linux/drivers/tty/serial/ifx6x60.c
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   1/****************************************************************************
   2 *
   3 * Driver for the IFX 6x60 spi modem.
   4 *
   5 * Copyright (C) 2008 Option International
   6 * Copyright (C) 2008 Filip Aben <f.aben@option.com>
   7 *                    Denis Joseph Barrow <d.barow@option.com>
   8 *                    Jan Dumon <j.dumon@option.com>
   9 *
  10 * Copyright (C) 2009, 2010 Intel Corp
  11 * Russ Gorby <russ.gorby@intel.com>
  12 *
  13 * This program is free software; you can redistribute it and/or modify
  14 * it under the terms of the GNU General Public License version 2 as
  15 * published by the Free Software Foundation.
  16 *
  17 * This program is distributed in the hope that it will be useful,
  18 * but WITHOUT ANY WARRANTY; without even the implied warranty of
  19 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  20 * GNU General Public License for more details.
  21 *
  22 * You should have received a copy of the GNU General Public License
  23 * along with this program; if not, write to the Free Software
  24 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301,
  25 * USA
  26 *
  27 * Driver modified by Intel from Option gtm501l_spi.c
  28 *
  29 * Notes
  30 * o    The driver currently assumes a single device only. If you need to
  31 *      change this then look for saved_ifx_dev and add a device lookup
  32 * o    The driver is intended to be big-endian safe but has never been
  33 *      tested that way (no suitable hardware). There are a couple of FIXME
  34 *      notes by areas that may need addressing
  35 * o    Some of the GPIO naming/setup assumptions may need revisiting if
  36 *      you need to use this driver for another platform.
  37 *
  38 *****************************************************************************/
  39#include <linux/dma-mapping.h>
  40#include <linux/module.h>
  41#include <linux/termios.h>
  42#include <linux/tty.h>
  43#include <linux/device.h>
  44#include <linux/spi/spi.h>
  45#include <linux/kfifo.h>
  46#include <linux/tty_flip.h>
  47#include <linux/timer.h>
  48#include <linux/serial.h>
  49#include <linux/interrupt.h>
  50#include <linux/irq.h>
  51#include <linux/rfkill.h>
  52#include <linux/fs.h>
  53#include <linux/ip.h>
  54#include <linux/dmapool.h>
  55#include <linux/gpio.h>
  56#include <linux/sched.h>
  57#include <linux/time.h>
  58#include <linux/wait.h>
  59#include <linux/pm.h>
  60#include <linux/pm_runtime.h>
  61#include <linux/spi/ifx_modem.h>
  62#include <linux/delay.h>
  63#include <linux/reboot.h>
  64
  65#include "ifx6x60.h"
  66
  67#define IFX_SPI_MORE_MASK               0x10
  68#define IFX_SPI_MORE_BIT                4       /* bit position in u8 */
  69#define IFX_SPI_CTS_BIT                 6       /* bit position in u8 */
  70#define IFX_SPI_MODE                    SPI_MODE_1
  71#define IFX_SPI_TTY_ID                  0
  72#define IFX_SPI_TIMEOUT_SEC             2
  73#define IFX_SPI_HEADER_0                (-1)
  74#define IFX_SPI_HEADER_F                (-2)
  75
  76#define PO_POST_DELAY           200
  77#define IFX_MDM_RST_PMU 4
  78
  79/* forward reference */
  80static void ifx_spi_handle_srdy(struct ifx_spi_device *ifx_dev);
  81static int ifx_modem_reboot_callback(struct notifier_block *nfb,
  82                                unsigned long event, void *data);
  83static int ifx_modem_power_off(struct ifx_spi_device *ifx_dev);
  84
  85/* local variables */
  86static int spi_bpw = 16;                /* 8, 16 or 32 bit word length */
  87static struct tty_driver *tty_drv;
  88static struct ifx_spi_device *saved_ifx_dev;
  89static struct lock_class_key ifx_spi_key;
  90
  91static struct notifier_block ifx_modem_reboot_notifier_block = {
  92        .notifier_call = ifx_modem_reboot_callback,
  93};
  94
  95static int ifx_modem_power_off(struct ifx_spi_device *ifx_dev)
  96{
  97        gpio_set_value(IFX_MDM_RST_PMU, 1);
  98        msleep(PO_POST_DELAY);
  99
 100        return 0;
 101}
 102
 103static int ifx_modem_reboot_callback(struct notifier_block *nfb,
 104                                 unsigned long event, void *data)
 105{
 106        if (saved_ifx_dev)
 107                ifx_modem_power_off(saved_ifx_dev);
 108        else
 109                pr_warn("no ifx modem active;\n");
 110
 111        return NOTIFY_OK;
 112}
 113
 114/* GPIO/GPE settings */
 115
 116/**
 117 *      mrdy_set_high           -       set MRDY GPIO
 118 *      @ifx: device we are controlling
 119 *
 120 */
 121static inline void mrdy_set_high(struct ifx_spi_device *ifx)
 122{
 123        gpio_set_value(ifx->gpio.mrdy, 1);
 124}
 125
 126/**
 127 *      mrdy_set_low            -       clear MRDY GPIO
 128 *      @ifx: device we are controlling
 129 *
 130 */
 131static inline void mrdy_set_low(struct ifx_spi_device *ifx)
 132{
 133        gpio_set_value(ifx->gpio.mrdy, 0);
 134}
 135
 136/**
 137 *      ifx_spi_power_state_set
 138 *      @ifx_dev: our SPI device
 139 *      @val: bits to set
 140 *
 141 *      Set bit in power status and signal power system if status becomes non-0
 142 */
 143static void
 144ifx_spi_power_state_set(struct ifx_spi_device *ifx_dev, unsigned char val)
 145{
 146        unsigned long flags;
 147
 148        spin_lock_irqsave(&ifx_dev->power_lock, flags);
 149
 150        /*
 151         * if power status is already non-0, just update, else
 152         * tell power system
 153         */
 154        if (!ifx_dev->power_status)
 155                pm_runtime_get(&ifx_dev->spi_dev->dev);
 156        ifx_dev->power_status |= val;
 157
 158        spin_unlock_irqrestore(&ifx_dev->power_lock, flags);
 159}
 160
 161/**
 162 *      ifx_spi_power_state_clear       -       clear power bit
 163 *      @ifx_dev: our SPI device
 164 *      @val: bits to clear
 165 *
 166 *      clear bit in power status and signal power system if status becomes 0
 167 */
 168static void
 169ifx_spi_power_state_clear(struct ifx_spi_device *ifx_dev, unsigned char val)
 170{
 171        unsigned long flags;
 172
 173        spin_lock_irqsave(&ifx_dev->power_lock, flags);
 174
 175        if (ifx_dev->power_status) {
 176                ifx_dev->power_status &= ~val;
 177                if (!ifx_dev->power_status)
 178                        pm_runtime_put(&ifx_dev->spi_dev->dev);
 179        }
 180
 181        spin_unlock_irqrestore(&ifx_dev->power_lock, flags);
 182}
 183
 184/**
 185 *      swap_buf_8
 186 *      @buf: our buffer
 187 *      @len : number of bytes (not words) in the buffer
 188 *      @end: end of buffer
 189 *
 190 *      Swap the contents of a buffer into big endian format
 191 */
 192static inline void swap_buf_8(unsigned char *buf, int len, void *end)
 193{
 194        /* don't swap buffer if SPI word width is 8 bits */
 195        return;
 196}
 197
 198/**
 199 *      swap_buf_16
 200 *      @buf: our buffer
 201 *      @len : number of bytes (not words) in the buffer
 202 *      @end: end of buffer
 203 *
 204 *      Swap the contents of a buffer into big endian format
 205 */
 206static inline void swap_buf_16(unsigned char *buf, int len, void *end)
 207{
 208        int n;
 209
 210        u16 *buf_16 = (u16 *)buf;
 211        len = ((len + 1) >> 1);
 212        if ((void *)&buf_16[len] > end) {
 213                pr_err("swap_buf_16: swap exceeds boundary (%p > %p)!",
 214                       &buf_16[len], end);
 215                return;
 216        }
 217        for (n = 0; n < len; n++) {
 218                *buf_16 = cpu_to_be16(*buf_16);
 219                buf_16++;
 220        }
 221}
 222
 223/**
 224 *      swap_buf_32
 225 *      @buf: our buffer
 226 *      @len : number of bytes (not words) in the buffer
 227 *      @end: end of buffer
 228 *
 229 *      Swap the contents of a buffer into big endian format
 230 */
 231static inline void swap_buf_32(unsigned char *buf, int len, void *end)
 232{
 233        int n;
 234
 235        u32 *buf_32 = (u32 *)buf;
 236        len = (len + 3) >> 2;
 237
 238        if ((void *)&buf_32[len] > end) {
 239                pr_err("swap_buf_32: swap exceeds boundary (%p > %p)!\n",
 240                       &buf_32[len], end);
 241                return;
 242        }
 243        for (n = 0; n < len; n++) {
 244                *buf_32 = cpu_to_be32(*buf_32);
 245                buf_32++;
 246        }
 247}
 248
 249/**
 250 *      mrdy_assert             -       assert MRDY line
 251 *      @ifx_dev: our SPI device
 252 *
 253 *      Assert mrdy and set timer to wait for SRDY interrupt, if SRDY is low
 254 *      now.
 255 *
 256 *      FIXME: Can SRDY even go high as we are running this code ?
 257 */
 258static void mrdy_assert(struct ifx_spi_device *ifx_dev)
 259{
 260        int val = gpio_get_value(ifx_dev->gpio.srdy);
 261        if (!val) {
 262                if (!test_and_set_bit(IFX_SPI_STATE_TIMER_PENDING,
 263                                      &ifx_dev->flags)) {
 264                        mod_timer(&ifx_dev->spi_timer,jiffies + IFX_SPI_TIMEOUT_SEC*HZ);
 265
 266                }
 267        }
 268        ifx_spi_power_state_set(ifx_dev, IFX_SPI_POWER_DATA_PENDING);
 269        mrdy_set_high(ifx_dev);
 270}
 271
 272/**
 273 *      ifx_spi_timeout         -       SPI timeout
 274 *      @arg: our SPI device
 275 *
 276 *      The SPI has timed out: hang up the tty. Users will then see a hangup
 277 *      and error events.
 278 */
 279static void ifx_spi_timeout(unsigned long arg)
 280{
 281        struct ifx_spi_device *ifx_dev = (struct ifx_spi_device *)arg;
 282
 283        dev_warn(&ifx_dev->spi_dev->dev, "*** SPI Timeout ***");
 284        tty_port_tty_hangup(&ifx_dev->tty_port, false);
 285        mrdy_set_low(ifx_dev);
 286        clear_bit(IFX_SPI_STATE_TIMER_PENDING, &ifx_dev->flags);
 287}
 288
 289/* char/tty operations */
 290
 291/**
 292 *      ifx_spi_tiocmget        -       get modem lines
 293 *      @tty: our tty device
 294 *      @filp: file handle issuing the request
 295 *
 296 *      Map the signal state into Linux modem flags and report the value
 297 *      in Linux terms
 298 */
 299static int ifx_spi_tiocmget(struct tty_struct *tty)
 300{
 301        unsigned int value;
 302        struct ifx_spi_device *ifx_dev = tty->driver_data;
 303
 304        value =
 305        (test_bit(IFX_SPI_RTS, &ifx_dev->signal_state) ? TIOCM_RTS : 0) |
 306        (test_bit(IFX_SPI_DTR, &ifx_dev->signal_state) ? TIOCM_DTR : 0) |
 307        (test_bit(IFX_SPI_CTS, &ifx_dev->signal_state) ? TIOCM_CTS : 0) |
 308        (test_bit(IFX_SPI_DSR, &ifx_dev->signal_state) ? TIOCM_DSR : 0) |
 309        (test_bit(IFX_SPI_DCD, &ifx_dev->signal_state) ? TIOCM_CAR : 0) |
 310        (test_bit(IFX_SPI_RI, &ifx_dev->signal_state) ? TIOCM_RNG : 0);
 311        return value;
 312}
 313
 314/**
 315 *      ifx_spi_tiocmset        -       set modem bits
 316 *      @tty: the tty structure
 317 *      @set: bits to set
 318 *      @clear: bits to clear
 319 *
 320 *      The IFX6x60 only supports DTR and RTS. Set them accordingly
 321 *      and flag that an update to the modem is needed.
 322 *
 323 *      FIXME: do we need to kick the tranfers when we do this ?
 324 */
 325static int ifx_spi_tiocmset(struct tty_struct *tty,
 326                            unsigned int set, unsigned int clear)
 327{
 328        struct ifx_spi_device *ifx_dev = tty->driver_data;
 329
 330        if (set & TIOCM_RTS)
 331                set_bit(IFX_SPI_RTS, &ifx_dev->signal_state);
 332        if (set & TIOCM_DTR)
 333                set_bit(IFX_SPI_DTR, &ifx_dev->signal_state);
 334        if (clear & TIOCM_RTS)
 335                clear_bit(IFX_SPI_RTS, &ifx_dev->signal_state);
 336        if (clear & TIOCM_DTR)
 337                clear_bit(IFX_SPI_DTR, &ifx_dev->signal_state);
 338
 339        set_bit(IFX_SPI_UPDATE, &ifx_dev->signal_state);
 340        return 0;
 341}
 342
 343/**
 344 *      ifx_spi_open    -       called on tty open
 345 *      @tty: our tty device
 346 *      @filp: file handle being associated with the tty
 347 *
 348 *      Open the tty interface. We let the tty_port layer do all the work
 349 *      for us.
 350 *
 351 *      FIXME: Remove single device assumption and saved_ifx_dev
 352 */
 353static int ifx_spi_open(struct tty_struct *tty, struct file *filp)
 354{
 355        return tty_port_open(&saved_ifx_dev->tty_port, tty, filp);
 356}
 357
 358/**
 359 *      ifx_spi_close   -       called when our tty closes
 360 *      @tty: the tty being closed
 361 *      @filp: the file handle being closed
 362 *
 363 *      Perform the close of the tty. We use the tty_port layer to do all
 364 *      our hard work.
 365 */
 366static void ifx_spi_close(struct tty_struct *tty, struct file *filp)
 367{
 368        struct ifx_spi_device *ifx_dev = tty->driver_data;
 369        tty_port_close(&ifx_dev->tty_port, tty, filp);
 370        /* FIXME: should we do an ifx_spi_reset here ? */
 371}
 372
 373/**
 374 *      ifx_decode_spi_header   -       decode received header
 375 *      @buffer: the received data
 376 *      @length: decoded length
 377 *      @more: decoded more flag
 378 *      @received_cts: status of cts we received
 379 *
 380 *      Note how received_cts is handled -- if header is all F it is left
 381 *      the same as it was, if header is all 0 it is set to 0 otherwise it is
 382 *      taken from the incoming header.
 383 *
 384 *      FIXME: endianness
 385 */
 386static int ifx_spi_decode_spi_header(unsigned char *buffer, int *length,
 387                        unsigned char *more, unsigned char *received_cts)
 388{
 389        u16 h1;
 390        u16 h2;
 391        u16 *in_buffer = (u16 *)buffer;
 392
 393        h1 = *in_buffer;
 394        h2 = *(in_buffer+1);
 395
 396        if (h1 == 0 && h2 == 0) {
 397                *received_cts = 0;
 398                return IFX_SPI_HEADER_0;
 399        } else if (h1 == 0xffff && h2 == 0xffff) {
 400                /* spi_slave_cts remains as it was */
 401                return IFX_SPI_HEADER_F;
 402        }
 403
 404        *length = h1 & 0xfff;   /* upper bits of byte are flags */
 405        *more = (buffer[1] >> IFX_SPI_MORE_BIT) & 1;
 406        *received_cts = (buffer[3] >> IFX_SPI_CTS_BIT) & 1;
 407        return 0;
 408}
 409
 410/**
 411 *      ifx_setup_spi_header    -       set header fields
 412 *      @txbuffer: pointer to start of SPI buffer
 413 *      @tx_count: bytes
 414 *      @more: indicate if more to follow
 415 *
 416 *      Format up an SPI header for a transfer
 417 *
 418 *      FIXME: endianness?
 419 */
 420static void ifx_spi_setup_spi_header(unsigned char *txbuffer, int tx_count,
 421                                        unsigned char more)
 422{
 423        *(u16 *)(txbuffer) = tx_count;
 424        *(u16 *)(txbuffer+2) = IFX_SPI_PAYLOAD_SIZE;
 425        txbuffer[1] |= (more << IFX_SPI_MORE_BIT) & IFX_SPI_MORE_MASK;
 426}
 427
 428/**
 429 *      ifx_spi_prepare_tx_buffer       -       prepare transmit frame
 430 *      @ifx_dev: our SPI device
 431 *
 432 *      The transmit buffr needs a header and various other bits of
 433 *      information followed by as much data as we can pull from the FIFO
 434 *      and transfer. This function formats up a suitable buffer in the
 435 *      ifx_dev->tx_buffer
 436 *
 437 *      FIXME: performance - should we wake the tty when the queue is half
 438 *                           empty ?
 439 */
 440static int ifx_spi_prepare_tx_buffer(struct ifx_spi_device *ifx_dev)
 441{
 442        int temp_count;
 443        int queue_length;
 444        int tx_count;
 445        unsigned char *tx_buffer;
 446
 447        tx_buffer = ifx_dev->tx_buffer;
 448
 449        /* make room for required SPI header */
 450        tx_buffer += IFX_SPI_HEADER_OVERHEAD;
 451        tx_count = IFX_SPI_HEADER_OVERHEAD;
 452
 453        /* clear to signal no more data if this turns out to be the
 454         * last buffer sent in a sequence */
 455        ifx_dev->spi_more = 0;
 456
 457        /* if modem cts is set, just send empty buffer */
 458        if (!ifx_dev->spi_slave_cts) {
 459                /* see if there's tx data */
 460                queue_length = kfifo_len(&ifx_dev->tx_fifo);
 461                if (queue_length != 0) {
 462                        /* data to mux -- see if there's room for it */
 463                        temp_count = min(queue_length, IFX_SPI_PAYLOAD_SIZE);
 464                        temp_count = kfifo_out_locked(&ifx_dev->tx_fifo,
 465                                        tx_buffer, temp_count,
 466                                        &ifx_dev->fifo_lock);
 467
 468                        /* update buffer pointer and data count in message */
 469                        tx_buffer += temp_count;
 470                        tx_count += temp_count;
 471                        if (temp_count == queue_length)
 472                                /* poke port to get more data */
 473                                tty_port_tty_wakeup(&ifx_dev->tty_port);
 474                        else /* more data in port, use next SPI message */
 475                                ifx_dev->spi_more = 1;
 476                }
 477        }
 478        /* have data and info for header -- set up SPI header in buffer */
 479        /* spi header needs payload size, not entire buffer size */
 480        ifx_spi_setup_spi_header(ifx_dev->tx_buffer,
 481                                        tx_count-IFX_SPI_HEADER_OVERHEAD,
 482                                        ifx_dev->spi_more);
 483        /* swap actual data in the buffer */
 484        ifx_dev->swap_buf((ifx_dev->tx_buffer), tx_count,
 485                &ifx_dev->tx_buffer[IFX_SPI_TRANSFER_SIZE]);
 486        return tx_count;
 487}
 488
 489/**
 490 *      ifx_spi_write           -       line discipline write
 491 *      @tty: our tty device
 492 *      @buf: pointer to buffer to write (kernel space)
 493 *      @count: size of buffer
 494 *
 495 *      Write the characters we have been given into the FIFO. If the device
 496 *      is not active then activate it, when the SRDY line is asserted back
 497 *      this will commence I/O
 498 */
 499static int ifx_spi_write(struct tty_struct *tty, const unsigned char *buf,
 500                         int count)
 501{
 502        struct ifx_spi_device *ifx_dev = tty->driver_data;
 503        unsigned char *tmp_buf = (unsigned char *)buf;
 504        unsigned long flags;
 505        bool is_fifo_empty;
 506        int tx_count;
 507
 508        spin_lock_irqsave(&ifx_dev->fifo_lock, flags);
 509        is_fifo_empty = kfifo_is_empty(&ifx_dev->tx_fifo);
 510        tx_count = kfifo_in(&ifx_dev->tx_fifo, tmp_buf, count);
 511        spin_unlock_irqrestore(&ifx_dev->fifo_lock, flags);
 512        if (is_fifo_empty)
 513                mrdy_assert(ifx_dev);
 514
 515        return tx_count;
 516}
 517
 518/**
 519 *      ifx_spi_chars_in_buffer -       line discipline helper
 520 *      @tty: our tty device
 521 *
 522 *      Report how much data we can accept before we drop bytes. As we use
 523 *      a simple FIFO this is nice and easy.
 524 */
 525static int ifx_spi_write_room(struct tty_struct *tty)
 526{
 527        struct ifx_spi_device *ifx_dev = tty->driver_data;
 528        return IFX_SPI_FIFO_SIZE - kfifo_len(&ifx_dev->tx_fifo);
 529}
 530
 531/**
 532 *      ifx_spi_chars_in_buffer -       line discipline helper
 533 *      @tty: our tty device
 534 *
 535 *      Report how many characters we have buffered. In our case this is the
 536 *      number of bytes sitting in our transmit FIFO.
 537 */
 538static int ifx_spi_chars_in_buffer(struct tty_struct *tty)
 539{
 540        struct ifx_spi_device *ifx_dev = tty->driver_data;
 541        return kfifo_len(&ifx_dev->tx_fifo);
 542}
 543
 544/**
 545 *      ifx_port_hangup
 546 *      @port: our tty port
 547 *
 548 *      tty port hang up. Called when tty_hangup processing is invoked either
 549 *      by loss of carrier, or by software (eg vhangup). Serialized against
 550 *      activate/shutdown by the tty layer.
 551 */
 552static void ifx_spi_hangup(struct tty_struct *tty)
 553{
 554        struct ifx_spi_device *ifx_dev = tty->driver_data;
 555        tty_port_hangup(&ifx_dev->tty_port);
 556}
 557
 558/**
 559 *      ifx_port_activate
 560 *      @port: our tty port
 561 *
 562 *      tty port activate method - called for first open. Serialized
 563 *      with hangup and shutdown by the tty layer.
 564 */
 565static int ifx_port_activate(struct tty_port *port, struct tty_struct *tty)
 566{
 567        struct ifx_spi_device *ifx_dev =
 568                container_of(port, struct ifx_spi_device, tty_port);
 569
 570        /* clear any old data; can't do this in 'close' */
 571        kfifo_reset(&ifx_dev->tx_fifo);
 572
 573        /* clear any flag which may be set in port shutdown procedure */
 574        clear_bit(IFX_SPI_STATE_IO_IN_PROGRESS, &ifx_dev->flags);
 575        clear_bit(IFX_SPI_STATE_IO_READY, &ifx_dev->flags);
 576
 577        /* put port data into this tty */
 578        tty->driver_data = ifx_dev;
 579
 580        /* allows flip string push from int context */
 581        port->low_latency = 1;
 582
 583        /* set flag to allows data transfer */
 584        set_bit(IFX_SPI_STATE_IO_AVAILABLE, &ifx_dev->flags);
 585
 586        return 0;
 587}
 588
 589/**
 590 *      ifx_port_shutdown
 591 *      @port: our tty port
 592 *
 593 *      tty port shutdown method - called for last port close. Serialized
 594 *      with hangup and activate by the tty layer.
 595 */
 596static void ifx_port_shutdown(struct tty_port *port)
 597{
 598        struct ifx_spi_device *ifx_dev =
 599                container_of(port, struct ifx_spi_device, tty_port);
 600
 601        clear_bit(IFX_SPI_STATE_IO_AVAILABLE, &ifx_dev->flags);
 602        mrdy_set_low(ifx_dev);
 603        del_timer(&ifx_dev->spi_timer);
 604        clear_bit(IFX_SPI_STATE_TIMER_PENDING, &ifx_dev->flags);
 605        tasklet_kill(&ifx_dev->io_work_tasklet);
 606}
 607
 608static const struct tty_port_operations ifx_tty_port_ops = {
 609        .activate = ifx_port_activate,
 610        .shutdown = ifx_port_shutdown,
 611};
 612
 613static const struct tty_operations ifx_spi_serial_ops = {
 614        .open = ifx_spi_open,
 615        .close = ifx_spi_close,
 616        .write = ifx_spi_write,
 617        .hangup = ifx_spi_hangup,
 618        .write_room = ifx_spi_write_room,
 619        .chars_in_buffer = ifx_spi_chars_in_buffer,
 620        .tiocmget = ifx_spi_tiocmget,
 621        .tiocmset = ifx_spi_tiocmset,
 622};
 623
 624/**
 625 *      ifx_spi_insert_fip_string       -       queue received data
 626 *      @ifx_ser: our SPI device
 627 *      @chars: buffer we have received
 628 *      @size: number of chars reeived
 629 *
 630 *      Queue bytes to the tty assuming the tty side is currently open. If
 631 *      not the discard the data.
 632 */
 633static void ifx_spi_insert_flip_string(struct ifx_spi_device *ifx_dev,
 634                                    unsigned char *chars, size_t size)
 635{
 636        tty_insert_flip_string(&ifx_dev->tty_port, chars, size);
 637        tty_flip_buffer_push(&ifx_dev->tty_port);
 638}
 639
 640/**
 641 *      ifx_spi_complete        -       SPI transfer completed
 642 *      @ctx: our SPI device
 643 *
 644 *      An SPI transfer has completed. Process any received data and kick off
 645 *      any further transmits we can commence.
 646 */
 647static void ifx_spi_complete(void *ctx)
 648{
 649        struct ifx_spi_device *ifx_dev = ctx;
 650        int length;
 651        int actual_length;
 652        unsigned char more;
 653        unsigned char cts;
 654        int local_write_pending = 0;
 655        int queue_length;
 656        int srdy;
 657        int decode_result;
 658
 659        mrdy_set_low(ifx_dev);
 660
 661        if (!ifx_dev->spi_msg.status) {
 662                /* check header validity, get comm flags */
 663                ifx_dev->swap_buf(ifx_dev->rx_buffer, IFX_SPI_HEADER_OVERHEAD,
 664                        &ifx_dev->rx_buffer[IFX_SPI_HEADER_OVERHEAD]);
 665                decode_result = ifx_spi_decode_spi_header(ifx_dev->rx_buffer,
 666                                &length, &more, &cts);
 667                if (decode_result == IFX_SPI_HEADER_0) {
 668                        dev_dbg(&ifx_dev->spi_dev->dev,
 669                                "ignore input: invalid header 0");
 670                        ifx_dev->spi_slave_cts = 0;
 671                        goto complete_exit;
 672                } else if (decode_result == IFX_SPI_HEADER_F) {
 673                        dev_dbg(&ifx_dev->spi_dev->dev,
 674                                "ignore input: invalid header F");
 675                        goto complete_exit;
 676                }
 677
 678                ifx_dev->spi_slave_cts = cts;
 679
 680                actual_length = min((unsigned int)length,
 681                                        ifx_dev->spi_msg.actual_length);
 682                ifx_dev->swap_buf(
 683                        (ifx_dev->rx_buffer + IFX_SPI_HEADER_OVERHEAD),
 684                         actual_length,
 685                         &ifx_dev->rx_buffer[IFX_SPI_TRANSFER_SIZE]);
 686                ifx_spi_insert_flip_string(
 687                        ifx_dev,
 688                        ifx_dev->rx_buffer + IFX_SPI_HEADER_OVERHEAD,
 689                        (size_t)actual_length);
 690        } else {
 691                dev_dbg(&ifx_dev->spi_dev->dev, "SPI transfer error %d",
 692                       ifx_dev->spi_msg.status);
 693        }
 694
 695complete_exit:
 696        if (ifx_dev->write_pending) {
 697                ifx_dev->write_pending = 0;
 698                local_write_pending = 1;
 699        }
 700
 701        clear_bit(IFX_SPI_STATE_IO_IN_PROGRESS, &(ifx_dev->flags));
 702
 703        queue_length = kfifo_len(&ifx_dev->tx_fifo);
 704        srdy = gpio_get_value(ifx_dev->gpio.srdy);
 705        if (!srdy)
 706                ifx_spi_power_state_clear(ifx_dev, IFX_SPI_POWER_SRDY);
 707
 708        /* schedule output if there is more to do */
 709        if (test_and_clear_bit(IFX_SPI_STATE_IO_READY, &ifx_dev->flags))
 710                tasklet_schedule(&ifx_dev->io_work_tasklet);
 711        else {
 712                if (more || ifx_dev->spi_more || queue_length > 0 ||
 713                        local_write_pending) {
 714                        if (ifx_dev->spi_slave_cts) {
 715                                if (more)
 716                                        mrdy_assert(ifx_dev);
 717                        } else
 718                                mrdy_assert(ifx_dev);
 719                } else {
 720                        /*
 721                         * poke line discipline driver if any for more data
 722                         * may or may not get more data to write
 723                         * for now, say not busy
 724                         */
 725                        ifx_spi_power_state_clear(ifx_dev,
 726                                                  IFX_SPI_POWER_DATA_PENDING);
 727                        tty_port_tty_wakeup(&ifx_dev->tty_port);
 728                }
 729        }
 730}
 731
 732/**
 733 *      ifx_spio_io             -       I/O tasklet
 734 *      @data: our SPI device
 735 *
 736 *      Queue data for transmission if possible and then kick off the
 737 *      transfer.
 738 */
 739static void ifx_spi_io(unsigned long data)
 740{
 741        int retval;
 742        struct ifx_spi_device *ifx_dev = (struct ifx_spi_device *) data;
 743
 744        if (!test_and_set_bit(IFX_SPI_STATE_IO_IN_PROGRESS, &ifx_dev->flags) &&
 745                test_bit(IFX_SPI_STATE_IO_AVAILABLE, &ifx_dev->flags)) {
 746                if (ifx_dev->gpio.unack_srdy_int_nb > 0)
 747                        ifx_dev->gpio.unack_srdy_int_nb--;
 748
 749                ifx_spi_prepare_tx_buffer(ifx_dev);
 750
 751                spi_message_init(&ifx_dev->spi_msg);
 752                INIT_LIST_HEAD(&ifx_dev->spi_msg.queue);
 753
 754                ifx_dev->spi_msg.context = ifx_dev;
 755                ifx_dev->spi_msg.complete = ifx_spi_complete;
 756
 757                /* set up our spi transfer */
 758                /* note len is BYTES, not transfers */
 759                ifx_dev->spi_xfer.len = IFX_SPI_TRANSFER_SIZE;
 760                ifx_dev->spi_xfer.cs_change = 0;
 761                ifx_dev->spi_xfer.speed_hz = ifx_dev->spi_dev->max_speed_hz;
 762                /* ifx_dev->spi_xfer.speed_hz = 390625; */
 763                ifx_dev->spi_xfer.bits_per_word =
 764                        ifx_dev->spi_dev->bits_per_word;
 765
 766                ifx_dev->spi_xfer.tx_buf = ifx_dev->tx_buffer;
 767                ifx_dev->spi_xfer.rx_buf = ifx_dev->rx_buffer;
 768
 769                /*
 770                 * setup dma pointers
 771                 */
 772                if (ifx_dev->use_dma) {
 773                        ifx_dev->spi_msg.is_dma_mapped = 1;
 774                        ifx_dev->tx_dma = ifx_dev->tx_bus;
 775                        ifx_dev->rx_dma = ifx_dev->rx_bus;
 776                        ifx_dev->spi_xfer.tx_dma = ifx_dev->tx_dma;
 777                        ifx_dev->spi_xfer.rx_dma = ifx_dev->rx_dma;
 778                } else {
 779                        ifx_dev->spi_msg.is_dma_mapped = 0;
 780                        ifx_dev->tx_dma = (dma_addr_t)0;
 781                        ifx_dev->rx_dma = (dma_addr_t)0;
 782                        ifx_dev->spi_xfer.tx_dma = (dma_addr_t)0;
 783                        ifx_dev->spi_xfer.rx_dma = (dma_addr_t)0;
 784                }
 785
 786                spi_message_add_tail(&ifx_dev->spi_xfer, &ifx_dev->spi_msg);
 787
 788                /* Assert MRDY. This may have already been done by the write
 789                 * routine.
 790                 */
 791                mrdy_assert(ifx_dev);
 792
 793                retval = spi_async(ifx_dev->spi_dev, &ifx_dev->spi_msg);
 794                if (retval) {
 795                        clear_bit(IFX_SPI_STATE_IO_IN_PROGRESS,
 796                                  &ifx_dev->flags);
 797                        tasklet_schedule(&ifx_dev->io_work_tasklet);
 798                        return;
 799                }
 800        } else
 801                ifx_dev->write_pending = 1;
 802}
 803
 804/**
 805 *      ifx_spi_free_port       -       free up the tty side
 806 *      @ifx_dev: IFX device going away
 807 *
 808 *      Unregister and free up a port when the device goes away
 809 */
 810static void ifx_spi_free_port(struct ifx_spi_device *ifx_dev)
 811{
 812        if (ifx_dev->tty_dev)
 813                tty_unregister_device(tty_drv, ifx_dev->minor);
 814        tty_port_destroy(&ifx_dev->tty_port);
 815        kfifo_free(&ifx_dev->tx_fifo);
 816}
 817
 818/**
 819 *      ifx_spi_create_port     -       create a new port
 820 *      @ifx_dev: our spi device
 821 *
 822 *      Allocate and initialise the tty port that goes with this interface
 823 *      and add it to the tty layer so that it can be opened.
 824 */
 825static int ifx_spi_create_port(struct ifx_spi_device *ifx_dev)
 826{
 827        int ret = 0;
 828        struct tty_port *pport = &ifx_dev->tty_port;
 829
 830        spin_lock_init(&ifx_dev->fifo_lock);
 831        lockdep_set_class_and_subclass(&ifx_dev->fifo_lock,
 832                &ifx_spi_key, 0);
 833
 834        if (kfifo_alloc(&ifx_dev->tx_fifo, IFX_SPI_FIFO_SIZE, GFP_KERNEL)) {
 835                ret = -ENOMEM;
 836                goto error_ret;
 837        }
 838
 839        tty_port_init(pport);
 840        pport->ops = &ifx_tty_port_ops;
 841        ifx_dev->minor = IFX_SPI_TTY_ID;
 842        ifx_dev->tty_dev = tty_port_register_device(pport, tty_drv,
 843                        ifx_dev->minor, &ifx_dev->spi_dev->dev);
 844        if (IS_ERR(ifx_dev->tty_dev)) {
 845                dev_dbg(&ifx_dev->spi_dev->dev,
 846                        "%s: registering tty device failed", __func__);
 847                ret = PTR_ERR(ifx_dev->tty_dev);
 848                goto error_port;
 849        }
 850        return 0;
 851
 852error_port:
 853        tty_port_destroy(pport);
 854error_ret:
 855        ifx_spi_free_port(ifx_dev);
 856        return ret;
 857}
 858
 859/**
 860 *      ifx_spi_handle_srdy             -       handle SRDY
 861 *      @ifx_dev: device asserting SRDY
 862 *
 863 *      Check our device state and see what we need to kick off when SRDY
 864 *      is asserted. This usually means killing the timer and firing off the
 865 *      I/O processing.
 866 */
 867static void ifx_spi_handle_srdy(struct ifx_spi_device *ifx_dev)
 868{
 869        if (test_bit(IFX_SPI_STATE_TIMER_PENDING, &ifx_dev->flags)) {
 870                del_timer(&ifx_dev->spi_timer);
 871                clear_bit(IFX_SPI_STATE_TIMER_PENDING, &ifx_dev->flags);
 872        }
 873
 874        ifx_spi_power_state_set(ifx_dev, IFX_SPI_POWER_SRDY);
 875
 876        if (!test_bit(IFX_SPI_STATE_IO_IN_PROGRESS, &ifx_dev->flags))
 877                tasklet_schedule(&ifx_dev->io_work_tasklet);
 878        else
 879                set_bit(IFX_SPI_STATE_IO_READY, &ifx_dev->flags);
 880}
 881
 882/**
 883 *      ifx_spi_srdy_interrupt  -       SRDY asserted
 884 *      @irq: our IRQ number
 885 *      @dev: our ifx device
 886 *
 887 *      The modem asserted SRDY. Handle the srdy event
 888 */
 889static irqreturn_t ifx_spi_srdy_interrupt(int irq, void *dev)
 890{
 891        struct ifx_spi_device *ifx_dev = dev;
 892        ifx_dev->gpio.unack_srdy_int_nb++;
 893        ifx_spi_handle_srdy(ifx_dev);
 894        return IRQ_HANDLED;
 895}
 896
 897/**
 898 *      ifx_spi_reset_interrupt -       Modem has changed reset state
 899 *      @irq: interrupt number
 900 *      @dev: our device pointer
 901 *
 902 *      The modem has either entered or left reset state. Check the GPIO
 903 *      line to see which.
 904 *
 905 *      FIXME: review locking on MR_INPROGRESS versus
 906 *      parallel unsolicited reset/solicited reset
 907 */
 908static irqreturn_t ifx_spi_reset_interrupt(int irq, void *dev)
 909{
 910        struct ifx_spi_device *ifx_dev = dev;
 911        int val = gpio_get_value(ifx_dev->gpio.reset_out);
 912        int solreset = test_bit(MR_START, &ifx_dev->mdm_reset_state);
 913
 914        if (val == 0) {
 915                /* entered reset */
 916                set_bit(MR_INPROGRESS, &ifx_dev->mdm_reset_state);
 917                if (!solreset) {
 918                        /* unsolicited reset  */
 919                        tty_port_tty_hangup(&ifx_dev->tty_port, false);
 920                }
 921        } else {
 922                /* exited reset */
 923                clear_bit(MR_INPROGRESS, &ifx_dev->mdm_reset_state);
 924                if (solreset) {
 925                        set_bit(MR_COMPLETE, &ifx_dev->mdm_reset_state);
 926                        wake_up(&ifx_dev->mdm_reset_wait);
 927                }
 928        }
 929        return IRQ_HANDLED;
 930}
 931
 932/**
 933 *      ifx_spi_free_device - free device
 934 *      @ifx_dev: device to free
 935 *
 936 *      Free the IFX device
 937 */
 938static void ifx_spi_free_device(struct ifx_spi_device *ifx_dev)
 939{
 940        ifx_spi_free_port(ifx_dev);
 941        dma_free_coherent(&ifx_dev->spi_dev->dev,
 942                                IFX_SPI_TRANSFER_SIZE,
 943                                ifx_dev->tx_buffer,
 944                                ifx_dev->tx_bus);
 945        dma_free_coherent(&ifx_dev->spi_dev->dev,
 946                                IFX_SPI_TRANSFER_SIZE,
 947                                ifx_dev->rx_buffer,
 948                                ifx_dev->rx_bus);
 949}
 950
 951/**
 952 *      ifx_spi_reset   -       reset modem
 953 *      @ifx_dev: modem to reset
 954 *
 955 *      Perform a reset on the modem
 956 */
 957static int ifx_spi_reset(struct ifx_spi_device *ifx_dev)
 958{
 959        int ret;
 960        /*
 961         * set up modem power, reset
 962         *
 963         * delays are required on some platforms for the modem
 964         * to reset properly
 965         */
 966        set_bit(MR_START, &ifx_dev->mdm_reset_state);
 967        gpio_set_value(ifx_dev->gpio.po, 0);
 968        gpio_set_value(ifx_dev->gpio.reset, 0);
 969        msleep(25);
 970        gpio_set_value(ifx_dev->gpio.reset, 1);
 971        msleep(1);
 972        gpio_set_value(ifx_dev->gpio.po, 1);
 973        msleep(1);
 974        gpio_set_value(ifx_dev->gpio.po, 0);
 975        ret = wait_event_timeout(ifx_dev->mdm_reset_wait,
 976                                 test_bit(MR_COMPLETE,
 977                                          &ifx_dev->mdm_reset_state),
 978                                 IFX_RESET_TIMEOUT);
 979        if (!ret)
 980                dev_warn(&ifx_dev->spi_dev->dev, "Modem reset timeout: (state:%lx)",
 981                         ifx_dev->mdm_reset_state);
 982
 983        ifx_dev->mdm_reset_state = 0;
 984        return ret;
 985}
 986
 987/**
 988 *      ifx_spi_spi_probe       -       probe callback
 989 *      @spi: our possible matching SPI device
 990 *
 991 *      Probe for a 6x60 modem on SPI bus. Perform any needed device and
 992 *      GPIO setup.
 993 *
 994 *      FIXME:
 995 *      -       Support for multiple devices
 996 *      -       Split out MID specific GPIO handling eventually
 997 */
 998
 999static int ifx_spi_spi_probe(struct spi_device *spi)
1000{
1001        int ret;
1002        int srdy;
1003        struct ifx_modem_platform_data *pl_data;
1004        struct ifx_spi_device *ifx_dev;
1005
1006        if (saved_ifx_dev) {
1007                dev_dbg(&spi->dev, "ignoring subsequent detection");
1008                return -ENODEV;
1009        }
1010
1011        pl_data = dev_get_platdata(&spi->dev);
1012        if (!pl_data) {
1013                dev_err(&spi->dev, "missing platform data!");
1014                return -ENODEV;
1015        }
1016
1017        /* initialize structure to hold our device variables */
1018        ifx_dev = kzalloc(sizeof(struct ifx_spi_device), GFP_KERNEL);
1019        if (!ifx_dev) {
1020                dev_err(&spi->dev, "spi device allocation failed");
1021                return -ENOMEM;
1022        }
1023        saved_ifx_dev = ifx_dev;
1024        ifx_dev->spi_dev = spi;
1025        clear_bit(IFX_SPI_STATE_IO_IN_PROGRESS, &ifx_dev->flags);
1026        spin_lock_init(&ifx_dev->write_lock);
1027        spin_lock_init(&ifx_dev->power_lock);
1028        ifx_dev->power_status = 0;
1029        init_timer(&ifx_dev->spi_timer);
1030        ifx_dev->spi_timer.function = ifx_spi_timeout;
1031        ifx_dev->spi_timer.data = (unsigned long)ifx_dev;
1032        ifx_dev->modem = pl_data->modem_type;
1033        ifx_dev->use_dma = pl_data->use_dma;
1034        ifx_dev->max_hz = pl_data->max_hz;
1035        /* initialize spi mode, etc */
1036        spi->max_speed_hz = ifx_dev->max_hz;
1037        spi->mode = IFX_SPI_MODE | (SPI_LOOP & spi->mode);
1038        spi->bits_per_word = spi_bpw;
1039        ret = spi_setup(spi);
1040        if (ret) {
1041                dev_err(&spi->dev, "SPI setup wasn't successful %d", ret);
1042                return -ENODEV;
1043        }
1044
1045        /* init swap_buf function according to word width configuration */
1046        if (spi->bits_per_word == 32)
1047                ifx_dev->swap_buf = swap_buf_32;
1048        else if (spi->bits_per_word == 16)
1049                ifx_dev->swap_buf = swap_buf_16;
1050        else
1051                ifx_dev->swap_buf = swap_buf_8;
1052
1053        /* ensure SPI protocol flags are initialized to enable transfer */
1054        ifx_dev->spi_more = 0;
1055        ifx_dev->spi_slave_cts = 0;
1056
1057        /*initialize transfer and dma buffers */
1058        ifx_dev->tx_buffer = dma_alloc_coherent(ifx_dev->spi_dev->dev.parent,
1059                                IFX_SPI_TRANSFER_SIZE,
1060                                &ifx_dev->tx_bus,
1061                                GFP_KERNEL);
1062        if (!ifx_dev->tx_buffer) {
1063                dev_err(&spi->dev, "DMA-TX buffer allocation failed");
1064                ret = -ENOMEM;
1065                goto error_ret;
1066        }
1067        ifx_dev->rx_buffer = dma_alloc_coherent(ifx_dev->spi_dev->dev.parent,
1068                                IFX_SPI_TRANSFER_SIZE,
1069                                &ifx_dev->rx_bus,
1070                                GFP_KERNEL);
1071        if (!ifx_dev->rx_buffer) {
1072                dev_err(&spi->dev, "DMA-RX buffer allocation failed");
1073                ret = -ENOMEM;
1074                goto error_ret;
1075        }
1076
1077        /* initialize waitq for modem reset */
1078        init_waitqueue_head(&ifx_dev->mdm_reset_wait);
1079
1080        spi_set_drvdata(spi, ifx_dev);
1081        tasklet_init(&ifx_dev->io_work_tasklet, ifx_spi_io,
1082                                                (unsigned long)ifx_dev);
1083
1084        set_bit(IFX_SPI_STATE_PRESENT, &ifx_dev->flags);
1085
1086        /* create our tty port */
1087        ret = ifx_spi_create_port(ifx_dev);
1088        if (ret != 0) {
1089                dev_err(&spi->dev, "create default tty port failed");
1090                goto error_ret;
1091        }
1092
1093        ifx_dev->gpio.reset = pl_data->rst_pmu;
1094        ifx_dev->gpio.po = pl_data->pwr_on;
1095        ifx_dev->gpio.mrdy = pl_data->mrdy;
1096        ifx_dev->gpio.srdy = pl_data->srdy;
1097        ifx_dev->gpio.reset_out = pl_data->rst_out;
1098
1099        dev_info(&spi->dev, "gpios %d, %d, %d, %d, %d",
1100                 ifx_dev->gpio.reset, ifx_dev->gpio.po, ifx_dev->gpio.mrdy,
1101                 ifx_dev->gpio.srdy, ifx_dev->gpio.reset_out);
1102
1103        /* Configure gpios */
1104        ret = gpio_request(ifx_dev->gpio.reset, "ifxModem");
1105        if (ret < 0) {
1106                dev_err(&spi->dev, "Unable to allocate GPIO%d (RESET)",
1107                        ifx_dev->gpio.reset);
1108                goto error_ret;
1109        }
1110        ret += gpio_direction_output(ifx_dev->gpio.reset, 0);
1111        ret += gpio_export(ifx_dev->gpio.reset, 1);
1112        if (ret) {
1113                dev_err(&spi->dev, "Unable to configure GPIO%d (RESET)",
1114                        ifx_dev->gpio.reset);
1115                ret = -EBUSY;
1116                goto error_ret2;
1117        }
1118
1119        ret = gpio_request(ifx_dev->gpio.po, "ifxModem");
1120        ret += gpio_direction_output(ifx_dev->gpio.po, 0);
1121        ret += gpio_export(ifx_dev->gpio.po, 1);
1122        if (ret) {
1123                dev_err(&spi->dev, "Unable to configure GPIO%d (ON)",
1124                        ifx_dev->gpio.po);
1125                ret = -EBUSY;
1126                goto error_ret3;
1127        }
1128
1129        ret = gpio_request(ifx_dev->gpio.mrdy, "ifxModem");
1130        if (ret < 0) {
1131                dev_err(&spi->dev, "Unable to allocate GPIO%d (MRDY)",
1132                        ifx_dev->gpio.mrdy);
1133                goto error_ret3;
1134        }
1135        ret += gpio_export(ifx_dev->gpio.mrdy, 1);
1136        ret += gpio_direction_output(ifx_dev->gpio.mrdy, 0);
1137        if (ret) {
1138                dev_err(&spi->dev, "Unable to configure GPIO%d (MRDY)",
1139                        ifx_dev->gpio.mrdy);
1140                ret = -EBUSY;
1141                goto error_ret4;
1142        }
1143
1144        ret = gpio_request(ifx_dev->gpio.srdy, "ifxModem");
1145        if (ret < 0) {
1146                dev_err(&spi->dev, "Unable to allocate GPIO%d (SRDY)",
1147                        ifx_dev->gpio.srdy);
1148                ret = -EBUSY;
1149                goto error_ret4;
1150        }
1151        ret += gpio_export(ifx_dev->gpio.srdy, 1);
1152        ret += gpio_direction_input(ifx_dev->gpio.srdy);
1153        if (ret) {
1154                dev_err(&spi->dev, "Unable to configure GPIO%d (SRDY)",
1155                        ifx_dev->gpio.srdy);
1156                ret = -EBUSY;
1157                goto error_ret5;
1158        }
1159
1160        ret = gpio_request(ifx_dev->gpio.reset_out, "ifxModem");
1161        if (ret < 0) {
1162                dev_err(&spi->dev, "Unable to allocate GPIO%d (RESET_OUT)",
1163                        ifx_dev->gpio.reset_out);
1164                goto error_ret5;
1165        }
1166        ret += gpio_export(ifx_dev->gpio.reset_out, 1);
1167        ret += gpio_direction_input(ifx_dev->gpio.reset_out);
1168        if (ret) {
1169                dev_err(&spi->dev, "Unable to configure GPIO%d (RESET_OUT)",
1170                        ifx_dev->gpio.reset_out);
1171                ret = -EBUSY;
1172                goto error_ret6;
1173        }
1174
1175        ret = request_irq(gpio_to_irq(ifx_dev->gpio.reset_out),
1176                          ifx_spi_reset_interrupt,
1177                          IRQF_TRIGGER_RISING|IRQF_TRIGGER_FALLING, DRVNAME,
1178                (void *)ifx_dev);
1179        if (ret) {
1180                dev_err(&spi->dev, "Unable to get irq %x\n",
1181                        gpio_to_irq(ifx_dev->gpio.reset_out));
1182                goto error_ret6;
1183        }
1184
1185        ret = ifx_spi_reset(ifx_dev);
1186
1187        ret = request_irq(gpio_to_irq(ifx_dev->gpio.srdy),
1188                          ifx_spi_srdy_interrupt,
1189                          IRQF_TRIGGER_RISING, DRVNAME,
1190                          (void *)ifx_dev);
1191        if (ret) {
1192                dev_err(&spi->dev, "Unable to get irq %x",
1193                        gpio_to_irq(ifx_dev->gpio.srdy));
1194                goto error_ret7;
1195        }
1196
1197        /* set pm runtime power state and register with power system */
1198        pm_runtime_set_active(&spi->dev);
1199        pm_runtime_enable(&spi->dev);
1200
1201        /* handle case that modem is already signaling SRDY */
1202        /* no outgoing tty open at this point, this just satisfies the
1203         * modem's read and should reset communication properly
1204         */
1205        srdy = gpio_get_value(ifx_dev->gpio.srdy);
1206
1207        if (srdy) {
1208                mrdy_assert(ifx_dev);
1209                ifx_spi_handle_srdy(ifx_dev);
1210        } else
1211                mrdy_set_low(ifx_dev);
1212        return 0;
1213
1214error_ret7:
1215        free_irq(gpio_to_irq(ifx_dev->gpio.reset_out), (void *)ifx_dev);
1216error_ret6:
1217        gpio_free(ifx_dev->gpio.srdy);
1218error_ret5:
1219        gpio_free(ifx_dev->gpio.mrdy);
1220error_ret4:
1221        gpio_free(ifx_dev->gpio.reset);
1222error_ret3:
1223        gpio_free(ifx_dev->gpio.po);
1224error_ret2:
1225        gpio_free(ifx_dev->gpio.reset_out);
1226error_ret:
1227        ifx_spi_free_device(ifx_dev);
1228        saved_ifx_dev = NULL;
1229        return ret;
1230}
1231
1232/**
1233 *      ifx_spi_spi_remove      -       SPI device was removed
1234 *      @spi: SPI device
1235 *
1236 *      FIXME: We should be shutting the device down here not in
1237 *      the module unload path.
1238 */
1239
1240static int ifx_spi_spi_remove(struct spi_device *spi)
1241{
1242        struct ifx_spi_device *ifx_dev = spi_get_drvdata(spi);
1243        /* stop activity */
1244        tasklet_kill(&ifx_dev->io_work_tasklet);
1245        /* free irq */
1246        free_irq(gpio_to_irq(ifx_dev->gpio.reset_out), (void *)ifx_dev);
1247        free_irq(gpio_to_irq(ifx_dev->gpio.srdy), (void *)ifx_dev);
1248
1249        gpio_free(ifx_dev->gpio.srdy);
1250        gpio_free(ifx_dev->gpio.mrdy);
1251        gpio_free(ifx_dev->gpio.reset);
1252        gpio_free(ifx_dev->gpio.po);
1253        gpio_free(ifx_dev->gpio.reset_out);
1254
1255        /* free allocations */
1256        ifx_spi_free_device(ifx_dev);
1257
1258        saved_ifx_dev = NULL;
1259        return 0;
1260}
1261
1262/**
1263 *      ifx_spi_spi_shutdown    -       called on SPI shutdown
1264 *      @spi: SPI device
1265 *
1266 *      No action needs to be taken here
1267 */
1268
1269static void ifx_spi_spi_shutdown(struct spi_device *spi)
1270{
1271        struct ifx_spi_device *ifx_dev = spi_get_drvdata(spi);
1272
1273        ifx_modem_power_off(ifx_dev);
1274}
1275
1276/*
1277 * various suspends and resumes have nothing to do
1278 * no hardware to save state for
1279 */
1280
1281/**
1282 *      ifx_spi_pm_suspend      -       suspend modem on system suspend
1283 *      @dev: device being suspended
1284 *
1285 *      Suspend the modem. No action needed on Intel MID platforms, may
1286 *      need extending for other systems.
1287 */
1288static int ifx_spi_pm_suspend(struct device *dev)
1289{
1290        return 0;
1291}
1292
1293/**
1294 *      ifx_spi_pm_resume       -       resume modem on system resume
1295 *      @dev: device being suspended
1296 *
1297 *      Allow the modem to resume. No action needed.
1298 *
1299 *      FIXME: do we need to reset anything here ?
1300 */
1301static int ifx_spi_pm_resume(struct device *dev)
1302{
1303        return 0;
1304}
1305
1306/**
1307 *      ifx_spi_pm_runtime_resume       -       suspend modem
1308 *      @dev: device being suspended
1309 *
1310 *      Allow the modem to resume. No action needed.
1311 */
1312static int ifx_spi_pm_runtime_resume(struct device *dev)
1313{
1314        return 0;
1315}
1316
1317/**
1318 *      ifx_spi_pm_runtime_suspend      -       suspend modem
1319 *      @dev: device being suspended
1320 *
1321 *      Allow the modem to suspend and thus suspend to continue up the
1322 *      device tree.
1323 */
1324static int ifx_spi_pm_runtime_suspend(struct device *dev)
1325{
1326        return 0;
1327}
1328
1329/**
1330 *      ifx_spi_pm_runtime_idle         -       check if modem idle
1331 *      @dev: our device
1332 *
1333 *      Check conditions and queue runtime suspend if idle.
1334 */
1335static int ifx_spi_pm_runtime_idle(struct device *dev)
1336{
1337        struct spi_device *spi = to_spi_device(dev);
1338        struct ifx_spi_device *ifx_dev = spi_get_drvdata(spi);
1339
1340        if (!ifx_dev->power_status)
1341                pm_runtime_suspend(dev);
1342
1343        return 0;
1344}
1345
1346static const struct dev_pm_ops ifx_spi_pm = {
1347        .resume = ifx_spi_pm_resume,
1348        .suspend = ifx_spi_pm_suspend,
1349        .runtime_resume = ifx_spi_pm_runtime_resume,
1350        .runtime_suspend = ifx_spi_pm_runtime_suspend,
1351        .runtime_idle = ifx_spi_pm_runtime_idle
1352};
1353
1354static const struct spi_device_id ifx_id_table[] = {
1355        {"ifx6160", 0},
1356        {"ifx6260", 0},
1357        { }
1358};
1359MODULE_DEVICE_TABLE(spi, ifx_id_table);
1360
1361/* spi operations */
1362static struct spi_driver ifx_spi_driver = {
1363        .driver = {
1364                .name = DRVNAME,
1365                .pm = &ifx_spi_pm,
1366                .owner = THIS_MODULE},
1367        .probe = ifx_spi_spi_probe,
1368        .shutdown = ifx_spi_spi_shutdown,
1369        .remove = ifx_spi_spi_remove,
1370        .id_table = ifx_id_table
1371};
1372
1373/**
1374 *      ifx_spi_exit    -       module exit
1375 *
1376 *      Unload the module.
1377 */
1378
1379static void __exit ifx_spi_exit(void)
1380{
1381        /* unregister */
1382        tty_unregister_driver(tty_drv);
1383        put_tty_driver(tty_drv);
1384        spi_unregister_driver((void *)&ifx_spi_driver);
1385        unregister_reboot_notifier(&ifx_modem_reboot_notifier_block);
1386}
1387
1388/**
1389 *      ifx_spi_init            -       module entry point
1390 *
1391 *      Initialise the SPI and tty interfaces for the IFX SPI driver
1392 *      We need to initialize upper-edge spi driver after the tty
1393 *      driver because otherwise the spi probe will race
1394 */
1395
1396static int __init ifx_spi_init(void)
1397{
1398        int result;
1399
1400        tty_drv = alloc_tty_driver(1);
1401        if (!tty_drv) {
1402                pr_err("%s: alloc_tty_driver failed", DRVNAME);
1403                return -ENOMEM;
1404        }
1405
1406        tty_drv->driver_name = DRVNAME;
1407        tty_drv->name = TTYNAME;
1408        tty_drv->minor_start = IFX_SPI_TTY_ID;
1409        tty_drv->type = TTY_DRIVER_TYPE_SERIAL;
1410        tty_drv->subtype = SERIAL_TYPE_NORMAL;
1411        tty_drv->flags = TTY_DRIVER_REAL_RAW | TTY_DRIVER_DYNAMIC_DEV;
1412        tty_drv->init_termios = tty_std_termios;
1413
1414        tty_set_operations(tty_drv, &ifx_spi_serial_ops);
1415
1416        result = tty_register_driver(tty_drv);
1417        if (result) {
1418                pr_err("%s: tty_register_driver failed(%d)",
1419                        DRVNAME, result);
1420                goto err_free_tty;
1421        }
1422
1423        result = spi_register_driver((void *)&ifx_spi_driver);
1424        if (result) {
1425                pr_err("%s: spi_register_driver failed(%d)",
1426                        DRVNAME, result);
1427                goto err_unreg_tty;
1428        }
1429
1430        result = register_reboot_notifier(&ifx_modem_reboot_notifier_block);
1431        if (result) {
1432                pr_err("%s: register ifx modem reboot notifier failed(%d)",
1433                        DRVNAME, result);
1434                goto err_unreg_spi;
1435        }
1436
1437        return 0;
1438err_unreg_spi:
1439        spi_unregister_driver((void *)&ifx_spi_driver);
1440err_unreg_tty:
1441        tty_unregister_driver(tty_drv);
1442err_free_tty:
1443        put_tty_driver(tty_drv);
1444
1445        return result;
1446}
1447
1448module_init(ifx_spi_init);
1449module_exit(ifx_spi_exit);
1450
1451MODULE_AUTHOR("Intel");
1452MODULE_DESCRIPTION("IFX6x60 spi driver");
1453MODULE_LICENSE("GPL");
1454MODULE_INFO(Version, "0.1-IFX6x60");
1455