[PATCH 4/4] power: reset: as3722: add power-off driver
Laxman Dewangan
ldewangan at nvidia.com
Tue Oct 29 08:20:05 EDT 2013
ams AS3722 supports the power off functionality to turn off
system.
Add power off driver for ams AS3722.
Signed-off-by: Laxman Dewangan <ldewangan at nvidia.com>
---
drivers/power/reset/Kconfig | 6 ++
drivers/power/reset/Makefile | 1 +
drivers/power/reset/as3722-poweroff.c | 101 +++++++++++++++++++++++++++++++++
3 files changed, 108 insertions(+), 0 deletions(-)
create mode 100644 drivers/power/reset/as3722-poweroff.c
diff --git a/drivers/power/reset/Kconfig b/drivers/power/reset/Kconfig
index 9b3ea53..6d452a7 100644
--- a/drivers/power/reset/Kconfig
+++ b/drivers/power/reset/Kconfig
@@ -6,6 +6,12 @@ menuconfig POWER_RESET
Say Y here to enable board reset and power off
+config POWER_RESET_AS3722
+ bool "ams AS3722 power-off driver"
+ depends on MFD_AS3722 && POWER_RESET
+ help
+ This driver supports turning off board via a ams AS3722 power-off.
+
config POWER_RESET_GPIO
bool "GPIO power-off driver"
depends on OF_GPIO && POWER_RESET
diff --git a/drivers/power/reset/Makefile b/drivers/power/reset/Makefile
index 3e6ed88..a5b4a77 100644
--- a/drivers/power/reset/Makefile
+++ b/drivers/power/reset/Makefile
@@ -1,3 +1,4 @@
+obj-$(CONFIG_POWER_RESET_AS3722) += as3722-poweroff.o
obj-$(CONFIG_POWER_RESET_GPIO) += gpio-poweroff.o
obj-$(CONFIG_POWER_RESET_MSM) += msm-poweroff.o
obj-$(CONFIG_POWER_RESET_QNAP) += qnap-poweroff.o
diff --git a/drivers/power/reset/as3722-poweroff.c b/drivers/power/reset/as3722-poweroff.c
new file mode 100644
index 0000000..64e7c7f
--- /dev/null
+++ b/drivers/power/reset/as3722-poweroff.c
@@ -0,0 +1,101 @@
+/*
+ * Power off driver for ams AS3722 device.
+ *
+ * Copyright (c) 2013, NVIDIA Corporation.
+ *
+ * Author: Laxman Dewangan <ldewangan at nvidia.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 version 2.
+ *
+ * This program is distributed "as is" WITHOUT ANY WARRANTY of any kind,
+ * whether express or implied; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
+ * General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA
+ * 02111-1307, USA
+ */
+
+#include <linux/mfd/as3722.h>
+#include <linux/module.h>
+#include <linux/of.h>
+#include <linux/of_device.h>
+#include <linux/platform_device.h>
+#include <linux/slab.h>
+
+struct as3722_poweroff {
+ struct device *dev;
+ struct as3722 *as3722;
+};
+
+static struct as3722_poweroff *as3722_pm_poweroff;
+
+static void as3722_pm_power_off(void)
+{
+ int ret;
+
+ if (!as3722_pm_poweroff) {
+ pr_err("AS3722 poweroff is not initialised\n");
+ return;
+ }
+
+ ret = as3722_update_bits(as3722_pm_poweroff->as3722,
+ AS3722_RESET_CONTROL_REG, AS3722_POWER_OFF, AS3722_POWER_OFF);
+ if (ret < 0)
+ dev_err(as3722_pm_poweroff->dev,
+ "RESET_CONTROL_REG update failed, %d\n", ret);
+}
+
+static int as3722_poweroff_probe(struct platform_device *pdev)
+{
+ struct as3722_poweroff *as3722_poweroff;
+ struct device_node *np = pdev->dev.parent->of_node;
+
+ if (!np)
+ return -EINVAL;
+
+ if (!of_property_read_bool(np, "ams,system-power-controller"))
+ return 0;
+
+ as3722_poweroff = devm_kzalloc(&pdev->dev, sizeof(*as3722_poweroff),
+ GFP_KERNEL);
+ if (!as3722_poweroff)
+ return -ENOMEM;
+
+ as3722_poweroff->as3722 = dev_get_drvdata(pdev->dev.parent);
+ as3722_poweroff->dev = &pdev->dev;
+ as3722_pm_poweroff = as3722_poweroff;
+ if (!pm_power_off)
+ pm_power_off = as3722_pm_power_off;
+
+ return 0;
+}
+
+static int as3722_poweroff_remove(struct platform_device *pdev)
+{
+ if (pm_power_off == as3722_pm_power_off)
+ pm_power_off = NULL;
+ as3722_pm_poweroff = NULL;
+
+ return 0;
+}
+
+static struct platform_driver as3722_poweroff_driver = {
+ .driver = {
+ .name = "as3722-power-off",
+ .owner = THIS_MODULE,
+ },
+ .probe = as3722_poweroff_probe,
+ .remove = as3722_poweroff_remove,
+};
+
+module_platform_driver(as3722_poweroff_driver);
+
+MODULE_DESCRIPTION("Power off driver for ams AS3722 PMIC Device");
+MODULE_ALIAS("platform:as3722-power-off");
+MODULE_AUTHOR("Laxman Dewangan <ldewangan at nvidia.com>");
+MODULE_LICENSE("GPL v2");
--
1.7.1.1
More information about the linux-arm-kernel
mailing list