freebsd-dev/sys/arm/freescale/vybrid/vf_adc.c
2016-11-14 11:41:22 +00:00

244 lines
7.3 KiB
C

/*-
* Copyright (c) 2014 Ruslan Bukin <br@bsdpad.com>
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
*
* THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
* ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
* SUCH DAMAGE.
*/
/*
* Vybrid Family 12-bit Analog to Digital Converter (ADC)
* Chapter 37, Vybrid Reference Manual, Rev. 5, 07/2013
*/
#include <sys/cdefs.h>
__FBSDID("$FreeBSD$");
#include <sys/param.h>
#include <sys/systm.h>
#include <sys/bus.h>
#include <sys/kernel.h>
#include <sys/module.h>
#include <sys/malloc.h>
#include <sys/rman.h>
#include <sys/timeet.h>
#include <sys/timetc.h>
#include <dev/ofw/openfirm.h>
#include <dev/ofw/ofw_bus.h>
#include <dev/ofw/ofw_bus_subr.h>
#include <machine/bus.h>
#include <machine/cpu.h>
#include <machine/intr.h>
#include <arm/freescale/vybrid/vf_common.h>
#include <arm/freescale/vybrid/vf_adc.h>
#define ADC_HC0 0x00 /* Ctrl reg for hardware triggers */
#define ADC_HC1 0x04 /* Ctrl reg for hardware triggers */
#define HC_AIEN (1 << 7) /* Conversion Complete Int Control */
#define HC_ADCH_M 0x1f /* Input Channel Select Mask */
#define HC_ADCH_S 0 /* Input Channel Select Shift */
#define ADC_HS 0x08 /* Status register for HW triggers */
#define HS_COCO0 (1 << 0) /* Conversion Complete Flag */
#define HS_COCO1 (1 << 1) /* Conversion Complete Flag */
#define ADC_R0 0x0C /* Data result reg for HW triggers */
#define ADC_R1 0x10 /* Data result reg for HW triggers */
#define ADC_CFG 0x14 /* Configuration register */
#define CFG_OVWREN (1 << 16) /* Data Overwrite Enable */
#define CFG_AVGS_M 0x3 /* Hardware Average select Mask */
#define CFG_AVGS_S 14 /* Hardware Average select Shift */
#define CFG_ADTRG (1 << 13) /* Conversion Trigger Select */
#define CFG_REFSEL_M 0x3 /* Voltage Reference Select Mask */
#define CFG_REFSEL_S 11 /* Voltage Reference Select Shift */
#define CFG_ADHSC (1 << 10) /* High Speed Configuration */
#define CFG_ADSTS_M 0x3 /* Defines the sample time duration */
#define CFG_ADSTS_S 8 /* Defines the sample time duration */
#define CFG_ADLPC (1 << 7) /* Low-Power Configuration */
#define CFG_ADIV_M 0x3 /* Clock Divide Select */
#define CFG_ADIV_S 5 /* Clock Divide Select */
#define CFG_ADLSMP (1 << 4) /* Long Sample Time Configuration */
#define CFG_MODE_M 0x3 /* Conversion Mode Selection Mask */
#define CFG_MODE_S 2 /* Conversion Mode Selection Shift */
#define CFG_MODE_12 0x2 /* 12-bit mode */
#define CFG_ADICLK_M 0x3 /* Input Clock Select Mask */
#define CFG_ADICLK_S 0 /* Input Clock Select Shift */
#define ADC_GC 0x18 /* General control register */
#define GC_CAL (1 << 7) /* Calibration */
#define GC_ADCO (1 << 6) /* Continuous Conversion Enable */
#define GC_AVGE (1 << 5) /* Hardware average enable */
#define GC_ACFE (1 << 4) /* Compare Function Enable */
#define GC_ACFGT (1 << 3) /* Compare Function Greater Than En */
#define GC_ACREN (1 << 2) /* Compare Function Range En */
#define GC_DMAEN (1 << 1) /* DMA Enable */
#define GC_ADACKEN (1 << 0) /* Asynchronous clock output enable */
#define ADC_GS 0x1C /* General status register */
#define GS_AWKST (1 << 2) /* Asynchronous wakeup int status */
#define GS_CALF (1 << 1) /* Calibration Failed Flag */
#define GS_ADACT (1 << 0) /* Conversion Active */
#define ADC_CV 0x20 /* Compare value register */
#define CV_CV2_M 0xfff /* Compare Value 2 Mask */
#define CV_CV2_S 16 /* Compare Value 2 Shift */
#define CV_CV1_M 0xfff /* Compare Value 1 Mask */
#define CV_CV1_S 0 /* Compare Value 1 Shift */
#define ADC_OFS 0x24 /* Offset correction value register */
#define OFS_SIGN 12 /* Sign bit */
#define OFS_M 0xfff /* Offset value Mask */
#define OFS_S 0 /* Offset value Shift */
#define ADC_CAL 0x28 /* Calibration value register */
#define CAL_CODE_M 0xf /* Calibration Result Value Mask */
#define CAL_CODE_S 0 /* Calibration Result Value Shift */
#define ADC_PCTL 0x30 /* Pin control register */
struct adc_softc {
struct resource *res[2];
bus_space_tag_t bst;
bus_space_handle_t bsh;
void *ih;
};
struct adc_softc *adc_sc;
static struct resource_spec adc_spec[] = {
{ SYS_RES_MEMORY, 0, RF_ACTIVE },
{ SYS_RES_IRQ, 0, RF_ACTIVE },
{ -1, 0 }
};
static int
adc_probe(device_t dev)
{
if (!ofw_bus_status_okay(dev))
return (ENXIO);
if (!ofw_bus_is_compatible(dev, "fsl,mvf600-adc"))
return (ENXIO);
device_set_desc(dev, "Vybrid Family "
"12-bit Analog to Digital Converter");
return (BUS_PROBE_DEFAULT);
}
static void
adc_intr(void *arg)
{
struct adc_softc *sc;
sc = arg;
/* Conversation complete */
}
uint32_t
adc_read(void)
{
struct adc_softc *sc;
sc = adc_sc;
if (sc == NULL)
return (0);
return (READ4(sc, ADC_R0));
}
uint32_t
adc_enable(int channel)
{
struct adc_softc *sc;
int reg;
sc = adc_sc;
if (sc == NULL)
return (1);
reg = READ4(sc, ADC_HC0);
reg &= ~(HC_ADCH_M << HC_ADCH_S);
reg |= (channel << HC_ADCH_S);
WRITE4(sc, ADC_HC0, reg);
return (0);
}
static int
adc_attach(device_t dev)
{
struct adc_softc *sc;
int err;
int reg;
sc = device_get_softc(dev);
if (bus_alloc_resources(dev, adc_spec, sc->res)) {
device_printf(dev, "could not allocate resources\n");
return (ENXIO);
}
/* Memory interface */
sc->bst = rman_get_bustag(sc->res[0]);
sc->bsh = rman_get_bushandle(sc->res[0]);
adc_sc = sc;
/* Setup interrupt handler */
err = bus_setup_intr(dev, sc->res[1], INTR_TYPE_BIO | INTR_MPSAFE,
NULL, adc_intr, sc, &sc->ih);
if (err) {
device_printf(dev, "Unable to alloc interrupt resource.\n");
return (ENXIO);
}
/* Configure 12-bit mode */
reg = READ4(sc, ADC_CFG);
reg &= ~(CFG_MODE_M << CFG_MODE_S);
reg |= (CFG_MODE_12 << CFG_MODE_S); /* 12bit */
WRITE4(sc, ADC_CFG, reg);
/* Configure for continuous conversion */
reg = READ4(sc, ADC_GC);
reg |= (GC_ADCO | GC_AVGE);
WRITE4(sc, ADC_GC, reg);
/* Disable interrupts */
reg = READ4(sc, ADC_HC0);
reg &= HC_AIEN;
WRITE4(sc, ADC_HC0, reg);
return (0);
}
static device_method_t adc_methods[] = {
DEVMETHOD(device_probe, adc_probe),
DEVMETHOD(device_attach, adc_attach),
{ 0, 0 }
};
static driver_t adc_driver = {
"adc",
adc_methods,
sizeof(struct adc_softc),
};
static devclass_t adc_devclass;
DRIVER_MODULE(adc, simplebus, adc_driver, adc_devclass, 0, 0);