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Diffstat (limited to 'drivers/power/supply/generic-adc-battery.c')
-rw-r--r--drivers/power/supply/generic-adc-battery.c300
1 files changed, 300 insertions, 0 deletions
diff --git a/drivers/power/supply/generic-adc-battery.c b/drivers/power/supply/generic-adc-battery.c
new file mode 100644
index 0000000000..7bdc6b2636
--- /dev/null
+++ b/drivers/power/supply/generic-adc-battery.c
@@ -0,0 +1,300 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Generic battery driver using IIO
+ * Copyright (C) 2012, Anish Kumar <anish198519851985@gmail.com>
+ * Copyright (c) 2023, Sebastian Reichel <sre@kernel.org>
+ */
+#include <linux/interrupt.h>
+#include <linux/platform_device.h>
+#include <linux/power_supply.h>
+#include <linux/gpio/consumer.h>
+#include <linux/err.h>
+#include <linux/timer.h>
+#include <linux/jiffies.h>
+#include <linux/errno.h>
+#include <linux/init.h>
+#include <linux/module.h>
+#include <linux/slab.h>
+#include <linux/iio/consumer.h>
+#include <linux/iio/types.h>
+#include <linux/of.h>
+#include <linux/devm-helpers.h>
+
+#define JITTER_DEFAULT 10 /* hope 10ms is enough */
+
+enum gab_chan_type {
+ GAB_VOLTAGE = 0,
+ GAB_CURRENT,
+ GAB_POWER,
+ GAB_TEMP,
+ GAB_MAX_CHAN_TYPE
+};
+
+/*
+ * gab_chan_name suggests the standard channel names for commonly used
+ * channel types.
+ */
+static const char *const gab_chan_name[] = {
+ [GAB_VOLTAGE] = "voltage",
+ [GAB_CURRENT] = "current",
+ [GAB_POWER] = "power",
+ [GAB_TEMP] = "temperature",
+};
+
+struct gab {
+ struct power_supply *psy;
+ struct power_supply_desc psy_desc;
+ struct iio_channel *channel[GAB_MAX_CHAN_TYPE];
+ struct delayed_work bat_work;
+ int status;
+ struct gpio_desc *charge_finished;
+};
+
+static struct gab *to_generic_bat(struct power_supply *psy)
+{
+ return power_supply_get_drvdata(psy);
+}
+
+static void gab_ext_power_changed(struct power_supply *psy)
+{
+ struct gab *adc_bat = to_generic_bat(psy);
+
+ schedule_delayed_work(&adc_bat->bat_work, msecs_to_jiffies(0));
+}
+
+static const enum power_supply_property gab_props[] = {
+ POWER_SUPPLY_PROP_STATUS,
+};
+
+/*
+ * This properties are set based on the received platform data and this
+ * should correspond one-to-one with enum chan_type.
+ */
+static const enum power_supply_property gab_dyn_props[] = {
+ POWER_SUPPLY_PROP_VOLTAGE_NOW,
+ POWER_SUPPLY_PROP_CURRENT_NOW,
+ POWER_SUPPLY_PROP_POWER_NOW,
+ POWER_SUPPLY_PROP_TEMP,
+};
+
+static bool gab_charge_finished(struct gab *adc_bat)
+{
+ if (!adc_bat->charge_finished)
+ return false;
+ return gpiod_get_value(adc_bat->charge_finished);
+}
+
+static int gab_read_channel(struct gab *adc_bat, enum gab_chan_type channel,
+ int *result)
+{
+ int ret;
+
+ ret = iio_read_channel_processed(adc_bat->channel[channel], result);
+ if (ret < 0)
+ dev_err(&adc_bat->psy->dev, "read channel error: %d\n", ret);
+ else
+ *result *= 1000;
+
+ return ret;
+}
+
+static int gab_get_property(struct power_supply *psy,
+ enum power_supply_property psp, union power_supply_propval *val)
+{
+ struct gab *adc_bat = to_generic_bat(psy);
+
+ switch (psp) {
+ case POWER_SUPPLY_PROP_STATUS:
+ val->intval = adc_bat->status;
+ return 0;
+ case POWER_SUPPLY_PROP_VOLTAGE_NOW:
+ return gab_read_channel(adc_bat, GAB_VOLTAGE, &val->intval);
+ case POWER_SUPPLY_PROP_CURRENT_NOW:
+ return gab_read_channel(adc_bat, GAB_CURRENT, &val->intval);
+ case POWER_SUPPLY_PROP_POWER_NOW:
+ return gab_read_channel(adc_bat, GAB_POWER, &val->intval);
+ case POWER_SUPPLY_PROP_TEMP:
+ return gab_read_channel(adc_bat, GAB_TEMP, &val->intval);
+ default:
+ return -EINVAL;
+ }
+}
+
+static void gab_work(struct work_struct *work)
+{
+ struct gab *adc_bat;
+ struct delayed_work *delayed_work;
+ int status;
+
+ delayed_work = to_delayed_work(work);
+ adc_bat = container_of(delayed_work, struct gab, bat_work);
+ status = adc_bat->status;
+
+ if (!power_supply_am_i_supplied(adc_bat->psy))
+ adc_bat->status = POWER_SUPPLY_STATUS_DISCHARGING;
+ else if (gab_charge_finished(adc_bat))
+ adc_bat->status = POWER_SUPPLY_STATUS_NOT_CHARGING;
+ else
+ adc_bat->status = POWER_SUPPLY_STATUS_CHARGING;
+
+ if (status != adc_bat->status)
+ power_supply_changed(adc_bat->psy);
+}
+
+static irqreturn_t gab_charged(int irq, void *dev_id)
+{
+ struct gab *adc_bat = dev_id;
+
+ schedule_delayed_work(&adc_bat->bat_work,
+ msecs_to_jiffies(JITTER_DEFAULT));
+
+ return IRQ_HANDLED;
+}
+
+static int gab_probe(struct platform_device *pdev)
+{
+ struct gab *adc_bat;
+ struct power_supply_desc *psy_desc;
+ struct power_supply_config psy_cfg = {};
+ enum power_supply_property *properties;
+ int ret = 0;
+ int chan;
+ int index = ARRAY_SIZE(gab_props);
+ bool any = false;
+
+ adc_bat = devm_kzalloc(&pdev->dev, sizeof(*adc_bat), GFP_KERNEL);
+ if (!adc_bat)
+ return -ENOMEM;
+
+ psy_cfg.of_node = pdev->dev.of_node;
+ psy_cfg.drv_data = adc_bat;
+ psy_desc = &adc_bat->psy_desc;
+ psy_desc->name = dev_name(&pdev->dev);
+
+ /* bootup default values for the battery */
+ adc_bat->status = POWER_SUPPLY_STATUS_DISCHARGING;
+ psy_desc->type = POWER_SUPPLY_TYPE_BATTERY;
+ psy_desc->get_property = gab_get_property;
+ psy_desc->external_power_changed = gab_ext_power_changed;
+
+ /*
+ * copying the static properties and allocating extra memory for holding
+ * the extra configurable properties received from platform data.
+ */
+ properties = devm_kcalloc(&pdev->dev,
+ ARRAY_SIZE(gab_props) +
+ ARRAY_SIZE(gab_chan_name),
+ sizeof(*properties),
+ GFP_KERNEL);
+ if (!properties)
+ return -ENOMEM;
+
+ memcpy(properties, gab_props, sizeof(gab_props));
+
+ /*
+ * getting channel from iio and copying the battery properties
+ * based on the channel supported by consumer device.
+ */
+ for (chan = 0; chan < ARRAY_SIZE(gab_chan_name); chan++) {
+ adc_bat->channel[chan] = devm_iio_channel_get(&pdev->dev, gab_chan_name[chan]);
+ if (IS_ERR(adc_bat->channel[chan])) {
+ ret = PTR_ERR(adc_bat->channel[chan]);
+ if (ret != -ENODEV)
+ return dev_err_probe(&pdev->dev, ret, "Failed to get ADC channel %s\n", gab_chan_name[chan]);
+ adc_bat->channel[chan] = NULL;
+ } else if (adc_bat->channel[chan]) {
+ /* copying properties for supported channels only */
+ int index2;
+
+ for (index2 = 0; index2 < index; index2++) {
+ if (properties[index2] == gab_dyn_props[chan])
+ break; /* already known */
+ }
+ if (index2 == index) /* really new */
+ properties[index++] = gab_dyn_props[chan];
+ any = true;
+ }
+ }
+
+ /* none of the channels are supported so let's bail out */
+ if (!any)
+ return dev_err_probe(&pdev->dev, -ENODEV, "Failed to get any ADC channel\n");
+
+ /*
+ * Total number of properties is equal to static properties
+ * plus the dynamic properties.Some properties may not be set
+ * as come channels may be not be supported by the device.So
+ * we need to take care of that.
+ */
+ psy_desc->properties = properties;
+ psy_desc->num_properties = index;
+
+ adc_bat->psy = devm_power_supply_register(&pdev->dev, psy_desc, &psy_cfg);
+ if (IS_ERR(adc_bat->psy))
+ return dev_err_probe(&pdev->dev, PTR_ERR(adc_bat->psy), "Failed to register power-supply device\n");
+
+ ret = devm_delayed_work_autocancel(&pdev->dev, &adc_bat->bat_work, gab_work);
+ if (ret)
+ return dev_err_probe(&pdev->dev, ret, "Failed to register delayed work\n");
+
+ adc_bat->charge_finished = devm_gpiod_get_optional(&pdev->dev, "charged", GPIOD_IN);
+ if (adc_bat->charge_finished) {
+ int irq;
+
+ irq = gpiod_to_irq(adc_bat->charge_finished);
+ ret = devm_request_any_context_irq(&pdev->dev, irq, gab_charged,
+ IRQF_TRIGGER_RISING | IRQF_TRIGGER_FALLING,
+ "battery charged", adc_bat);
+ if (ret < 0)
+ return dev_err_probe(&pdev->dev, ret, "Failed to register irq\n");
+ }
+
+ platform_set_drvdata(pdev, adc_bat);
+
+ /* Schedule timer to check current status */
+ schedule_delayed_work(&adc_bat->bat_work,
+ msecs_to_jiffies(0));
+ return 0;
+}
+
+static int __maybe_unused gab_suspend(struct device *dev)
+{
+ struct gab *adc_bat = dev_get_drvdata(dev);
+
+ cancel_delayed_work_sync(&adc_bat->bat_work);
+ adc_bat->status = POWER_SUPPLY_STATUS_UNKNOWN;
+ return 0;
+}
+
+static int __maybe_unused gab_resume(struct device *dev)
+{
+ struct gab *adc_bat = dev_get_drvdata(dev);
+
+ /* Schedule timer to check current status */
+ schedule_delayed_work(&adc_bat->bat_work,
+ msecs_to_jiffies(JITTER_DEFAULT));
+
+ return 0;
+}
+
+static SIMPLE_DEV_PM_OPS(gab_pm_ops, gab_suspend, gab_resume);
+
+static const struct of_device_id gab_match[] = {
+ { .compatible = "adc-battery" },
+ { }
+};
+MODULE_DEVICE_TABLE(of, gab_match);
+
+static struct platform_driver gab_driver = {
+ .driver = {
+ .name = "generic-adc-battery",
+ .pm = &gab_pm_ops,
+ .of_match_table = gab_match,
+ },
+ .probe = gab_probe,
+};
+module_platform_driver(gab_driver);
+
+MODULE_AUTHOR("anish kumar <anish198519851985@gmail.com>");
+MODULE_DESCRIPTION("generic battery driver using IIO");
+MODULE_LICENSE("GPL");