Sansa Connect: Initial libertas WiFi driver port

Import non-free firmware image from linux-firmware package.

Firmware loading works but is disabled at compile time because just
loading firmware without configuring device results in higher power
consumption without any benefit to end user.

Change-Id: I8fd252c49385ede1ea4e0f9b1e29adeb331ab8ae

firmware/target/arm/tms320dm320/sansa-connect/avr-sansaconnect.c

@@ -75,7 +75,7 @@
 #define CMD_WHEEL_EN            0xD0
 #define CMD_SET_INTCHRG         0xD1
 #define CMD_GET_INTCHRG         0xD2
-#define CMD_UNKNOWN_D3          0xD3
+#define CMD_WIFI_PD             0xD3
 #define CMD_UNKNOWN_D4          0xD4
 #define CMD_UNKNOWN_D5          0xD5
 #define CMD_UNKNOWN_D6          0xD6
@@ -315,7 +315,7 @@ static size_t avr_command_data_size(uint8_t opcode)
         case CMD_WHEEL_EN:            return 1;
         case CMD_SET_INTCHRG:         return 1;
         case CMD_GET_INTCHRG:         return 1;
-        case CMD_UNKNOWN_D3:          return 1;
+        case CMD_WIFI_PD:             return 1;
         case CMD_UNKNOWN_D4:          return 1;
         case CMD_UNKNOWN_D5:          return 2;
         case CMD_UNKNOWN_D6:          return 2;
@@ -536,6 +536,12 @@ void avr_hid_enable_charger(void)
     avr_execute_command(CMD_SET_INTCHRG, &enable, sizeof(enable));
 }
 
+void avr_hid_wifi_pd(int high)
+{
+    uint8_t state = high ? 0x01 : 0x00;
+    avr_execute_command(CMD_WIFI_PD, &state, sizeof(state));
+}
+
 static void avr_hid_lcm_power(uint8_t parameter)
 {
     avr_execute_command(CMD_LCM_POWER, &parameter, sizeof(parameter));

firmware/target/arm/tms320dm320/sansa-connect/avr-sansaconnect.h

@@ -28,6 +28,8 @@ void avr_hid_init(void);
 
 void avr_hid_enable_charger(void);
 
+void avr_hid_wifi_pd(int high);
+
 void avr_hid_lcm_sleep(void);
 void avr_hid_lcm_wake(void);
 void avr_hid_lcm_power_on(void);

firmware/target/arm/tms320dm320/sansa-connect/wifi-sansaconnect.c

@@ -0,0 +1,130 @@
+/***************************************************************************
+*             __________               __   ___.
+*   Open      \______   \ ____   ____ |  | _\_ |__   _______  ___
+*   Source     |       _//  _ \_/ ___\|  |/ /| __ \ /  _ \  \/  /
+*   Jukebox    |    |   (  <_> )  \___|    < | \_\ (  <_> > <  <
+*   Firmware   |____|_  /\____/ \___  >__|_ \|___  /\____/__/\_ \
+*                     \/            \/     \/    \/            \/
+* $Id$
+*
+* Copyright (C) 2021 by Tomasz Moń
+*
+* This program is free software; you can redistribute it and/or
+* modify it under the terms of the GNU General Public License
+* as published by the Free Software Foundation; either version 2
+* of the License, or (at your option) any later version.
+*
+* This software is distributed on an "AS IS" basis, WITHOUT WARRANTY OF ANY
+* KIND, either express or implied.
+*
+****************************************************************************/
+
+#include "kernel.h"
+#include "system.h"
+#include "spi.h"
+#include "avr-sansaconnect.h"
+#include "libertas/if_spi_drv.h"
+
+#define IO_SERIAL0_XMIT         (0x100)
+
+void libertas_spi_init(void)
+{
+    IO_GIO_DIR0 &= ~((1 << 4) /* CS */ | (1 << 3) /* reset */);
+    libertas_spi_reset(1);
+    libertas_spi_cs(1);
+
+    /* Enable the clock */
+    bitset16(&IO_CLK_MOD2, CLK_MOD2_SIF0);
+
+    /* Disable transmitter */
+    IO_SERIAL0_TX_ENABLE = 0x0001;
+
+    /* SELSDEN = 0, SLVEN = 0, SIOCLR = 0, SCLKM = 1, MSB = 1, MSSEL = 0,
+     * RATE = 2 -> 15MHz
+     */
+    IO_SERIAL0_MODE = 0x0601;
+
+    /* Disable the clock */
+    bitclr16(&IO_CLK_MOD2, CLK_MOD2_SIF0);
+
+    /* Make sure the SPI clock is not inverted */
+    bitclr16(&IO_CLK_INV, CLK_INV_SIF0);
+}
+
+void libertas_spi_reset(int high)
+{
+    if (high)
+    {
+        IO_GIO_BITSET0 = (1 << 3);
+    }
+    else
+    {
+        IO_GIO_BITCLR0 = (1 << 3);
+    }
+}
+
+void libertas_spi_pd(int high)
+{
+    avr_hid_wifi_pd(high);
+}
+
+void libertas_spi_cs(int high)
+{
+    if (high)
+    {
+        IO_GIO_BITSET0 = (1 << 4);
+    }
+    else
+    {
+        IO_GIO_BITCLR0 = (1 << 4);
+    }
+}
+
+void libertas_spi_tx(const uint8_t *buf, int len)
+{
+    /* Enable the clock */
+    bitset16(&IO_CLK_MOD2, CLK_MOD2_SIF0);
+    IO_SERIAL0_TX_ENABLE = 0x0001;
+
+    while (len > 0)
+    {
+        IO_SERIAL0_TX_DATA = *(buf + 1);
+        while (IO_SERIAL0_RX_DATA & IO_SERIAL0_XMIT) {};
+        IO_SERIAL0_TX_DATA = *buf;
+        while (IO_SERIAL0_RX_DATA & IO_SERIAL0_XMIT) {};
+
+        buf += 2;
+        len -= 2;
+    }
+
+    IO_SERIAL0_TX_ENABLE = 0x0000;
+
+    /* Disable the clock */
+    bitclr16(&IO_CLK_MOD2, CLK_MOD2_SIF0);
+}
+
+void libertas_spi_rx(uint8_t *buf, int len)
+{
+    /* Enable the clock */
+    bitset16(&IO_CLK_MOD2, CLK_MOD2_SIF0);
+    IO_SERIAL0_TX_ENABLE = 0x0001;
+
+    while (len > 0)
+    {
+        uint16_t data;
+        IO_SERIAL0_TX_DATA = 0;
+        while ((data = IO_SERIAL0_RX_DATA) & IO_SERIAL0_XMIT) {};
+        *(buf + 1) = data & 0xFF;
+        IO_SERIAL0_TX_DATA = 0;
+        while ((data = IO_SERIAL0_RX_DATA) & IO_SERIAL0_XMIT) {};
+        *buf = data & 0xFF;
+
+        buf += 2;
+        len -= 2;
+    }
+
+    IO_SERIAL0_TX_ENABLE = 0x0000;
+
+    /* Disable the clock */
+    bitclr16(&IO_CLK_MOD2, CLK_MOD2_SIF0);
+}

firmware/target/arm/tms320dm320/system-dm320.c

@@ -369,9 +369,11 @@ void system_init(void)
 #endif
 
 #ifdef SANSA_CONNECT
+#ifndef HAVE_WIFI
     /* keep WIFI CS and reset high to save power */
     IO_GIO_DIR0 &= ~((1 << 4) /* CS */ | (1 << 3) /* reset */);
     IO_GIO_BITSET0 = (1 << 4) | (1 << 3);
+#endif
 
     i2c_init();
     avr_hid_init();