// SPDX-License-Identifier: GPL-2.0
/*
* MAX3421 Host Controller driver for USB.
*
* Author: David Mosberger-Tang <[email protected]>
*
* (C) Copyright 2014 David Mosberger-Tang <[email protected]>
*
* MAX3421 is a chip implementing a USB 2.0 Full-/Low-Speed host
* controller on a SPI bus.
*
* Based on:
* o MAX3421E datasheet
* https://datasheets.maximintegrated.com/en/ds/MAX3421E.pdf
* o MAX3421E Programming Guide
* https://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/of.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 */
#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)
#define MAX3421_GPOUT_COUNT 8
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;
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;
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 */
};
#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 https://www.beyondlogic.org/usbnutshell/usb4.shtml#Control for a
* reasonable overview of how control transfers use 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 rcvtog, sndtog;
u8 hctl;
/* 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));
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.
*/
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);
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;
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;
} 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);
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 max3421_ep *max3421_ep;
struct usb_host_endpoint *ep;
struct urb *urb, *next;
unsigned long flags;
int retval = 0;
spin_lock_irqsave(&max3421_hcd->lock, flags);
list_for_each_entry(max3421_ep, &max3421_hcd->ep_list, ep_list) {
ep = max3421_ep->ep;
list_for_each_entry_safe(urb, next, &ep->urb_list, 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));
}
fallthrough;
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.
*/
max3421_next_transfer(hcd, 1);
switch_sndfifo = 0;
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);
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);
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)
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;
char ubuf[512], *dp, *end;
unsigned long flags;
struct urb *urb;
int epnum, ret;
spin_lock_irqsave(&max3421_hcd->lock, flags);
list_for_each_entry(max3421_ep, &max3421_hcd->ep_list, ep_list) {
ep = max3421_ep->ep;
dp = ubuf;
end = dp + sizeof(ubuf);
*dp = '\0';
list_for_each_entry(urb, &ep->urb_list, urb_list) {
ret = scnprintf(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 == end - dp - 1)
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 = scnprintf(dp, end - dp, " %lu",
max3421_hcd->err_stat[i]);
if (ret == end - dp - 1)
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) {
/* save the old end-points toggles: */
u8 hrsl = spi_rd8(hcd, MAX3421_REG_HRSL);
int rcvtog = (hrsl >> MAX3421_HRSL_RCVTOGRD_BIT) & 1;
int sndtog = (hrsl >> MAX3421_HRSL_SNDTOGRD_BIT) & 1;
int epnum = usb_endpoint_num(&urb->ep->desc);
/* no locking: HCD (i.e., we) own toggles, don't we? */
usb_settoggle(urb->dev, epnum, 0, rcvtog);
usb_settoggle(urb->dev, epnum, 1, sndtog);
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 + i);
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;
}
break;
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 >= MAX3421_GPOUT_COUNT)
return;
mask = 1u << (pin_number % 4);
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;
pdata = spi->dev.platform_data;
spin_lock_irqsave(&max3421_hcd->lock, flags);
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);
fallthrough;
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);
fallthrough;
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;
}
static const 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,
.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_of_vbus_en_pin(struct device *dev, struct max3421_hcd_platform_data *pdata)
{
int retval;
uint32_t value[2];
if (!pdata)
return -EINVAL;
retval = of_property_read_u32_array(dev->of_node, "maxim,vbus-en-pin", value, 2);
if (retval) {
dev_err(dev, "device tree node property 'maxim,vbus-en-pin' is missing\n");
return retval;
}
dev_info(dev, "property 'maxim,vbus-en-pin' value is <%d %d>\n", value[0], value[1]);
pdata->vbus_gpout = value[0];
pdata->vbus_active_level = value[1];
return 0;
}
static int
max3421_probe(struct spi_device *spi)
{
struct device *dev = &spi->dev;
struct max3421_hcd *max3421_hcd;
struct usb_hcd *hcd = NULL;
struct max3421_hcd_platform_data *pdata = NULL;
int retval;
if (spi_setup(spi) < 0) {
dev_err(&spi->dev, "Unable to setup SPI bus");
return -EFAULT;
}
if (!spi->irq) {
dev_err(dev, "Failed to get SPI IRQ");
return -EFAULT;
}
if (IS_ENABLED(CONFIG_OF) && dev->of_node) {
pdata = devm_kzalloc(&spi->dev, sizeof(*pdata), GFP_KERNEL);
if (!pdata) {
retval = -ENOMEM;
goto error;
}
retval = max3421_of_vbus_en_pin(dev, pdata);
if (retval)
goto error;
spi->dev.platform_data = pdata;
}
pdata = spi->dev.platform_data;
if (!pdata) {
dev_err(&spi->dev, "driver configuration data is not provided\n");
retval = -EFAULT;
goto error;
}
if (pdata->vbus_active_level > 1) {
dev_err(&spi->dev, "vbus active level value %d is out of range (0/1)\n", pdata->vbus_active_level);
retval = -EINVAL;
goto error;
}
if (pdata->vbus_gpout < 1 || pdata->vbus_gpout > MAX3421_GPOUT_COUNT) {
dev_err(&spi->dev, "vbus gpout value %d is out of range (1..8)\n", pdata->vbus_gpout);
retval = -EINVAL;
goto error;
}
retval = -ENOMEM;
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);
INIT_LIST_HEAD(&max3421_hcd->ep_list);
spi_set_drvdata(spi, max3421_hcd);
max3421_hcd->tx = kmalloc(sizeof(*max3421_hcd->tx), GFP_KERNEL);
if (!max3421_hcd->tx)
goto error;
max3421_hcd->rx = kmalloc(sizeof(*max3421_hcd->rx), GFP_KERNEL);
if (!max3421_hcd->rx)
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 (IS_ENABLED(CONFIG_OF) && dev->of_node && pdata) {
devm_kfree(&spi->dev, pdata);
spi->dev.platform_data = NULL;
}
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 void
max3421_remove(struct spi_device *spi)
{
struct max3421_hcd *max3421_hcd;
struct usb_hcd *hcd;
unsigned long flags;
max3421_hcd = spi_get_drvdata(spi);
hcd = max3421_to_hcd(max3421_hcd);
usb_remove_hcd(hcd);
spin_lock_irqsave(&max3421_hcd->lock, flags);
kthread_stop(max3421_hcd->spi_thread);
spin_unlock_irqrestore(&max3421_hcd->lock, flags);
free_irq(spi->irq, hcd);
usb_put_hcd(hcd);
}
static const struct of_device_id max3421_of_match_table[] = {
{ .compatible = "maxim,max3421", },
{},
};
MODULE_DEVICE_TABLE(of, max3421_of_match_table);
static struct spi_driver max3421_driver = {
.probe = max3421_probe,
.remove = max3421_remove,
.driver = {
.name = "max3421-hcd",
.of_match_table = max3421_of_match_table,
},
};
module_spi_driver(max3421_driver);
MODULE_DESCRIPTION(DRIVER_DESC);
MODULE_AUTHOR("David Mosberger <[email protected]>");
MODULE_LICENSE("GPL");
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