1 files changed, 30 insertions, 0 deletions

diff --git a/arch/arm/mach-orion/ts209-setup.c b/arch/arm/mach-orion/ts209-setup.c
index 34f88ac24ac8..e3e930efd155 100644
--- a/arch/arm/mach-orion/ts209-setup.c
+++ b/arch/arm/mach-orion/ts209-setup.c
@@ -20,6 +20,7 @@
 #include <linux/gpio_keys.h>
 #include <linux/input.h>
 #include <linux/i2c.h>
+#include <linux/serial_reg.h>
 #include <asm/mach-types.h>
 #include <asm/gpio.h>
 #include <asm/mach/arch.h>
@@ -239,6 +240,32 @@ static struct platform_device *qnap_ts209_devices[] __initdata = {
         &qnap_ts209_button_device,
 };
 
+/*
+ * QNAP TS-[12]09 specific power off method via UART1-attached PIC
+ */
+
+#define UART1_REG(x)  (UART1_BASE + ((UART_##x) << 2))
+
+static void qnap_ts209_power_off(void)
+{
+        /* 19200 baud divisor */
+        const unsigned divisor = ((ORION_TCLK + (8 * 19200)) / (16 * 19200));
+
+        pr_info("%s: triggering power-off...\n", __func__);
+
+        /* hijack uart1 and reset into sane state (19200,8n1) */
+        orion_write(UART1_REG(LCR), 0x83);
+        orion_write(UART1_REG(DLL), divisor & 0xff);
+        orion_write(UART1_REG(DLM), (divisor >> 8) & 0xff);
+        orion_write(UART1_REG(LCR), 0x03);
+        orion_write(UART1_REG(IER), 0x00);
+        orion_write(UART1_REG(FCR), 0x00);
+        orion_write(UART1_REG(MCR), 0x00);
+
+        /* send the power-off command 'A' to PIC */
+        orion_write(UART1_REG(TX), 'A');
+}
+
 static void __init qnap_ts209_init(void)
 {
         /*
@@ -287,6 +314,9 @@ static void __init qnap_ts209_init(void)
         orion_write(MPP_16_19_CTRL, 0x5500);
         orion_gpio_set_valid_pins(0x3cc0fff);
 
+        /* register ts209 specific power-off method */
+        pm_power_off = qnap_ts209_power_off;
+
         platform_add_devices(qnap_ts209_devices,
                                 ARRAY_SIZE(qnap_ts209_devices));
         i2c_register_board_info(0, &qnap_ts209_i2c_rtc, 1);