diff options
Diffstat (limited to 'drivers/watchdog/lenovo_se10_wdt.c')
| -rw-r--r-- | drivers/watchdog/lenovo_se10_wdt.c | 308 |
1 files changed, 308 insertions, 0 deletions
diff --git a/drivers/watchdog/lenovo_se10_wdt.c b/drivers/watchdog/lenovo_se10_wdt.c new file mode 100644 index 0000000000..139ff0e822 --- /dev/null +++ b/drivers/watchdog/lenovo_se10_wdt.c @@ -0,0 +1,308 @@ +// SPDX-License-Identifier: GPL-2.0-or-later +/* + * WDT driver for Lenovo SE10. + */ + +#include <linux/delay.h> +#include <linux/dmi.h> +#include <linux/io.h> +#include <linux/module.h> +#include <linux/moduleparam.h> +#include <linux/platform_device.h> +#include <linux/string.h> +#include <linux/types.h> +#include <linux/watchdog.h> + +#define STATUS_PORT 0x6C +#define CMD_PORT 0x6C +#define DATA_PORT 0x68 +#define OUTBUF_FULL 0x01 +#define INBUF_EMPTY 0x02 +#define CFG_LDN 0x07 +#define CFG_BRAM_LDN 0x10 /* for BRAM Base */ +#define CFG_PORT 0x2E +#define CFG_SIZE 2 +#define CMD_SIZE 4 +#define BRAM_SIZE 2 + +#define UNLOCK_KEY 0x87 +#define LOCK_KEY 0xAA + +#define CUS_WDT_SWI 0x1A +#define CUS_WDT_CFG 0x1B +#define CUS_WDT_FEED 0xB0 +#define CUS_WDT_CNT 0xB1 + +#define DRVNAME "lenovo-se10-wdt" + +/*The timeout range is 1-255 seconds*/ +#define MIN_TIMEOUT 1 +#define MAX_TIMEOUT 255 +#define MAX_WAIT 10 + +#define WATCHDOG_TIMEOUT 60 /* 60 sec default timeout */ +static unsigned short bram_base; +static struct platform_device *se10_pdev; + +static int timeout; /* in seconds */ +module_param(timeout, int, 0); +MODULE_PARM_DESC(timeout, + "Watchdog timeout in seconds. 1 <= timeout <= 255, default=" + __MODULE_STRING(WATCHDOG_TIMEOUT) "."); + +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 se10_wdt { + struct watchdog_device wdd; +}; + +static int set_bram(unsigned char offset, unsigned char val) +{ + if (!request_muxed_region(bram_base, BRAM_SIZE, DRVNAME)) + return -EBUSY; + outb(offset, bram_base); + outb(val, bram_base + 1); + release_region(bram_base, BRAM_SIZE); + return 0; +} + +static void wait_for_buffer(int condition) +{ + int loop = 0; + + while (1) { + if (inb(STATUS_PORT) & condition || loop > MAX_WAIT) + break; + loop++; + usleep_range(10, 125); + } +} + +static void send_cmd(unsigned char cmd) +{ + wait_for_buffer(INBUF_EMPTY); + outb(cmd, CMD_PORT); + wait_for_buffer(INBUF_EMPTY); +} + +static void lpc_write(unsigned char index, unsigned char data) +{ + outb(index, CFG_PORT); + outb(data, CFG_PORT + 1); +} + +static unsigned char lpc_read(unsigned char index) +{ + outb(index, CFG_PORT); + return inb(CFG_PORT + 1); +} + +static int wdt_start(struct watchdog_device *wdog) +{ + return set_bram(CUS_WDT_SWI, 0x80); +} + +static int wdt_set_timeout(struct watchdog_device *wdog, unsigned int timeout) +{ + wdog->timeout = timeout; + return set_bram(CUS_WDT_CFG, wdog->timeout); +} + +static int wdt_stop(struct watchdog_device *wdog) +{ + return set_bram(CUS_WDT_SWI, 0); +} + +static unsigned int wdt_get_time(struct watchdog_device *wdog) +{ + unsigned char time; + + if (!request_muxed_region(CMD_PORT, CMD_SIZE, DRVNAME)) + return -EBUSY; + send_cmd(CUS_WDT_CNT); + wait_for_buffer(OUTBUF_FULL); + time = inb(DATA_PORT); + release_region(CMD_PORT, CMD_SIZE); + return time; +} + +static int wdt_ping(struct watchdog_device *wdog) +{ + if (!request_muxed_region(CMD_PORT, CMD_SIZE, DRVNAME)) + return -EBUSY; + send_cmd(CUS_WDT_FEED); + release_region(CMD_PORT, CMD_SIZE); + return 0; +} + +static const struct watchdog_info wdt_info = { + .options = WDIOF_SETTIMEOUT | WDIOF_KEEPALIVEPING | WDIOF_MAGICCLOSE, + .identity = "Lenovo SE10 Watchdog", +}; + +static const struct watchdog_ops se10_wdt_ops = { + .owner = THIS_MODULE, + .start = wdt_start, + .stop = wdt_stop, + .ping = wdt_ping, + .set_timeout = wdt_set_timeout, + .get_timeleft = wdt_get_time, +}; + +static unsigned int get_chipID(void) +{ + unsigned char msb, lsb; + + outb(UNLOCK_KEY, CFG_PORT); + outb(0x01, CFG_PORT); + outb(0x55, CFG_PORT); + outb(0x55, CFG_PORT); + msb = lpc_read(0x20); + lsb = lpc_read(0x21); + outb(LOCK_KEY, CFG_PORT); + return (msb * 256 + lsb); +} + +static int se10_wdt_probe(struct platform_device *pdev) +{ + struct device *dev = &pdev->dev; + struct se10_wdt *priv; + unsigned int chip_id; + int ret; + + if (!request_muxed_region(CFG_PORT, CFG_SIZE, DRVNAME)) + return -EBUSY; + + chip_id = get_chipID(); + if (chip_id != 0x5632) { + release_region(CFG_PORT, CFG_SIZE); + return -ENODEV; + } + + lpc_write(CFG_LDN, CFG_BRAM_LDN); + bram_base = (lpc_read(0x60) << 8) | lpc_read(0x61); + release_region(CFG_PORT, CFG_SIZE); + + dev_info(dev, "Found Lenovo SE10 0x%x\n", chip_id); + + priv = devm_kzalloc(dev, sizeof(*priv), GFP_KERNEL); + if (!priv) + return -ENOMEM; + + watchdog_set_drvdata(&priv->wdd, priv); + + priv->wdd.parent = dev; + priv->wdd.info = &wdt_info, + priv->wdd.ops = &se10_wdt_ops, + priv->wdd.timeout = WATCHDOG_TIMEOUT; /* Set default timeout */ + priv->wdd.min_timeout = MIN_TIMEOUT; + priv->wdd.max_timeout = MAX_TIMEOUT; + + set_bram(CUS_WDT_CFG, WATCHDOG_TIMEOUT); /* Set time to default */ + + watchdog_init_timeout(&priv->wdd, timeout, dev); + watchdog_set_nowayout(&priv->wdd, nowayout); + watchdog_stop_on_reboot(&priv->wdd); + watchdog_stop_on_unregister(&priv->wdd); + + ret = devm_watchdog_register_device(dev, &priv->wdd); + + dev_dbg(&pdev->dev, "initialized. timeout=%d sec (nowayout=%d)\n", + priv->wdd.timeout, nowayout); + + return ret; +} + +static struct platform_driver se10_wdt_driver = { + .driver = { + .name = DRVNAME, + }, + .probe = se10_wdt_probe, +}; + +static int se10_create_platform_device(const struct dmi_system_id *id) +{ + int err; + + se10_pdev = platform_device_alloc("lenovo-se10-wdt", -1); + if (!se10_pdev) + return -ENOMEM; + + err = platform_device_add(se10_pdev); + if (err) + platform_device_put(se10_pdev); + + return err; +} + +static const struct dmi_system_id se10_dmi_table[] __initconst = { + { + .ident = "LENOVO-SE10", + .matches = { + DMI_MATCH(DMI_SYS_VENDOR, "LENOVO"), + DMI_MATCH(DMI_PRODUCT_NAME, "12NH"), + }, + .callback = se10_create_platform_device, + }, + { + .ident = "LENOVO-SE10", + .matches = { + DMI_MATCH(DMI_SYS_VENDOR, "LENOVO"), + DMI_MATCH(DMI_PRODUCT_NAME, "12NJ"), + }, + .callback = se10_create_platform_device, + }, + { + .ident = "LENOVO-SE10", + .matches = { + DMI_MATCH(DMI_SYS_VENDOR, "LENOVO"), + DMI_MATCH(DMI_PRODUCT_NAME, "12NK"), + }, + .callback = se10_create_platform_device, + }, + { + .ident = "LENOVO-SE10", + .matches = { + DMI_MATCH(DMI_SYS_VENDOR, "LENOVO"), + DMI_MATCH(DMI_PRODUCT_NAME, "12NL"), + }, + .callback = se10_create_platform_device, + }, + { + .ident = "LENOVO-SE10", + .matches = { + DMI_MATCH(DMI_SYS_VENDOR, "LENOVO"), + DMI_MATCH(DMI_PRODUCT_NAME, "12NM"), + }, + .callback = se10_create_platform_device, + }, + {} +}; +MODULE_DEVICE_TABLE(dmi, se10_dmi_table); + +static int __init se10_wdt_init(void) +{ + if (!dmi_check_system(se10_dmi_table)) + return -ENODEV; + + return platform_driver_register(&se10_wdt_driver); +} + +static void __exit se10_wdt_exit(void) +{ + if (se10_pdev) + platform_device_unregister(se10_pdev); + platform_driver_unregister(&se10_wdt_driver); +} + +module_init(se10_wdt_init); +module_exit(se10_wdt_exit); + +MODULE_LICENSE("GPL"); +MODULE_AUTHOR("David Ober<dober@lenovo.com>"); +MODULE_AUTHOR("Mark Pearson <mpearson-lenovo@squebb.ca>"); +MODULE_DESCRIPTION("WDT driver for Lenovo SE10"); |