[PATCH v3] watchdog: Add DA906x PMIC watchdog driver.
Markus Pargmann
mpa at pengutronix.de
Thu Aug 14 02:57:34 PDT 2014
On Wed, Aug 13, 2014 at 10:26:22PM -0700, Guenter Roeck wrote:
> On 08/13/2014 03:46 AM, Markus Pargmann wrote:
> >From: Krystian Garbaciak <krystian.garbaciak at diasemi.com>
> >
> >This driver supports the watchdog device inside the DA906x PMIC.
> >
> >Signed-off-by: Krystian Garbaciak <krystian.garbaciak at diasemi.com>
> >Signed-off-by: Philipp Zabel <p.zabel at pengutronix.de>
> >Signed-off-by: Markus Pargmann <mpa at pengutronix.de>
>
> Couple of additional comments.
>
> Guenter
>
> >---
> > drivers/watchdog/Kconfig | 7 ++
> > drivers/watchdog/Makefile | 1 +
> > drivers/watchdog/da9063_wdt.c | 228 ++++++++++++++++++++++++++++++++++++++++++
> > 3 files changed, 236 insertions(+)
> > create mode 100644 drivers/watchdog/da9063_wdt.c
> >
> >diff --git a/drivers/watchdog/Kconfig b/drivers/watchdog/Kconfig
> >index c845527b503a..8d5c9b33552a 100644
> >--- a/drivers/watchdog/Kconfig
> >+++ b/drivers/watchdog/Kconfig
> >@@ -87,6 +87,13 @@ config DA9055_WATCHDOG
> > This driver can also be built as a module. If so, the module
> > will be called da9055_wdt.
> >
> >+config DA9063_WATCHDOG
> >+ tristate "Dialog DA9063 Watchdog"
> >+ depends on MFD_DA9063
> >+ select WATCHDOG_CORE
> >+ help
> >+ Support for the watchdog in the DA9063 PMIC.
> >+
> > config GPIO_WATCHDOG
> > tristate "Watchdog device controlled through GPIO-line"
> > depends on OF_GPIO
> >diff --git a/drivers/watchdog/Makefile b/drivers/watchdog/Makefile
> >index 7b8a91ed20e7..ce4a7632d863 100644
> >--- a/drivers/watchdog/Makefile
> >+++ b/drivers/watchdog/Makefile
> >@@ -172,6 +172,7 @@ obj-$(CONFIG_XEN_WDT) += xen_wdt.o
> > # Architecture Independent
> > obj-$(CONFIG_DA9052_WATCHDOG) += da9052_wdt.o
> > obj-$(CONFIG_DA9055_WATCHDOG) += da9055_wdt.o
> >+obj-$(CONFIG_DA9063_WATCHDOG) += da9063_wdt.o
> > obj-$(CONFIG_GPIO_WATCHDOG) += gpio_wdt.o
> > obj-$(CONFIG_WM831X_WATCHDOG) += wm831x_wdt.o
> > obj-$(CONFIG_WM8350_WATCHDOG) += wm8350_wdt.o
> >diff --git a/drivers/watchdog/da9063_wdt.c b/drivers/watchdog/da9063_wdt.c
> >new file mode 100644
> >index 000000000000..2b5ce564c4c1
> >--- /dev/null
> >+++ b/drivers/watchdog/da9063_wdt.c
> >@@ -0,0 +1,228 @@
> >+/*
> >+ * Watchdog driver for DA9063 PMICs.
> >+ *
> >+ * Copyright(c) 2012 Dialog Semiconductor Ltd.
> >+ *
> >+ * Author: Mariusz Wojtasik <mariusz.wojtasik at 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/kernel.h>
> >+#include <linux/module.h>
> >+#include <linux/watchdog.h>
> >+#include <linux/platform_device.h>
> >+#include <linux/uaccess.h>
> >+#include <linux/slab.h>
> >+#include <linux/delay.h>
> >+#include <linux/mfd/da9063/registers.h>
> >+#include <linux/mfd/da9063/core.h>
> >+#include <linux/regmap.h>
> >+
> >+/*
> >+ * Watchdog selector to timeout in seconds.
> >+ * 0: WDT disabled;
> >+ * others: timeout = 2048 ms * 2^(TWDSCALE-1).
> >+ */
> >+static const int wdt_timeout[] = { 0, 2, 4, 8, 16, 32, 65, 131 };
> >+#define DA9063_TWDSCALE_DISABLE 0
> >+#define DA9063_TWDSCALE_MIN 1
> >+#define DA9063_TWDSCALE_MAX (ARRAY_SIZE(wdt_timeout) - 1)
> >+#define DA9063_WDT_MIN_TIMEOUT wdt_timeout[DA9063_TWDSCALE_MIN]
> >+#define DA9063_WDT_MAX_TIMEOUT wdt_timeout[DA9063_TWDSCALE_MAX]
> >+#define DA9063_WDG_TIMEOUT wdt_timeout[3]
> >+
> >+struct da9063_watchdog {
> >+ struct da9063 *da9063;
> >+ struct watchdog_device wdtdev;
> >+ struct mutex lock;
> >+};
> >+
> >+static int da9063_wdt_timeout_to_sel(int secs)
> >+{
> >+ int i;
> >+
> >+ for (i = DA9063_TWDSCALE_MIN; i <= DA9063_TWDSCALE_MAX; i++) {
> >+ if (wdt_timeout[i] >= secs)
> >+ return i;
> >+ }
> >+
> >+ return -EINVAL;
> >+}
> >+
> >+static int da9063_wdt_disable(struct da9063 *da9063)
> >+{
> >+ return regmap_update_bits(da9063->regmap, DA9063_REG_CONTROL_D,
> >+ DA9063_TWDSCALE_MASK,
> >+ DA9063_TWDSCALE_DISABLE);
> >+}
> >+
> >+static int _da9063_wdt_set_timeout(struct da9063 *da9063, unsigned int regval)
> >+{
> >+ return regmap_update_bits(da9063->regmap, DA9063_REG_CONTROL_D,
> >+ DA9063_TWDSCALE_MASK, regval);
> >+}
> >+
> >+static int _da9063_wdt_kick(struct da9063 *da9063)
> >+{
> >+ return regmap_write(da9063->regmap, DA9063_REG_CONTROL_F,
> >+ DA9063_WATCHDOG);
> >+}
> >+
> >+static int da9063_wdt_start(struct watchdog_device *wdd)
> >+{
> >+ struct da9063_watchdog *wdt = watchdog_get_drvdata(wdd);
> >+ unsigned int selector;
> >+ int ret = 0;
>
> Unnecessary initialization.
Thanks, I fixed all these initializations.
>
> >+
> >+ mutex_lock(&wdt->lock);
> >+ selector = da9063_wdt_timeout_to_sel(wdt->wdtdev.timeout);
> >+ if (selector < 0) {
> >+ dev_err(wdt->da9063->dev, "Timeout out of range (timeout=%d)\n",
> >+ wdt->wdtdev.timeout);
> >+ return selector;
>
> That only works if you move the lock further down, which should be ok.
> Otherwise you'll need to assign the return code to ret and jump to
> the unlock below.
Yes, moved.
>
> >+ }
> >+
> >+ ret = _da9063_wdt_set_timeout(wdt->da9063, selector);
> >+ if (ret) {
> >+ dev_err(wdt->da9063->dev, "Watchdog failed to start (err = %d)\n",
> >+ ret);
> >+ }
> >+ mutex_unlock(&wdt->lock);
> >+
> >+ return ret;
> >+}
> >+
> >+static int da9063_wdt_stop(struct watchdog_device *wdd)
> >+{
> >+ struct da9063_watchdog *wdt = watchdog_get_drvdata(wdd);
> >+ int ret = 0;
>
> Unnecessary initialization.
>
> >+
> >+ mutex_lock(&wdt->lock);
> >+ ret = da9063_wdt_disable(wdt->da9063);
> >+ if (ret)
> >+ dev_alert(wdt->da9063->dev,
> >+ "Watchdog failed to stop (err = %d)\n", ret);
> >+ mutex_unlock(&wdt->lock);
> >+
> >+ return ret;
> >+}
> >+
> >+static int da9063_wdt_ping(struct watchdog_device *wdd)
> >+{
> >+ struct da9063_watchdog *wdt = watchdog_get_drvdata(wdd);
> >+ int ret = 0;
> >+
> Unnecessary initialization.
>
> >+ mutex_lock(&wdt->lock);
> >+ ret = _da9063_wdt_kick(wdt->da9063);
> >+ if (ret)
> >+ dev_alert(wdt->da9063->dev, "Failed to ping the watchdog (err = %d)\n",
> >+ ret);
> >+ mutex_unlock(&wdt->lock);
> >+
> >+ return ret;
> >+}
> >+
> >+static int da9063_wdt_set_timeout(struct watchdog_device *wdd,
> >+ unsigned int timeout)
>
> Sometimes it seems to me people go through great pains not to follow Linux
> indentation rules, and use the "as many different indentations as possible"
> rule instead ;-). No, I am not enforcing it; that would be up to Wim if he cares.
I fixed this indentation to the same style as the rest of the driver.
>
> >+{
> >+ struct da9063_watchdog *wdt = watchdog_get_drvdata(wdd);
> >+ unsigned int selector;
> >+ int ret;
> >+
> >+ selector = da9063_wdt_timeout_to_sel(timeout);
> >+ if (selector < 0) {
> >+ dev_err(wdt->da9063->dev, "Unsupported watchdog timeout, should be between 2 and 131\n");
> >+ return -EINVAL;
> >+ }
> >+
> >+ mutex_lock(&wdt->lock);
> >+
> >+ ret = _da9063_wdt_set_timeout(wdt->da9063, selector);
> >+ if (ret)
> >+ dev_err(wdt->da9063->dev, "Failed to set watchdog timeout (err = %d)\n",
> >+ ret);
> >+ else
> >+ wdd->timeout = wdt_timeout[selector];
> >+
> >+ mutex_unlock(&wdt->lock);
> >+
> >+ return ret;
> >+}
> >+
> >+static const struct watchdog_info da9063_watchdog_info = {
> >+ .options = WDIOF_SETTIMEOUT | WDIOF_KEEPALIVEPING,
> >+ .identity = "DA9063 Watchdog",
> >+};
> >+
> >+static const struct watchdog_ops da9063_watchdog_ops = {
> >+ .owner = THIS_MODULE,
> >+ .start = da9063_wdt_start,
> >+ .stop = da9063_wdt_stop,
> >+ .ping = da9063_wdt_ping,
> >+ .set_timeout = da9063_wdt_set_timeout,
> >+};
> >+
> >+static int da9063_wdt_probe(struct platform_device *pdev)
> >+{
> >+ int ret;
> >+ struct da9063 *da9063 = dev_get_drvdata(pdev->dev.parent);
> >+ struct da9063_watchdog *wdt;
> >+
> >+ if (!da9063)
> >+ return -EPROBE_DEFER;
>
> Can this ever happen ? Isn't this driver instantiated from its parent,
> which would ensure that the parent's driver data is set ?
No this can't happen. I replaced it with BUG_ON and also introduced a
BUG_ON check for dev.parent.
>
> >+
> >+ wdt = devm_kzalloc(&pdev->dev, sizeof(*wdt), GFP_KERNEL);
> >+ if (!wdt)
> >+ return -ENOMEM;
> >+
> >+ wdt->da9063 = da9063;
> >+ mutex_init(&wdt->lock);
> >+
> >+ wdt->wdtdev.info = &da9063_watchdog_info;
> >+ wdt->wdtdev.ops = &da9063_watchdog_ops;
> >+ wdt->wdtdev.min_timeout = DA9063_WDT_MIN_TIMEOUT;
> >+ wdt->wdtdev.max_timeout = DA9063_WDT_MAX_TIMEOUT;
> >+ wdt->wdtdev.timeout = DA9063_WDG_TIMEOUT;
> >+
> >+ if (IS_ENABLED(CONFIG_WATCHDOG_NOWAYOUT))
> >+ wdt->wdtdev.status = WATCHDOG_NOWAYOUT_INIT_STATUS;
>
> You don't need the if() here. That is embedded in WATCHDOG_NOWAYOUT_INIT_STATUS.
Removed.
Thanks,
Markus
--
Pengutronix e.K. | |
Industrial Linux Solutions | http://www.pengutronix.de/ |
Peiner Str. 6-8, 31137 Hildesheim, Germany | Phone: +49-5121-206917-0 |
Amtsgericht Hildesheim, HRA 2686 | Fax: +49-5121-206917-5555 |
-------------- next part --------------
A non-text attachment was scrubbed...
Name: signature.asc
Type: application/pgp-signature
Size: 836 bytes
Desc: Digital signature
URL: <http://lists.infradead.org/pipermail/linux-arm-kernel/attachments/20140814/0c823e14/attachment-0001.sig>
More information about the linux-arm-kernel
mailing list