--- /dev/null
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * extcon driver for Basin Cove PMIC
+ *
+ * Copyright (c) 2019, Intel Corporation.
+ * Author: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
+ */
+
+#include <linux/extcon-provider.h>
+#include <linux/interrupt.h>
+#include <linux/mfd/intel_soc_pmic.h>
+#include <linux/mfd/intel_soc_pmic_mrfld.h>
+#include <linux/mod_devicetable.h>
+#include <linux/module.h>
+#include <linux/platform_device.h>
+#include <linux/regmap.h>
+
+#include "extcon-intel.h"
+
+#define BCOVE_USBIDCTRL 0x19
+#define BCOVE_USBIDCTRL_ID BIT(0)
+#define BCOVE_USBIDCTRL_ACA BIT(1)
+#define BCOVE_USBIDCTRL_ALL (BCOVE_USBIDCTRL_ID | BCOVE_USBIDCTRL_ACA)
+
+#define BCOVE_USBIDSTS 0x1a
+#define BCOVE_USBIDSTS_GND BIT(0)
+#define BCOVE_USBIDSTS_RARBRC_MASK GENMASK(2, 1)
+#define BCOVE_USBIDSTS_RARBRC_SHIFT 1
+#define BCOVE_USBIDSTS_NO_ACA 0
+#define BCOVE_USBIDSTS_R_ID_A 1
+#define BCOVE_USBIDSTS_R_ID_B 2
+#define BCOVE_USBIDSTS_R_ID_C 3
+#define BCOVE_USBIDSTS_FLOAT BIT(3)
+#define BCOVE_USBIDSTS_SHORT BIT(4)
+
+#define BCOVE_CHGRIRQ_ALL (BCOVE_CHGRIRQ_VBUSDET | BCOVE_CHGRIRQ_DCDET | \
+ BCOVE_CHGRIRQ_BATTDET | BCOVE_CHGRIRQ_USBIDDET)
+
+#define BCOVE_CHGRCTRL0 0x4b
+#define BCOVE_CHGRCTRL0_CHGRRESET BIT(0)
+#define BCOVE_CHGRCTRL0_EMRGCHREN BIT(1)
+#define BCOVE_CHGRCTRL0_EXTCHRDIS BIT(2)
+#define BCOVE_CHGRCTRL0_SWCONTROL BIT(3)
+#define BCOVE_CHGRCTRL0_TTLCK BIT(4)
+#define BCOVE_CHGRCTRL0_BIT_5 BIT(5)
+#define BCOVE_CHGRCTRL0_BIT_6 BIT(6)
+#define BCOVE_CHGRCTRL0_CHR_WDT_NOKICK BIT(7)
+
+struct mrfld_extcon_data {
+ struct device *dev;
+ struct regmap *regmap;
+ struct extcon_dev *edev;
+ unsigned int status;
+ unsigned int id;
+};
+
+static const unsigned int mrfld_extcon_cable[] = {
+ EXTCON_USB,
+ EXTCON_USB_HOST,
+ EXTCON_CHG_USB_SDP,
+ EXTCON_CHG_USB_CDP,
+ EXTCON_CHG_USB_DCP,
+ EXTCON_CHG_USB_ACA,
+ EXTCON_NONE,
+};
+
+static int mrfld_extcon_clear(struct mrfld_extcon_data *data, unsigned int reg,
+ unsigned int mask)
+{
+ return regmap_update_bits(data->regmap, reg, mask, 0x00);
+}
+
+static int mrfld_extcon_set(struct mrfld_extcon_data *data, unsigned int reg,
+ unsigned int mask)
+{
+ return regmap_update_bits(data->regmap, reg, mask, 0xff);
+}
+
+static int mrfld_extcon_sw_control(struct mrfld_extcon_data *data, bool enable)
+{
+ unsigned int mask = BCOVE_CHGRCTRL0_SWCONTROL;
+ struct device *dev = data->dev;
+ int ret;
+
+ if (enable)
+ ret = mrfld_extcon_set(data, BCOVE_CHGRCTRL0, mask);
+ else
+ ret = mrfld_extcon_clear(data, BCOVE_CHGRCTRL0, mask);
+ if (ret)
+ dev_err(dev, "can't set SW control: %d\n", ret);
+ return ret;
+}
+
+static int mrfld_extcon_get_id(struct mrfld_extcon_data *data)
+{
+ struct regmap *regmap = data->regmap;
+ unsigned int id;
+ bool ground;
+ int ret;
+
+ ret = regmap_read(regmap, BCOVE_USBIDSTS, &id);
+ if (ret)
+ return ret;
+
+ if (id & BCOVE_USBIDSTS_FLOAT)
+ return INTEL_USB_ID_FLOAT;
+
+ switch ((id & BCOVE_USBIDSTS_RARBRC_MASK) >> BCOVE_USBIDSTS_RARBRC_SHIFT) {
+ case BCOVE_USBIDSTS_R_ID_A:
+ return INTEL_USB_RID_A;
+ case BCOVE_USBIDSTS_R_ID_B:
+ return INTEL_USB_RID_B;
+ case BCOVE_USBIDSTS_R_ID_C:
+ return INTEL_USB_RID_C;
+ }
+
+ /*
+ * PMIC A0 reports USBIDSTS_GND = 1 for ID_GND,
+ * but PMIC B0 reports USBIDSTS_GND = 0 for ID_GND.
+ * Thus we must check this bit at last.
+ */
+ ground = id & BCOVE_USBIDSTS_GND;
+ switch ('A' + BCOVE_MAJOR(data->id)) {
+ case 'A':
+ return ground ? INTEL_USB_ID_GND : INTEL_USB_ID_FLOAT;
+ case 'B':
+ return ground ? INTEL_USB_ID_FLOAT : INTEL_USB_ID_GND;
+ }
+
+ /* Unknown or unsupported type */
+ return INTEL_USB_ID_FLOAT;
+}
+
+static int mrfld_extcon_role_detect(struct mrfld_extcon_data *data)
+{
+ unsigned int id;
+ bool usb_host;
+ int ret;
+
+ ret = mrfld_extcon_get_id(data);
+ if (ret < 0)
+ return ret;
+
+ id = ret;
+
+ usb_host = (id == INTEL_USB_ID_GND) || (id == INTEL_USB_RID_A);
+ extcon_set_state_sync(data->edev, EXTCON_USB_HOST, usb_host);
+
+ return 0;
+}
+
+static int mrfld_extcon_cable_detect(struct mrfld_extcon_data *data)
+{
+ struct regmap *regmap = data->regmap;
+ unsigned int status, change;
+ int ret;
+
+ /*
+ * It seems SCU firmware clears the content of BCOVE_CHGRIRQ1
+ * and makes it useless for OS. Instead we compare a previously
+ * stored status to the current one, provided by BCOVE_SCHGRIRQ1.
+ */
+ ret = regmap_read(regmap, BCOVE_SCHGRIRQ1, &status);
+ if (ret)
+ return ret;
+
+ change = status ^ data->status;
+ if (!change)
+ return -ENODATA;
+
+ if (change & BCOVE_CHGRIRQ_USBIDDET) {
+ ret = mrfld_extcon_role_detect(data);
+ if (ret)
+ return ret;
+ }
+
+ data->status = status;
+
+ return 0;
+}
+
+static irqreturn_t mrfld_extcon_interrupt(int irq, void *dev_id)
+{
+ struct mrfld_extcon_data *data = dev_id;
+ int ret;
+
+ ret = mrfld_extcon_cable_detect(data);
+
+ mrfld_extcon_clear(data, BCOVE_MIRQLVL1, BCOVE_LVL1_CHGR);
+
+ return ret ? IRQ_NONE: IRQ_HANDLED;
+}
+
+static int mrfld_extcon_probe(struct platform_device *pdev)
+{
+ struct device *dev = &pdev->dev;
+ struct intel_soc_pmic *pmic = dev_get_drvdata(dev->parent);
+ struct regmap *regmap = pmic->regmap;
+ struct mrfld_extcon_data *data;
+ unsigned int id;
+ int irq, ret;
+
+ irq = platform_get_irq(pdev, 0);
+ if (irq < 0)
+ return irq;
+
+ data = devm_kzalloc(dev, sizeof(*data), GFP_KERNEL);
+ if (!data)
+ return -ENOMEM;
+
+ data->dev = dev;
+ data->regmap = regmap;
+
+ data->edev = devm_extcon_dev_allocate(dev, mrfld_extcon_cable);
+ if (IS_ERR(data->edev))
+ return -ENOMEM;
+
+ ret = devm_extcon_dev_register(dev, data->edev);
+ if (ret < 0) {
+ dev_err(dev, "can't register extcon device: %d\n", ret);
+ return ret;
+ }
+
+ ret = devm_request_threaded_irq(dev, irq, NULL, mrfld_extcon_interrupt,
+ IRQF_ONESHOT | IRQF_SHARED, pdev->name,
+ data);
+ if (ret) {
+ dev_err(dev, "can't register IRQ handler: %d\n", ret);
+ return ret;
+ }
+
+ ret = regmap_read(regmap, BCOVE_ID, &id);
+ if (ret) {
+ dev_err(dev, "can't read PMIC ID: %d\n", ret);
+ return ret;
+ }
+
+ data->id = id;
+
+ ret = mrfld_extcon_sw_control(data, true);
+ if (ret)
+ return ret;
+
+ /* Get initial state */
+ mrfld_extcon_role_detect(data);
+
+ mrfld_extcon_clear(data, BCOVE_MIRQLVL1, BCOVE_LVL1_CHGR);
+ mrfld_extcon_clear(data, BCOVE_MCHGRIRQ1, BCOVE_CHGRIRQ_ALL);
+
+ mrfld_extcon_set(data, BCOVE_USBIDCTRL, BCOVE_USBIDCTRL_ALL);
+
+ platform_set_drvdata(pdev, data);
+
+ return 0;
+}
+
+static int mrfld_extcon_remove(struct platform_device *pdev)
+{
+ struct mrfld_extcon_data *data = platform_get_drvdata(pdev);
+
+ mrfld_extcon_sw_control(data, false);
+
+ return 0;
+}
+
+static const struct platform_device_id mrfld_extcon_id_table[] = {
+ { .name = "mrfld_bcove_pwrsrc" },
+ {}
+};
+MODULE_DEVICE_TABLE(platform, mrfld_extcon_id_table);
+
+static struct platform_driver mrfld_extcon_driver = {
+ .driver = {
+ .name = "mrfld_bcove_pwrsrc",
+ },
+ .probe = mrfld_extcon_probe,
+ .remove = mrfld_extcon_remove,
+ .id_table = mrfld_extcon_id_table,
+};
+module_platform_driver(mrfld_extcon_driver);
+
+MODULE_AUTHOR("Andy Shevchenko <andriy.shevchenko@linux.intel.com>");
+MODULE_DESCRIPTION("extcon driver for Intel Merrifield Basin Cove PMIC");
+MODULE_LICENSE("GPL v2");