS_MISCDEV(WATCHDOG_MINOR); MODULE_ALIAS("platform:jz4740-wdt"); |