iBoot/drivers/samsung/dwi/dwi.c

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2023-07-08 13:03:17 -07:00
/*
* Copyright (C) 2011 Apple Inc. All rights reserved.
*
* This document is the property of Apple Inc.
* It is considered confidential and proprietary.
*
* This document may not be reproduced or transmitted in any form,
* in whole or in part, without the express written permission of
* Apple Inc.
*/
#include <debug.h>
#include <platform.h>
#include <platform/clocks.h>
#include <platform/soc/hwclocks.h>
#include "dwi.h"
#ifndef TARGET_DWI_FREQUENCY
#error TARGET_DWI_FREQUENCY not defined by the target
#endif
#ifndef TARGET_DWI_TRANSFER_GAP_US
#error TARGET_DWI_TRANSFER_GAP_US not defined by the target
#endif
int dwi_init(void)
{
u_int32_t dwi_divider, dwi_transfer_gap;
clock_gate(CLK_DWI, true);
dwi_divider = (clock_get_frequency(CLK_NCLK) + TARGET_DWI_FREQUENCY - 1) / TARGET_DWI_FREQUENCY;
dwi_transfer_gap = (clock_get_frequency(CLK_NCLK) * TARGET_DWI_TRANSFER_GAP_US) / 1000000;
rDWI_CLOCK_CONFIG = DWI_CLOCK_CONFIG_CLOCK_SCALER(dwi_divider) | DWI_CLOCK_CONFIG_TX_CPHA_1;
rDWI_TRANSFER_GAP = dwi_transfer_gap;
return 0;
}
int dwi_send_backlight_command(uint32_t backlight_command, uint32_t backlight_level)
{
rDWI_ITR0_TX_DATA = (backlight_command << 28) | (backlight_level & 0x7FF);
rDWI_ITR0_CONTROL = DWI_TR_CTRL_BYTE_SWAP | DWI_TR_CTRL_BYTE_CNT(4) | DWI_TR_CTRL_TRAN_EN;
return 0;
}