misc: qpnp-misc: Add support for TWM mode
TWM (Traditional watch mode) is a low power mode supported
on the BG platform. PMIC is configured differently
while entering into TWM mode.
Add a sysfs node to -
1. Allow the BG daemon to enable/disable TWM mode.
echo 1 > /sys/class/pmic_twm/twm_enable --> Enable TWM mode
echo 0 > /sys/class/pmic_twm/twm_enable --> Clear TWM mode
2. Allow the BG daemon to check the TWM_EXIT state.
cat /sys/class/pmic_twm/twm_exit
Value of "1" indicates exit from TWM state
Also, add a notifier to notify other modules of the TWM enable
configuration.
Change-Id: Ide2f56a80d7b21d3def6a640db71512c20d30015
Signed-off-by: Sundara Vinayagam <sundvi@codeaurora.org>
diff --git a/drivers/misc/qpnp-misc.c b/drivers/misc/qpnp-misc.c
index 690b28b..eec0875 100644
--- a/drivers/misc/qpnp-misc.c
+++ b/drivers/misc/qpnp-misc.c
@@ -1,4 +1,4 @@
-/* Copyright (c) 2013-2014,2016-2017, The Linux Foundation. All rights reserved.
+/* Copyright (c) 2013-2014,2016-2018, The Linux Foundation. All rights reserved.
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License version 2 and
@@ -17,6 +17,7 @@
#include <linux/regmap.h>
#include <linux/of.h>
#include <linux/of_device.h>
+#include <linux/notifier.h>
#include <linux/qpnp/qpnp-misc.h>
#define QPNP_MISC_DEV_NAME "qcom,qpnp-misc"
@@ -29,8 +30,20 @@
#define PWM_SEL_MAX 0x03
#define GP_DRIVER_EN_BIT BIT(0)
+enum twm {
+ TWM_MODE_1 = 1,
+ TWM_MODE_2,
+ TWM_MODE_3,
+};
+
+enum twm_attrib {
+ TWM_ENABLE,
+ TWM_EXIT,
+};
+
static DEFINE_MUTEX(qpnp_misc_dev_list_mutex);
static LIST_HEAD(qpnp_misc_dev_list);
+static RAW_NOTIFIER_HEAD(twm_notifier);
struct qpnp_misc_version {
u8 subtype;
@@ -55,10 +68,14 @@
struct device *dev;
struct regmap *regmap;
struct qpnp_misc_version version;
+ struct class twm_class;
+ u8 twm_mode;
u32 base;
u8 pwm_sel;
bool enable_gp_driver;
+ bool support_twm_config;
+ bool twm_enable;
};
static const struct of_device_id qpnp_misc_match_table[] = {
@@ -211,12 +228,100 @@
return __misc_irqs_available(mdev_found);
}
+#define MISC_SPARE_1 0x50
+#define MISC_SPARE_2 0x51
+#define ENABLE_TWM_MODE 0x80
+#define DISABLE_TWM_MODE 0x0
+#define TWM_EXIT_BIT BIT(0)
+static ssize_t twm_enable_store(struct class *c,
+ struct class_attribute *attr,
+ const char *buf, size_t count)
+{
+ struct qpnp_misc_dev *mdev = container_of(c,
+ struct qpnp_misc_dev, twm_class);
+ u8 val = 0;
+ ssize_t rc = 0;
+
+ rc = kstrtou8(buf, 10, &val);
+ if (rc < 0)
+ return rc;
+
+ mdev->twm_enable = val ? true : false;
+
+ /* Notify the TWM state */
+ raw_notifier_call_chain(&twm_notifier,
+ mdev->twm_enable ? PMIC_TWM_ENABLE : PMIC_TWM_CLEAR, NULL);
+
+ return count;
+}
+
+static ssize_t twm_enable_show(struct class *c,
+ struct class_attribute *attr, char *buf)
+{
+ struct qpnp_misc_dev *mdev = container_of(c,
+ struct qpnp_misc_dev, twm_class);
+
+ return snprintf(buf, PAGE_SIZE, "%d\n", mdev->twm_enable);
+}
+
+static ssize_t twm_exit_show(struct class *c,
+ struct class_attribute *attr, char *buf)
+{
+ struct qpnp_misc_dev *mdev = container_of(c,
+ struct qpnp_misc_dev, twm_class);
+ int rc = 0;
+ u8 val = 0;
+
+ rc = qpnp_read_byte(mdev, MISC_SPARE_1, &val);
+ if (rc < 0) {
+ pr_err("Failed to read TWM enable (misc_spare_1) rc=%d\n", rc);
+ return rc;
+ }
+
+ pr_debug("TWM_EXIT (misc_spare_1) register = 0x%02x\n", val);
+
+ return snprintf(buf, PAGE_SIZE, "%d\n", !!(val & TWM_EXIT_BIT));
+}
+
+static struct class_attribute twm_attributes[] = {
+ [TWM_ENABLE] = __ATTR(twm_enable, 0644,
+ twm_enable_show, twm_enable_store),
+ [TWM_EXIT] = __ATTR(twm_exit, 0644,
+ twm_exit_show, NULL),
+ __ATTR_NULL,
+};
+
+int qpnp_misc_twm_notifier_register(struct notifier_block *nb)
+{
+ return raw_notifier_chain_register(&twm_notifier, nb);
+}
+EXPORT_SYMBOL(qpnp_misc_twm_notifier_register);
+
+int qpnp_misc_twm_notifier_unregister(struct notifier_block *nb)
+{
+ return raw_notifier_chain_unregister(&twm_notifier, nb);
+}
+EXPORT_SYMBOL(qpnp_misc_twm_notifier_unregister);
+
static int qpnp_misc_dt_init(struct qpnp_misc_dev *mdev)
{
struct device_node *node = mdev->dev->of_node;
u32 val;
int rc;
+ if (of_property_read_bool(mdev->dev->of_node,
+ "qcom,support-twm-config")) {
+ mdev->support_twm_config = true;
+ mdev->twm_mode = TWM_MODE_3;
+ rc = of_property_read_u8(mdev->dev->of_node, "qcom,twm-mode",
+ &mdev->twm_mode);
+ if (!rc && (mdev->twm_mode < TWM_MODE_1 ||
+ mdev->twm_mode > TWM_MODE_3)) {
+ pr_err("Invalid TWM mode %d\n", mdev->twm_mode);
+ return -EINVAL;
+ }
+ }
+
rc = of_property_read_u32(node, "reg", &mdev->base);
if (rc < 0 || !mdev->base) {
dev_err(mdev->dev, "Base address not defined or invalid\n");
@@ -270,6 +375,18 @@
break;
}
+ if (mdev->support_twm_config) {
+ mdev->twm_class.name = "pmic_twm",
+ mdev->twm_class.owner = THIS_MODULE,
+ mdev->twm_class.class_attrs = twm_attributes;
+
+ rc = class_register(&mdev->twm_class);
+ if (rc < 0) {
+ pr_err("Failed to register pmic_twm class rc=%d\n", rc);
+ return rc;
+ }
+ }
+
return 0;
}
@@ -283,6 +400,7 @@
return -ENOMEM;
mdev->dev = &pdev->dev;
+ dev_set_drvdata(&pdev->dev, mdev);
mdev->regmap = dev_get_regmap(mdev->dev->parent, NULL);
if (!mdev->regmap) {
dev_err(mdev->dev, "Parent regmap is unavailable\n");
@@ -325,8 +443,33 @@
return 0;
}
+static void qpnp_misc_shutdown(struct platform_device *pdev)
+{
+ struct qpnp_misc_dev *mdev = dev_get_drvdata(&pdev->dev);
+ int rc;
+
+ if (mdev->support_twm_config) {
+ rc = qpnp_write_byte(mdev, MISC_SPARE_2,
+ mdev->twm_enable ? mdev->twm_mode : 0x0);
+ if (rc < 0)
+ pr_err("Failed to write MISC_SPARE_2 (twm_mode) val=%d rc=%d\n",
+ mdev->twm_enable ? mdev->twm_mode : 0x0, rc);
+
+ rc = qpnp_write_byte(mdev, MISC_SPARE_1,
+ mdev->twm_enable ? ENABLE_TWM_MODE : 0x0);
+ if (rc < 0)
+ pr_err("Failed to write MISC_SPARE_1 (twm_state) val=%d rc=%d\n",
+ mdev->twm_enable ? ENABLE_TWM_MODE : 0x0, rc);
+
+ pr_debug("PMIC configured for TWM-%s MODE=%d\n",
+ mdev->twm_enable ? "enabled" : "disabled",
+ mdev->twm_mode);
+ }
+}
+
static struct platform_driver qpnp_misc_driver = {
.probe = qpnp_misc_probe,
+ .shutdown = qpnp_misc_shutdown,
.driver = {
.name = QPNP_MISC_DEV_NAME,
.owner = THIS_MODULE,