[POWERPC] Add support for briq front panel

This adds the driver for the Briq front panel. This is a cleaned up
version of a driver that has been floating around for some time now,
initially written by Karsten Jeppesen <karsten@jeppesens.com> and
cleaned up by jk and myself.

Signed-off-by: Jeremy Kerr <jk@ozlabs.org>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: Paul Mackerras <paulus@samba.org>

3 files changed, 283 insertions, 0 deletions

diff --git a/drivers/char/Kconfig b/drivers/char/Kconfig
index c40e487d9f5c..11de59ff4229 100644
--- a/drivers/char/Kconfig
+++ b/drivers/char/Kconfig
@@ -495,6 +495,20 @@ config LEGACY_PTY_COUNT
           When not in use, each legacy PTY occupies 12 bytes on 32-bit
           architectures and 24 bytes on 64-bit architectures.
 
+config BRIQ_PANEL
+        tristate 'Total Impact briQ front panel driver'
+        ---help---
+          The briQ is a small footprint CHRP computer with a frontpanel VFD, a
+          tristate led and two switches. It is the size of a CDROM drive.
+
+          If you have such one and want anything showing on the VFD then you
+          must answer Y here.
+
+          To compile this driver as a module, choose M here: the
+          module will be called briq_panel.
+
+          It's safe to say N here.
+
 config PRINTER
         tristate "Parallel printer support"
         depends on PARPORT
diff --git a/drivers/char/Makefile b/drivers/char/Makefile
index 6e0f4469d8bb..7a7ee5721279 100644
--- a/drivers/char/Makefile
+++ b/drivers/char/Makefile
@@ -51,6 +51,7 @@ obj-$(CONFIG_VIOCONS)		+= viocons.o
 obj-$(CONFIG_VIOTAPE)           += viotape.o
 obj-$(CONFIG_HVCS)              += hvcs.o
 obj-$(CONFIG_SGI_MBCS)          += mbcs.o
+obj-$(CONFIG_BRIQ_PANEL)        += briq_panel.o
 
 obj-$(CONFIG_PRINTER)           += lp.o
 obj-$(CONFIG_TIPAR)             += tipar.o
diff --git a/drivers/char/briq_panel.c b/drivers/char/briq_panel.c
new file mode 100644
index 000000000000..a0e5eac5f33a
--- /dev/null
+++ b/drivers/char/briq_panel.c
@@ -0,0 +1,268 @@
+/*
+ * Drivers for the Total Impact PPC based computer "BRIQ"
+ * by Dr. Karsten Jeppesen
+ *
+ */
+
+#include <linux/module.h>
+
+#include <linux/types.h>
+#include <linux/errno.h>
+#include <linux/sched.h>
+#include <linux/tty.h>
+#include <linux/timer.h>
+#include <linux/config.h>
+#include <linux/kernel.h>
+#include <linux/wait.h>
+#include <linux/string.h>
+#include <linux/slab.h>
+#include <linux/ioport.h>
+#include <linux/delay.h>
+#include <linux/miscdevice.h>
+#include <linux/fs.h>
+#include <linux/mm.h>
+#include <linux/init.h>
+
+#include <asm/uaccess.h>
+#include <asm/io.h>
+#include <asm/prom.h>
+
+#define         BRIQ_PANEL_MINOR        156
+#define         BRIQ_PANEL_VFD_IOPORT   0x0390
+#define         BRIQ_PANEL_LED_IOPORT   0x0398
+#define         BRIQ_PANEL_VER          "1.1 (04/20/2002)"
+#define         BRIQ_PANEL_MSG0         "Loading Linux"
+
+static int              vfd_is_open;
+static unsigned char    vfd[40];
+static int              vfd_cursor;
+static unsigned char    ledpb, led;
+
+static void update_vfd(void)
+{
+        int     i;
+
+        /* cursor home */
+        outb(0x02, BRIQ_PANEL_VFD_IOPORT);
+        for (i=0; i<20; i++)
+                outb(vfd[i], BRIQ_PANEL_VFD_IOPORT + 1);
+
+        /* cursor to next line */
+        outb(0xc0, BRIQ_PANEL_VFD_IOPORT);
+        for (i=20; i<40; i++)
+                outb(vfd[i], BRIQ_PANEL_VFD_IOPORT + 1);
+
+}
+
+static void set_led(char state)
+{
+        if (state == 'R')
+                led = 0x01;
+        else if (state == 'G')
+                led = 0x02;
+        else if (state == 'Y')
+                led = 0x03;
+        else if (state == 'X')
+                led = 0x00;
+        outb(led, BRIQ_PANEL_LED_IOPORT);
+}
+
+static int briq_panel_open(struct inode *ino, struct file *filep)
+{
+        /* enforce single access */
+        if (vfd_is_open)
+                return -EBUSY;
+        vfd_is_open = 1;
+
+        return 0;
+}
+
+static int briq_panel_release(struct inode *ino, struct file *filep)
+{
+        if (!vfd_is_open)
+                return -ENODEV;
+
+        vfd_is_open = 0;
+
+        return 0;
+}
+
+static ssize_t briq_panel_read(struct file *file, char *buf, size_t count,
+                         loff_t *ppos)
+{
+        unsigned short c;
+        unsigned char cp;
+
+#if 0   /*  Can't seek (pread) on this device  */
+        if (ppos != &file->f_pos)
+                return -ESPIPE;
+#endif
+
+        if (!vfd_is_open)
+                return -ENODEV;
+
+        c = (inb(BRIQ_PANEL_LED_IOPORT) & 0x000c) | (ledpb & 0x0003);
+        set_led(' ');
+        /* upper button released */
+        if ((!(ledpb & 0x0004)) && (c & 0x0004)) {
+                cp = ' ';
+                ledpb = c;
+                if (copy_to_user(buf, &cp, 1))
+                        return -EFAULT;
+                return 1;
+        }
+        /* lower button released */
+        else if ((!(ledpb & 0x0008)) && (c & 0x0008)) {
+                cp = '\r';
+                ledpb = c;
+                if (copy_to_user(buf, &cp, 1))
+                        return -EFAULT;
+                return 1;
+        } else {
+                ledpb = c;
+                return 0;
+        }
+}
+
+static void scroll_vfd( void )
+{
+        int     i;
+
+        for (i=0; i<20; i++) {
+                vfd[i] = vfd[i+20];
+                vfd[i+20] = ' ';
+        }
+        vfd_cursor = 20;
+}
+
+static ssize_t briq_panel_write(struct file *file, const char *buf, size_t len,
+                          loff_t *ppos)
+{
+        size_t indx = len;
+        int i, esc = 0;
+
+#if 0   /*  Can't seek (pwrite) on this device  */
+        if (ppos != &file->f_pos)
+                return -ESPIPE;
+#endif
+
+        if (!vfd_is_open)
+                return -EBUSY;
+
+        for (;;) {
+                if (!indx)
+                        break;
+                if (esc) {
+                        set_led(*buf);
+                        esc = 0;
+                } else if (*buf == 27) {
+                        esc = 1;
+                } else if (*buf == 12) {
+                        /* do a form feed */
+                        for (i=0; i<40; i++)
+                                vfd[i] = ' ';
+                        vfd_cursor = 0;
+                } else if (*buf == 10) {
+                        if (vfd_cursor < 20)
+                                vfd_cursor = 20;
+                        else if (vfd_cursor < 40)
+                                vfd_cursor = 40;
+                        else if (vfd_cursor < 60)
+                                vfd_cursor = 60;
+                        if (vfd_cursor > 59)
+                                scroll_vfd();
+                } else {
+                        /* just a character */
+                        if (vfd_cursor > 39)
+                                scroll_vfd();
+                        vfd[vfd_cursor++] = *buf;
+                }
+                indx--;
+                buf++;
+        }
+        update_vfd();
+
+        return len;
+}
+
+static struct file_operations briq_panel_fops = {
+        .owner          = THIS_MODULE,
+        .read           = briq_panel_read,
+        .write          = briq_panel_write,
+        .open           = briq_panel_open,
+        .release        = briq_panel_release,
+};
+
+static struct miscdevice briq_panel_miscdev = {
+        BRIQ_PANEL_MINOR,
+        "briq_panel",
+        &briq_panel_fops
+};
+
+static int __init briq_panel_init(void)
+{
+        struct device_node *root = find_path_device("/");
+        char *machine;
+        int i;
+
+        machine = get_property(root, "model", NULL);
+        if (!machine || strncmp(machine, "TotalImpact,BRIQ-1", 18) != 0)
+                return -ENODEV;
+
+        printk(KERN_INFO
+                "briq_panel: v%s Dr. Karsten Jeppesen (kj@totalimpact.com)\n",
+                BRIQ_PANEL_VER);
+
+        if (!request_region(BRIQ_PANEL_VFD_IOPORT, 4, "BRIQ Front Panel"))
+                return -EBUSY;
+
+        if (!request_region(BRIQ_PANEL_LED_IOPORT, 2, "BRIQ Front Panel")) {
+                release_region(BRIQ_PANEL_VFD_IOPORT, 4);
+                return -EBUSY;
+        }
+        ledpb = inb(BRIQ_PANEL_LED_IOPORT) & 0x000c;
+
+        if (misc_register(&briq_panel_miscdev) < 0) {
+                release_region(BRIQ_PANEL_VFD_IOPORT, 4);
+                release_region(BRIQ_PANEL_LED_IOPORT, 2);
+                return -EBUSY;
+        }
+
+        outb(0x38, BRIQ_PANEL_VFD_IOPORT);      /* Function set */
+        outb(0x01, BRIQ_PANEL_VFD_IOPORT);      /* Clear display */
+        outb(0x0c, BRIQ_PANEL_VFD_IOPORT);      /* Display on */
+        outb(0x06, BRIQ_PANEL_VFD_IOPORT);      /* Entry normal */
+        for (i=0; i<40; i++)
+                vfd[i]=' ';
+#ifndef MODULE
+        vfd[0] = 'L';
+        vfd[1] = 'o';
+        vfd[2] = 'a';
+        vfd[3] = 'd';
+        vfd[4] = 'i';
+        vfd[5] = 'n';
+        vfd[6] = 'g';
+        vfd[7] = ' ';
+        vfd[8] = '.';
+        vfd[9] = '.';
+        vfd[10] = '.';
+#endif /* !MODULE */
+
+        update_vfd();
+
+        return 0;
+}
+
+static void __exit briq_panel_exit(void)
+{
+        misc_deregister(&briq_panel_miscdev);
+        release_region(BRIQ_PANEL_VFD_IOPORT, 4);
+        release_region(BRIQ_PANEL_LED_IOPORT, 2);
+}
+
+module_init(briq_panel_init);
+module_exit(briq_panel_exit);
+
+MODULE_LICENSE("GPL");
+MODULE_AUTHOR("Karsten Jeppesen <karsten@jeppesens.com>");
+MODULE_DESCRIPTION("Driver for the Total Impact briQ front panel");