LXR linux/arch/x86/platform/ts5500/ts5500.c

   1/*
   2 * Technologic Systems TS-5500 Single Board Computer support
   3 *
   4 * Copyright (C) 2013 Savoir-faire Linux Inc.
   5 *      Vivien Didelot <vivien.didelot@savoirfairelinux.com>
   6 *
   7 * This program is free software; you can redistribute it and/or modify it under
   8 * the terms of the GNU General Public License as published by the Free Software
   9 * Foundation; either version 2 of the License, or (at your option) any later
  10 * version.
  11 *
  12 *
  13 * This driver registers the Technologic Systems TS-5500 Single Board Computer
  14 * (SBC) and its devices, and exposes information to userspace such as jumpers'
  15 * state or available options. For further information about sysfs entries, see
  16 * Documentation/ABI/testing/sysfs-platform-ts5500.
  17 *
  18 * This code actually supports the TS-5500 platform, but it may be extended to
  19 * support similar Technologic Systems x86-based platforms, such as the TS-5600.
  20 */
  21
  22#include <linux/delay.h>
  23#include <linux/io.h>
  24#include <linux/kernel.h>
  25#include <linux/leds.h>
  26#include <linux/module.h>
  27#include <linux/platform_data/gpio-ts5500.h>
  28#include <linux/platform_data/max197.h>
  29#include <linux/platform_device.h>
  30#include <linux/slab.h>
  31
  32/* Product code register */
  33#define TS5500_PRODUCT_CODE_ADDR        0x74
  34#define TS5500_PRODUCT_CODE             0x60    /* TS-5500 product code */
  35
  36/* SRAM/RS-485/ADC options, and RS-485 RTS/Automatic RS-485 flags register */
  37#define TS5500_SRAM_RS485_ADC_ADDR      0x75
  38#define TS5500_SRAM                     BIT(0)  /* SRAM option */
  39#define TS5500_RS485                    BIT(1)  /* RS-485 option */
  40#define TS5500_ADC                      BIT(2)  /* A/D converter option */
  41#define TS5500_RS485_RTS                BIT(6)  /* RTS for RS-485 */
  42#define TS5500_RS485_AUTO               BIT(7)  /* Automatic RS-485 */
  43
  44/* External Reset/Industrial Temperature Range options register */
  45#define TS5500_ERESET_ITR_ADDR          0x76
  46#define TS5500_ERESET                   BIT(0)  /* External Reset option */
  47#define TS5500_ITR                      BIT(1)  /* Indust. Temp. Range option */
  48
  49/* LED/Jumpers register */
  50#define TS5500_LED_JP_ADDR              0x77
  51#define TS5500_LED                      BIT(0)  /* LED flag */
  52#define TS5500_JP1                      BIT(1)  /* Automatic CMOS */
  53#define TS5500_JP2                      BIT(2)  /* Enable Serial Console */
  54#define TS5500_JP3                      BIT(3)  /* Write Enable Drive A */
  55#define TS5500_JP4                      BIT(4)  /* Fast Console (115K baud) */
  56#define TS5500_JP5                      BIT(5)  /* User Jumper */
  57#define TS5500_JP6                      BIT(6)  /* Console on COM1 (req. JP2) */
  58#define TS5500_JP7                      BIT(7)  /* Undocumented (Unused) */
  59
  60/* A/D Converter registers */
  61#define TS5500_ADC_CONV_BUSY_ADDR       0x195   /* Conversion state register */
  62#define TS5500_ADC_CONV_BUSY            BIT(0)
  63#define TS5500_ADC_CONV_INIT_LSB_ADDR   0x196   /* Start conv. / LSB register */
  64#define TS5500_ADC_CONV_MSB_ADDR        0x197   /* MSB register */
  65#define TS5500_ADC_CONV_DELAY           12      /* usec */
  66
  67/**
  68 * struct ts5500_sbc - TS-5500 board description
  69 * @id:         Board product ID.
  70 * @sram:       Flag for SRAM option.
  71 * @rs485:      Flag for RS-485 option.
  72 * @adc:        Flag for Analog/Digital converter option.
  73 * @ereset:     Flag for External Reset option.
  74 * @itr:        Flag for Industrial Temperature Range option.
  75 * @jumpers:    Bitfield for jumpers' state.
  76 */
  77struct ts5500_sbc {
  78        int     id;
  79        bool    sram;
  80        bool    rs485;
  81        bool    adc;
  82        bool    ereset;
  83        bool    itr;
  84        u8      jumpers;
  85};
  86
  87/* Board signatures in BIOS shadow RAM */
  88static const struct {
  89        const char * const string;
  90        const ssize_t offset;
  91} ts5500_signatures[] __initdata = {
  92        { "TS-5x00 AMD Elan", 0xb14 },
  93};
  94
  95static int __init ts5500_check_signature(void)
  96{
  97        void __iomem *bios;
  98        int i, ret = -ENODEV;
  99
 100        bios = ioremap(0xf0000, 0x10000);
 101        if (!bios)
 102                return -ENOMEM;
 103
 104        for (i = 0; i < ARRAY_SIZE(ts5500_signatures); i++) {
 105                if (check_signature(bios + ts5500_signatures[i].offset,
 106                                    ts5500_signatures[i].string,
 107                                    strlen(ts5500_signatures[i].string))) {
 108                        ret = 0;
 109                        break;
 110                }
 111        }
 112
 113        iounmap(bios);
 114        return ret;
 115}
 116
 117static int __init ts5500_detect_config(struct ts5500_sbc *sbc)
 118{
 119        u8 tmp;
 120        int ret = 0;
 121
 122        if (!request_region(TS5500_PRODUCT_CODE_ADDR, 4, "ts5500"))
 123                return -EBUSY;
 124
 125        tmp = inb(TS5500_PRODUCT_CODE_ADDR);
 126        if (tmp != TS5500_PRODUCT_CODE) {
 127                pr_err("This platform is not a TS-5500 (found ID 0x%x)\n", tmp);
 128                ret = -ENODEV;
 129                goto cleanup;
 130        }
 131        sbc->id = tmp;
 132
 133        tmp = inb(TS5500_SRAM_RS485_ADC_ADDR);
 134        sbc->sram = tmp & TS5500_SRAM;
 135        sbc->rs485 = tmp & TS5500_RS485;
 136        sbc->adc = tmp & TS5500_ADC;
 137
 138        tmp = inb(TS5500_ERESET_ITR_ADDR);
 139        sbc->ereset = tmp & TS5500_ERESET;
 140        sbc->itr = tmp & TS5500_ITR;
 141
 142        tmp = inb(TS5500_LED_JP_ADDR);
 143        sbc->jumpers = tmp & ~TS5500_LED;
 144
 145cleanup:
 146        release_region(TS5500_PRODUCT_CODE_ADDR, 4);
 147        return ret;
 148}
 149
 150static ssize_t ts5500_show_id(struct device *dev,
 151                              struct device_attribute *attr, char *buf)
 152{
 153        struct ts5500_sbc *sbc = dev_get_drvdata(dev);
 154
 155        return sprintf(buf, "0x%.2x\n", sbc->id);
 156}
 157
 158static ssize_t ts5500_show_jumpers(struct device *dev,
 159                                   struct device_attribute *attr,
 160                                   char *buf)
 161{
 162        struct ts5500_sbc *sbc = dev_get_drvdata(dev);
 163
 164        return sprintf(buf, "0x%.2x\n", sbc->jumpers >> 1);
 165}
 166
 167#define TS5500_SHOW(field)                                      \
 168        static ssize_t ts5500_show_##field(struct device *dev,  \
 169                        struct device_attribute *attr,          \
 170                        char *buf)                              \
 171        {                                                       \
 172                struct ts5500_sbc *sbc = dev_get_drvdata(dev);  \
 173                return sprintf(buf, "%d\n", sbc->field);        \
 174        }
 175
 176TS5500_SHOW(sram)
 177TS5500_SHOW(rs485)
 178TS5500_SHOW(adc)
 179TS5500_SHOW(ereset)
 180TS5500_SHOW(itr)
 181
 182static DEVICE_ATTR(id, S_IRUGO, ts5500_show_id, NULL);
 183static DEVICE_ATTR(jumpers, S_IRUGO, ts5500_show_jumpers, NULL);
 184static DEVICE_ATTR(sram, S_IRUGO, ts5500_show_sram, NULL);
 185static DEVICE_ATTR(rs485, S_IRUGO, ts5500_show_rs485, NULL);
 186static DEVICE_ATTR(adc, S_IRUGO, ts5500_show_adc, NULL);
 187static DEVICE_ATTR(ereset, S_IRUGO, ts5500_show_ereset, NULL);
 188static DEVICE_ATTR(itr, S_IRUGO, ts5500_show_itr, NULL);
 189
 190static struct attribute *ts5500_attributes[] = {
 191        &dev_attr_id.attr,
 192        &dev_attr_jumpers.attr,
 193        &dev_attr_sram.attr,
 194        &dev_attr_rs485.attr,
 195        &dev_attr_adc.attr,
 196        &dev_attr_ereset.attr,
 197        &dev_attr_itr.attr,
 198        NULL
 199};
 200
 201static const struct attribute_group ts5500_attr_group = {
 202        .attrs = ts5500_attributes,
 203};
 204
 205static struct resource ts5500_dio1_resource[] = {
 206        DEFINE_RES_IRQ_NAMED(7, "DIO1 interrupt"),
 207};
 208
 209static struct platform_device ts5500_dio1_pdev = {
 210        .name = "ts5500-dio1",
 211        .id = -1,
 212        .resource = ts5500_dio1_resource,
 213        .num_resources = 1,
 214};
 215
 216static struct resource ts5500_dio2_resource[] = {
 217        DEFINE_RES_IRQ_NAMED(6, "DIO2 interrupt"),
 218};
 219
 220static struct platform_device ts5500_dio2_pdev = {
 221        .name = "ts5500-dio2",
 222        .id = -1,
 223        .resource = ts5500_dio2_resource,
 224        .num_resources = 1,
 225};
 226
 227static void ts5500_led_set(struct led_classdev *led_cdev,
 228                           enum led_brightness brightness)
 229{
 230        outb(!!brightness, TS5500_LED_JP_ADDR);
 231}
 232
 233static enum led_brightness ts5500_led_get(struct led_classdev *led_cdev)
 234{
 235        return (inb(TS5500_LED_JP_ADDR) & TS5500_LED) ? LED_FULL : LED_OFF;
 236}
 237
 238static struct led_classdev ts5500_led_cdev = {
 239        .name = "ts5500:green:",
 240        .brightness_set = ts5500_led_set,
 241        .brightness_get = ts5500_led_get,
 242};
 243
 244static int ts5500_adc_convert(u8 ctrl)
 245{
 246        u8 lsb, msb;
 247
 248        /* Start conversion (ensure the 3 MSB are set to 0) */
 249        outb(ctrl & 0x1f, TS5500_ADC_CONV_INIT_LSB_ADDR);
 250
 251        /*
 252         * The platform has CPLD logic driving the A/D converter.
 253         * The conversion must complete within 11 microseconds,
 254         * otherwise we have to re-initiate a conversion.
 255         */
 256        udelay(TS5500_ADC_CONV_DELAY);
 257        if (inb(TS5500_ADC_CONV_BUSY_ADDR) & TS5500_ADC_CONV_BUSY)
 258                return -EBUSY;
 259
 260        /* Read the raw data */
 261        lsb = inb(TS5500_ADC_CONV_INIT_LSB_ADDR);
 262        msb = inb(TS5500_ADC_CONV_MSB_ADDR);
 263
 264        return (msb << 8) | lsb;
 265}
 266
 267static struct max197_platform_data ts5500_adc_pdata = {
 268        .convert = ts5500_adc_convert,
 269};
 270
 271static struct platform_device ts5500_adc_pdev = {
 272        .name = "max197",
 273        .id = -1,
 274        .dev = {
 275                .platform_data = &ts5500_adc_pdata,
 276        },
 277};
 278
 279static int __init ts5500_init(void)
 280{
 281        struct platform_device *pdev;
 282        struct ts5500_sbc *sbc;
 283        int err;
 284
 285        /*
 286         * There is no DMI available or PCI bridge subvendor info,
 287         * only the BIOS provides a 16-bit identification call.
 288         * It is safer to find a signature in the BIOS shadow RAM.
 289         */
 290        err = ts5500_check_signature();
 291        if (err)
 292                return err;
 293
 294        pdev = platform_device_register_simple("ts5500", -1, NULL, 0);
 295        if (IS_ERR(pdev))
 296                return PTR_ERR(pdev);
 297
 298        sbc = devm_kzalloc(&pdev->dev, sizeof(struct ts5500_sbc), GFP_KERNEL);
 299        if (!sbc) {
 300                err = -ENOMEM;
 301                goto error;
 302        }
 303
 304        err = ts5500_detect_config(sbc);
 305        if (err)
 306                goto error;
 307
 308        platform_set_drvdata(pdev, sbc);
 309
 310        err = sysfs_create_group(&pdev->dev.kobj, &ts5500_attr_group);
 311        if (err)
 312                goto error;
 313
 314        ts5500_dio1_pdev.dev.parent = &pdev->dev;
 315        if (platform_device_register(&ts5500_dio1_pdev))
 316                dev_warn(&pdev->dev, "DIO1 block registration failed\n");
 317        ts5500_dio2_pdev.dev.parent = &pdev->dev;
 318        if (platform_device_register(&ts5500_dio2_pdev))
 319                dev_warn(&pdev->dev, "DIO2 block registration failed\n");
 320
 321        if (led_classdev_register(&pdev->dev, &ts5500_led_cdev))
 322                dev_warn(&pdev->dev, "LED registration failed\n");
 323
 324        if (sbc->adc) {
 325                ts5500_adc_pdev.dev.parent = &pdev->dev;
 326                if (platform_device_register(&ts5500_adc_pdev))
 327                        dev_warn(&pdev->dev, "ADC registration failed\n");
 328        }
 329
 330        return 0;
 331error:
 332        platform_device_unregister(pdev);
 333        return err;
 334}
 335device_initcall(ts5500_init);
 336
 337MODULE_LICENSE("GPL");
 338MODULE_AUTHOR("Savoir-faire Linux Inc. <kernel@savoirfairelinux.com>");
 339MODULE_DESCRIPTION("Technologic Systems TS-5500 platform driver");
 340