76 lines
		
	
	
		
			2.8 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
			
		
		
	
	
			76 lines
		
	
	
		
			2.8 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
| /* Copyright 2021 Nick Brassel (@tzarc)
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|  *
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|  * This program is free software: you can redistribute it and/or modify
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|  * it under the terms of the GNU General Public License as published by
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|  * the Free Software Foundation, either version 2 of the License, or
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|  * (at your option) any later version.
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|  *
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|  * This program is distributed in the hope that it will be useful,
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|  * but WITHOUT ANY WARRANTY; without even the implied warranty of
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|  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
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|  * GNU General Public License for more details.
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|  *
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|  * You should have received a copy of the GNU General Public License
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|  * along with this program.  If not, see <http://www.gnu.org/licenses/>.
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|  */
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| 
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| #include <quantum.h>
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| 
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| #ifndef USBPD_UCPD1_CFG1
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| #    define USBPD_UCPD1_CFG1 (UCPD_CFG1_PSC_UCPDCLK_0 | UCPD_CFG1_TRANSWIN_3 | UCPD_CFG1_IFRGAP_4 | UCPD_CFG1_HBITCLKDIV_4)
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| #endif  // USBPD_UCPD1_CFG1
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| 
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| // Initialises the USBPD subsystem
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| __attribute__((weak)) void usbpd_init(void) {
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|     // Disable dead-battery signals
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|     PWR->CR3 |= PWR_CR3_UCPD_DBDIS;
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|     // Enable the clock for the UCPD1 peripheral
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|     RCC->APB1ENR2 |= RCC_APB1ENR2_UCPD1EN;
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| 
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|     // Copy the existing value
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|     uint32_t CFG1 = UCPD1->CFG1;
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|     // Force-disable UCPD1 before configuring
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|     CFG1 &= ~UCPD_CFG1_UCPDEN;
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|     // Configure UCPD1
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|     CFG1 = USBPD_UCPD1_CFG1;
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|     // Apply the changes
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|     UCPD1->CFG1 = CFG1;
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|     // Enable UCPD1
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|     UCPD1->CFG1 |= UCPD_CFG1_UCPDEN;
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| 
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|     // Copy the existing value
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|     uint32_t CR = UCPD1->CR;
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|     // Clear out ANASUBMODE (irrelevant as a sink device)
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|     CR &= ~UCPD_CR_ANASUBMODE_Msk;
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|     // Advertise our capabilities as a sink, with both CC lines enabled
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|     CR |= UCPD_CR_ANAMODE | UCPD_CR_CCENABLE_Msk;
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|     // Apply the changes
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|     UCPD1->CR = CR;
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| }
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| 
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| // Gets the current state of the USBPD allowance
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| __attribute__((weak)) usbpd_allowance_t usbpd_get_allowance(void) {
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|     uint32_t CR = UCPD1->CR;
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| 
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|     int ucpd_enabled = (UCPD1->CFG1 & UCPD_CFG1_UCPDEN_Msk) >> UCPD_CFG1_UCPDEN_Pos;
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|     int anamode      = (CR & UCPD_CR_ANAMODE_Msk) >> UCPD_CR_ANAMODE_Pos;
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|     int cc_enabled   = (CR & UCPD_CR_CCENABLE_Msk) >> UCPD_CR_CCENABLE_Pos;
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| 
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|     if (ucpd_enabled && anamode && cc_enabled) {
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|         uint32_t SR         = UCPD1->SR;
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|         int      vstate_cc1 = (SR & UCPD_SR_TYPEC_VSTATE_CC1_Msk) >> UCPD_SR_TYPEC_VSTATE_CC1_Pos;
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|         int      vstate_cc2 = (SR & UCPD_SR_TYPEC_VSTATE_CC2_Msk) >> UCPD_SR_TYPEC_VSTATE_CC2_Pos;
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|         int      vstate_max = vstate_cc1 > vstate_cc2 ? vstate_cc1 : vstate_cc2;
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|         switch (vstate_max) {
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|             case 0:
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|             case 1:
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|                 return USBPD_500MA;  // Note that this is 500mA (i.e. max USB 2.0), not 900mA, as we're not using USB 3.1 as a sink device.
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|             case 2:
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|                 return USBPD_1500MA;
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|             case 3:
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|                 return USBPD_3000MA;
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|         }
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|     }
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| 
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|     return USBPD_500MA;
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| } |