drivers/tty/serial/max3107-aava.c

   1 /*
   2  *  max3107.c - spi uart protocol driver for Maxim 3107
   3  *  Based on max3100.c
   4  *      by Christian Pellegrin <chripell@evolware.org>
   5  *  and max3110.c
   6  *      by Feng Tang <feng.tang@intel.com>
   7  *
   8  *  Copyright (C) Aavamobile 2009
   9  *
  10  * ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
  11  *
  12  *  This program is free software; you can redistribute it and/or modify
  13  *  it under the terms of the GNU General Public License as published by
  14  *  the Free Software Foundation; either version 2 of the License, or
  15  *  (at your option) any later version.
  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., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
  25  *
  26  * ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
  27  *
  28  */
  29
  30 #include <linux/delay.h>
  31 #include <linux/device.h>
  32 #include <linux/serial_core.h>
  33 #include <linux/serial.h>
  34 #include <linux/spi/spi.h>
  35 #include <linux/freezer.h>
  36 #include <linux/platform_device.h>
  37 #include <linux/gpio.h>
  38 #include <linux/sfi.h>
  39 #include <linux/module.h>
  40 #include <asm/mrst.h>
  41 #include "max3107.h"
  42
  43 /* GPIO direction to input function */
  44 static int max3107_gpio_direction_in(struct gpio_chip *chip, unsigned offset)
  45 {
  46         struct max3107_port *s = container_of(chip, struct max3107_port, chip);
  47         u16 buf[1];             /* Buffer for SPI transfer */
  48
  49         if (offset >= MAX3107_GPIO_COUNT) {
  50                 dev_err(&s->spi->dev, "Invalid GPIO\n");
  51                 return -EINVAL;
  52         }
  53
  54         /* Read current GPIO configuration register */
  55         buf[0] = MAX3107_GPIOCFG_REG;
  56         /* Perform SPI transfer */
  57         if (max3107_rw(s, (u8 *)buf, (u8 *)buf, 2)) {
  58                 dev_err(&s->spi->dev, "SPI transfer GPIO read failed\n");
  59                 return -EIO;
  60         }
  61         buf[0] &= MAX3107_SPI_RX_DATA_MASK;
  62
  63         /* Set GPIO to input */
  64         buf[0] &= ~(0x0001 << offset);
  65
  66         /* Write new GPIO configuration register value */
  67         buf[0] |= (MAX3107_WRITE_BIT | MAX3107_GPIOCFG_REG);
  68         /* Perform SPI transfer */
  69         if (max3107_rw(s, (u8 *)buf, NULL, 2)) {
  70                 dev_err(&s->spi->dev, "SPI transfer GPIO write failed\n");
  71                 return -EIO;
  72         }
  73         return 0;
  74 }
  75
  76 /* GPIO direction to output function */
  77 static int max3107_gpio_direction_out(struct gpio_chip *chip, unsigned offset,
  78                                         int value)
  79 {
  80         struct max3107_port *s = container_of(chip, struct max3107_port, chip);
  81         u16 buf[2];     /* Buffer for SPI transfers */
  82
  83         if (offset >= MAX3107_GPIO_COUNT) {
  84                 dev_err(&s->spi->dev, "Invalid GPIO\n");
  85                 return -EINVAL;
  86         }
  87
  88         /* Read current GPIO configuration and data registers */
  89         buf[0] = MAX3107_GPIOCFG_REG;
  90         buf[1] = MAX3107_GPIODATA_REG;
  91         /* Perform SPI transfer */
  92         if (max3107_rw(s, (u8 *)buf, (u8 *)buf, 4)) {
  93                 dev_err(&s->spi->dev, "SPI transfer gpio failed\n");
  94                 return -EIO;
  95         }
  96         buf[0] &= MAX3107_SPI_RX_DATA_MASK;
  97         buf[1] &= MAX3107_SPI_RX_DATA_MASK;
  98
  99         /* Set GPIO to output */
 100         buf[0] |= (0x0001 << offset);
 101         /* Set value */
 102         if (value)
 103                 buf[1] |= (0x0001 << offset);
 104         else
 105                 buf[1] &= ~(0x0001 << offset);
 106
 107         /* Write new GPIO configuration and data register values */
 108         buf[0] |= (MAX3107_WRITE_BIT | MAX3107_GPIOCFG_REG);
 109         buf[1] |= (MAX3107_WRITE_BIT | MAX3107_GPIODATA_REG);
 110         /* Perform SPI transfer */
 111         if (max3107_rw(s, (u8 *)buf, NULL, 4)) {
 112                 dev_err(&s->spi->dev,
 113                         "SPI transfer for GPIO conf data w failed\n");
 114                 return -EIO;
 115         }
 116         return 0;
 117 }
 118
 119 /* GPIO value query function */
 120 static int max3107_gpio_get(struct gpio_chip *chip, unsigned offset)
 121 {
 122         struct max3107_port *s = container_of(chip, struct max3107_port, chip);
 123         u16 buf[1];     /* Buffer for SPI transfer */
 124
 125         if (offset >= MAX3107_GPIO_COUNT) {
 126                 dev_err(&s->spi->dev, "Invalid GPIO\n");
 127                 return -EINVAL;
 128         }
 129
 130         /* Read current GPIO data register */
 131         buf[0] = MAX3107_GPIODATA_REG;
 132         /* Perform SPI transfer */
 133         if (max3107_rw(s, (u8 *)buf, (u8 *)buf, 2)) {
 134                 dev_err(&s->spi->dev, "SPI transfer GPIO data r failed\n");
 135                 return -EIO;
 136         }
 137         buf[0] &= MAX3107_SPI_RX_DATA_MASK;
 138
 139         /* Return value */
 140         return buf[0] & (0x0001 << offset);
 141 }
 142
 143 /* GPIO value set function */
 144 static void max3107_gpio_set(struct gpio_chip *chip, unsigned offset, int value)
 145 {
 146         struct max3107_port *s = container_of(chip, struct max3107_port, chip);
 147         u16 buf[2];     /* Buffer for SPI transfers */
 148
 149         if (offset >= MAX3107_GPIO_COUNT) {
 150                 dev_err(&s->spi->dev, "Invalid GPIO\n");
 151                 return;
 152         }
 153
 154         /* Read current GPIO configuration registers*/
 155         buf[0] = MAX3107_GPIODATA_REG;
 156         buf[1] = MAX3107_GPIOCFG_REG;
 157         /* Perform SPI transfer */
 158         if (max3107_rw(s, (u8 *)buf, (u8 *)buf, 4)) {
 159                 dev_err(&s->spi->dev,
 160                         "SPI transfer for GPIO data and config read failed\n");
 161                 return;
 162         }
 163         buf[0] &= MAX3107_SPI_RX_DATA_MASK;
 164         buf[1] &= MAX3107_SPI_RX_DATA_MASK;
 165
 166         if (!(buf[1] & (0x0001 << offset))) {
 167                 /* Configured as input, can't set value */
 168                 dev_warn(&s->spi->dev,
 169                                 "Trying to set value for input GPIO\n");
 170                 return;
 171         }
 172
 173         /* Set value */
 174         if (value)
 175                 buf[0] |= (0x0001 << offset);
 176         else
 177                 buf[0] &= ~(0x0001 << offset);
 178
 179         /* Write new GPIO data register value */
 180         buf[0] |= (MAX3107_WRITE_BIT | MAX3107_GPIODATA_REG);
 181         /* Perform SPI transfer */
 182         if (max3107_rw(s, (u8 *)buf, NULL, 2))
 183                 dev_err(&s->spi->dev, "SPI transfer GPIO data w failed\n");
 184 }
 185
 186 /* GPIO chip data */
 187 static struct gpio_chip max3107_gpio_chip = {
 188         .owner                  = THIS_MODULE,
 189         .direction_input        = max3107_gpio_direction_in,
 190         .direction_output       = max3107_gpio_direction_out,
 191         .get                    = max3107_gpio_get,
 192         .set                    = max3107_gpio_set,
 193         .can_sleep              = 1,
 194         .base                   = MAX3107_GPIO_BASE,
 195         .ngpio                  = MAX3107_GPIO_COUNT,
 196 };
 197
 198 /**
 199  *      max3107_aava_reset      -       reset on AAVA systems
 200  *      @spi: The SPI device we are probing
 201  *
 202  *      Reset the device ready for probing.
 203  */
 204
 205 static int max3107_aava_reset(struct spi_device *spi)
 206 {
 207         /* Reset the chip */
 208         if (gpio_request(MAX3107_RESET_GPIO, "max3107")) {
 209                 pr_err("Requesting RESET GPIO failed\n");
 210                 return -EIO;
 211         }
 212         if (gpio_direction_output(MAX3107_RESET_GPIO, 0)) {
 213                 pr_err("Setting RESET GPIO to 0 failed\n");
 214                 gpio_free(MAX3107_RESET_GPIO);
 215                 return -EIO;
 216         }
 217         msleep(MAX3107_RESET_DELAY);
 218         if (gpio_direction_output(MAX3107_RESET_GPIO, 1)) {
 219                 pr_err("Setting RESET GPIO to 1 failed\n");
 220                 gpio_free(MAX3107_RESET_GPIO);
 221                 return -EIO;
 222         }
 223         gpio_free(MAX3107_RESET_GPIO);
 224         msleep(MAX3107_WAKEUP_DELAY);
 225         return 0;
 226 }
 227
 228 static int max3107_aava_configure(struct max3107_port *s)
 229 {
 230         int retval;
 231
 232         /* Initialize GPIO chip data */
 233         s->chip = max3107_gpio_chip;
 234         s->chip.label = s->spi->modalias;
 235         s->chip.dev = &s->spi->dev;
 236
 237         /* Add GPIO chip */
 238         retval = gpiochip_add(&s->chip);
 239         if (retval) {
 240                 dev_err(&s->spi->dev, "Adding GPIO chip failed\n");
 241                 return retval;
 242         }
 243
 244         /* Temporary fix for EV2 boot problems, set modem reset to 0 */
 245         max3107_gpio_direction_out(&s->chip, 3, 0);
 246         return 0;
 247 }
 248
 249 #if 0
 250 /* This will get enabled once we have the board stuff merged for this
 251    specific case */
 252
 253 static const struct baud_table brg13_ext[] = {
 254         { 300,    MAX3107_BRG13_B300 },
 255         { 600,    MAX3107_BRG13_B600 },
 256         { 1200,   MAX3107_BRG13_B1200 },
 257         { 2400,   MAX3107_BRG13_B2400 },
 258         { 4800,   MAX3107_BRG13_B4800 },
 259         { 9600,   MAX3107_BRG13_B9600 },
 260         { 19200,  MAX3107_BRG13_B19200 },
 261         { 57600,  MAX3107_BRG13_B57600 },
 262         { 115200, MAX3107_BRG13_B115200 },
 263         { 230400, MAX3107_BRG13_B230400 },
 264         { 460800, MAX3107_BRG13_B460800 },
 265         { 921600, MAX3107_BRG13_B921600 },
 266         { 0, 0 }
 267 };
 268
 269 static void max3107_aava_init(struct max3107_port *s)
 270 {
 271         /*override for AAVA SC specific*/
 272         if (mrst_platform_id() == MRST_PLATFORM_AAVA_SC) {
 273                 if (get_koski_build_id() <= KOSKI_EV2)
 274                         if (s->ext_clk) {
 275                                 s->brg_cfg = MAX3107_BRG13_B9600;
 276                                 s->baud_tbl = (struct baud_table *)brg13_ext;
 277                         }
 278         }
 279 }
 280 #endif
 281
 282 static int __devexit max3107_aava_remove(struct spi_device *spi)
 283 {
 284         struct max3107_port *s = dev_get_drvdata(&spi->dev);
 285
 286         /* Remove GPIO chip */
 287         if (gpiochip_remove(&s->chip))
 288                 dev_warn(&spi->dev, "Removing GPIO chip failed\n");
 289
 290         /* Then do the default remove */
 291         return max3107_remove(spi);
 292 }
 293
 294 /* Platform data */
 295 static struct max3107_plat aava_plat_data = {
 296         .loopback               = 0,
 297         .ext_clk                = 1,
 298 /*      .init                   = max3107_aava_init, */
 299         .configure              = max3107_aava_configure,
 300         .hw_suspend             = max3107_hw_susp,
 301         .polled_mode            = 0,
 302         .poll_time              = 0,
 303 };
 304
 305
 306 static int __devinit max3107_probe_aava(struct spi_device *spi)
 307 {
 308         int err = max3107_aava_reset(spi);
 309         if (err < 0)
 310                 return err;
 311         return max3107_probe(spi, &aava_plat_data);
 312 }
 313
 314 /* Spi driver data */
 315 static struct spi_driver max3107_driver = {
 316         .driver = {
 317                 .name           = "aava-max3107",
 318                 .bus            = &spi_bus_type,
 319                 .owner          = THIS_MODULE,
 320         },
 321         .probe          = max3107_probe_aava,
 322         .remove         = __devexit_p(max3107_aava_remove),
 323         .suspend        = max3107_suspend,
 324         .resume         = max3107_resume,
 325 };
 326
 327 /* Driver init function */
 328 static int __init max3107_init(void)
 329 {
 330         return spi_register_driver(&max3107_driver);
 331 }
 332
 333 /* Driver exit function */
 334 static void __exit max3107_exit(void)
 335 {
 336         spi_unregister_driver(&max3107_driver);
 337 }
 338
 339 module_init(max3107_init);
 340 module_exit(max3107_exit);
 341
 342 MODULE_DESCRIPTION("MAX3107 driver");
 343 MODULE_AUTHOR("Aavamobile");
 344 MODULE_ALIAS("spi:aava-max3107");
 345 MODULE_LICENSE("GPL v2");