xref: /netbsd-src/sys/dev/i2c/fan53555.c (revision f3cfa6f6ce31685c6c4a758bc430e69eb99f50a4)
1 /* $NetBSD: fan53555.c,v 1.2 2018/08/29 11:08:30 jmcneill Exp $ */
2 
3 /*-
4  * Copyright (c) 2018 Jared McNeill <jmcneill@invisible.ca>
5  * All rights reserved.
6  *
7  * Redistribution and use in source and binary forms, with or without
8  * modification, are permitted provided that the following conditions
9  * are met:
10  * 1. Redistributions of source code must retain the above copyright
11  *    notice, this list of conditions and the following disclaimer.
12  * 2. Redistributions in binary form must reproduce the above copyright
13  *    notice, this list of conditions and the following disclaimer in the
14  *    documentation and/or other materials provided with the distribution.
15  *
16  * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS
17  * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
18  * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
19  * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS
20  * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
21  * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
22  * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
23  * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
24  * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
25  * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
26  * POSSIBILITY OF SUCH DAMAGE.
27  */
28 
29 #include <sys/cdefs.h>
30 __KERNEL_RCSID(0, "$NetBSD: fan53555.c,v 1.2 2018/08/29 11:08:30 jmcneill Exp $");
31 
32 #include <sys/param.h>
33 #include <sys/systm.h>
34 #include <sys/kernel.h>
35 #include <sys/device.h>
36 #include <sys/conf.h>
37 #include <sys/bus.h>
38 #include <sys/kmem.h>
39 
40 #include <dev/i2c/i2cvar.h>
41 
42 #include <dev/fdt/fdtvar.h>
43 
44 #define	VSEL0_REG		0x00
45 #define	VSEL1_REG		0x01
46 #define	 VSEL_BUCK_EN			__BIT(7)
47 #define	 VSEL_MODE			__BIT(6)
48 #define	 VSEL_NSEL			__BITS(5,0)
49 #define	CONTROL_REG		0x02
50 #define	 CONTROL_OUTPUT_DISCHARGE	__BIT(7)
51 #define	 CONTROL_SLEW			__BITS(6,4)
52 #define	 CONTROL_RESET			__BIT(2)
53 #define	ID1_REG			0x03
54 #define	 ID1_VENDOR			__BITS(7,5)
55 #define	 ID1_DIE_ID			__BITS(3,0)
56 #define	  SILERGY_DIE_ID_SYR82X		8
57 #define	ID2_REG			0x04
58 #define	 ID2_DIE_REV			__BITS(3,0)
59 #define	MONITOR_REG		0x05
60 #define	 MONITOR_PGOOD			__BIT(7)
61 
62 struct fan53555_softc {
63 	device_t	sc_dev;
64 	i2c_tag_t	sc_i2c;
65 	i2c_addr_t	sc_addr;
66 	int		sc_phandle;
67 
68 	u_int		sc_suspend_reg;
69 	u_int		sc_runtime_reg;
70 
71 	u_int		sc_base;
72 	u_int		sc_step;
73 
74 	u_int		sc_ramp_delay;
75 	u_int		sc_suspend_voltage_selector;
76 };
77 
78 enum fan53555_vendor {
79 	FAN_VENDOR_FAIRCHILD = 1,
80 	FAN_VENDOR_SILERGY,
81 };
82 
83 /*
84  * Transition slew rates.
85  * Array index is reg value, value is slew rate in uV / us
86  */
87 static const int fan53555_slew_rates[] = {
88 	64000, 32000, 16000, 8000, 4000, 2000, 1000, 500
89 };
90 
91 static const struct device_compatible_entry compat_data[] = {
92 	{ "silergy,syr827",		FAN_VENDOR_SILERGY },
93 	{ "silergy,syr828",		FAN_VENDOR_SILERGY },
94 	{ NULL,				0 }
95 };
96 
97 static uint8_t
98 fan53555_read(struct fan53555_softc *sc, uint8_t reg, int flags)
99 {
100 	uint8_t val = 0;
101 	int error;
102 
103 	error = iic_exec(sc->sc_i2c, I2C_OP_READ_WITH_STOP, sc->sc_addr,
104 	    &reg, 1, &val, 1, flags);
105 	if (error != 0)
106 		aprint_error_dev(sc->sc_dev, "error reading reg %#x: %d\n", reg, error);
107 
108 	return val;
109 }
110 
111 static void
112 fan53555_write(struct fan53555_softc *sc, uint8_t reg, uint8_t val, int flags)
113 {
114 	uint8_t buf[2];
115 	int error;
116 
117 	buf[0] = reg;
118 	buf[1] = val;
119 
120 	error = iic_exec(sc->sc_i2c, I2C_OP_WRITE_WITH_STOP, sc->sc_addr,
121 	    NULL, 0, buf, 2, flags);
122 	if (error != 0)
123 		aprint_error_dev(sc->sc_dev, "error writing reg %#x: %d\n", reg, error);
124 }
125 
126 #define	I2C_READ(sc, reg)	fan53555_read((sc), (reg), I2C_F_POLL)
127 #define	I2C_WRITE(sc, reg, val)	fan53555_write((sc), (reg), (val), I2C_F_POLL)
128 #define	I2C_LOCK(sc)		iic_acquire_bus((sc)->sc_i2c, I2C_F_POLL)
129 #define	I2C_UNLOCK(sc)		iic_release_bus((sc)->sc_i2c, I2C_F_POLL)
130 
131 static int
132 fan53555_acquire(device_t dev)
133 {
134 	return 0;
135 }
136 
137 static void
138 fan53555_release(device_t dev)
139 {
140 }
141 
142 static int
143 fan53555_enable(device_t dev, bool enable)
144 {
145 	struct fan53555_softc * const sc = device_private(dev);
146 	uint8_t val;
147 
148 	I2C_LOCK(sc);
149 	val = I2C_READ(sc, sc->sc_runtime_reg);
150 	if (enable)
151 		val |= VSEL_BUCK_EN;
152 	else
153 		val &= ~VSEL_BUCK_EN;
154 	I2C_WRITE(sc, sc->sc_runtime_reg, val);
155 	I2C_UNLOCK(sc);
156 
157 	if (sc->sc_ramp_delay)
158 		delay(sc->sc_ramp_delay);
159 
160 	return 0;
161 }
162 
163 static int
164 fan53555_set_voltage(device_t dev, u_int min_uvol, u_int max_uvol)
165 {
166 	struct fan53555_softc * const sc = device_private(dev);
167 	uint8_t val, oval;
168 	u_int cur_uvol;
169 
170 	I2C_LOCK(sc);
171 
172 	/* Get current voltage */
173 	oval = I2C_READ(sc, sc->sc_runtime_reg);
174 	cur_uvol = __SHIFTOUT(oval, VSEL_NSEL) * sc->sc_step + sc->sc_base;
175 
176 	/* Set new voltage */
177 	val = oval & ~VSEL_NSEL;
178 	val |= __SHIFTIN((min_uvol - sc->sc_base) / sc->sc_step, VSEL_NSEL);
179 	I2C_WRITE(sc, sc->sc_runtime_reg, val);
180 
181 	I2C_UNLOCK(sc);
182 
183 	/* Time to delay is based on the number of voltage steps */
184 	if (sc->sc_ramp_delay)
185 		delay((abs(cur_uvol - min_uvol) / sc->sc_step) * sc->sc_ramp_delay);
186 
187 	return 0;
188 }
189 
190 static int
191 fan53555_get_voltage(device_t dev, u_int *puvol)
192 {
193 	struct fan53555_softc * const sc = device_private(dev);
194 	uint8_t val;
195 
196 	I2C_LOCK(sc);
197 	val = I2C_READ(sc, sc->sc_runtime_reg);
198 	I2C_UNLOCK(sc);
199 
200 	*puvol = __SHIFTOUT(val, VSEL_NSEL) * sc->sc_step + sc->sc_base;
201 
202 	return 0;
203 }
204 
205 static struct fdtbus_regulator_controller_func fan53555_funcs = {
206 	.acquire = fan53555_acquire,
207 	.release = fan53555_release,
208 	.enable = fan53555_enable,
209 	.set_voltage = fan53555_set_voltage,
210 	.get_voltage = fan53555_get_voltage,
211 };
212 
213 static int
214 fan53555_init(struct fan53555_softc *sc, enum fan53555_vendor vendor)
215 {
216 	uint8_t id1, control;
217 	int n;
218 
219 	I2C_LOCK(sc);
220 	id1 = I2C_READ(sc, ID1_REG);
221 	I2C_UNLOCK(sc);
222 
223 	const u_int die_id = __SHIFTOUT(id1, ID1_DIE_ID);
224 
225 	aprint_naive("\n");
226 	switch (vendor) {
227 	case FAN_VENDOR_SILERGY:
228 		switch (die_id) {
229 		case SILERGY_DIE_ID_SYR82X:
230 			aprint_normal(": Silergy SYR82X\n");
231 			sc->sc_base = 712500;
232 			sc->sc_step = 12500;
233 			break;
234 		default:
235 			aprint_error(": Unsupported Silergy chip (0x%x)\n", die_id);
236 			return ENXIO;
237 		}
238 		break;
239 	default:
240 		aprint_error(": Unsupported vendor (%d)\n", vendor);
241 		return ENXIO;
242 	}
243 
244 	of_getprop_uint32(sc->sc_phandle, "suspend_voltage_selector",
245 	    &sc->sc_suspend_voltage_selector);
246 	switch (sc->sc_suspend_voltage_selector) {
247 	case 0:
248 		sc->sc_suspend_reg = VSEL0_REG;
249 		sc->sc_runtime_reg = VSEL1_REG;
250 		break;
251 	case 1:
252 		sc->sc_suspend_reg = VSEL1_REG;
253 		sc->sc_runtime_reg = VSEL0_REG;
254 		break;
255 	default:
256 		aprint_error_dev(sc->sc_dev, "unsupported 'fcs,suspend-voltage-selector' value %u\n", sc->sc_suspend_voltage_selector);
257 		return EINVAL;
258 	}
259 
260 	of_getprop_uint32(sc->sc_phandle, "regulator-ramp-delay",
261 	    &sc->sc_ramp_delay);
262 	if (sc->sc_ramp_delay) {
263 		for (n = 0; n < __arraycount(fan53555_slew_rates); n++)
264 			if (sc->sc_ramp_delay > fan53555_slew_rates[n])
265 				break;
266 		if (n == __arraycount(fan53555_slew_rates)) {
267 			aprint_error_dev(sc->sc_dev, "unsupported 'regulator-ramp-delay' value %u\n", sc->sc_ramp_delay);
268 			return EINVAL;
269 		}
270 		I2C_LOCK(sc);
271 		control = I2C_READ(sc, CONTROL_REG);
272 		control &= ~CONTROL_SLEW;
273 		control |= __SHIFTIN(fan53555_slew_rates[n], CONTROL_SLEW);
274 		I2C_WRITE(sc, CONTROL_REG, control);
275 		I2C_UNLOCK(sc);
276 	}
277 
278 	return 0;
279 }
280 
281 static int
282 fan53555_match(device_t parent, cfdata_t match, void *aux)
283 {
284 	struct i2c_attach_args *ia = aux;
285 	int match_result;
286 
287 	if (iic_use_direct_match(ia, match, compat_data, &match_result))
288 		return match_result;
289 
290 	return 0;
291 }
292 
293 static void
294 fan53555_attach(device_t parent, device_t self, void *aux)
295 {
296 	struct fan53555_softc * const sc = device_private(self);
297 	const struct device_compatible_entry *compat;
298 	struct i2c_attach_args *ia = aux;
299 
300 	sc->sc_dev = self;
301 	sc->sc_i2c = ia->ia_tag;
302 	sc->sc_addr = ia->ia_addr;
303 	sc->sc_phandle = ia->ia_cookie;
304 
305 	iic_compatible_match(ia, compat_data, &compat);
306 
307 	if (fan53555_init(sc, compat->data) != 0)
308 		return;
309 
310 	fdtbus_register_regulator_controller(self, sc->sc_phandle,
311 	    &fan53555_funcs);
312 }
313 
314 CFATTACH_DECL_NEW(fan53555reg, sizeof(struct fan53555_softc),
315     fan53555_match, fan53555_attach, NULL, NULL);
316