diff options
Diffstat (limited to '')
-rw-r--r-- | drivers/usb/cdns3/drd.c | 495 |
1 files changed, 495 insertions, 0 deletions
diff --git a/drivers/usb/cdns3/drd.c b/drivers/usb/cdns3/drd.c new file mode 100644 index 000000000..d00ff98df --- /dev/null +++ b/drivers/usb/cdns3/drd.c @@ -0,0 +1,495 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * Cadence USBSS and USBSSP DRD Driver. + * + * Copyright (C) 2018-2020 Cadence. + * Copyright (C) 2019 Texas Instruments + * + * Author: Pawel Laszczak <pawell@cadence.com> + * Roger Quadros <rogerq@ti.com> + * + */ +#include <linux/kernel.h> +#include <linux/interrupt.h> +#include <linux/delay.h> +#include <linux/iopoll.h> +#include <linux/usb/otg.h> + +#include "drd.h" +#include "core.h" + +/** + * cdns_set_mode - change mode of OTG Core + * @cdns: pointer to context structure + * @mode: selected mode from cdns_role + * + * Returns 0 on success otherwise negative errno + */ +static int cdns_set_mode(struct cdns *cdns, enum usb_dr_mode mode) +{ + void __iomem *override_reg; + u32 reg; + + switch (mode) { + case USB_DR_MODE_PERIPHERAL: + break; + case USB_DR_MODE_HOST: + break; + case USB_DR_MODE_OTG: + dev_dbg(cdns->dev, "Set controller to OTG mode\n"); + + if (cdns->version == CDNSP_CONTROLLER_V2) + override_reg = &cdns->otg_cdnsp_regs->override; + else if (cdns->version == CDNS3_CONTROLLER_V1) + override_reg = &cdns->otg_v1_regs->override; + else + override_reg = &cdns->otg_v0_regs->ctrl1; + + reg = readl(override_reg); + + if (cdns->version != CDNS3_CONTROLLER_V0) + reg |= OVERRIDE_IDPULLUP; + else + reg |= OVERRIDE_IDPULLUP_V0; + + writel(reg, override_reg); + + if (cdns->version == CDNS3_CONTROLLER_V1) { + /* + * Enable work around feature built into the + * controller to address issue with RX Sensitivity + * est (EL_17) for USB2 PHY. The issue only occures + * for 0x0002450D controller version. + */ + if (cdns->phyrst_a_enable) { + reg = readl(&cdns->otg_v1_regs->phyrst_cfg); + reg |= PHYRST_CFG_PHYRST_A_ENABLE; + writel(reg, &cdns->otg_v1_regs->phyrst_cfg); + } + } + + /* + * Hardware specification says: "ID_VALUE must be valid within + * 50ms after idpullup is set to '1" so driver must wait + * 50ms before reading this pin. + */ + usleep_range(50000, 60000); + break; + default: + dev_err(cdns->dev, "Unsupported mode of operation %d\n", mode); + return -EINVAL; + } + + return 0; +} + +int cdns_get_id(struct cdns *cdns) +{ + int id; + + id = readl(&cdns->otg_regs->sts) & OTGSTS_ID_VALUE; + dev_dbg(cdns->dev, "OTG ID: %d", id); + + return id; +} + +int cdns_get_vbus(struct cdns *cdns) +{ + int vbus; + + vbus = !!(readl(&cdns->otg_regs->sts) & OTGSTS_VBUS_VALID); + dev_dbg(cdns->dev, "OTG VBUS: %d", vbus); + + return vbus; +} + +void cdns_clear_vbus(struct cdns *cdns) +{ + u32 reg; + + if (cdns->version != CDNSP_CONTROLLER_V2) + return; + + reg = readl(&cdns->otg_cdnsp_regs->override); + reg |= OVERRIDE_SESS_VLD_SEL; + writel(reg, &cdns->otg_cdnsp_regs->override); +} +EXPORT_SYMBOL_GPL(cdns_clear_vbus); + +void cdns_set_vbus(struct cdns *cdns) +{ + u32 reg; + + if (cdns->version != CDNSP_CONTROLLER_V2) + return; + + reg = readl(&cdns->otg_cdnsp_regs->override); + reg &= ~OVERRIDE_SESS_VLD_SEL; + writel(reg, &cdns->otg_cdnsp_regs->override); +} +EXPORT_SYMBOL_GPL(cdns_set_vbus); + +bool cdns_is_host(struct cdns *cdns) +{ + if (cdns->dr_mode == USB_DR_MODE_HOST) + return true; + else if (cdns_get_id(cdns) == CDNS3_ID_HOST) + return true; + + return false; +} + +bool cdns_is_device(struct cdns *cdns) +{ + if (cdns->dr_mode == USB_DR_MODE_PERIPHERAL) + return true; + else if (cdns->dr_mode == USB_DR_MODE_OTG) + if (cdns_get_id(cdns) == CDNS3_ID_PERIPHERAL) + return true; + + return false; +} + +/** + * cdns_otg_disable_irq - Disable all OTG interrupts + * @cdns: Pointer to controller context structure + */ +static void cdns_otg_disable_irq(struct cdns *cdns) +{ + writel(0, &cdns->otg_irq_regs->ien); +} + +/** + * cdns_otg_enable_irq - enable id and sess_valid interrupts + * @cdns: Pointer to controller context structure + */ +static void cdns_otg_enable_irq(struct cdns *cdns) +{ + writel(OTGIEN_ID_CHANGE_INT | OTGIEN_VBUSVALID_RISE_INT | + OTGIEN_VBUSVALID_FALL_INT, &cdns->otg_irq_regs->ien); +} + +/** + * cdns_drd_host_on - start host. + * @cdns: Pointer to controller context structure. + * + * Returns 0 on success otherwise negative errno. + */ +int cdns_drd_host_on(struct cdns *cdns) +{ + u32 val, ready_bit; + int ret; + + /* Enable host mode. */ + writel(OTGCMD_HOST_BUS_REQ | OTGCMD_OTG_DIS, + &cdns->otg_regs->cmd); + + if (cdns->version == CDNSP_CONTROLLER_V2) + ready_bit = OTGSTS_CDNSP_XHCI_READY; + else + ready_bit = OTGSTS_CDNS3_XHCI_READY; + + dev_dbg(cdns->dev, "Waiting till Host mode is turned on\n"); + ret = readl_poll_timeout_atomic(&cdns->otg_regs->sts, val, + val & ready_bit, 1, 100000); + + if (ret) + dev_err(cdns->dev, "timeout waiting for xhci_ready\n"); + + phy_set_mode(cdns->usb3_phy, PHY_MODE_USB_HOST); + return ret; +} + +/** + * cdns_drd_host_off - stop host. + * @cdns: Pointer to controller context structure. + */ +void cdns_drd_host_off(struct cdns *cdns) +{ + u32 val; + + writel(OTGCMD_HOST_BUS_DROP | OTGCMD_DEV_BUS_DROP | + OTGCMD_DEV_POWER_OFF | OTGCMD_HOST_POWER_OFF, + &cdns->otg_regs->cmd); + + /* Waiting till H_IDLE state.*/ + readl_poll_timeout_atomic(&cdns->otg_regs->state, val, + !(val & OTGSTATE_HOST_STATE_MASK), + 1, 2000000); + phy_set_mode(cdns->usb3_phy, PHY_MODE_INVALID); +} + +/** + * cdns_drd_gadget_on - start gadget. + * @cdns: Pointer to controller context structure. + * + * Returns 0 on success otherwise negative errno + */ +int cdns_drd_gadget_on(struct cdns *cdns) +{ + u32 reg = OTGCMD_OTG_DIS; + u32 ready_bit; + int ret, val; + + /* switch OTG core */ + writel(OTGCMD_DEV_BUS_REQ | reg, &cdns->otg_regs->cmd); + + dev_dbg(cdns->dev, "Waiting till Device mode is turned on\n"); + + if (cdns->version == CDNSP_CONTROLLER_V2) + ready_bit = OTGSTS_CDNSP_DEV_READY; + else + ready_bit = OTGSTS_CDNS3_DEV_READY; + + ret = readl_poll_timeout_atomic(&cdns->otg_regs->sts, val, + val & ready_bit, 1, 100000); + if (ret) { + dev_err(cdns->dev, "timeout waiting for dev_ready\n"); + return ret; + } + + phy_set_mode(cdns->usb3_phy, PHY_MODE_USB_DEVICE); + return 0; +} +EXPORT_SYMBOL_GPL(cdns_drd_gadget_on); + +/** + * cdns_drd_gadget_off - stop gadget. + * @cdns: Pointer to controller context structure. + */ +void cdns_drd_gadget_off(struct cdns *cdns) +{ + u32 val; + + /* + * Driver should wait at least 10us after disabling Device + * before turning-off Device (DEV_BUS_DROP). + */ + usleep_range(20, 30); + writel(OTGCMD_HOST_BUS_DROP | OTGCMD_DEV_BUS_DROP | + OTGCMD_DEV_POWER_OFF | OTGCMD_HOST_POWER_OFF, + &cdns->otg_regs->cmd); + /* Waiting till DEV_IDLE state.*/ + readl_poll_timeout_atomic(&cdns->otg_regs->state, val, + !(val & OTGSTATE_DEV_STATE_MASK), + 1, 2000000); + phy_set_mode(cdns->usb3_phy, PHY_MODE_INVALID); +} +EXPORT_SYMBOL_GPL(cdns_drd_gadget_off); + +/** + * cdns_init_otg_mode - initialize drd controller + * @cdns: Pointer to controller context structure + * + * Returns 0 on success otherwise negative errno + */ +static int cdns_init_otg_mode(struct cdns *cdns) +{ + int ret; + + cdns_otg_disable_irq(cdns); + /* clear all interrupts */ + writel(~0, &cdns->otg_irq_regs->ivect); + + ret = cdns_set_mode(cdns, USB_DR_MODE_OTG); + if (ret) + return ret; + + cdns_otg_enable_irq(cdns); + + return 0; +} + +/** + * cdns_drd_update_mode - initialize mode of operation + * @cdns: Pointer to controller context structure + * + * Returns 0 on success otherwise negative errno + */ +int cdns_drd_update_mode(struct cdns *cdns) +{ + int ret; + + switch (cdns->dr_mode) { + case USB_DR_MODE_PERIPHERAL: + ret = cdns_set_mode(cdns, USB_DR_MODE_PERIPHERAL); + break; + case USB_DR_MODE_HOST: + ret = cdns_set_mode(cdns, USB_DR_MODE_HOST); + break; + case USB_DR_MODE_OTG: + ret = cdns_init_otg_mode(cdns); + break; + default: + dev_err(cdns->dev, "Unsupported mode of operation %d\n", + cdns->dr_mode); + return -EINVAL; + } + + return ret; +} + +static irqreturn_t cdns_drd_thread_irq(int irq, void *data) +{ + struct cdns *cdns = data; + + cdns_hw_role_switch(cdns); + + return IRQ_HANDLED; +} + +/** + * cdns_drd_irq - interrupt handler for OTG events + * + * @irq: irq number for cdns core device + * @data: structure of cdns + * + * Returns IRQ_HANDLED or IRQ_NONE + */ +static irqreturn_t cdns_drd_irq(int irq, void *data) +{ + irqreturn_t ret = IRQ_NONE; + struct cdns *cdns = data; + u32 reg; + + if (cdns->dr_mode != USB_DR_MODE_OTG) + return IRQ_NONE; + + if (cdns->in_lpm) + return ret; + + reg = readl(&cdns->otg_irq_regs->ivect); + + if (!reg) + return IRQ_NONE; + + if (reg & OTGIEN_ID_CHANGE_INT) { + dev_dbg(cdns->dev, "OTG IRQ: new ID: %d\n", + cdns_get_id(cdns)); + + ret = IRQ_WAKE_THREAD; + } + + if (reg & (OTGIEN_VBUSVALID_RISE_INT | OTGIEN_VBUSVALID_FALL_INT)) { + dev_dbg(cdns->dev, "OTG IRQ: new VBUS: %d\n", + cdns_get_vbus(cdns)); + + ret = IRQ_WAKE_THREAD; + } + + writel(~0, &cdns->otg_irq_regs->ivect); + return ret; +} + +int cdns_drd_init(struct cdns *cdns) +{ + void __iomem *regs; + u32 state; + int ret; + + regs = devm_ioremap_resource(cdns->dev, &cdns->otg_res); + if (IS_ERR(regs)) + return PTR_ERR(regs); + + /* Detection of DRD version. Controller has been released + * in three versions. All are very similar and are software compatible, + * but they have same changes in register maps. + * The first register in oldest version is command register and it's + * read only. Driver should read 0 from it. On the other hand, in v1 + * and v2 the first register contains device ID number which is not + * set to 0. Driver uses this fact to detect the proper version of + * controller. + */ + cdns->otg_v0_regs = regs; + if (!readl(&cdns->otg_v0_regs->cmd)) { + cdns->version = CDNS3_CONTROLLER_V0; + cdns->otg_v1_regs = NULL; + cdns->otg_cdnsp_regs = NULL; + cdns->otg_regs = regs; + cdns->otg_irq_regs = (struct cdns_otg_irq_regs __iomem *) + &cdns->otg_v0_regs->ien; + writel(1, &cdns->otg_v0_regs->simulate); + dev_dbg(cdns->dev, "DRD version v0 (%08x)\n", + readl(&cdns->otg_v0_regs->version)); + } else { + cdns->otg_v0_regs = NULL; + cdns->otg_v1_regs = regs; + cdns->otg_cdnsp_regs = regs; + + cdns->otg_regs = (void __iomem *)&cdns->otg_v1_regs->cmd; + + if (readl(&cdns->otg_cdnsp_regs->did) == OTG_CDNSP_DID) { + cdns->otg_irq_regs = (struct cdns_otg_irq_regs __iomem *) + &cdns->otg_cdnsp_regs->ien; + cdns->version = CDNSP_CONTROLLER_V2; + } else { + cdns->otg_irq_regs = (struct cdns_otg_irq_regs __iomem *) + &cdns->otg_v1_regs->ien; + writel(1, &cdns->otg_v1_regs->simulate); + cdns->version = CDNS3_CONTROLLER_V1; + } + + dev_dbg(cdns->dev, "DRD version v1 (ID: %08x, rev: %08x)\n", + readl(&cdns->otg_v1_regs->did), + readl(&cdns->otg_v1_regs->rid)); + } + + state = OTGSTS_STRAP(readl(&cdns->otg_regs->sts)); + + /* Update dr_mode according to STRAP configuration. */ + cdns->dr_mode = USB_DR_MODE_OTG; + + if ((cdns->version == CDNSP_CONTROLLER_V2 && + state == OTGSTS_CDNSP_STRAP_HOST) || + (cdns->version != CDNSP_CONTROLLER_V2 && + state == OTGSTS_STRAP_HOST)) { + dev_dbg(cdns->dev, "Controller strapped to HOST\n"); + cdns->dr_mode = USB_DR_MODE_HOST; + } else if ((cdns->version == CDNSP_CONTROLLER_V2 && + state == OTGSTS_CDNSP_STRAP_GADGET) || + (cdns->version != CDNSP_CONTROLLER_V2 && + state == OTGSTS_STRAP_GADGET)) { + dev_dbg(cdns->dev, "Controller strapped to PERIPHERAL\n"); + cdns->dr_mode = USB_DR_MODE_PERIPHERAL; + } + + ret = devm_request_threaded_irq(cdns->dev, cdns->otg_irq, + cdns_drd_irq, + cdns_drd_thread_irq, + IRQF_SHARED, + dev_name(cdns->dev), cdns); + if (ret) { + dev_err(cdns->dev, "couldn't get otg_irq\n"); + return ret; + } + + state = readl(&cdns->otg_regs->sts); + if (OTGSTS_OTG_NRDY(state)) { + dev_err(cdns->dev, "Cadence USB3 OTG device not ready\n"); + return -ENODEV; + } + + return 0; +} + +int cdns_drd_exit(struct cdns *cdns) +{ + cdns_otg_disable_irq(cdns); + + return 0; +} + + +/* Indicate the cdns3 core was power lost before */ +bool cdns_power_is_lost(struct cdns *cdns) +{ + if (cdns->version == CDNS3_CONTROLLER_V0) { + if (!(readl(&cdns->otg_v0_regs->simulate) & BIT(0))) + return true; + } else { + if (!(readl(&cdns->otg_v1_regs->simulate) & BIT(0))) + return true; + } + return false; +} +EXPORT_SYMBOL_GPL(cdns_power_is_lost); |