MAX6370 watchdog is available e.g. on Freescale P1/P2 RDB-PC boards.
Signed-off-by: Pali Rohár pali@kernel.org --- drivers/watchdog/Kconfig | 7 ++ drivers/watchdog/Makefile | 1 + drivers/watchdog/max6370_wdt.c | 119 +++++++++++++++++++++++++++++++++ 3 files changed, 127 insertions(+) create mode 100644 drivers/watchdog/max6370_wdt.c
diff --git a/drivers/watchdog/Kconfig b/drivers/watchdog/Kconfig index f90f0ca02bce..1801698ac512 100644 --- a/drivers/watchdog/Kconfig +++ b/drivers/watchdog/Kconfig @@ -167,6 +167,13 @@ config WDT_GPIO doc/device-tree-bindings/watchdog/gpio-wdt.txt for information on how to describe the watchdog in device tree.
+config WDT_MAX6370 + bool "MAX6370 watchdog timer support" + depends on WDT + select DM_GPIO + help + Select this to enable max6370 watchdog timer. + config WDT_MPC8xx bool "MPC8xx watchdog timer support" depends on WDT && MPC8xx diff --git a/drivers/watchdog/Makefile b/drivers/watchdog/Makefile index a35bd559f51b..f999e4126b4f 100644 --- a/drivers/watchdog/Makefile +++ b/drivers/watchdog/Makefile @@ -27,6 +27,7 @@ obj-$(CONFIG_WDT_CORTINA) += cortina_wdt.o obj-$(CONFIG_WDT_ORION) += orion_wdt.o obj-$(CONFIG_WDT_CDNS) += cdns_wdt.o obj-$(CONFIG_WDT_GPIO) += gpio_wdt.o +obj-$(CONFIG_WDT_MAX6370) += max6370_wdt.o obj-$(CONFIG_WDT_MPC8xx) += mpc8xx_wdt.o obj-$(CONFIG_WDT_MT7620) += mt7620_wdt.o obj-$(CONFIG_WDT_MT7621) += mt7621_wdt.o diff --git a/drivers/watchdog/max6370_wdt.c b/drivers/watchdog/max6370_wdt.c new file mode 100644 index 000000000000..556c6a4b6d6b --- /dev/null +++ b/drivers/watchdog/max6370_wdt.c @@ -0,0 +1,119 @@ +// SPDX-License-Identifier: GPL-2.0+ +// (C) 2022 Pali Rohár pali@kernel.org + +#include <common.h> +#include <asm/io.h> +#include <asm-generic/gpio.h> +#include <dm.h> +#include <linux/delay.h> +#include <wdt.h> + +#define MAX6370_SET_MASK 0x7 +#define MAX6370_SET_1MS 0x0 +#define MAX6370_SET_10MS 0x1 +#define MAX6370_SET_30MS 0x2 +#define MAX6370_SET_DISABLE 0x3 +#define MAX6370_SET_100MS 0x4 +#define MAX6370_SET_1S 0x5 +#define MAX6370_SET_10S 0x6 +#define MAX6370_SET_60S 0x7 + +#define MAX6370_WDI 0x8 + +struct max6370_wdt { + void __iomem *reg; + struct gpio_desc gpio_wdi; +}; + +static int max6370_wdt_start(struct udevice *dev, u64 ms, ulong flags) +{ + struct max6370_wdt *wdt = dev_get_priv(dev); + u8 val; + + val = readb(wdt->reg); + val &= ~MAX6370_SET_MASK; + + if (ms <= 1) + val |= MAX6370_SET_1MS; + else if (ms <= 10) + val |= MAX6370_SET_10MS; + else if (ms <= 30) + val |= MAX6370_SET_30MS; + else if (ms <= 100) + val |= MAX6370_SET_100MS; + else if (ms <= 1000) + val |= MAX6370_SET_1S; + else if (ms <= 10000) + val |= MAX6370_SET_10S; + else + val |= MAX6370_SET_60S; + + writeb(val, wdt->reg); + + return 0; +} + +static int max6370_wdt_stop(struct udevice *dev) +{ + struct max6370_wdt *wdt = dev_get_priv(dev); + u8 val; + + val = readb(wdt->reg); + val &= ~MAX6370_SET_MASK; + val |= MAX6370_SET_DISABLE; + writeb(val, wdt->reg); + + return 0; +} + +static int max6370_wdt_reset(struct udevice *dev) +{ + struct max6370_wdt *wdt = dev_get_priv(dev); + u8 val; + + if (dm_gpio_is_valid(&wdt->gpio_wdi)) { + dm_gpio_set_value(&wdt->gpio_wdi, 1); + udelay(1); + dm_gpio_set_value(&wdt->gpio_wdi, 0); + } else { + val = readb(wdt->reg); + writeb(val | MAX6370_WDI, wdt->reg); + writeb(val & ~MAX6370_WDI, wdt->reg); + } + + return 0; +} + +static int max6370_wdt_probe(struct udevice *dev) +{ + struct max6370_wdt *wdt = dev_get_priv(dev); + + wdt->reg = dev_read_addr_ptr(dev); + if (!wdt->reg) + return -EINVAL; + + /* WDI gpio is optional */ + gpio_request_by_name(dev, "gpios", 0, &wdt->gpio_wdi, GPIOD_IS_OUT); + + return 0; +} + +static const struct wdt_ops max6370_wdt_ops = { + .start = max6370_wdt_start, + .stop = max6370_wdt_stop, + .reset = max6370_wdt_reset, +}; + +static const struct udevice_id max6370_wdt_ids[] = { + { .compatible = "maxim,max6370" }, + {} +}; + +U_BOOT_DRIVER(max6370_wdt) = { + .name = "max6370_wdt", + .id = UCLASS_WDT, + .of_match = max6370_wdt_ids, + .probe = max6370_wdt_probe, + .priv_auto = sizeof(struct max6370_wdt), + .ops = &max6370_wdt_ops, +};