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      1 // SPDX-License-Identifier: GPL-2.0+
      2 /*
      3  * Freescale i.MX28 Battery measurement init
      4  *
      5  * Copyright (C) 2011 Marek Vasut <marek.vasut (at) gmail.com>
      6  * on behalf of DENX Software Engineering GmbH
      7  */
      8 
      9 #include <common.h>
     10 #include <config.h>
     11 #include <asm/io.h>
     12 #include <asm/arch/imx-regs.h>
     13 
     14 #include "mxs_init.h"
     15 
     16 void mxs_lradc_init(void)
     17 {
     18 	struct mxs_lradc_regs *regs = (struct mxs_lradc_regs *)MXS_LRADC_BASE;
     19 
     20 	debug("SPL: Initialisating LRADC\n");
     21 
     22 	writel(LRADC_CTRL0_SFTRST, &regs->hw_lradc_ctrl0_clr);
     23 	writel(LRADC_CTRL0_CLKGATE, &regs->hw_lradc_ctrl0_clr);
     24 	writel(LRADC_CTRL0_ONCHIP_GROUNDREF, &regs->hw_lradc_ctrl0_clr);
     25 
     26 	clrsetbits_le32(&regs->hw_lradc_ctrl3,
     27 			LRADC_CTRL3_CYCLE_TIME_MASK,
     28 			LRADC_CTRL3_CYCLE_TIME_6MHZ);
     29 
     30 	clrsetbits_le32(&regs->hw_lradc_ctrl4,
     31 			LRADC_CTRL4_LRADC7SELECT_MASK |
     32 			LRADC_CTRL4_LRADC6SELECT_MASK,
     33 			LRADC_CTRL4_LRADC7SELECT_CHANNEL7 |
     34 			LRADC_CTRL4_LRADC6SELECT_CHANNEL10);
     35 }
     36 
     37 void mxs_lradc_enable_batt_measurement(void)
     38 {
     39 	struct mxs_lradc_regs *regs = (struct mxs_lradc_regs *)MXS_LRADC_BASE;
     40 
     41 	debug("SPL: Enabling LRADC battery measurement\n");
     42 
     43 	/* Check if the channel is present at all. */
     44 	if (!(readl(&regs->hw_lradc_status) & LRADC_STATUS_CHANNEL7_PRESENT)) {
     45 		debug("SPL: LRADC channel 7 is not present - aborting\n");
     46 		return;
     47 	}
     48 
     49 	debug("SPL: LRADC channel 7 is present - configuring\n");
     50 
     51 	writel(LRADC_CTRL1_LRADC7_IRQ_EN, &regs->hw_lradc_ctrl1_clr);
     52 	writel(LRADC_CTRL1_LRADC7_IRQ, &regs->hw_lradc_ctrl1_clr);
     53 
     54 	clrsetbits_le32(&regs->hw_lradc_conversion,
     55 			LRADC_CONVERSION_SCALE_FACTOR_MASK,
     56 			LRADC_CONVERSION_SCALE_FACTOR_LI_ION);
     57 	writel(LRADC_CONVERSION_AUTOMATIC, &regs->hw_lradc_conversion_set);
     58 
     59 	/* Configure the channel. */
     60 	writel((1 << 7) << LRADC_CTRL2_DIVIDE_BY_TWO_OFFSET,
     61 		&regs->hw_lradc_ctrl2_clr);
     62 	writel(0xffffffff, &regs->hw_lradc_ch7_clr);
     63 	clrbits_le32(&regs->hw_lradc_ch7, LRADC_CH_NUM_SAMPLES_MASK);
     64 	writel(LRADC_CH_ACCUMULATE, &regs->hw_lradc_ch7_clr);
     65 
     66 	/* Schedule the channel. */
     67 	writel(1 << 7, &regs->hw_lradc_ctrl0_set);
     68 
     69 	/* Start the channel sampling. */
     70 	writel(((1 << 7) << LRADC_DELAY_TRIGGER_LRADCS_OFFSET) |
     71 		((1 << 3) << LRADC_DELAY_TRIGGER_DELAYS_OFFSET) |
     72 		100, &regs->hw_lradc_delay3);
     73 
     74 	writel(0xffffffff, &regs->hw_lradc_ch7_clr);
     75 	writel(LRADC_DELAY_KICK, &regs->hw_lradc_delay3_set);
     76 
     77 	debug("SPL: LRADC channel 7 configuration complete\n");
     78 }
     79