baremetal: Add USB HID gamepads example for MSP430f5529 chip

This example demonstrates how to create the USB HID device
on MSP430f5529 chip (based on MSP430 architecture) using the
different toolchains (IAR EW, GCC).

Change-Id: Ic4d6a17d3e75e7ccb9b1f3eeaaef9abdf2da896b
Reviewed-by: Christian Kandeler <christian.kandeler@qt.io>

1 files changed, 317 insertions, 0 deletions

diff --git a/examples/baremetal/msp430f5529/nes-gamepads/usb.c b/examples/baremetal/msp430f5529/nes-gamepads/usb.c
new file mode 100644
index 000000000..2a6485803
--- /dev/null
+++ b/examples/baremetal/msp430f5529/nes-gamepads/usb.c
@@ -0,0 +1,317 @@
+/****************************************************************************
+**
+** Copyright (C) 2019 Denis Shienkov <denis.shienkov@gmail.com>
+** Contact: https://www.qt.io/licensing/
+**
+** This file is part of the examples of Qbs.
+**
+** $QT_BEGIN_LICENSE:BSD$
+** Commercial License Usage
+** Licensees holding valid commercial Qt licenses may use this file in
+** accordance with the commercial license agreement provided with the
+** Software or, alternatively, in accordance with the terms contained in
+** a written agreement between you and The Qt Company. For licensing terms
+** and conditions see https://www.qt.io/terms-conditions. For further
+** information use the contact form at https://www.qt.io/contact-us.
+**
+** BSD License Usage
+** Alternatively, you may use this file under the terms of the BSD license
+** as follows:
+**
+** "Redistribution and use in source and binary forms, with or without
+** modification, are permitted provided that the following conditions are
+** met:
+**   * Redistributions of source code must retain the above copyright
+**     notice, this list of conditions and the following disclaimer.
+**   * Redistributions in binary form must reproduce the above copyright
+**     notice, this list of conditions and the following disclaimer in
+**     the documentation and/or other materials provided with the
+**     distribution.
+**   * Neither the name of The Qt Company Ltd nor the names of its
+**     contributors may be used to endorse or promote products derived
+**     from this software without specific prior written permission.
+**
+**
+** THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+** "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+** LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+** A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+** OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+** SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+** LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+** DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+** THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+** (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+** OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE."
+**
+** $QT_END_LICENSE$
+**
+****************************************************************************/
+
+#include "gpio.h"
+#include "hid.h"
+#include "hwdefs.h"
+#include "ucs.h"
+#include "usb.h"
+
+static uint16_t usb_khz_freq_get(void)
+{
+    uint16_t freq = 0;
+    const uint8_t selm_curr = (UCSCTL4_L & SELM_7);
+    if (selm_curr <= 4) {
+        uint16_t fll_ref_freq = 33; // It is 32.768 kHz.
+        if ((UCSCTL3_L & SELREF_7) >= 0x50)
+            fll_ref_freq = (4.0) * 1000;
+
+        uint16_t flln_curr = (UCSCTL2 & 0x03FF) + 1;
+        if (selm_curr == SELM_3) {
+            uint16_t flld_curr = (UCSCTL2 & FLLD_7);
+            flld_curr >>= 12;
+            flln_curr <<= flld_curr;
+        }
+
+        const uint8_t fll_ref_div = (UCSCTL3_L & FLLREFDIV_7);
+        if (fll_ref_div == 0)
+            freq = flln_curr * (fll_ref_freq / 1);
+        else if (fll_ref_div == 1)
+            freq = flln_curr * (fll_ref_freq / 2);
+        else if (fll_ref_div == 2)
+            freq = flln_curr * (fll_ref_freq / 4);
+        else if (fll_ref_div == 3)
+            freq = flln_curr * (fll_ref_freq / 8);
+        else if (fll_ref_div == 4)
+            freq = flln_curr * (fll_ref_freq / 12);
+        else if (fll_ref_div == 5)
+            freq = flln_curr * (fll_ref_freq / 16);
+    } else {
+        freq = (4.0) * 1000;
+    }
+    return freq >> (UCSCTL5_L & DIVM_7);
+}
+
+static uint16_t usb_delay_250us_get(void)
+{
+    const uint16_t mclk_freq = usb_khz_freq_get();
+    const uint16_t delay_250us = ((mclk_freq >> 6) | (mclk_freq >> 7)
+                                  | (mclk_freq >> 9));
+    return delay_250us;
+}
+
+static void usb_cfg_access_allow(bool allow)
+{
+    enum { ALLOW_KEY = 0x9628, DENIED_KEY = 0x9600 };
+    USBKEYPID = allow ? ALLOW_KEY : DENIED_KEY;
+}
+
+static bool usb_pll_enable(void)
+{
+    if (!(USBPWRCTL & USBBGVBV))
+        return false;
+
+    if ((USBCNF & USB_EN) && (USBPLLCTL & UPLLEN))
+        return true;
+
+    gpio_pins_set_as_pf_out(GPIO_PORT_P5, GPIO_PIN2);
+    gpio_pins_set_as_pf_out(GPIO_PORT_P5, GPIO_PIN3);
+
+    usb_cfg_access_allow(true);
+
+    if (!ucs_xt2_blocking_turn_on(XT2DRIVE_0, 50000))
+        return false;
+
+    USBPLLDIVB = USBPLL_SETCLK_4_0;
+    USBPLLCTL = UPFDEN | UPLLEN;
+
+    const uint16_t delay_250us = usb_delay_250us_get();
+    uint8_t j = 0;
+    do {
+        USBPLLIR = 0;
+        for (uint8_t k = 0; k < 2; ++k) {
+            for (uint16_t i = 0; i < delay_250us; ++i) {
+                __no_operation();
+            }
+        }
+
+        if (j++ > 10) {
+            usb_cfg_access_allow(false);
+            return false;
+        }
+    } while (USBPLLIR != 0);
+
+    USBCNF |= USB_EN;
+    usb_cfg_access_allow(false);
+    return true;
+}
+
+static void usb_reset(void)
+{
+    usb_cfg_access_allow(true);
+
+    hid_ep0_enumerated_set(false);
+
+    USBCTL = 0;
+    USBFUNADR = 0;
+    USBOEPIE = 0;
+    USBIEPIE = 0;
+
+    hid_ep0_init();
+    hid_ep1_init();
+
+    USBCTL = FEN;
+    USBIFG = 0;
+    USBIE = SETUPIE | RSTRIE | SUSRIE;
+    usb_cfg_access_allow(false);
+}
+
+static void usb_connect(void)
+{
+    usb_cfg_access_allow(true);
+    USBCNF |= PUR_EN;
+    USBPWRCTL |= VBOFFIE;
+    usb_cfg_access_allow(false);
+}
+
+static void usb_pwr_vbus_wait(void)
+{
+    const uint16_t delay_250us = usb_delay_250us_get();
+    for (uint8_t j = 0; j < 4; ++j) {
+        for (uint16_t i = 0; i < delay_250us; ++i) {
+            __no_operation();
+        }
+    }
+}
+
+static void usb_pwr_vbus_on_handler(void)
+{
+    usb_pwr_vbus_wait();
+
+    if (USBPWRCTL & USBBGVBV) {
+        usb_cfg_access_allow(true);
+        USBPWRCTL |= VBOFFIE;
+        USBPWRCTL &= ~ (VBONIFG + VBOFFIFG);
+        usb_cfg_access_allow(false);
+    }
+}
+
+static void usb_pwr_vbus_off_handler(void)
+{
+    usb_pwr_vbus_wait();
+
+    if (!(USBPWRCTL & USBBGVBV)) {
+        usb_cfg_access_allow(true);
+        USBCNF = 0;
+        USBPLLCTL &= ~UPLLEN;
+        USBPWRCTL &= ~(VBOFFIE + VBOFFIFG + SLDOEN);
+        usb_cfg_access_allow(false);
+    }
+}
+
+void usb_suspend(void)
+{
+    usb_cfg_access_allow(true);
+    USBCTL |= FRSTE;
+    USBIFG &= ~SUSRIFG;
+    USBPLLCTL &= ~UPLLEN;
+    ucs_xt2_turn_off();
+    USBIE = RESRIE;
+    usb_cfg_access_allow(false);
+}
+
+void usb_resume(void)
+{
+    usb_pll_enable();
+    USBIFG &= ~(RESRIFG | SUSRIFG);
+    USBIE = SETUPIE | RSTRIE | SUSRIE;
+}
+
+void usb_init(void)
+{
+    const uint16_t gie_backup  = (__get_SR_register() & GIE);
+
+    usb_cfg_access_allow(true);
+    USBPHYCTL = PUSEL;
+    USBPWRCTL = VUSBEN | SLDOAON;
+
+    const uint16_t delay_250us = usb_delay_250us_get();
+    for (uint8_t j = 0; j < 20; ++j) {
+        for (uint16_t i = 0; i < delay_250us; ++i) {
+            __no_operation();
+        }
+    }
+
+    USBPWRCTL |= VBONIE;
+    usb_cfg_access_allow(false);
+
+    __bis_SR_register(gie_backup);
+
+    if (USBPWRCTL & USBBGVBV) {
+        if (usb_pll_enable()) {
+            usb_reset();
+            usb_connect();
+        }
+    }
+}
+
+void usb_task(void)
+{
+    hid_ep1_task();
+}
+
+INTERRUPT(usb_ubm_isr, USB_UBM_VECTOR)
+{
+    bool wake_up = false;
+
+    if (USBIFG & SETUPIFG) {
+        hid_ep0_setup_handler();
+        USBIFG &= ~SETUPIFG;
+    }
+
+    switch (__even_in_range(USBVECINT & 0x3F, USBVECINT_OUTPUT_ENDPOINT7)) {
+    case USBVECINT_PWR_DROP:
+        __no_operation();
+        break;
+    case USBVECINT_PLL_RANGE:
+        wake_up = true;
+        break;
+    case USBVECINT_PWR_VBUSOn:
+        usb_pwr_vbus_on_handler();
+        if (usb_pll_enable()) {
+            usb_reset();
+            usb_connect();
+        }
+        wake_up = true;
+        break;
+    case USBVECINT_PWR_VBUSOff:
+        usb_pwr_vbus_off_handler();
+        ucs_xt2_turn_off();
+        wake_up = true;
+        break;
+    case USBVECINT_INPUT_ENDPOINT0:
+        hid_ep0_in_handler();
+        break;
+    case USBVECINT_RSTR:
+        usb_reset();
+        wake_up = true;
+        break;
+    case USBVECINT_SUSR:
+        usb_suspend();
+        wake_up = true;
+        break;
+    case USBVECINT_RESR:
+        usb_resume();
+        wake_up = true;
+        break;
+    case USBVECINT_SETUP_PACKET_RECEIVED:
+        hid_ep0_in_nak();
+        hid_ep0_out_nak();
+        hid_ep0_setup_handler();
+        break;
+    default:
+        break;
+    }
+
+    if (wake_up) {
+        __bic_SR_register_on_exit(LPM3_bits);
+        __no_operation();
+    }
+}