rockbox/firmware/target/arm/imx233/lradc-imx233.c
Amaury Pouly f4fdf1ffe2 imx233: fix lradc/adc for stmp3600 and stmp3700
The lradc architecture of the stmp3600 is rather different:
only channels 6 and 7 have configurable source and we need to
take care when allocating channels so that we can actually
measure the right channel! Delegate die temperature sensing to
the power block on stmp3600.

Change-Id: I0860eb4ea98240facc3d4a19d61684eca5f630cc
2013-06-17 00:29:25 +02:00

365 lines
11 KiB
C

/***************************************************************************
* __________ __ ___.
* Open \______ \ ____ ____ | | _\_ |__ _______ ___
* Source | _// _ \_/ ___\| |/ /| __ \ / _ \ \/ /
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* \/ \/ \/ \/ \/
* $Id$
*
* Copyright (C) 2011 by Amaury Pouly
*
* This program is free software; you can redistribute it and/or
* modify it under the terms of the GNU General Public License
* as published by the Free Software Foundation; either version 2
* of the License, or (at your option) any later version.
*
* This software is distributed on an "AS IS" basis, WITHOUT WARRANTY OF ANY
* KIND, either express or implied.
*
****************************************************************************/
#include "system.h"
#include "system-target.h"
#include "lradc-imx233.h"
#include "kernel-imx233.h"
#include "stdlib.h"
/* channels */
#if IMX233_SUBTARGET >= 3700
static struct channel_arbiter_t channel_arbiter;
#else
static struct semaphore channel_sema[LRADC_NUM_CHANNELS];
#endif
/* delay channels */
static struct channel_arbiter_t delay_arbiter;
/* battery is very special, dedicate a channel and a delay to it */
static int battery_chan;
static int battery_delay_chan;
/* irq callbacks */
static lradc_irq_fn_t irq_cb[LRADC_NUM_CHANNELS];
#define define_cb(x) \
void INT_LRADC_CH##x(void) \
{ \
INT_LRADC_CH(x); \
}
void INT_LRADC_CH(int chan)
{
if(irq_cb[chan])
irq_cb[chan](chan);
imx233_lradc_clear_channel_irq(chan);
}
define_cb(0)
define_cb(1)
define_cb(2)
define_cb(3)
define_cb(4)
define_cb(5)
define_cb(6)
define_cb(7)
void imx233_lradc_set_channel_irq_callback(int channel, lradc_irq_fn_t cb)
{
irq_cb[channel] = cb;
imx233_icoll_enable_interrupt(INT_SRC_LRADC_CHx(channel), cb != NULL);
}
void imx233_lradc_setup_channel(int channel, bool div2, bool acc, int nr_samples, int src)
{
HW_LRADC_CHn_CLR(channel) = BM_OR2(LRADC_CHn, NUM_SAMPLES, ACCUMULATE);
HW_LRADC_CHn_SET(channel) = BF_OR2(LRADC_CHn, NUM_SAMPLES(nr_samples), ACCUMULATE(acc));
if(div2)
BF_SETV(LRADC_CTRL2, DIVIDE_BY_TWO, 1 << channel);
else
BF_CLRV(LRADC_CTRL2, DIVIDE_BY_TWO, 1 << channel);
#if IMX233_SUBTARGET >= 3700
HW_LRADC_CTRL4_CLR = BM_LRADC_CTRL4_LRADCxSELECT(channel);
HW_LRADC_CTRL4_SET = src << BP_LRADC_CTRL4_LRADCxSELECT(channel);
#else
if(channel == 6)
{
BF_CLR(LRADC_CTRL2, LRADC6SELECT);
BF_SETV(LRADC_CTRL2, LRADC6SELECT, src);
}
else if(channel == 7)
{
BF_CLR(LRADC_CTRL2, LRADC7SELECT);
BF_SETV(LRADC_CTRL2, LRADC7SELECT, src);
}
else if(channel != src)
panicf("cannot configure channel %d for source %d", channel, src);
#endif
}
void imx233_lradc_setup_delay(int dchan, int trigger_lradc, int trigger_delays,
int loop_count, int delay)
{
HW_LRADC_DELAYn(dchan) = BF_OR4(LRADC_DELAYn, TRIGGER_LRADCS(trigger_lradc),
TRIGGER_DELAYS(trigger_delays), LOOP_COUNT(loop_count), DELAY(delay));
}
void imx233_lradc_clear_channel_irq(int channel)
{
BF_CLR(LRADC_CTRL1, LRADCx_IRQ(channel));
}
bool imx233_lradc_read_channel_irq(int channel)
{
return BF_RD(LRADC_CTRL1, LRADCx_IRQ(channel));
}
void imx233_lradc_enable_channel_irq(int channel, bool enable)
{
if(enable)
BF_SET(LRADC_CTRL1, LRADCx_IRQ_EN(channel));
else
BF_CLR(LRADC_CTRL1, LRADCx_IRQ_EN(channel));
imx233_lradc_clear_channel_irq(channel);
}
void imx233_lradc_kick_channel(int channel)
{
imx233_lradc_clear_channel_irq(channel);
BF_SETV(LRADC_CTRL0, SCHEDULE, 1 << channel);
}
void imx233_lradc_kick_delay(int dchan)
{
BF_SETn(LRADC_DELAYn, dchan, KICK);
}
void imx233_lradc_wait_channel(int channel)
{
/* wait for completion */
while(!imx233_lradc_read_channel_irq(channel))
yield();
}
int imx233_lradc_read_channel(int channel)
{
return BF_RDn(LRADC_CHn, channel, VALUE);
}
void imx233_lradc_clear_channel(int channel)
{
BF_CLRn(LRADC_CHn, channel, VALUE);
}
#if IMX233_SUBTARGET >= 3700
int imx233_lradc_acquire_channel(int src, int timeout)
{
(void) src;
return arbiter_acquire(&channel_arbiter, timeout);
}
void imx233_lradc_release_channel(int chan)
{
return arbiter_release(&channel_arbiter, chan);
}
void imx233_lradc_reserve_channel(int channel)
{
return arbiter_reserve(&channel_arbiter, channel);
}
#else
int imx233_lradc_acquire_channel(int src, int timeout)
{
int channel = src <= LRADC_SRC_BATTERY ? src : 6;
if(semaphore_wait(&channel_sema[channel], timeout) == OBJ_WAIT_TIMEDOUT)
return -1;
return channel;
}
void imx233_lradc_release_channel(int chan)
{
semaphore_release(&channel_sema[chan]);
}
void imx233_lradc_reserve_channel(int channel)
{
if(imx233_lradc_acquire_channel(channel, 0) == -1)
panicf("Cannot reserve a used channel");
}
#endif
int imx233_lradc_acquire_delay(int timeout)
{
return arbiter_acquire(&delay_arbiter, timeout);
}
void imx233_lradc_release_delay(int chan)
{
return arbiter_release(&delay_arbiter, chan);
}
void imx233_lradc_reserve_delay(int channel)
{
return arbiter_reserve(&delay_arbiter, channel);
}
#if IMX233_SUBTARGET >= 3700
int imx233_lradc_sense_die_temperature(int nmos_chan, int pmos_chan)
{
imx233_lradc_setup_channel(nmos_chan, false, false, 0, LRADC_SRC_NMOS_THIN);
imx233_lradc_setup_channel(pmos_chan, false, false, 0, LRADC_SRC_PMOS_THIN);
// mux sensors
BF_CLR(LRADC_CTRL2, TEMPSENSE_PWD);
imx233_lradc_clear_channel(nmos_chan);
imx233_lradc_clear_channel(pmos_chan);
// schedule both channels
imx233_lradc_kick_channel(nmos_chan);
imx233_lradc_kick_channel(pmos_chan);
// wait completion
imx233_lradc_wait_channel(nmos_chan);
imx233_lradc_wait_channel(pmos_chan);
// mux sensors
BF_SET(LRADC_CTRL2, TEMPSENSE_PWD);
// do the computation
int diff = imx233_lradc_read_channel(nmos_chan) - imx233_lradc_read_channel(pmos_chan);
// return diff * 1.012 / 4
return (diff * 1012) / 4000;
}
#endif
/* set to 0 to disable current source */
static void imx233_lradc_set_temp_isrc(int sensor, int value)
{
if(sensor < 0 || sensor > 1)
panicf("imx233_lradc_set_temp_isrc: invalid sensor");
unsigned mask = sensor ? BM_LRADC_CTRL2_TEMP_ISRC0 : BM_LRADC_CTRL2_TEMP_ISRC1;
unsigned bp = sensor ? BP_LRADC_CTRL2_TEMP_ISRC0 : BP_LRADC_CTRL2_TEMP_ISRC1;
unsigned en = sensor ? BM_LRADC_CTRL2_TEMP_SENSOR_IENABLE0 : BM_LRADC_CTRL2_TEMP_SENSOR_IENABLE1;
HW_LRADC_CTRL2_CLR = mask;
HW_LRADC_CTRL2_SET = value << bp;
if(value != 0)
{
HW_LRADC_CTRL2_SET = en;
udelay(100);
}
else
HW_LRADC_CTRL2_CLR = en;
}
int imx233_lradc_sense_ext_temperature(int chan, int sensor)
{
#define EXT_TEMP_ACC_COUNT 5
/* setup channel */
imx233_lradc_setup_channel(chan, false, false, 0, sensor);
/* set current source to 300µA */
imx233_lradc_set_temp_isrc(sensor, BV_LRADC_CTRL2_TEMP_ISRC0__300);
/* read value and accumulate */
int a = 0;
for(int i = 0; i < EXT_TEMP_ACC_COUNT; i++)
{
imx233_lradc_clear_channel(chan);
imx233_lradc_kick_channel(chan);
imx233_lradc_wait_channel(chan);
a += imx233_lradc_read_channel(chan);
}
/* setup channel for small accumulation */
/* set current source to 20µA */
imx233_lradc_set_temp_isrc(sensor, BV_LRADC_CTRL2_TEMP_ISRC0__20);
/* read value */
int b = 0;
for(int i = 0; i < EXT_TEMP_ACC_COUNT; i++)
{
imx233_lradc_clear_channel(chan);
imx233_lradc_kick_channel(chan);
imx233_lradc_wait_channel(chan);
b += imx233_lradc_read_channel(chan);
}
/* disable sensor current */
imx233_lradc_set_temp_isrc(sensor, BV_LRADC_CTRL2_TEMP_ISRC0__ZERO);
return (abs(b - a) / EXT_TEMP_ACC_COUNT) * 1104 / 1000;
}
void imx233_lradc_setup_battery_conversion(bool automatic, unsigned long scale_factor)
{
BF_CLR(LRADC_CONVERSION, SCALE_FACTOR);
BF_SETV(LRADC_CONVERSION, SCALE_FACTOR, scale_factor);
if(automatic)
BF_SET(LRADC_CONVERSION, AUTOMATIC);
else
BF_CLR(LRADC_CONVERSION, AUTOMATIC);
}
int imx233_lradc_read_battery_voltage(void)
{
return BF_RD(LRADC_CONVERSION, SCALED_BATT_VOLTAGE);
}
void imx233_lradc_setup_touch(bool xminus_enable, bool yminus_enable,
bool xplus_enable, bool yplus_enable, bool touch_detect)
{
HW_LRADC_CTRL0_CLR = BM_OR5(LRADC_CTRL0, XMINUS_ENABLE, YMINUS_ENABLE,
XPLUS_ENABLE, YPLUS_ENABLE, TOUCH_DETECT_ENABLE);
HW_LRADC_CTRL0_SET = BF_OR5(LRADC_CTRL0, XMINUS_ENABLE(xminus_enable),
YMINUS_ENABLE(yminus_enable), XPLUS_ENABLE(xplus_enable),
YPLUS_ENABLE(yplus_enable), TOUCH_DETECT_ENABLE(touch_detect));
}
void imx233_lradc_enable_touch_detect_irq(bool enable)
{
if(enable)
BF_SET(LRADC_CTRL1, TOUCH_DETECT_IRQ_EN);
else
BF_CLR(LRADC_CTRL1, TOUCH_DETECT_IRQ_EN);
imx233_lradc_clear_touch_detect_irq();
}
void imx233_lradc_clear_touch_detect_irq(void)
{
BF_CLR(LRADC_CTRL1, TOUCH_DETECT_IRQ);
}
bool imx233_lradc_read_touch_detect(void)
{
return BF_RD(LRADC_STATUS, TOUCH_DETECT_RAW);
}
void imx233_lradc_init(void)
{
/* On STMP3700+, any channel can measure any source but on STMP3600 only
* channels 6 and 7 can measure all sources. Channel 7 being dedicated to
* battery, only channel 6 is available for free use */
#if IMX233_SUBTARGET >= 3700
arbiter_init(&channel_arbiter, LRADC_NUM_CHANNELS);
#else
for(int i = 0; i < LRADC_NUM_CHANNELS; i++)
semaphore_init(&channel_sema[i], 1, 1);
#endif
arbiter_init(&delay_arbiter, LRADC_NUM_DELAYS);
// enable block
imx233_reset_block(&HW_LRADC_CTRL0);
// disable ground ref
BF_CLR(LRADC_CTRL0, ONCHIP_GROUNDREF);
// disable temperature sensors
BF_CLR(LRADC_CTRL2, TEMP_SENSOR_IENABLE0);
BF_CLR(LRADC_CTRL2, TEMP_SENSOR_IENABLE1);
#if IMX233_SUBTARGET >= 3700
BF_SET(LRADC_CTRL2, TEMPSENSE_PWD);
#endif
// set frequency
BF_CLR(LRADC_CTRL3, CYCLE_TIME);
BF_SETV(LRADC_CTRL3, CYCLE_TIME_V, 6MHZ);
// setup battery
battery_chan = 7;
imx233_lradc_reserve_channel(battery_chan);
/* setup them for the simplest use: no accumulation, no division*/
imx233_lradc_setup_channel(battery_chan, false, false, 0, LRADC_SRC_BATTERY);
/* setup delay channel for battery for automatic reading and scaling */
battery_delay_chan = 0;
imx233_lradc_reserve_delay(battery_delay_chan);
/* setup delay to trigger battery channel and retrigger itself.
* The counter runs at 2KHz so a delay of 200 will trigger 10
* conversions per seconds */
imx233_lradc_setup_delay(battery_delay_chan, 1 << battery_chan,
1 << battery_delay_chan, 0, 200);
imx233_lradc_kick_delay(battery_delay_chan);
/* enable automatic conversion, use Li-Ion type battery */
imx233_lradc_setup_battery_conversion(true, BV_LRADC_CONVERSION_SCALE_FACTOR__LI_ION);
}