Subject: [linux-sunxi] [PATCH 2/4] power: add axp20x-battery driver

From: [email-masked] (Icenowy Zheng)
Date: Tue, 05 Jul 2016 16:47:38 +0800

05.07.2016, 13:26, "Michael Haas" <[email-masked]>:
> Hi,
>
> nice work! Is this in any way related to Bruno Pr?monts driver for the
> axp20x?
>
> I've got a reworked version of that lying around, but it's not quite
> ready for submission. Do you know what pieces are missing in your driver
> for axp20x support - as opposed to axp22x, which is already working?
>
> Michael
>
> On 01.07.2016 11:29, Icenowy Zheng wrote:
>> ?This driver is the battery power supply driver of axp20x PMIC. Currently
>> ?it supports only AXP22x variants.
>>
>> ?Signed-off-by: Icenowy Zheng <[email-masked]>
>> ?---
>> ???drivers/mfd/axp20x.c | 14 +++
>> ???drivers/power/Makefile | 1 +
>> ???drivers/power/axp20x_battery.c | 254 +++++++++++++++++++++++++++++++++++++++++
>> ???3 files changed, 269 insertions(+)
>> ???create mode 100644 drivers/power/axp20x_battery.c
>>
>> ?diff --git a/drivers/mfd/axp20x.c b/drivers/mfd/axp20x.c
>> ?index cee5288..064e5015 100644
>> ?--- a/drivers/mfd/axp20x.c
>> ?+++ b/drivers/mfd/axp20x.c
>> ?@@ -166,6 +166,15 @@ static struct resource axp22x_usb_power_supply_resources[] = {
>> ???????????DEFINE_RES_IRQ_NAMED(AXP22X_IRQ_VBUS_REMOVAL, "VBUS_REMOVAL"),
>> ???};
>>
>> ?+static struct resource axp22x_battery_resources[] = {
>> ?+ DEFINE_RES_IRQ_NAMED(AXP22X_IRQ_BATT_PLUGIN, "BATT_PLUGIN"),
>> ?+ DEFINE_RES_IRQ_NAMED(AXP22X_IRQ_BATT_REMOVAL, "BATT_REMOVAL"),
>> ?+ DEFINE_RES_IRQ_NAMED(AXP22X_IRQ_BATT_ENT_ACT_MODE, "BATT_ENT_ACT_MODE"),
>> ?+ DEFINE_RES_IRQ_NAMED(AXP22X_IRQ_BATT_EXIT_ACT_MODE, "BATT_EXIT_ACT_MODE"),
>> ?+ DEFINE_RES_IRQ_NAMED(AXP22X_IRQ_CHARG, "CHARG"),
>> ?+ DEFINE_RES_IRQ_NAMED(AXP22X_IRQ_CHARG_DONE, "CHARG_DONE"),
>> ?+};
>> ?+
>> ???static struct resource axp22x_pek_resources[] = {
>> ???????????{
>> ???????????????????.name = "PEK_DBR",
>> ?@@ -538,6 +547,11 @@ static struct mfd_cell axp22x_cells[] = {
>> ???????????????????.of_compatible = "x-powers,axp202-usb-power-supply",
>> ???????????????????.num_resources = ARRAY_SIZE(axp22x_usb_power_supply_resources),
>> ???????????????????.resources = axp22x_usb_power_supply_resources,
>> ?+ }, {
>> ?+ .name = "axp20x-battery",
>> ?+ .of_compatible = "x-powers,axp202-battery",
>> ?+ .num_resources = ARRAY_SIZE(axp22x_battery_resources),
>> ?+ .resources = axp22x_battery_resources,
>> ???????????},
>> ???};
>>
>> ?diff --git a/drivers/power/Makefile b/drivers/power/Makefile
>> ?index e46b75d..1452d23 100644
>> ?--- a/drivers/power/Makefile
>> ?+++ b/drivers/power/Makefile
>> ?@@ -10,6 +10,7 @@ obj-$(CONFIG_GENERIC_ADC_BATTERY) += generic-adc-battery.o
>> ???obj-$(CONFIG_PDA_POWER) += pda_power.o
>> ???obj-$(CONFIG_APM_POWER) += apm_power.o
>> ???obj-$(CONFIG_AXP20X_POWER) += axp20x_usb_power.o
>> ?+obj-$(CONFIG_AXP20X_POWER) += axp20x_battery.o
>> ???obj-$(CONFIG_MAX8925_POWER) += max8925_power.o
>> ???obj-$(CONFIG_WM831X_BACKUP) += wm831x_backup.o
>> ???obj-$(CONFIG_WM831X_POWER) += wm831x_power.o
>> ?diff --git a/drivers/power/axp20x_battery.c b/drivers/power/axp20x_battery.c
>> ?new file mode 100644
>> ?index 0000000..8fac2cd
>> ?--- /dev/null
>> ?+++ b/drivers/power/axp20x_battery.c
>> ?@@ -0,0 +1,254 @@
>> ?+/*
>> ?+ * AXP20x PMIC battery status driver
>> ?+ *
>> ?+ * Copyright (C) 2016 Icenowy Zheng <[email-masked]>
>> ?+ * Copyright (C) 2015 Hans de Goede <[email-masked]>
>> ?+ * Copyright (C) 2014 Bruno Pr?mont <[email-masked]>
>> ?+ *
>> ?+ * 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/device.h>
>> ?+#include <linux/init.h>
>> ?+#include <linux/interrupt.h>
>> ?+#include <linux/kernel.h>
>> ?+#include <linux/mfd/axp20x.h>
>> ?+#include <linux/module.h>
>> ?+#include <linux/of.h>
>> ?+#include <linux/platform_device.h>
>> ?+#include <linux/power_supply.h>
>> ?+#include <linux/regmap.h>
>> ?+#include <linux/slab.h>
>> ?+
>> ?+#define DRVNAME "axp20x-battery"
>> ?+
>> ?+#define AXP20X_PWR_STATUS_ACIN_USED BIT(6)
>> ?+#define AXP20X_PWR_STATUS_VBUS_USED BIT(4)
>> ?+#define AXP20X_PWR_STATUS_BAT_DIRECTION BIT(2)
>> ?+
>> ?+#define AXP20X_OP_MODE_CHARGING BIT(6)
>> ?+#define AXP20X_OP_MODE_BATTERY_PRESENT BIT(5)
>> ?+#define AXP20X_OP_MODE_BATTERY_ACTIVE BIT(3)
>> ?+
>> ?+#define AXP20X_CAPACITY_CORRECT BIT(7)
>> ?+
>> ?+struct axp20x_battery {
>> ?+ struct axp20x_dev *axp20x;
>> ?+ struct regmap *regmap;
>> ?+ struct power_supply *supply;
>> ?+};
>> ?+
>> ?+static irqreturn_t axp20x_battery_irq(int irq, void *devid)
>> ?+{
>> ?+ struct axp20x_battery *power = devid;
>> ?+
>> ?+ power_supply_changed(power->supply);
>> ?+
>> ?+ return IRQ_HANDLED;
>> ?+}
>> ?+
>> ?+static int axp20x_battery_get_property(struct power_supply *psy,
>> ?+ enum power_supply_property psp, union power_supply_propval *val)
>> ?+{
>> ?+ struct axp20x_battery *power = power_supply_get_drvdata(psy);
>> ?+ unsigned int input, op_mode, capacity, dh, dl;
>> ?+ int ret, ext;
>> ?+
>> ?+ /* All the properties below need the input-status reg value */
>> ?+ ret = regmap_read(power->regmap, AXP20X_PWR_INPUT_STATUS, &input);
>> ?+ if (ret)
>> ?+ return ret;
>> ?+
>> ?+ ret = regmap_read(power->regmap, AXP20X_PWR_OP_MODE, &op_mode);
>> ?+ if (ret)
>> ?+ return ret;
>> ?+
>> ?+ switch (psp) {
>> ?+ case POWER_SUPPLY_PROP_HEALTH:
>> ?+ if (!(op_mode & AXP20X_OP_MODE_BATTERY_PRESENT)) {
>> ?+ val->intval = POWER_SUPPLY_HEALTH_UNKNOWN;
>> ?+ break;
>> ?+ }
>> ?+
>> ?+ val->intval = POWER_SUPPLY_HEALTH_GOOD;
>> ?+
>> ?+ if (op_mode & AXP20X_OP_MODE_BATTERY_ACTIVE) {
>> ?+ /* AXP20X is now trying to re-activate the battery */
>> ?+ val->intval = POWER_SUPPLY_HEALTH_DEAD;
>> ?+ break;
>> ?+ }
>> ?+ break;
>> ?+ case POWER_SUPPLY_PROP_PRESENT:
>> ?+ val->intval = !!(op_mode & AXP20X_OP_MODE_BATTERY_PRESENT);
>> ?+ break;
>> ?+ case POWER_SUPPLY_PROP_CAPACITY:
>> ?+ ret = regmap_read(power->regmap, AXP20X_FG_RES, &capacity);
>> ?+ if (ret)
>> ?+ return ret;
>> ?+ if (capacity & AXP20X_CAPACITY_CORRECT)
>> ?+ val->intval = capacity & (~AXP20X_CAPACITY_CORRECT);
>> ?+ else
>> ?+ return -EIO;
>> ?+ /* from axp_capchange function of Allwinner 3.4 driver */
>> ?+ if (val->intval == 127)
>> ?+ val->intval = 100;
>> ?+ break;
>> ?+ case POWER_SUPPLY_PROP_STATUS:
>> ?+ if (!(op_mode & AXP20X_OP_MODE_BATTERY_PRESENT)) {
>> ?+ val->intval = POWER_SUPPLY_STATUS_UNKNOWN;
>> ?+ break;
>> ?+ }
>> ?+
>> ?+ ret = regmap_read(power->regmap, AXP20X_FG_RES, &capacity);
>> ?+ if (ret)
>> ?+ return ret;
>> ?+
>> ?+ ext = (input & AXP20X_PWR_STATUS_ACIN_USED) ||
>> ?+ (input & AXP20X_PWR_STATUS_VBUS_USED);
>> ?+
>> ?+ if (op_mode & AXP20X_OP_MODE_CHARGING)
>> ?+ val->intval = POWER_SUPPLY_STATUS_CHARGING;
>> ?+ else if (!(input & AXP20X_PWR_STATUS_BAT_DIRECTION) && !ext)
>> ?+ val->intval = POWER_SUPPLY_STATUS_DISCHARGING;
>> ?+ else if (capacity == (100 | AXP20X_CAPACITY_CORRECT) ||
>> ?+ capacity == (127 | AXP20X_CAPACITY_CORRECT))
>> ?+ val->intval = POWER_SUPPLY_STATUS_FULL;
>> ?+ else
>> ?+ val->intval = POWER_SUPPLY_STATUS_NOT_CHARGING;
>> ?+ break;
>> ?+ case POWER_SUPPLY_PROP_CURRENT_NOW:
>> ?+ ret = regmap_read(power->regmap, AXP20X_BATT_DISCHRG_I_H, &dh);
>> ?+ if (ret)
>> ?+ return ret;
>> ?+ ret = regmap_read(power->regmap, AXP20X_BATT_DISCHRG_I_L, &dl);
>> ?+ if (ret)
>> ?+ return ret;
>> ?+ /* it's a 12 bit integer, high 8-bit is stored in dh */
>> ?+ val->intval = dh << 4 | dl >> 4;
>> ?+ break;
>> ?+ case POWER_SUPPLY_PROP_VOLTAGE_NOW:
>> ?+ ret = regmap_read(power->regmap, AXP20X_BATT_V_H, &dh);
>> ?+ if (ret)
>> ?+ return ret;
>> ?+ ret = regmap_read(power->regmap, AXP20X_BATT_V_L, &dl);
>> ?+ if (ret)
>> ?+ return ret;
>> ?+ /* it's a 12 bit integer, high 8-bit is stored in dh */
>> ?+ val->intval = dh << 4 | dl >> 4;
>> ?+ /* The formula below is from axp22_vbat_to_mV function
>> ?+ * of Allwinner 3.4 kernel.
>> ?+ */
>> ?+ val->intval = val->intval * 1100 / 1000;
>> ?+ break;
>> ?+ default:
>> ?+ return -EINVAL;
>> ?+ }
>> ?+
>> ?+ return 0;
>> ?+}
>> ?+
>> ?+static enum power_supply_property axp22x_battery_properties[] = {
>> ?+ POWER_SUPPLY_PROP_CAPACITY,
>> ?+ POWER_SUPPLY_PROP_HEALTH,
>> ?+ POWER_SUPPLY_PROP_PRESENT,
>> ?+ POWER_SUPPLY_PROP_STATUS,
>> ?+ POWER_SUPPLY_PROP_CURRENT_NOW,
>> ?+ POWER_SUPPLY_PROP_VOLTAGE_NOW,
>> ?+};
>> ?+
>> ?+static const struct power_supply_desc axp22x_battery_desc = {
>> ?+ .name = "axp20x-battery",
>> ?+ .type = POWER_SUPPLY_TYPE_BATTERY,
>> ?+ .properties = axp22x_battery_properties,
>> ?+ .num_properties = ARRAY_SIZE(axp22x_battery_properties),
>> ?+ .get_property = axp20x_battery_get_property,
>> ?+};
>> ?+
>> ?+static int axp20x_battery_probe(struct platform_device *pdev)
>> ?+{
>> ?+ struct axp20x_dev *axp20x = dev_get_drvdata(pdev->dev.parent);
>> ?+ struct power_supply_config psy_cfg = {};
>> ?+ struct axp20x_battery *power;
>> ?+ static const char * const axp22x_irq_names[] = {
>> ?+ "BATT_PLUGIN", "BATT_REMOVAL", "BATT_ENT_ACT_MODE",
>> ?+ "BATT_EXIT_ACT_MODE", "CHARG", "CHARG_DONE", NULL };
>> ?+ static const char * const *irq_names;
>> ?+ const struct power_supply_desc *battery_desc;
>> ?+ int i, irq, ret;
>> ?+
>> ?+ if (!of_device_is_available(pdev->dev.of_node))
>> ?+ return -ENODEV;
>> ?+
>> ?+ if (!axp20x) {
>> ?+ dev_err(&pdev->dev, "Parent drvdata not set\n");
>> ?+ return -EINVAL;
>> ?+ }
>> ?+
>> ?+ power = devm_kzalloc(&pdev->dev, sizeof(*power), GFP_KERNEL);
>> ?+ if (!power)
>> ?+ return -ENOMEM;
>> ?+
>> ?+ power->axp20x = axp20x;
>> ?+ power->regmap = axp20x->regmap;
>> ?+
>> ?+ switch (power->axp20x->variant) {
>> ?+ case AXP221_ID:
>> ?+ case AXP223_ID:
>> ?+ battery_desc = &axp22x_battery_desc;
>> ?+ irq_names = axp22x_irq_names;
>> ?+ break;
>> ?+ default:
>> ?+ dev_err(&pdev->dev, "Unsupported AXP variant: %ld\n",
>> ?+ axp20x->variant);
>> ?+ return -EINVAL;
>> ?+ }
>> ?+
>> ?+ psy_cfg.of_node = pdev->dev.of_node;
>> ?+ psy_cfg.drv_data = power;
>> ?+
>> ?+ power->supply = devm_power_supply_register(&pdev->dev, battery_desc,
>> ?+ &psy_cfg);
>> ?+ if (IS_ERR(power->supply))
>> ?+ return PTR_ERR(power->supply);
>> ?+
>> ?+ /* Request irqs after registering, as irqs may trigger immediately */
>> ?+ for (i = 0; irq_names[i]; i++) {
>> ?+ irq = platform_get_irq_byname(pdev, irq_names[i]);
>> ?+ if (irq < 0) {
>> ?+ dev_warn(&pdev->dev, "No IRQ for %s: %d\n",
>> ?+ irq_names[i], irq);
>> ?+ continue;
>> ?+ }
>> ?+ irq = regmap_irq_get_virq(axp20x->regmap_irqc, irq);
>> ?+ ret = devm_request_any_context_irq(&pdev->dev, irq,
>> ?+ axp20x_battery_irq, 0, DRVNAME, power);
>> ?+ if (ret < 0)
>> ?+ dev_warn(&pdev->dev, "Error requesting %s IRQ: %d\n",
>> ?+ irq_names[i], ret);
>> ?+ }
>> ?+
>> ?+ return 0;
>> ?+}
>> ?+
>> ?+static const struct of_device_id axp20x_battery_match[] = {
>> ?+ { .compatible = "x-powers,axp202-battery" },
>> ?+ { }
>> ?+};
>> ?+MODULE_DEVICE_TABLE(of, axp20x_battery_match);
>> ?+
>> ?+static struct platform_driver axp20x_battery_driver = {
>> ?+ .probe = axp20x_battery_probe,
>> ?+ .driver = {
>> ?+ .name = DRVNAME,
>> ?+ .of_match_table = axp20x_battery_match,
>> ?+ },
>> ?+};
>> ?+
>> ?+module_platform_driver(axp20x_battery_driver);
>> ?+
>> ?+MODULE_AUTHOR("Icenowy Zheng <[email-masked]>");
>> ?+MODULE_DESCRIPTION("AXP20x PMIC battery status driver");
>> ?+MODULE_LICENSE("GPL");

I read the datasheet of axp20x, and then found that this driver does not support backup RTC battery. 
(But maybe backup battery do not need a driver -- at least on IBM PC it has no driver)

And I don't know whether the axp20x has default Li-ion/LiPo battery OCV parameter. (axp22x seems to be have a set of default OCV)

You can test this driver on AXP20x. (I think I didn't access to AXP22x-specified registers in the power supply code)