| Message ID | 20241121064046.3724726-6-tmyu0@nuvoton.com |
|---|---|
| State | New |
| Headers | show |
| Series | Add Nuvoton NCT6694 MFD drivers | expand |
On 11/20/24 22:40, Ming Yu wrote: > This driver supports Watchdog timer functionality for NCT6694 MFD > device based on USB interface. > > Signed-off-by: Ming Yu <tmyu0@nuvoton.com> > --- > MAINTAINERS | 1 + > drivers/watchdog/Kconfig | 11 ++ > drivers/watchdog/Makefile | 1 + > drivers/watchdog/nct6694_wdt.c | 277 +++++++++++++++++++++++++++++++++ > 4 files changed, 290 insertions(+) > create mode 100644 drivers/watchdog/nct6694_wdt.c > > diff --git a/MAINTAINERS b/MAINTAINERS > index eb5d46825e71..496fe7d5a23f 100644 > --- a/MAINTAINERS > +++ b/MAINTAINERS > @@ -16549,6 +16549,7 @@ F: drivers/gpio/gpio-nct6694.c > F: drivers/i2c/busses/i2c-nct6694.c > F: drivers/mfd/nct6694.c > F: drivers/net/can/nct6694_canfd.c > +F: drivers/watchdog/nct6694_wdt.c > F: include/linux/mfd/nct6694.h > > NVIDIA (rivafb and nvidiafb) FRAMEBUFFER DRIVER > diff --git a/drivers/watchdog/Kconfig b/drivers/watchdog/Kconfig > index 2333476a42c0..851c1f17712d 100644 > --- a/drivers/watchdog/Kconfig > +++ b/drivers/watchdog/Kconfig > @@ -739,6 +739,17 @@ config MAX77620_WATCHDOG > MAX77620 chips. To compile this driver as a module, > choose M here: the module will be called max77620_wdt. > > +config NCT6694_WATCHDOG > + tristate "Nuvoton NCT6694 watchdog support" > + depends on MFD_NCT6694 > + select WATCHDOG_CORE > + help > + If you say yes to this option, support will be included for Nuvoton > + NCT6694, a USB device to watchdog timer. > + It is a peripheral expander, not a "USB device to watchdog timer". Watchdog is only a small part of its functionality. > + This driver can also be built as a module. If so, the module will > + be called nct6694_wdt. > + > config IMX2_WDT > tristate "IMX2+ Watchdog" > depends on ARCH_MXC || ARCH_LAYERSCAPE || COMPILE_TEST > diff --git a/drivers/watchdog/Makefile b/drivers/watchdog/Makefile > index 386d88d89fe5..8355893b4435 100644 > --- a/drivers/watchdog/Makefile > +++ b/drivers/watchdog/Makefile > @@ -232,6 +232,7 @@ obj-$(CONFIG_WM831X_WATCHDOG) += wm831x_wdt.o > obj-$(CONFIG_WM8350_WATCHDOG) += wm8350_wdt.o > obj-$(CONFIG_MAX63XX_WATCHDOG) += max63xx_wdt.o > obj-$(CONFIG_MAX77620_WATCHDOG) += max77620_wdt.o > +obj-$(CONFIG_NCT6694_WATCHDOG) += nct6694_wdt.o > obj-$(CONFIG_ZIIRAVE_WATCHDOG) += ziirave_wdt.o > obj-$(CONFIG_SOFT_WATCHDOG) += softdog.o > obj-$(CONFIG_MENF21BMC_WATCHDOG) += menf21bmc_wdt.o > diff --git a/drivers/watchdog/nct6694_wdt.c b/drivers/watchdog/nct6694_wdt.c > new file mode 100644 > index 000000000000..7d2c8d5c6fa3 > --- /dev/null > +++ b/drivers/watchdog/nct6694_wdt.c > @@ -0,0 +1,277 @@ > +// SPDX-License-Identifier: GPL-2.0 > +/* > + * Nuvoton NCT6694 WDT driver based on USB interface. > + * > + * Copyright (C) 2024 Nuvoton Technology Corp. > + */ > + > +#include <linux/kernel.h> > +#include <linux/mfd/core.h> > +#include <linux/mfd/nct6694.h> > +#include <linux/module.h> > +#include <linux/platform_device.h> > +#include <linux/slab.h> > +#include <linux/watchdog.h> > + > +#define DRVNAME "nct6694-wdt" > + > +#define NCT6694_DEFAULT_TIMEOUT 10 > +#define NCT6694_DEFAULT_PRETIMEOUT 0 > + > +/* Host interface */ > +#define NCT6694_WDT_MOD 0x07 > + > +/* Message Channel*/ > +/* Command 00h */ > +#define NCT6694_WDT_CMD0_LEN 0x0F > +#define NCT6694_WDT_CMD0_OFFSET(idx) (idx ? 0x0100 : 0x0000) /* OFFSET = SEL|CMD */ > + > +/* Command 01h */ > +#define NCT6694_WDT_CMD1_LEN 0x08 > +#define NCT6694_WDT_CMD1_OFFSET(idx) (idx ? 0x0101 : 0x0001) /* OFFSET = SEL|CMD */ > + > +static unsigned int timeout = NCT6694_DEFAULT_TIMEOUT; > +module_param(timeout, int, 0); > +MODULE_PARM_DESC(timeout, "Watchdog timeout in seconds"); > + > +static unsigned int pretimeout = NCT6694_DEFAULT_PRETIMEOUT; > +module_param(pretimeout, int, 0); > +MODULE_PARM_DESC(pretimeout, "Watchdog pre-timeout in seconds"); > + > +static bool nowayout = WATCHDOG_NOWAYOUT; > +module_param(nowayout, bool, 0); > +MODULE_PARM_DESC(nowayout, "Watchdog cannot be stopped once started (default=" > + __MODULE_STRING(WATCHDOG_NOWAYOUT) ")"); > + > +enum { > + NCT6694_ACTION_NONE = 0, > + NCT6694_ACTION_SIRQ, > + NCT6694_ACTION_GPO, > +}; > + > +struct __packed nct6694_wdt_cmd0 { > + __le32 pretimeout; > + __le32 timeout; > + u8 owner; > + u8 scratch; > + u8 control; > + u8 status; > + __le32 countdown; > +}; > + > +struct __packed nct6694_wdt_cmd1 { > + u32 wdt_cmd; > + u32 reserved; > +}; > + > +struct nct6694_wdt_data { > + struct watchdog_device wdev; > + struct device *dev; > + struct nct6694 *nct6694; > + struct mutex lock; > + unsigned char *xmit_buf; > + unsigned int wdev_idx; > +}; > + > +static int nct6694_wdt_setting(struct watchdog_device *wdev, > + u32 timeout_val, u8 timeout_act, > + u32 pretimeout_val, u8 pretimeout_act) > +{ > + struct nct6694_wdt_data *data = watchdog_get_drvdata(wdev); > + struct nct6694_wdt_cmd0 *buf = (struct nct6694_wdt_cmd0 *)data->xmit_buf; > + struct nct6694 *nct6694 = data->nct6694; > + unsigned int timeout_fmt, pretimeout_fmt; > + > + guard(mutex)(&data->lock); > + > + if (pretimeout_val == 0) > + pretimeout_act = NCT6694_ACTION_NONE; > + > + timeout_fmt = (timeout_val * 1000) | (timeout_act << 24); > + pretimeout_fmt = (pretimeout_val * 1000) | (pretimeout_act << 24); > + > + memset(buf, 0, NCT6694_WDT_CMD0_LEN); > + buf->timeout = cpu_to_le32(timeout_fmt); > + buf->pretimeout = cpu_to_le32(pretimeout_fmt); > + > + return nct6694_write_msg(nct6694, NCT6694_WDT_MOD, > + NCT6694_WDT_CMD0_OFFSET(data->wdev_idx), > + NCT6694_WDT_CMD0_LEN, buf); > +} > + > +static int nct6694_wdt_start(struct watchdog_device *wdev) > +{ > + struct nct6694_wdt_data *data = watchdog_get_drvdata(wdev); > + int ret; > + > + ret = nct6694_wdt_setting(wdev, wdev->timeout, NCT6694_ACTION_GPO, > + wdev->pretimeout, NCT6694_ACTION_GPO); > + if (ret) > + return ret; > + > + dev_info(data->dev, "Setting WDT(%d): timeout = %d, pretimeout = %d\n", > + data->wdev_idx, wdev->timeout, wdev->pretimeout); > + This is logging noise. Drop or set as debug message. > + return ret; > +} > + > +static int nct6694_wdt_stop(struct watchdog_device *wdev) > +{ > + struct nct6694_wdt_data *data = watchdog_get_drvdata(wdev); > + struct nct6694_wdt_cmd1 *buf = (struct nct6694_wdt_cmd1 *)data->xmit_buf; > + struct nct6694 *nct6694 = data->nct6694; > + > + guard(mutex)(&data->lock); > + > + memcpy(buf, "WDTC", 4); > + buf->reserved = 0; > + > + return nct6694_write_msg(nct6694, NCT6694_WDT_MOD, > + NCT6694_WDT_CMD1_OFFSET(data->wdev_idx), > + NCT6694_WDT_CMD1_LEN, buf); > +} > + > +static int nct6694_wdt_ping(struct watchdog_device *wdev) > +{ > + struct nct6694_wdt_data *data = watchdog_get_drvdata(wdev); > + struct nct6694_wdt_cmd1 *buf = (struct nct6694_wdt_cmd1 *)data->xmit_buf; > + struct nct6694 *nct6694 = data->nct6694; > + > + guard(mutex)(&data->lock); > + memcpy(buf, "WDTS", 4); > + buf->reserved = 0; > + > + return nct6694_write_msg(nct6694, NCT6694_WDT_MOD, > + NCT6694_WDT_CMD1_OFFSET(data->wdev_idx), > + NCT6694_WDT_CMD1_LEN, buf); > +} > + > +static int nct6694_wdt_set_timeout(struct watchdog_device *wdev, > + unsigned int timeout) > +{ > + struct nct6694_wdt_data *data = watchdog_get_drvdata(wdev); > + int ret; > + > + if (timeout < wdev->pretimeout) { > + dev_warn(data->dev, "pretimeout < timeout. Setting to zero\n"); > + wdev->pretimeout = 0; > + } > + This is only necessary if the pretimeout was not validated during probe since otherwise the watchdog core does the check. Please validate it there. > + ret = nct6694_wdt_setting(wdev, timeout, NCT6694_ACTION_GPO, > + wdev->pretimeout, NCT6694_ACTION_GPO); > + if (ret) > + return ret; > + > + wdev->timeout = timeout; > + > + return ret; ret == 0 here, so return 0. > +} > + > +static int nct6694_wdt_set_pretimeout(struct watchdog_device *wdev, > + unsigned int pretimeout) > +{ > + int ret; > + > + ret = nct6694_wdt_setting(wdev, wdev->timeout, NCT6694_ACTION_GPO, > + pretimeout, NCT6694_ACTION_GPO); > + if (ret) > + return ret; > + > + wdev->pretimeout = pretimeout; > + > + return ret; ret == 0 here, so return 0. > +} > + > +static unsigned int nct6694_wdt_get_time(struct watchdog_device *wdev) > +{ > + struct nct6694_wdt_data *data = watchdog_get_drvdata(wdev); > + struct nct6694_wdt_cmd0 *buf = (struct nct6694_wdt_cmd0 *)data->xmit_buf; > + struct nct6694 *nct6694 = data->nct6694; > + unsigned int timeleft_ms; > + int ret; > + > + guard(mutex)(&data->lock); > + > + ret = nct6694_read_msg(nct6694, NCT6694_WDT_MOD, > + NCT6694_WDT_CMD0_OFFSET(data->wdev_idx), > + NCT6694_WDT_CMD0_LEN, buf); > + if (ret) > + return ret; The function does not return an error code. Return 0 instead. > + > + timeleft_ms = le32_to_cpu(buf->countdown); > + > + return timeleft_ms / 1000; > +} > + > +static const struct watchdog_info nct6694_wdt_info = { > + .options = WDIOF_SETTIMEOUT | > + WDIOF_KEEPALIVEPING | > + WDIOF_MAGICCLOSE | > + WDIOF_PRETIMEOUT, > + .identity = DRVNAME, > +}; > + > +static const struct watchdog_ops nct6694_wdt_ops = { > + .owner = THIS_MODULE, > + .start = nct6694_wdt_start, > + .stop = nct6694_wdt_stop, > + .set_timeout = nct6694_wdt_set_timeout, > + .set_pretimeout = nct6694_wdt_set_pretimeout, > + .get_timeleft = nct6694_wdt_get_time, > + .ping = nct6694_wdt_ping, > +}; > + > +static int nct6694_wdt_probe(struct platform_device *pdev) > +{ > + const struct mfd_cell *cell = mfd_get_cell(pdev); > + struct device *dev = &pdev->dev; > + struct nct6694 *nct6694 = dev_get_drvdata(pdev->dev.parent); > + struct nct6694_wdt_data *data; > + struct watchdog_device *wdev; > + > + data = devm_kzalloc(&pdev->dev, sizeof(*data), GFP_KERNEL); > + if (!data) > + return -ENOMEM; > + > + data->xmit_buf = devm_kcalloc(dev, NCT6694_MAX_PACKET_SZ, > + sizeof(unsigned char), GFP_KERNEL); > + if (!data->xmit_buf) > + return -ENOMEM; > + > + data->dev = dev; > + data->nct6694 = nct6694; > + data->wdev_idx = cell->id; > + > + wdev = &data->wdev; > + wdev->info = &nct6694_wdt_info; > + wdev->ops = &nct6694_wdt_ops; > + wdev->timeout = timeout; > + wdev->pretimeout = pretimeout; pretimeout should be validated here. > + wdev->min_timeout = 1; > + wdev->max_timeout = 255; > + > + mutex_init(&data->lock); > + > + platform_set_drvdata(pdev, data); > + > + /* Register watchdog timer device to WDT framework */ > + watchdog_set_drvdata(&data->wdev, data); > + watchdog_init_timeout(&data->wdev, timeout, dev); > + watchdog_set_nowayout(&data->wdev, nowayout); > + watchdog_stop_on_reboot(&data->wdev); > + > + return devm_watchdog_register_device(dev, &data->wdev); > +} > + > +static struct platform_driver nct6694_wdt_driver = { > + .driver = { > + .name = DRVNAME, > + }, > + .probe = nct6694_wdt_probe, > +}; > + > +module_platform_driver(nct6694_wdt_driver); > + > +MODULE_DESCRIPTION("USB-WDT driver for NCT6694"); > +MODULE_AUTHOR("Ming Yu <tmyu0@nuvoton.com>"); > +MODULE_LICENSE("GPL");
Dear Guenter, Thank you for your comments, Guenter Roeck <linux@roeck-us.net> 於 2024年11月21日 週四 下午10:15寫道： > > +config NCT6694_WATCHDOG > > + tristate "Nuvoton NCT6694 watchdog support" > > + depends on MFD_NCT6694 > > + select WATCHDOG_CORE > > + help > > + If you say yes to this option, support will be included for Nuvoton > > + NCT6694, a USB device to watchdog timer. > > + > > It is a peripheral expander, not a "USB device to watchdog timer". Watchdog is only > a small part of its functionality. > Understood. I will make the modifications in v3. > > + This driver can also be built as a module. If so, the module will > > + be called nct6694_wdt. ... > > + ret = nct6694_wdt_setting(wdev, wdev->timeout, NCT6694_ACTION_GPO, > > + wdev->pretimeout, NCT6694_ACTION_GPO); > > + if (ret) > > + return ret; > > + > > + dev_info(data->dev, "Setting WDT(%d): timeout = %d, pretimeout = %d\n", > > + data->wdev_idx, wdev->timeout, wdev->pretimeout); > > + > > This is logging noise. Drop or set as debug message. > Okay, I'll drop it in v3. > > + return ret; > > +} ... > > +static int nct6694_wdt_set_timeout(struct watchdog_device *wdev, > > + unsigned int timeout) > > +{ > > + struct nct6694_wdt_data *data = watchdog_get_drvdata(wdev); > > + int ret; > > + > > + if (timeout < wdev->pretimeout) { > > + dev_warn(data->dev, "pretimeout < timeout. Setting to zero\n"); > > + wdev->pretimeout = 0; > > + } > > + > This is only necessary if the pretimeout was not validated during probe > since otherwise the watchdog core does the check. Please validate it there. > Understood. I will make the modifications in v3. > > + ret = nct6694_wdt_setting(wdev, timeout, NCT6694_ACTION_GPO, > > + wdev->pretimeout, NCT6694_ACTION_GPO); > > + if (ret) > > + return ret; > > + > > + wdev->timeout = timeout; > > + > > + return ret; > > ret == 0 here, so return 0. > Okay, fix it in v3. > > +} > > + > > +static int nct6694_wdt_set_pretimeout(struct watchdog_device *wdev, > > + unsigned int pretimeout) > > +{ > > + int ret; > > + > > + ret = nct6694_wdt_setting(wdev, wdev->timeout, NCT6694_ACTION_GPO, > > + pretimeout, NCT6694_ACTION_GPO); > > + if (ret) > > + return ret; > > + > > + wdev->pretimeout = pretimeout; > > + > > + return ret; > > ret == 0 here, so return 0. > Okay, fix it in v3. > > +} > > + > > +static unsigned int nct6694_wdt_get_time(struct watchdog_device *wdev) > > +{ > > + struct nct6694_wdt_data *data = watchdog_get_drvdata(wdev); > > + struct nct6694_wdt_cmd0 *buf = (struct nct6694_wdt_cmd0 *)data->xmit_buf; > > + struct nct6694 *nct6694 = data->nct6694; > > + unsigned int timeleft_ms; > > + int ret; > > + > > + guard(mutex)(&data->lock); > > + > > + ret = nct6694_read_msg(nct6694, NCT6694_WDT_MOD, > > + NCT6694_WDT_CMD0_OFFSET(data->wdev_idx), > > + NCT6694_WDT_CMD0_LEN, buf); > > + if (ret) > > + return ret; > > The function does not return an error code. Return 0 instead. Okay, fix it in v3. > > + > > + timeleft_ms = le32_to_cpu(buf->countdown); > > + > > + return timeleft_ms / 1000; > > +} ... > > + wdev = &data->wdev; > > + wdev->info = &nct6694_wdt_info; > > + wdev->ops = &nct6694_wdt_ops; > > + wdev->timeout = timeout; > > + wdev->pretimeout = pretimeout; > > pretimeout should be validated here. > Understood. I will make the modifications in v3. Best regards, Ming
diff --git a/MAINTAINERS b/MAINTAINERS index eb5d46825e71..496fe7d5a23f 100644 --- a/MAINTAINERS +++ b/MAINTAINERS @@ -16549,6 +16549,7 @@ F: drivers/gpio/gpio-nct6694.c F: drivers/i2c/busses/i2c-nct6694.c F: drivers/mfd/nct6694.c F: drivers/net/can/nct6694_canfd.c +F: drivers/watchdog/nct6694_wdt.c F: include/linux/mfd/nct6694.h NVIDIA (rivafb and nvidiafb) FRAMEBUFFER DRIVER diff --git a/drivers/watchdog/Kconfig b/drivers/watchdog/Kconfig index 2333476a42c0..851c1f17712d 100644 --- a/drivers/watchdog/Kconfig +++ b/drivers/watchdog/Kconfig @@ -739,6 +739,17 @@ config MAX77620_WATCHDOG MAX77620 chips. To compile this driver as a module, choose M here: the module will be called max77620_wdt. +config NCT6694_WATCHDOG + tristate "Nuvoton NCT6694 watchdog support" + depends on MFD_NCT6694 + select WATCHDOG_CORE + help + If you say yes to this option, support will be included for Nuvoton + NCT6694, a USB device to watchdog timer. + + This driver can also be built as a module. If so, the module will + be called nct6694_wdt. + config IMX2_WDT tristate "IMX2+ Watchdog" depends on ARCH_MXC || ARCH_LAYERSCAPE || COMPILE_TEST diff --git a/drivers/watchdog/Makefile b/drivers/watchdog/Makefile index 386d88d89fe5..8355893b4435 100644 --- a/drivers/watchdog/Makefile +++ b/drivers/watchdog/Makefile @@ -232,6 +232,7 @@ obj-$(CONFIG_WM831X_WATCHDOG) += wm831x_wdt.o obj-$(CONFIG_WM8350_WATCHDOG) += wm8350_wdt.o obj-$(CONFIG_MAX63XX_WATCHDOG) += max63xx_wdt.o obj-$(CONFIG_MAX77620_WATCHDOG) += max77620_wdt.o +obj-$(CONFIG_NCT6694_WATCHDOG) += nct6694_wdt.o obj-$(CONFIG_ZIIRAVE_WATCHDOG) += ziirave_wdt.o obj-$(CONFIG_SOFT_WATCHDOG) += softdog.o obj-$(CONFIG_MENF21BMC_WATCHDOG) += menf21bmc_wdt.o diff --git a/drivers/watchdog/nct6694_wdt.c b/drivers/watchdog/nct6694_wdt.c new file mode 100644 index 000000000000..7d2c8d5c6fa3 --- /dev/null +++ b/drivers/watchdog/nct6694_wdt.c @@ -0,0 +1,277 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * Nuvoton NCT6694 WDT driver based on USB interface. + * + * Copyright (C) 2024 Nuvoton Technology Corp. + */ + +#include <linux/kernel.h> +#include <linux/mfd/core.h> +#include <linux/mfd/nct6694.h> +#include <linux/module.h> +#include <linux/platform_device.h> +#include <linux/slab.h> +#include <linux/watchdog.h> + +#define DRVNAME "nct6694-wdt" + +#define NCT6694_DEFAULT_TIMEOUT 10 +#define NCT6694_DEFAULT_PRETIMEOUT 0 + +/* Host interface */ +#define NCT6694_WDT_MOD 0x07 + +/* Message Channel*/ +/* Command 00h */ +#define NCT6694_WDT_CMD0_LEN 0x0F +#define NCT6694_WDT_CMD0_OFFSET(idx) (idx ? 0x0100 : 0x0000) /* OFFSET = SEL|CMD */ + +/* Command 01h */ +#define NCT6694_WDT_CMD1_LEN 0x08 +#define NCT6694_WDT_CMD1_OFFSET(idx) (idx ? 0x0101 : 0x0001) /* OFFSET = SEL|CMD */ + +static unsigned int timeout = NCT6694_DEFAULT_TIMEOUT; +module_param(timeout, int, 0); +MODULE_PARM_DESC(timeout, "Watchdog timeout in seconds"); + +static unsigned int pretimeout = NCT6694_DEFAULT_PRETIMEOUT; +module_param(pretimeout, int, 0); +MODULE_PARM_DESC(pretimeout, "Watchdog pre-timeout in seconds"); + +static bool nowayout = WATCHDOG_NOWAYOUT; +module_param(nowayout, bool, 0); +MODULE_PARM_DESC(nowayout, "Watchdog cannot be stopped once started (default=" + __MODULE_STRING(WATCHDOG_NOWAYOUT) ")"); + +enum { + NCT6694_ACTION_NONE = 0, + NCT6694_ACTION_SIRQ, + NCT6694_ACTION_GPO, +}; + +struct __packed nct6694_wdt_cmd0 { + __le32 pretimeout; + __le32 timeout; + u8 owner; + u8 scratch; + u8 control; + u8 status; + __le32 countdown; +}; + +struct __packed nct6694_wdt_cmd1 { + u32 wdt_cmd; + u32 reserved; +}; + +struct nct6694_wdt_data { + struct watchdog_device wdev; + struct device *dev; + struct nct6694 *nct6694; + struct mutex lock; + unsigned char *xmit_buf; + unsigned int wdev_idx; +}; + +static int nct6694_wdt_setting(struct watchdog_device *wdev, + u32 timeout_val, u8 timeout_act, + u32 pretimeout_val, u8 pretimeout_act) +{ + struct nct6694_wdt_data *data = watchdog_get_drvdata(wdev); + struct nct6694_wdt_cmd0 *buf = (struct nct6694_wdt_cmd0 *)data->xmit_buf; + struct nct6694 *nct6694 = data->nct6694; + unsigned int timeout_fmt, pretimeout_fmt; + + guard(mutex)(&data->lock); + + if (pretimeout_val == 0) + pretimeout_act = NCT6694_ACTION_NONE; + + timeout_fmt = (timeout_val * 1000) | (timeout_act << 24); + pretimeout_fmt = (pretimeout_val * 1000) | (pretimeout_act << 24); + + memset(buf, 0, NCT6694_WDT_CMD0_LEN); + buf->timeout = cpu_to_le32(timeout_fmt); + buf->pretimeout = cpu_to_le32(pretimeout_fmt); + + return nct6694_write_msg(nct6694, NCT6694_WDT_MOD, + NCT6694_WDT_CMD0_OFFSET(data->wdev_idx), + NCT6694_WDT_CMD0_LEN, buf); +} + +static int nct6694_wdt_start(struct watchdog_device *wdev) +{ + struct nct6694_wdt_data *data = watchdog_get_drvdata(wdev); + int ret; + + ret = nct6694_wdt_setting(wdev, wdev->timeout, NCT6694_ACTION_GPO, + wdev->pretimeout, NCT6694_ACTION_GPO); + if (ret) + return ret; + + dev_info(data->dev, "Setting WDT(%d): timeout = %d, pretimeout = %d\n", + data->wdev_idx, wdev->timeout, wdev->pretimeout); + + return ret; +} + +static int nct6694_wdt_stop(struct watchdog_device *wdev) +{ + struct nct6694_wdt_data *data = watchdog_get_drvdata(wdev); + struct nct6694_wdt_cmd1 *buf = (struct nct6694_wdt_cmd1 *)data->xmit_buf; + struct nct6694 *nct6694 = data->nct6694; + + guard(mutex)(&data->lock); + + memcpy(buf, "WDTC", 4); + buf->reserved = 0; + + return nct6694_write_msg(nct6694, NCT6694_WDT_MOD, + NCT6694_WDT_CMD1_OFFSET(data->wdev_idx), + NCT6694_WDT_CMD1_LEN, buf); +} + +static int nct6694_wdt_ping(struct watchdog_device *wdev) +{ + struct nct6694_wdt_data *data = watchdog_get_drvdata(wdev); + struct nct6694_wdt_cmd1 *buf = (struct nct6694_wdt_cmd1 *)data->xmit_buf; + struct nct6694 *nct6694 = data->nct6694; + + guard(mutex)(&data->lock); + memcpy(buf, "WDTS", 4); + buf->reserved = 0; + + return nct6694_write_msg(nct6694, NCT6694_WDT_MOD, + NCT6694_WDT_CMD1_OFFSET(data->wdev_idx), + NCT6694_WDT_CMD1_LEN, buf); +} + +static int nct6694_wdt_set_timeout(struct watchdog_device *wdev, + unsigned int timeout) +{ + struct nct6694_wdt_data *data = watchdog_get_drvdata(wdev); + int ret; + + if (timeout < wdev->pretimeout) { + dev_warn(data->dev, "pretimeout < timeout. Setting to zero\n"); + wdev->pretimeout = 0; + } + + ret = nct6694_wdt_setting(wdev, timeout, NCT6694_ACTION_GPO, + wdev->pretimeout, NCT6694_ACTION_GPO); + if (ret) + return ret; + + wdev->timeout = timeout; + + return ret; +} + +static int nct6694_wdt_set_pretimeout(struct watchdog_device *wdev, + unsigned int pretimeout) +{ + int ret; + + ret = nct6694_wdt_setting(wdev, wdev->timeout, NCT6694_ACTION_GPO, + pretimeout, NCT6694_ACTION_GPO); + if (ret) + return ret; + + wdev->pretimeout = pretimeout; + + return ret; +} + +static unsigned int nct6694_wdt_get_time(struct watchdog_device *wdev) +{ + struct nct6694_wdt_data *data = watchdog_get_drvdata(wdev); + struct nct6694_wdt_cmd0 *buf = (struct nct6694_wdt_cmd0 *)data->xmit_buf; + struct nct6694 *nct6694 = data->nct6694; + unsigned int timeleft_ms; + int ret; + + guard(mutex)(&data->lock); + + ret = nct6694_read_msg(nct6694, NCT6694_WDT_MOD, + NCT6694_WDT_CMD0_OFFSET(data->wdev_idx), + NCT6694_WDT_CMD0_LEN, buf); + if (ret) + return ret; + + timeleft_ms = le32_to_cpu(buf->countdown); + + return timeleft_ms / 1000; +} + +static const struct watchdog_info nct6694_wdt_info = { + .options = WDIOF_SETTIMEOUT | + WDIOF_KEEPALIVEPING | + WDIOF_MAGICCLOSE | + WDIOF_PRETIMEOUT, + .identity = DRVNAME, +}; + +static const struct watchdog_ops nct6694_wdt_ops = { + .owner = THIS_MODULE, + .start = nct6694_wdt_start, + .stop = nct6694_wdt_stop, + .set_timeout = nct6694_wdt_set_timeout, + .set_pretimeout = nct6694_wdt_set_pretimeout, + .get_timeleft = nct6694_wdt_get_time, + .ping = nct6694_wdt_ping, +}; + +static int nct6694_wdt_probe(struct platform_device *pdev) +{ + const struct mfd_cell *cell = mfd_get_cell(pdev); + struct device *dev = &pdev->dev; + struct nct6694 *nct6694 = dev_get_drvdata(pdev->dev.parent); + struct nct6694_wdt_data *data; + struct watchdog_device *wdev; + + data = devm_kzalloc(&pdev->dev, sizeof(*data), GFP_KERNEL); + if (!data) + return -ENOMEM; + + data->xmit_buf = devm_kcalloc(dev, NCT6694_MAX_PACKET_SZ, + sizeof(unsigned char), GFP_KERNEL); + if (!data->xmit_buf) + return -ENOMEM; + + data->dev = dev; + data->nct6694 = nct6694; + data->wdev_idx = cell->id; + + wdev = &data->wdev; + wdev->info = &nct6694_wdt_info; + wdev->ops = &nct6694_wdt_ops; + wdev->timeout = timeout; + wdev->pretimeout = pretimeout; + wdev->min_timeout = 1; + wdev->max_timeout = 255; + + mutex_init(&data->lock); + + platform_set_drvdata(pdev, data); + + /* Register watchdog timer device to WDT framework */ + watchdog_set_drvdata(&data->wdev, data); + watchdog_init_timeout(&data->wdev, timeout, dev); + watchdog_set_nowayout(&data->wdev, nowayout); + watchdog_stop_on_reboot(&data->wdev); + + return devm_watchdog_register_device(dev, &data->wdev); +} + +static struct platform_driver nct6694_wdt_driver = { + .driver = { + .name = DRVNAME, + }, + .probe = nct6694_wdt_probe, +}; + +module_platform_driver(nct6694_wdt_driver); + +MODULE_DESCRIPTION("USB-WDT driver for NCT6694"); +MODULE_AUTHOR("Ming Yu <tmyu0@nuvoton.com>"); +MODULE_LICENSE("GPL");
This driver supports Watchdog timer functionality for NCT6694 MFD device based on USB interface. Signed-off-by: Ming Yu <tmyu0@nuvoton.com> --- MAINTAINERS | 1 + drivers/watchdog/Kconfig | 11 ++ drivers/watchdog/Makefile | 1 + drivers/watchdog/nct6694_wdt.c | 277 +++++++++++++++++++++++++++++++++ 4 files changed, 290 insertions(+) create mode 100644 drivers/watchdog/nct6694_wdt.c