diff options
Diffstat (limited to 'arch/x86/platform/geode/alix.c')
| -rw-r--r-- | arch/x86/platform/geode/alix.c | 195 |
1 files changed, 195 insertions, 0 deletions
diff --git a/arch/x86/platform/geode/alix.c b/arch/x86/platform/geode/alix.c new file mode 100644 index 000000000..c33f744b5 --- /dev/null +++ b/arch/x86/platform/geode/alix.c @@ -0,0 +1,195 @@ +// SPDX-License-Identifier: GPL-2.0-only +/* + * System Specific setup for PCEngines ALIX. + * At the moment this means setup of GPIO control of LEDs + * on Alix.2/3/6 boards. + * + * 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> + * In the future leds-net5501.c should be migrated over to platform + */ + +#include <linux/kernel.h> +#include <linux/init.h> +#include <linux/io.h> +#include <linux/string.h> +#include <linux/moduleparam.h> +#include <linux/leds.h> +#include <linux/platform_device.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 + +/* + * This driver is not modular, but to keep back compatibility + * with existing use cases, continuing with module_param is + * the easiest way forward. + */ +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", + .gpio = 6, + .default_trigger = "default-on", + .active_low = 1, + }, + { + .name = "alix:2", + .gpio = 25, + .default_trigger = "default-off", + .active_low = 1, + }, + { + .name = "alix:3", + .gpio = 27, + .default_trigger = "default-off", + .active_low = 1, + }, +}; + +static struct gpio_led_platform_data alix_leds_data = { + .num_leds = ARRAY_SIZE(alix_leds), + .leds = alix_leds, +}; + +static struct platform_device alix_leds_dev = { + .name = "leds-gpio", + .id = -1, + .dev.platform_data = &alix_leds_data, +}; + +static struct platform_device *alix_devs[] __initdata = { + &alix_buttons_dev, + &alix_leds_dev, +}; + +static void __init register_alix(void) +{ + /* Setup LED control through leds-gpio driver */ + platform_add_devices(alix_devs, ARRAY_SIZE(alix_devs)); +} + +static bool __init alix_present(unsigned long bios_phys, + const char *alix_sig, + size_t alix_sig_len) +{ + const size_t bios_len = BIOS_REGION_SIZE; + const char *bios_virt; + const char *scan_end; + const char *p; + char name[64]; + + if (force) { + printk(KERN_NOTICE "%s: forced to skip BIOS test, " + "assume system is ALIX.2/ALIX.3\n", + KBUILD_MODNAME); + return true; + } + + bios_virt = phys_to_virt(bios_phys); + scan_end = bios_virt + bios_len - (alix_sig_len + 2); + for (p = bios_virt; p < scan_end; p++) { + const char *tail; + char *a; + + if (memcmp(p, alix_sig, alix_sig_len) != 0) + continue; + + memcpy(name, p, sizeof(name)); + + /* remove the first \0 character from string */ + a = strchr(name, '\0'); + if (a) + *a = ' '; + + /* cut the string at a newline */ + a = strchr(name, '\r'); + if (a) + *a = '\0'; + + tail = p + alix_sig_len; + if ((tail[0] == '2' || tail[0] == '3' || tail[0] == '6')) { + printk(KERN_INFO + "%s: system is recognized as \"%s\"\n", + KBUILD_MODNAME, name); + return true; + } + } + + 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) +{ + const char tinybios_sig[] = "PC Engines ALIX."; + const char coreboot_sig[] = "PC Engines\0ALIX."; + + if (!is_geode()) + return 0; + + 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; +} +device_initcall(alix_init); |