x86/geode/alix2: Supplement driver to include GPIO button support

GPIO 24 is used in reference designs as a soft-reset button, and
the alix2 is no exception.  Add it as a gpio-button.

Use symbolic values to describe BIOS addresses.

Record the model number.

Signed-off-by: Philip A. Prindeville <philipp@redfish-solutions.com>
Acked-by: Ed Wildgoose <kernel@wildgooses.com>
Acked-by: Andres Salomon <dilinger@queued.net>
Cc: Matthew Garrett <mjg@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Link: http://lkml.kernel.org/n/tip-sjp6k1rjksitx1pej0c0qxd1@git.kernel.org
[ tidied up the code a bit ]
Signed-off-by: Ingo Molnar <mingo@elte.hu>

diff --git a/arch/x86/platform/geode/alix.c b/arch/x86/platform/geode/alix.c
index dc5f1d32aced55b27ba532d92b1928e91a59c5b3..90e23e7679a5b9062a34dd266610f1662b426bbb 100644 (file)
--- a/arch/x86/platform/geode/alix.c
+++ b/arch/x86/platform/geode/alix.c
@@ -6,6 +6,7 @@
  *
  * Copyright (C) 2008 Constantin Baranov <const@mimas.ru>
  * Copyright (C) 2011 Ed Wildgoose <kernel@wildgooses.com>
+ *                and Philip Prindeville <philipp@redfish-solutions.com>
  *
  * TODO: There are large similarities with leds-net5501.c
  * by Alessandro Zummo <a.zummo@towertech.it>
@@ -24,14 +25,47 @@
 #include <linux/leds.h>
 #include <linux/platform_device.h>
 #include <linux/gpio.h>
+#include <linux/input.h>
+#include <linux/gpio_keys.h>
+#include <linux/dmi.h>
 
 #include <asm/geode.h>
 
+#define BIOS_SIGNATURE_TINYBIOS                0xf0000
+#define BIOS_SIGNATURE_COREBOOT                0x500
+#define BIOS_REGION_SIZE               0x10000
+
 static bool force = 0;
 module_param(force, bool, 0444);
 /* FIXME: Award bios is not automatically detected as Alix platform */
 MODULE_PARM_DESC(force, "Force detection as ALIX.2/ALIX.3 platform");
 
+static struct gpio_keys_button alix_gpio_buttons[] = {
+       {
+               .code                   = KEY_RESTART,
+               .gpio                   = 24,
+               .active_low             = 1,
+               .desc                   = "Reset button",
+               .type                   = EV_KEY,
+               .wakeup                 = 0,
+               .debounce_interval      = 100,
+               .can_disable            = 0,
+       }
+};
+static struct gpio_keys_platform_data alix_buttons_data = {
+       .buttons                        = alix_gpio_buttons,
+       .nbuttons                       = ARRAY_SIZE(alix_gpio_buttons),
+       .poll_interval                  = 20,
+};
+
+static struct platform_device alix_buttons_dev = {
+       .name                           = "gpio-keys-polled",
+       .id                             = 1,
+       .dev = {
+               .platform_data          = &alix_buttons_data,
+       }
+};
+
 static struct gpio_led alix_leds[] = {
        {
                .name = "alix:1",
@@ -64,17 +98,22 @@ static struct platform_device alix_leds_dev = {
        .dev.platform_data = &alix_leds_data,
 };
 
+static struct __initdata platform_device *alix_devs[] = {
+       &alix_buttons_dev,
+       &alix_leds_dev,
+};
+
 static void __init register_alix(void)
 {
        /* Setup LED control through leds-gpio driver */
-       platform_device_register(&alix_leds_dev);
+       platform_add_devices(alix_devs, ARRAY_SIZE(alix_devs));
 }
 
-static int __init alix_present(unsigned long bios_phys,
+static bool __init alix_present(unsigned long bios_phys,
                                const char *alix_sig,
                                size_t alix_sig_len)
 {
-       const size_t bios_len = 0x00010000;
+       const size_t bios_len = BIOS_REGION_SIZE;
        const char *bios_virt;
        const char *scan_end;
        const char *p;
@@ -84,7 +123,7 @@ static int __init alix_present(unsigned long bios_phys,
                printk(KERN_NOTICE "%s: forced to skip BIOS test, "
                       "assume system is ALIX.2/ALIX.3\n",
                       KBUILD_MODNAME);
-               return 1;
+               return true;
        }
 
        bios_virt = phys_to_virt(bios_phys);
@@ -109,15 +148,33 @@ static int __init alix_present(unsigned long bios_phys,
                        *a = '\0';
 
                tail = p + alix_sig_len;
-               if ((tail[0] == '2' || tail[0] == '3')) {
+               if ((tail[0] == '2' || tail[0] == '3' || tail[0] == '6')) {
                        printk(KERN_INFO
                               "%s: system is recognized as \"%s\"\n",
                               KBUILD_MODNAME, name);
-                       return 1;
+                       return true;
                }
        }
 
-       return 0;
+       return false;
+}
+
+static bool __init alix_present_dmi(void)
+{
+       const char *vendor, *product;
+
+       vendor = dmi_get_system_info(DMI_SYS_VENDOR);
+       if (!vendor || strcmp(vendor, "PC Engines"))
+               return false;
+
+       product = dmi_get_system_info(DMI_PRODUCT_NAME);
+       if (!product || (strcmp(product, "ALIX.2D") && strcmp(product, "ALIX.6")))
+               return false;
+
+       printk(KERN_INFO "%s: system is recognized as \"%s %s\"\n",
+              KBUILD_MODNAME, vendor, product);
+
+       return true;
 }
 
 static int __init alix_init(void)
@@ -128,8 +185,9 @@ static int __init alix_init(void)
        if (!is_geode())
                return 0;
 
-       if (alix_present(0xf0000, tinybios_sig, sizeof(tinybios_sig) - 1) ||
-           alix_present(0x500, coreboot_sig, sizeof(coreboot_sig) - 1))
+       if (alix_present(BIOS_SIGNATURE_TINYBIOS, tinybios_sig, sizeof(tinybios_sig) - 1) ||
+           alix_present(BIOS_SIGNATURE_COREBOOT, coreboot_sig, sizeof(coreboot_sig) - 1) ||
+           alix_present_dmi())
                register_alix();
 
        return 0;