diff options
Diffstat (limited to 'drivers/usb/isp1760/isp1760-udc.c')
| -rw-r--r-- | drivers/usb/isp1760/isp1760-udc.c | 1498 |
1 files changed, 1498 insertions, 0 deletions
diff --git a/drivers/usb/isp1760/isp1760-udc.c b/drivers/usb/isp1760/isp1760-udc.c new file mode 100644 index 00000000000..9612d799056 --- /dev/null +++ b/drivers/usb/isp1760/isp1760-udc.c @@ -0,0 +1,1498 @@ +/* + * Driver for the NXP ISP1761 device controller + * + * Copyright 2014 Ideas on Board Oy + * + * Contacts: + * Laurent Pinchart <laurent.pinchart@ideasonboard.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. + */ + +#include <linux/interrupt.h> +#include <linux/io.h> +#include <linux/kernel.h> +#include <linux/list.h> +#include <linux/module.h> +#include <linux/slab.h> +#include <linux/timer.h> +#include <linux/usb.h> + +#include "isp1760-core.h" +#include "isp1760-regs.h" +#include "isp1760-udc.h" + +#define ISP1760_VBUS_POLL_INTERVAL msecs_to_jiffies(500) + +struct isp1760_request { + struct usb_request req; + struct list_head queue; + struct isp1760_ep *ep; + unsigned int packet_size; +}; + +static inline struct isp1760_udc *gadget_to_udc(struct usb_gadget *gadget) +{ + return container_of(gadget, struct isp1760_udc, gadget); +} + +static inline struct isp1760_ep *ep_to_udc_ep(struct usb_ep *ep) +{ + return container_of(ep, struct isp1760_ep, ep); +} + +static inline struct isp1760_request *req_to_udc_req(struct usb_request *req) +{ + return container_of(req, struct isp1760_request, req); +} + +static inline u32 isp1760_udc_read(struct isp1760_udc *udc, u16 reg) +{ + return isp1760_read32(udc->regs, reg); +} + +static inline void isp1760_udc_write(struct isp1760_udc *udc, u16 reg, u32 val) +{ + isp1760_write32(udc->regs, reg, val); +} + +/* ----------------------------------------------------------------------------- + * Endpoint Management + */ + +static struct isp1760_ep *isp1760_udc_find_ep(struct isp1760_udc *udc, + u16 index) +{ + unsigned int i; + + if (index == 0) + return &udc->ep[0]; + + for (i = 1; i < ARRAY_SIZE(udc->ep); ++i) { + if (udc->ep[i].addr == index) + return udc->ep[i].desc ? &udc->ep[i] : NULL; + } + + return NULL; +} + +static void __isp1760_udc_select_ep(struct isp1760_ep *ep, int dir) +{ + isp1760_udc_write(ep->udc, DC_EPINDEX, + DC_ENDPIDX(ep->addr & USB_ENDPOINT_NUMBER_MASK) | + (dir == USB_DIR_IN ? DC_EPDIR : 0)); +} + +/** + * isp1760_udc_select_ep - Select an endpoint for register access + * @ep: The endpoint + * + * The ISP1761 endpoint registers are banked. This function selects the target + * endpoint for banked register access. The selection remains valid until the + * next call to this function, the next direct access to the EPINDEX register + * or the next reset, whichever comes first. + * + * Called with the UDC spinlock held. + */ +static void isp1760_udc_select_ep(struct isp1760_ep *ep) +{ + __isp1760_udc_select_ep(ep, ep->addr & USB_ENDPOINT_DIR_MASK); +} + +/* Called with the UDC spinlock held. */ +static void isp1760_udc_ctrl_send_status(struct isp1760_ep *ep, int dir) +{ + struct isp1760_udc *udc = ep->udc; + + /* + * Proceed to the status stage. The status stage data packet flows in + * the direction opposite to the data stage data packets, we thus need + * to select the OUT/IN endpoint for IN/OUT transfers. + */ + isp1760_udc_write(udc, DC_EPINDEX, DC_ENDPIDX(0) | + (dir == USB_DIR_IN ? 0 : DC_EPDIR)); + isp1760_udc_write(udc, DC_CTRLFUNC, DC_STATUS); + + /* + * The hardware will terminate the request automatically and go back to + * the setup stage without notifying us. + */ + udc->ep0_state = ISP1760_CTRL_SETUP; +} + +/* Called without the UDC spinlock held. */ +static void isp1760_udc_request_complete(struct isp1760_ep *ep, + struct isp1760_request *req, + int status) +{ + struct isp1760_udc *udc = ep->udc; + unsigned long flags; + + dev_dbg(ep->udc->isp->dev, "completing request %p with status %d\n", + req, status); + + req->ep = NULL; + req->req.status = status; + req->req.complete(&ep->ep, &req->req); + + spin_lock_irqsave(&udc->lock, flags); + + /* + * When completing control OUT requests, move to the status stage after + * calling the request complete callback. This gives the gadget an + * opportunity to stall the control transfer if needed. + */ + if (status == 0 && ep->addr == 0 && udc->ep0_dir == USB_DIR_OUT) + isp1760_udc_ctrl_send_status(ep, USB_DIR_OUT); + + spin_unlock_irqrestore(&udc->lock, flags); +} + +static void isp1760_udc_ctrl_send_stall(struct isp1760_ep *ep) +{ + struct isp1760_udc *udc = ep->udc; + unsigned long flags; + + dev_dbg(ep->udc->isp->dev, "%s(ep%02x)\n", __func__, ep->addr); + + spin_lock_irqsave(&udc->lock, flags); + + /* Stall both the IN and OUT endpoints. */ + __isp1760_udc_select_ep(ep, USB_DIR_OUT); + isp1760_udc_write(udc, DC_CTRLFUNC, DC_STALL); + __isp1760_udc_select_ep(ep, USB_DIR_IN); + isp1760_udc_write(udc, DC_CTRLFUNC, DC_STALL); + + /* A protocol stall completes the control transaction. */ + udc->ep0_state = ISP1760_CTRL_SETUP; + + spin_unlock_irqrestore(&udc->lock, flags); +} + +/* ----------------------------------------------------------------------------- + * Data Endpoints + */ + +/* Called with the UDC spinlock held. */ +static bool isp1760_udc_receive(struct isp1760_ep *ep, + struct isp1760_request *req) +{ + struct isp1760_udc *udc = ep->udc; + unsigned int len; + u32 *buf; + int i; + + isp1760_udc_select_ep(ep); + len = isp1760_udc_read(udc, DC_BUFLEN) & DC_DATACOUNT_MASK; + + dev_dbg(udc->isp->dev, "%s: received %u bytes (%u/%u done)\n", + __func__, len, req->req.actual, req->req.length); + + len = min(len, req->req.length - req->req.actual); + + if (!len) { + /* + * There's no data to be read from the FIFO, acknowledge the RX + * interrupt by clearing the buffer. + * + * TODO: What if another packet arrives in the meantime ? The + * datasheet doesn't clearly document how this should be + * handled. + */ + isp1760_udc_write(udc, DC_CTRLFUNC, DC_CLBUF); + return false; + } + + buf = req->req.buf + req->req.actual; + + /* + * Make sure not to read more than one extra byte, otherwise data from + * the next packet might be removed from the FIFO. + */ + for (i = len; i > 2; i -= 4, ++buf) + *buf = le32_to_cpu(isp1760_udc_read(udc, DC_DATAPORT)); + if (i > 0) + *(u16 *)buf = le16_to_cpu(readw(udc->regs + DC_DATAPORT)); + + req->req.actual += len; + + /* + * TODO: The short_not_ok flag isn't supported yet, but isn't used by + * any gadget driver either. + */ + + dev_dbg(udc->isp->dev, + "%s: req %p actual/length %u/%u maxpacket %u packet size %u\n", + __func__, req, req->req.actual, req->req.length, ep->maxpacket, + len); + + ep->rx_pending = false; + + /* + * Complete the request if all data has been received or if a short + * packet has been received. + */ + if (req->req.actual == req->req.length || len < ep->maxpacket) { + list_del(&req->queue); + return true; + } + + return false; +} + +static void isp1760_udc_transmit(struct isp1760_ep *ep, + struct isp1760_request *req) +{ + struct isp1760_udc *udc = ep->udc; + u32 *buf = req->req.buf + req->req.actual; + int i; + + req->packet_size = min(req->req.length - req->req.actual, + ep->maxpacket); + + dev_dbg(udc->isp->dev, "%s: transferring %u bytes (%u/%u done)\n", + __func__, req->packet_size, req->req.actual, + req->req.length); + + __isp1760_udc_select_ep(ep, USB_DIR_IN); + + if (req->packet_size) + isp1760_udc_write(udc, DC_BUFLEN, req->packet_size); + + /* + * Make sure not to write more than one extra byte, otherwise extra data + * will stay in the FIFO and will be transmitted during the next control + * request. The endpoint control CLBUF bit is supposed to allow flushing + * the FIFO for this kind of conditions, but doesn't seem to work. + */ + for (i = req->packet_size; i > 2; i -= 4, ++buf) + isp1760_udc_write(udc, DC_DATAPORT, cpu_to_le32(*buf)); + if (i > 0) + writew(cpu_to_le16(*(u16 *)buf), udc->regs + DC_DATAPORT); + + if (ep->addr == 0) + isp1760_udc_write(udc, DC_CTRLFUNC, DC_DSEN); + if (!req->packet_size) + isp1760_udc_write(udc, DC_CTRLFUNC, DC_VENDP); +} + +static void isp1760_ep_rx_ready(struct isp1760_ep *ep) +{ + struct isp1760_udc *udc = ep->udc; + struct isp1760_request *req; + bool complete; + + spin_lock(&udc->lock); + + if (ep->addr == 0 && udc->ep0_state != ISP1760_CTRL_DATA_OUT) { + spin_unlock(&udc->lock); + dev_dbg(udc->isp->dev, "%s: invalid ep0 state %u\n", __func__, + udc->ep0_state); + return; + } + + if (ep->addr != 0 && !ep->desc) { + spin_unlock(&udc->lock); + dev_dbg(udc->isp->dev, "%s: ep%02x is disabled\n", __func__, + ep->addr); + return; + } + + if (list_empty(&ep->queue)) { + ep->rx_pending = true; + spin_unlock(&udc->lock); + dev_dbg(udc->isp->dev, "%s: ep%02x (%p) has no request queued\n", + __func__, ep->addr, ep); + return; + } + + req = list_first_entry(&ep->queue, struct isp1760_request, + queue); + complete = isp1760_udc_receive(ep, req); + + spin_unlock(&udc->lock); + + if (complete) + isp1760_udc_request_complete(ep, req, 0); +} + +static void isp1760_ep_tx_complete(struct isp1760_ep *ep) +{ + struct isp1760_udc *udc = ep->udc; + struct isp1760_request *complete = NULL; + struct isp1760_request *req; + bool need_zlp; + + spin_lock(&udc->lock); + + if (ep->addr == 0 && udc->ep0_state != ISP1760_CTRL_DATA_IN) { + spin_unlock(&udc->lock); + dev_dbg(udc->isp->dev, "TX IRQ: invalid endpoint state %u\n", + udc->ep0_state); + return; + } + + if (list_empty(&ep->queue)) { + /* + * This can happen for the control endpoint when the reply to + * the GET_STATUS IN control request is sent directly by the + * setup IRQ handler. Just proceed to the status stage. + */ + if (ep->addr == 0) { + isp1760_udc_ctrl_send_status(ep, USB_DIR_IN); + spin_unlock(&udc->lock); + return; + } + + spin_unlock(&udc->lock); + dev_dbg(udc->isp->dev, "%s: ep%02x has no request queued\n", + __func__, ep->addr); + return; + } + + req = list_first_entry(&ep->queue, struct isp1760_request, + queue); + req->req.actual += req->packet_size; + + need_zlp = req->req.actual == req->req.length && + !(req->req.length % ep->maxpacket) && + req->packet_size && req->req.zero; + + dev_dbg(udc->isp->dev, + "TX IRQ: req %p actual/length %u/%u maxpacket %u packet size %u zero %u need zlp %u\n", + req, req->req.actual, req->req.length, ep->maxpacket, + req->packet_size, req->req.zero, need_zlp); + + /* + * Complete the request if all data has been sent and we don't need to + * transmit a zero length packet. + */ + if (req->req.actual == req->req.length && !need_zlp) { + complete = req; + list_del(&req->queue); + + if (ep->addr == 0) + isp1760_udc_ctrl_send_status(ep, USB_DIR_IN); + + if (!list_empty(&ep->queue)) + req = list_first_entry(&ep->queue, + struct isp1760_request, queue); + else + req = NULL; + } + + /* + * Transmit the next packet or start the next request, if any. + * + * TODO: If the endpoint is stalled the next request shouldn't be + * started, but what about the next packet ? + */ + if (req) + isp1760_udc_transmit(ep, req); + + spin_unlock(&udc->lock); + + if (complete) + isp1760_udc_request_complete(ep, complete, 0); +} + +static int __isp1760_udc_set_halt(struct isp1760_ep *ep, bool halt) +{ + struct isp1760_udc *udc = ep->udc; + + dev_dbg(udc->isp->dev, "%s: %s halt on ep%02x\n", __func__, + halt ? "set" : "clear", ep->addr); + + if (ep->desc && usb_endpoint_xfer_isoc(ep->desc)) { + dev_dbg(udc->isp->dev, "%s: ep%02x is isochronous\n", __func__, + ep->addr); + return -EINVAL; + } + + isp1760_udc_select_ep(ep); + isp1760_udc_write(udc, DC_CTRLFUNC, halt ? DC_STALL : 0); + + if (ep->addr == 0) { + /* When halting the control endpoint, stall both IN and OUT. */ + __isp1760_udc_select_ep(ep, USB_DIR_IN); + isp1760_udc_write(udc, DC_CTRLFUNC, halt ? DC_STALL : 0); + } else if (!halt) { + /* Reset the data PID by cycling the endpoint enable bit. */ + u16 eptype = isp1760_udc_read(udc, DC_EPTYPE); + + isp1760_udc_write(udc, DC_EPTYPE, eptype & ~DC_EPENABLE); + isp1760_udc_write(udc, DC_EPTYPE, eptype); + + /* + * Disabling the endpoint emptied the transmit FIFO, fill it + * again if a request is pending. + * + * TODO: Does the gadget framework require synchronizatino with + * the TX IRQ handler ? + */ + if ((ep->addr & USB_DIR_IN) && !list_empty(&ep->queue)) { + struct isp1760_request *req; + + req = list_first_entry(&ep->queue, + struct isp1760_request, queue); + isp1760_udc_transmit(ep, req); + } + } + + ep->halted = halt; + + return 0; +} + +/* ----------------------------------------------------------------------------- + * Control Endpoint + */ + +static int isp1760_udc_get_status(struct isp1760_udc *udc, + const struct usb_ctrlrequest *req) +{ + struct isp1760_ep *ep; + u16 status; + + if (req->wLength != cpu_to_le16(2) || req->wValue != cpu_to_le16(0)) + return -EINVAL; + + switch (req->bRequestType) { + case USB_DIR_IN | USB_RECIP_DEVICE: + status = udc->devstatus; + break; + + case USB_DIR_IN | USB_RECIP_INTERFACE: + status = 0; + break; + + case USB_DIR_IN | USB_RECIP_ENDPOINT: + ep = isp1760_udc_find_ep(udc, le16_to_cpu(req->wIndex)); + if (!ep) + return -EINVAL; + + status = 0; + if (ep->halted) + status |= 1 << USB_ENDPOINT_HALT; + break; + + default: + return -EINVAL; + } + + isp1760_udc_write(udc, DC_EPINDEX, DC_ENDPIDX(0) | DC_EPDIR); + isp1760_udc_write(udc, DC_BUFLEN, 2); + + writew(cpu_to_le16(status), udc->regs + DC_DATAPORT); + + isp1760_udc_write(udc, DC_CTRLFUNC, DC_DSEN); + + dev_dbg(udc->isp->dev, "%s: status 0x%04x\n", __func__, status); + + return 0; +} + +static int isp1760_udc_set_address(struct isp1760_udc *udc, u16 addr) +{ + if (addr > 127) { + dev_dbg(udc->isp->dev, "invalid device address %u\n", addr); + return -EINVAL; + } + + if (udc->gadget.state != USB_STATE_DEFAULT && + udc->gadget.state != USB_STATE_ADDRESS) { + dev_dbg(udc->isp->dev, "can't set address in state %u\n", + udc->gadget.state); + return -EINVAL; + } + + usb_gadget_set_state(&udc->gadget, addr ? USB_STATE_ADDRESS : + USB_STATE_DEFAULT); + + isp1760_udc_write(udc, DC_ADDRESS, DC_DEVEN | addr); + + spin_lock(&udc->lock); + isp1760_udc_ctrl_send_status(&udc->ep[0], USB_DIR_OUT); + spin_unlock(&udc->lock); + + return 0; +} + +static bool isp1760_ep0_setup_standard(struct isp1760_udc *udc, + struct usb_ctrlrequest *req) +{ + bool stall; + + switch (req->bRequest) { + case USB_REQ_GET_STATUS: + return isp1760_udc_get_status(udc, req); + + case USB_REQ_CLEAR_FEATURE: + switch (req->bRequestType) { + case USB_DIR_OUT | USB_RECIP_DEVICE: { + /* TODO: Handle remote wakeup feature. */ + return true; + } + + case USB_DIR_OUT | USB_RECIP_ENDPOINT: { + u16 index = le16_to_cpu(req->wIndex); + struct isp1760_ep *ep; + + if (req->wLength != cpu_to_le16(0) || + req->wValue != cpu_to_le16(USB_ENDPOINT_HALT)) + return true; + + ep = isp1760_udc_find_ep(udc, index); + if (!ep) + return true; + + spin_lock(&udc->lock); + + /* + * If the endpoint is wedged only the gadget can clear + * the halt feature. Pretend success in that case, but + * keep the endpoint halted. + */ + if (!ep->wedged) + stall = __isp1760_udc_set_halt(ep, false); + else + stall = false; + + if (!stall) + isp1760_udc_ctrl_send_status(&udc->ep[0], + USB_DIR_OUT); + + spin_unlock(&udc->lock); + return stall; + } + + default: + return true; + } + break; + + case USB_REQ_SET_FEATURE: + switch (req->bRequestType) { + case USB_DIR_OUT | USB_RECIP_DEVICE: { + /* TODO: Handle remote wakeup and test mode features */ + return true; + } + + case USB_DIR_OUT | USB_RECIP_ENDPOINT: { + u16 index = le16_to_cpu(req->wIndex); + struct isp1760_ep *ep; + + if (req->wLength != cpu_to_le16(0) || + req->wValue != cpu_to_le16(USB_ENDPOINT_HALT)) + return true; + + ep = isp1760_udc_find_ep(udc, index); + if (!ep) + return true; + + spin_lock(&udc->lock); + + stall = __isp1760_udc_set_halt(ep, true); + if (!stall) + isp1760_udc_ctrl_send_status(&udc->ep[0], + USB_DIR_OUT); + + spin_unlock(&udc->lock); + return stall; + } + + default: + return true; + } + break; + + case USB_REQ_SET_ADDRESS: + if (req->bRequestType != (USB_DIR_OUT | USB_RECIP_DEVICE)) + return true; + + return isp1760_udc_set_address(udc, le16_to_cpu(req->wValue)); + + case USB_REQ_SET_CONFIGURATION: + if (req->bRequestType != (USB_DIR_OUT | USB_RECIP_DEVICE)) + return true; + + if (udc->gadget.state != USB_STATE_ADDRESS && + udc->gadget.state != USB_STATE_CONFIGURED) + return true; + + stall = udc->driver->setup(&udc->gadget, req) < 0; + if (stall) + return true; + + usb_gadget_set_state(&udc->gadget, req->wValue ? + USB_STATE_CONFIGURED : USB_STATE_ADDRESS); + + /* + * SET_CONFIGURATION (and SET_INTERFACE) must reset the halt + * feature on all endpoints. There is however no need to do so + * explicitly here as the gadget driver will disable and + * reenable endpoints, clearing the halt feature. + */ + return false; + + default: + return udc->driver->setup(&udc->gadget, req) < 0; + } +} + +static void isp1760_ep0_setup(struct isp1760_udc *udc) +{ + union { + struct usb_ctrlrequest r; + u32 data[2]; + } req; + unsigned int count; + bool stall = false; + + spin_lock(&udc->lock); + + isp1760_udc_write(udc, DC_EPINDEX, DC_EP0SETUP); + + count = isp1760_udc_read(udc, DC_BUFLEN) & DC_DATACOUNT_MASK; + if (count != sizeof(req)) { + spin_unlock(&udc->lock); + + dev_err(udc->isp->dev, "invalid length %u for setup packet\n", + count); + + isp1760_udc_ctrl_send_stall(&udc->ep[0]); + return; + } + + req.data[0] = isp1760_udc_read(udc, DC_DATAPORT); + req.data[1] = isp1760_udc_read(udc, DC_DATAPORT); + + if (udc->ep0_state != ISP1760_CTRL_SETUP) { + spin_unlock(&udc->lock); + dev_dbg(udc->isp->dev, "unexpected SETUP packet\n"); + return; + } + + /* Move to the data stage. */ + if (!req.r.wLength) + udc->ep0_state = ISP1760_CTRL_STATUS; + else if (req.r.bRequestType & USB_DIR_IN) + udc->ep0_state = ISP1760_CTRL_DATA_IN; + else + udc->ep0_state = ISP1760_CTRL_DATA_OUT; + + udc->ep0_dir = req.r.bRequestType & USB_DIR_IN; + udc->ep0_length = le16_to_cpu(req.r.wLength); + + spin_unlock(&udc->lock); + + dev_dbg(udc->isp->dev, + "%s: bRequestType 0x%02x bRequest 0x%02x wValue 0x%04x wIndex 0x%04x wLength 0x%04x\n", + __func__, req.r.bRequestType, req.r.bRequest, + le16_to_cpu(req.r.wValue), le16_to_cpu(req.r.wIndex), + le16_to_cpu(req.r.wLength)); + + if ((req.r.bRequestType & USB_TYPE_MASK) == USB_TYPE_STANDARD) + stall = isp1760_ep0_setup_standard(udc, &req.r); + else + stall = udc->driver->setup(&udc->gadget, &req.r) < 0; + + if (stall) + isp1760_udc_ctrl_send_stall(&udc->ep[0]); +} + +/* ----------------------------------------------------------------------------- + * Gadget Endpoint Operations + */ + +static int isp1760_ep_enable(struct usb_ep *ep, + const struct usb_endpoint_descriptor *desc) +{ + struct isp1760_ep *uep = ep_to_udc_ep(ep); + struct isp1760_udc *udc = uep->udc; + unsigned long flags; + unsigned int type; + + dev_dbg(uep->udc->isp->dev, "%s\n", __func__); + + /* + * Validate the descriptor. The control endpoint can't be enabled + * manually. + */ + if (desc->bDescriptorType != USB_DT_ENDPOINT || + desc->bEndpointAddress == 0 || + desc->bEndpointAddress != uep->addr || + le16_to_cpu(desc->wMaxPacketSize) > ep->maxpacket) { + dev_dbg(udc->isp->dev, + "%s: invalid descriptor type %u addr %02x ep addr %02x max packet size %u/%u\n", + __func__, desc->bDescriptorType, + desc->bEndpointAddress, uep->addr, + le16_to_cpu(desc->wMaxPacketSize), ep->maxpacket); + return -EINVAL; + } + + switch (usb_endpoint_type(desc)) { + case USB_ENDPOINT_XFER_ISOC: + type = DC_ENDPTYP_ISOC; + break; + case USB_ENDPOINT_XFER_BULK: + type = DC_ENDPTYP_BULK; + break; + case USB_ENDPOINT_XFER_INT: + type = DC_ENDPTYP_INTERRUPT; + break; + case USB_ENDPOINT_XFER_CONTROL: + default: + dev_dbg(udc->isp->dev, "%s: control endpoints unsupported\n", + __func__); + return -EINVAL; + } + + spin_lock_irqsave(&udc->lock, flags); + + uep->desc = desc; + uep->maxpacket = le16_to_cpu(desc->wMaxPacketSize); + uep->rx_pending = false; + uep->halted = false; + uep->wedged = false; + + isp1760_udc_select_ep(uep); + isp1760_udc_write(udc, DC_EPMAXPKTSZ, uep->maxpacket); + isp1760_udc_write(udc, DC_BUFLEN, uep->maxpacket); + isp1760_udc_write(udc, DC_EPTYPE, DC_EPENABLE | type); + + spin_unlock_irqrestore(&udc->lock, flags); + + return 0; +} + +static int isp1760_ep_disable(struct usb_ep *ep) +{ + struct isp1760_ep *uep = ep_to_udc_ep(ep); + struct isp1760_udc *udc = uep->udc; + struct isp1760_request *req, *nreq; + LIST_HEAD(req_list); + unsigned long flags; + + dev_dbg(udc->isp->dev, "%s\n", __func__); + + spin_lock_irqsave(&udc->lock, flags); + + if (!uep->desc) { + dev_dbg(udc->isp->dev, "%s: endpoint not enabled\n", __func__); + spin_unlock_irqrestore(&udc->lock, flags); + return -EINVAL; + } + + uep->desc = NULL; + uep->maxpacket = 0; + + isp1760_udc_select_ep(uep); + isp1760_udc_write(udc, DC_EPTYPE, 0); + + /* TODO Synchronize with the IRQ handler */ + + list_splice_init(&uep->queue, &req_list); + + spin_unlock_irqrestore(&udc->lock, flags); + + list_for_each_entry_safe(req, nreq, &req_list, queue) { + list_del(&req->queue); + isp1760_udc_request_complete(uep, req, -ESHUTDOWN); + } + + return 0; +} + +static struct usb_request *isp1760_ep_alloc_request(struct usb_ep *ep, + gfp_t gfp_flags) +{ + struct isp1760_request *req; + + req = kzalloc(sizeof(*req), gfp_flags); + + return &req->req; +} + +static void isp1760_ep_free_request(struct usb_ep *ep, struct usb_request *_req) +{ + struct isp1760_request *req = req_to_udc_req(_req); + + kfree(req); +} + +static int isp1760_ep_queue(struct usb_ep *ep, struct usb_request *_req, + gfp_t gfp_flags) +{ + struct isp1760_request *req = req_to_udc_req(_req); + struct isp1760_ep *uep = ep_to_udc_ep(ep); + struct isp1760_udc *udc = uep->udc; + bool complete = false; + unsigned long flags; + int ret = 0; + + _req->status = -EINPROGRESS; + _req->actual = 0; + + spin_lock_irqsave(&udc->lock, flags); + + dev_dbg(udc->isp->dev, + "%s: req %p (%u bytes%s) ep %p(0x%02x)\n", __func__, _req, + _req->length, _req->zero ? " (zlp)" : "", uep, uep->addr); + + req->ep = uep; + + if (uep->addr == 0) { + if (_req->length != udc->ep0_length && + udc->ep0_state != ISP1760_CTRL_DATA_IN) { + dev_dbg(udc->isp->dev, + "%s: invalid length %u for req %p\n", + __func__, _req->length, req); + ret = -EINVAL; + goto done; + } + + switch (udc->ep0_state) { + case ISP1760_CTRL_DATA_IN: + dev_dbg(udc->isp->dev, "%s: transmitting req %p\n", + __func__, req); + + list_add_tail(&req->queue, &uep->queue); + isp1760_udc_transmit(uep, req); + break; + + case ISP1760_CTRL_DATA_OUT: + list_add_tail(&req->queue, &uep->queue); + __isp1760_udc_select_ep(uep, USB_DIR_OUT); + isp1760_udc_write(udc, DC_CTRLFUNC, DC_DSEN); + break; + + case ISP1760_CTRL_STATUS: + complete = true; + break; + + default: + dev_dbg(udc->isp->dev, "%s: invalid ep0 state\n", + __func__); + ret = -EINVAL; + break; + } + } else if (uep->desc) { + bool empty = list_empty(&uep->queue); + + list_add_tail(&req->queue, &uep->queue); + if ((uep->addr & USB_DIR_IN) && !uep->halted && empty) + isp1760_udc_transmit(uep, req); + else if (!(uep->addr & USB_DIR_IN) && uep->rx_pending) + complete = isp1760_udc_receive(uep, req); + } else { + dev_dbg(udc->isp->dev, + "%s: can't queue request to disabled ep%02x\n", + __func__, uep->addr); + ret = -ESHUTDOWN; + } + +done: + if (ret < 0) + req->ep = NULL; + + spin_unlock_irqrestore(&udc->lock, flags); + + if (complete) + isp1760_udc_request_complete(uep, req, 0); + + return ret; +} + +static int isp1760_ep_dequeue(struct usb_ep *ep, struct usb_request *_req) +{ + struct isp1760_request *req = req_to_udc_req(_req); + struct isp1760_ep *uep = ep_to_udc_ep(ep); + struct isp1760_udc *udc = uep->udc; + unsigned long flags; + + dev_dbg(uep->udc->isp->dev, "%s(ep%02x)\n", __func__, uep->addr); + + spin_lock_irqsave(&udc->lock, flags); + + if (req->ep != uep) + req = NULL; + else + list_del(&req->queue); + + spin_unlock_irqrestore(&udc->lock, flags); + + if (!req) + return -EINVAL; + + isp1760_udc_request_complete(uep, req, -ECONNRESET); + return 0; +} + +static int __isp1760_ep_set_halt(struct isp1760_ep *uep, bool stall, bool wedge) +{ + struct isp1760_udc *udc = uep->udc; + int ret; + + if (!uep->addr) { + /* + * Halting the control endpoint is only valid as a delayed error + * response to a SETUP packet. Make sure EP0 is in the right + * stage and that the gadget isn't trying to clear the halt + * condition. + */ + if (WARN_ON(udc->ep0_state == ISP1760_CTRL_SETUP || !stall || + wedge)) { + return -EINVAL; + } + } + + if (uep->addr && !uep->desc) { + dev_dbg(udc->isp->dev, "%s: ep%02x is disabled\n", __func__, + uep->addr); + return -EINVAL; + } + + if (uep->addr & USB_DIR_IN) { + /* Refuse to halt IN endpoints with active transfers. */ + if (!list_empty(&uep->queue)) { + dev_dbg(udc->isp->dev, + "%s: ep%02x has request pending\n", __func__, + uep->addr); + return -EAGAIN; + } + } + + ret = __isp1760_udc_set_halt(uep, stall); + if (ret < 0) + return ret; + + if (!uep->addr) { + /* + * Stalling EP0 completes the control transaction, move back to + * the SETUP state. + */ + udc->ep0_state = ISP1760_CTRL_SETUP; + return 0; + } + + if (wedge) + uep->wedged = true; + else if (!stall) + uep->wedged = false; + + return 0; +} + +static int isp1760_ep_set_halt(struct usb_ep *ep, int value) +{ + struct isp1760_ep *uep = ep_to_udc_ep(ep); + unsigned long flags; + int ret; + + dev_dbg(uep->udc->isp->dev, "%s: %s halt on ep%02x\n", __func__, + value ? "set" : "clear", uep->addr); + + spin_lock_irqsave(&uep->udc->lock, flags); + ret = __isp1760_ep_set_halt(uep, value, false); + spin_unlock_irqrestore(&uep->udc->lock, flags); + + return ret; +} + +static int isp1760_ep_set_wedge(struct usb_ep *ep) +{ + struct isp1760_ep *uep = ep_to_udc_ep(ep); + unsigned long flags; + int ret; + + dev_dbg(uep->udc->isp->dev, "%s: set wedge on ep%02x)\n", __func__, + uep->addr); + + spin_lock_irqsave(&uep->udc->lock, flags); + ret = __isp1760_ep_set_halt(uep, true, true); + spin_unlock_irqrestore(&uep->udc->lock, flags); + + return ret; +} + +static void isp1760_ep_fifo_flush(struct usb_ep *ep) +{ + struct isp1760_ep *uep = ep_to_udc_ep(ep); + struct isp1760_udc *udc = uep->udc; + unsigned long flags; + + spin_lock_irqsave(&udc->lock, flags); + + isp1760_udc_select_ep(uep); + + /* + * Set the CLBUF bit twice to flush both buffers in case double + * buffering is enabled. + */ + isp1760_udc_write(udc, DC_CTRLFUNC, DC_CLBUF); + isp1760_udc_write(udc, DC_CTRLFUNC, DC_CLBUF); + + spin_unlock_irqrestore(&udc->lock, flags); +} + +static const struct usb_ep_ops isp1760_ep_ops = { + .enable = isp1760_ep_enable, + .disable = isp1760_ep_disable, + .alloc_request = isp1760_ep_alloc_request, + .free_request = isp1760_ep_free_request, + .queue = isp1760_ep_queue, + .dequeue = isp1760_ep_dequeue, + .set_halt = isp1760_ep_set_halt, + .set_wedge = isp1760_ep_set_wedge, + .fifo_flush = isp1760_ep_fifo_flush, +}; + +/* ----------------------------------------------------------------------------- + * Device States + */ + +/* Called with the UDC spinlock held. */ +static void isp1760_udc_connect(struct isp1760_udc *udc) +{ + usb_gadget_set_state(&udc->gadget, USB_STATE_POWERED); + mod_timer(&udc->vbus_timer, jiffies + ISP1760_VBUS_POLL_INTERVAL); +} + +/* Called with the UDC spinlock held. */ +static void isp1760_udc_disconnect(struct isp1760_udc *udc) +{ + if (udc->gadget.state < USB_STATE_POWERED) + return; + + dev_dbg(udc->isp->dev, "Device disconnected in state %u\n", + udc->gadget.state); + + udc->gadget.speed = USB_SPEED_UNKNOWN; + usb_gadget_set_state(&udc->gadget, USB_STATE_ATTACHED); + + if (udc->driver->disconnect) + udc->driver->disconnect(&udc->gadget); + + del_timer(&udc->vbus_timer); + + /* TODO Reset all endpoints ? */ +} + +static void isp1760_udc_init_hw(struct isp1760_udc *udc) +{ + /* + * The device controller currently shares its interrupt with the host + * controller, the DC_IRQ polarity and signaling mode are ignored. Set + * the to active-low level-triggered. + * + * Configure the control, in and out pipes to generate interrupts on + * ACK tokens only (and NYET for the out pipe). The default + * configuration also generates an interrupt on the first NACK token. + */ + isp1760_udc_write(udc, DC_INTCONF, DC_CDBGMOD_ACK | DC_DDBGMODIN_ACK | + DC_DDBGMODOUT_ACK_NYET); + + isp1760_udc_write(udc, DC_INTENABLE, DC_IEPRXTX(7) | DC_IEPRXTX(6) | + DC_IEPRXTX(5) | DC_IEPRXTX(4) | DC_IEPRXTX(3) | + DC_IEPRXTX(2) | DC_IEPRXTX(1) | DC_IEPRXTX(0) | + DC_IEP0SETUP | DC_IEVBUS | DC_IERESM | DC_IESUSP | + DC_IEHS_STA | DC_IEBRST); + + if (udc->connected) + isp1760_set_pullup(udc->isp, true); + + isp1760_udc_write(udc, DC_ADDRESS, DC_DEVEN); +} + +static void isp1760_udc_reset(struct isp1760_udc *udc) +{ + unsigned long flags; + + spin_lock_irqsave(&udc->lock, flags); + + /* + * The bus reset has reset most registers to their default value, + * reinitialize the UDC hardware. + */ + isp1760_udc_init_hw(udc); + + udc->ep0_state = ISP1760_CTRL_SETUP; + udc->gadget.speed = USB_SPEED_FULL; + + usb_gadget_udc_reset(&udc->gadget, udc->driver); + + spin_unlock_irqrestore(&udc->lock, flags); +} + +static void isp1760_udc_suspend(struct isp1760_udc *udc) +{ + if (udc->gadget.state < USB_STATE_DEFAULT) + return; + + if (udc->driver->suspend) + udc->driver->suspend(&udc->gadget); +} + +static void isp1760_udc_resume(struct isp1760_udc *udc) +{ + if (udc->gadget.state < USB_STATE_DEFAULT) + return; + + if (udc->driver->resume) + udc->driver->resume(&udc->gadget); +} + +/* ----------------------------------------------------------------------------- + * Gadget Operations + */ + +static int isp1760_udc_get_frame(struct usb_gadget *gadget) +{ + struct isp1760_udc *udc = gadget_to_udc(gadget); + + return isp1760_udc_read(udc, DC_FRAMENUM) & ((1 << 11) - 1); +} + +static int isp1760_udc_wakeup(struct usb_gadget *gadget) +{ + struct isp1760_udc *udc = gadget_to_udc(gadget); + + dev_dbg(udc->isp->dev, "%s\n", __func__); + return -ENOTSUPP; +} + +static int isp1760_udc_set_selfpowered(struct usb_gadget *gadget, + int is_selfpowered) +{ + struct isp1760_udc *udc = gadget_to_udc(gadget); + + if (is_selfpowered) + udc->devstatus |= 1 << USB_DEVICE_SELF_POWERED; + else + udc->devstatus &= ~(1 << USB_DEVICE_SELF_POWERED); + + return 0; +} + +static int isp1760_udc_pullup(struct usb_gadget *gadget, int is_on) +{ + struct isp1760_udc *udc = gadget_to_udc(gadget); + + isp1760_set_pullup(udc->isp, is_on); + udc->connected = is_on; + + return 0; +} + +static int isp1760_udc_start(struct usb_gadget *gadget, + struct usb_gadget_driver *driver) +{ + struct isp1760_udc *udc = gadget_to_udc(gadget); + + /* The hardware doesn't support low speed. */ + if (driver->max_speed < USB_SPEED_FULL) { + dev_err(udc->isp->dev, "Invalid gadget driver\n"); + return -EINVAL; + } + + spin_lock(&udc->lock); + + if (udc->driver) { + dev_err(udc->isp->dev, "UDC already has a gadget driver\n"); + spin_unlock(&udc->lock); + return -EBUSY; + } + + udc->driver = driver; + + spin_unlock(&udc->lock); + + dev_dbg(udc->isp->dev, "starting UDC with driver %s\n", + driver->function); + + udc->devstatus = 0; + udc->connected = true; + + usb_gadget_set_state(&udc->gadget, USB_STATE_ATTACHED); + + /* DMA isn't supported yet, don't enable the DMA clock. */ + isp1760_udc_write(udc, DC_MODE, DC_GLINTENA); + + isp1760_udc_init_hw(udc); + + dev_dbg(udc->isp->dev, "UDC started with driver %s\n", + driver->function); + + return 0; +} + +static int isp1760_udc_stop(struct usb_gadget *gadget) +{ + struct isp1760_udc *udc = gadget_to_udc(gadget); + + dev_dbg(udc->isp->dev, "%s\n", __func__); + + del_timer_sync(&udc->vbus_timer); + + isp1760_udc_write(udc, DC_MODE, 0); + + spin_lock(&udc->lock); + udc->driver = NULL; + spin_unlock(&udc->lock); + + return 0; +} + +static struct usb_gadget_ops isp1760_udc_ops = { + .get_frame = isp1760_udc_get_frame, + .wakeup = isp1760_udc_wakeup, + .set_selfpowered = isp1760_udc_set_selfpowered, + .pullup = isp1760_udc_pullup, + .udc_start = isp1760_udc_start, + .udc_stop = isp1760_udc_stop, +}; + +/* ----------------------------------------------------------------------------- + * Interrupt Handling + */ + +static irqreturn_t isp1760_udc_irq(int irq, void *dev) +{ + struct isp1760_udc *udc = dev; + unsigned int i; + u32 status; + + status = isp1760_udc_read(udc, DC_INTERRUPT) + & isp1760_udc_read(udc, DC_INTENABLE); + isp1760_udc_write(udc, DC_INTERRUPT, status); + + if (status & DC_IEVBUS) { + dev_dbg(udc->isp->dev, "%s(VBUS)\n", __func__); + /* The VBUS interrupt is only triggered when VBUS appears. */ + spin_lock(&udc->lock); + isp1760_udc_connect(udc); + spin_unlock(&udc->lock); + } + + if (status & DC_IEBRST) { + dev_dbg(udc->isp->dev, "%s(BRST)\n", __func__); + + isp1760_udc_reset(udc); + } + + for (i = 0; i <= 7; ++i) { + struct isp1760_ep *ep = &udc->ep[i*2]; + + if (status & DC_IEPTX(i)) { + dev_dbg(udc->isp->dev, "%s(EPTX%u)\n", __func__, i); + isp1760_ep_tx_complete(ep); + } + + if (status & DC_IEPRX(i)) { + dev_dbg(udc->isp->dev, "%s(EPRX%u)\n", __func__, i); + isp1760_ep_rx_ready(i ? ep - 1 : ep); + } + } + + if (status & DC_IEP0SETUP) { + dev_dbg(udc->isp->dev, "%s(EP0SETUP)\n", __func__); + + isp1760_ep0_setup(udc); + } + + if (status & DC_IERESM) { + dev_dbg(udc->isp->dev, "%s(RESM)\n", __func__); + isp1760_udc_resume(udc); + } + + if (status & DC_IESUSP) { + dev_dbg(udc->isp->dev, "%s(SUSP)\n", __func__); + + spin_lock(&udc->lock); + if (!(isp1760_udc_read(udc, DC_MODE) & DC_VBUSSTAT)) + isp1760_udc_disconnect(udc); + else + isp1760_udc_suspend(udc); + spin_unlock(&udc->lock); + } + + if (status & DC_IEHS_STA) { + dev_dbg(udc->isp->dev, "%s(HS_STA)\n", __func__); + udc->gadget.speed = USB_SPEED_HIGH; + } + + return status ? IRQ_HANDLED : IRQ_NONE; +} + +static void isp1760_udc_vbus_poll(unsigned long data) +{ + struct isp1760_udc *udc = (struct isp1760_udc *)data; + unsigned long flags; + + spin_lock_irqsave(&udc->lock, flags); + + if (!(isp1760_udc_read(udc, DC_MODE) & DC_VBUSSTAT)) + isp1760_udc_disconnect(udc); + else if (udc->gadget.state >= USB_STATE_POWERED) + mod_timer(&udc->vbus_timer, + jiffies + ISP1760_VBUS_POLL_INTERVAL); + + spin_unlock_irqrestore(&udc->lock, flags); +} + +/* ----------------------------------------------------------------------------- + * Registration + */ + +static void isp1760_udc_init_eps(struct isp1760_udc *udc) +{ + unsigned int i; + + INIT_LIST_HEAD(&udc->gadget.ep_list); + + for (i = 0; i < ARRAY_SIZE(udc->ep); ++i) { + struct isp1760_ep *ep = &udc->ep[i]; + unsigned int ep_num = (i + 1) / 2; + bool is_in = !(i & 1); + + ep->udc = udc; + + INIT_LIST_HEAD(&ep->queue); + + ep->addr = (ep_num && is_in ? USB_DIR_IN : USB_DIR_OUT) + | ep_num; + ep->desc = NULL; + + sprintf(ep->name, "ep%u%s", ep_num, + ep_num ? (is_in ? "in" : "out") : ""); + + ep->ep.ops = &isp1760_ep_ops; + ep->ep.name = ep->name; + + /* + * Hardcode the maximum packet sizes for now, to 64 bytes for + * the control endpoint and 512 bytes for all other endpoints. + * This fits in the 8kB FIFO without double-buffering. + */ + if (ep_num == 0) { + ep->ep.maxpacket = 64; + ep->maxpacket = 64; + udc->gadget.ep0 = &ep->ep; + } else { + ep->ep.maxpacket = 512; + ep->maxpacket = 0; + list_add_tail(&ep->ep.ep_list, &udc->gadget.ep_list); + } + } +} + +static int isp1760_udc_init(struct isp1760_udc *udc) +{ + u16 scratch; + u32 chipid; + + /* + * Check that the controller is present by writing to the scratch + * register, modifying the bus pattern by reading from the chip ID + * register, and reading the scratch register value back. The chip ID + * and scratch register contents must match the expected values. + */ + isp1760_udc_write(udc, DC_SCRATCH, 0xbabe); + chipid = isp1760_udc_read(udc, DC_CHIPID); + scratch = isp1760_udc_read(udc, DC_SCRATCH); + + if (scratch != 0xbabe) { + dev_err(udc->isp->dev, + "udc: scratch test failed (0x%04x/0x%08x)\n", + scratch, chipid); + return -ENODEV; + } + + if (chipid != 0x00011582) { + dev_err(udc->isp->dev, "udc: invalid chip ID 0x%08x\n", chipid); + return -ENODEV; + } + + /* Reset the device controller. */ + isp1760_udc_write(udc, DC_MODE, DC_SFRESET); + usleep_range(10000, 11000); + isp1760_udc_write(udc, DC_MODE, 0); + usleep_range(10000, 11000); + + return 0; +} + +int isp1760_udc_register(struct isp1760_device *isp, int irq, + unsigned long irqflags) +{ + struct isp1760_udc *udc = &isp->udc; + const char *devname; + int ret; + + udc->irq = -1; + udc->isp = isp; + udc->regs = isp->regs; + + spin_lock_init(&udc->lock); + setup_timer(&udc->vbus_timer, isp1760_udc_vbus_poll, + (unsigned long)udc); + + ret = isp1760_udc_init(udc); + if (ret < 0) + return ret; + + devname = dev_name(isp->dev); + udc->irqname = kmalloc(strlen(devname) + 7, GFP_KERNEL); + if (!udc->irqname) + return -ENOMEM; + + sprintf(udc->irqname, "%s (udc)", devname); + + ret = request_irq(irq, isp1760_udc_irq, IRQF_SHARED | IRQF_DISABLED | + irqflags, udc->irqname, udc); + if (ret < 0) + goto error; + + udc->irq = irq; + + /* + * Initialize the gadget static fields and register its device. Gadget + * fields that vary during the life time of the gadget are initialized + * by the UDC core. + */ + udc->gadget.ops = &isp1760_udc_ops; + udc->gadget.speed = USB_SPEED_UNKNOWN; + udc->gadget.max_speed = USB_SPEED_HIGH; + udc->gadget.name = "isp1761_udc"; + + isp1760_udc_init_eps(udc); + + ret = usb_add_gadget_udc(isp->dev, &udc->gadget); + if (ret < 0) + goto error; + + return 0; + +error: + if (udc->irq >= 0) + free_irq(udc->irq, udc); + kfree(udc->irqname); + + return ret; +} + +void isp1760_udc_unregister(struct isp1760_device *isp) +{ + struct isp1760_udc *udc = &isp->udc; + + if (!udc->isp) + return; + + usb_del_gadget_udc(&udc->gadget); + + free_irq(udc->irq, udc); + kfree(udc->irqname); +} |