u-boot-brain/drivers/adc/meson-saradc.c
Marek Szyprowski 81b1c47596 adc: meson-saradc: skip hardware init only if ADC is enabled
The driver skips hardware initialization if it is already configured by
the earlier bootloader stage (BL30). Skip the initialization only if the
hardware is really initialized and enabled.

Signed-off-by: Marek Szyprowski <m.szyprowski@samsung.com>
Reviewed-by: Neil Armstrong <narmstrong@baylibre.com>
Tested-by: Jaehoon Chung <jh80.chung@samsung.com>
Reviewed-by: Jaehoon Chung <jh80.chung@samsung.com>
Signed-off-by: Neil Armstrong <narmstrong@baylibre.com>
2021-01-11 14:59:54 +01:00

731 lines
22 KiB
C

// SPDX-License-Identifier: GPL-2.0+
/*
* Copyright (C) 2017 Martin Blumenstingl <martin.blumenstingl@googlemail.com>
* Copyright (C) 2018 BayLibre, SAS
* Author: Neil Armstrong <narmstrong@baylibre.com>
*
* Amlogic Meson Successive Approximation Register (SAR) A/D Converter
*/
#include <common.h>
#include <adc.h>
#include <clk.h>
#include <dm.h>
#include <regmap.h>
#include <errno.h>
#include <asm/io.h>
#include <linux/bitops.h>
#include <linux/delay.h>
#include <linux/math64.h>
#include <linux/bitfield.h>
#define MESON_SAR_ADC_REG0 0x00
#define MESON_SAR_ADC_REG0_PANEL_DETECT BIT(31)
#define MESON_SAR_ADC_REG0_BUSY_MASK GENMASK(30, 28)
#define MESON_SAR_ADC_REG0_DELTA_BUSY BIT(30)
#define MESON_SAR_ADC_REG0_AVG_BUSY BIT(29)
#define MESON_SAR_ADC_REG0_SAMPLE_BUSY BIT(28)
#define MESON_SAR_ADC_REG0_FIFO_FULL BIT(27)
#define MESON_SAR_ADC_REG0_FIFO_EMPTY BIT(26)
#define MESON_SAR_ADC_REG0_FIFO_COUNT_MASK GENMASK(25, 21)
#define MESON_SAR_ADC_REG0_ADC_BIAS_CTRL_MASK GENMASK(20, 19)
#define MESON_SAR_ADC_REG0_CURR_CHAN_ID_MASK GENMASK(18, 16)
#define MESON_SAR_ADC_REG0_ADC_TEMP_SEN_SEL BIT(15)
#define MESON_SAR_ADC_REG0_SAMPLING_STOP BIT(14)
#define MESON_SAR_ADC_REG0_CHAN_DELTA_EN_MASK GENMASK(13, 12)
#define MESON_SAR_ADC_REG0_DETECT_IRQ_POL BIT(10)
#define MESON_SAR_ADC_REG0_DETECT_IRQ_EN BIT(9)
#define MESON_SAR_ADC_REG0_FIFO_CNT_IRQ_MASK GENMASK(8, 4)
#define MESON_SAR_ADC_REG0_FIFO_IRQ_EN BIT(3)
#define MESON_SAR_ADC_REG0_SAMPLING_START BIT(2)
#define MESON_SAR_ADC_REG0_CONTINUOUS_EN BIT(1)
#define MESON_SAR_ADC_REG0_SAMPLE_ENGINE_ENABLE BIT(0)
#define MESON_SAR_ADC_CHAN_LIST 0x04
#define MESON_SAR_ADC_CHAN_LIST_MAX_INDEX_MASK GENMASK(26, 24)
#define MESON_SAR_ADC_CHAN_LIST_ENTRY_MASK(_chan) \
(GENMASK(2, 0) << ((_chan) * 3))
#define MESON_SAR_ADC_AVG_CNTL 0x08
#define MESON_SAR_ADC_AVG_CNTL_AVG_MODE_SHIFT(_chan) \
(16 + ((_chan) * 2))
#define MESON_SAR_ADC_AVG_CNTL_AVG_MODE_MASK(_chan) \
(GENMASK(17, 16) << ((_chan) * 2))
#define MESON_SAR_ADC_AVG_CNTL_NUM_SAMPLES_SHIFT(_chan) \
(0 + ((_chan) * 2))
#define MESON_SAR_ADC_AVG_CNTL_NUM_SAMPLES_MASK(_chan) \
(GENMASK(1, 0) << ((_chan) * 2))
#define MESON_SAR_ADC_REG3 0x0c
#define MESON_SAR_ADC_REG3_CNTL_USE_SC_DLY BIT(31)
#define MESON_SAR_ADC_REG3_CLK_EN BIT(30)
#define MESON_SAR_ADC_REG3_BL30_INITIALIZED BIT(28)
#define MESON_SAR_ADC_REG3_CTRL_CONT_RING_COUNTER_EN BIT(27)
#define MESON_SAR_ADC_REG3_CTRL_SAMPLING_CLOCK_PHASE BIT(26)
#define MESON_SAR_ADC_REG3_CTRL_CHAN7_MUX_SEL_MASK GENMASK(25, 23)
#define MESON_SAR_ADC_REG3_DETECT_EN BIT(22)
#define MESON_SAR_ADC_REG3_ADC_EN BIT(21)
#define MESON_SAR_ADC_REG3_PANEL_DETECT_COUNT_MASK GENMASK(20, 18)
#define MESON_SAR_ADC_REG3_PANEL_DETECT_FILTER_TB_MASK GENMASK(17, 16)
#define MESON_SAR_ADC_REG3_ADC_CLK_DIV_SHIFT 10
#define MESON_SAR_ADC_REG3_ADC_CLK_DIV_WIDTH 5
#define MESON_SAR_ADC_REG3_BLOCK_DLY_SEL_MASK GENMASK(9, 8)
#define MESON_SAR_ADC_REG3_BLOCK_DLY_MASK GENMASK(7, 0)
#define MESON_SAR_ADC_DELAY 0x10
#define MESON_SAR_ADC_DELAY_INPUT_DLY_SEL_MASK GENMASK(25, 24)
#define MESON_SAR_ADC_DELAY_BL30_BUSY BIT(15)
#define MESON_SAR_ADC_DELAY_KERNEL_BUSY BIT(14)
#define MESON_SAR_ADC_DELAY_INPUT_DLY_CNT_MASK GENMASK(23, 16)
#define MESON_SAR_ADC_DELAY_SAMPLE_DLY_SEL_MASK GENMASK(9, 8)
#define MESON_SAR_ADC_DELAY_SAMPLE_DLY_CNT_MASK GENMASK(7, 0)
#define MESON_SAR_ADC_LAST_RD 0x14
#define MESON_SAR_ADC_LAST_RD_LAST_CHANNEL1_MASK GENMASK(23, 16)
#define MESON_SAR_ADC_LAST_RD_LAST_CHANNEL0_MASK GENMASK(9, 0)
#define MESON_SAR_ADC_FIFO_RD 0x18
#define MESON_SAR_ADC_FIFO_RD_CHAN_ID_MASK GENMASK(14, 12)
#define MESON_SAR_ADC_FIFO_RD_SAMPLE_VALUE_MASK GENMASK(11, 0)
#define MESON_SAR_ADC_AUX_SW 0x1c
#define MESON_SAR_ADC_AUX_SW_MUX_SEL_CHAN_SHIFT(_chan) \
(8 + (((_chan) - 2) * 3))
#define MESON_SAR_ADC_AUX_SW_VREF_P_MUX BIT(6)
#define MESON_SAR_ADC_AUX_SW_VREF_N_MUX BIT(5)
#define MESON_SAR_ADC_AUX_SW_MODE_SEL BIT(4)
#define MESON_SAR_ADC_AUX_SW_YP_DRIVE_SW BIT(3)
#define MESON_SAR_ADC_AUX_SW_XP_DRIVE_SW BIT(2)
#define MESON_SAR_ADC_AUX_SW_YM_DRIVE_SW BIT(1)
#define MESON_SAR_ADC_AUX_SW_XM_DRIVE_SW BIT(0)
#define MESON_SAR_ADC_CHAN_10_SW 0x20
#define MESON_SAR_ADC_CHAN_10_SW_CHAN1_MUX_SEL_MASK GENMASK(25, 23)
#define MESON_SAR_ADC_CHAN_10_SW_CHAN1_VREF_P_MUX BIT(22)
#define MESON_SAR_ADC_CHAN_10_SW_CHAN1_VREF_N_MUX BIT(21)
#define MESON_SAR_ADC_CHAN_10_SW_CHAN1_MODE_SEL BIT(20)
#define MESON_SAR_ADC_CHAN_10_SW_CHAN1_YP_DRIVE_SW BIT(19)
#define MESON_SAR_ADC_CHAN_10_SW_CHAN1_XP_DRIVE_SW BIT(18)
#define MESON_SAR_ADC_CHAN_10_SW_CHAN1_YM_DRIVE_SW BIT(17)
#define MESON_SAR_ADC_CHAN_10_SW_CHAN1_XM_DRIVE_SW BIT(16)
#define MESON_SAR_ADC_CHAN_10_SW_CHAN0_MUX_SEL_MASK GENMASK(9, 7)
#define MESON_SAR_ADC_CHAN_10_SW_CHAN0_VREF_P_MUX BIT(6)
#define MESON_SAR_ADC_CHAN_10_SW_CHAN0_VREF_N_MUX BIT(5)
#define MESON_SAR_ADC_CHAN_10_SW_CHAN0_MODE_SEL BIT(4)
#define MESON_SAR_ADC_CHAN_10_SW_CHAN0_YP_DRIVE_SW BIT(3)
#define MESON_SAR_ADC_CHAN_10_SW_CHAN0_XP_DRIVE_SW BIT(2)
#define MESON_SAR_ADC_CHAN_10_SW_CHAN0_YM_DRIVE_SW BIT(1)
#define MESON_SAR_ADC_CHAN_10_SW_CHAN0_XM_DRIVE_SW BIT(0)
#define MESON_SAR_ADC_DETECT_IDLE_SW 0x24
#define MESON_SAR_ADC_DETECT_IDLE_SW_DETECT_SW_EN BIT(26)
#define MESON_SAR_ADC_DETECT_IDLE_SW_DETECT_MUX_MASK GENMASK(25, 23)
#define MESON_SAR_ADC_DETECT_IDLE_SW_DETECT_VREF_P_MUX BIT(22)
#define MESON_SAR_ADC_DETECT_IDLE_SW_DETECT_VREF_N_MUX BIT(21)
#define MESON_SAR_ADC_DETECT_IDLE_SW_DETECT_MODE_SEL BIT(20)
#define MESON_SAR_ADC_DETECT_IDLE_SW_DETECT_YP_DRIVE_SW BIT(19)
#define MESON_SAR_ADC_DETECT_IDLE_SW_DETECT_XP_DRIVE_SW BIT(18)
#define MESON_SAR_ADC_DETECT_IDLE_SW_DETECT_YM_DRIVE_SW BIT(17)
#define MESON_SAR_ADC_DETECT_IDLE_SW_DETECT_XM_DRIVE_SW BIT(16)
#define MESON_SAR_ADC_DETECT_IDLE_SW_IDLE_MUX_SEL_MASK GENMASK(9, 7)
#define MESON_SAR_ADC_DETECT_IDLE_SW_IDLE_VREF_P_MUX BIT(6)
#define MESON_SAR_ADC_DETECT_IDLE_SW_IDLE_VREF_N_MUX BIT(5)
#define MESON_SAR_ADC_DETECT_IDLE_SW_IDLE_MODE_SEL BIT(4)
#define MESON_SAR_ADC_DETECT_IDLE_SW_IDLE_YP_DRIVE_SW BIT(3)
#define MESON_SAR_ADC_DETECT_IDLE_SW_IDLE_XP_DRIVE_SW BIT(2)
#define MESON_SAR_ADC_DETECT_IDLE_SW_IDLE_YM_DRIVE_SW BIT(1)
#define MESON_SAR_ADC_DETECT_IDLE_SW_IDLE_XM_DRIVE_SW BIT(0)
#define MESON_SAR_ADC_DELTA_10 0x28
#define MESON_SAR_ADC_DELTA_10_TEMP_SEL BIT(27)
#define MESON_SAR_ADC_DELTA_10_TS_REVE1 BIT(26)
#define MESON_SAR_ADC_DELTA_10_CHAN1_DELTA_VALUE_MASK GENMASK(25, 16)
#define MESON_SAR_ADC_DELTA_10_TS_REVE0 BIT(15)
#define MESON_SAR_ADC_DELTA_10_TS_C_SHIFT 11
#define MESON_SAR_ADC_DELTA_10_TS_C_MASK GENMASK(14, 11)
#define MESON_SAR_ADC_DELTA_10_TS_VBG_EN BIT(10)
#define MESON_SAR_ADC_DELTA_10_CHAN0_DELTA_VALUE_MASK GENMASK(9, 0)
/*
* NOTE: registers from here are undocumented (the vendor Linux kernel driver
* and u-boot source served as reference). These only seem to be relevant on
* GXBB and newer.
*/
#define MESON_SAR_ADC_REG11 0x2c
#define MESON_SAR_ADC_REG11_BANDGAP_EN BIT(13)
#define MESON_SAR_ADC_REG13 0x34
#define MESON_SAR_ADC_REG13_12BIT_CALIBRATION_MASK GENMASK(13, 8)
#define MESON_SAR_ADC_MAX_FIFO_SIZE 32
#define MESON_SAR_ADC_TIMEOUT 100 /* ms */
#define NUM_CHANNELS 8
#define MILLION 1000000
struct meson_saradc_data {
int num_bits;
};
struct meson_saradc_priv {
const struct meson_saradc_data *data;
struct regmap *regmap;
struct clk core_clk;
struct clk adc_clk;
bool initialized;
int active_channel;
int calibbias;
int calibscale;
};
static unsigned int
meson_saradc_get_fifo_count(struct meson_saradc_priv *priv)
{
u32 regval;
regmap_read(priv->regmap, MESON_SAR_ADC_REG0, &regval);
return FIELD_GET(MESON_SAR_ADC_REG0_FIFO_COUNT_MASK, regval);
}
static int meson_saradc_lock(struct meson_saradc_priv *priv)
{
uint val, timeout = 10000;
/* prevent BL30 from using the SAR ADC while we are using it */
regmap_update_bits(priv->regmap, MESON_SAR_ADC_DELAY,
MESON_SAR_ADC_DELAY_KERNEL_BUSY,
MESON_SAR_ADC_DELAY_KERNEL_BUSY);
/*
* wait until BL30 releases it's lock (so we can use the SAR ADC)
*/
do {
udelay(1);
regmap_read(priv->regmap, MESON_SAR_ADC_DELAY, &val);
} while (val & MESON_SAR_ADC_DELAY_BL30_BUSY && timeout--);
if (timeout < 0) {
printf("Timeout while waiting for BL30 unlock\n");
return -ETIMEDOUT;
}
return 0;
}
static void meson_saradc_unlock(struct meson_saradc_priv *priv)
{
/* allow BL30 to use the SAR ADC again */
regmap_update_bits(priv->regmap, MESON_SAR_ADC_DELAY,
MESON_SAR_ADC_DELAY_KERNEL_BUSY, 0);
}
static void meson_saradc_clear_fifo(struct meson_saradc_priv *priv)
{
unsigned int count, tmp;
for (count = 0; count < MESON_SAR_ADC_MAX_FIFO_SIZE; count++) {
if (!meson_saradc_get_fifo_count(priv))
break;
regmap_read(priv->regmap, MESON_SAR_ADC_FIFO_RD, &tmp);
}
}
static int meson_saradc_calib_val(struct meson_saradc_priv *priv, int val)
{
int tmp;
/* use val_calib = scale * val_raw + offset calibration function */
tmp = div_s64((s64)val * priv->calibscale, MILLION) + priv->calibbias;
return clamp(tmp, 0, (1 << priv->data->num_bits) - 1);
}
static int meson_saradc_wait_busy_clear(struct meson_saradc_priv *priv)
{
uint regval, timeout = 10000;
/*
* NOTE: we need a small delay before reading the status, otherwise
* the sample engine may not have started internally (which would
* seem to us that sampling is already finished).
*/
do {
udelay(1);
regmap_read(priv->regmap, MESON_SAR_ADC_REG0, &regval);
} while (FIELD_GET(MESON_SAR_ADC_REG0_BUSY_MASK, regval) && timeout--);
if (timeout < 0)
return -ETIMEDOUT;
return 0;
}
static int meson_saradc_read_raw_sample(struct meson_saradc_priv *priv,
unsigned int channel, uint *val)
{
uint regval, fifo_chan, fifo_val, count;
int ret;
ret = meson_saradc_wait_busy_clear(priv);
if (ret)
return ret;
count = meson_saradc_get_fifo_count(priv);
if (count != 1) {
printf("ADC FIFO has %d element(s) instead of one\n", count);
return -EINVAL;
}
regmap_read(priv->regmap, MESON_SAR_ADC_FIFO_RD, &regval);
fifo_chan = FIELD_GET(MESON_SAR_ADC_FIFO_RD_CHAN_ID_MASK, regval);
if (fifo_chan != channel) {
printf("ADC FIFO entry belongs to channel %d instead of %d\n",
fifo_chan, channel);
return -EINVAL;
}
fifo_val = FIELD_GET(MESON_SAR_ADC_FIFO_RD_SAMPLE_VALUE_MASK, regval);
fifo_val &= GENMASK(priv->data->num_bits - 1, 0);
*val = meson_saradc_calib_val(priv, fifo_val);
return 0;
}
static void meson_saradc_start_sample_engine(struct meson_saradc_priv *priv)
{
regmap_update_bits(priv->regmap, MESON_SAR_ADC_REG0,
MESON_SAR_ADC_REG0_FIFO_IRQ_EN,
MESON_SAR_ADC_REG0_FIFO_IRQ_EN);
regmap_update_bits(priv->regmap, MESON_SAR_ADC_REG0,
MESON_SAR_ADC_REG0_SAMPLE_ENGINE_ENABLE,
MESON_SAR_ADC_REG0_SAMPLE_ENGINE_ENABLE);
regmap_update_bits(priv->regmap, MESON_SAR_ADC_REG0,
MESON_SAR_ADC_REG0_SAMPLING_START,
MESON_SAR_ADC_REG0_SAMPLING_START);
}
static void meson_saradc_stop_sample_engine(struct meson_saradc_priv *priv)
{
regmap_update_bits(priv->regmap, MESON_SAR_ADC_REG0,
MESON_SAR_ADC_REG0_FIFO_IRQ_EN, 0);
regmap_update_bits(priv->regmap, MESON_SAR_ADC_REG0,
MESON_SAR_ADC_REG0_SAMPLING_STOP,
MESON_SAR_ADC_REG0_SAMPLING_STOP);
/* wait until all modules are stopped */
meson_saradc_wait_busy_clear(priv);
regmap_update_bits(priv->regmap, MESON_SAR_ADC_REG0,
MESON_SAR_ADC_REG0_SAMPLE_ENGINE_ENABLE, 0);
}
enum meson_saradc_avg_mode {
NO_AVERAGING = 0x0,
MEAN_AVERAGING = 0x1,
MEDIAN_AVERAGING = 0x2,
};
enum meson_saradc_num_samples {
ONE_SAMPLE = 0x0,
TWO_SAMPLES = 0x1,
FOUR_SAMPLES = 0x2,
EIGHT_SAMPLES = 0x3,
};
static void meson_saradc_set_averaging(struct meson_saradc_priv *priv,
unsigned int channel,
enum meson_saradc_avg_mode mode,
enum meson_saradc_num_samples samples)
{
int val;
val = samples << MESON_SAR_ADC_AVG_CNTL_NUM_SAMPLES_SHIFT(channel);
regmap_update_bits(priv->regmap, MESON_SAR_ADC_AVG_CNTL,
MESON_SAR_ADC_AVG_CNTL_NUM_SAMPLES_MASK(channel),
val);
val = mode << MESON_SAR_ADC_AVG_CNTL_AVG_MODE_SHIFT(channel);
regmap_update_bits(priv->regmap, MESON_SAR_ADC_AVG_CNTL,
MESON_SAR_ADC_AVG_CNTL_AVG_MODE_MASK(channel), val);
}
static void meson_saradc_enable_channel(struct meson_saradc_priv *priv,
unsigned int channel)
{
uint regval;
/*
* the SAR ADC engine allows sampling multiple channels at the same
* time. to keep it simple we're only working with one *internal*
* channel, which starts counting at index 0 (which means: count = 1).
*/
regval = FIELD_PREP(MESON_SAR_ADC_CHAN_LIST_MAX_INDEX_MASK, 0);
regmap_update_bits(priv->regmap, MESON_SAR_ADC_CHAN_LIST,
MESON_SAR_ADC_CHAN_LIST_MAX_INDEX_MASK, regval);
/* map channel index 0 to the channel which we want to read */
regval = FIELD_PREP(MESON_SAR_ADC_CHAN_LIST_ENTRY_MASK(0), channel);
regmap_update_bits(priv->regmap, MESON_SAR_ADC_CHAN_LIST,
MESON_SAR_ADC_CHAN_LIST_ENTRY_MASK(0), regval);
regval = FIELD_PREP(MESON_SAR_ADC_DETECT_IDLE_SW_DETECT_MUX_MASK,
channel);
regmap_update_bits(priv->regmap, MESON_SAR_ADC_DETECT_IDLE_SW,
MESON_SAR_ADC_DETECT_IDLE_SW_DETECT_MUX_MASK,
regval);
regval = FIELD_PREP(MESON_SAR_ADC_DETECT_IDLE_SW_IDLE_MUX_SEL_MASK,
channel);
regmap_update_bits(priv->regmap, MESON_SAR_ADC_DETECT_IDLE_SW,
MESON_SAR_ADC_DETECT_IDLE_SW_IDLE_MUX_SEL_MASK,
regval);
if (channel == 6)
regmap_update_bits(priv->regmap, MESON_SAR_ADC_DELTA_10,
MESON_SAR_ADC_DELTA_10_TEMP_SEL, 0);
}
static int meson_saradc_get_sample(struct meson_saradc_priv *priv,
int chan, uint *val)
{
int ret;
ret = meson_saradc_lock(priv);
if (ret)
return ret;
/* clear the FIFO to make sure we're not reading old values */
meson_saradc_clear_fifo(priv);
meson_saradc_set_averaging(priv, chan, MEAN_AVERAGING, EIGHT_SAMPLES);
meson_saradc_enable_channel(priv, chan);
meson_saradc_start_sample_engine(priv);
ret = meson_saradc_read_raw_sample(priv, chan, val);
meson_saradc_stop_sample_engine(priv);
meson_saradc_unlock(priv);
if (ret) {
printf("failed to read sample for channel %d: %d\n",
chan, ret);
return ret;
}
return 0;
}
static int meson_saradc_channel_data(struct udevice *dev, int channel,
unsigned int *data)
{
struct meson_saradc_priv *priv = dev_get_priv(dev);
if (channel != priv->active_channel) {
pr_err("Requested channel is not active!");
return -EINVAL;
}
return meson_saradc_get_sample(priv, channel, data);
}
enum meson_saradc_chan7_mux_sel {
CHAN7_MUX_VSS = 0x0,
CHAN7_MUX_VDD_DIV4 = 0x1,
CHAN7_MUX_VDD_DIV2 = 0x2,
CHAN7_MUX_VDD_MUL3_DIV4 = 0x3,
CHAN7_MUX_VDD = 0x4,
CHAN7_MUX_CH7_INPUT = 0x7,
};
static void meson_saradc_set_chan7_mux(struct meson_saradc_priv *priv,
enum meson_saradc_chan7_mux_sel sel)
{
u32 regval;
regval = FIELD_PREP(MESON_SAR_ADC_REG3_CTRL_CHAN7_MUX_SEL_MASK, sel);
regmap_update_bits(priv->regmap, MESON_SAR_ADC_REG3,
MESON_SAR_ADC_REG3_CTRL_CHAN7_MUX_SEL_MASK, regval);
udelay(20);
}
static int meson_saradc_calib(struct meson_saradc_priv *priv)
{
uint nominal0, nominal1, value0, value1;
int ret;
/* use points 25% and 75% for calibration */
nominal0 = (1 << priv->data->num_bits) / 4;
nominal1 = (1 << priv->data->num_bits) * 3 / 4;
meson_saradc_set_chan7_mux(priv, CHAN7_MUX_VDD_DIV4);
udelay(20);
ret = meson_saradc_get_sample(priv, 7, &value0);
if (ret < 0)
goto out;
meson_saradc_set_chan7_mux(priv, CHAN7_MUX_VDD_MUL3_DIV4);
udelay(20);
ret = meson_saradc_get_sample(priv, 7, &value1);
if (ret < 0)
goto out;
if (value1 <= value0) {
ret = -EINVAL;
goto out;
}
priv->calibscale = div_s64((nominal1 - nominal0) * (s64)MILLION,
value1 - value0);
priv->calibbias = nominal0 - div_s64((s64)value0 * priv->calibscale,
MILLION);
ret = 0;
out:
meson_saradc_set_chan7_mux(priv, CHAN7_MUX_CH7_INPUT);
return ret;
}
static int meson_saradc_init(struct meson_saradc_priv *priv)
{
uint regval;
int ret, i;
priv->calibscale = MILLION;
/*
* make sure we start at CH7 input since the other muxes are only used
* for internal calibration.
*/
meson_saradc_set_chan7_mux(priv, CHAN7_MUX_CH7_INPUT);
/*
* leave sampling delay and the input clocks as configured by
* BL30 to make sure BL30 gets the values it expects when
* reading the temperature sensor.
*/
regmap_read(priv->regmap, MESON_SAR_ADC_REG3, &regval);
if (regval & MESON_SAR_ADC_REG3_BL30_INITIALIZED) {
regmap_read(priv->regmap, MESON_SAR_ADC_REG3, &regval);
if (regval & MESON_SAR_ADC_REG3_ADC_EN)
return 0;
}
meson_saradc_stop_sample_engine(priv);
/* update the channel 6 MUX to select the temperature sensor */
regmap_update_bits(priv->regmap, MESON_SAR_ADC_REG0,
MESON_SAR_ADC_REG0_ADC_TEMP_SEN_SEL,
MESON_SAR_ADC_REG0_ADC_TEMP_SEN_SEL);
/* disable all channels by default */
regmap_write(priv->regmap, MESON_SAR_ADC_CHAN_LIST, 0x0);
regmap_update_bits(priv->regmap, MESON_SAR_ADC_REG3,
MESON_SAR_ADC_REG3_CTRL_SAMPLING_CLOCK_PHASE, 0);
regmap_update_bits(priv->regmap, MESON_SAR_ADC_REG3,
MESON_SAR_ADC_REG3_CNTL_USE_SC_DLY,
MESON_SAR_ADC_REG3_CNTL_USE_SC_DLY);
/* delay between two samples = (10+1) * 1uS */
regmap_update_bits(priv->regmap, MESON_SAR_ADC_DELAY,
MESON_SAR_ADC_DELAY_INPUT_DLY_CNT_MASK,
FIELD_PREP(MESON_SAR_ADC_DELAY_SAMPLE_DLY_CNT_MASK,
10));
regmap_update_bits(priv->regmap, MESON_SAR_ADC_DELAY,
MESON_SAR_ADC_DELAY_SAMPLE_DLY_SEL_MASK,
FIELD_PREP(MESON_SAR_ADC_DELAY_SAMPLE_DLY_SEL_MASK,
0));
/* delay between two samples = (10+1) * 1uS */
regmap_update_bits(priv->regmap, MESON_SAR_ADC_DELAY,
MESON_SAR_ADC_DELAY_INPUT_DLY_CNT_MASK,
FIELD_PREP(MESON_SAR_ADC_DELAY_INPUT_DLY_CNT_MASK,
10));
regmap_update_bits(priv->regmap, MESON_SAR_ADC_DELAY,
MESON_SAR_ADC_DELAY_INPUT_DLY_SEL_MASK,
FIELD_PREP(MESON_SAR_ADC_DELAY_INPUT_DLY_SEL_MASK,
1));
/*
* set up the input channel muxes in MESON_SAR_ADC_CHAN_10_SW
* (0 = SAR_ADC_CH0, 1 = SAR_ADC_CH1)
*/
regval = FIELD_PREP(MESON_SAR_ADC_CHAN_10_SW_CHAN0_MUX_SEL_MASK, 0);
regmap_update_bits(priv->regmap, MESON_SAR_ADC_CHAN_10_SW,
MESON_SAR_ADC_CHAN_10_SW_CHAN0_MUX_SEL_MASK,
regval);
regval = FIELD_PREP(MESON_SAR_ADC_CHAN_10_SW_CHAN1_MUX_SEL_MASK, 1);
regmap_update_bits(priv->regmap, MESON_SAR_ADC_CHAN_10_SW,
MESON_SAR_ADC_CHAN_10_SW_CHAN1_MUX_SEL_MASK,
regval);
/*
* set up the input channel muxes in MESON_SAR_ADC_AUX_SW
* (2 = SAR_ADC_CH2, 3 = SAR_ADC_CH3, ...) and enable
* MESON_SAR_ADC_AUX_SW_YP_DRIVE_SW and
* MESON_SAR_ADC_AUX_SW_XP_DRIVE_SW like the vendor driver.
*/
regval = 0;
for (i = 2; i <= 7; i++)
regval |= i << MESON_SAR_ADC_AUX_SW_MUX_SEL_CHAN_SHIFT(i);
regval |= MESON_SAR_ADC_AUX_SW_YP_DRIVE_SW;
regval |= MESON_SAR_ADC_AUX_SW_XP_DRIVE_SW;
regmap_write(priv->regmap, MESON_SAR_ADC_AUX_SW, regval);
ret = meson_saradc_lock(priv);
if (ret)
return ret;
#if CONFIG_IS_ENABLED(CLK)
ret = clk_enable(&priv->core_clk);
if (ret)
return ret;
#endif
regval = FIELD_PREP(MESON_SAR_ADC_REG0_FIFO_CNT_IRQ_MASK, 1);
regmap_update_bits(priv->regmap, MESON_SAR_ADC_REG0,
MESON_SAR_ADC_REG0_FIFO_CNT_IRQ_MASK, regval);
regmap_update_bits(priv->regmap, MESON_SAR_ADC_REG11,
MESON_SAR_ADC_REG11_BANDGAP_EN,
MESON_SAR_ADC_REG11_BANDGAP_EN);
regmap_update_bits(priv->regmap, MESON_SAR_ADC_REG3,
MESON_SAR_ADC_REG3_ADC_EN,
MESON_SAR_ADC_REG3_ADC_EN);
udelay(5);
#if CONFIG_IS_ENABLED(CLK)
ret = clk_enable(&priv->adc_clk);
if (ret)
return ret;
#endif
meson_saradc_unlock(priv);
ret = meson_saradc_calib(priv);
if (ret) {
printf("calibration failed\n");
return -EIO;
}
return 0;
}
static int meson_saradc_start_channel(struct udevice *dev, int channel)
{
struct meson_saradc_priv *priv = dev_get_priv(dev);
if (channel < 0 || channel >= NUM_CHANNELS) {
printf("Requested channel is invalid!");
return -EINVAL;
}
if (!priv->initialized) {
int ret;
ret = meson_saradc_init(priv);
if (ret)
return ret;
priv->initialized = true;
}
priv->active_channel = channel;
return 0;
}
static int meson_saradc_stop(struct udevice *dev)
{
struct meson_saradc_priv *priv = dev_get_priv(dev);
priv->active_channel = -1;
return 0;
}
static int meson_saradc_probe(struct udevice *dev)
{
struct meson_saradc_priv *priv = dev_get_priv(dev);
int ret;
ret = regmap_init_mem(dev_ofnode(dev), &priv->regmap);
if (ret)
return ret;
#if CONFIG_IS_ENABLED(CLK)
ret = clk_get_by_name(dev, "core", &priv->core_clk);
if (ret)
return ret;
ret = clk_get_by_name(dev, "adc_clk", &priv->adc_clk);
if (ret)
return ret;
#endif
priv->active_channel = -1;
return 0;
}
int meson_saradc_ofdata_to_platdata(struct udevice *dev)
{
struct adc_uclass_platdata *uc_pdata = dev_get_uclass_platdata(dev);
struct meson_saradc_priv *priv = dev_get_priv(dev);
priv->data = (struct meson_saradc_data *)dev_get_driver_data(dev);
uc_pdata->data_mask = GENMASK(priv->data->num_bits - 1, 0);
uc_pdata->data_format = ADC_DATA_FORMAT_BIN;
uc_pdata->data_timeout_us = MESON_SAR_ADC_TIMEOUT * 1000;
uc_pdata->channel_mask = GENMASK(NUM_CHANNELS - 1, 0);
return 0;
}
static const struct adc_ops meson_saradc_ops = {
.start_channel = meson_saradc_start_channel,
.channel_data = meson_saradc_channel_data,
.stop = meson_saradc_stop,
};
static const struct meson_saradc_data gxbb_saradc_data = {
.num_bits = 10,
};
static const struct meson_saradc_data gxl_saradc_data = {
.num_bits = 12,
};
static const struct udevice_id meson_saradc_ids[] = {
{ .compatible = "amlogic,meson-gxbb-saradc",
.data = (ulong)&gxbb_saradc_data },
{ .compatible = "amlogic,meson-gxl-saradc",
.data = (ulong)&gxl_saradc_data },
{ .compatible = "amlogic,meson-gxm-saradc",
.data = (ulong)&gxl_saradc_data },
{ .compatible = "amlogic,meson-g12a-saradc",
.data = (ulong)&gxl_saradc_data },
{ }
};
U_BOOT_DRIVER(meson_saradc) = {
.name = "meson_saradc",
.id = UCLASS_ADC,
.of_match = meson_saradc_ids,
.ops = &meson_saradc_ops,
.probe = meson_saradc_probe,
.ofdata_to_platdata = meson_saradc_ofdata_to_platdata,
.priv_auto_alloc_size = sizeof(struct meson_saradc_priv),
};