--- /dev/null
+/*
+ * extcon-axp288.c - X-Power AXP288 PMIC extcon cable detection driver
+ *
+ * Copyright (C) 2015 Intel Corporation
+ * Author: Ramakrishna Pallala <ramakrishna.pallala@intel.com>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ */
+
+#include <linux/module.h>
+#include <linux/kernel.h>
+#include <linux/io.h>
+#include <linux/slab.h>
+#include <linux/interrupt.h>
+#include <linux/platform_device.h>
+#include <linux/property.h>
+#include <linux/usb/phy.h>
+#include <linux/notifier.h>
+#include <linux/extcon.h>
+#include <linux/regmap.h>
+#include <linux/gpio.h>
+#include <linux/gpio/consumer.h>
+#include <linux/mfd/axp20x.h>
+
+/* Power source status register */
+#define PS_STAT_VBUS_TRIGGER BIT(0)
+#define PS_STAT_BAT_CHRG_DIR BIT(2)
+#define PS_STAT_VBUS_ABOVE_VHOLD BIT(3)
+#define PS_STAT_VBUS_VALID BIT(4)
+#define PS_STAT_VBUS_PRESENT BIT(5)
+
+/* BC module global register */
+#define BC_GLOBAL_RUN BIT(0)
+#define BC_GLOBAL_DET_STAT BIT(2)
+#define BC_GLOBAL_DBP_TOUT BIT(3)
+#define BC_GLOBAL_VLGC_COM_SEL BIT(4)
+#define BC_GLOBAL_DCD_TOUT_MASK (BIT(6)|BIT(5))
+#define BC_GLOBAL_DCD_TOUT_300MS 0
+#define BC_GLOBAL_DCD_TOUT_100MS 1
+#define BC_GLOBAL_DCD_TOUT_500MS 2
+#define BC_GLOBAL_DCD_TOUT_900MS 3
+#define BC_GLOBAL_DCD_DET_SEL BIT(7)
+
+/* BC module vbus control and status register */
+#define VBUS_CNTL_DPDM_PD_EN BIT(4)
+#define VBUS_CNTL_DPDM_FD_EN BIT(5)
+#define VBUS_CNTL_FIRST_PO_STAT BIT(6)
+
+/* BC USB status register */
+#define USB_STAT_BUS_STAT_MASK (BIT(3)|BIT(2)|BIT(1)|BIT(0))
+#define USB_STAT_BUS_STAT_SHIFT 0
+#define USB_STAT_BUS_STAT_ATHD 0
+#define USB_STAT_BUS_STAT_CONN 1
+#define USB_STAT_BUS_STAT_SUSP 2
+#define USB_STAT_BUS_STAT_CONF 3
+#define USB_STAT_USB_SS_MODE BIT(4)
+#define USB_STAT_DEAD_BAT_DET BIT(6)
+#define USB_STAT_DBP_UNCFG BIT(7)
+
+/* BC detect status register */
+#define DET_STAT_MASK (BIT(7)|BIT(6)|BIT(5))
+#define DET_STAT_SHIFT 5
+#define DET_STAT_SDP 1
+#define DET_STAT_CDP 2
+#define DET_STAT_DCP 3
+
+/* IRQ enable-1 register */
+#define PWRSRC_IRQ_CFG_MASK (BIT(4)|BIT(3)|BIT(2))
+
+/* IRQ enable-6 register */
+#define BC12_IRQ_CFG_MASK BIT(1)
+
+#define AXP288_EXTCON_SLOW_CHARGER "SLOW-CHARGER"
+#define AXP288_EXTCON_DOWNSTREAM_CHARGER "CHARGE-DOWNSTREAM"
+#define AXP288_EXTCON_FAST_CHARGER "FAST-CHARGER"
+
+enum axp288_extcon_reg {
+ AXP288_PS_STAT_REG = 0x00,
+ AXP288_PS_BOOT_REASON_REG = 0x02,
+ AXP288_BC_GLOBAL_REG = 0x2c,
+ AXP288_BC_VBUS_CNTL_REG = 0x2d,
+ AXP288_BC_USB_STAT_REG = 0x2e,
+ AXP288_BC_DET_STAT_REG = 0x2f,
+ AXP288_PWRSRC_IRQ_CFG_REG = 0x40,
+ AXP288_BC12_IRQ_CFG_REG = 0x45,
+};
+
+enum axp288_mux_select {
+ EXTCON_GPIO_MUX_SEL_PMIC = 0,
+ EXTCON_GPIO_MUX_SEL_SOC,
+};
+
+enum axp288_extcon_irq {
+ VBUS_FALLING_IRQ = 0,
+ VBUS_RISING_IRQ,
+ MV_CHNG_IRQ,
+ BC_USB_CHNG_IRQ,
+ EXTCON_IRQ_END,
+};
+
+static const char *axp288_extcon_cables[] = {
+ AXP288_EXTCON_SLOW_CHARGER,
+ AXP288_EXTCON_DOWNSTREAM_CHARGER,
+ AXP288_EXTCON_FAST_CHARGER,
+ NULL,
+};
+
+struct axp288_extcon_info {
+ struct device *dev;
+ struct regmap *regmap;
+ struct regmap_irq_chip_data *regmap_irqc;
+ struct axp288_extcon_pdata *pdata;
+ int irq[EXTCON_IRQ_END];
+ struct extcon_dev *edev;
+ struct notifier_block extcon_nb;
+ struct usb_phy *otg;
+};
+
+/* Power up/down reason string array */
+static char *axp288_pwr_up_down_info[] = {
+ "Last wake caused by user pressing the power button",
+ "Last wake caused by a charger insertion",
+ "Last wake caused by a battery insertion",
+ "Last wake caused by SOC initiated global reset",
+ "Last wake caused by cold reset",
+ "Last shutdown caused by PMIC UVLO threshold",
+ "Last shutdown caused by SOC initiated cold off",
+ "Last shutdown caused by user pressing the power button",
+ NULL,
+};
+
+/*
+ * Decode and log the given "reset source indicator" (rsi)
+ * register and then clear it.
+ */
+static void axp288_extcon_log_rsi(struct axp288_extcon_info *info)
+{
+ char **rsi;
+ unsigned int val, i, clear_mask = 0;
+ int ret;
+
+ ret = regmap_read(info->regmap, AXP288_PS_BOOT_REASON_REG, &val);
+ for (i = 0, rsi = axp288_pwr_up_down_info; *rsi; rsi++, i++) {
+ if (val & BIT(i)) {
+ dev_dbg(info->dev, "%s\n", *rsi);
+ clear_mask |= BIT(i);
+ }
+ }
+
+ /* Clear the register value for next reboot (write 1 to clear bit) */
+ regmap_write(info->regmap, AXP288_PS_BOOT_REASON_REG, clear_mask);
+}
+
+static int axp288_handle_chrg_det_event(struct axp288_extcon_info *info)
+{
+ static bool notify_otg, notify_charger;
+ static char *cable;
+ int ret, stat, cfg, pwr_stat;
+ u8 chrg_type;
+ bool vbus_attach = false;
+
+ ret = regmap_read(info->regmap, AXP288_PS_STAT_REG, &pwr_stat);
+ if (ret < 0) {
+ dev_err(info->dev, "failed to read vbus status\n");
+ return ret;
+ }
+
+ vbus_attach = (pwr_stat & PS_STAT_VBUS_PRESENT);
+ if (!vbus_attach)
+ goto notify_otg;
+
+ /* Check charger detection completion status */
+ ret = regmap_read(info->regmap, AXP288_BC_GLOBAL_REG, &cfg);
+ if (ret < 0)
+ goto dev_det_ret;
+ if (cfg & BC_GLOBAL_DET_STAT) {
+ dev_dbg(info->dev, "can't complete the charger detection\n");
+ goto dev_det_ret;
+ }
+
+ ret = regmap_read(info->regmap, AXP288_BC_DET_STAT_REG, &stat);
+ if (ret < 0)
+ goto dev_det_ret;
+
+ chrg_type = (stat & DET_STAT_MASK) >> DET_STAT_SHIFT;
+
+ switch (chrg_type) {
+ case DET_STAT_SDP:
+ dev_dbg(info->dev, "sdp cable is connecetd\n");
+ notify_otg = true;
+ notify_charger = true;
+ cable = AXP288_EXTCON_SLOW_CHARGER;
+ break;
+ case DET_STAT_CDP:
+ dev_dbg(info->dev, "cdp cable is connecetd\n");
+ notify_otg = true;
+ notify_charger = true;
+ cable = AXP288_EXTCON_DOWNSTREAM_CHARGER;
+ break;
+ case DET_STAT_DCP:
+ dev_dbg(info->dev, "dcp cable is connecetd\n");
+ notify_charger = true;
+ cable = AXP288_EXTCON_FAST_CHARGER;
+ break;
+ default:
+ dev_warn(info->dev,
+ "disconnect or unknown or ID event\n");
+ }
+
+notify_otg:
+ if (notify_otg) {
+ /*
+ * If VBUS is absent Connect D+/D- lines to PMIC for BC
+ * detection. Else connect them to SOC for USB communication.
+ */
+ if (info->pdata->gpio_mux_cntl)
+ gpiod_set_value(info->pdata->gpio_mux_cntl,
+ vbus_attach ? EXTCON_GPIO_MUX_SEL_SOC
+ : EXTCON_GPIO_MUX_SEL_PMIC);
+
+ atomic_notifier_call_chain(&info->otg->notifier,
+ vbus_attach ? USB_EVENT_VBUS : USB_EVENT_NONE, NULL);
+ }
+
+ if (notify_charger)
+ extcon_set_cable_state(info->edev, cable, vbus_attach);
+
+ /* Clear the flags on disconnect event */
+ if (!vbus_attach)
+ notify_otg = notify_charger = false;
+
+ return 0;
+
+dev_det_ret:
+ if (ret < 0)
+ dev_err(info->dev, "failed to detect BC Mod\n");
+
+ return ret;
+}
+
+static irqreturn_t axp288_extcon_isr(int irq, void *data)
+{
+ struct axp288_extcon_info *info = data;
+ int ret;
+
+ ret = axp288_handle_chrg_det_event(info);
+ if (ret < 0)
+ dev_err(info->dev, "failed to handle the interrupt\n");
+
+ return IRQ_HANDLED;
+}
+
+static void axp288_extcon_enable_irq(struct axp288_extcon_info *info)
+{
+ /* Unmask VBUS interrupt */
+ regmap_write(info->regmap, AXP288_PWRSRC_IRQ_CFG_REG,
+ PWRSRC_IRQ_CFG_MASK);
+ regmap_update_bits(info->regmap, AXP288_BC_GLOBAL_REG,
+ BC_GLOBAL_RUN, 0);
+ /* Unmask the BC1.2 complete interrupts */
+ regmap_write(info->regmap, AXP288_BC12_IRQ_CFG_REG, BC12_IRQ_CFG_MASK);
+ /* Enable the charger detection logic */
+ regmap_update_bits(info->regmap, AXP288_BC_GLOBAL_REG,
+ BC_GLOBAL_RUN, BC_GLOBAL_RUN);
+}
+
+static int axp288_extcon_probe(struct platform_device *pdev)
+{
+ struct axp288_extcon_info *info;
+ struct axp20x_dev *axp20x = dev_get_drvdata(pdev->dev.parent);
+ int ret, i, pirq, gpio;
+
+ info = devm_kzalloc(&pdev->dev, sizeof(*info), GFP_KERNEL);
+ if (!info)
+ return -ENOMEM;
+
+ info->dev = &pdev->dev;
+ info->regmap = axp20x->regmap;
+ info->regmap_irqc = axp20x->regmap_irqc;
+ info->pdata = pdev->dev.platform_data;
+
+ if (!info->pdata) {
+ /* Try ACPI provided pdata via device properties */
+ if (!device_property_present(&pdev->dev,
+ "axp288_extcon_data\n"))
+ dev_err(&pdev->dev, "failed to get platform data\n");
+ return -ENODEV;
+ }
+ platform_set_drvdata(pdev, info);
+
+ axp288_extcon_log_rsi(info);
+
+ /* Initialize extcon device */
+ info->edev = devm_extcon_dev_allocate(&pdev->dev,
+ axp288_extcon_cables);
+ if (IS_ERR(info->edev)) {
+ dev_err(&pdev->dev, "failed to allocate memory for extcon\n");
+ return PTR_ERR(info->edev);
+ }
+
+ /* Register extcon device */
+ ret = devm_extcon_dev_register(&pdev->dev, info->edev);
+ if (ret) {
+ dev_err(&pdev->dev, "failed to register extcon device\n");
+ return ret;
+ }
+
+ /* Get otg transceiver phy */
+ info->otg = usb_get_phy(USB_PHY_TYPE_USB2);
+ if (IS_ERR(info->otg)) {
+ dev_err(&pdev->dev, "failed to get otg transceiver\n");
+ return PTR_ERR(info->otg);
+ }
+
+ /* Set up gpio control for USB Mux */
+ if (info->pdata->gpio_mux_cntl) {
+ gpio = desc_to_gpio(info->pdata->gpio_mux_cntl);
+ ret = gpio_request(gpio, "USB_MUX");
+ if (ret < 0) {
+ dev_err(&pdev->dev,
+ "failed to request the gpio=%d\n", gpio);
+ goto gpio_req_failed;
+ }
+ gpiod_direction_output(info->pdata->gpio_mux_cntl,
+ EXTCON_GPIO_MUX_SEL_PMIC);
+ }
+
+ for (i = 0; i < EXTCON_IRQ_END; i++) {
+ pirq = platform_get_irq(pdev, i);
+ info->irq[i] = regmap_irq_get_virq(info->regmap_irqc, pirq);
+ if (info->irq[i] < 0) {
+ dev_err(&pdev->dev,
+ "failed to get virtual interrupt=%d\n", pirq);
+ ret = info->irq[i];
+ goto gpio_req_failed;
+ }
+
+ ret = devm_request_threaded_irq(&pdev->dev, info->irq[i],
+ NULL, axp288_extcon_isr,
+ IRQF_ONESHOT | IRQF_NO_SUSPEND,
+ pdev->name, info);
+ if (ret) {
+ dev_err(&pdev->dev, "failed to request interrupt=%d\n",
+ info->irq[i]);
+ goto gpio_req_failed;
+ }
+ }
+
+ /* Enable interrupts */
+ axp288_extcon_enable_irq(info);
+
+ return 0;
+
+gpio_req_failed:
+ usb_put_phy(info->otg);
+ return ret;
+}
+
+static int axp288_extcon_remove(struct platform_device *pdev)
+{
+ struct axp288_extcon_info *info = platform_get_drvdata(pdev);
+
+ usb_put_phy(info->otg);
+ return 0;
+}
+
+static struct platform_driver axp288_extcon_driver = {
+ .probe = axp288_extcon_probe,
+ .remove = axp288_extcon_remove,
+ .driver = {
+ .name = "axp288_extcon",
+ },
+};
+module_platform_driver(axp288_extcon_driver);
+
+MODULE_AUTHOR("Ramakrishna Pallala <ramakrishna.pallala@intel.com>");
+MODULE_DESCRIPTION("X-Powers AXP288 extcon driver");
+MODULE_LICENSE("GPL v2");