x86: Add TS-5500 platform support

The Technologic Systems TS-5500 is an x86-based (AMD Elan SC520)
single board computer. This driver registers most of its devices
and exposes sysfs attributes for information such as jumpers'
state or presence of some of its options.

This driver currently registers the TS-5500 platform, its
on-board LED, 2 pin blocks (GPIO) and its analog/digital
converter. It can be extended to support other Technologic
Systems products, such as the TS-5600.

Signed-off-by: Vivien Didelot <vivien.didelot@savoirfairelinux.com>
Acked-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Savoir-faire Linux Inc. <kernel@savoirfairelinux.com>
Link: http://lkml.kernel.org/r/1357334294-12760-1-git-send-email-vivien.didelot@savoirfairelinux.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>

2 files changed, 340 insertions, 0 deletions

diff --git a/arch/x86/platform/ts5500/Makefile b/arch/x86/platform/ts5500/Makefile
new file mode 100644
index 000000000000..c54e348c96a7
--- /dev/null
+++ b/arch/x86/platform/ts5500/Makefile
@@ -0,0 +1 @@
+obj-$(CONFIG_TS5500)    += ts5500.o
diff --git a/arch/x86/platform/ts5500/ts5500.c b/arch/x86/platform/ts5500/ts5500.c
new file mode 100644
index 000000000000..39febb214e8c
--- /dev/null
+++ b/arch/x86/platform/ts5500/ts5500.c
@@ -0,0 +1,339 @@
+/*
+ * Technologic Systems TS-5500 Single Board Computer support
+ *
+ * Copyright (C) 2013 Savoir-faire Linux Inc.
+ *      Vivien Didelot <vivien.didelot@savoirfairelinux.com>
+ *
+ * This program is free software; you can redistribute it and/or modify it under
+ * the terms of the GNU General Public License as published by the Free Software
+ * Foundation; either version 2 of the License, or (at your option) any later
+ * version.
+ *
+ *
+ * This driver registers the Technologic Systems TS-5500 Single Board Computer
+ * (SBC) and its devices, and exposes information to userspace such as jumpers'
+ * state or available options. For further information about sysfs entries, see
+ * Documentation/ABI/testing/sysfs-platform-ts5500.
+ *
+ * This code actually supports the TS-5500 platform, but it may be extended to
+ * support similar Technologic Systems x86-based platforms, such as the TS-5600.
+ */
+
+#include <linux/delay.h>
+#include <linux/io.h>
+#include <linux/kernel.h>
+#include <linux/leds.h>
+#include <linux/module.h>
+#include <linux/platform_data/gpio-ts5500.h>
+#include <linux/platform_data/max197.h>
+#include <linux/platform_device.h>
+#include <linux/slab.h>
+
+/* Product code register */
+#define TS5500_PRODUCT_CODE_ADDR        0x74
+#define TS5500_PRODUCT_CODE             0x60    /* TS-5500 product code */
+
+/* SRAM/RS-485/ADC options, and RS-485 RTS/Automatic RS-485 flags register */
+#define TS5500_SRAM_RS485_ADC_ADDR      0x75
+#define TS5500_SRAM                     BIT(0)  /* SRAM option */
+#define TS5500_RS485                    BIT(1)  /* RS-485 option */
+#define TS5500_ADC                      BIT(2)  /* A/D converter option */
+#define TS5500_RS485_RTS                BIT(6)  /* RTS for RS-485 */
+#define TS5500_RS485_AUTO               BIT(7)  /* Automatic RS-485 */
+
+/* External Reset/Industrial Temperature Range options register */
+#define TS5500_ERESET_ITR_ADDR          0x76
+#define TS5500_ERESET                   BIT(0)  /* External Reset option */
+#define TS5500_ITR                      BIT(1)  /* Indust. Temp. Range option */
+
+/* LED/Jumpers register */
+#define TS5500_LED_JP_ADDR              0x77
+#define TS5500_LED                      BIT(0)  /* LED flag */
+#define TS5500_JP1                      BIT(1)  /* Automatic CMOS */
+#define TS5500_JP2                      BIT(2)  /* Enable Serial Console */
+#define TS5500_JP3                      BIT(3)  /* Write Enable Drive A */
+#define TS5500_JP4                      BIT(4)  /* Fast Console (115K baud) */
+#define TS5500_JP5                      BIT(5)  /* User Jumper */
+#define TS5500_JP6                      BIT(6)  /* Console on COM1 (req. JP2) */
+#define TS5500_JP7                      BIT(7)  /* Undocumented (Unused) */
+
+/* A/D Converter registers */
+#define TS5500_ADC_CONV_BUSY_ADDR       0x195   /* Conversion state register */
+#define TS5500_ADC_CONV_BUSY            BIT(0)
+#define TS5500_ADC_CONV_INIT_LSB_ADDR   0x196   /* Start conv. / LSB register */
+#define TS5500_ADC_CONV_MSB_ADDR        0x197   /* MSB register */
+#define TS5500_ADC_CONV_DELAY           12      /* usec */
+
+/**
+ * struct ts5500_sbc - TS-5500 board description
+ * @id:         Board product ID.
+ * @sram:       Flag for SRAM option.
+ * @rs485:      Flag for RS-485 option.
+ * @adc:        Flag for Analog/Digital converter option.
+ * @ereset:     Flag for External Reset option.
+ * @itr:        Flag for Industrial Temperature Range option.
+ * @jumpers:    Bitfield for jumpers' state.
+ */
+struct ts5500_sbc {
+        int     id;
+        bool    sram;
+        bool    rs485;
+        bool    adc;
+        bool    ereset;
+        bool    itr;
+        u8      jumpers;
+};
+
+/* Board signatures in BIOS shadow RAM */
+static const struct {
+        const char * const string;
+        const ssize_t offset;
+} ts5500_signatures[] __initdata = {
+        { "TS-5x00 AMD Elan", 0xb14 },
+};
+
+static int __init ts5500_check_signature(void)
+{
+        void __iomem *bios;
+        int i, ret = -ENODEV;
+
+        bios = ioremap(0xf0000, 0x10000);
+        if (!bios)
+                return -ENOMEM;
+
+        for (i = 0; i < ARRAY_SIZE(ts5500_signatures); i++) {
+                if (check_signature(bios + ts5500_signatures[i].offset,
+                                    ts5500_signatures[i].string,
+                                    strlen(ts5500_signatures[i].string))) {
+                        ret = 0;
+                        break;
+                }
+        }
+
+        iounmap(bios);
+        return ret;
+}
+
+static int __init ts5500_detect_config(struct ts5500_sbc *sbc)
+{
+        u8 tmp;
+        int ret = 0;
+
+        if (!request_region(TS5500_PRODUCT_CODE_ADDR, 4, "ts5500"))
+                return -EBUSY;
+
+        tmp = inb(TS5500_PRODUCT_CODE_ADDR);
+        if (tmp != TS5500_PRODUCT_CODE) {
+                pr_err("This platform is not a TS-5500 (found ID 0x%x)\n", tmp);
+                ret = -ENODEV;
+                goto cleanup;
+        }
+        sbc->id = tmp;
+
+        tmp = inb(TS5500_SRAM_RS485_ADC_ADDR);
+        sbc->sram = tmp & TS5500_SRAM;
+        sbc->rs485 = tmp & TS5500_RS485;
+        sbc->adc = tmp & TS5500_ADC;
+
+        tmp = inb(TS5500_ERESET_ITR_ADDR);
+        sbc->ereset = tmp & TS5500_ERESET;
+        sbc->itr = tmp & TS5500_ITR;
+
+        tmp = inb(TS5500_LED_JP_ADDR);
+        sbc->jumpers = tmp & ~TS5500_LED;
+
+cleanup:
+        release_region(TS5500_PRODUCT_CODE_ADDR, 4);
+        return ret;
+}
+
+static ssize_t ts5500_show_id(struct device *dev,
+                              struct device_attribute *attr, char *buf)
+{
+        struct ts5500_sbc *sbc = dev_get_drvdata(dev);
+
+        return sprintf(buf, "0x%.2x\n", sbc->id);
+}
+
+static ssize_t ts5500_show_jumpers(struct device *dev,
+                                   struct device_attribute *attr,
+                                   char *buf)
+{
+        struct ts5500_sbc *sbc = dev_get_drvdata(dev);
+
+        return sprintf(buf, "0x%.2x\n", sbc->jumpers >> 1);
+}
+
+#define TS5500_SHOW(field)                                      \
+        static ssize_t ts5500_show_##field(struct device *dev,  \
+                        struct device_attribute *attr,          \
+                        char *buf)                              \
+        {                                                       \
+                struct ts5500_sbc *sbc = dev_get_drvdata(dev);  \
+                return sprintf(buf, "%d\n", sbc->field);        \
+        }
+
+TS5500_SHOW(sram)
+TS5500_SHOW(rs485)
+TS5500_SHOW(adc)
+TS5500_SHOW(ereset)
+TS5500_SHOW(itr)
+
+static DEVICE_ATTR(id, S_IRUGO, ts5500_show_id, NULL);
+static DEVICE_ATTR(jumpers, S_IRUGO, ts5500_show_jumpers, NULL);
+static DEVICE_ATTR(sram, S_IRUGO, ts5500_show_sram, NULL);
+static DEVICE_ATTR(rs485, S_IRUGO, ts5500_show_rs485, NULL);
+static DEVICE_ATTR(adc, S_IRUGO, ts5500_show_adc, NULL);
+static DEVICE_ATTR(ereset, S_IRUGO, ts5500_show_ereset, NULL);
+static DEVICE_ATTR(itr, S_IRUGO, ts5500_show_itr, NULL);
+
+static struct attribute *ts5500_attributes[] = {
+        &dev_attr_id.attr,
+        &dev_attr_jumpers.attr,
+        &dev_attr_sram.attr,
+        &dev_attr_rs485.attr,
+        &dev_attr_adc.attr,
+        &dev_attr_ereset.attr,
+        &dev_attr_itr.attr,
+        NULL
+};
+
+static const struct attribute_group ts5500_attr_group = {
+        .attrs = ts5500_attributes,
+};
+
+static struct resource ts5500_dio1_resource[] = {
+        DEFINE_RES_IRQ_NAMED(7, "DIO1 interrupt"),
+};
+
+static struct platform_device ts5500_dio1_pdev = {
+        .name = "ts5500-dio1",
+        .id = -1,
+        .resource = ts5500_dio1_resource,
+        .num_resources = 1,
+};
+
+static struct resource ts5500_dio2_resource[] = {
+        DEFINE_RES_IRQ_NAMED(6, "DIO2 interrupt"),
+};
+
+static struct platform_device ts5500_dio2_pdev = {
+        .name = "ts5500-dio2",
+        .id = -1,
+        .resource = ts5500_dio2_resource,
+        .num_resources = 1,
+};
+
+static void ts5500_led_set(struct led_classdev *led_cdev,
+                           enum led_brightness brightness)
+{
+        outb(!!brightness, TS5500_LED_JP_ADDR);
+}
+
+static enum led_brightness ts5500_led_get(struct led_classdev *led_cdev)
+{
+        return (inb(TS5500_LED_JP_ADDR) & TS5500_LED) ? LED_FULL : LED_OFF;
+}
+
+static struct led_classdev ts5500_led_cdev = {
+        .name = "ts5500:green:",
+        .brightness_set = ts5500_led_set,
+        .brightness_get = ts5500_led_get,
+};
+
+static int ts5500_adc_convert(u8 ctrl)
+{
+        u8 lsb, msb;
+
+        /* Start conversion (ensure the 3 MSB are set to 0) */
+        outb(ctrl & 0x1f, TS5500_ADC_CONV_INIT_LSB_ADDR);
+
+        /*
+         * The platform has CPLD logic driving the A/D converter.
+         * The conversion must complete within 11 microseconds,
+         * otherwise we have to re-initiate a conversion.
+         */
+        udelay(TS5500_ADC_CONV_DELAY);
+        if (inb(TS5500_ADC_CONV_BUSY_ADDR) & TS5500_ADC_CONV_BUSY)
+                return -EBUSY;
+
+        /* Read the raw data */
+        lsb = inb(TS5500_ADC_CONV_INIT_LSB_ADDR);
+        msb = inb(TS5500_ADC_CONV_MSB_ADDR);
+
+        return (msb << 8) | lsb;
+}
+
+static struct max197_platform_data ts5500_adc_pdata = {
+        .convert = ts5500_adc_convert,
+};
+
+static struct platform_device ts5500_adc_pdev = {
+        .name = "max197",
+        .id = -1,
+        .dev = {
+                .platform_data = &ts5500_adc_pdata,
+        },
+};
+
+static int __init ts5500_init(void)
+{
+        struct platform_device *pdev;
+        struct ts5500_sbc *sbc;
+        int err;
+
+        /*
+         * There is no DMI available or PCI bridge subvendor info,
+         * only the BIOS provides a 16-bit identification call.
+         * It is safer to find a signature in the BIOS shadow RAM.
+         */
+        err = ts5500_check_signature();
+        if (err)
+                return err;
+
+        pdev = platform_device_register_simple("ts5500", -1, NULL, 0);
+        if (IS_ERR(pdev))
+                return PTR_ERR(pdev);
+
+        sbc = devm_kzalloc(&pdev->dev, sizeof(struct ts5500_sbc), GFP_KERNEL);
+        if (!sbc) {
+                err = -ENOMEM;
+                goto error;
+        }
+
+        err = ts5500_detect_config(sbc);
+        if (err)
+                goto error;
+
+        platform_set_drvdata(pdev, sbc);
+
+        err = sysfs_create_group(&pdev->dev.kobj, &ts5500_attr_group);
+        if (err)
+                goto error;
+
+        ts5500_dio1_pdev.dev.parent = &pdev->dev;
+        if (platform_device_register(&ts5500_dio1_pdev))
+                dev_warn(&pdev->dev, "DIO1 block registration failed\n");
+        ts5500_dio2_pdev.dev.parent = &pdev->dev;
+        if (platform_device_register(&ts5500_dio2_pdev))
+                dev_warn(&pdev->dev, "DIO2 block registration failed\n");
+
+        if (led_classdev_register(&pdev->dev, &ts5500_led_cdev))
+                dev_warn(&pdev->dev, "LED registration failed\n");
+
+        if (sbc->adc) {
+                ts5500_adc_pdev.dev.parent = &pdev->dev;
+                if (platform_device_register(&ts5500_adc_pdev))
+                        dev_warn(&pdev->dev, "ADC registration failed\n");
+        }
+
+        return 0;
+error:
+        platform_device_unregister(pdev);
+        return err;
+}
+device_initcall(ts5500_init);
+
+MODULE_LICENSE("GPL");
+MODULE_AUTHOR("Savoir-faire Linux Inc. <kernel@savoirfairelinux.com>");
+MODULE_DESCRIPTION("Technologic Systems TS-5500 platform driver");