On Fri, Jan 10, 2020 at 3:04 PM Jiaxin Yu <jiaxin.yu@xxxxxxxxxxxx> wrote: > > Add reset controller API in watchdog driver. > Besides watchdog, MTK toprgu module alsa provide sub-system (eg, audio, > camera, codec and connectivity) software reset functionality. > > Signed-off-by: yong.liang <yong.liang@xxxxxxxxxxxx> > Signed-off-by: Jiaxin Yu <jiaxin.yu@xxxxxxxxxxxx> Since there was a doubt about the history of the tags, trying to detangle: > Reviewed-by: Yingjoe Chen <yingjoe.chen@xxxxxxxxxxxx> > Reviewed-by: Philipp Zabel <p.zabel@xxxxxxxxxxxxxx> This comes from v7 (https://patchwork.kernel.org/patch/11311039/), that also had MT2712, but otherwise the patch is functionally similar. > Reviewed-by: Rob Herring <robh@xxxxxxxxxx> > Reviewed-by: Guenter Roeck <groeck7@xxxxxxxxx> I don't see these tags anywhere in the history, please drop them. > --- > drivers/watchdog/mtk_wdt.c | 99 +++++++++++++++++++++++++++++++++++++- > 1 file changed, 98 insertions(+), 1 deletion(-) > > diff --git a/drivers/watchdog/mtk_wdt.c b/drivers/watchdog/mtk_wdt.c > index 9c3d0033260d..e88aacb0404d 100644 > --- a/drivers/watchdog/mtk_wdt.c > +++ b/drivers/watchdog/mtk_wdt.c > @@ -9,6 +9,8 @@ > * Based on sunxi_wdt.c > */ > > +#include <dt-bindings/reset-controller/mt8183-resets.h> > +#include <linux/delay.h> > #include <linux/err.h> > #include <linux/init.h> > #include <linux/io.h> > @@ -16,10 +18,11 @@ > #include <linux/module.h> > #include <linux/moduleparam.h> > #include <linux/of.h> > +#include <linux/of_device.h> > #include <linux/platform_device.h> > +#include <linux/reset-controller.h> > #include <linux/types.h> > #include <linux/watchdog.h> > -#include <linux/delay.h> > > #define WDT_MAX_TIMEOUT 31 > #define WDT_MIN_TIMEOUT 1 > @@ -44,6 +47,9 @@ > #define WDT_SWRST 0x14 > #define WDT_SWRST_KEY 0x1209 > > +#define WDT_SWSYSRST 0x18U > +#define WDT_SWSYS_RST_KEY 0x88000000 > + > #define DRV_NAME "mtk-wdt" > #define DRV_VERSION "1.0" > > @@ -53,8 +59,90 @@ static unsigned int timeout; > struct mtk_wdt_dev { > struct watchdog_device wdt_dev; > void __iomem *wdt_base; > + spinlock_t lock; /* protects WDT_SWSYSRST reg */ > + struct reset_controller_dev rcdev; > +}; > + > +struct mtk_wdt_data { > + int toprgu_sw_rst_num; > }; > > +static const struct mtk_wdt_data mt8183_data = { > + .toprgu_sw_rst_num = MT8183_TOPRGU_SW_RST_NUM, > +}; > + > +static int toprgu_reset_update(struct reset_controller_dev *rcdev, > + unsigned long id, bool assert) > +{ > + unsigned int tmp; > + unsigned long flags; > + struct mtk_wdt_dev *data = > + container_of(rcdev, struct mtk_wdt_dev, rcdev); > + > + spin_lock_irqsave(&data->lock, flags); > + > + tmp = readl(data->wdt_base + WDT_SWSYSRST); > + if (assert) > + tmp |= BIT(id); > + else > + tmp &= ~BIT(id); > + tmp |= WDT_SWSYS_RST_KEY; > + writel(tmp, data->wdt_base + WDT_SWSYSRST); > + > + spin_unlock_irqrestore(&data->lock, flags); > + > + return 0; > +} > + > +static int toprgu_reset_assert(struct reset_controller_dev *rcdev, > + unsigned long id) > +{ > + return toprgu_reset_update(rcdev, id, true); > +} > + > +static int toprgu_reset_deassert(struct reset_controller_dev *rcdev, > + unsigned long id) > +{ > + return toprgu_reset_update(rcdev, id, false); > +} > + > +static int toprgu_reset(struct reset_controller_dev *rcdev, > + unsigned long id) > +{ > + int ret; > + > + ret = toprgu_reset_assert(rcdev, id); > + if (ret) > + return ret; > + > + return toprgu_reset_deassert(rcdev, id); > +} > + > +static const struct reset_control_ops toprgu_reset_ops = { > + .assert = toprgu_reset_assert, > + .deassert = toprgu_reset_deassert, > + .reset = toprgu_reset, > +}; > + > +static int toprgu_register_reset_controller(struct platform_device *pdev, > + int rst_num) > +{ > + int ret; > + struct mtk_wdt_dev *mtk_wdt = platform_get_drvdata(pdev); > + > + spin_lock_init(&mtk_wdt->lock); > + > + mtk_wdt->rcdev.owner = THIS_MODULE; > + mtk_wdt->rcdev.nr_resets = rst_num; > + mtk_wdt->rcdev.ops = &toprgu_reset_ops; > + mtk_wdt->rcdev.of_node = pdev->dev.of_node; > + ret = devm_reset_controller_register(&pdev->dev, &mtk_wdt->rcdev); > + if (ret != 0) > + dev_err(&pdev->dev, > + "couldn't register wdt reset controller: %d\n", ret); > + return ret; > +} > + > static int mtk_wdt_restart(struct watchdog_device *wdt_dev, > unsigned long action, void *data) > { > @@ -155,6 +243,7 @@ static int mtk_wdt_probe(struct platform_device *pdev) > { > struct device *dev = &pdev->dev; > struct mtk_wdt_dev *mtk_wdt; > + const struct mtk_wdt_data *wdt_data; > int err; > > mtk_wdt = devm_kzalloc(dev, sizeof(*mtk_wdt), GFP_KERNEL); > @@ -190,6 +279,13 @@ static int mtk_wdt_probe(struct platform_device *pdev) > dev_info(dev, "Watchdog enabled (timeout=%d sec, nowayout=%d)\n", > mtk_wdt->wdt_dev.timeout, nowayout); > > + wdt_data = of_device_get_match_data(dev); > + if (wdt_data) { > + err = toprgu_register_reset_controller(pdev, > + wdt_data->toprgu_sw_rst_num); > + if (err) > + return err; > + } > return 0; > } > > @@ -219,6 +315,7 @@ static int mtk_wdt_resume(struct device *dev) > > static const struct of_device_id mtk_wdt_dt_ids[] = { > { .compatible = "mediatek,mt6589-wdt" }, > + { .compatible = "mediatek,mt8183-wdt", .data = &mt8183_data }, > { /* sentinel */ } > }; > MODULE_DEVICE_TABLE(of, mtk_wdt_dt_ids); > -- > 2.18.0