[PATCH 4/8] power: Add an axp20x-usb-power driver
Hans de Goede
hdegoede at redhat.com
Tue Jun 9 14:37:57 PDT 2015
This adds a driver for the usb power_supply bits of the axp20x PMICs.
I initially started writing my own driver, before coming aware of
Bruno Prémont's excellent earlier RFC with a driver for this.
My driver was lacking CURRENT_MAX and VOLTAGE_MIN support Bruno's
drvier has, so I've copied the code for those from his driver.
Note that the AC-power-supply and battery charger bits will need separate
drivers. Each one needs its own devictree child-node so that other
devicetree nodes can reference the right power-supply, and thus each one
will get its own mfd-cell / platform_device and platform-driver.
Cc: Bruno Prémont <bonbons at linux-vserver.org>
Signed-off-by: Hans de Goede <hdegoede at redhat.com>
---
.../bindings/power_supply/axp20x_usb_power.txt | 34 +++
drivers/power/Kconfig | 7 +
drivers/power/Makefile | 1 +
drivers/power/axp20x_usb_power.c | 241 +++++++++++++++++++++
include/linux/mfd/axp20x.h | 24 ++
5 files changed, 307 insertions(+)
create mode 100644 Documentation/devicetree/bindings/power_supply/axp20x_usb_power.txt
create mode 100644 drivers/power/axp20x_usb_power.c
diff --git a/Documentation/devicetree/bindings/power_supply/axp20x_usb_power.txt b/Documentation/devicetree/bindings/power_supply/axp20x_usb_power.txt
new file mode 100644
index 0000000..a84d801
--- /dev/null
+++ b/Documentation/devicetree/bindings/power_supply/axp20x_usb_power.txt
@@ -0,0 +1,34 @@
+AXP20x USB power supply
+
+Required Properties:
+-compatible: "x-powers,axp202-usb-power-supply"
+
+This node is a subnode of the axp20x PMIC.
+
+Example:
+
+axp209: pmic at 34 {
+ compatible = "x-powers,axp209";
+ reg = <0x34>;
+ interrupt-parent = <&nmi_intc>;
+ interrupts = <0 IRQ_TYPE_LEVEL_LOW>;
+ interrupt-controller;
+ #interrupt-cells = <1>;
+
+ regulators {
+ x-powers,dcdc-freq = <1500>;
+
+ vdd_cpu: dcdc2 {
+ regulator-always-on;
+ regulator-min-microvolt = <1000000>;
+ regulator-max-microvolt = <1450000>;
+ regulator-name = "vdd-cpu";
+ };
+
+ ...
+ };
+
+ usb_power_supply: usb_power_supply {
+ compatible = "x-powers,axp202-usb-power-supply";
+ };
+};
diff --git a/drivers/power/Kconfig b/drivers/power/Kconfig
index 4091fb0..1fee60c 100644
--- a/drivers/power/Kconfig
+++ b/drivers/power/Kconfig
@@ -439,6 +439,13 @@ config BATTERY_RT5033
The fuelgauge calculates and determines the battery state of charge
according to battery open circuit voltage.
+config AXP20X_POWER
+ tristate "AXP20x power supply driver"
+ depends on MFD_AXP20X
+ help
+ This driver provides support for the power supply features of
+ AXP20x PMIC.
+
source "drivers/power/reset/Kconfig"
endif # POWER_SUPPLY
diff --git a/drivers/power/Makefile b/drivers/power/Makefile
index b7b0181..ae0f27d 100644
--- a/drivers/power/Makefile
+++ b/drivers/power/Makefile
@@ -9,6 +9,7 @@ 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-$(CONFIG_MAX8925_POWER) += max8925_power.o
obj-$(CONFIG_WM831X_BACKUP) += wm831x_backup.o
obj-$(CONFIG_WM831X_POWER) += wm831x_power.o
diff --git a/drivers/power/axp20x_usb_power.c b/drivers/power/axp20x_usb_power.c
new file mode 100644
index 0000000..4be4c8b
--- /dev/null
+++ b/drivers/power/axp20x_usb_power.c
@@ -0,0 +1,241 @@
+/*
+ * AXP20x PMIC USB power supply status driver
+ *
+ * Copyright (C) 2015 Hans de Goede <hdegoede at redhat.com>
+ * Copyright (C) 2014 Bruno Prémont <bonbons at linux-vserver.org>
+ *
+ * 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-usb-power-supply"
+
+#define AXP20X_PWR_STATUS_VBUS_PRESENT BIT(5)
+#define AXP20X_PWR_STATUS_VBUS_USED BIT(4)
+
+#define AXP20X_USB_STATUS_VBUS_VALID BIT(2)
+
+#define AXP20X_VBUS_VHOLD_uV(b) (4000000 + (((b) >> 3) & 7) * 100000)
+#define AXP20X_VBUS_CLIMIT_MASK 3
+#define AXP20X_VBUC_CLIMIT_900mA 0
+#define AXP20X_VBUC_CLIMIT_500mA 1
+#define AXP20X_VBUC_CLIMIT_100mA 2
+#define AXP20X_VBUC_CLIMIT_NONE 3
+
+#define AXP20X_ADC_EN1_VBUS_CURR BIT(2)
+#define AXP20X_ADC_EN1_VBUS_VOLT BIT(3)
+
+#define AXP20X_VBUS_MON_VBUS_VALID BIT(3)
+
+struct axp20x_usb_power {
+ struct regmap *regmap;
+ struct power_supply *supply;
+};
+
+static irqreturn_t axp20x_usb_power_irq(int irq, void *devid)
+{
+ struct axp20x_usb_power *power = devid;
+
+ power_supply_changed(power->supply);
+
+ return IRQ_HANDLED;
+}
+
+static int axp20x_usb_power_get_property(struct power_supply *psy,
+ enum power_supply_property psp, union power_supply_propval *val)
+{
+ struct axp20x_usb_power *power = power_supply_get_drvdata(psy);
+ unsigned int input, v;
+ int r;
+
+ switch (psp) {
+ case POWER_SUPPLY_PROP_VOLTAGE_MIN:
+ r = regmap_read(power->regmap, AXP20X_VBUS_IPSOUT_MGMT, &v);
+ if (r)
+ return r;
+
+ val->intval = AXP20X_VBUS_VHOLD_uV(v);
+ return 0;
+ case POWER_SUPPLY_PROP_VOLTAGE_NOW:
+ r = axp20x_read_16bit(power->regmap, AXP20X_VBUS_V_ADC_H, 12);
+ if (r < 0)
+ return r;
+
+ val->intval = r * 1700; /* 1 step = 1.7 mV */
+ return 0;
+ case POWER_SUPPLY_PROP_CURRENT_MAX:
+ r = regmap_read(power->regmap, AXP20X_VBUS_IPSOUT_MGMT, &v);
+ if (r)
+ return r;
+
+ switch (v & AXP20X_VBUS_CLIMIT_MASK) {
+ case AXP20X_VBUC_CLIMIT_100mA:
+ val->intval = 100000;
+ break;
+ case AXP20X_VBUC_CLIMIT_500mA:
+ val->intval = 500000;
+ break;
+ case AXP20X_VBUC_CLIMIT_900mA:
+ val->intval = 900000;
+ break;
+ case AXP20X_VBUC_CLIMIT_NONE:
+ val->intval = -1;
+ break;
+ }
+ return 0;
+ case POWER_SUPPLY_PROP_CURRENT_NOW:
+ r = axp20x_read_16bit(power->regmap, AXP20X_VBUS_I_ADC_H, 12);
+ if (r < 0)
+ return r;
+
+ val->intval = r * 375; /* 1 step = 0.375 mA */
+ return 0;
+ default:
+ break;
+ }
+
+ /* All the properties below need the input-status reg value */
+ r = regmap_read(power->regmap, AXP20X_PWR_INPUT_STATUS, &input);
+ if (r)
+ return r;
+
+ switch (psp) {
+ case POWER_SUPPLY_PROP_HEALTH:
+ if (!(input & AXP20X_PWR_STATUS_VBUS_PRESENT)) {
+ val->intval = POWER_SUPPLY_HEALTH_UNKNOWN;
+ break;
+ }
+
+ r = regmap_read(power->regmap, AXP20X_USB_OTG_STATUS, &v);
+ if (r)
+ return r;
+
+ if (!(v & AXP20X_USB_STATUS_VBUS_VALID)) {
+ val->intval = POWER_SUPPLY_HEALTH_UNSPEC_FAILURE;
+ break;
+ }
+
+ val->intval = POWER_SUPPLY_HEALTH_GOOD;
+ break;
+ case POWER_SUPPLY_PROP_PRESENT:
+ val->intval = !!(input & AXP20X_PWR_STATUS_VBUS_PRESENT);
+ break;
+ case POWER_SUPPLY_PROP_ONLINE:
+ val->intval = !!(input & AXP20X_PWR_STATUS_VBUS_USED);
+ break;
+ default:
+ return -EINVAL;
+ }
+
+ return 0;
+}
+
+static enum power_supply_property axp20x_usb_power_properties[] = {
+ POWER_SUPPLY_PROP_HEALTH,
+ POWER_SUPPLY_PROP_PRESENT,
+ POWER_SUPPLY_PROP_ONLINE,
+ POWER_SUPPLY_PROP_VOLTAGE_MIN,
+ POWER_SUPPLY_PROP_VOLTAGE_NOW,
+ POWER_SUPPLY_PROP_CURRENT_MAX,
+ POWER_SUPPLY_PROP_CURRENT_NOW,
+};
+
+static const struct power_supply_desc axp20x_usb_power_desc = {
+ .name = "axp20x-usb",
+ .type = POWER_SUPPLY_TYPE_USB,
+ .properties = axp20x_usb_power_properties,
+ .num_properties = ARRAY_SIZE(axp20x_usb_power_properties),
+ .get_property = axp20x_usb_power_get_property,
+};
+
+static int axp20x_usb_power_probe(struct platform_device *pdev)
+{
+ struct axp20x_dev *axp20x = dev_get_drvdata(pdev->dev.parent);
+ struct power_supply_config psy_cfg = {};
+ struct axp20x_usb_power *power;
+ const char *irq_names[] = { "VBUS_PLUGIN", "VBUS_REMOVAL",
+ "VBUS_VALID", "VBUS_NOT_VALID" };
+ int i, irq, r;
+
+ if (!of_device_is_available(pdev->dev.of_node))
+ return -ENODEV;
+
+ power = devm_kzalloc(&pdev->dev, sizeof(*power), GFP_KERNEL);
+ if (!power)
+ return -ENOMEM;
+
+ power->regmap = axp20x->regmap;
+
+ /* Enable vbus valid checking */
+ r = regmap_update_bits(power->regmap, AXP20X_VBUS_MON,
+ AXP20X_VBUS_MON_VBUS_VALID, AXP20X_VBUS_MON_VBUS_VALID);
+ if (r)
+ return r;
+
+ /* Enable vbus voltage and current measurement */
+ r = regmap_update_bits(power->regmap, AXP20X_ADC_EN1,
+ AXP20X_ADC_EN1_VBUS_CURR | AXP20X_ADC_EN1_VBUS_VOLT,
+ AXP20X_ADC_EN1_VBUS_CURR | AXP20X_ADC_EN1_VBUS_VOLT);
+ if (r)
+ return r;
+
+ psy_cfg.of_node = pdev->dev.of_node;
+ psy_cfg.drv_data = power;
+
+ power->supply = devm_power_supply_register(&pdev->dev,
+ &axp20x_usb_power_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; i < ARRAY_SIZE(irq_names); 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);
+ r = devm_request_any_context_irq(&pdev->dev, irq,
+ axp20x_usb_power_irq, 0, DRVNAME, power);
+ if (r < 0)
+ dev_warn(&pdev->dev, "Error requesting %s IRQ: %d\n",
+ irq_names[i], r);
+ }
+
+ return 0;
+}
+
+static const struct of_device_id axp20x_usb_power_match[] = {
+ { .compatible = "x-powers,axp202-usb-power-supply" },
+ { }
+};
+MODULE_DEVICE_TABLE(of, axp20x_usb_power_match);
+
+static struct platform_driver axp20x_usb_power_driver = {
+ .probe = axp20x_usb_power_probe,
+ .driver = {
+ .name = DRVNAME,
+ .of_match_table = axp20x_usb_power_match,
+ },
+};
+
+module_platform_driver(axp20x_usb_power_driver);
+
+MODULE_AUTHOR("Hans de Goede <hdegoede at redhat.com>");
+MODULE_DESCRIPTION("AXP20x PMIC USB power supply status driver");
+MODULE_LICENSE("GPL");
diff --git a/include/linux/mfd/axp20x.h b/include/linux/mfd/axp20x.h
index f4290ae..d7adb2e 100644
--- a/include/linux/mfd/axp20x.h
+++ b/include/linux/mfd/axp20x.h
@@ -11,6 +11,8 @@
#ifndef __LINUX_MFD_AXP20X_H
#define __LINUX_MFD_AXP20X_H
+#include <linux/regmap.h>
+
enum {
AXP202_ID = 0,
AXP209_ID,
@@ -366,4 +368,26 @@ struct axp20x_fg_pdata {
int thermistor_curve[MAX_THERM_CURVE_SIZE][2];
};
+/* generic helper function for reading 9-16 bit wide regs */
+static inline int axp20x_read_16bit(struct regmap *regmap,
+ unsigned int reg, unsigned int width)
+{
+ unsigned int v, raw;
+ int r;
+
+ r = regmap_read(regmap, reg, &v);
+ if (r)
+ return r;
+
+ raw = v << (width - 8);
+
+ r = regmap_read(regmap, reg + 1, &v);
+ if (r)
+ return r;
+
+ raw |= v;
+
+ return raw;
+}
+
#endif /* __LINUX_MFD_AXP20X_H */
--
2.3.6
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