u-boot/arch/arm/cpu/arm926ejs/mxs/spl_lradc_init.c

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/*
* Freescale i.MX28 Battery measurement init
*
* Copyright (C) 2011 Marek Vasut <marek.vasut@gmail.com>
* on behalf of DENX Software Engineering GmbH
*
* SPDX-License-Identifier: GPL-2.0+
*/
#include <common.h>
#include <config.h>
#include <asm/io.h>
#include <asm/arch/imx-regs.h>
#include "mxs_init.h"
void mxs_lradc_init(void)
{
struct mxs_lradc_regs *regs = (struct mxs_lradc_regs *)MXS_LRADC_BASE;
writel(LRADC_CTRL0_SFTRST, &regs->hw_lradc_ctrl0_clr);
writel(LRADC_CTRL0_CLKGATE, &regs->hw_lradc_ctrl0_clr);
writel(LRADC_CTRL0_ONCHIP_GROUNDREF, &regs->hw_lradc_ctrl0_clr);
clrsetbits_le32(&regs->hw_lradc_ctrl3,
LRADC_CTRL3_CYCLE_TIME_MASK,
LRADC_CTRL3_CYCLE_TIME_6MHZ);
clrsetbits_le32(&regs->hw_lradc_ctrl4,
LRADC_CTRL4_LRADC7SELECT_MASK |
LRADC_CTRL4_LRADC6SELECT_MASK,
LRADC_CTRL4_LRADC7SELECT_CHANNEL7 |
LRADC_CTRL4_LRADC6SELECT_CHANNEL10);
}
void mxs_lradc_enable_batt_measurement(void)
{
struct mxs_lradc_regs *regs = (struct mxs_lradc_regs *)MXS_LRADC_BASE;
/* Check if the channel is present at all. */
if (!(readl(&regs->hw_lradc_status) & LRADC_STATUS_CHANNEL7_PRESENT))
return;
writel(LRADC_CTRL1_LRADC7_IRQ_EN, &regs->hw_lradc_ctrl1_clr);
writel(LRADC_CTRL1_LRADC7_IRQ, &regs->hw_lradc_ctrl1_clr);
clrsetbits_le32(&regs->hw_lradc_conversion,
LRADC_CONVERSION_SCALE_FACTOR_MASK,
LRADC_CONVERSION_SCALE_FACTOR_LI_ION);
writel(LRADC_CONVERSION_AUTOMATIC, &regs->hw_lradc_conversion_set);
/* Configure the channel. */
writel((1 << 7) << LRADC_CTRL2_DIVIDE_BY_TWO_OFFSET,
&regs->hw_lradc_ctrl2_clr);
writel(0xffffffff, &regs->hw_lradc_ch7_clr);
clrbits_le32(&regs->hw_lradc_ch7, LRADC_CH_NUM_SAMPLES_MASK);
writel(LRADC_CH_ACCUMULATE, &regs->hw_lradc_ch7_clr);
/* Schedule the channel. */
writel(1 << 7, &regs->hw_lradc_ctrl0_set);
/* Start the channel sampling. */
writel(((1 << 7) << LRADC_DELAY_TRIGGER_LRADCS_OFFSET) |
((1 << 3) << LRADC_DELAY_TRIGGER_DELAYS_OFFSET) |
100, &regs->hw_lradc_delay3);
writel(0xffffffff, &regs->hw_lradc_ch7_clr);
writel(LRADC_DELAY_KICK, &regs->hw_lradc_delay3_set);
}