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

   1/*
   2 * Technologic Systems TS-5500 Single Board Computer support
   3 *
   4 * Copyright (C) 2013-2014 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 may be extended to support similar x86-based platforms.
  19 * Actually, the TS-5500 and TS-5400 are supported.
  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/init.h>
  27#include <linux/platform_data/max197.h>
  28#include <linux/platform_device.h>
  29#include <linux/slab.h>
  30
  31/* Product code register */
  32#define TS5500_PRODUCT_CODE_ADDR        0x74
  33#define TS5500_PRODUCT_CODE             0x60    /* TS-5500 product code */
  34#define TS5400_PRODUCT_CODE             0x40    /* TS-5400 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 * @name:       Board model name.
  70 * @id:         Board product ID.
  71 * @sram:       Flag for SRAM option.
  72 * @rs485:      Flag for RS-485 option.
  73 * @adc:        Flag for Analog/Digital converter option.
  74 * @ereset:     Flag for External Reset option.
  75 * @itr:        Flag for Industrial Temperature Range option.
  76 * @jumpers:    Bitfield for jumpers' state.
  77 */
  78struct ts5500_sbc {
  79        const char *name;
  80        int     id;
  81        bool    sram;
  82        bool    rs485;
  83        bool    adc;
  84        bool    ereset;
  85        bool    itr;
  86        u8      jumpers;
  87};
  88
  89/* Board signatures in BIOS shadow RAM */
  90static const struct {
  91        const char * const string;
  92        const ssize_t offset;
  93} ts5500_signatures[] __initconst = {
  94        { "TS-5x00 AMD Elan", 0xb14 },
  95};
  96
  97static int __init ts5500_check_signature(void)
  98{
  99        void __iomem *bios;
 100        int i, ret = -ENODEV;
 101
 102        bios = ioremap(0xf0000, 0x10000);
 103        if (!bios)
 104                return -ENOMEM;
 105
 106        for (i = 0; i < ARRAY_SIZE(ts5500_signatures); i++) {
 107                if (check_signature(bios + ts5500_signatures[i].offset,
 108                                    ts5500_signatures[i].string,
 109                                    strlen(ts5500_signatures[i].string))) {
 110                        ret = 0;
 111                        break;
 112                }
 113        }
 114
 115        iounmap(bios);
 116        return ret;
 117}
 118
 119static int __init ts5500_detect_config(struct ts5500_sbc *sbc)
 120{
 121        u8 tmp;
 122        int ret = 0;
 123
 124        if (!request_region(TS5500_PRODUCT_CODE_ADDR, 4, "ts5500"))
 125                return -EBUSY;
 126
 127        sbc->id = inb(TS5500_PRODUCT_CODE_ADDR);
 128        if (sbc->id == TS5500_PRODUCT_CODE) {
 129                sbc->name = "TS-5500";
 130        } else if (sbc->id == TS5400_PRODUCT_CODE) {
 131                sbc->name = "TS-5400";
 132        } else {
 133                pr_err("ts5500: unknown product code 0x%x\n", sbc->id);
 134                ret = -ENODEV;
 135                goto cleanup;
 136        }
 137
 138        tmp = inb(TS5500_SRAM_RS485_ADC_ADDR);
 139        sbc->sram = tmp & TS5500_SRAM;
 140        sbc->rs485 = tmp & TS5500_RS485;
 141        sbc->adc = tmp & TS5500_ADC;
 142
 143        tmp = inb(TS5500_ERESET_ITR_ADDR);
 144        sbc->ereset = tmp & TS5500_ERESET;
 145        sbc->itr = tmp & TS5500_ITR;
 146
 147        tmp = inb(TS5500_LED_JP_ADDR);
 148        sbc->jumpers = tmp & ~TS5500_LED;
 149
 150cleanup:
 151        release_region(TS5500_PRODUCT_CODE_ADDR, 4);
 152        return ret;
 153}
 154
 155static ssize_t name_show(struct device *dev, struct device_attribute *attr,
 156                char *buf)
 157{
 158        struct ts5500_sbc *sbc = dev_get_drvdata(dev);
 159
 160        return sprintf(buf, "%s\n", sbc->name);
 161}
 162static DEVICE_ATTR_RO(name);
 163
 164static ssize_t id_show(struct device *dev, struct device_attribute *attr,
 165                char *buf)
 166{
 167        struct ts5500_sbc *sbc = dev_get_drvdata(dev);
 168
 169        return sprintf(buf, "0x%.2x\n", sbc->id);
 170}
 171static DEVICE_ATTR_RO(id);
 172
 173static ssize_t jumpers_show(struct device *dev, struct device_attribute *attr,
 174                char *buf)
 175{
 176        struct ts5500_sbc *sbc = dev_get_drvdata(dev);
 177
 178        return sprintf(buf, "0x%.2x\n", sbc->jumpers >> 1);
 179}
 180static DEVICE_ATTR_RO(jumpers);
 181
 182#define TS5500_ATTR_BOOL(_field)                                        \
 183        static ssize_t _field##_show(struct device *dev,                \
 184                        struct device_attribute *attr, char *buf)       \
 185        {                                                               \
 186                struct ts5500_sbc *sbc = dev_get_drvdata(dev);          \
 187                                                                        \
 188                return sprintf(buf, "%d\n", sbc->_field);               \
 189        }                                                               \
 190        static DEVICE_ATTR_RO(_field)
 191
 192TS5500_ATTR_BOOL(sram);
 193TS5500_ATTR_BOOL(rs485);
 194TS5500_ATTR_BOOL(adc);
 195TS5500_ATTR_BOOL(ereset);
 196TS5500_ATTR_BOOL(itr);
 197
 198static struct attribute *ts5500_attributes[] = {
 199        &dev_attr_id.attr,
 200        &dev_attr_name.attr,
 201        &dev_attr_jumpers.attr,
 202        &dev_attr_sram.attr,
 203        &dev_attr_rs485.attr,
 204        &dev_attr_adc.attr,
 205        &dev_attr_ereset.attr,
 206        &dev_attr_itr.attr,
 207        NULL
 208};
 209
 210static const struct attribute_group ts5500_attr_group = {
 211        .attrs = ts5500_attributes,
 212};
 213
 214static struct resource ts5500_dio1_resource[] = {
 215        DEFINE_RES_IRQ_NAMED(7, "DIO1 interrupt"),
 216};
 217
 218static struct platform_device ts5500_dio1_pdev = {
 219        .name = "ts5500-dio1",
 220        .id = -1,
 221        .resource = ts5500_dio1_resource,
 222        .num_resources = 1,
 223};
 224
 225static struct resource ts5500_dio2_resource[] = {
 226        DEFINE_RES_IRQ_NAMED(6, "DIO2 interrupt"),
 227};
 228
 229static struct platform_device ts5500_dio2_pdev = {
 230        .name = "ts5500-dio2",
 231        .id = -1,
 232        .resource = ts5500_dio2_resource,
 233        .num_resources = 1,
 234};
 235
 236static void ts5500_led_set(struct led_classdev *led_cdev,
 237                           enum led_brightness brightness)
 238{
 239        outb(!!brightness, TS5500_LED_JP_ADDR);
 240}
 241
 242static enum led_brightness ts5500_led_get(struct led_classdev *led_cdev)
 243{
 244        return (inb(TS5500_LED_JP_ADDR) & TS5500_LED) ? LED_FULL : LED_OFF;
 245}
 246
 247static struct led_classdev ts5500_led_cdev = {
 248        .name = "ts5500:green:",
 249        .brightness_set = ts5500_led_set,
 250        .brightness_get = ts5500_led_get,
 251};
 252
 253static int ts5500_adc_convert(u8 ctrl)
 254{
 255        u8 lsb, msb;
 256
 257        /* Start conversion (ensure the 3 MSB are set to 0) */
 258        outb(ctrl & 0x1f, TS5500_ADC_CONV_INIT_LSB_ADDR);
 259
 260        /*
 261         * The platform has CPLD logic driving the A/D converter.
 262         * The conversion must complete within 11 microseconds,
 263         * otherwise we have to re-initiate a conversion.
 264         */
 265        udelay(TS5500_ADC_CONV_DELAY);
 266        if (inb(TS5500_ADC_CONV_BUSY_ADDR) & TS5500_ADC_CONV_BUSY)
 267                return -EBUSY;
 268
 269        /* Read the raw data */
 270        lsb = inb(TS5500_ADC_CONV_INIT_LSB_ADDR);
 271        msb = inb(TS5500_ADC_CONV_MSB_ADDR);
 272
 273        return (msb << 8) | lsb;
 274}
 275
 276static struct max197_platform_data ts5500_adc_pdata = {
 277        .convert = ts5500_adc_convert,
 278};
 279
 280static struct platform_device ts5500_adc_pdev = {
 281        .name = "max197",
 282        .id = -1,
 283        .dev = {
 284                .platform_data = &ts5500_adc_pdata,
 285        },
 286};
 287
 288static int __init ts5500_init(void)
 289{
 290        struct platform_device *pdev;
 291        struct ts5500_sbc *sbc;
 292        int err;
 293
 294        /*
 295         * There is no DMI available or PCI bridge subvendor info,
 296         * only the BIOS provides a 16-bit identification call.
 297         * It is safer to find a signature in the BIOS shadow RAM.
 298         */
 299        err = ts5500_check_signature();
 300        if (err)
 301                return err;
 302
 303        pdev = platform_device_register_simple("ts5500", -1, NULL, 0);
 304        if (IS_ERR(pdev))
 305                return PTR_ERR(pdev);
 306
 307        sbc = devm_kzalloc(&pdev->dev, sizeof(struct ts5500_sbc), GFP_KERNEL);
 308        if (!sbc) {
 309                err = -ENOMEM;
 310                goto error;
 311        }
 312
 313        err = ts5500_detect_config(sbc);
 314        if (err)
 315                goto error;
 316
 317        platform_set_drvdata(pdev, sbc);
 318
 319        err = sysfs_create_group(&pdev->dev.kobj, &ts5500_attr_group);
 320        if (err)
 321                goto error;
 322
 323        if (sbc->id == TS5500_PRODUCT_CODE) {
 324                ts5500_dio1_pdev.dev.parent = &pdev->dev;
 325                if (platform_device_register(&ts5500_dio1_pdev))
 326                        dev_warn(&pdev->dev, "DIO1 block registration failed\n");
 327                ts5500_dio2_pdev.dev.parent = &pdev->dev;
 328                if (platform_device_register(&ts5500_dio2_pdev))
 329                        dev_warn(&pdev->dev, "DIO2 block registration failed\n");
 330        }
 331
 332        if (led_classdev_register(&pdev->dev, &ts5500_led_cdev))
 333                dev_warn(&pdev->dev, "LED registration failed\n");
 334
 335        if (sbc->adc) {
 336                ts5500_adc_pdev.dev.parent = &pdev->dev;
 337                if (platform_device_register(&ts5500_adc_pdev))
 338                        dev_warn(&pdev->dev, "ADC registration failed\n");
 339        }
 340
 341        return 0;
 342error:
 343        platform_device_unregister(pdev);
 344        return err;
 345}
 346device_initcall(ts5500_init);
 347