Add support for control peripheral of EUD (Embedded USB Debugger) to listen to events such as USB attach/detach, charger enable/disable, pet EUD to indicate software is functional. Reusing the platform device kobj, sysfs entry 'enable' is created to enable or disable EUD.
Signed-off-by: Satya Durga Srinivasu Prabhala <[email protected]> Signed-off-by: Prakruthi Deepak Heragu <[email protected]> --- drivers/soc/qcom/Kconfig | 12 ++ drivers/soc/qcom/Makefile | 1 + drivers/soc/qcom/eud.c | 344 ++++++++++++++++++++++++++++++++++++++++++++++ 3 files changed, 357 insertions(+) create mode 100644 drivers/soc/qcom/eud.c diff --git a/drivers/soc/qcom/Kconfig b/drivers/soc/qcom/Kconfig index 5856e79..12669ec 100644 --- a/drivers/soc/qcom/Kconfig +++ b/drivers/soc/qcom/Kconfig @@ -136,4 +136,16 @@ config QCOM_APR application processor and QDSP6. APR is used by audio driver to configure QDSP6 ASM, ADM and AFE modules. + +config QCOM_EUD + tristate "QTI Embedded USB Debugger (EUD)" + depends on ARCH_QCOM + help + The Embedded USB Debugger (EUD) driver is a driver for the + control peripheral which waits on events like USB attach/detach + and charger enable/disable. The control peripheral further helps + support the USB-based debug and trace capabilities. + This module enables support for Qualcomm Technologies, Inc. + Embedded USB Debugger (EUD). + If unsure, say N. endmenu diff --git a/drivers/soc/qcom/Makefile b/drivers/soc/qcom/Makefile index 19dcf95..dd4701b 100644 --- a/drivers/soc/qcom/Makefile +++ b/drivers/soc/qcom/Makefile @@ -15,3 +15,4 @@ obj-$(CONFIG_QCOM_SMP2P) += smp2p.o obj-$(CONFIG_QCOM_SMSM) += smsm.o obj-$(CONFIG_QCOM_WCNSS_CTRL) += wcnss_ctrl.o obj-$(CONFIG_QCOM_APR) += apr.o +obj-$(CONFIG_QCOM_EUD) += eud.o diff --git a/drivers/soc/qcom/eud.c b/drivers/soc/qcom/eud.c new file mode 100644 index 0000000..bd885d6 --- /dev/null +++ b/drivers/soc/qcom/eud.c @@ -0,0 +1,344 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * Copyright (c) 2016-2018, The Linux Foundation. All rights reserved. + */ + +#include <linux/kernel.h> +#include <linux/device.h> +#include <linux/module.h> +#include <linux/slab.h> +#include <linux/interrupt.h> +#include <linux/err.h> +#include <linux/platform_device.h> +#include <linux/extcon.h> +#include <linux/delay.h> +#include <linux/sysfs.h> +#include <linux/io.h> +#include <linux/bitops.h> +#include <linux/workqueue.h> +#include <linux/power_supply.h> + +#define EUD_ENABLE_CMD 1 +#define EUD_DISABLE_CMD 0 + +#define EUD_REG_INT1_EN_MASK 0x0024 +#define EUD_REG_INT_STATUS_1 0x0044 +#define EUD_REG_CTL_OUT_1 0x0074 +#define EUD_REG_VBUS_INT_CLR 0x0080 +#define EUD_REG_CHGR_INT_CLR 0x0084 +#define EUD_REG_CSR_EUD_EN 0x1014 +#define EUD_REG_SW_ATTACH_DET 0x1018 + +#define EUD_INT_VBUS BIT(2) +#define EUD_INT_CHGR BIT(3) +#define EUD_INT_SAFE_MODE BIT(4) +#define EUD_INT_ALL (EUD_INT_VBUS|EUD_INT_CHGR|\ + EUD_INT_SAFE_MODE) + +struct eud_chip { + struct device *dev; + int eud_irq; + unsigned int extcon_id; + unsigned int int_status; + bool usb_attach; + bool chgr_enable; + void __iomem *eud_reg_base; + struct extcon_dev *extcon; + int enable; + struct work_struct eud_work; +}; + +static const unsigned int eud_extcon_cable[] = { + EXTCON_USB, + EXTCON_CHG_USB_SDP, + EXTCON_NONE, +}; + +static int enable_eud(struct eud_chip *priv) +{ + struct power_supply *usb_psy = NULL; + union power_supply_propval pval = {0}; + union power_supply_propval tval = {0}; + int ret; + + usb_psy = power_supply_get_by_name("usb"); + if (!usb_psy) + return -1; + + ret = power_supply_get_property(usb_psy, + POWER_SUPPLY_PROP_PRESENT, &pval); + if (ret) + return ret; + + ret = power_supply_get_property(usb_psy, + POWER_SUPPLY_PROP_REAL_TYPE, &tval); + if (ret) + return ret; + + if (!pval.intval || (tval.intval != POWER_SUPPLY_TYPE_USB && + tval.intval != POWER_SUPPLY_TYPE_USB_CDP)) + return -1; + + /* write into CSR to enable EUD */ + writel_relaxed(BIT(0), priv->eud_reg_base + EUD_REG_CSR_EUD_EN); + /* Enable vbus, chgr & safe mode warning interrupts */ + writel_relaxed(EUD_INT_VBUS | EUD_INT_CHGR | EUD_INT_SAFE_MODE, + priv->eud_reg_base + EUD_REG_INT1_EN_MASK); + + /* Ensure Register Writes Complete */ + wmb(); + + /* + * Set the default cable state to usb connect and charger + * enable + */ + ret = extcon_set_state_sync(priv->extcon, EXTCON_USB, true); + if (ret) + return ret; + ret = extcon_set_state_sync(priv->extcon, + EXTCON_CHG_USB_SDP, true); + if (ret) + return ret; + + return 0; +} + +static void disable_eud(struct eud_chip *priv) +{ + /* write into CSR to disable EUD */ + writel_relaxed(0, priv->eud_reg_base + EUD_REG_CSR_EUD_EN); +} + +static ssize_t eud_enable_show(struct device *dev, + struct device_attribute *attr, char *buf) +{ + struct eud_chip *chip = dev_get_drvdata(dev); + + return snprintf(buf, sizeof(int), "%d", chip->enable); +} + +static ssize_t eud_enable_store(struct device *dev, + struct device_attribute *attr, + const char *buf, size_t count) +{ + struct eud_chip *chip = dev_get_drvdata(dev); + int enable = 0; + int ret = 0; + + if (sscanf(buf, "%du", &enable) != 1) + return -EINVAL; + + if (enable == EUD_ENABLE_CMD) + ret = enable_eud(chip); + else if (enable == EUD_DISABLE_CMD) + disable_eud(chip); + if (!ret) + chip->enable = enable; + return count; +} + +struct device_attribute eud_attribute = { + .attr.name = "enable", + .attr.mode = 0644, + .show = eud_enable_show, + .store = eud_enable_store, +}; + +static void eud_event_notifier(struct work_struct *eud_work) +{ + struct eud_chip *chip = container_of(eud_work, struct eud_chip, + eud_work); + int ret; + + if (chip->int_status == EUD_INT_VBUS) { + ret = extcon_set_state_sync(chip->extcon, chip->extcon_id, + chip->usb_attach); + if (ret) + return; + } else if (chip->int_status == EUD_INT_CHGR) { + ret = extcon_set_state_sync(chip->extcon, chip->extcon_id, + chip->chgr_enable); + if (ret) + return; + } +} + +static void usb_attach_detach(struct eud_chip *chip) +{ + u32 reg; + + chip->extcon_id = EXTCON_USB; + /* read ctl_out_1[4] to find USB attach or detach event */ + reg = readl_relaxed(chip->eud_reg_base + EUD_REG_CTL_OUT_1); + if (reg & BIT(4)) + chip->usb_attach = true; + else + chip->usb_attach = false; + + schedule_work(&chip->eud_work); + + /* set and clear vbus_int_clr[0] to clear interrupt */ + writel_relaxed(BIT(0), chip->eud_reg_base + EUD_REG_VBUS_INT_CLR); + /* Ensure Register Writes Complete */ + wmb(); + writel_relaxed(0, chip->eud_reg_base + EUD_REG_VBUS_INT_CLR); +} + +static void chgr_enable_disable(struct eud_chip *chip) +{ + u32 reg; + + chip->extcon_id = EXTCON_CHG_USB_SDP; + /* read ctl_out_1[6] to find charger enable or disable event */ + reg = readl_relaxed(chip->eud_reg_base + EUD_REG_CTL_OUT_1); + if (reg & BIT(6)) + chip->chgr_enable = true; + else + chip->chgr_enable = false; + + schedule_work(&chip->eud_work); + + /* set and clear chgr_int_clr[0] to clear interrupt */ + writel_relaxed(BIT(0), chip->eud_reg_base + EUD_REG_CHGR_INT_CLR); + /* Ensure Register Writes Complete */ + wmb(); + writel_relaxed(0, chip->eud_reg_base + EUD_REG_CHGR_INT_CLR); +} + +static void pet_eud(struct eud_chip *chip) +{ + u32 reg; + + /* read sw_attach_det[0] to find attach/detach event */ + reg = readl_relaxed(chip->eud_reg_base + EUD_REG_SW_ATTACH_DET); + if (reg & BIT(0)) { + /* Detach & Attach pet for EUD */ + writel_relaxed(0, chip->eud_reg_base + EUD_REG_SW_ATTACH_DET); + /* Ensure Register Writes Complete */ + wmb(); + /* Delay to make sure detach pet is done before attach pet */ + udelay(100); + writel_relaxed(BIT(0), chip->eud_reg_base + + EUD_REG_SW_ATTACH_DET); + /* Ensure Register Writes Complete */ + wmb(); + } else { + /* Attach pet for EUD */ + writel_relaxed(BIT(0), chip->eud_reg_base + + EUD_REG_SW_ATTACH_DET); + /* Ensure Register Writes Complete */ + wmb(); + } +} + +static irqreturn_t handle_eud_irq(int irq, void *data) +{ + struct eud_chip *chip = data; + u32 reg; + + /* read status register and find out which interrupt triggered */ + reg = readl_relaxed(chip->eud_reg_base + EUD_REG_INT_STATUS_1); + switch (reg & EUD_INT_ALL) { + case EUD_INT_VBUS: + chip->int_status = EUD_INT_VBUS; + usb_attach_detach(chip); + break; + case EUD_INT_CHGR: + chip->int_status = EUD_INT_CHGR; + chgr_enable_disable(chip); + break; + case EUD_INT_SAFE_MODE: + pet_eud(chip); + break; + default: + return IRQ_NONE; + } + return IRQ_HANDLED; +} + +static int msm_eud_probe(struct platform_device *pdev) +{ + struct eud_chip *chip; + struct resource *res; + int ret; + + chip = devm_kzalloc(&pdev->dev, sizeof(*chip), GFP_KERNEL); + if (!chip) + return -ENOMEM; + + chip->dev = &pdev->dev; + platform_set_drvdata(pdev, chip); + + ret = device_create_file(&pdev->dev, &eud_attribute); + if (ret) + return ret; + + chip->extcon = devm_extcon_dev_allocate(&pdev->dev, eud_extcon_cable); + if (IS_ERR(chip->extcon)) + return PTR_ERR(chip->extcon); + + ret = devm_extcon_dev_register(&pdev->dev, chip->extcon); + if (ret) + return ret; + + res = platform_get_resource(pdev, IORESOURCE_MEM, 0); + if (!res) + return -ENOMEM; + + chip->eud_reg_base = devm_ioremap_resource(&pdev->dev, res); + if (IS_ERR(chip->eud_reg_base)) + return PTR_ERR(chip->eud_reg_base); + + chip->eud_irq = platform_get_irq(pdev, 0); + + ret = devm_request_irq(&pdev->dev, chip->eud_irq, handle_eud_irq, + IRQF_TRIGGER_HIGH, NULL, chip); + if (ret) + return ret; + + device_init_wakeup(&pdev->dev, true); + enable_irq_wake(chip->eud_irq); + + INIT_WORK(&chip->eud_work, eud_event_notifier); + + if (ret) + return ret; + + /* Enable EUD */ + if (chip->enable) + enable_eud(chip); + + return 0; +} + +static int msm_eud_remove(struct platform_device *pdev) +{ + struct eud_chip *chip = platform_get_drvdata(pdev); + + if (chip->enable) + disable_eud(chip); + device_remove_file(&pdev->dev, &eud_attribute); + device_init_wakeup(&pdev->dev, false); + disable_irq_wake(chip->eud_irq); + + return 0; +} + +static const struct of_device_id msm_eud_dt_match[] = { + {.compatible = "qcom,msm-eud"}, + {}, +}; +MODULE_DEVICE_TABLE(of, msm_eud_dt_match); + +static struct platform_driver msm_eud_driver = { + .probe = msm_eud_probe, + .remove = msm_eud_remove, + .driver = { + .name = "msm-eud", + .of_match_table = msm_eud_dt_match, + }, +}; +module_platform_driver(msm_eud_driver); + +MODULE_DESCRIPTION("QTI EUD driver"); +MODULE_LICENSE("GPL v2"); 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