File-copy from v4.4.100
This is the result of 'cp' from a linux-stable tree with the 'v4.4.100'
tag checked out (commit 26d6298789e695c9f627ce49a7bbd2286405798a) on
git://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git
Please refer to that tree for all history prior to this point.
Change-Id: I8a9ee2aea93cd29c52c847d0ce33091a73ae6afe
diff --git a/drivers/usb/host/max3421-hcd.c b/drivers/usb/host/max3421-hcd.c
new file mode 100644
index 0000000..bd98706
--- /dev/null
+++ b/drivers/usb/host/max3421-hcd.c
@@ -0,0 +1,1954 @@
+/*
+ * MAX3421 Host Controller driver for USB.
+ *
+ * Author: David Mosberger-Tang <davidm@egauge.net>
+ *
+ * (C) Copyright 2014 David Mosberger-Tang <davidm@egauge.net>
+ *
+ * MAX3421 is a chip implementing a USB 2.0 Full-/Low-Speed host
+ * controller on a SPI bus.
+ *
+ * Based on:
+ * o MAX3421E datasheet
+ * http://datasheets.maximintegrated.com/en/ds/MAX3421E.pdf
+ * o MAX3421E Programming Guide
+ * http://www.hdl.co.jp/ftpdata/utl-001/AN3785.pdf
+ * o gadget/dummy_hcd.c
+ * For USB HCD implementation.
+ * o Arduino MAX3421 driver
+ * https://github.com/felis/USB_Host_Shield_2.0/blob/master/Usb.cpp
+ *
+ * This file is licenced under the GPL v2.
+ *
+ * Important note on worst-case (full-speed) packet size constraints
+ * (See USB 2.0 Section 5.6.3 and following):
+ *
+ * - control: 64 bytes
+ * - isochronous: 1023 bytes
+ * - interrupt: 64 bytes
+ * - bulk: 64 bytes
+ *
+ * Since the MAX3421 FIFO size is 64 bytes, we do not have to work about
+ * multi-FIFO writes/reads for a single USB packet *except* for isochronous
+ * transfers. We don't support isochronous transfers at this time, so we
+ * just assume that a USB packet always fits into a single FIFO buffer.
+ *
+ * NOTE: The June 2006 version of "MAX3421E Programming Guide"
+ * (AN3785) has conflicting info for the RCVDAVIRQ bit:
+ *
+ * The description of RCVDAVIRQ says "The CPU *must* clear
+ * this IRQ bit (by writing a 1 to it) before reading the
+ * RCVFIFO data.
+ *
+ * However, the earlier section on "Programming BULK-IN
+ * Transfers" says * that:
+ *
+ * After the CPU retrieves the data, it clears the
+ * RCVDAVIRQ bit.
+ *
+ * The December 2006 version has been corrected and it consistently
+ * states the second behavior is the correct one.
+ *
+ * Synchronous SPI transactions sleep so we can't perform any such
+ * transactions while holding a spin-lock (and/or while interrupts are
+ * masked). To achieve this, all SPI transactions are issued from a
+ * single thread (max3421_spi_thread).
+ */
+
+#include <linux/jiffies.h>
+#include <linux/module.h>
+#include <linux/spi/spi.h>
+#include <linux/usb.h>
+#include <linux/usb/hcd.h>
+
+#include <linux/platform_data/max3421-hcd.h>
+
+#define DRIVER_DESC "MAX3421 USB Host-Controller Driver"
+#define DRIVER_VERSION "1.0"
+
+/* 11-bit counter that wraps around (USB 2.0 Section 8.3.3): */
+#define USB_MAX_FRAME_NUMBER 0x7ff
+#define USB_MAX_RETRIES 3 /* # of retries before error is reported */
+
+/*
+ * Max. # of times we're willing to retransmit a request immediately in
+ * resposne to a NAK. Afterwards, we fall back on trying once a frame.
+ */
+#define NAK_MAX_FAST_RETRANSMITS 2
+
+#define POWER_BUDGET 500 /* in mA; use 8 for low-power port testing */
+
+/* Port-change mask: */
+#define PORT_C_MASK ((USB_PORT_STAT_C_CONNECTION | \
+ USB_PORT_STAT_C_ENABLE | \
+ USB_PORT_STAT_C_SUSPEND | \
+ USB_PORT_STAT_C_OVERCURRENT | \
+ USB_PORT_STAT_C_RESET) << 16)
+
+enum max3421_rh_state {
+ MAX3421_RH_RESET,
+ MAX3421_RH_SUSPENDED,
+ MAX3421_RH_RUNNING
+};
+
+enum pkt_state {
+ PKT_STATE_SETUP, /* waiting to send setup packet to ctrl pipe */
+ PKT_STATE_TRANSFER, /* waiting to xfer transfer_buffer */
+ PKT_STATE_TERMINATE /* waiting to terminate control transfer */
+};
+
+enum scheduling_pass {
+ SCHED_PASS_PERIODIC,
+ SCHED_PASS_NON_PERIODIC,
+ SCHED_PASS_DONE
+};
+
+/* Bit numbers for max3421_hcd->todo: */
+enum {
+ ENABLE_IRQ = 0,
+ RESET_HCD,
+ RESET_PORT,
+ CHECK_UNLINK,
+ IOPIN_UPDATE
+};
+
+struct max3421_dma_buf {
+ u8 data[2];
+};
+
+struct max3421_hcd {
+ spinlock_t lock;
+
+ struct task_struct *spi_thread;
+
+ struct max3421_hcd *next;
+
+ enum max3421_rh_state rh_state;
+ /* lower 16 bits contain port status, upper 16 bits the change mask: */
+ u32 port_status;
+
+ unsigned active:1;
+
+ struct list_head ep_list; /* list of EP's with work */
+
+ /*
+ * The following are owned by spi_thread (may be accessed by
+ * SPI-thread without acquiring the HCD lock:
+ */
+ u8 rev; /* chip revision */
+ u16 frame_number;
+ /*
+ * kmalloc'd buffers guaranteed to be in separate (DMA)
+ * cache-lines:
+ */
+ struct max3421_dma_buf *tx;
+ struct max3421_dma_buf *rx;
+ /*
+ * URB we're currently processing. Must not be reset to NULL
+ * unless MAX3421E chip is idle:
+ */
+ struct urb *curr_urb;
+ enum scheduling_pass sched_pass;
+ struct usb_device *loaded_dev; /* dev that's loaded into the chip */
+ int loaded_epnum; /* epnum whose toggles are loaded */
+ int urb_done; /* > 0 -> no errors, < 0: errno */
+ size_t curr_len;
+ u8 hien;
+ u8 mode;
+ u8 iopins[2];
+ unsigned long todo;
+#ifdef DEBUG
+ unsigned long err_stat[16];
+#endif
+};
+
+struct max3421_ep {
+ struct usb_host_endpoint *ep;
+ struct list_head ep_list;
+ u32 naks;
+ u16 last_active; /* frame # this ep was last active */
+ enum pkt_state pkt_state;
+ u8 retries;
+ u8 retransmit; /* packet needs retransmission */
+};
+
+static struct max3421_hcd *max3421_hcd_list;
+
+#define MAX3421_FIFO_SIZE 64
+
+#define MAX3421_SPI_DIR_RD 0 /* read register from MAX3421 */
+#define MAX3421_SPI_DIR_WR 1 /* write register to MAX3421 */
+
+/* SPI commands: */
+#define MAX3421_SPI_DIR_SHIFT 1
+#define MAX3421_SPI_REG_SHIFT 3
+
+#define MAX3421_REG_RCVFIFO 1
+#define MAX3421_REG_SNDFIFO 2
+#define MAX3421_REG_SUDFIFO 4
+#define MAX3421_REG_RCVBC 6
+#define MAX3421_REG_SNDBC 7
+#define MAX3421_REG_USBIRQ 13
+#define MAX3421_REG_USBIEN 14
+#define MAX3421_REG_USBCTL 15
+#define MAX3421_REG_CPUCTL 16
+#define MAX3421_REG_PINCTL 17
+#define MAX3421_REG_REVISION 18
+#define MAX3421_REG_IOPINS1 20
+#define MAX3421_REG_IOPINS2 21
+#define MAX3421_REG_GPINIRQ 22
+#define MAX3421_REG_GPINIEN 23
+#define MAX3421_REG_GPINPOL 24
+#define MAX3421_REG_HIRQ 25
+#define MAX3421_REG_HIEN 26
+#define MAX3421_REG_MODE 27
+#define MAX3421_REG_PERADDR 28
+#define MAX3421_REG_HCTL 29
+#define MAX3421_REG_HXFR 30
+#define MAX3421_REG_HRSL 31
+
+enum {
+ MAX3421_USBIRQ_OSCOKIRQ_BIT = 0,
+ MAX3421_USBIRQ_NOVBUSIRQ_BIT = 5,
+ MAX3421_USBIRQ_VBUSIRQ_BIT
+};
+
+enum {
+ MAX3421_CPUCTL_IE_BIT = 0,
+ MAX3421_CPUCTL_PULSEWID0_BIT = 6,
+ MAX3421_CPUCTL_PULSEWID1_BIT
+};
+
+enum {
+ MAX3421_USBCTL_PWRDOWN_BIT = 4,
+ MAX3421_USBCTL_CHIPRES_BIT
+};
+
+enum {
+ MAX3421_PINCTL_GPXA_BIT = 0,
+ MAX3421_PINCTL_GPXB_BIT,
+ MAX3421_PINCTL_POSINT_BIT,
+ MAX3421_PINCTL_INTLEVEL_BIT,
+ MAX3421_PINCTL_FDUPSPI_BIT,
+ MAX3421_PINCTL_EP0INAK_BIT,
+ MAX3421_PINCTL_EP2INAK_BIT,
+ MAX3421_PINCTL_EP3INAK_BIT,
+};
+
+enum {
+ MAX3421_HI_BUSEVENT_BIT = 0, /* bus-reset/-resume */
+ MAX3421_HI_RWU_BIT, /* remote wakeup */
+ MAX3421_HI_RCVDAV_BIT, /* receive FIFO data available */
+ MAX3421_HI_SNDBAV_BIT, /* send buffer available */
+ MAX3421_HI_SUSDN_BIT, /* suspend operation done */
+ MAX3421_HI_CONDET_BIT, /* peripheral connect/disconnect */
+ MAX3421_HI_FRAME_BIT, /* frame generator */
+ MAX3421_HI_HXFRDN_BIT, /* host transfer done */
+};
+
+enum {
+ MAX3421_HCTL_BUSRST_BIT = 0,
+ MAX3421_HCTL_FRMRST_BIT,
+ MAX3421_HCTL_SAMPLEBUS_BIT,
+ MAX3421_HCTL_SIGRSM_BIT,
+ MAX3421_HCTL_RCVTOG0_BIT,
+ MAX3421_HCTL_RCVTOG1_BIT,
+ MAX3421_HCTL_SNDTOG0_BIT,
+ MAX3421_HCTL_SNDTOG1_BIT
+};
+
+enum {
+ MAX3421_MODE_HOST_BIT = 0,
+ MAX3421_MODE_LOWSPEED_BIT,
+ MAX3421_MODE_HUBPRE_BIT,
+ MAX3421_MODE_SOFKAENAB_BIT,
+ MAX3421_MODE_SEPIRQ_BIT,
+ MAX3421_MODE_DELAYISO_BIT,
+ MAX3421_MODE_DMPULLDN_BIT,
+ MAX3421_MODE_DPPULLDN_BIT
+};
+
+enum {
+ MAX3421_HRSL_OK = 0,
+ MAX3421_HRSL_BUSY,
+ MAX3421_HRSL_BADREQ,
+ MAX3421_HRSL_UNDEF,
+ MAX3421_HRSL_NAK,
+ MAX3421_HRSL_STALL,
+ MAX3421_HRSL_TOGERR,
+ MAX3421_HRSL_WRONGPID,
+ MAX3421_HRSL_BADBC,
+ MAX3421_HRSL_PIDERR,
+ MAX3421_HRSL_PKTERR,
+ MAX3421_HRSL_CRCERR,
+ MAX3421_HRSL_KERR,
+ MAX3421_HRSL_JERR,
+ MAX3421_HRSL_TIMEOUT,
+ MAX3421_HRSL_BABBLE,
+ MAX3421_HRSL_RESULT_MASK = 0xf,
+ MAX3421_HRSL_RCVTOGRD_BIT = 4,
+ MAX3421_HRSL_SNDTOGRD_BIT,
+ MAX3421_HRSL_KSTATUS_BIT,
+ MAX3421_HRSL_JSTATUS_BIT
+};
+
+/* Return same error-codes as ohci.h:cc_to_error: */
+static const int hrsl_to_error[] = {
+ [MAX3421_HRSL_OK] = 0,
+ [MAX3421_HRSL_BUSY] = -EINVAL,
+ [MAX3421_HRSL_BADREQ] = -EINVAL,
+ [MAX3421_HRSL_UNDEF] = -EINVAL,
+ [MAX3421_HRSL_NAK] = -EAGAIN,
+ [MAX3421_HRSL_STALL] = -EPIPE,
+ [MAX3421_HRSL_TOGERR] = -EILSEQ,
+ [MAX3421_HRSL_WRONGPID] = -EPROTO,
+ [MAX3421_HRSL_BADBC] = -EREMOTEIO,
+ [MAX3421_HRSL_PIDERR] = -EPROTO,
+ [MAX3421_HRSL_PKTERR] = -EPROTO,
+ [MAX3421_HRSL_CRCERR] = -EILSEQ,
+ [MAX3421_HRSL_KERR] = -EIO,
+ [MAX3421_HRSL_JERR] = -EIO,
+ [MAX3421_HRSL_TIMEOUT] = -ETIME,
+ [MAX3421_HRSL_BABBLE] = -EOVERFLOW
+};
+
+/*
+ * See http://www.beyondlogic.org/usbnutshell/usb4.shtml#Control for a
+ * reasonable overview of how control transfers use the the IN/OUT
+ * tokens.
+ */
+#define MAX3421_HXFR_BULK_IN(ep) (0x00 | (ep)) /* bulk or interrupt */
+#define MAX3421_HXFR_SETUP 0x10
+#define MAX3421_HXFR_BULK_OUT(ep) (0x20 | (ep)) /* bulk or interrupt */
+#define MAX3421_HXFR_ISO_IN(ep) (0x40 | (ep))
+#define MAX3421_HXFR_ISO_OUT(ep) (0x60 | (ep))
+#define MAX3421_HXFR_HS_IN 0x80 /* handshake in */
+#define MAX3421_HXFR_HS_OUT 0xa0 /* handshake out */
+
+#define field(val, bit) ((val) << (bit))
+
+static inline s16
+frame_diff(u16 left, u16 right)
+{
+ return ((unsigned) (left - right)) % (USB_MAX_FRAME_NUMBER + 1);
+}
+
+static inline struct max3421_hcd *
+hcd_to_max3421(struct usb_hcd *hcd)
+{
+ return (struct max3421_hcd *) hcd->hcd_priv;
+}
+
+static inline struct usb_hcd *
+max3421_to_hcd(struct max3421_hcd *max3421_hcd)
+{
+ return container_of((void *) max3421_hcd, struct usb_hcd, hcd_priv);
+}
+
+static u8
+spi_rd8(struct usb_hcd *hcd, unsigned int reg)
+{
+ struct max3421_hcd *max3421_hcd = hcd_to_max3421(hcd);
+ struct spi_device *spi = to_spi_device(hcd->self.controller);
+ struct spi_transfer transfer;
+ struct spi_message msg;
+
+ memset(&transfer, 0, sizeof(transfer));
+
+ spi_message_init(&msg);
+
+ max3421_hcd->tx->data[0] =
+ (field(reg, MAX3421_SPI_REG_SHIFT) |
+ field(MAX3421_SPI_DIR_RD, MAX3421_SPI_DIR_SHIFT));
+
+ transfer.tx_buf = max3421_hcd->tx->data;
+ transfer.rx_buf = max3421_hcd->rx->data;
+ transfer.len = 2;
+
+ spi_message_add_tail(&transfer, &msg);
+ spi_sync(spi, &msg);
+
+ return max3421_hcd->rx->data[1];
+}
+
+static void
+spi_wr8(struct usb_hcd *hcd, unsigned int reg, u8 val)
+{
+ struct spi_device *spi = to_spi_device(hcd->self.controller);
+ struct max3421_hcd *max3421_hcd = hcd_to_max3421(hcd);
+ struct spi_transfer transfer;
+ struct spi_message msg;
+
+ memset(&transfer, 0, sizeof(transfer));
+
+ spi_message_init(&msg);
+
+ max3421_hcd->tx->data[0] =
+ (field(reg, MAX3421_SPI_REG_SHIFT) |
+ field(MAX3421_SPI_DIR_WR, MAX3421_SPI_DIR_SHIFT));
+ max3421_hcd->tx->data[1] = val;
+
+ transfer.tx_buf = max3421_hcd->tx->data;
+ transfer.len = 2;
+
+ spi_message_add_tail(&transfer, &msg);
+ spi_sync(spi, &msg);
+}
+
+static void
+spi_rd_buf(struct usb_hcd *hcd, unsigned int reg, void *buf, size_t len)
+{
+ struct spi_device *spi = to_spi_device(hcd->self.controller);
+ struct max3421_hcd *max3421_hcd = hcd_to_max3421(hcd);
+ struct spi_transfer transfer[2];
+ struct spi_message msg;
+
+ memset(transfer, 0, sizeof(transfer));
+
+ spi_message_init(&msg);
+
+ max3421_hcd->tx->data[0] =
+ (field(reg, MAX3421_SPI_REG_SHIFT) |
+ field(MAX3421_SPI_DIR_RD, MAX3421_SPI_DIR_SHIFT));
+ transfer[0].tx_buf = max3421_hcd->tx->data;
+ transfer[0].len = 1;
+
+ transfer[1].rx_buf = buf;
+ transfer[1].len = len;
+
+ spi_message_add_tail(&transfer[0], &msg);
+ spi_message_add_tail(&transfer[1], &msg);
+ spi_sync(spi, &msg);
+}
+
+static void
+spi_wr_buf(struct usb_hcd *hcd, unsigned int reg, void *buf, size_t len)
+{
+ struct spi_device *spi = to_spi_device(hcd->self.controller);
+ struct max3421_hcd *max3421_hcd = hcd_to_max3421(hcd);
+ struct spi_transfer transfer[2];
+ struct spi_message msg;
+
+ memset(transfer, 0, sizeof(transfer));
+
+ spi_message_init(&msg);
+
+ max3421_hcd->tx->data[0] =
+ (field(reg, MAX3421_SPI_REG_SHIFT) |
+ field(MAX3421_SPI_DIR_WR, MAX3421_SPI_DIR_SHIFT));
+
+ transfer[0].tx_buf = max3421_hcd->tx->data;
+ transfer[0].len = 1;
+
+ transfer[1].tx_buf = buf;
+ transfer[1].len = len;
+
+ spi_message_add_tail(&transfer[0], &msg);
+ spi_message_add_tail(&transfer[1], &msg);
+ spi_sync(spi, &msg);
+}
+
+/*
+ * Figure out the correct setting for the LOWSPEED and HUBPRE mode
+ * bits. The HUBPRE bit needs to be set when MAX3421E operates at
+ * full speed, but it's talking to a low-speed device (i.e., through a
+ * hub). Setting that bit ensures that every low-speed packet is
+ * preceded by a full-speed PRE PID. Possible configurations:
+ *
+ * Hub speed: Device speed: => LOWSPEED bit: HUBPRE bit:
+ * FULL FULL => 0 0
+ * FULL LOW => 1 1
+ * LOW LOW => 1 0
+ * LOW FULL => 1 0
+ */
+static void
+max3421_set_speed(struct usb_hcd *hcd, struct usb_device *dev)
+{
+ struct max3421_hcd *max3421_hcd = hcd_to_max3421(hcd);
+ u8 mode_lowspeed, mode_hubpre, mode = max3421_hcd->mode;
+
+ mode_lowspeed = BIT(MAX3421_MODE_LOWSPEED_BIT);
+ mode_hubpre = BIT(MAX3421_MODE_HUBPRE_BIT);
+ if (max3421_hcd->port_status & USB_PORT_STAT_LOW_SPEED) {
+ mode |= mode_lowspeed;
+ mode &= ~mode_hubpre;
+ } else if (dev->speed == USB_SPEED_LOW) {
+ mode |= mode_lowspeed | mode_hubpre;
+ } else {
+ mode &= ~(mode_lowspeed | mode_hubpre);
+ }
+ if (mode != max3421_hcd->mode) {
+ max3421_hcd->mode = mode;
+ spi_wr8(hcd, MAX3421_REG_MODE, max3421_hcd->mode);
+ }
+
+}
+
+/*
+ * Caller must NOT hold HCD spinlock.
+ */
+static void
+max3421_set_address(struct usb_hcd *hcd, struct usb_device *dev, int epnum,
+ int force_toggles)
+{
+ struct max3421_hcd *max3421_hcd = hcd_to_max3421(hcd);
+ int old_epnum, same_ep, rcvtog, sndtog;
+ struct usb_device *old_dev;
+ u8 hctl;
+
+ old_dev = max3421_hcd->loaded_dev;
+ old_epnum = max3421_hcd->loaded_epnum;
+
+ same_ep = (dev == old_dev && epnum == old_epnum);
+ if (same_ep && !force_toggles)
+ return;
+
+ if (old_dev && !same_ep) {
+ /* save the old end-points toggles: */
+ u8 hrsl = spi_rd8(hcd, MAX3421_REG_HRSL);
+
+ rcvtog = (hrsl >> MAX3421_HRSL_RCVTOGRD_BIT) & 1;
+ sndtog = (hrsl >> MAX3421_HRSL_SNDTOGRD_BIT) & 1;
+
+ /* no locking: HCD (i.e., we) own toggles, don't we? */
+ usb_settoggle(old_dev, old_epnum, 0, rcvtog);
+ usb_settoggle(old_dev, old_epnum, 1, sndtog);
+ }
+ /* setup new endpoint's toggle bits: */
+ rcvtog = usb_gettoggle(dev, epnum, 0);
+ sndtog = usb_gettoggle(dev, epnum, 1);
+ hctl = (BIT(rcvtog + MAX3421_HCTL_RCVTOG0_BIT) |
+ BIT(sndtog + MAX3421_HCTL_SNDTOG0_BIT));
+
+ max3421_hcd->loaded_epnum = epnum;
+ spi_wr8(hcd, MAX3421_REG_HCTL, hctl);
+
+ /*
+ * Note: devnum for one and the same device can change during
+ * address-assignment so it's best to just always load the
+ * address whenever the end-point changed/was forced.
+ */
+ max3421_hcd->loaded_dev = dev;
+ spi_wr8(hcd, MAX3421_REG_PERADDR, dev->devnum);
+}
+
+static int
+max3421_ctrl_setup(struct usb_hcd *hcd, struct urb *urb)
+{
+ spi_wr_buf(hcd, MAX3421_REG_SUDFIFO, urb->setup_packet, 8);
+ return MAX3421_HXFR_SETUP;
+}
+
+static int
+max3421_transfer_in(struct usb_hcd *hcd, struct urb *urb)
+{
+ struct max3421_hcd *max3421_hcd = hcd_to_max3421(hcd);
+ int epnum = usb_pipeendpoint(urb->pipe);
+
+ max3421_hcd->curr_len = 0;
+ max3421_hcd->hien |= BIT(MAX3421_HI_RCVDAV_BIT);
+ return MAX3421_HXFR_BULK_IN(epnum);
+}
+
+static int
+max3421_transfer_out(struct usb_hcd *hcd, struct urb *urb, int fast_retransmit)
+{
+ struct spi_device *spi = to_spi_device(hcd->self.controller);
+ struct max3421_hcd *max3421_hcd = hcd_to_max3421(hcd);
+ int epnum = usb_pipeendpoint(urb->pipe);
+ u32 max_packet;
+ void *src;
+
+ src = urb->transfer_buffer + urb->actual_length;
+
+ if (fast_retransmit) {
+ if (max3421_hcd->rev == 0x12) {
+ /* work around rev 0x12 bug: */
+ spi_wr8(hcd, MAX3421_REG_SNDBC, 0);
+ spi_wr8(hcd, MAX3421_REG_SNDFIFO, ((u8 *) src)[0]);
+ spi_wr8(hcd, MAX3421_REG_SNDBC, max3421_hcd->curr_len);
+ }
+ return MAX3421_HXFR_BULK_OUT(epnum);
+ }
+
+ max_packet = usb_maxpacket(urb->dev, urb->pipe, 1);
+
+ if (max_packet > MAX3421_FIFO_SIZE) {
+ /*
+ * We do not support isochronous transfers at this
+ * time.
+ */
+ dev_err(&spi->dev,
+ "%s: packet-size of %u too big (limit is %u bytes)",
+ __func__, max_packet, MAX3421_FIFO_SIZE);
+ max3421_hcd->urb_done = -EMSGSIZE;
+ return -EMSGSIZE;
+ }
+ max3421_hcd->curr_len = min((urb->transfer_buffer_length -
+ urb->actual_length), max_packet);
+
+ spi_wr_buf(hcd, MAX3421_REG_SNDFIFO, src, max3421_hcd->curr_len);
+ spi_wr8(hcd, MAX3421_REG_SNDBC, max3421_hcd->curr_len);
+ return MAX3421_HXFR_BULK_OUT(epnum);
+}
+
+/*
+ * Issue the next host-transfer command.
+ * Caller must NOT hold HCD spinlock.
+ */
+static void
+max3421_next_transfer(struct usb_hcd *hcd, int fast_retransmit)
+{
+ struct max3421_hcd *max3421_hcd = hcd_to_max3421(hcd);
+ struct urb *urb = max3421_hcd->curr_urb;
+ struct max3421_ep *max3421_ep;
+ int cmd = -EINVAL;
+
+ if (!urb)
+ return; /* nothing to do */
+
+ max3421_ep = urb->ep->hcpriv;
+
+ switch (max3421_ep->pkt_state) {
+ case PKT_STATE_SETUP:
+ cmd = max3421_ctrl_setup(hcd, urb);
+ break;
+
+ case PKT_STATE_TRANSFER:
+ if (usb_urb_dir_in(urb))
+ cmd = max3421_transfer_in(hcd, urb);
+ else
+ cmd = max3421_transfer_out(hcd, urb, fast_retransmit);
+ break;
+
+ case PKT_STATE_TERMINATE:
+ /*
+ * IN transfers are terminated with HS_OUT token,
+ * OUT transfers with HS_IN:
+ */
+ if (usb_urb_dir_in(urb))
+ cmd = MAX3421_HXFR_HS_OUT;
+ else
+ cmd = MAX3421_HXFR_HS_IN;
+ break;
+ }
+
+ if (cmd < 0)
+ return;
+
+ /* issue the command and wait for host-xfer-done interrupt: */
+
+ spi_wr8(hcd, MAX3421_REG_HXFR, cmd);
+ max3421_hcd->hien |= BIT(MAX3421_HI_HXFRDN_BIT);
+}
+
+/*
+ * Find the next URB to process and start its execution.
+ *
+ * At this time, we do not anticipate ever connecting a USB hub to the
+ * MAX3421 chip, so at most USB device can be connected and we can use
+ * a simplistic scheduler: at the start of a frame, schedule all
+ * periodic transfers. Once that is done, use the remainder of the
+ * frame to process non-periodic (bulk & control) transfers.
+ *
+ * Preconditions:
+ * o Caller must NOT hold HCD spinlock.
+ * o max3421_hcd->curr_urb MUST BE NULL.
+ * o MAX3421E chip must be idle.
+ */
+static int
+max3421_select_and_start_urb(struct usb_hcd *hcd)
+{
+ struct spi_device *spi = to_spi_device(hcd->self.controller);
+ struct max3421_hcd *max3421_hcd = hcd_to_max3421(hcd);
+ struct urb *urb, *curr_urb = NULL;
+ struct max3421_ep *max3421_ep;
+ int epnum, force_toggles = 0;
+ struct usb_host_endpoint *ep;
+ struct list_head *pos;
+ unsigned long flags;
+
+ spin_lock_irqsave(&max3421_hcd->lock, flags);
+
+ for (;
+ max3421_hcd->sched_pass < SCHED_PASS_DONE;
+ ++max3421_hcd->sched_pass)
+ list_for_each(pos, &max3421_hcd->ep_list) {
+ urb = NULL;
+ max3421_ep = container_of(pos, struct max3421_ep,
+ ep_list);
+ ep = max3421_ep->ep;
+
+ switch (usb_endpoint_type(&ep->desc)) {
+ case USB_ENDPOINT_XFER_ISOC:
+ case USB_ENDPOINT_XFER_INT:
+ if (max3421_hcd->sched_pass !=
+ SCHED_PASS_PERIODIC)
+ continue;
+ break;
+
+ case USB_ENDPOINT_XFER_CONTROL:
+ case USB_ENDPOINT_XFER_BULK:
+ if (max3421_hcd->sched_pass !=
+ SCHED_PASS_NON_PERIODIC)
+ continue;
+ break;
+ }
+
+ if (list_empty(&ep->urb_list))
+ continue; /* nothing to do */
+ urb = list_first_entry(&ep->urb_list, struct urb,
+ urb_list);
+ if (urb->unlinked) {
+ dev_dbg(&spi->dev, "%s: URB %p unlinked=%d",
+ __func__, urb, urb->unlinked);
+ max3421_hcd->curr_urb = urb;
+ max3421_hcd->urb_done = 1;
+ spin_unlock_irqrestore(&max3421_hcd->lock,
+ flags);
+ return 1;
+ }
+
+ switch (usb_endpoint_type(&ep->desc)) {
+ case USB_ENDPOINT_XFER_CONTROL:
+ /*
+ * Allow one control transaction per
+ * frame per endpoint:
+ */
+ if (frame_diff(max3421_ep->last_active,
+ max3421_hcd->frame_number) == 0)
+ continue;
+ break;
+
+ case USB_ENDPOINT_XFER_BULK:
+ if (max3421_ep->retransmit
+ && (frame_diff(max3421_ep->last_active,
+ max3421_hcd->frame_number)
+ == 0))
+ /*
+ * We already tried this EP
+ * during this frame and got a
+ * NAK or error; wait for next frame
+ */
+ continue;
+ break;
+
+ case USB_ENDPOINT_XFER_ISOC:
+ case USB_ENDPOINT_XFER_INT:
+ if (frame_diff(max3421_hcd->frame_number,
+ max3421_ep->last_active)
+ < urb->interval)
+ /*
+ * We already processed this
+ * end-point in the current
+ * frame
+ */
+ continue;
+ break;
+ }
+
+ /* move current ep to tail: */
+ list_move_tail(pos, &max3421_hcd->ep_list);
+ curr_urb = urb;
+ goto done;
+ }
+done:
+ if (!curr_urb) {
+ spin_unlock_irqrestore(&max3421_hcd->lock, flags);
+ return 0;
+ }
+
+ urb = max3421_hcd->curr_urb = curr_urb;
+ epnum = usb_endpoint_num(&urb->ep->desc);
+ if (max3421_ep->retransmit)
+ /* restart (part of) a USB transaction: */
+ max3421_ep->retransmit = 0;
+ else {
+ /* start USB transaction: */
+ if (usb_endpoint_xfer_control(&ep->desc)) {
+ /*
+ * See USB 2.0 spec section 8.6.1
+ * Initialization via SETUP Token:
+ */
+ usb_settoggle(urb->dev, epnum, 0, 1);
+ usb_settoggle(urb->dev, epnum, 1, 1);
+ max3421_ep->pkt_state = PKT_STATE_SETUP;
+ force_toggles = 1;
+ } else
+ max3421_ep->pkt_state = PKT_STATE_TRANSFER;
+ }
+
+ spin_unlock_irqrestore(&max3421_hcd->lock, flags);
+
+ max3421_ep->last_active = max3421_hcd->frame_number;
+ max3421_set_address(hcd, urb->dev, epnum, force_toggles);
+ max3421_set_speed(hcd, urb->dev);
+ max3421_next_transfer(hcd, 0);
+ return 1;
+}
+
+/*
+ * Check all endpoints for URBs that got unlinked.
+ *
+ * Caller must NOT hold HCD spinlock.
+ */
+static int
+max3421_check_unlink(struct usb_hcd *hcd)
+{
+ struct spi_device *spi = to_spi_device(hcd->self.controller);
+ struct max3421_hcd *max3421_hcd = hcd_to_max3421(hcd);
+ struct list_head *pos, *upos, *next_upos;
+ struct max3421_ep *max3421_ep;
+ struct usb_host_endpoint *ep;
+ struct urb *urb;
+ unsigned long flags;
+ int retval = 0;
+
+ spin_lock_irqsave(&max3421_hcd->lock, flags);
+ list_for_each(pos, &max3421_hcd->ep_list) {
+ max3421_ep = container_of(pos, struct max3421_ep, ep_list);
+ ep = max3421_ep->ep;
+ list_for_each_safe(upos, next_upos, &ep->urb_list) {
+ urb = container_of(upos, struct urb, urb_list);
+ if (urb->unlinked) {
+ retval = 1;
+ dev_dbg(&spi->dev, "%s: URB %p unlinked=%d",
+ __func__, urb, urb->unlinked);
+ usb_hcd_unlink_urb_from_ep(hcd, urb);
+ spin_unlock_irqrestore(&max3421_hcd->lock,
+ flags);
+ usb_hcd_giveback_urb(hcd, urb, 0);
+ spin_lock_irqsave(&max3421_hcd->lock, flags);
+ }
+ }
+ }
+ spin_unlock_irqrestore(&max3421_hcd->lock, flags);
+ return retval;
+}
+
+/*
+ * Caller must NOT hold HCD spinlock.
+ */
+static void
+max3421_slow_retransmit(struct usb_hcd *hcd)
+{
+ struct max3421_hcd *max3421_hcd = hcd_to_max3421(hcd);
+ struct urb *urb = max3421_hcd->curr_urb;
+ struct max3421_ep *max3421_ep;
+
+ max3421_ep = urb->ep->hcpriv;
+ max3421_ep->retransmit = 1;
+ max3421_hcd->curr_urb = NULL;
+}
+
+/*
+ * Caller must NOT hold HCD spinlock.
+ */
+static void
+max3421_recv_data_available(struct usb_hcd *hcd)
+{
+ struct max3421_hcd *max3421_hcd = hcd_to_max3421(hcd);
+ struct urb *urb = max3421_hcd->curr_urb;
+ size_t remaining, transfer_size;
+ u8 rcvbc;
+
+ rcvbc = spi_rd8(hcd, MAX3421_REG_RCVBC);
+
+ if (rcvbc > MAX3421_FIFO_SIZE)
+ rcvbc = MAX3421_FIFO_SIZE;
+ if (urb->actual_length >= urb->transfer_buffer_length)
+ remaining = 0;
+ else
+ remaining = urb->transfer_buffer_length - urb->actual_length;
+ transfer_size = rcvbc;
+ if (transfer_size > remaining)
+ transfer_size = remaining;
+ if (transfer_size > 0) {
+ void *dst = urb->transfer_buffer + urb->actual_length;
+
+ spi_rd_buf(hcd, MAX3421_REG_RCVFIFO, dst, transfer_size);
+ urb->actual_length += transfer_size;
+ max3421_hcd->curr_len = transfer_size;
+ }
+
+ /* ack the RCVDAV irq now that the FIFO has been read: */
+ spi_wr8(hcd, MAX3421_REG_HIRQ, BIT(MAX3421_HI_RCVDAV_BIT));
+}
+
+static void
+max3421_handle_error(struct usb_hcd *hcd, u8 hrsl)
+{
+ struct spi_device *spi = to_spi_device(hcd->self.controller);
+ struct max3421_hcd *max3421_hcd = hcd_to_max3421(hcd);
+ u8 result_code = hrsl & MAX3421_HRSL_RESULT_MASK;
+ struct urb *urb = max3421_hcd->curr_urb;
+ struct max3421_ep *max3421_ep = urb->ep->hcpriv;
+ int switch_sndfifo;
+
+ /*
+ * If an OUT command results in any response other than OK
+ * (i.e., error or NAK), we have to perform a dummy-write to
+ * SNDBC so the FIFO gets switched back to us. Otherwise, we
+ * get out of sync with the SNDFIFO double buffer.
+ */
+ switch_sndfifo = (max3421_ep->pkt_state == PKT_STATE_TRANSFER &&
+ usb_urb_dir_out(urb));
+
+ switch (result_code) {
+ case MAX3421_HRSL_OK:
+ return; /* this shouldn't happen */
+
+ case MAX3421_HRSL_WRONGPID: /* received wrong PID */
+ case MAX3421_HRSL_BUSY: /* SIE busy */
+ case MAX3421_HRSL_BADREQ: /* bad val in HXFR */
+ case MAX3421_HRSL_UNDEF: /* reserved */
+ case MAX3421_HRSL_KERR: /* K-state instead of response */
+ case MAX3421_HRSL_JERR: /* J-state instead of response */
+ /*
+ * packet experienced an error that we cannot recover
+ * from; report error
+ */
+ max3421_hcd->urb_done = hrsl_to_error[result_code];
+ dev_dbg(&spi->dev, "%s: unexpected error HRSL=0x%02x",
+ __func__, hrsl);
+ break;
+
+ case MAX3421_HRSL_TOGERR:
+ if (usb_urb_dir_in(urb))
+ ; /* don't do anything (device will switch toggle) */
+ else {
+ /* flip the send toggle bit: */
+ int sndtog = (hrsl >> MAX3421_HRSL_SNDTOGRD_BIT) & 1;
+
+ sndtog ^= 1;
+ spi_wr8(hcd, MAX3421_REG_HCTL,
+ BIT(sndtog + MAX3421_HCTL_SNDTOG0_BIT));
+ }
+ /* FALL THROUGH */
+ case MAX3421_HRSL_BADBC: /* bad byte count */
+ case MAX3421_HRSL_PIDERR: /* received PID is corrupted */
+ case MAX3421_HRSL_PKTERR: /* packet error (stuff, EOP) */
+ case MAX3421_HRSL_CRCERR: /* CRC error */
+ case MAX3421_HRSL_BABBLE: /* device talked too long */
+ case MAX3421_HRSL_TIMEOUT:
+ if (max3421_ep->retries++ < USB_MAX_RETRIES)
+ /* retry the packet again in the next frame */
+ max3421_slow_retransmit(hcd);
+ else {
+ /* Based on ohci.h cc_to_err[]: */
+ max3421_hcd->urb_done = hrsl_to_error[result_code];
+ dev_dbg(&spi->dev, "%s: unexpected error HRSL=0x%02x",
+ __func__, hrsl);
+ }
+ break;
+
+ case MAX3421_HRSL_STALL:
+ dev_dbg(&spi->dev, "%s: unexpected error HRSL=0x%02x",
+ __func__, hrsl);
+ max3421_hcd->urb_done = hrsl_to_error[result_code];
+ break;
+
+ case MAX3421_HRSL_NAK:
+ /*
+ * Device wasn't ready for data or has no data
+ * available: retry the packet again.
+ */
+ if (max3421_ep->naks++ < NAK_MAX_FAST_RETRANSMITS) {
+ max3421_next_transfer(hcd, 1);
+ switch_sndfifo = 0;
+ } else
+ max3421_slow_retransmit(hcd);
+ break;
+ }
+ if (switch_sndfifo)
+ spi_wr8(hcd, MAX3421_REG_SNDBC, 0);
+}
+
+/*
+ * Caller must NOT hold HCD spinlock.
+ */
+static int
+max3421_transfer_in_done(struct usb_hcd *hcd, struct urb *urb)
+{
+ struct spi_device *spi = to_spi_device(hcd->self.controller);
+ struct max3421_hcd *max3421_hcd = hcd_to_max3421(hcd);
+ u32 max_packet;
+
+ if (urb->actual_length >= urb->transfer_buffer_length)
+ return 1; /* read is complete, so we're done */
+
+ /*
+ * USB 2.0 Section 5.3.2 Pipes: packets must be full size
+ * except for last one.
+ */
+ max_packet = usb_maxpacket(urb->dev, urb->pipe, 0);
+ if (max_packet > MAX3421_FIFO_SIZE) {
+ /*
+ * We do not support isochronous transfers at this
+ * time...
+ */
+ dev_err(&spi->dev,
+ "%s: packet-size of %u too big (limit is %u bytes)",
+ __func__, max_packet, MAX3421_FIFO_SIZE);
+ return -EINVAL;
+ }
+
+ if (max3421_hcd->curr_len < max_packet) {
+ if (urb->transfer_flags & URB_SHORT_NOT_OK) {
+ /*
+ * remaining > 0 and received an
+ * unexpected partial packet ->
+ * error
+ */
+ return -EREMOTEIO;
+ } else
+ /* short read, but it's OK */
+ return 1;
+ }
+ return 0; /* not done */
+}
+
+/*
+ * Caller must NOT hold HCD spinlock.
+ */
+static int
+max3421_transfer_out_done(struct usb_hcd *hcd, struct urb *urb)
+{
+ struct max3421_hcd *max3421_hcd = hcd_to_max3421(hcd);
+
+ urb->actual_length += max3421_hcd->curr_len;
+ if (urb->actual_length < urb->transfer_buffer_length)
+ return 0;
+ if (urb->transfer_flags & URB_ZERO_PACKET) {
+ /*
+ * Some hardware needs a zero-size packet at the end
+ * of a bulk-out transfer if the last transfer was a
+ * full-sized packet (i.e., such hardware use <
+ * max_packet as an indicator that the end of the
+ * packet has been reached).
+ */
+ u32 max_packet = usb_maxpacket(urb->dev, urb->pipe, 1);
+
+ if (max3421_hcd->curr_len == max_packet)
+ return 0;
+ }
+ return 1;
+}
+
+/*
+ * Caller must NOT hold HCD spinlock.
+ */
+static void
+max3421_host_transfer_done(struct usb_hcd *hcd)
+{
+ struct max3421_hcd *max3421_hcd = hcd_to_max3421(hcd);
+ struct urb *urb = max3421_hcd->curr_urb;
+ struct max3421_ep *max3421_ep;
+ u8 result_code, hrsl;
+ int urb_done = 0;
+
+ max3421_hcd->hien &= ~(BIT(MAX3421_HI_HXFRDN_BIT) |
+ BIT(MAX3421_HI_RCVDAV_BIT));
+
+ hrsl = spi_rd8(hcd, MAX3421_REG_HRSL);
+ result_code = hrsl & MAX3421_HRSL_RESULT_MASK;
+
+#ifdef DEBUG
+ ++max3421_hcd->err_stat[result_code];
+#endif
+
+ max3421_ep = urb->ep->hcpriv;
+
+ if (unlikely(result_code != MAX3421_HRSL_OK)) {
+ max3421_handle_error(hcd, hrsl);
+ return;
+ }
+
+ max3421_ep->naks = 0;
+ max3421_ep->retries = 0;
+ switch (max3421_ep->pkt_state) {
+
+ case PKT_STATE_SETUP:
+ if (urb->transfer_buffer_length > 0)
+ max3421_ep->pkt_state = PKT_STATE_TRANSFER;
+ else
+ max3421_ep->pkt_state = PKT_STATE_TERMINATE;
+ break;
+
+ case PKT_STATE_TRANSFER:
+ if (usb_urb_dir_in(urb))
+ urb_done = max3421_transfer_in_done(hcd, urb);
+ else
+ urb_done = max3421_transfer_out_done(hcd, urb);
+ if (urb_done > 0 && usb_pipetype(urb->pipe) == PIPE_CONTROL) {
+ /*
+ * We aren't really done - we still need to
+ * terminate the control transfer:
+ */
+ max3421_hcd->urb_done = urb_done = 0;
+ max3421_ep->pkt_state = PKT_STATE_TERMINATE;
+ }
+ break;
+
+ case PKT_STATE_TERMINATE:
+ urb_done = 1;
+ break;
+ }
+
+ if (urb_done)
+ max3421_hcd->urb_done = urb_done;
+ else
+ max3421_next_transfer(hcd, 0);
+}
+
+/*
+ * Caller must NOT hold HCD spinlock.
+ */
+static void
+max3421_detect_conn(struct usb_hcd *hcd)
+{
+ struct max3421_hcd *max3421_hcd = hcd_to_max3421(hcd);
+ unsigned int jk, have_conn = 0;
+ u32 old_port_status, chg;
+ unsigned long flags;
+ u8 hrsl, mode;
+
+ hrsl = spi_rd8(hcd, MAX3421_REG_HRSL);
+
+ jk = ((((hrsl >> MAX3421_HRSL_JSTATUS_BIT) & 1) << 0) |
+ (((hrsl >> MAX3421_HRSL_KSTATUS_BIT) & 1) << 1));
+
+ mode = max3421_hcd->mode;
+
+ switch (jk) {
+ case 0x0: /* SE0: disconnect */
+ /*
+ * Turn off SOFKAENAB bit to avoid getting interrupt
+ * every milli-second:
+ */
+ mode &= ~BIT(MAX3421_MODE_SOFKAENAB_BIT);
+ break;
+
+ case 0x1: /* J=0,K=1: low-speed (in full-speed or vice versa) */
+ case 0x2: /* J=1,K=0: full-speed (in full-speed or vice versa) */
+ if (jk == 0x2)
+ /* need to switch to the other speed: */
+ mode ^= BIT(MAX3421_MODE_LOWSPEED_BIT);
+ /* turn on SOFKAENAB bit: */
+ mode |= BIT(MAX3421_MODE_SOFKAENAB_BIT);
+ have_conn = 1;
+ break;
+
+ case 0x3: /* illegal */
+ break;
+ }
+
+ max3421_hcd->mode = mode;
+ spi_wr8(hcd, MAX3421_REG_MODE, max3421_hcd->mode);
+
+ spin_lock_irqsave(&max3421_hcd->lock, flags);
+ old_port_status = max3421_hcd->port_status;
+ if (have_conn)
+ max3421_hcd->port_status |= USB_PORT_STAT_CONNECTION;
+ else
+ max3421_hcd->port_status &= ~USB_PORT_STAT_CONNECTION;
+ if (mode & BIT(MAX3421_MODE_LOWSPEED_BIT))
+ max3421_hcd->port_status |= USB_PORT_STAT_LOW_SPEED;
+ else
+ max3421_hcd->port_status &= ~USB_PORT_STAT_LOW_SPEED;
+ chg = (old_port_status ^ max3421_hcd->port_status);
+ max3421_hcd->port_status |= chg << 16;
+ spin_unlock_irqrestore(&max3421_hcd->lock, flags);
+}
+
+static irqreturn_t
+max3421_irq_handler(int irq, void *dev_id)
+{
+ struct usb_hcd *hcd = dev_id;
+ struct spi_device *spi = to_spi_device(hcd->self.controller);
+ struct max3421_hcd *max3421_hcd = hcd_to_max3421(hcd);
+
+ if (max3421_hcd->spi_thread &&
+ max3421_hcd->spi_thread->state != TASK_RUNNING)
+ wake_up_process(max3421_hcd->spi_thread);
+ if (!test_and_set_bit(ENABLE_IRQ, &max3421_hcd->todo))
+ disable_irq_nosync(spi->irq);
+ return IRQ_HANDLED;
+}
+
+#ifdef DEBUG
+
+static void
+dump_eps(struct usb_hcd *hcd)
+{
+ struct max3421_hcd *max3421_hcd = hcd_to_max3421(hcd);
+ struct max3421_ep *max3421_ep;
+ struct usb_host_endpoint *ep;
+ struct list_head *pos, *upos;
+ char ubuf[512], *dp, *end;
+ unsigned long flags;
+ struct urb *urb;
+ int epnum, ret;
+
+ spin_lock_irqsave(&max3421_hcd->lock, flags);
+ list_for_each(pos, &max3421_hcd->ep_list) {
+ max3421_ep = container_of(pos, struct max3421_ep, ep_list);
+ ep = max3421_ep->ep;
+
+ dp = ubuf;
+ end = dp + sizeof(ubuf);
+ *dp = '\0';
+ list_for_each(upos, &ep->urb_list) {
+ urb = container_of(upos, struct urb, urb_list);
+ ret = snprintf(dp, end - dp, " %p(%d.%s %d/%d)", urb,
+ usb_pipetype(urb->pipe),
+ usb_urb_dir_in(urb) ? "IN" : "OUT",
+ urb->actual_length,
+ urb->transfer_buffer_length);
+ if (ret < 0 || ret >= end - dp)
+ break; /* error or buffer full */
+ dp += ret;
+ }
+
+ epnum = usb_endpoint_num(&ep->desc);
+ pr_info("EP%0u %u lst %04u rtr %u nak %6u rxmt %u: %s\n",
+ epnum, max3421_ep->pkt_state, max3421_ep->last_active,
+ max3421_ep->retries, max3421_ep->naks,
+ max3421_ep->retransmit, ubuf);
+ }
+ spin_unlock_irqrestore(&max3421_hcd->lock, flags);
+}
+
+#endif /* DEBUG */
+
+/* Return zero if no work was performed, 1 otherwise. */
+static int
+max3421_handle_irqs(struct usb_hcd *hcd)
+{
+ struct max3421_hcd *max3421_hcd = hcd_to_max3421(hcd);
+ u32 chg, old_port_status;
+ unsigned long flags;
+ u8 hirq;
+
+ /*
+ * Read and ack pending interrupts (CPU must never
+ * clear SNDBAV directly and RCVDAV must be cleared by
+ * max3421_recv_data_available()!):
+ */
+ hirq = spi_rd8(hcd, MAX3421_REG_HIRQ);
+ hirq &= max3421_hcd->hien;
+ if (!hirq)
+ return 0;
+
+ spi_wr8(hcd, MAX3421_REG_HIRQ,
+ hirq & ~(BIT(MAX3421_HI_SNDBAV_BIT) |
+ BIT(MAX3421_HI_RCVDAV_BIT)));
+
+ if (hirq & BIT(MAX3421_HI_FRAME_BIT)) {
+ max3421_hcd->frame_number = ((max3421_hcd->frame_number + 1)
+ & USB_MAX_FRAME_NUMBER);
+ max3421_hcd->sched_pass = SCHED_PASS_PERIODIC;
+ }
+
+ if (hirq & BIT(MAX3421_HI_RCVDAV_BIT))
+ max3421_recv_data_available(hcd);
+
+ if (hirq & BIT(MAX3421_HI_HXFRDN_BIT))
+ max3421_host_transfer_done(hcd);
+
+ if (hirq & BIT(MAX3421_HI_CONDET_BIT))
+ max3421_detect_conn(hcd);
+
+ /*
+ * Now process interrupts that may affect HCD state
+ * other than the end-points:
+ */
+ spin_lock_irqsave(&max3421_hcd->lock, flags);
+
+ old_port_status = max3421_hcd->port_status;
+ if (hirq & BIT(MAX3421_HI_BUSEVENT_BIT)) {
+ if (max3421_hcd->port_status & USB_PORT_STAT_RESET) {
+ /* BUSEVENT due to completion of Bus Reset */
+ max3421_hcd->port_status &= ~USB_PORT_STAT_RESET;
+ max3421_hcd->port_status |= USB_PORT_STAT_ENABLE;
+ } else {
+ /* BUSEVENT due to completion of Bus Resume */
+ pr_info("%s: BUSEVENT Bus Resume Done\n", __func__);
+ }
+ }
+ if (hirq & BIT(MAX3421_HI_RWU_BIT))
+ pr_info("%s: RWU\n", __func__);
+ if (hirq & BIT(MAX3421_HI_SUSDN_BIT))
+ pr_info("%s: SUSDN\n", __func__);
+
+ chg = (old_port_status ^ max3421_hcd->port_status);
+ max3421_hcd->port_status |= chg << 16;
+
+ spin_unlock_irqrestore(&max3421_hcd->lock, flags);
+
+#ifdef DEBUG
+ {
+ static unsigned long last_time;
+ char sbuf[16 * 16], *dp, *end;
+ int i;
+
+ if (time_after(jiffies, last_time + 5*HZ)) {
+ dp = sbuf;
+ end = sbuf + sizeof(sbuf);
+ *dp = '\0';
+ for (i = 0; i < 16; ++i) {
+ int ret = snprintf(dp, end - dp, " %lu",
+ max3421_hcd->err_stat[i]);
+ if (ret < 0 || ret >= end - dp)
+ break; /* error or buffer full */
+ dp += ret;
+ }
+ pr_info("%s: hrsl_stats %s\n", __func__, sbuf);
+ memset(max3421_hcd->err_stat, 0,
+ sizeof(max3421_hcd->err_stat));
+ last_time = jiffies;
+
+ dump_eps(hcd);
+ }
+ }
+#endif
+ return 1;
+}
+
+static int
+max3421_reset_hcd(struct usb_hcd *hcd)
+{
+ struct spi_device *spi = to_spi_device(hcd->self.controller);
+ struct max3421_hcd *max3421_hcd = hcd_to_max3421(hcd);
+ int timeout;
+
+ /* perform a chip reset and wait for OSCIRQ signal to appear: */
+ spi_wr8(hcd, MAX3421_REG_USBCTL, BIT(MAX3421_USBCTL_CHIPRES_BIT));
+ /* clear reset: */
+ spi_wr8(hcd, MAX3421_REG_USBCTL, 0);
+ timeout = 1000;
+ while (1) {
+ if (spi_rd8(hcd, MAX3421_REG_USBIRQ)
+ & BIT(MAX3421_USBIRQ_OSCOKIRQ_BIT))
+ break;
+ if (--timeout < 0) {
+ dev_err(&spi->dev,
+ "timed out waiting for oscillator OK signal");
+ return 1;
+ }
+ cond_resched();
+ }
+
+ /*
+ * Turn on host mode, automatic generation of SOF packets, and
+ * enable pull-down registers on DM/DP:
+ */
+ max3421_hcd->mode = (BIT(MAX3421_MODE_HOST_BIT) |
+ BIT(MAX3421_MODE_SOFKAENAB_BIT) |
+ BIT(MAX3421_MODE_DMPULLDN_BIT) |
+ BIT(MAX3421_MODE_DPPULLDN_BIT));
+ spi_wr8(hcd, MAX3421_REG_MODE, max3421_hcd->mode);
+
+ /* reset frame-number: */
+ max3421_hcd->frame_number = USB_MAX_FRAME_NUMBER;
+ spi_wr8(hcd, MAX3421_REG_HCTL, BIT(MAX3421_HCTL_FRMRST_BIT));
+
+ /* sample the state of the D+ and D- lines */
+ spi_wr8(hcd, MAX3421_REG_HCTL, BIT(MAX3421_HCTL_SAMPLEBUS_BIT));
+ max3421_detect_conn(hcd);
+
+ /* enable frame, connection-detected, and bus-event interrupts: */
+ max3421_hcd->hien = (BIT(MAX3421_HI_FRAME_BIT) |
+ BIT(MAX3421_HI_CONDET_BIT) |
+ BIT(MAX3421_HI_BUSEVENT_BIT));
+ spi_wr8(hcd, MAX3421_REG_HIEN, max3421_hcd->hien);
+
+ /* enable interrupts: */
+ spi_wr8(hcd, MAX3421_REG_CPUCTL, BIT(MAX3421_CPUCTL_IE_BIT));
+ return 1;
+}
+
+static int
+max3421_urb_done(struct usb_hcd *hcd)
+{
+ struct max3421_hcd *max3421_hcd = hcd_to_max3421(hcd);
+ unsigned long flags;
+ struct urb *urb;
+ int status;
+
+ status = max3421_hcd->urb_done;
+ max3421_hcd->urb_done = 0;
+ if (status > 0)
+ status = 0;
+ urb = max3421_hcd->curr_urb;
+ if (urb) {
+ max3421_hcd->curr_urb = NULL;
+ spin_lock_irqsave(&max3421_hcd->lock, flags);
+ usb_hcd_unlink_urb_from_ep(hcd, urb);
+ spin_unlock_irqrestore(&max3421_hcd->lock, flags);
+
+ /* must be called without the HCD spinlock: */
+ usb_hcd_giveback_urb(hcd, urb, status);
+ }
+ return 1;
+}
+
+static int
+max3421_spi_thread(void *dev_id)
+{
+ struct usb_hcd *hcd = dev_id;
+ struct spi_device *spi = to_spi_device(hcd->self.controller);
+ struct max3421_hcd *max3421_hcd = hcd_to_max3421(hcd);
+ int i, i_worked = 1;
+
+ /* set full-duplex SPI mode, low-active interrupt pin: */
+ spi_wr8(hcd, MAX3421_REG_PINCTL,
+ (BIT(MAX3421_PINCTL_FDUPSPI_BIT) | /* full-duplex */
+ BIT(MAX3421_PINCTL_INTLEVEL_BIT))); /* low-active irq */
+
+ while (!kthread_should_stop()) {
+ max3421_hcd->rev = spi_rd8(hcd, MAX3421_REG_REVISION);
+ if (max3421_hcd->rev == 0x12 || max3421_hcd->rev == 0x13)
+ break;
+ dev_err(&spi->dev, "bad rev 0x%02x", max3421_hcd->rev);
+ msleep(10000);
+ }
+ dev_info(&spi->dev, "rev 0x%x, SPI clk %dHz, bpw %u, irq %d\n",
+ max3421_hcd->rev, spi->max_speed_hz, spi->bits_per_word,
+ spi->irq);
+
+ while (!kthread_should_stop()) {
+ if (!i_worked) {
+ /*
+ * We'll be waiting for wakeups from the hard
+ * interrupt handler, so now is a good time to
+ * sync our hien with the chip:
+ */
+ spi_wr8(hcd, MAX3421_REG_HIEN, max3421_hcd->hien);
+
+ set_current_state(TASK_INTERRUPTIBLE);
+ if (test_and_clear_bit(ENABLE_IRQ, &max3421_hcd->todo))
+ enable_irq(spi->irq);
+ schedule();
+ __set_current_state(TASK_RUNNING);
+ }
+
+ i_worked = 0;
+
+ if (max3421_hcd->urb_done)
+ i_worked |= max3421_urb_done(hcd);
+ else if (max3421_handle_irqs(hcd))
+ i_worked = 1;
+ else if (!max3421_hcd->curr_urb)
+ i_worked |= max3421_select_and_start_urb(hcd);
+
+ if (test_and_clear_bit(RESET_HCD, &max3421_hcd->todo))
+ /* reset the HCD: */
+ i_worked |= max3421_reset_hcd(hcd);
+ if (test_and_clear_bit(RESET_PORT, &max3421_hcd->todo)) {
+ /* perform a USB bus reset: */
+ spi_wr8(hcd, MAX3421_REG_HCTL,
+ BIT(MAX3421_HCTL_BUSRST_BIT));
+ i_worked = 1;
+ }
+ if (test_and_clear_bit(CHECK_UNLINK, &max3421_hcd->todo))
+ i_worked |= max3421_check_unlink(hcd);
+ if (test_and_clear_bit(IOPIN_UPDATE, &max3421_hcd->todo)) {
+ /*
+ * IOPINS1/IOPINS2 do not auto-increment, so we can't
+ * use spi_wr_buf().
+ */
+ for (i = 0; i < ARRAY_SIZE(max3421_hcd->iopins); ++i) {
+ u8 val = spi_rd8(hcd, MAX3421_REG_IOPINS1);
+
+ val = ((val & 0xf0) |
+ (max3421_hcd->iopins[i] & 0x0f));
+ spi_wr8(hcd, MAX3421_REG_IOPINS1 + i, val);
+ max3421_hcd->iopins[i] = val;
+ }
+ i_worked = 1;
+ }
+ }
+ set_current_state(TASK_RUNNING);
+ dev_info(&spi->dev, "SPI thread exiting");
+ return 0;
+}
+
+static int
+max3421_reset_port(struct usb_hcd *hcd)
+{
+ struct max3421_hcd *max3421_hcd = hcd_to_max3421(hcd);
+
+ max3421_hcd->port_status &= ~(USB_PORT_STAT_ENABLE |
+ USB_PORT_STAT_LOW_SPEED);
+ max3421_hcd->port_status |= USB_PORT_STAT_RESET;
+ set_bit(RESET_PORT, &max3421_hcd->todo);
+ wake_up_process(max3421_hcd->spi_thread);
+ return 0;
+}
+
+static int
+max3421_reset(struct usb_hcd *hcd)
+{
+ struct max3421_hcd *max3421_hcd = hcd_to_max3421(hcd);
+
+ hcd->self.sg_tablesize = 0;
+ hcd->speed = HCD_USB2;
+ hcd->self.root_hub->speed = USB_SPEED_FULL;
+ set_bit(RESET_HCD, &max3421_hcd->todo);
+ wake_up_process(max3421_hcd->spi_thread);
+ return 0;
+}
+
+static int
+max3421_start(struct usb_hcd *hcd)
+{
+ struct max3421_hcd *max3421_hcd = hcd_to_max3421(hcd);
+
+ spin_lock_init(&max3421_hcd->lock);
+ max3421_hcd->rh_state = MAX3421_RH_RUNNING;
+
+ INIT_LIST_HEAD(&max3421_hcd->ep_list);
+
+ hcd->power_budget = POWER_BUDGET;
+ hcd->state = HC_STATE_RUNNING;
+ hcd->uses_new_polling = 1;
+ return 0;
+}
+
+static void
+max3421_stop(struct usb_hcd *hcd)
+{
+}
+
+static int
+max3421_urb_enqueue(struct usb_hcd *hcd, struct urb *urb, gfp_t mem_flags)
+{
+ struct spi_device *spi = to_spi_device(hcd->self.controller);
+ struct max3421_hcd *max3421_hcd = hcd_to_max3421(hcd);
+ struct max3421_ep *max3421_ep;
+ unsigned long flags;
+ int retval;
+
+ switch (usb_pipetype(urb->pipe)) {
+ case PIPE_INTERRUPT:
+ case PIPE_ISOCHRONOUS:
+ if (urb->interval < 0) {
+ dev_err(&spi->dev,
+ "%s: interval=%d for intr-/iso-pipe; expected > 0\n",
+ __func__, urb->interval);
+ return -EINVAL;
+ }
+ default:
+ break;
+ }
+
+ spin_lock_irqsave(&max3421_hcd->lock, flags);
+
+ max3421_ep = urb->ep->hcpriv;
+ if (!max3421_ep) {
+ /* gets freed in max3421_endpoint_disable: */
+ max3421_ep = kzalloc(sizeof(struct max3421_ep), GFP_ATOMIC);
+ if (!max3421_ep) {
+ retval = -ENOMEM;
+ goto out;
+ }
+ max3421_ep->ep = urb->ep;
+ max3421_ep->last_active = max3421_hcd->frame_number;
+ urb->ep->hcpriv = max3421_ep;
+
+ list_add_tail(&max3421_ep->ep_list, &max3421_hcd->ep_list);
+ }
+
+ retval = usb_hcd_link_urb_to_ep(hcd, urb);
+ if (retval == 0) {
+ /* Since we added to the queue, restart scheduling: */
+ max3421_hcd->sched_pass = SCHED_PASS_PERIODIC;
+ wake_up_process(max3421_hcd->spi_thread);
+ }
+
+out:
+ spin_unlock_irqrestore(&max3421_hcd->lock, flags);
+ return retval;
+}
+
+static int
+max3421_urb_dequeue(struct usb_hcd *hcd, struct urb *urb, int status)
+{
+ struct max3421_hcd *max3421_hcd = hcd_to_max3421(hcd);
+ unsigned long flags;
+ int retval;
+
+ spin_lock_irqsave(&max3421_hcd->lock, flags);
+
+ /*
+ * This will set urb->unlinked which in turn causes the entry
+ * to be dropped at the next opportunity.
+ */
+ retval = usb_hcd_check_unlink_urb(hcd, urb, status);
+ if (retval == 0) {
+ set_bit(CHECK_UNLINK, &max3421_hcd->todo);
+ wake_up_process(max3421_hcd->spi_thread);
+ }
+ spin_unlock_irqrestore(&max3421_hcd->lock, flags);
+ return retval;
+}
+
+static void
+max3421_endpoint_disable(struct usb_hcd *hcd, struct usb_host_endpoint *ep)
+{
+ struct max3421_hcd *max3421_hcd = hcd_to_max3421(hcd);
+ unsigned long flags;
+
+ spin_lock_irqsave(&max3421_hcd->lock, flags);
+
+ if (ep->hcpriv) {
+ struct max3421_ep *max3421_ep = ep->hcpriv;
+
+ /* remove myself from the ep_list: */
+ if (!list_empty(&max3421_ep->ep_list))
+ list_del(&max3421_ep->ep_list);
+ kfree(max3421_ep);
+ ep->hcpriv = NULL;
+ }
+
+ spin_unlock_irqrestore(&max3421_hcd->lock, flags);
+}
+
+static int
+max3421_get_frame_number(struct usb_hcd *hcd)
+{
+ struct max3421_hcd *max3421_hcd = hcd_to_max3421(hcd);
+ return max3421_hcd->frame_number;
+}
+
+/*
+ * Should return a non-zero value when any port is undergoing a resume
+ * transition while the root hub is suspended.
+ */
+static int
+max3421_hub_status_data(struct usb_hcd *hcd, char *buf)
+{
+ struct max3421_hcd *max3421_hcd = hcd_to_max3421(hcd);
+ unsigned long flags;
+ int retval = 0;
+
+ spin_lock_irqsave(&max3421_hcd->lock, flags);
+ if (!HCD_HW_ACCESSIBLE(hcd))
+ goto done;
+
+ *buf = 0;
+ if ((max3421_hcd->port_status & PORT_C_MASK) != 0) {
+ *buf = (1 << 1); /* a hub over-current condition exists */
+ dev_dbg(hcd->self.controller,
+ "port status 0x%08x has changes\n",
+ max3421_hcd->port_status);
+ retval = 1;
+ if (max3421_hcd->rh_state == MAX3421_RH_SUSPENDED)
+ usb_hcd_resume_root_hub(hcd);
+ }
+done:
+ spin_unlock_irqrestore(&max3421_hcd->lock, flags);
+ return retval;
+}
+
+static inline void
+hub_descriptor(struct usb_hub_descriptor *desc)
+{
+ memset(desc, 0, sizeof(*desc));
+ /*
+ * See Table 11-13: Hub Descriptor in USB 2.0 spec.
+ */
+ desc->bDescriptorType = USB_DT_HUB; /* hub descriptor */
+ desc->bDescLength = 9;
+ desc->wHubCharacteristics = cpu_to_le16(HUB_CHAR_INDV_PORT_LPSM |
+ HUB_CHAR_COMMON_OCPM);
+ desc->bNbrPorts = 1;
+}
+
+/*
+ * Set the MAX3421E general-purpose output with number PIN_NUMBER to
+ * VALUE (0 or 1). PIN_NUMBER may be in the range from 1-8. For
+ * any other value, this function acts as a no-op.
+ */
+static void
+max3421_gpout_set_value(struct usb_hcd *hcd, u8 pin_number, u8 value)
+{
+ struct max3421_hcd *max3421_hcd = hcd_to_max3421(hcd);
+ u8 mask, idx;
+
+ --pin_number;
+ if (pin_number > 7)
+ return;
+
+ mask = 1u << pin_number;
+ idx = pin_number / 4;
+
+ if (value)
+ max3421_hcd->iopins[idx] |= mask;
+ else
+ max3421_hcd->iopins[idx] &= ~mask;
+ set_bit(IOPIN_UPDATE, &max3421_hcd->todo);
+ wake_up_process(max3421_hcd->spi_thread);
+}
+
+static int
+max3421_hub_control(struct usb_hcd *hcd, u16 type_req, u16 value, u16 index,
+ char *buf, u16 length)
+{
+ struct spi_device *spi = to_spi_device(hcd->self.controller);
+ struct max3421_hcd *max3421_hcd = hcd_to_max3421(hcd);
+ struct max3421_hcd_platform_data *pdata;
+ unsigned long flags;
+ int retval = 0;
+
+ spin_lock_irqsave(&max3421_hcd->lock, flags);
+
+ pdata = spi->dev.platform_data;
+
+ switch (type_req) {
+ case ClearHubFeature:
+ break;
+ case ClearPortFeature:
+ switch (value) {
+ case USB_PORT_FEAT_SUSPEND:
+ break;
+ case USB_PORT_FEAT_POWER:
+ dev_dbg(hcd->self.controller, "power-off\n");
+ max3421_gpout_set_value(hcd, pdata->vbus_gpout,
+ !pdata->vbus_active_level);
+ /* FALLS THROUGH */
+ default:
+ max3421_hcd->port_status &= ~(1 << value);
+ }
+ break;
+ case GetHubDescriptor:
+ hub_descriptor((struct usb_hub_descriptor *) buf);
+ break;
+
+ case DeviceRequest | USB_REQ_GET_DESCRIPTOR:
+ case GetPortErrorCount:
+ case SetHubDepth:
+ /* USB3 only */
+ goto error;
+
+ case GetHubStatus:
+ *(__le32 *) buf = cpu_to_le32(0);
+ break;
+
+ case GetPortStatus:
+ if (index != 1) {
+ retval = -EPIPE;
+ goto error;
+ }
+ ((__le16 *) buf)[0] = cpu_to_le16(max3421_hcd->port_status);
+ ((__le16 *) buf)[1] =
+ cpu_to_le16(max3421_hcd->port_status >> 16);
+ break;
+
+ case SetHubFeature:
+ retval = -EPIPE;
+ break;
+
+ case SetPortFeature:
+ switch (value) {
+ case USB_PORT_FEAT_LINK_STATE:
+ case USB_PORT_FEAT_U1_TIMEOUT:
+ case USB_PORT_FEAT_U2_TIMEOUT:
+ case USB_PORT_FEAT_BH_PORT_RESET:
+ goto error;
+ case USB_PORT_FEAT_SUSPEND:
+ if (max3421_hcd->active)
+ max3421_hcd->port_status |=
+ USB_PORT_STAT_SUSPEND;
+ break;
+ case USB_PORT_FEAT_POWER:
+ dev_dbg(hcd->self.controller, "power-on\n");
+ max3421_hcd->port_status |= USB_PORT_STAT_POWER;
+ max3421_gpout_set_value(hcd, pdata->vbus_gpout,
+ pdata->vbus_active_level);
+ break;
+ case USB_PORT_FEAT_RESET:
+ max3421_reset_port(hcd);
+ /* FALLS THROUGH */
+ default:
+ if ((max3421_hcd->port_status & USB_PORT_STAT_POWER)
+ != 0)
+ max3421_hcd->port_status |= (1 << value);
+ }
+ break;
+
+ default:
+ dev_dbg(hcd->self.controller,
+ "hub control req%04x v%04x i%04x l%d\n",
+ type_req, value, index, length);
+error: /* "protocol stall" on error */
+ retval = -EPIPE;
+ }
+
+ spin_unlock_irqrestore(&max3421_hcd->lock, flags);
+ return retval;
+}
+
+static int
+max3421_bus_suspend(struct usb_hcd *hcd)
+{
+ return -1;
+}
+
+static int
+max3421_bus_resume(struct usb_hcd *hcd)
+{
+ return -1;
+}
+
+/*
+ * The SPI driver already takes care of DMA-mapping/unmapping, so no
+ * reason to do it twice.
+ */
+static int
+max3421_map_urb_for_dma(struct usb_hcd *hcd, struct urb *urb, gfp_t mem_flags)
+{
+ return 0;
+}
+
+static void
+max3421_unmap_urb_for_dma(struct usb_hcd *hcd, struct urb *urb)
+{
+}
+
+static struct hc_driver max3421_hcd_desc = {
+ .description = "max3421",
+ .product_desc = DRIVER_DESC,
+ .hcd_priv_size = sizeof(struct max3421_hcd),
+ .flags = HCD_USB11,
+ .reset = max3421_reset,
+ .start = max3421_start,
+ .stop = max3421_stop,
+ .get_frame_number = max3421_get_frame_number,
+ .urb_enqueue = max3421_urb_enqueue,
+ .urb_dequeue = max3421_urb_dequeue,
+ .map_urb_for_dma = max3421_map_urb_for_dma,
+ .unmap_urb_for_dma = max3421_unmap_urb_for_dma,
+ .endpoint_disable = max3421_endpoint_disable,
+ .hub_status_data = max3421_hub_status_data,
+ .hub_control = max3421_hub_control,
+ .bus_suspend = max3421_bus_suspend,
+ .bus_resume = max3421_bus_resume,
+};
+
+static int
+max3421_probe(struct spi_device *spi)
+{
+ struct max3421_hcd *max3421_hcd;
+ struct usb_hcd *hcd = NULL;
+ int retval = -ENOMEM;
+
+ if (spi_setup(spi) < 0) {
+ dev_err(&spi->dev, "Unable to setup SPI bus");
+ return -EFAULT;
+ }
+
+ hcd = usb_create_hcd(&max3421_hcd_desc, &spi->dev,
+ dev_name(&spi->dev));
+ if (!hcd) {
+ dev_err(&spi->dev, "failed to create HCD structure\n");
+ goto error;
+ }
+ set_bit(HCD_FLAG_POLL_RH, &hcd->flags);
+ max3421_hcd = hcd_to_max3421(hcd);
+ max3421_hcd->next = max3421_hcd_list;
+ max3421_hcd_list = max3421_hcd;
+ INIT_LIST_HEAD(&max3421_hcd->ep_list);
+
+ max3421_hcd->tx = kmalloc(sizeof(*max3421_hcd->tx), GFP_KERNEL);
+ if (!max3421_hcd->tx) {
+ dev_err(&spi->dev, "failed to kmalloc tx buffer\n");
+ goto error;
+ }
+ max3421_hcd->rx = kmalloc(sizeof(*max3421_hcd->rx), GFP_KERNEL);
+ if (!max3421_hcd->rx) {
+ dev_err(&spi->dev, "failed to kmalloc rx buffer\n");
+ goto error;
+ }
+
+ max3421_hcd->spi_thread = kthread_run(max3421_spi_thread, hcd,
+ "max3421_spi_thread");
+ if (max3421_hcd->spi_thread == ERR_PTR(-ENOMEM)) {
+ dev_err(&spi->dev,
+ "failed to create SPI thread (out of memory)\n");
+ goto error;
+ }
+
+ retval = usb_add_hcd(hcd, 0, 0);
+ if (retval) {
+ dev_err(&spi->dev, "failed to add HCD\n");
+ goto error;
+ }
+
+ retval = request_irq(spi->irq, max3421_irq_handler,
+ IRQF_TRIGGER_LOW, "max3421", hcd);
+ if (retval < 0) {
+ dev_err(&spi->dev, "failed to request irq %d\n", spi->irq);
+ goto error;
+ }
+ return 0;
+
+error:
+ if (hcd) {
+ kfree(max3421_hcd->tx);
+ kfree(max3421_hcd->rx);
+ if (max3421_hcd->spi_thread)
+ kthread_stop(max3421_hcd->spi_thread);
+ usb_put_hcd(hcd);
+ }
+ return retval;
+}
+
+static int
+max3421_remove(struct spi_device *spi)
+{
+ struct max3421_hcd *max3421_hcd = NULL, **prev;
+ struct usb_hcd *hcd = NULL;
+ unsigned long flags;
+
+ for (prev = &max3421_hcd_list; *prev; prev = &(*prev)->next) {
+ max3421_hcd = *prev;
+ hcd = max3421_to_hcd(max3421_hcd);
+ if (hcd->self.controller == &spi->dev)
+ break;
+ }
+ if (!max3421_hcd) {
+ dev_err(&spi->dev, "no MAX3421 HCD found for SPI device %p\n",
+ spi);
+ return -ENODEV;
+ }
+
+ usb_remove_hcd(hcd);
+
+ spin_lock_irqsave(&max3421_hcd->lock, flags);
+
+ kthread_stop(max3421_hcd->spi_thread);
+ *prev = max3421_hcd->next;
+
+ spin_unlock_irqrestore(&max3421_hcd->lock, flags);
+
+ free_irq(spi->irq, hcd);
+
+ usb_put_hcd(hcd);
+ return 0;
+}
+
+static struct spi_driver max3421_driver = {
+ .probe = max3421_probe,
+ .remove = max3421_remove,
+ .driver = {
+ .name = "max3421-hcd",
+ },
+};
+
+module_spi_driver(max3421_driver);
+
+MODULE_DESCRIPTION(DRIVER_DESC);
+MODULE_AUTHOR("David Mosberger <davidm@egauge.net>");
+MODULE_LICENSE("GPL");