[RFC PATCH v1 06/14] usb:cdns3: Initialization code for Device side

From: Pawel Laszczak
Date: Sat Nov 03 2018 - 13:53:12 EST

Patch implements a set of functions responsible for initialization,
configuration, starting and stopping device mode.
This patch also adds new ep0.c that holds all functions related
to endpoint 0.

Signed-off-by: Pawel Laszczak <pawell@xxxxxxxxxxx>
---
drivers/usb/cdns3/Makefile | 2 +-
drivers/usb/cdns3/ep0.c | 105 +++++++++++
drivers/usb/cdns3/gadget.c | 361 ++++++++++++++++++++++++++++++++++++-
drivers/usb/cdns3/gadget.h | 4 +
4 files changed, 468 insertions(+), 4 deletions(-)
create mode 100644 drivers/usb/cdns3/ep0.c

diff --git a/drivers/usb/cdns3/Makefile b/drivers/usb/cdns3/Makefile
index d4ccfb49d844..f4cfc978626f 100644
--- a/drivers/usb/cdns3/Makefile
+++ b/drivers/usb/cdns3/Makefile
@@ -2,6 +2,6 @@ obj-$(CONFIG_USB_CDNS3) += cdns3.o
obj-$(CONFIG_USB_CDNS3_PCI_WRAP) += cdns3-pci.o

cdns3-y := core.o drd.o
-cdns3-$(CONFIG_USB_CDNS3_GADGET) += gadget.o
+cdns3-$(CONFIG_USB_CDNS3_GADGET) += gadget.o ep0.o
cdns3-$(CONFIG_USB_CDNS3_HOST) += host.o
cdns3-pci-y := cdns3-pci-wrap.o
diff --git a/drivers/usb/cdns3/ep0.c b/drivers/usb/cdns3/ep0.c
new file mode 100644
index 000000000000..c08d02665f9d
--- /dev/null
+++ b/drivers/usb/cdns3/ep0.c
@@ -0,0 +1,105 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Cadence USBSS DRD Driver - gadget side.
+ *
+ * Copyright (C) 2018 Cadence Design Systems.
+ * Copyright (C) 2017 NXP
+ *
+ * Authors: Pawel Jez <pjez@xxxxxxxxxxx>,
+ * Pawel Laszczak <pawell@xxxxxxxxxxx>
+ * Peter Chen <peter.chen@xxxxxxx>
+ */
+
+#include "gadget.h"
+
+static struct usb_endpoint_descriptor cdns3_gadget_ep0_desc = {
+ .bLength = USB_DT_ENDPOINT_SIZE,
+ .bDescriptorType = USB_DT_ENDPOINT,
+ .bmAttributes = USB_ENDPOINT_XFER_CONTROL,
+};
+
+static void cdns3_prepare_setup_packet(struct cdns3_device *priv_dev)
+{
+ //TODO: Implements this function
+}
+
+/**
+ * cdns3_ep0_config - Configures default endpoint
+ * @priv_dev: extended gadget object
+ *
+ * Functions sets parameters: maximal packet size and enables interrupts
+ */
+void cdns3_ep0_config(struct cdns3_device *priv_dev)
+{
+ struct cdns3_usb_regs __iomem *regs;
+ u32 max_packet_size = 64;
+
+ regs = priv_dev->regs;
+
+ if (priv_dev->gadget.speed == USB_SPEED_SUPER)
+ max_packet_size = 512;
+
+ if (priv_dev->ep0_request) {
+ list_del_init(&priv_dev->ep0_request->list);
+ priv_dev->ep0_request = NULL;
+ }
+
+ priv_dev->gadget.ep0->maxpacket = max_packet_size;
+ cdns3_gadget_ep0_desc.wMaxPacketSize = cpu_to_le16(max_packet_size);
+
+ /* init ep out */
+ cdns3_select_ep(priv_dev, USB_DIR_OUT);
+
+ writel(EP_CFG_ENABLE | EP_CFG_MAXPKTSIZE(max_packet_size),
+ &regs->ep_cfg);
+
+ writel(EP_STS_EN_SETUPEN | EP_STS_EN_DESCMISEN | EP_STS_EN_TRBERREN,
+ &regs->ep_sts_en);
+
+ /* init ep in */
+ cdns3_select_ep(priv_dev, USB_DIR_IN);
+
+ writel(EP_CFG_ENABLE | EP_CFG_MAXPKTSIZE(max_packet_size),
+ &regs->ep_cfg);
+
+ writel(EP_STS_EN_SETUPEN | EP_STS_EN_TRBERREN, &regs->ep_sts_en);
+
+ cdns3_set_register_bit(&regs->usb_conf, USB_CONF_U1DS | USB_CONF_U2DS);
+ cdns3_prepare_setup_packet(priv_dev);
+}
+
+/**
+ * cdns3_init_ep0 Initializes software endpoint 0 of gadget
+ * @cdns3: extended gadget object
+ *
+ * Returns 0 on success, error code elsewhere
+ */
+int cdns3_init_ep0(struct cdns3_device *priv_dev)
+{
+ struct cdns3_endpoint *ep0;
+
+ ep0 = devm_kzalloc(&priv_dev->dev, sizeof(struct cdns3_endpoint),
+ GFP_KERNEL);
+
+ if (!ep0)
+ return -ENOMEM;
+
+ ep0->cdns3_dev = priv_dev;
+ sprintf(ep0->name, "ep0");
+
+ /* fill linux fields */
+ //TODO: implements cdns3_gadget_ep0_ops object
+ //ep0->endpoint.ops = &cdns3_gadget_ep0_ops;
+ ep0->endpoint.maxburst = 1;
+ usb_ep_set_maxpacket_limit(&ep0->endpoint, ENDPOINT0_MAX_PACKET_LIMIT);
+ ep0->endpoint.address = 0;
+ ep0->endpoint.caps.type_control = 1;
+ ep0->endpoint.caps.dir_in = 1;
+ ep0->endpoint.caps.dir_out = 1;
+ ep0->endpoint.name = ep0->name;
+ ep0->endpoint.desc = &cdns3_gadget_ep0_desc;
+ priv_dev->gadget.ep0 = &ep0->endpoint;
+ INIT_LIST_HEAD(&ep0->request_list);
+
+ return 0;
+}
diff --git a/drivers/usb/cdns3/gadget.c b/drivers/usb/cdns3/gadget.c
index 41ce696719d7..e7975b00b21a 100644
--- a/drivers/usb/cdns3/gadget.c
+++ b/drivers/usb/cdns3/gadget.c
@@ -10,7 +10,261 @@
* Peter Chen <peter.chen@xxxxxxx>
*/

+#include <linux/dma-mapping.h>
+#include <linux/usb/gadget.h>
+
#include "core.h"
+#include "gadget-export.h"
+#include "gadget.h"
+
+/**
+ * cdns3_set_register_bit - set bit in given register.
+ * @ptr: address of device controller register to be read and changed
+ * @mask: bits requested to set
+ */
+void cdns3_set_register_bit(void __iomem *ptr, u32 mask)
+{
+ mask = readl(ptr) | mask;
+ writel(mask, ptr);
+}
+
+/**
+ * select_ep - selects endpoint
+ * @priv_dev: extended gadget object
+ * @ep: endpoint address
+ */
+void cdns3_select_ep(struct cdns3_device *priv_dev, u32 ep)
+{
+ if (priv_dev->selected_ep == ep)
+ return;
+
+ dev_dbg(&priv_dev->dev, "Ep sel: 0x%02x\n", ep);
+ priv_dev->selected_ep = ep;
+ writel(ep, &priv_dev->regs->ep_sel);
+ /* memory barrier for selecting endpoint. */
+ wmb();
+}
+
+/**
+ * cdns3_irq_handler - irq line interrupt handler
+ * @cdns: cdns3 instance
+ *
+ * Returns IRQ_HANDLED when interrupt raised by USBSS_DEV,
+ * IRQ_NONE when interrupt raised by other device connected
+ * to the irq line
+ */
+static irqreturn_t cdns3_irq_handler_thread(struct cdns3 *cdns)
+{
+ irqreturn_t ret = IRQ_NONE;
+ //TODO: implements this function
+ return ret;
+}
+
+static void cdns3_gadget_config(struct cdns3_device *priv_dev)
+{
+ struct cdns3_usb_regs __iomem *regs = priv_dev->regs;
+
+ cdns3_ep0_config(priv_dev);
+
+ /* enable interrupts for endpoint 0 (in and out) */
+ writel(EP_IEN_EP_OUT0 | EP_IEN_EP_IN0, &regs->ep_ien);
+
+ /* enable generic interrupt*/
+ writel(USB_IEN_INIT, &regs->usb_ien);
+ writel(USB_CONF_CLK2OFFDS | USB_CONF_L1DS, &regs->usb_conf);
+ writel(USB_CONF_U1DS | USB_CONF_U2DS, &regs->usb_conf);
+ writel(USB_CONF_DMULT, &regs->usb_conf);
+ writel(USB_CONF_DEVEN, &regs->usb_conf);
+}
+
+/**
+ * cdns3_init_ep Initializes software endpoints of gadget
+ * @cdns3: extended gadget object
+ *
+ * Returns 0 on success, error code elsewhere
+ */
+static int cdns3_init_ep(struct cdns3_device *priv_dev)
+{
+ u32 ep_enabled_reg, iso_ep_reg;
+ struct cdns3_endpoint *priv_ep;
+ int found_endpoints = 0;
+ int ep_dir, ep_number;
+ u32 ep_mask;
+ int i;
+
+ /* Read it from USB_CAP3 to USB_CAP5 */
+ ep_enabled_reg = readl(&priv_dev->regs->usb_cap3);
+ iso_ep_reg = readl(&priv_dev->regs->usb_cap4);
+
+ dev_dbg(&priv_dev->dev, "Initializing non-zero endpoints\n");
+
+ for (i = 0; i < USB_SS_ENDPOINTS_MAX_COUNT; i++) {
+ ep_number = (i / 2) + 1;
+ ep_dir = i % 2;
+ ep_mask = BIT((16 * ep_dir) + ep_number);
+
+ if (!(ep_enabled_reg & ep_mask))
+ continue;
+
+ priv_ep = devm_kzalloc(&priv_dev->dev, sizeof(*priv_ep),
+ GFP_KERNEL);
+ if (!priv_ep)
+ return -ENOMEM;
+
+ /* set parent of endpoint object */
+ priv_ep->cdns3_dev = priv_dev;
+ priv_dev->eps[found_endpoints++] = priv_ep;
+
+ snprintf(priv_ep->name, sizeof(priv_ep->name), "ep%d%s",
+ ep_number, !!ep_dir ? "in" : "out");
+ priv_ep->endpoint.name = priv_ep->name;
+
+ usb_ep_set_maxpacket_limit(&priv_ep->endpoint,
+ ENDPOINT_MAX_PACKET_LIMIT);
+ priv_ep->endpoint.max_streams = ENDPOINT_MAX_STREAMS;
+ //TODO: Add implementation of cdns3_gadget_ep_ops
+ //priv_ep->endpoint.ops = &cdns3_gadget_ep_ops;
+ if (ep_dir)
+ priv_ep->endpoint.caps.dir_in = 1;
+ else
+ priv_ep->endpoint.caps.dir_out = 1;
+
+ if (iso_ep_reg & ep_mask)
+ priv_ep->endpoint.caps.type_iso = 1;
+
+ priv_ep->endpoint.caps.type_bulk = 1;
+ priv_ep->endpoint.caps.type_int = 1;
+ priv_ep->endpoint.maxburst = CDNS3_EP_BUF_SIZE - 1;
+
+ dev_info(&priv_dev->dev, "Initialized %s support: %s %s\n",
+ priv_ep->name,
+ priv_ep->endpoint.caps.type_bulk ? "BULK, INT" : "",
+ priv_ep->endpoint.caps.type_iso ? "ISO" : "");
+
+ list_add_tail(&priv_ep->endpoint.ep_list,
+ &priv_dev->gadget.ep_list);
+ INIT_LIST_HEAD(&priv_ep->request_list);
+ INIT_LIST_HEAD(&priv_ep->ep_match_pending_list);
+ }
+
+ priv_dev->ep_nums = found_endpoints;
+ return 0;
+}
+
+static void cdns3_gadget_release(struct device *dev)
+{
+ struct cdns3_device *priv_dev;
+
+ priv_dev = container_of(dev, struct cdns3_device, dev);
+ kfree(priv_dev);
+}
+
+static int __cdns3_gadget_init(struct cdns3 *cdns)
+{
+ struct cdns3_device *priv_dev;
+ struct device *dev;
+ int ret;
+
+ priv_dev = kzalloc(sizeof(*priv_dev), GFP_KERNEL);
+ if (!priv_dev)
+ return -ENOMEM;
+
+ dev = &priv_dev->dev;
+ dev->release = cdns3_gadget_release;
+ dev->parent = cdns->dev;
+ dev_set_name(dev, "gadget-cdns3");
+ cdns->gadget_dev = dev;
+
+ priv_dev->sysdev = cdns->dev;
+ ret = device_register(dev);
+ if (ret)
+ goto err1;
+
+ priv_dev->regs = cdns->dev_regs;
+
+ /* fill gadget fields */
+ priv_dev->gadget.max_speed = USB_SPEED_SUPER;
+ priv_dev->gadget.speed = USB_SPEED_UNKNOWN;
+ //TODO: Add implementation of cdns3_gadget_ops
+ //priv_dev->gadget.ops = &cdns3_gadget_ops;
+ priv_dev->gadget.name = "usb-ss-gadget";
+ priv_dev->gadget.sg_supported = 1;
+ priv_dev->is_connected = 0;
+
+ spin_lock_init(&priv_dev->lock);
+
+ priv_dev->in_standby_mode = 1;
+
+ /* initialize endpoint container */
+ INIT_LIST_HEAD(&priv_dev->gadget.ep_list);
+ INIT_LIST_HEAD(&priv_dev->ep_match_list);
+
+ ret = cdns3_init_ep0(priv_dev);
+ if (ret) {
+ dev_err(dev, "Failed to create endpoint 0\n");
+ ret = -ENOMEM;
+ goto err2;
+ }
+
+ ret = cdns3_init_ep(priv_dev);
+ if (ret) {
+ dev_err(dev, "Failed to create non zero endpoints\n");
+ ret = -ENOMEM;
+ goto err2;
+ }
+
+ /* allocate memory for default endpoint TRB */
+ priv_dev->trb_ep0 = dma_alloc_coherent(priv_dev->sysdev, 24,
+ &priv_dev->trb_ep0_dma, GFP_DMA);
+ if (!priv_dev->trb_ep0) {
+ dev_err(dev, "Failed to allocate memory for ep0 TRB\n");
+ ret = -ENOMEM;
+ goto err2;
+ }
+
+ /* allocate memory for setup packet buffer */
+ priv_dev->setup = dma_alloc_coherent(priv_dev->sysdev, 8,
+ &priv_dev->setup_dma, GFP_DMA);
+ if (!priv_dev->setup) {
+ dev_err(dev, "Failed to allocate memory for SETUP buffer\n");
+ ret = -ENOMEM;
+ goto err3;
+ }
+
+ dev_dbg(dev, "Device Controller version: %08x\n",
+ readl(&priv_dev->regs->usb_cap6));
+ dev_dbg(dev, "USB Capabilities:: %08x\n",
+ readl(&priv_dev->regs->usb_cap1));
+ dev_dbg(dev, "On-Chip memory cnfiguration: %08x\n",
+ readl(&priv_dev->regs->usb_cap2));
+
+ /* add USB gadget device */
+ ret = usb_add_gadget_udc(&priv_dev->dev, &priv_dev->gadget);
+ if (ret < 0) {
+ dev_err(dev, "Failed to register USB device controller\n");
+ goto err4;
+ }
+
+ priv_dev->zlp_buf = kzalloc(ENDPOINT_ZLP_BUF_SIZE, GFP_KERNEL);
+ if (!priv_dev->zlp_buf) {
+ ret = -ENOMEM;
+ goto err4;
+ }
+
+ return 0;
+err4:
+ dma_free_coherent(priv_dev->sysdev, 8, priv_dev->setup,
+ priv_dev->setup_dma);
+err3:
+ dma_free_coherent(priv_dev->sysdev, 20, priv_dev->trb_ep0,
+ priv_dev->trb_ep0_dma);
+err2:
+ device_del(dev);
+err1:
+ put_device(dev);
+ cdns->gadget_dev = NULL;
+ return ret;
+}

/**
* cdns3_gadget_remove: parent must call this to remove UDC
@@ -19,7 +273,96 @@
*/
void cdns3_gadget_remove(struct cdns3 *cdns)
{
- //TODO: implements this function
+ struct cdns3_device *priv_dev;
+
+ if (!cdns->roles[CDNS3_ROLE_GADGET])
+ return;
+
+ priv_dev = container_of(cdns->gadget_dev, struct cdns3_device, dev);
+ usb_del_gadget_udc(&priv_dev->gadget);
+ dma_free_coherent(priv_dev->sysdev, 8, priv_dev->setup,
+ priv_dev->setup_dma);
+ dma_free_coherent(priv_dev->sysdev, 20, priv_dev->trb_ep0,
+ priv_dev->trb_ep0_dma);
+ device_unregister(cdns->gadget_dev);
+ cdns->gadget_dev = NULL;
+ kfree(priv_dev->zlp_buf);
+}
+
+static int cdns3_gadget_start(struct cdns3 *cdns)
+{
+ struct cdns3_device *priv_dev = container_of(cdns->gadget_dev,
+ struct cdns3_device, dev);
+ unsigned long flags;
+
+ pm_runtime_get_sync(cdns->dev);
+ spin_lock_irqsave(&priv_dev->lock, flags);
+ priv_dev->start_gadget = 1;
+
+ if (!priv_dev->gadget_driver) {
+ spin_unlock_irqrestore(&priv_dev->lock, flags);
+ return 0;
+ }
+
+ cdns3_gadget_config(priv_dev);
+ priv_dev->in_standby_mode = 0;
+ spin_unlock_irqrestore(&priv_dev->lock, flags);
+ return 0;
+}
+
+static void __cdns3_gadget_stop(struct cdns3 *cdns)
+{
+ struct cdns3_device *priv_dev;
+ unsigned long flags;
+
+ priv_dev = container_of(cdns->gadget_dev, struct cdns3_device, dev);
+
+ if (priv_dev->gadget_driver)
+ priv_dev->gadget_driver->disconnect(&priv_dev->gadget);
+
+ usb_gadget_disconnect(&priv_dev->gadget);
+ spin_lock_irqsave(&priv_dev->lock, flags);
+ priv_dev->gadget.speed = USB_SPEED_UNKNOWN;
+
+ /* disable interrupt for device */
+ writel(0, &priv_dev->regs->usb_ien);
+ writel(USB_CONF_DEVDS, &priv_dev->regs->usb_conf);
+ priv_dev->start_gadget = 0;
+ spin_unlock_irqrestore(&priv_dev->lock, flags);
+}
+
+static void cdns3_gadget_stop(struct cdns3 *cdns)
+{
+ if (cdns->role == CDNS3_ROLE_GADGET)
+ __cdns3_gadget_stop(cdns);
+
+ pm_runtime_mark_last_busy(cdns->dev);
+ pm_runtime_put_autosuspend(cdns->dev);
+}
+
+static int cdns3_gadget_suspend(struct cdns3 *cdns, bool do_wakeup)
+{
+ __cdns3_gadget_stop(cdns);
+ return 0;
+}
+
+static int cdns3_gadget_resume(struct cdns3 *cdns, bool hibernated)
+{
+ struct cdns3_device *priv_dev;
+ unsigned long flags;
+
+ priv_dev = container_of(cdns->gadget_dev, struct cdns3_device, dev);
+ spin_lock_irqsave(&priv_dev->lock, flags);
+ priv_dev->start_gadget = 1;
+ if (!priv_dev->gadget_driver) {
+ spin_unlock_irqrestore(&priv_dev->lock, flags);
+ return 0;
+ }
+
+ cdns3_gadget_config(priv_dev);
+ priv_dev->in_standby_mode = 0;
+ spin_unlock_irqrestore(&priv_dev->lock, flags);
+ return 0;
}

/**
@@ -31,6 +374,18 @@ void cdns3_gadget_remove(struct cdns3 *cdns)
*/
int cdns3_gadget_init(struct cdns3 *cdns)
{
- //TODO: implements this function
- return 0;
+ struct cdns3_role_driver *rdrv;
+
+ rdrv = devm_kzalloc(cdns->dev, sizeof(*rdrv), GFP_KERNEL);
+ if (!rdrv)
+ return -ENOMEM;
+
+ rdrv->start = cdns3_gadget_start;
+ rdrv->stop = cdns3_gadget_stop;
+ rdrv->suspend = cdns3_gadget_suspend;
+ rdrv->resume = cdns3_gadget_resume;
+ rdrv->irq = cdns3_irq_handler_thread;
+ rdrv->name = "gadget";
+ cdns->roles[CDNS3_ROLE_GADGET] = rdrv;
+ return __cdns3_gadget_init(cdns);
}
diff --git a/drivers/usb/cdns3/gadget.h b/drivers/usb/cdns3/gadget.h
index c4b07827aae7..b57e863017b0 100644
--- a/drivers/usb/cdns3/gadget.h
+++ b/drivers/usb/cdns3/gadget.h
@@ -1064,4 +1064,8 @@ struct cdns3_device {
struct usb_request *pending_status_request;
};

+void cdns3_set_register_bit(void __iomem *ptr, u32 mask);
+int cdns3_init_ep0(struct cdns3_device *priv_dev);
+void cdns3_ep0_config(struct cdns3_device *priv_dev);
+void cdns3_select_ep(struct cdns3_device *priv_dev, u32 ep);
#endif /* __LINUX_CDNS3_GADGET */
--
2.17.1