Message ID | 20240503-congatec-board-controller-v1-4-fec5236270e7@bootlin.com (mailing list archive) |
---|---|
State | New |
Headers | show |
Series | Congatec Board Controller drivers | expand |
On Fri, Aug 09, 2024 at 04:52:08PM +0200, Thomas Richard wrote: > Add watchdog timer support for the Congatec Board Controller. > > Signed-off-by: Thomas Richard <thomas.richard@bootlin.com> > --- > drivers/watchdog/Kconfig | 10 ++ > drivers/watchdog/Makefile | 1 + > drivers/watchdog/cgbc_wdt.c | 217 ++++++++++++++++++++++++++++++++++++++++++++ > 3 files changed, 228 insertions(+) > > diff --git a/drivers/watchdog/Kconfig b/drivers/watchdog/Kconfig > index bae1d97cce89..07b711fc8bb2 100644 > --- a/drivers/watchdog/Kconfig > +++ b/drivers/watchdog/Kconfig > @@ -1142,6 +1142,16 @@ config ALIM7101_WDT > > Most people will say N. > > +config CGBC_WDT > + tristate "Congatec Board Controller Watchdog Timer" > + depends on MFD_CGBC > + select WATCHDOG_CORE > + help > + Enables watchdog timer support for the Congatec Board Controller. > + > + This driver can also be built as a module. If so, the module will be > + called cgbc_wdt. > + > config EBC_C384_WDT > tristate "WinSystems EBC-C384 Watchdog Timer" > depends on (X86 || COMPILE_TEST) && HAS_IOPORT > diff --git a/drivers/watchdog/Makefile b/drivers/watchdog/Makefile > index b51030f035a6..5aa66ba91346 100644 > --- a/drivers/watchdog/Makefile > +++ b/drivers/watchdog/Makefile > @@ -106,6 +106,7 @@ obj-$(CONFIG_ADVANTECH_WDT) += advantechwdt.o > obj-$(CONFIG_ADVANTECH_EC_WDT) += advantech_ec_wdt.o > obj-$(CONFIG_ALIM1535_WDT) += alim1535_wdt.o > obj-$(CONFIG_ALIM7101_WDT) += alim7101_wdt.o > +obj-$(CONFIG_CGBC_WDT) += cgbc_wdt.o > obj-$(CONFIG_EBC_C384_WDT) += ebc-c384_wdt.o > obj-$(CONFIG_EXAR_WDT) += exar_wdt.o > obj-$(CONFIG_F71808E_WDT) += f71808e_wdt.o > diff --git a/drivers/watchdog/cgbc_wdt.c b/drivers/watchdog/cgbc_wdt.c > new file mode 100644 > index 000000000000..9327e87b52e8 > --- /dev/null > +++ b/drivers/watchdog/cgbc_wdt.c > @@ -0,0 +1,217 @@ > +// SPDX-License-Identifier: GPL-2.0-or-later > +/* > + * Congatec Board Controller watchdog driver > + * > + * Copyright (C) 2024 Bootlin > + * Author: Thomas Richard <thomas.richard@bootlin.com> > + */ > + > +#include <linux/module.h> > +#include <linux/platform_device.h> > +#include <linux/watchdog.h> > + > +#include <linux/mfd/cgbc.h> > + > +#define CGBC_WDT_CMD_TRIGGER 0x27 > +#define CGBC_WDT_CMD_INIT 0x28 > +#define CGBC_WDT_DISABLE 0x00 > + > +#define CGBC_WDT_MODE_SINGLE_EVENT 0x02 > + > +#define DEFAULT_TIMEOUT_SEC 30 > +#define DEFAULT_PRETIMEOUT_SEC 0 > + > +enum action { > + ACTION_INT = 0, > + ACTION_SMI, > + ACTION_RESET, > + ACTION_BUTTON, > +}; > + > +static unsigned int timeout = DEFAULT_TIMEOUT_SEC; > +module_param(timeout, uint, 0); > +MODULE_PARM_DESC(timeout, > + "Watchdog timeout in seconds. (>=0, default=" > + __MODULE_STRING(DEFAULT_TIMEOUT_SEC) ")"); > + > +static unsigned int pretimeout = DEFAULT_PRETIMEOUT_SEC; > +module_param(pretimeout, uint, 0); > +MODULE_PARM_DESC(pretimeout, > + "Watchdog pretimeout in seconds. (>=0, default=" > + __MODULE_STRING(DEFAULT_PRETIMEOUT_SEC) ")"); > + > +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) ")"); > + > +struct cgbc_wdt_data { > + struct cgbc_device_data *cgbc; > + struct watchdog_device wdd; > + enum action timeout_action; > + enum action pretimeout_action; > +}; > + > +struct cgbc_wdt_cmd_cfg { > + u8 cmd; > + u8 mode; > + u8 action; > + u8 timeout1[3]; > + u8 timeout2[3]; > + u8 reserved[3]; > + u8 delay[3]; > +} __packed; > + > +static_assert(sizeof(struct cgbc_wdt_cmd_cfg) == 15); static_assert() is declared in linux/build_bug.h. Please include all necessary include files explicitly and do not depend on indirect includes. > + > +static int cgbc_wdt_start(struct watchdog_device *wdd) > +{ > + struct cgbc_wdt_data *wdt_data = watchdog_get_drvdata(wdd); Unusual way to get wdt_data instead of using container_of(). Any special reason ? > + struct cgbc_device_data *cgbc = wdt_data->cgbc; > + unsigned int timeout1 = (wdd->timeout - wdd->pretimeout) * 1000; > + unsigned int timeout2 = wdd->pretimeout * 1000; > + u8 action; > + > + struct cgbc_wdt_cmd_cfg cmd_start = { > + .cmd = CGBC_WDT_CMD_INIT, > + .mode = CGBC_WDT_MODE_SINGLE_EVENT, > + .timeout1[0] = (u8)timeout1, > + .timeout1[1] = (u8)(timeout1 >> 8), > + .timeout1[2] = (u8)(timeout1 >> 16), > + .timeout2[0] = (u8)timeout2, > + .timeout2[1] = (u8)(timeout2 >> 8), > + .timeout2[2] = (u8)(timeout2 >> 16), > + }; > + > + if (wdd->pretimeout) { > + action = 2; > + action |= wdt_data->pretimeout_action << 2; > + action |= wdt_data->timeout_action << 4; > + } else { > + action = 1; > + action |= wdt_data->timeout_action << 2; > + } > + > + cmd_start.action = action; > + > + return cgbc_command(cgbc, &cmd_start, sizeof(cmd_start), NULL, 0, NULL); > +} > + > +static int cgbc_wdt_stop(struct watchdog_device *wdd) > +{ > + struct cgbc_wdt_data *wdt_data = watchdog_get_drvdata(wdd); > + struct cgbc_device_data *cgbc = wdt_data->cgbc; > + struct cgbc_wdt_cmd_cfg cmd_stop = { > + .cmd = CGBC_WDT_CMD_INIT, > + .mode = CGBC_WDT_DISABLE, > + }; > + > + return cgbc_command(cgbc, &cmd_stop, sizeof(cmd_stop), NULL, 0, NULL); > +} > + > +static int cgbc_wdt_keepalive(struct watchdog_device *wdd) > +{ > + struct cgbc_wdt_data *wdt_data = watchdog_get_drvdata(wdd); > + struct cgbc_device_data *cgbc = wdt_data->cgbc; > + u8 cmd_ping = CGBC_WDT_CMD_TRIGGER; > + > + return cgbc_command(cgbc, &cmd_ping, sizeof(cmd_ping), NULL, 0, NULL); > +} > + > +static int cgbc_wdt_set_pretimeout(struct watchdog_device *wdd, > + unsigned int pretimeout) > +{ > + struct cgbc_wdt_data *wdt_data = watchdog_get_drvdata(wdd); > + > + wdd->pretimeout = pretimeout; > + wdt_data->pretimeout_action = ACTION_SMI; > + > + if (watchdog_active(wdd)) > + return cgbc_wdt_start(wdd); > + > + return 0; > +} > + > +static int cgbc_wdt_set_timeout(struct watchdog_device *wdd, > + unsigned int timeout) > +{ > + struct cgbc_wdt_data *wdt_data = watchdog_get_drvdata(wdd); > + > + if (timeout < wdd->pretimeout) { > + dev_warn(wdd->parent, "timeout <= pretimeout. Setting pretimeout to zero\n"); That is a normal condition which does not warrant a log message. Also see drivers/watchdog/watchdog_dev.c around line 385. > + wdd->pretimeout = 0; > + } > + > + wdd->timeout = timeout; > + wdt_data->timeout_action = ACTION_RESET; Both timeout_action and pretimeout_action are set statically. What is the point of doing that instead of just using ACTION_RESET and ACTION_SMI as needed irectly ? > + > + if (watchdog_active(wdd)) > + return cgbc_wdt_start(wdd); > + > + return 0; > +} > + > +static const struct watchdog_info cgbc_wdt_info = { > + .identity = "CGBC Watchdog", > + .options = WDIOF_SETTIMEOUT | WDIOF_KEEPALIVEPING | > + WDIOF_MAGICCLOSE | WDIOF_PRETIMEOUT > +}; > + > +static const struct watchdog_ops cgbc_wdt_ops = { > + .owner = THIS_MODULE, > + .start = cgbc_wdt_start, > + .stop = cgbc_wdt_stop, > + .ping = cgbc_wdt_keepalive, > + .set_timeout = cgbc_wdt_set_timeout, > + .set_pretimeout = cgbc_wdt_set_pretimeout, > +}; > + > +static int cgbc_wdt_probe(struct platform_device *pdev) > +{ > + struct cgbc_device_data *cgbc = dev_get_drvdata(pdev->dev.parent); > + struct device *dev = &pdev->dev; > + struct cgbc_wdt_data *wdt_data; > + struct watchdog_device *wdd; > + int ret; > + > + wdt_data = devm_kzalloc(dev, sizeof(*wdt_data), GFP_KERNEL); devm_kzalloc() is declared in linux/device.h. Again, please include all necessary include files explicitly. > + if (!wdt_data) > + return -ENOMEM; > + > + wdt_data->cgbc = cgbc; > + wdd = &wdt_data->wdd; > + wdd->parent = dev; > + No limits ? That is unusual. Are you sure the driver accepts all timeouts from 0 to UINT_MAX ? > + wdd->info = &cgbc_wdt_info; > + wdd->ops = &cgbc_wdt_ops; > + > + watchdog_set_drvdata(wdd, wdt_data); > + watchdog_set_nowayout(wdd, nowayout); > + > + cgbc_wdt_set_timeout(wdd, timeout); > + cgbc_wdt_set_pretimeout(wdd, pretimeout); The more common approach would be to set default limits in wdd->{timout,pretimeout} and only override the values if needed, ie if provided using module parameters. That implies initializing the module parameters with 0. YOur call, though. > + > + platform_set_drvdata(pdev, wdt_data); > + watchdog_stop_on_reboot(wdd); > + watchdog_stop_on_unregister(wdd); > + > + ret = devm_watchdog_register_device(dev, wdd); > + if (ret) > + return ret; > + > + return 0; Why not just return devm_watchdog_register_device(dev, wdd); ? > +} > + > +static struct platform_driver cgbc_wdt_driver = { > + .driver = { > + .name = "cgbc-wdt", > + }, > + .probe = cgbc_wdt_probe, > +}; > + > +module_platform_driver(cgbc_wdt_driver); > + > +MODULE_DESCRIPTION("Congatec Board Controller Watchdog Driver"); > +MODULE_AUTHOR("Thomas Richard <thomas.richard@bootlin.com>"); > +MODULE_LICENSE("GPL"); > > -- > 2.39.2 > >
Hi Guenter, >> + >> +struct cgbc_wdt_cmd_cfg { >> + u8 cmd; >> + u8 mode; >> + u8 action; >> + u8 timeout1[3]; >> + u8 timeout2[3]; >> + u8 reserved[3]; >> + u8 delay[3]; >> +} __packed; >> + >> +static_assert(sizeof(struct cgbc_wdt_cmd_cfg) == 15); > > static_assert() is declared in linux/build_bug.h. Please include all > necessary include files explicitly and do not depend on indirect includes. Fixed in next iteration. > >> + >> +static int cgbc_wdt_start(struct watchdog_device *wdd) >> +{ >> + struct cgbc_wdt_data *wdt_data = watchdog_get_drvdata(wdd); > > Unusual way to get wdt_data instead of using container_of(). > Any special reason ? No special reason, I saw that watchdog_get_drvdata() was often used in watchdog drivers (more than container_of()) to get wdt_data. But I can use container_of() if you think I should. > >> + struct cgbc_device_data *cgbc = wdt_data->cgbc; >> + unsigned int timeout1 = (wdd->timeout - wdd->pretimeout) * 1000; >> + unsigned int timeout2 = wdd->pretimeout * 1000; >> + u8 action; >> + >> + struct cgbc_wdt_cmd_cfg cmd_start = { >> + .cmd = CGBC_WDT_CMD_INIT, >> + .mode = CGBC_WDT_MODE_SINGLE_EVENT, >> + .timeout1[0] = (u8)timeout1, >> + .timeout1[1] = (u8)(timeout1 >> 8), >> + .timeout1[2] = (u8)(timeout1 >> 16), >> + .timeout2[0] = (u8)timeout2, >> + .timeout2[1] = (u8)(timeout2 >> 8), >> + .timeout2[2] = (u8)(timeout2 >> 16), >> + }; >> + >> + if (wdd->pretimeout) { >> + action = 2; >> + action |= wdt_data->pretimeout_action << 2; >> + action |= wdt_data->timeout_action << 4; >> + } else { >> + action = 1; >> + action |= wdt_data->timeout_action << 2; >> + } >> + >> + cmd_start.action = action; >> + >> + return cgbc_command(cgbc, &cmd_start, sizeof(cmd_start), NULL, 0, NULL); >> +} >> + >> +static int cgbc_wdt_stop(struct watchdog_device *wdd) >> +{ >> + struct cgbc_wdt_data *wdt_data = watchdog_get_drvdata(wdd); >> + struct cgbc_device_data *cgbc = wdt_data->cgbc; >> + struct cgbc_wdt_cmd_cfg cmd_stop = { >> + .cmd = CGBC_WDT_CMD_INIT, >> + .mode = CGBC_WDT_DISABLE, >> + }; >> + >> + return cgbc_command(cgbc, &cmd_stop, sizeof(cmd_stop), NULL, 0, NULL); >> +} >> + >> +static int cgbc_wdt_keepalive(struct watchdog_device *wdd) >> +{ >> + struct cgbc_wdt_data *wdt_data = watchdog_get_drvdata(wdd); >> + struct cgbc_device_data *cgbc = wdt_data->cgbc; >> + u8 cmd_ping = CGBC_WDT_CMD_TRIGGER; >> + >> + return cgbc_command(cgbc, &cmd_ping, sizeof(cmd_ping), NULL, 0, NULL); >> +} >> + >> +static int cgbc_wdt_set_pretimeout(struct watchdog_device *wdd, >> + unsigned int pretimeout) >> +{ >> + struct cgbc_wdt_data *wdt_data = watchdog_get_drvdata(wdd); >> + >> + wdd->pretimeout = pretimeout; >> + wdt_data->pretimeout_action = ACTION_SMI; >> + >> + if (watchdog_active(wdd)) >> + return cgbc_wdt_start(wdd); >> + >> + return 0; >> +} >> + >> +static int cgbc_wdt_set_timeout(struct watchdog_device *wdd, >> + unsigned int timeout) >> +{ >> + struct cgbc_wdt_data *wdt_data = watchdog_get_drvdata(wdd); >> + >> + if (timeout < wdd->pretimeout) { >> + dev_warn(wdd->parent, "timeout <= pretimeout. Setting pretimeout to zero\n"); > > That is a normal condition which does not warrant a log message. > Also see drivers/watchdog/watchdog_dev.c around line 385. Fixed in next iteration. > >> + wdd->pretimeout = 0; >> + } >> + >> + wdd->timeout = timeout; >> + wdt_data->timeout_action = ACTION_RESET; > > Both timeout_action and pretimeout_action are set statically. > What is the point of doing that instead of just using > ACTION_RESET and ACTION_SMI as needed irectly ? Yes indeed, using ACTION_RESET and ACTION_SMI directly in cgbc_wdt_start() makes the code smaller. > >> + >> + if (watchdog_active(wdd)) >> + return cgbc_wdt_start(wdd); >> + >> + return 0; >> +} >> + >> +static const struct watchdog_info cgbc_wdt_info = { >> + .identity = "CGBC Watchdog", >> + .options = WDIOF_SETTIMEOUT | WDIOF_KEEPALIVEPING | >> + WDIOF_MAGICCLOSE | WDIOF_PRETIMEOUT >> +}; >> + >> +static const struct watchdog_ops cgbc_wdt_ops = { >> + .owner = THIS_MODULE, >> + .start = cgbc_wdt_start, >> + .stop = cgbc_wdt_stop, >> + .ping = cgbc_wdt_keepalive, >> + .set_timeout = cgbc_wdt_set_timeout, >> + .set_pretimeout = cgbc_wdt_set_pretimeout, >> +}; >> + >> +static int cgbc_wdt_probe(struct platform_device *pdev) >> +{ >> + struct cgbc_device_data *cgbc = dev_get_drvdata(pdev->dev.parent); >> + struct device *dev = &pdev->dev; >> + struct cgbc_wdt_data *wdt_data; >> + struct watchdog_device *wdd; >> + int ret; >> + >> + wdt_data = devm_kzalloc(dev, sizeof(*wdt_data), GFP_KERNEL); > > devm_kzalloc() is declared in linux/device.h. Again, please include all > necessary include files explicitly. Fixed in next iteration. > >> + if (!wdt_data) >> + return -ENOMEM; >> + >> + wdt_data->cgbc = cgbc; >> + wdd = &wdt_data->wdd; >> + wdd->parent = dev; >> + > > No limits ? That is unusual. Are you sure the driver accepts all > timeouts from 0 to UINT_MAX ? Yes limits are needed. For next iteration I added 1s as min_timeout (which seems to be the usual value, and it is accepted by the hardware), and a max_timeout. > >> + wdd->info = &cgbc_wdt_info; >> + wdd->ops = &cgbc_wdt_ops; >> + >> + watchdog_set_drvdata(wdd, wdt_data); >> + watchdog_set_nowayout(wdd, nowayout); >> + >> + cgbc_wdt_set_timeout(wdd, timeout); >> + cgbc_wdt_set_pretimeout(wdd, pretimeout); > > The more common approach would be to set default limits in wdd->{timout,pretimeout} > and only override the values if needed, ie if provided using module parameters. > That implies initializing the module parameters with 0. YOur call, though. Ok. For next iteration I added limits (min_timeout, max_timeout), the timeout module parameter is set to 0 by default, and watchdog_init_timeout() is called in the probe. > >> + >> + platform_set_drvdata(pdev, wdt_data); >> + watchdog_stop_on_reboot(wdd); >> + watchdog_stop_on_unregister(wdd); >> + >> + ret = devm_watchdog_register_device(dev, wdd); >> + if (ret) >> + return ret; >> + >> + return 0; > > Why not just > return devm_watchdog_register_device(dev, wdd); > ? I don't know :) Fixed in the next iteration. Thanks for the review !! Thomas.
diff --git a/drivers/watchdog/Kconfig b/drivers/watchdog/Kconfig index bae1d97cce89..07b711fc8bb2 100644 --- a/drivers/watchdog/Kconfig +++ b/drivers/watchdog/Kconfig @@ -1142,6 +1142,16 @@ config ALIM7101_WDT Most people will say N. +config CGBC_WDT + tristate "Congatec Board Controller Watchdog Timer" + depends on MFD_CGBC + select WATCHDOG_CORE + help + Enables watchdog timer support for the Congatec Board Controller. + + This driver can also be built as a module. If so, the module will be + called cgbc_wdt. + config EBC_C384_WDT tristate "WinSystems EBC-C384 Watchdog Timer" depends on (X86 || COMPILE_TEST) && HAS_IOPORT diff --git a/drivers/watchdog/Makefile b/drivers/watchdog/Makefile index b51030f035a6..5aa66ba91346 100644 --- a/drivers/watchdog/Makefile +++ b/drivers/watchdog/Makefile @@ -106,6 +106,7 @@ obj-$(CONFIG_ADVANTECH_WDT) += advantechwdt.o obj-$(CONFIG_ADVANTECH_EC_WDT) += advantech_ec_wdt.o obj-$(CONFIG_ALIM1535_WDT) += alim1535_wdt.o obj-$(CONFIG_ALIM7101_WDT) += alim7101_wdt.o +obj-$(CONFIG_CGBC_WDT) += cgbc_wdt.o obj-$(CONFIG_EBC_C384_WDT) += ebc-c384_wdt.o obj-$(CONFIG_EXAR_WDT) += exar_wdt.o obj-$(CONFIG_F71808E_WDT) += f71808e_wdt.o diff --git a/drivers/watchdog/cgbc_wdt.c b/drivers/watchdog/cgbc_wdt.c new file mode 100644 index 000000000000..9327e87b52e8 --- /dev/null +++ b/drivers/watchdog/cgbc_wdt.c @@ -0,0 +1,217 @@ +// SPDX-License-Identifier: GPL-2.0-or-later +/* + * Congatec Board Controller watchdog driver + * + * Copyright (C) 2024 Bootlin + * Author: Thomas Richard <thomas.richard@bootlin.com> + */ + +#include <linux/module.h> +#include <linux/platform_device.h> +#include <linux/watchdog.h> + +#include <linux/mfd/cgbc.h> + +#define CGBC_WDT_CMD_TRIGGER 0x27 +#define CGBC_WDT_CMD_INIT 0x28 +#define CGBC_WDT_DISABLE 0x00 + +#define CGBC_WDT_MODE_SINGLE_EVENT 0x02 + +#define DEFAULT_TIMEOUT_SEC 30 +#define DEFAULT_PRETIMEOUT_SEC 0 + +enum action { + ACTION_INT = 0, + ACTION_SMI, + ACTION_RESET, + ACTION_BUTTON, +}; + +static unsigned int timeout = DEFAULT_TIMEOUT_SEC; +module_param(timeout, uint, 0); +MODULE_PARM_DESC(timeout, + "Watchdog timeout in seconds. (>=0, default=" + __MODULE_STRING(DEFAULT_TIMEOUT_SEC) ")"); + +static unsigned int pretimeout = DEFAULT_PRETIMEOUT_SEC; +module_param(pretimeout, uint, 0); +MODULE_PARM_DESC(pretimeout, + "Watchdog pretimeout in seconds. (>=0, default=" + __MODULE_STRING(DEFAULT_PRETIMEOUT_SEC) ")"); + +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) ")"); + +struct cgbc_wdt_data { + struct cgbc_device_data *cgbc; + struct watchdog_device wdd; + enum action timeout_action; + enum action pretimeout_action; +}; + +struct cgbc_wdt_cmd_cfg { + u8 cmd; + u8 mode; + u8 action; + u8 timeout1[3]; + u8 timeout2[3]; + u8 reserved[3]; + u8 delay[3]; +} __packed; + +static_assert(sizeof(struct cgbc_wdt_cmd_cfg) == 15); + +static int cgbc_wdt_start(struct watchdog_device *wdd) +{ + struct cgbc_wdt_data *wdt_data = watchdog_get_drvdata(wdd); + struct cgbc_device_data *cgbc = wdt_data->cgbc; + unsigned int timeout1 = (wdd->timeout - wdd->pretimeout) * 1000; + unsigned int timeout2 = wdd->pretimeout * 1000; + u8 action; + + struct cgbc_wdt_cmd_cfg cmd_start = { + .cmd = CGBC_WDT_CMD_INIT, + .mode = CGBC_WDT_MODE_SINGLE_EVENT, + .timeout1[0] = (u8)timeout1, + .timeout1[1] = (u8)(timeout1 >> 8), + .timeout1[2] = (u8)(timeout1 >> 16), + .timeout2[0] = (u8)timeout2, + .timeout2[1] = (u8)(timeout2 >> 8), + .timeout2[2] = (u8)(timeout2 >> 16), + }; + + if (wdd->pretimeout) { + action = 2; + action |= wdt_data->pretimeout_action << 2; + action |= wdt_data->timeout_action << 4; + } else { + action = 1; + action |= wdt_data->timeout_action << 2; + } + + cmd_start.action = action; + + return cgbc_command(cgbc, &cmd_start, sizeof(cmd_start), NULL, 0, NULL); +} + +static int cgbc_wdt_stop(struct watchdog_device *wdd) +{ + struct cgbc_wdt_data *wdt_data = watchdog_get_drvdata(wdd); + struct cgbc_device_data *cgbc = wdt_data->cgbc; + struct cgbc_wdt_cmd_cfg cmd_stop = { + .cmd = CGBC_WDT_CMD_INIT, + .mode = CGBC_WDT_DISABLE, + }; + + return cgbc_command(cgbc, &cmd_stop, sizeof(cmd_stop), NULL, 0, NULL); +} + +static int cgbc_wdt_keepalive(struct watchdog_device *wdd) +{ + struct cgbc_wdt_data *wdt_data = watchdog_get_drvdata(wdd); + struct cgbc_device_data *cgbc = wdt_data->cgbc; + u8 cmd_ping = CGBC_WDT_CMD_TRIGGER; + + return cgbc_command(cgbc, &cmd_ping, sizeof(cmd_ping), NULL, 0, NULL); +} + +static int cgbc_wdt_set_pretimeout(struct watchdog_device *wdd, + unsigned int pretimeout) +{ + struct cgbc_wdt_data *wdt_data = watchdog_get_drvdata(wdd); + + wdd->pretimeout = pretimeout; + wdt_data->pretimeout_action = ACTION_SMI; + + if (watchdog_active(wdd)) + return cgbc_wdt_start(wdd); + + return 0; +} + +static int cgbc_wdt_set_timeout(struct watchdog_device *wdd, + unsigned int timeout) +{ + struct cgbc_wdt_data *wdt_data = watchdog_get_drvdata(wdd); + + if (timeout < wdd->pretimeout) { + dev_warn(wdd->parent, "timeout <= pretimeout. Setting pretimeout to zero\n"); + wdd->pretimeout = 0; + } + + wdd->timeout = timeout; + wdt_data->timeout_action = ACTION_RESET; + + if (watchdog_active(wdd)) + return cgbc_wdt_start(wdd); + + return 0; +} + +static const struct watchdog_info cgbc_wdt_info = { + .identity = "CGBC Watchdog", + .options = WDIOF_SETTIMEOUT | WDIOF_KEEPALIVEPING | + WDIOF_MAGICCLOSE | WDIOF_PRETIMEOUT +}; + +static const struct watchdog_ops cgbc_wdt_ops = { + .owner = THIS_MODULE, + .start = cgbc_wdt_start, + .stop = cgbc_wdt_stop, + .ping = cgbc_wdt_keepalive, + .set_timeout = cgbc_wdt_set_timeout, + .set_pretimeout = cgbc_wdt_set_pretimeout, +}; + +static int cgbc_wdt_probe(struct platform_device *pdev) +{ + struct cgbc_device_data *cgbc = dev_get_drvdata(pdev->dev.parent); + struct device *dev = &pdev->dev; + struct cgbc_wdt_data *wdt_data; + struct watchdog_device *wdd; + int ret; + + wdt_data = devm_kzalloc(dev, sizeof(*wdt_data), GFP_KERNEL); + if (!wdt_data) + return -ENOMEM; + + wdt_data->cgbc = cgbc; + wdd = &wdt_data->wdd; + wdd->parent = dev; + + wdd->info = &cgbc_wdt_info; + wdd->ops = &cgbc_wdt_ops; + + watchdog_set_drvdata(wdd, wdt_data); + watchdog_set_nowayout(wdd, nowayout); + + cgbc_wdt_set_timeout(wdd, timeout); + cgbc_wdt_set_pretimeout(wdd, pretimeout); + + platform_set_drvdata(pdev, wdt_data); + watchdog_stop_on_reboot(wdd); + watchdog_stop_on_unregister(wdd); + + ret = devm_watchdog_register_device(dev, wdd); + if (ret) + return ret; + + return 0; +} + +static struct platform_driver cgbc_wdt_driver = { + .driver = { + .name = "cgbc-wdt", + }, + .probe = cgbc_wdt_probe, +}; + +module_platform_driver(cgbc_wdt_driver); + +MODULE_DESCRIPTION("Congatec Board Controller Watchdog Driver"); +MODULE_AUTHOR("Thomas Richard <thomas.richard@bootlin.com>"); +MODULE_LICENSE("GPL");
Add watchdog timer support for the Congatec Board Controller. Signed-off-by: Thomas Richard <thomas.richard@bootlin.com> --- drivers/watchdog/Kconfig | 10 ++ drivers/watchdog/Makefile | 1 + drivers/watchdog/cgbc_wdt.c | 217 ++++++++++++++++++++++++++++++++++++++++++++ 3 files changed, 228 insertions(+)