[PATCH] Watchdog: New module for ITE 5632 watchdog

From: David Ober
Date: Thu Jul 13 2023 - 06:58:45 EST


This modules is to allow for the new ITE 5632 EC chip
to support the watchdog for initial use in the Lenovo SE10

Signed-off-by: David Ober <dober6023@xxxxxxxxx>
---
drivers/watchdog/Kconfig | 10 ++
drivers/watchdog/Makefile | 1 +
drivers/watchdog/ite5632_wdt.c | 279 +++++++++++++++++++++++++++++++++
3 files changed, 290 insertions(+)
create mode 100644 drivers/watchdog/ite5632_wdt.c

diff --git a/drivers/watchdog/Kconfig b/drivers/watchdog/Kconfig
index ee97d89dfc11..861cc0eff468 100644
--- a/drivers/watchdog/Kconfig
+++ b/drivers/watchdog/Kconfig
@@ -264,6 +264,16 @@ config MENZ069_WATCHDOG
This driver can also be built as a module. If so the module
will be called menz069_wdt.

+config ITE5632_WDT
+ tristate "ITE 5632"
+ select WATCHDOG_CORE
+ help
+ If you say yes here you get support for the watchdog
+ functionality of the ITE 5632 eSIO chip.
+
+ This driver can also be built as a module. If so, the module
+ will be called ite5632_wdt.
+
config WDAT_WDT
tristate "ACPI Watchdog Action Table (WDAT)"
depends on ACPI
diff --git a/drivers/watchdog/Makefile b/drivers/watchdog/Makefile
index 3633f5b98236..32c8340f3175 100644
--- a/drivers/watchdog/Makefile
+++ b/drivers/watchdog/Makefile
@@ -119,6 +119,7 @@ obj-$(CONFIG_WAFER_WDT) += wafer5823wdt.o
obj-$(CONFIG_I6300ESB_WDT) += i6300esb.o
obj-$(CONFIG_IE6XX_WDT) += ie6xx_wdt.o
obj-$(CONFIG_ITCO_WDT) += iTCO_wdt.o
+obj-$(CONFIG_ITE5632_WDT) += ite5632_wdt.o
ifeq ($(CONFIG_ITCO_VENDOR_SUPPORT),y)
obj-$(CONFIG_ITCO_WDT) += iTCO_vendor_support.o
endif
diff --git a/drivers/watchdog/ite5632_wdt.c b/drivers/watchdog/ite5632_wdt.c
new file mode 100644
index 000000000000..32a68f16674f
--- /dev/null
+++ b/drivers/watchdog/ite5632_wdt.c
@@ -0,0 +1,279 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
+/*
+ * Customized ITE5632 WDT driver for Lenovo SE10.
+ *
+ */
+
+#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
+
+#include <linux/delay.h>
+#include <linux/init.h>
+#include <linux/io.h>
+#include <linux/ioport.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 EC_STATUS_port 0x6C
+#define EC_CMD_port 0x6C
+#define EC_DATA_port 0x68
+#define EC_OBF 0x01
+#define EC_IBF 0x02
+#define CFG_LDN 0x07
+#define CFG_BRAM_LDN 0x10 /* for BRAM Base */
+#define CFG_PORT 0x2E
+
+#define CUS_WDT_SWI 0x1A
+#define CUS_WDT_CFG 0x1B
+#define CUS_WDT_FEED 0xB0
+#define CUS_WDT_CNT 0xB1
+
+#define DRVNAME "ite5632"
+
+/*The timeout range is 1-255 seconds*/
+#define MIN_TIMEOUT 1
+#define MAX_TIMEOUT 255
+
+#define WATCHDOG_TIMEOUT 60 /* 60 sec default timeout */
+static unsigned short bram_base;
+
+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 ite5632_data_t {
+ struct watchdog_device wdt;
+};
+
+/* Kernel methods. */
+static void set_bram(unsigned char offset, unsigned char val)
+{
+ outb(offset, bram_base);
+ outb(val, bram_base + 1);
+}
+
+/* wait EC output buffer full */
+static void wait_EC_OBF(void)
+{
+ while (1) {
+ if (inb(EC_STATUS_port) & EC_OBF)
+ break;
+ udelay(10);
+ }
+}
+
+/* wait EC input buffer empty */
+static void wait_EC_IBE(void)
+{
+ while (1) {
+ if (!(inb(EC_STATUS_port) & EC_IBF))
+ break;
+ udelay(10);
+ }
+}
+
+static void send_EC_cmd(unsigned char EcCmd)
+{
+ wait_EC_IBE();
+ outb(EcCmd, EC_CMD_port);
+ wait_EC_IBE();
+}
+
+static unsigned char Read_EC_data(void)
+{
+ wait_EC_OBF();
+ return inb(EC_DATA_port);
+}
+
+static void LPC_Write_Byte(unsigned char index, unsigned char data)
+{
+ outb(index, CFG_PORT);
+ outb(data, CFG_PORT + 1);
+}
+
+static unsigned char LPC_Read_Byte(unsigned char index)
+{
+ outb(index, CFG_PORT);
+ return inb(CFG_PORT + 1);
+}
+
+static int GetChipID(void)
+{
+ unsigned short wPortAddr = 0x2E;
+ unsigned char MSB, LSB;
+ unsigned char cmd = (CFG_PORT == 0x2E) ? (0x55) : (0xAA);
+
+ outb(0x87, CFG_PORT);
+ outb(0x01, CFG_PORT);
+ outb(0x55, CFG_PORT);
+ outb(cmd, CFG_PORT);
+ outb(0x20, wPortAddr);
+ MSB = inb(wPortAddr + 1);
+ outb(0x21, wPortAddr);
+ LSB = inb(wPortAddr + 1);
+ return (MSB * 256 + LSB);
+}
+
+static int wdt_start(struct watchdog_device *wdog)
+{
+ set_bram(CUS_WDT_SWI, 0x80);
+ return 0;
+}
+
+static int wdt_set_timeout(struct watchdog_device *wdog, unsigned int timeout)
+{
+ wdog->timeout = timeout;
+ set_bram(CUS_WDT_CFG, wdog->timeout);
+ return 0;
+}
+
+static int wdt_stop(struct watchdog_device *wdog)
+{
+ wdt_set_timeout(wdog, 0);
+ return 0;
+}
+
+static unsigned int wdt_get_time(struct watchdog_device *wdog)
+{
+ unsigned int timeleft;
+ struct ite5632_data_t *data = watchdog_get_drvdata(wdog);
+
+ if (!request_region(EC_DATA_port, 5, "EC")) {
+ dev_err(data->wdt.parent, ":request fail\n");
+ return 0;
+ }
+ send_EC_cmd(CUS_WDT_CNT);
+
+ timeleft = (int)Read_EC_data();
+ release_region(EC_DATA_port, 5);
+ return timeleft;
+}
+
+static int wdt_ping(struct watchdog_device *wdog)
+{
+ struct ite5632_data_t *data = watchdog_get_drvdata(wdog);
+
+ if (!request_region(EC_DATA_port, 5, "EC")) {
+ dev_err(data->wdt.parent, ":request fail\n");
+ return 0;
+ }
+ send_EC_cmd(CUS_WDT_FEED);
+ release_region(EC_DATA_port, 5);
+ return 0;
+}
+
+/* Kernel Interfaces */
+static const struct watchdog_info wdt_info = {
+ .options = WDIOF_SETTIMEOUT | WDIOF_KEEPALIVEPING | WDIOF_MAGICCLOSE,
+ .identity = "5632 Watchdog",
+};
+
+static const struct watchdog_ops 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 int ite5632_probe(struct platform_device *pdev)
+{
+ struct device *dev = &pdev->dev;
+ struct ite5632_data_t *data = NULL;
+
+ dev_info(&pdev->dev, "Probe ITE5632 called\n");
+
+ data = devm_kzalloc(&pdev->dev, sizeof(*data), GFP_KERNEL);
+ if (!data)
+ return -ENOMEM;
+
+ data->wdt.info = &wdt_info,
+ data->wdt.ops = &wdt_ops,
+ data->wdt.timeout = WATCHDOG_TIMEOUT; /* Set default timeout */
+ data->wdt.min_timeout = MIN_TIMEOUT;
+ data->wdt.max_timeout = MAX_TIMEOUT;
+ data->wdt.parent = &pdev->dev;
+
+ watchdog_init_timeout(&data->wdt, timeout, &pdev->dev);
+ watchdog_set_drvdata(&data->wdt, data);
+
+ watchdog_set_nowayout(&data->wdt, nowayout);
+ watchdog_stop_on_reboot(&data->wdt);
+ watchdog_stop_on_unregister(&data->wdt);
+
+ dev_info(&pdev->dev, "initialized. timeout=%d sec (nowayout=%d)\n",
+ data->wdt.timeout, nowayout);
+
+ return devm_watchdog_register_device(dev, &data->wdt);
+}
+
+static struct platform_driver ite5632_driver = {
+ .driver = {
+ .name = DRVNAME,
+ },
+ .probe = ite5632_probe,
+};
+
+static struct platform_device *pdev;
+
+static int __init wdt_init(void)
+{
+ int ret;
+ int chip;
+
+ chip = GetChipID();
+
+ if (chip == 0x5632)
+ pr_info("Found ITE ChipID= %4X\n", chip);
+ else {
+ pr_info("ITE ChipID 5632 not found\n");
+ return -ENODEV;
+ }
+
+ LPC_Write_Byte(CFG_LDN, CFG_BRAM_LDN);
+ bram_base = ((LPC_Read_Byte(0x60) << 8) | LPC_Read_Byte(0x61));
+
+ platform_driver_register(&ite5632_driver);
+
+ pdev = platform_device_alloc(DRVNAME, bram_base);
+
+ dev_info(&pdev->dev, "ITE5632 device found\n");
+
+ /* platform_device_add calls probe() */
+ ret = platform_device_add(pdev);
+ if (ret) {
+ platform_device_put(pdev);
+ if (pdev)
+ platform_device_unregister(pdev);
+ platform_driver_unregister(&ite5632_driver);
+ }
+ return ret;
+}
+
+static void __exit wdt_exit(void)
+{
+ platform_device_unregister(pdev);
+ platform_driver_unregister(&ite5632_driver);
+
+ outb(0x02, 0x2E);
+ outb(0x02, 0x2E + 1);
+}
+
+module_init(wdt_init);
+module_exit(wdt_exit);
+
+MODULE_LICENSE("GPL");
+MODULE_AUTHOR("David Ober<dober@xxxxxxxxxx>");
+MODULE_DESCRIPTION("WDT driver for ITE5632");
--
2.34.1