XW711

The Szenio 1207 is a cheap tablet, based in the A13 chip.

Tricks
If the system hangs up, is possible to do a full power-off by keeping pressed the power button during, at least, 6 seconds.

Components

 * A13 SoC
 * Realtek RTL8188etv USB-based WiFi chip
 * AXP209 Power management
 * Silead GSL1680 capacitive touch screen driver

Booting from a SD card
In order to allow the tablet to boot from a SD card, is imperative to disable the internal NAND in the card's script.bin file. To do so, edit the FEX file and apply this patch:

@@ -12,7 +12,7 @@    pll4_freq = 960 pll6_freq = 720 power_start = 0 -storage_type = 2 +storage_type = 1 [pm_para] standby_mode = 0 @@ -445,7 +445,7 @@    sdc_wp = [mmc2_para] -sdc_used = 1 +sdc_used = 0 sdc_detmode = 3 bus_width = 8 sdc_cmd = port:PC06<3><1><3>

Enabling the WiFi
The Wifi chip is USB-based, and connected to the second USB port, so it's mandatory to enable it. The simplest way of doing this is editing the FEX file and applying this patch:

@@ -505,7 +510,7 @@    [usbc1] usb_used = 1 usb_port_type = 1 usb_detect_type = 0 usb_controller_type = 1 usb_id_gpio = usb_det_vbus_gpio = usb_drv_vbus_gpio = port:power203<1><0> <0> -usb_host_init_state = 0 +usb_host_init_state = 1 [port_pm] restrict_1a = 0

The RTL8188 generic driver (available in kernel 3.4) can be used with this chip. In case it is not detected, apply this patch to drivers/net/wireless/rtl8188eu/os_dep/linux/usb_intf.c:

@@ -185,7 +185,8 @@ static struct usb_device_id rtw_usb_id_tbl[] ={ #endif #ifdef CONFIG_RTL8188E /*=== Realtek demoboard ===*/ {USB_DEVICE(USB_VENDER_ID_REALTEK, 0x8179)},//Default ID           +       {USB_DEVICE(USB_VENDER_ID_REALTEK, 0x0179)},//rtl8188etv ID (szenio 1207 tablet) #endif {}     /* Terminating entry */ };

This patch adds the ID for the ETV model to the list of known devices.