[RFC 1/1] Changes to support the driver for platform device registration

From: Raviteja Garimella
Date: Thu Jan 05 2017 - 03:46:35 EST

-- Add OF based platform device registration
-- Modify debug prints to be compatible with both pci and platform devices
-- Add members to 'struct udc' for extcon and phy support
-- Add checks to not process repeated calls to udc connect and
disconnect routines
-- Kconfig changes

Signed-off-by: Raviteja Garimella <raviteja.garimella@xxxxxxxxxxxx>
---
drivers/usb/gadget/udc/Kconfig | 6 +-
drivers/usb/gadget/udc/amd5536udc.c | 397 +++++++++++++++++++++++++++++++++---
drivers/usb/gadget/udc/amd5536udc.h | 17 +-
3 files changed, 387 insertions(+), 33 deletions(-)

diff --git a/drivers/usb/gadget/udc/Kconfig b/drivers/usb/gadget/udc/Kconfig
index 658b8da..7728fec 100644
--- a/drivers/usb/gadget/udc/Kconfig
+++ b/drivers/usb/gadget/udc/Kconfig
@@ -263,7 +263,7 @@ source "drivers/usb/gadget/udc/bdc/Kconfig"

config USB_AMD5536UDC
tristate "AMD5536 UDC"
- depends on PCI
+ depends on PCI || OF
help
The AMD5536 UDC is part of the AMD Geode CS5536, an x86 southbridge.
It is a USB Highspeed DMA capable USB device controller. Beside ep0
@@ -271,6 +271,10 @@ config USB_AMD5536UDC
The UDC port supports OTG operation, and may be used as a host port
if it's not being used to implement peripheral or OTG roles.

+ This UDC is based on Synopsis Designware core USB Device controller
+ IP. The driver also supports UDCs integrated to ARM based SoC's like
+ Broadcom's Northstar2 and Cygnus platforms.
+
Say "y" to link the driver statically, or "m" to build a
dynamically linked module called "amd5536udc" and force all
gadget drivers to also be dynamically linked.
diff --git a/drivers/usb/gadget/udc/amd5536udc.c b/drivers/usb/gadget/udc/amd5536udc.c
index ea03ca7..b086cf1 100644
--- a/drivers/usb/gadget/udc/amd5536udc.c
+++ b/drivers/usb/gadget/udc/amd5536udc.c
@@ -22,16 +22,25 @@
* UDC DMA requires 32-bit aligned buffers so DMA with gadget ether does not
* work without updating NET_IP_ALIGN. Or PIO mode (module param "use_dma=0")
* can be used with gadget ether.
+ *
+ * This driver is compatible for Broadcom's UDC for Northstar2 and Cygnus
+ * SOCs. The UDC is based on Synopsys designware core USB device controller IP.
*/

/* debug control */
/* #define UDC_VERBOSE */

/* Driver strings */
-#define UDC_MOD_DESCRIPTION "AMD 5536 UDC - USB Device Controller"
+#define UDC_MOD_DESCRIPTION "AMD 5536 UDC - Synopsys USB Device Controller"
#define UDC_DRIVER_VERSION_STRING "01.00.0206"

/* system */
+#include <linux/extcon.h>
+#include <linux/of_address.h>
+#include <linux/of_irq.h>
+#include <linux/of_gpio.h>
+#include <linux/platform_device.h>
+#include <linux/phy/phy.h>
#include <linux/module.h>
#include <linux/pci.h>
#include <linux/kernel.h>
@@ -251,18 +260,18 @@ static void print_regs(struct udc *dev)
if (use_dma && use_dma_ppb && !use_dma_ppb_du) {
DBG(dev, "DMA mode = PPBNDU (packet per buffer "
"WITHOUT desc. update)\n");
- dev_info(&dev->pdev->dev, "DMA mode (%s)\n", "PPBNDU");
+ dev_info(dev->dev, "DMA mode (%s)\n", "PPBNDU");
} else if (use_dma && use_dma_ppb && use_dma_ppb_du) {
DBG(dev, "DMA mode = PPBDU (packet per buffer "
"WITH desc. update)\n");
- dev_info(&dev->pdev->dev, "DMA mode (%s)\n", "PPBDU");
+ dev_info(dev->dev, "DMA mode (%s)\n", "PPBDU");
}
if (use_dma && use_dma_bufferfill_mode) {
DBG(dev, "DMA mode = BF (buffer fill mode)\n");
- dev_info(&dev->pdev->dev, "DMA mode (%s)\n", "BF");
+ dev_info(dev->dev, "DMA mode (%s)\n", "BF");
}
if (!use_dma)
- dev_info(&dev->pdev->dev, "FIFO mode\n");
+ dev_info(dev->dev, "FIFO mode\n");
DBG(dev, "-------------------------------------------------------\n");
}

@@ -1666,8 +1675,11 @@ static void udc_setup_endpoints(struct udc *dev)
/* Bringup after Connect event, initial bringup to be ready for ep0 events */
static void usb_connect(struct udc *dev)
{
+ /* Return if already connected */
+ if (dev->connected)
+ return;

- dev_info(&dev->pdev->dev, "USB Connect\n");
+ dev_info(dev->dev, "USB Connect\n");

dev->connected = 1;

@@ -1684,8 +1696,11 @@ static void usb_connect(struct udc *dev)
*/
static void usb_disconnect(struct udc *dev)
{
+ /* Return if already disconnected */
+ if (!dev->connected)
+ return;

- dev_info(&dev->pdev->dev, "USB Disconnect\n");
+ dev_info(dev->dev, "USB Disconnect\n");

dev->connected = 0;

@@ -1758,11 +1773,15 @@ static void udc_soft_reset(struct udc *dev)
/* device int. status reset */
writel(UDC_DEV_MSK_DISABLE, &dev->regs->irqsts);

- spin_lock_irqsave(&udc_irq_spinlock, flags);
- writel(AMD_BIT(UDC_DEVCFG_SOFTRESET), &dev->regs->cfg);
- readl(&dev->regs->cfg);
- spin_unlock_irqrestore(&udc_irq_spinlock, flags);
-
+ /* Don't do this for Broadcom UDC since this is a reserved
+ * bit.
+ */
+ if (dev->chiprev != UDC_BCM_REV) {
+ spin_lock_irqsave(&udc_irq_spinlock, flags);
+ writel(AMD_BIT(UDC_DEVCFG_SOFTRESET), &dev->regs->cfg);
+ readl(&dev->regs->cfg);
+ spin_unlock_irqrestore(&udc_irq_spinlock, flags);
+ }
}

/* RDE timer callback to set RDE bit */
@@ -2149,7 +2168,7 @@ static irqreturn_t udc_data_out_isr(struct udc *dev, int ep_ix)
}
/* HE event ? */
if (tmp & AMD_BIT(UDC_EPSTS_HE)) {
- dev_err(&dev->pdev->dev, "HE ep%dout occurred\n", ep->num);
+ dev_err(dev->dev, "HE ep%dout occurred\n", ep->num);

/* clear HE */
writel(tmp | AMD_BIT(UDC_EPSTS_HE), &ep->regs->sts);
@@ -2348,7 +2367,7 @@ static irqreturn_t udc_data_in_isr(struct udc *dev, int ep_ix)
if (use_dma) {
/* BNA ? */
if (epsts & AMD_BIT(UDC_EPSTS_BNA)) {
- dev_err(&dev->pdev->dev,
+ dev_err(dev->dev,
"BNA ep%din occurred - DESPTR = %08lx\n",
ep->num,
(unsigned long) readl(&ep->regs->desptr));
@@ -2361,7 +2380,7 @@ static irqreturn_t udc_data_in_isr(struct udc *dev, int ep_ix)
}
/* HE event ? */
if (epsts & AMD_BIT(UDC_EPSTS_HE)) {
- dev_err(&dev->pdev->dev,
+ dev_err(dev->dev,
"HE ep%dn occurred - DESPTR = %08lx\n",
ep->num, (unsigned long) readl(&ep->regs->desptr));

@@ -2999,7 +3018,7 @@ __acquires(dev->lock)

/* link up all endpoints */
udc_setup_endpoints(dev);
- dev_info(&dev->pdev->dev, "Connect: %s\n",
+ dev_info(dev->dev, "Connect: %s\n",
usb_speed_string(dev->gadget.speed));

/* init ep 0 */
@@ -3162,7 +3181,7 @@ static int init_dma_pools(struct udc *dev)
}

/* DMA setup */
- dev->data_requests = dma_pool_create("data_requests", NULL,
+ dev->data_requests = dma_pool_create("data_requests", dev->dev,
sizeof(struct udc_data_dma), 0, 0);
if (!dev->data_requests) {
DBG(dev, "can't get request data pool\n");
@@ -3173,7 +3192,7 @@ static int init_dma_pools(struct udc *dev)
dev->ep[UDC_EP0IN_IX].dma = &dev->regs->ctl;

/* dma desc for setup data */
- dev->stp_requests = dma_pool_create("setup requests", NULL,
+ dev->stp_requests = dma_pool_create("setup requests", dev->dev,
sizeof(struct udc_stp_dma), 0, 0);
if (!dev->stp_requests) {
DBG(dev, "can't get stp request pool\n");
@@ -3232,24 +3251,29 @@ static int udc_probe(struct udc *dev)
/* init registers, interrupts, ... */
startup_registers(dev);

- dev_info(&dev->pdev->dev, "%s\n", mod_desc);
+ dev_info(dev->dev, "%s\n", mod_desc);

snprintf(tmp, sizeof(tmp), "%d", dev->irq);
- dev_info(&dev->pdev->dev,
- "irq %s, pci mem %08lx, chip rev %02x(Geode5536 %s)\n",
- tmp, dev->phys_addr, dev->chiprev,
- (dev->chiprev == UDC_HSA0_REV) ? "A0" : "B1");
- strcpy(tmp, UDC_DRIVER_VERSION_STRING);
- if (dev->chiprev == UDC_HSA0_REV) {
- dev_err(&dev->pdev->dev, "chip revision is A0; too old\n");
- retval = -ENODEV;
- goto finished;
+
+ /* Print this device info for AMD chips only */
+ if (dev->chiprev == UDC_HSA0_REV ||
+ dev->chiprev == UDC_HSB1_REV) {
+ dev_info(dev->dev, "irq %s, pci mem %08lx, chip rev %02x(Geode5536 %s)\n",
+ tmp, dev->phys_addr, dev->chiprev,
+ (dev->chiprev == UDC_HSA0_REV) ?
+ "A0" : "B1");
+ strcpy(tmp, UDC_DRIVER_VERSION_STRING);
+ if (dev->chiprev == UDC_HSA0_REV) {
+ dev_err(dev->dev, "chip revision is A0; too old\n");
+ retval = -ENODEV;
+ goto finished;
+ }
+ dev_info(dev->dev,
+ "driver version: %s(for Geode5536 B1)\n", tmp);
}
- dev_info(&dev->pdev->dev,
- "driver version: %s(for Geode5536 B1)\n", tmp);
udc = dev;

- retval = usb_add_gadget_udc_release(&udc->pdev->dev, &dev->gadget,
+ retval = usb_add_gadget_udc_release(udc->dev, &dev->gadget,
gadget_release);
if (retval)
goto finished;
@@ -3363,6 +3387,7 @@ static int udc_pci_probe(
dev->phys_addr = resource;
dev->irq = pdev->irq;
dev->pdev = pdev;
+ dev->dev = &pdev->dev;

/* general probing */
if (udc_probe(dev)) {
@@ -3408,6 +3433,316 @@ static struct pci_driver udc_pci_driver = {

module_pci_driver(udc_pci_driver);

+void start_udc(struct udc *udc)
+{
+ if (udc->driver) {
+ dev_info(udc->dev, "Connecting...\n");
+ udc_enable_dev_setup_interrupts(udc);
+ udc_basic_init(udc);
+ udc->connected = 1;
+ }
+}
+
+void stop_udc(struct udc *udc)
+{
+ int num;
+ u32 reg;
+
+ spin_lock(&udc->lock);
+
+ /* Flush the receieve fifo */
+ reg = readl(&udc->regs->ctl);
+ reg |= AMD_BIT(UDC_DEVCTL_SRX_FLUSH);
+ writel(reg, &udc->regs->ctl);
+
+ reg = readl(&udc->regs->ctl);
+ reg &= ~(AMD_BIT(UDC_DEVCTL_SRX_FLUSH));
+ writel(reg, &udc->regs->ctl);
+ dev_dbg(udc->dev, "ep rx queue flushed\n");
+
+ /* Mask interrupts. Required more so when the
+ * UDC is connected to a DRD phy.
+ */
+ udc_mask_unused_interrupts(udc);
+
+ /* Disconnect gadget driver */
+ if (udc->driver) {
+ spin_unlock(&udc->lock);
+ udc->driver->disconnect(&udc->gadget);
+ spin_lock(&udc->lock);
+
+ /* empty queues */
+ for (num = 0; num < UDC_EP_NUM; num++)
+ empty_req_queue(&udc->ep[num]);
+ }
+ udc->connected = 0;
+
+ spin_unlock(&udc->lock);
+ dev_info(udc->dev, "Device disconnected\n");
+}
+
+void udc_drd_work(struct work_struct *work)
+{
+ struct udc *udc;
+
+ udc = container_of(to_delayed_work(work),
+ struct udc, drd_work);
+
+ if (udc->conn_type) {
+ dev_dbg(udc->dev, "idle -> device\n");
+ start_udc(udc);
+ } else {
+ dev_dbg(udc->dev, "device -> idle\n");
+ stop_udc(udc);
+ }
+}
+
+static int usbd_connect_notify(struct notifier_block *self,
+ unsigned long event, void *ptr)
+{
+ struct udc *udc = container_of(self, struct udc, nb);
+
+ dev_dbg(udc->dev, "%s: event: %lu\n", __func__, event);
+
+ udc->conn_type = event;
+
+ schedule_delayed_work(&udc->drd_work, 0);
+
+ return NOTIFY_OK;
+}
+
+static int udc_plat_probe(struct platform_device *pdev)
+{
+ struct device *dev = &pdev->dev;
+ struct resource *res;
+ struct udc *udc;
+ int ret;
+
+ udc = devm_kzalloc(dev, sizeof(*udc), GFP_KERNEL);
+ if (!udc)
+ return -ENOMEM;
+
+ spin_lock_init(&udc->lock);
+ udc->dev = dev;
+
+ res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+ udc->virt_addr = devm_ioremap_resource(dev, res);
+ if (IS_ERR(udc->regs))
+ return PTR_ERR(udc->regs);
+
+ /* udc csr registers base */
+ udc->csr = udc->virt_addr + UDC_CSR_ADDR;
+
+ /* dev registers base */
+ udc->regs = udc->virt_addr + UDC_DEVCFG_ADDR;
+
+ /* ep registers base */
+ udc->ep_regs = udc->virt_addr + UDC_EPREGS_ADDR;
+
+ /* fifo's base */
+ udc->rxfifo = (u32 __iomem *)(udc->virt_addr + UDC_RXFIFO_ADDR);
+ udc->txfifo = (u32 __iomem *)(udc->virt_addr + UDC_TXFIFO_ADDR);
+
+ udc->phys_addr = (unsigned long)res->start;
+
+ udc->irq = irq_of_parse_and_map(dev->of_node, 0);
+ if (udc->irq <= 0) {
+ dev_err(dev, "Can't parse and map interrupt\n");
+ return -EINVAL;
+ }
+
+ udc->udc_phy = devm_of_phy_get_by_index(dev, dev->of_node, 0);
+ if (IS_ERR(udc->udc_phy)) {
+ dev_err(dev, "Failed to obtain phy from device tree\n");
+ return PTR_ERR(udc->udc_phy);
+ }
+
+ ret = phy_init(udc->udc_phy);
+ if (ret) {
+ dev_err(dev, "UDC phy init failed");
+ return ret;
+ }
+
+ ret = phy_power_on(udc->udc_phy);
+ if (ret) {
+ dev_err(dev, "UDC phy power on failed");
+ phy_exit(udc->udc_phy);
+ return ret;
+ }
+
+ /* Register for extcon if supported */
+ if (of_get_property(dev->of_node, "extcon", NULL)) {
+ udc->edev = extcon_get_edev_by_phandle(dev, 0);
+ if (IS_ERR(udc->edev)) {
+ if (PTR_ERR(udc->edev) == -EPROBE_DEFER)
+ return -EPROBE_DEFER;
+ dev_err(dev, "Invalid or missing extcon\n");
+ ret = PTR_ERR(udc->edev);
+ goto exit_phy;
+ }
+
+ udc->nb.notifier_call = usbd_connect_notify;
+ ret = extcon_register_notifier(udc->edev, EXTCON_USB,
+ &udc->nb);
+ if (ret < 0) {
+ dev_err(dev, "Can't register extcon device\n");
+ goto exit_phy;
+ }
+
+ ret = extcon_get_cable_state_(udc->edev, EXTCON_USB);
+ if (ret < 0) {
+ dev_err(dev, "Can't get cable state\n");
+ goto exit_extcon;
+ } else if (ret) {
+ udc->conn_type = ret;
+ }
+ INIT_DELAYED_WORK(&udc->drd_work, udc_drd_work);
+ }
+
+ /* init dma pools */
+ if (use_dma) {
+ ret = init_dma_pools(udc);
+ if (ret != 0)
+ goto exit_extcon;
+ }
+
+ ret = devm_request_irq(dev, udc->irq, udc_irq, IRQF_SHARED,
+ "snps-udc", udc);
+ if (ret < 0) {
+ dev_err(dev, "Request irq %d failed for UDC\n", udc->irq);
+ goto exit_dma;
+ }
+
+ platform_set_drvdata(pdev, udc);
+ udc->chiprev = UDC_BCM_REV;
+
+ if (udc_probe(udc)) {
+ ret = -ENODEV;
+ goto exit_dma;
+ }
+ dev_info(dev, "Synopsys UDC platform driver probe successful\n");
+
+ return 0;
+
+exit_dma:
+ if (use_dma)
+ free_dma_pools(udc);
+exit_extcon:
+ if (udc->edev)
+ extcon_unregister_notifier(udc->edev, EXTCON_USB, &udc->nb);
+exit_phy:
+ if (udc->udc_phy) {
+ phy_power_off(udc->udc_phy);
+ phy_exit(udc->udc_phy);
+ }
+ return ret;
+}
+
+static int udc_plat_remove(struct platform_device *pdev)
+{
+ struct udc *dev;
+
+ dev = platform_get_drvdata(pdev);
+
+ usb_del_gadget_udc(&udc->gadget);
+ /* gadget driver must not be registered */
+ if (WARN_ON(dev->driver))
+ return 0;
+
+ /* dma pool cleanup */
+ free_dma_pools(dev);
+
+ udc_remove(dev);
+
+ platform_set_drvdata(pdev, NULL);
+
+ if (udc->drd_wq) {
+ flush_workqueue(udc->drd_wq);
+ destroy_workqueue(udc->drd_wq);
+ }
+
+ /* free_udc_dma(pdev, udc); */
+ phy_power_off(udc->udc_phy);
+ phy_exit(udc->udc_phy);
+ extcon_unregister_notifier(udc->edev, EXTCON_USB, &udc->nb);
+
+ dev_info(&pdev->dev, "Synopsys UDC driver removed\n");
+
+ return 0;
+}
+
+#ifdef CONFIG_PM_SLEEP
+static int udc_plat_suspend(struct device *dev)
+{
+ struct udc *udc;
+
+ udc = dev_get_drvdata(dev);
+ usb_disconnect(udc);
+
+ if (extcon_get_cable_state_(udc->edev, EXTCON_USB) > 0) {
+ dev_dbg(udc->dev, "device -> idle\n");
+ stop_udc(udc);
+ }
+ phy_power_off(udc->udc_phy);
+ phy_exit(udc->udc_phy);
+
+ return 0;
+}
+
+static int udc_plat_resume(struct device *dev)
+{
+ struct udc *udc;
+ int ret;
+
+ udc = dev_get_drvdata(dev);
+
+ ret = phy_init(udc->udc_phy);
+ if (ret) {
+ dev_err(udc->dev, "UDC phy init failure");
+ return ret;
+ }
+
+ ret = phy_power_on(udc->udc_phy);
+ if (ret) {
+ dev_err(udc->dev, "UDC phy power on failure");
+ phy_exit(udc->udc_phy);
+ return ret;
+ }
+
+ if (extcon_get_cable_state_(udc->edev, EXTCON_USB) > 0) {
+ dev_dbg(udc->dev, "idle -> device\n");
+ start_udc(udc);
+ }
+
+ return 0;
+}
+static const struct dev_pm_ops udc_plat_pm_ops = {
+ .suspend = udc_plat_suspend,
+ .resume = udc_plat_resume,
+};
+#endif
+
+#if defined(CONFIG_OF)
+static const struct of_device_id of_udc_match[] = {
+ { .compatible = "snps,bcm-ahb-udc", },
+ { }
+};
+MODULE_DEVICE_TABLE(of, of_udc_match);
+#endif
+
+static struct platform_driver udc_plat_driver = {
+ .probe = udc_plat_probe,
+ .remove = udc_plat_remove,
+ .driver = {
+ .name = "snps-udc",
+ .of_match_table = of_match_ptr(of_udc_match),
+#ifdef CONFIG_PM_SLEEP
+ .pm = &udc_plat_pm_ops,
+#endif
+ },
+};
+module_platform_driver(udc_plat_driver);
+
MODULE_DESCRIPTION(UDC_MOD_DESCRIPTION);
MODULE_AUTHOR("Thomas Dahlmann");
MODULE_LICENSE("GPL");
diff --git a/drivers/usb/gadget/udc/amd5536udc.h b/drivers/usb/gadget/udc/amd5536udc.h
index 4638d70..88e1b75 100644
--- a/drivers/usb/gadget/udc/amd5536udc.h
+++ b/drivers/usb/gadget/udc/amd5536udc.h
@@ -22,6 +22,9 @@
#define UDC_HSA0_REV 1
#define UDC_HSB1_REV 2

+/* Broadcom chip rev. */
+#define UDC_BCM_REV 10
+
/*
* SETUP usb commands
* needed, because some SETUP's are handled in hw, but must be passed to
@@ -106,6 +109,7 @@
#define UDC_DEVCTL_BRLEN_MASK 0x00ff0000
#define UDC_DEVCTL_BRLEN_OFS 16

+#define UDC_DEVCTL_SRX_FLUSH 14
#define UDC_DEVCTL_CSR_DONE 13
#define UDC_DEVCTL_DEVNAK 12
#define UDC_DEVCTL_SD 10
@@ -518,6 +522,7 @@ struct udc_ep {
in : 1;
};

+#define USBD_WQ_DELAY_MS msecs_to_jiffies(100)
/* device struct */
struct udc {
struct usb_gadget gadget;
@@ -557,6 +562,16 @@ struct udc {
u16 cur_config;
u16 cur_intf;
u16 cur_alt;
+
+ /* for platform device and extcon support */
+ struct device *dev;
+ struct phy *udc_phy;
+ struct extcon_dev *edev;
+ struct extcon_specific_cable_nb extcon_nb;
+ struct notifier_block nb;
+ struct delayed_work drd_work;
+ struct workqueue_struct *drd_wq;
+ u32 conn_type;
};

#define to_amd5536_udc(g) (container_of((g), struct udc, gadget))
@@ -603,7 +618,7 @@ union udc_setup_data {

/* debug macros ------------------------------------------------------------*/

-#define DBG(udc , args...) dev_dbg(&(udc)->pdev->dev, args)
+#define DBG(udc , args...) dev_dbg(udc->dev, args)

#ifdef UDC_VERBOSE
#define VDBG DBG
--
2.1.0