1/*-
2 * Copyright (c) 2014 Ruslan Bukin <br@bsdpad.com>
3 * All rights reserved.
4 *
5 * Redistribution and use in source and binary forms, with or without
6 * modification, are permitted provided that the following conditions
7 * are met:
8 * 1. Redistributions of source code must retain the above copyright
9 *    notice, this list of conditions and the following disclaimer.
10 * 2. Redistributions in binary form must reproduce the above copyright
11 *    notice, this list of conditions and the following disclaimer in the
12 *    documentation and/or other materials provided with the distribution.
13 *
14 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
15 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
16 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
17 * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
18 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
19 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
20 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
21 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
22 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
23 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
24 * SUCH DAMAGE.
25 */
26
27/*
28 * Vybrid Family 12-bit Analog to Digital Converter (ADC)
29 * Chapter 37, Vybrid Reference Manual, Rev. 5, 07/2013
30 */
31
32#include <sys/cdefs.h>
33__FBSDID("$FreeBSD$");
34
35#include <sys/param.h>
36#include <sys/systm.h>
37#include <sys/bus.h>
38#include <sys/kernel.h>
39#include <sys/module.h>
40#include <sys/malloc.h>
41#include <sys/rman.h>
42#include <sys/timeet.h>
43#include <sys/timetc.h>
44
45#include <dev/ofw/openfirm.h>
46#include <dev/ofw/ofw_bus.h>
47#include <dev/ofw/ofw_bus_subr.h>
48
49#include <machine/bus.h>
50#include <machine/cpu.h>
51#include <machine/intr.h>
52
53#include <arm/freescale/vybrid/vf_common.h>
54#include <arm/freescale/vybrid/vf_adc.h>
55
56#define	ADC_HC0		0x00		/* Ctrl reg for hardware triggers */
57#define	ADC_HC1		0x04		/* Ctrl reg for hardware triggers */
58#define	 HC_AIEN	(1 << 7)	/* Conversion Complete Int Control */
59#define	 HC_ADCH_M	0x1f		/* Input Channel Select Mask */
60#define	 HC_ADCH_S	0		/* Input Channel Select Shift */
61#define	ADC_HS		0x08		/* Status register for HW triggers */
62#define	 HS_COCO0	(1 << 0)	/* Conversion Complete Flag */
63#define	 HS_COCO1	(1 << 1)	/* Conversion Complete Flag */
64#define	ADC_R0		0x0C		/* Data result reg for HW triggers */
65#define	ADC_R1		0x10		/* Data result reg for HW triggers */
66#define	ADC_CFG		0x14		/* Configuration register */
67#define	 CFG_OVWREN	(1 << 16)	/* Data Overwrite Enable */
68#define	 CFG_AVGS_M	0x3		/* Hardware Average select Mask */
69#define	 CFG_AVGS_S	14		/* Hardware Average select Shift */
70#define	 CFG_ADTRG	(1 << 13)	/* Conversion Trigger Select */
71#define	 CFG_REFSEL_M	0x3		/* Voltage Reference Select Mask */
72#define	 CFG_REFSEL_S	11		/* Voltage Reference Select Shift */
73#define	 CFG_ADHSC	(1 << 10)	/* High Speed Configuration */
74#define	 CFG_ADSTS_M	0x3		/* Defines the sample time duration */
75#define	 CFG_ADSTS_S	8		/* Defines the sample time duration */
76#define	 CFG_ADLPC	(1 << 7)	/* Low-Power Configuration */
77#define	 CFG_ADIV_M	0x3		/* Clock Divide Select */
78#define	 CFG_ADIV_S	5		/* Clock Divide Select */
79#define	 CFG_ADLSMP	(1 << 4)	/* Long Sample Time Configuration */
80#define	 CFG_MODE_M	0x3		/* Conversion Mode Selection Mask */
81#define	 CFG_MODE_S	2		/* Conversion Mode Selection Shift */
82#define	 CFG_MODE_12	0x2		/* 12-bit mode */
83#define	 CFG_ADICLK_M	0x3		/* Input Clock Select Mask */
84#define	 CFG_ADICLK_S	0		/* Input Clock Select Shift */
85#define	ADC_GC		0x18		/* General control register */
86#define	 GC_CAL		(1 << 7)	/* Calibration */
87#define	 GC_ADCO	(1 << 6)	/* Continuous Conversion Enable */
88#define	 GC_AVGE	(1 << 5)	/* Hardware average enable */
89#define	 GC_ACFE	(1 << 4)	/* Compare Function Enable */
90#define	 GC_ACFGT	(1 << 3)	/* Compare Function Greater Than En */
91#define	 GC_ACREN	(1 << 2)	/* Compare Function Range En */
92#define	 GC_DMAEN	(1 << 1)	/* DMA Enable */
93#define	 GC_ADACKEN	(1 << 0)	/* Asynchronous clock output enable */
94#define	ADC_GS		0x1C		/* General status register */
95#define	 GS_AWKST	(1 << 2)	/* Asynchronous wakeup int status */
96#define	 GS_CALF	(1 << 1)	/* Calibration Failed Flag */
97#define	 GS_ADACT	(1 << 0)	/* Conversion Active */
98#define	ADC_CV		0x20		/* Compare value register */
99#define	 CV_CV2_M	0xfff		/* Compare Value 2 Mask */
100#define	 CV_CV2_S	16		/* Compare Value 2 Shift */
101#define	 CV_CV1_M	0xfff		/* Compare Value 1 Mask */
102#define	 CV_CV1_S	0		/* Compare Value 1 Shift */
103#define	ADC_OFS		0x24		/* Offset correction value register */
104#define	 OFS_SIGN	12		/* Sign bit */
105#define	 OFS_M		0xfff		/* Offset value Mask */
106#define	 OFS_S		0		/* Offset value Shift */
107#define	ADC_CAL		0x28		/* Calibration value register */
108#define	 CAL_CODE_M	0xf		/* Calibration Result Value Mask */
109#define	 CAL_CODE_S	0		/* Calibration Result Value Shift */
110#define	ADC_PCTL	0x30		/* Pin control register */
111
112struct adc_softc {
113	struct resource		*res[2];
114	bus_space_tag_t		bst;
115	bus_space_handle_t	bsh;
116	void			*ih;
117};
118
119struct adc_softc *adc_sc;
120
121static struct resource_spec adc_spec[] = {
122	{ SYS_RES_MEMORY,	0,	RF_ACTIVE },
123	{ SYS_RES_IRQ,		0,	RF_ACTIVE },
124	{ -1, 0 }
125};
126
127static int
128adc_probe(device_t dev)
129{
130
131	if (!ofw_bus_status_okay(dev))
132		return (ENXIO);
133
134	if (!ofw_bus_is_compatible(dev, "fsl,mvf600-adc"))
135		return (ENXIO);
136
137	device_set_desc(dev, "Vybrid Family "
138	    "12-bit Analog to Digital Converter");
139	return (BUS_PROBE_DEFAULT);
140}
141
142static void
143adc_intr(void *arg)
144{
145	struct adc_softc *sc;
146
147	sc = arg;
148
149	/* Conversation complete */
150}
151
152uint32_t
153adc_read(void)
154{
155	struct adc_softc *sc;
156
157	sc = adc_sc;
158	if (sc == NULL)
159		return (0);
160
161	return (READ4(sc, ADC_R0));
162}
163
164uint32_t
165adc_enable(int channel)
166{
167	struct adc_softc *sc;
168	int reg;
169
170	sc = adc_sc;
171	if (sc == NULL)
172		return (1);
173
174	reg = READ4(sc, ADC_HC0);
175	reg &= ~(HC_ADCH_M << HC_ADCH_S);
176	reg |= (channel << HC_ADCH_S);
177	WRITE4(sc, ADC_HC0, reg);
178
179	return (0);
180}
181
182static int
183adc_attach(device_t dev)
184{
185	struct adc_softc *sc;
186	int err;
187	int reg;
188
189	sc = device_get_softc(dev);
190
191	if (bus_alloc_resources(dev, adc_spec, sc->res)) {
192		device_printf(dev, "could not allocate resources\n");
193		return (ENXIO);
194	}
195
196	/* Memory interface */
197	sc->bst = rman_get_bustag(sc->res[0]);
198	sc->bsh = rman_get_bushandle(sc->res[0]);
199
200	adc_sc = sc;
201
202	/* Setup interrupt handler */
203	err = bus_setup_intr(dev, sc->res[1], INTR_TYPE_BIO | INTR_MPSAFE,
204	    NULL, adc_intr, sc, &sc->ih);
205	if (err) {
206		device_printf(dev, "Unable to alloc interrupt resource.\n");
207		return (ENXIO);
208	}
209
210	/* Configure 12-bit mode */
211	reg = READ4(sc, ADC_CFG);
212	reg &= ~(CFG_MODE_M << CFG_MODE_S);
213	reg |= (CFG_MODE_12 << CFG_MODE_S); /* 12bit */
214	WRITE4(sc, ADC_CFG, reg);
215
216	/* Configure for continuous conversion */
217	reg = READ4(sc, ADC_GC);
218	reg |= (GC_ADCO | GC_AVGE);
219	WRITE4(sc, ADC_GC, reg);
220
221	/* Disable interrupts */
222	reg = READ4(sc, ADC_HC0);
223	reg &= HC_AIEN;
224	WRITE4(sc, ADC_HC0, reg);
225
226	return (0);
227}
228
229static device_method_t adc_methods[] = {
230	DEVMETHOD(device_probe,		adc_probe),
231	DEVMETHOD(device_attach,	adc_attach),
232	{ 0, 0 }
233};
234
235static driver_t adc_driver = {
236	"adc",
237	adc_methods,
238	sizeof(struct adc_softc),
239};
240
241static devclass_t adc_devclass;
242
243DRIVER_MODULE(adc, simplebus, adc_driver, adc_devclass, 0, 0);
244