usb: Introduce DesignWare USB3 DRD Driver

The DesignWare USB3 is a highly
configurable IP Core which can be
instantiated as Dual-Role Device (DRD),
Peripheral Only and Host Only (XHCI)
configurations.

Several other parameters can be configured
like amount of FIFO space, amount of TX and
RX endpoints, amount of Host Interrupters,
etc.

The current driver has been validated with
a virtual model of version 1.73a of that core
and with an FPGA burned with version 1.83a
of the DRD core. We have support for PCIe
bus, which is used on FPGA prototyping, and
for the OMAP5, more adaptation (or glue)
layers can be easily added and the driver
is half prepared to handle any possible
configuration the HW engineer has chosen
considering we have the information on
one of the GHWPARAMS registers to do
runtime checking of certain features.

More runtime checks can, and should, be added
in order to make this driver even more flexible
with regards to number of endpoints, FIFO sizes,
transfer types, etc.

While this supports only the device side, for
now, we will add support for Host side (xHCI -
see the updated series Sebastian has sent [1])
and OTG after we have it all stabilized.

[1] http://marc.info/?l=linux-usb&m=131341992020339&w=2

Signed-off-by: Felipe Balbi <balbi@ti.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

1 files changed, 467 insertions, 0 deletions

diff --git a/drivers/usb/dwc3/core.c b/drivers/usb/dwc3/core.c
new file mode 100644
index 000000000000..443e4fb9b8f3
--- /dev/null
+++ b/drivers/usb/dwc3/core.c
@@ -0,0 +1,467 @@
+/**
+ * core.c - DesignWare USB3 DRD Controller Core file
+ *
+ * Copyright (C) 2010-2011 Texas Instruments Incorporated - http://www.ti.com
+ * All rights reserved.
+ *
+ * Authors: Felipe Balbi <balbi@ti.com>,
+ *          Sebastian Andrzej Siewior <bigeasy@linutronix.de>
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ * 1. Redistributions of source code must retain the above copyright
+ *    notice, this list of conditions, and the following disclaimer,
+ *    without modification.
+ * 2. Redistributions in binary form must reproduce the above copyright
+ *    notice, this list of conditions and the following disclaimer in the
+ *    documentation and/or other materials provided with the distribution.
+ * 3. The names of the above-listed copyright holders may not be used
+ *    to endorse or promote products derived from this software without
+ *    specific prior written permission.
+ *
+ * ALTERNATIVELY, this software may be distributed under the terms of the
+ * GNU General Public License ("GPL") version 2, as published by the Free
+ * Software Foundation.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS
+ * IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO,
+ * THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
+ * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR
+ * CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
+ * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
+ * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
+ * PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF
+ * LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING
+ * NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
+ * SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ */
+
+#include <linux/kernel.h>
+#include <linux/slab.h>
+#include <linux/spinlock.h>
+#include <linux/platform_device.h>
+#include <linux/pm_runtime.h>
+#include <linux/interrupt.h>
+#include <linux/ioport.h>
+#include <linux/io.h>
+#include <linux/list.h>
+#include <linux/delay.h>
+#include <linux/dma-mapping.h>
+
+#include <linux/usb/ch9.h>
+#include <linux/usb/gadget.h>
+
+#include "core.h"
+#include "gadget.h"
+#include "io.h"
+
+#include "debug.h"
+
+/**
+ * dwc3_core_soft_reset - Issues core soft reset and PHY reset
+ * @dwc: pointer to our context structure
+ */
+static void dwc3_core_soft_reset(struct dwc3 *dwc)
+{
+        u32             reg;
+
+        /* Before Resetting PHY, put Core in Reset */
+        reg = dwc3_readl(dwc->regs, DWC3_GCTL);
+        reg |= DWC3_GCTL_CORESOFTRESET;
+        dwc3_writel(dwc->regs, DWC3_GCTL, reg);
+
+        /* Assert USB3 PHY reset */
+        reg = dwc3_readl(dwc->regs, DWC3_GUSB3PIPECTL(0));
+        reg |= DWC3_GUSB3PIPECTL_PHYSOFTRST;
+        dwc3_writel(dwc->regs, DWC3_GUSB3PIPECTL(0), reg);
+
+        /* Assert USB2 PHY reset */
+        reg = dwc3_readl(dwc->regs, DWC3_GUSB2PHYCFG(0));
+        reg |= DWC3_GUSB2PHYCFG_PHYSOFTRST;
+        dwc3_writel(dwc->regs, DWC3_GUSB2PHYCFG(0), reg);
+
+        mdelay(100);
+
+        /* Clear USB3 PHY reset */
+        reg = dwc3_readl(dwc->regs, DWC3_GUSB3PIPECTL(0));
+        reg &= ~DWC3_GUSB3PIPECTL_PHYSOFTRST;
+        dwc3_writel(dwc->regs, DWC3_GUSB3PIPECTL(0), reg);
+
+        /* Clear USB2 PHY reset */
+        reg = dwc3_readl(dwc->regs, DWC3_GUSB2PHYCFG(0));
+        reg &= ~DWC3_GUSB2PHYCFG_PHYSOFTRST;
+        dwc3_writel(dwc->regs, DWC3_GUSB2PHYCFG(0), reg);
+
+        /* After PHYs are stable we can take Core out of reset state */
+        reg = dwc3_readl(dwc->regs, DWC3_GCTL);
+        reg &= ~DWC3_GCTL_CORESOFTRESET;
+        dwc3_writel(dwc->regs, DWC3_GCTL, reg);
+}
+
+/**
+ * dwc3_free_one_event_buffer - Frees one event buffer
+ * @dwc: Pointer to our controller context structure
+ * @evt: Pointer to event buffer to be freed
+ */
+static void dwc3_free_one_event_buffer(struct dwc3 *dwc,
+                struct dwc3_event_buffer *evt)
+{
+        dma_free_coherent(dwc->dev, evt->length, evt->buf, evt->dma);
+        kfree(evt);
+}
+
+/**
+ * dwc3_alloc_one_event_buffer - Allocated one event buffer structure
+ * @dwc: Pointer to our controller context structure
+ * @length: size of the event buffer
+ *
+ * Returns a pointer to the allocated event buffer structure on succes
+ * otherwise ERR_PTR(errno).
+ */
+static struct dwc3_event_buffer *__devinit
+dwc3_alloc_one_event_buffer(struct dwc3 *dwc, unsigned length)
+{
+        struct dwc3_event_buffer        *evt;
+
+        evt = kzalloc(sizeof(*evt), GFP_KERNEL);
+        if (!evt)
+                return ERR_PTR(-ENOMEM);
+
+        evt->dwc        = dwc;
+        evt->length     = length;
+        evt->buf        = dma_alloc_coherent(dwc->dev, length,
+                        &evt->dma, GFP_KERNEL);
+        if (!evt->buf) {
+                kfree(evt);
+                return ERR_PTR(-ENOMEM);
+        }
+
+        return evt;
+}
+
+/**
+ * dwc3_free_event_buffers - frees all allocated event buffers
+ * @dwc: Pointer to our controller context structure
+ */
+static void dwc3_free_event_buffers(struct dwc3 *dwc)
+{
+        struct dwc3_event_buffer        *evt;
+        int i;
+
+        for (i = 0; i < DWC3_EVENT_BUFFERS_NUM; i++) {
+                evt = dwc->ev_buffs[i];
+                if (evt) {
+                        dwc3_free_one_event_buffer(dwc, evt);
+                        dwc->ev_buffs[i] = NULL;
+                }
+        }
+}
+
+/**
+ * dwc3_alloc_event_buffers - Allocates @num event buffers of size @length
+ * @dwc: Pointer to out controller context structure
+ * @num: number of event buffers to allocate
+ * @length: size of event buffer
+ *
+ * Returns 0 on success otherwise negative errno. In error the case, dwc
+ * may contain some buffers allocated but not all which were requested.
+ */
+static int __devinit dwc3_alloc_event_buffers(struct dwc3 *dwc, unsigned num,
+                unsigned length)
+{
+        int                     i;
+
+        for (i = 0; i < num; i++) {
+                struct dwc3_event_buffer        *evt;
+
+                evt = dwc3_alloc_one_event_buffer(dwc, length);
+                if (IS_ERR(evt)) {
+                        dev_err(dwc->dev, "can't allocate event buffer\n");
+                        return PTR_ERR(evt);
+                }
+                dwc->ev_buffs[i] = evt;
+        }
+
+        return 0;
+}
+
+/**
+ * dwc3_event_buffers_setup - setup our allocated event buffers
+ * @dwc: Pointer to out controller context structure
+ *
+ * Returns 0 on success otherwise negative errno.
+ */
+static int __devinit dwc3_event_buffers_setup(struct dwc3 *dwc)
+{
+        struct dwc3_event_buffer        *evt;
+        int                             n;
+
+        for (n = 0; n < DWC3_EVENT_BUFFERS_NUM; n++) {
+                evt = dwc->ev_buffs[n];
+                dev_dbg(dwc->dev, "Event buf %p dma %08llx length %d\n",
+                                evt->buf, (unsigned long long) evt->dma,
+                                evt->length);
+
+                dwc3_writel(dwc->regs, DWC3_GEVNTADRLO(n),
+                                lower_32_bits(evt->dma));
+                dwc3_writel(dwc->regs, DWC3_GEVNTADRHI(n),
+                                upper_32_bits(evt->dma));
+                dwc3_writel(dwc->regs, DWC3_GEVNTSIZ(n),
+                                evt->length & 0xffff);
+                dwc3_writel(dwc->regs, DWC3_GEVNTCOUNT(n), 0);
+        }
+
+        return 0;
+}
+
+static void dwc3_event_buffers_cleanup(struct dwc3 *dwc)
+{
+        struct dwc3_event_buffer        *evt;
+        int                             n;
+
+        for (n = 0; n < DWC3_EVENT_BUFFERS_NUM; n++) {
+                evt = dwc->ev_buffs[n];
+                dwc3_writel(dwc->regs, DWC3_GEVNTADRLO(n), 0);
+                dwc3_writel(dwc->regs, DWC3_GEVNTADRHI(n), 0);
+                dwc3_writel(dwc->regs, DWC3_GEVNTSIZ(n), 0);
+                dwc3_writel(dwc->regs, DWC3_GEVNTCOUNT(n), 0);
+        }
+}
+
+/**
+ * dwc3_core_init - Low-level initialization of DWC3 Core
+ * @dwc: Pointer to our controller context structure
+ *
+ * Returns 0 on success otherwise negative errno.
+ */
+static int __devinit dwc3_core_init(struct dwc3 *dwc)
+{
+        unsigned long           timeout;
+        u32                     reg;
+        int                     ret;
+
+        dwc3_core_soft_reset(dwc);
+
+        /* issue device SoftReset too */
+        timeout = jiffies + msecs_to_jiffies(500);
+        dwc3_writel(dwc->regs, DWC3_DCTL, DWC3_DCTL_CSFTRST);
+        do {
+                reg = dwc3_readl(dwc->regs, DWC3_DCTL);
+                if (!(reg & DWC3_DCTL_CSFTRST))
+                        break;
+
+                if (time_after(jiffies, timeout)) {
+                        dev_err(dwc->dev, "Reset Timed Out\n");
+                        ret = -ETIMEDOUT;
+                        goto err0;
+                }
+
+                cpu_relax();
+        } while (true);
+
+        reg = dwc3_readl(dwc->regs, DWC3_GSNPSID);
+        /* This should read as U3 followed by revision number */
+        if ((reg & DWC3_GSNPSID_MASK) != 0x55330000) {
+                dev_err(dwc->dev, "this is not a DesignWare USB3 DRD Core\n");
+                ret = -ENODEV;
+                goto err0;
+        }
+
+        dwc->revision = reg & DWC3_GSNPSREV_MASK;
+
+        ret = dwc3_alloc_event_buffers(dwc, DWC3_EVENT_BUFFERS_NUM,
+                        DWC3_EVENT_BUFFERS_SIZE);
+        if (ret) {
+                dev_err(dwc->dev, "failed to allocate event buffers\n");
+                ret = -ENOMEM;
+                goto err1;
+        }
+
+        ret = dwc3_event_buffers_setup(dwc);
+        if (ret) {
+                dev_err(dwc->dev, "failed to setup event buffers\n");
+                goto err1;
+        }
+
+        return 0;
+
+err1:
+        dwc3_free_event_buffers(dwc);
+
+err0:
+        return ret;
+}
+
+static void dwc3_core_exit(struct dwc3 *dwc)
+{
+        dwc3_event_buffers_cleanup(dwc);
+        dwc3_free_event_buffers(dwc);
+}
+
+#define DWC3_ALIGN_MASK         (16 - 1)
+
+static int __devinit dwc3_probe(struct platform_device *pdev)
+{
+        const struct platform_device_id *id = platform_get_device_id(pdev);
+        struct resource         *res;
+        struct dwc3             *dwc;
+        void __iomem            *regs;
+        unsigned int            features = id->driver_data;
+        int                     ret = -ENOMEM;
+        int                     irq;
+        void                    *mem;
+
+        mem = kzalloc(sizeof(*dwc) + DWC3_ALIGN_MASK, GFP_KERNEL);
+        if (!mem) {
+                dev_err(&pdev->dev, "not enough memory\n");
+                goto err0;
+        }
+        dwc = PTR_ALIGN(mem, DWC3_ALIGN_MASK + 1);
+        dwc->mem = mem;
+
+        res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+        if (!res) {
+                dev_err(&pdev->dev, "missing resource\n");
+                goto err1;
+        }
+
+        res = request_mem_region(res->start, resource_size(res),
+                        dev_name(&pdev->dev));
+        if (!res) {
+                dev_err(&pdev->dev, "can't request mem region\n");
+                goto err1;
+        }
+
+        regs = ioremap(res->start, resource_size(res));
+        if (!regs) {
+                dev_err(&pdev->dev, "ioremap failed\n");
+                goto err2;
+        }
+
+        irq = platform_get_irq(pdev, 0);
+        if (irq < 0) {
+                dev_err(&pdev->dev, "missing IRQ\n");
+                goto err3;
+        }
+
+        spin_lock_init(&dwc->lock);
+        platform_set_drvdata(pdev, dwc);
+
+        dwc->regs       = regs;
+        dwc->regs_size  = resource_size(res);
+        dwc->dev        = &pdev->dev;
+        dwc->irq        = irq;
+
+        pm_runtime_enable(&pdev->dev);
+        pm_runtime_get_sync(&pdev->dev);
+        pm_runtime_forbid(&pdev->dev);
+
+        ret = dwc3_core_init(dwc);
+        if (ret) {
+                dev_err(&pdev->dev, "failed to initialize core\n");
+                goto err3;
+        }
+
+        if (features & DWC3_HAS_PERIPHERAL) {
+                ret = dwc3_gadget_init(dwc);
+                if (ret) {
+                        dev_err(&pdev->dev, "failed to initialized gadget\n");
+                        goto err4;
+                }
+        }
+
+        ret = dwc3_debugfs_init(dwc);
+        if (ret) {
+                dev_err(&pdev->dev, "failed to initialize debugfs\n");
+                goto err5;
+        }
+
+        pm_runtime_allow(&pdev->dev);
+
+        return 0;
+
+err5:
+        if (features & DWC3_HAS_PERIPHERAL)
+                dwc3_gadget_exit(dwc);
+
+err4:
+        dwc3_core_exit(dwc);
+
+err3:
+        iounmap(regs);
+
+err2:
+        release_mem_region(res->start, resource_size(res));
+
+err1:
+        kfree(dwc->mem);
+
+err0:
+        return ret;
+}
+
+static int __devexit dwc3_remove(struct platform_device *pdev)
+{
+        const struct platform_device_id *id = platform_get_device_id(pdev);
+        struct dwc3     *dwc = platform_get_drvdata(pdev);
+        struct resource *res;
+        unsigned int    features = id->driver_data;
+
+        res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+
+        pm_runtime_put(&pdev->dev);
+        pm_runtime_disable(&pdev->dev);
+
+        dwc3_debugfs_exit(dwc);
+
+        if (features & DWC3_HAS_PERIPHERAL)
+                dwc3_gadget_exit(dwc);
+
+        dwc3_core_exit(dwc);
+        release_mem_region(res->start, resource_size(res));
+        iounmap(dwc->regs);
+        kfree(dwc->mem);
+
+        return 0;
+}
+
+static const struct platform_device_id dwc3_id_table[] __devinitconst = {
+        {
+                .name   = "dwc3-omap",
+                .driver_data = (DWC3_HAS_PERIPHERAL
+                        | DWC3_HAS_XHCI
+                        | DWC3_HAS_OTG),
+        },
+        {
+                .name   = "dwc3-pci",
+                .driver_data = DWC3_HAS_PERIPHERAL,
+        },
+        {  },   /* Terminating Entry */
+};
+MODULE_DEVICE_TABLE(platform, dwc3_id_table);
+
+static struct platform_driver dwc3_driver = {
+        .probe          = dwc3_probe,
+        .remove         = __devexit_p(dwc3_remove),
+        .driver         = {
+                .name   = "dwc3",
+        },
+        .id_table       = dwc3_id_table,
+};
+
+MODULE_AUTHOR("Felipe Balbi <balbi@ti.com>");
+MODULE_LICENSE("Dual BSD/GPL");
+MODULE_DESCRIPTION("DesignWare USB3 DRD Controller Driver");
+
+static int __devinit dwc3_init(void)
+{
+        return platform_driver_register(&dwc3_driver);
+}
+module_init(dwc3_init);
+
+static void __exit dwc3_exit(void)
+{
+        platform_driver_unregister(&dwc3_driver);
+}
+module_exit(dwc3_exit);