lkml.org 
[lkml]   [2012]   [Feb]   [6]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
Patch in this message
/
Subject[PATCH 05/07] Watchdog: DA9052/53 watchdog support v1
From
Date
This driver adds support for the watchdog functionality provided by the
Dialog Semiconductor DA9052/53 PMIC chip.

This patch is functionally tested on Samsung SMDKV6410.

Signed-off-by: David Dajun Chen <dchen@diasemi.com>
Signed-off-by: Ashish Jangam <ashish.jangam@kpitcummins.com>
---
Documentation/watchdog/watchdog-parameters.txt | 5 +
drivers/watchdog/Kconfig | 6 +
drivers/watchdog/Makefile | 1 +
drivers/watchdog/da9052_wdt.c | 333 ++++++++++++++++++++++++
4 files changed, 345 insertions(+), 0 deletions(-)
create mode 100644 drivers/watchdog/da9052_wdt.c
diff --git a/Documentation/watchdog/watchdog-parameters.txt b/Documentation/watchdog/watchdog-parameters.txt
index 17ddd82..04fddba 100644
--- a/Documentation/watchdog/watchdog-parameters.txt
+++ b/Documentation/watchdog/watchdog-parameters.txt
@@ -78,6 +78,11 @@ wd0_timeout: Default watchdog0 timeout in 1/10secs
wd1_timeout: Default watchdog1 timeout in 1/10secs
wd2_timeout: Default watchdog2 timeout in 1/10secs
-------------------------------------------------
+da9052wdt:
+timeout: Watchdog timeout in seconds. 2<= timeout <=131, default=2.048s
+nowayout: Watchdog cannot be stopped once started
+ (default=kernel config parameter)
+-------------------------------------------------
davinci_wdt:
heartbeat: Watchdog heartbeat period in seconds from 1 to 600, default 60
-------------------------------------------------
diff --git a/drivers/watchdog/Kconfig b/drivers/watchdog/Kconfig
index 877b107..3fb9633 100644
--- a/drivers/watchdog/Kconfig
+++ b/drivers/watchdog/Kconfig
@@ -63,6 +63,12 @@ config SOFT_WATCHDOG
To compile this driver as a module, choose M here: the
module will be called softdog.

+config DA9052_WATCHDOG
+ tristate "Dialog DA9052/DA9053 Watchdog"
+ depends on PMIC_DA9052
+ help
+ Support for the watchdog in the DA9052-BC and DA9053-AA/Bx PMICs.
+
config WM831X_WATCHDOG
tristate "WM831x watchdog"
depends on MFD_WM831X
diff --git a/drivers/watchdog/Makefile b/drivers/watchdog/Makefile
index e8f479a..0ecbe5a 100644
--- a/drivers/watchdog/Makefile
+++ b/drivers/watchdog/Makefile
@@ -166,4 +166,5 @@ obj-$(CONFIG_XEN_WDT) += xen_wdt.o
obj-$(CONFIG_WM831X_WATCHDOG) += wm831x_wdt.o
obj-$(CONFIG_WM8350_WATCHDOG) += wm8350_wdt.o
obj-$(CONFIG_MAX63XX_WATCHDOG) += max63xx_wdt.o
+obj-$(CONFIG_DA9052_WATCHDOG) += da9052_wdt.o
obj-$(CONFIG_SOFT_WATCHDOG) += softdog.o
diff --git a/drivers/watchdog/da9052_wdt.c b/drivers/watchdog/da9052_wdt.c
new file mode 100644
index 0000000..b08091e
--- /dev/null
+++ b/drivers/watchdog/da9052_wdt.c
@@ -0,0 +1,333 @@
+/*
+ * System monitoring driver for DA9052 PMICs.
+ *
+ * Copyright(c) 2012 Dialog Semiconductor Ltd.
+ *
+ * Author: Dajun Chen <dchen@diasemi.com>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ */
+
+#include <linux/miscdevice.h>
+#include <linux/module.h>
+#include <linux/delay.h>
+#include <linux/fs.h>
+#include <linux/uaccess.h>
+#include <linux/platform_device.h>
+#include <linux/time.h>
+#include <linux/watchdog.h>
+#include <linux/types.h>
+#include <linux/kernel.h>
+
+#include <linux/mfd/da9052/reg.h>
+#include <linux/mfd/da9052/da9052.h>
+
+static int nowayout = WATCHDOG_NOWAYOUT;
+static int wdt_state = WDIOS_DISABLECARD;
+static struct miscdevice da9052_wdt_miscdev;
+static unsigned long da9052_wdt_users;
+static int da9052_wdt_expect_close;
+struct da9052 *da9052;
+static DEFINE_MUTEX(wdt_mutex);
+
+static struct {
+ u8 reg_val;
+ int time; /* Seconds */
+} da9052_wdt_maps[] = {
+ { 1, 2 },
+ { 2, 4 },
+ { 3, 8 },
+ { 4, 16 },
+ { 5, 32 },
+ { 5, 33 }, /* Actual time 32.768s so included both 32s and 33s */
+ { 6, 65 },
+ { 6, 66 }, /* Actual time 65.536s so include both, 65s and 66s */
+ { 7, 131 },
+};
+
+static int da9052_wdt_set_timeout(struct da9052 *da9052, unsigned char timeout)
+{
+ int ret;
+
+ /* Disable the Watchdog timer for 150us before changing the
+ * time out value
+ */
+ ret = da9052_reg_update(da9052, DA9052_CONTROL_D_REG,
+ DA9052_CONTROLD_TWDSCALE, 0);
+ if (ret < 0) {
+ dev_err(da9052->dev, "Failed to disable watchdog bit, %d\n",
+ ret);
+ return ret;
+ }
+
+ mutex_lock(&wdt_mutex);
+ wdt_state = (timeout == 0) ? WDIOS_DISABLECARD : WDIOS_ENABLECARD;
+ mutex_unlock(&wdt_mutex);
+
+ if (timeout) {
+ udelay(150);
+
+ /* Set the desired timeout */
+ ret = da9052_reg_update(da9052, DA9052_CONTROL_D_REG,
+ DA9052_CONTROLD_TWDSCALE, timeout);
+ if (ret < 0) {
+ dev_err(da9052->dev,
+ "Failed to update timescale bit, %d\n", ret);
+ return ret;
+ }
+ }
+
+ return 0;
+}
+
+static int da9052_wdt_start(struct da9052 *da9052)
+{
+ int ret = 0;
+
+
+ if (wdt_state == WDIOS_DISABLECARD) {
+ /* Default 2.048s */
+ ret = da9052_wdt_set_timeout(da9052, 1);
+ if (ret <= 0)
+ goto err;
+
+ mutex_lock(&wdt_mutex);
+ wdt_state = WDIOS_ENABLECARD;
+ mutex_unlock(&wdt_mutex);
+ }
+
+err:
+ return ret;
+}
+
+static int da9052_wdt_stop(struct da9052 *da9052)
+{
+ int ret = 0;
+
+ mutex_lock(&wdt_mutex);
+
+ if (wdt_state == WDIOS_ENABLECARD) {
+ ret = da9052_reg_update(da9052, DA9052_CONTROL_D_REG,
+ DA9052_CONTROLD_TWDSCALE, 0);
+ if (ret < 0) {
+ dev_err(da9052->dev,
+ "Failed to disable watchdog bit strobe bit, %d\n",
+ ret);
+ goto err;
+ }
+
+ wdt_state = WDIOS_DISABLECARD;
+ }
+
+err:
+ mutex_unlock(&wdt_mutex);
+ return ret;
+}
+
+static void da9052_wdt_strobe(struct da9052 *da9052)
+{
+ int ret;
+
+ if (wdt_state == WDIOS_ENABLECARD) {
+ ret = da9052_reg_update(da9052, DA9052_CONTROL_D_REG,
+ DA9052_CONTROLD_WATCHDOG, 1 << 7);
+ if (ret < 0) {
+ dev_err(da9052->dev,
+ "Failed to update watchdog strobe bit, %d\n",
+ ret);
+ return;
+ }
+ }
+}
+
+static int da9052_wdt_open(struct inode *inode, struct file *file)
+{
+ int ret;
+
+ if (test_and_set_bit(0, &da9052_wdt_users))
+ return -EBUSY;
+
+ ret = da9052_wdt_start(da9052);
+ if (ret < 0)
+ return ret;
+
+ return nonseekable_open(inode, file);
+}
+
+static int da9052_wdt_release(struct inode *inode, struct file *file)
+{
+ int ret = 0;
+
+ if (da9052_wdt_expect_close == 42)
+ ret = da9052_wdt_stop(da9052);
+ else
+ da9052_wdt_strobe(da9052);
+
+ da9052_wdt_expect_close = 0;
+ clear_bit(0, &da9052_wdt_users);
+
+ return ret;
+}
+
+static struct watchdog_info da9052_wdt_info = {
+ .options = WDIOF_SETTIMEOUT | WDIOF_KEEPALIVEPING,
+ .identity = "DA9052 Watchdog",
+};
+
+static long da9052_wdt_ioctl(struct file *file, uint cmd, unsigned long arg)
+{
+ void __user *argp = (void __user *)arg;
+ int ret = 0, timeout, i, __user *p = argp;
+
+ switch (cmd) {
+ case WDIOC_GETSUPPORT:
+ ret = copy_to_user(argp, &da9052_wdt_info,
+ sizeof(da9052_wdt_info)) ? -EFAULT : 0;
+ break;
+ case WDIOC_GETSTATUS:
+ case WDIOC_GETBOOTSTATUS:
+ ret = put_user(0, p);
+ break;
+ case WDIOC_SETOPTIONS:
+ {
+ int options;
+ ret = get_user(options, p);
+ if (ret)
+ break;
+
+ if (options == WDIOS_ENABLECARD)
+ ret = da9052_wdt_start(da9052);
+
+ if (options == WDIOS_DISABLECARD)
+ ret = da9052_wdt_stop(da9052);
+
+ break;
+ }
+ case WDIOC_KEEPALIVE:
+ da9052_wdt_strobe(da9052);
+ break;
+ case WDIOC_SETTIMEOUT:
+ ret = get_user(timeout, p);
+ if (ret)
+ break;
+
+ for (i = 0; i < ARRAY_SIZE(da9052_wdt_maps); i++)
+ if (da9052_wdt_maps[i].time == timeout)
+ break;
+ if (i == ARRAY_SIZE(da9052_wdt_maps))
+ ret = -EINVAL;
+ else
+ ret = da9052_wdt_set_timeout(da9052,
+ da9052_wdt_maps[i].reg_val);
+
+ break;
+ case WDIOC_GETTIMEOUT:
+ ret = da9052_reg_read(da9052, DA9052_CONTROL_D_REG);
+ if (ret < 0)
+ break;
+
+ ret &= DA9052_CONTROLD_TWDSCALE;
+ for (i = 0; i < ARRAY_SIZE(da9052_wdt_maps); i++)
+ if (da9052_wdt_maps[i].reg_val == ret)
+ break;
+ if (i == ARRAY_SIZE(da9052_wdt_maps))
+ ret = -EINVAL;
+ else
+ ret = put_user(da9052_wdt_maps[i].time, p);
+
+ break;
+ default:
+ return -ENOTTY;
+ }
+
+ return ret;
+}
+
+static ssize_t da9052_wdt_write(struct file *file,
+ const char __user *data, size_t count,
+ loff_t *ppos)
+{
+ size_t i;
+
+ /* Check the magic character 'V' and reload the timer */
+ if (count) {
+ if (!nowayout) {
+ da9052_wdt_expect_close = 0;
+
+ /* scan for magic character */
+ for (i = 0; i != count; i++) {
+ char c;
+ if (get_user(c, data + i))
+ return -EFAULT;
+ if (c == 'V')
+ da9052_wdt_expect_close = 42;
+ }
+ /* someone wrote to us, we should reload the timer */
+ da9052_wdt_strobe(da9052);
+ }
+ }
+ return count;
+}
+
+static const struct file_operations da9052_wdt_fops = {
+ .owner = THIS_MODULE,
+ .llseek = no_llseek,
+ .unlocked_ioctl = da9052_wdt_ioctl,
+ .write = da9052_wdt_write,
+ .open = da9052_wdt_open,
+ .release = da9052_wdt_release,
+};
+
+static struct miscdevice da9052_wdt_miscdev = {
+ .minor = WATCHDOG_MINOR,
+ .name = "da9052-wdt",
+ .fops = &da9052_wdt_fops,
+};
+
+static int __devinit da9052_wdt_probe(struct platform_device *pdev)
+{
+ int ret;
+
+ da9052 = dev_get_drvdata(pdev->dev.parent);
+
+ ret = da9052_reg_update(da9052, DA9052_CONTROL_D_REG,
+ DA9052_CONTROLD_TWDSCALE, 0);
+ if (ret < 0) {
+ dev_err(&pdev->dev, "Failed to disable watchdog bits, %d\n",
+ ret);
+ return ret;
+ }
+
+ da9052_wdt_miscdev.parent = &pdev->dev;
+
+ ret = misc_register(&da9052_wdt_miscdev);
+
+ return ret;
+}
+
+static int __devexit da9052_wdt_remove(struct platform_device *dev)
+{
+ misc_deregister(&da9052_wdt_miscdev);
+
+ return 0;
+}
+
+static struct platform_driver da9052_wdt_driver = {
+ .probe = da9052_wdt_probe,
+ .remove = __devexit_p(da9052_wdt_remove),
+ .driver = {
+ .name = "da9052-watchdog",
+ .owner = THIS_MODULE,
+ },
+};
+
+module_platform_driver(da9052_wdt_driver);
+
+MODULE_AUTHOR("David Dajun Chen <dchen@diasemi.com>");
+MODULE_DESCRIPTION("DA9052 SM Device Driver");
+MODULE_LICENSE("GPL");
+MODULE_ALIAS("platform:da9052-wdt");



\
 
 \ /
  Last update: 2012-02-06 13:57    [W:0.067 / U:3.828 seconds]
©2003-2017 Jasper Spaans. hosted at Digital OceanAdvertise on this site