max77620.c revision 1.9
1 /* $NetBSD: max77620.c,v 1.9 2021/01/17 21:42:35 thorpej Exp $ */ 2 3 /*- 4 * Copyright (c) 2017 Jared McNeill <jmcneill (at) 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: max77620.c,v 1.9 2021/01/17 21:42:35 thorpej Exp $"); 31 32 #include <sys/param.h> 33 #include <sys/systm.h> 34 #include <sys/mutex.h> 35 #include <sys/kernel.h> 36 #include <sys/device.h> 37 #include <sys/conf.h> 38 #include <sys/bus.h> 39 #include <sys/kmem.h> 40 #include <sys/gpio.h> 41 42 #include <dev/i2c/i2cvar.h> 43 44 #include <dev/fdt/fdtvar.h> 45 46 #define MAX_GPIO_REG(n) (0x36 + (n)) 47 #define MAX_GPIO_DEBOUNCE __BITS(7,6) 48 #define MAX_GPIO_INT __BITS(5,4) 49 #define MAX_GPIO_OUTPUT_VAL __BIT(3) 50 #define MAX_GPIO_INPUT_VAL __BIT(2) 51 #define MAX_GPIO_DIR __BIT(1) 52 #define MAX_GPIO_DRV __BIT(0) 53 54 #define MAX_GPIO_COUNT 8 55 56 struct max77620_softc { 57 device_t sc_dev; 58 i2c_tag_t sc_i2c; 59 i2c_addr_t sc_addr; 60 int sc_phandle; 61 }; 62 63 struct max77620_pin { 64 struct max77620_softc *pin_sc; 65 int pin_num; 66 int pin_flags; 67 bool pin_actlo; 68 }; 69 70 static const struct device_compatible_entry compat_data[] = { 71 { .compat = "maxim,max77620" }, 72 73 { 0 } 74 }; 75 76 static uint8_t 77 max77620_read(struct max77620_softc *sc, uint8_t reg, int flags) 78 { 79 uint8_t val = 0; 80 int error; 81 82 error = iic_exec(sc->sc_i2c, I2C_OP_READ_WITH_STOP, sc->sc_addr, 83 ®, 1, &val, 1, flags); 84 if (error != 0) 85 aprint_error_dev(sc->sc_dev, "error reading reg %#x: %d\n", reg, error); 86 87 return val; 88 } 89 90 static void 91 max77620_write(struct max77620_softc *sc, uint8_t reg, uint8_t val, int flags) 92 { 93 int error; 94 95 error = iic_exec(sc->sc_i2c, I2C_OP_WRITE_WITH_STOP, sc->sc_addr, 96 ®, 1, &val, 1, flags); 97 if (error != 0) 98 aprint_error_dev(sc->sc_dev, "error writing reg %#x: %d\n", reg, error); 99 } 100 101 #define I2C_READ(sc, reg) max77620_read((sc), (reg), 0) 102 #define I2C_WRITE(sc, reg, val) max77620_write((sc), (reg), (val), 0) 103 #define I2C_LOCK(sc) iic_acquire_bus((sc)->sc_i2c, 0) 104 #define I2C_UNLOCK(sc) iic_release_bus((sc)->sc_i2c, 0) 105 106 static int 107 max77620_gpio_config(struct max77620_softc *sc, int pin, int flags) 108 { 109 uint32_t gpio; 110 111 KASSERT(pin >= 0 && pin < MAX_GPIO_COUNT); 112 113 gpio = I2C_READ(sc, MAX_GPIO_REG(pin)); 114 115 switch (flags & (GPIO_PIN_INPUT|GPIO_PIN_OUTPUT)) { 116 case GPIO_PIN_INPUT: 117 gpio |= MAX_GPIO_DIR; 118 break; 119 case GPIO_PIN_OUTPUT: 120 gpio &= ~MAX_GPIO_DIR; 121 break; 122 default: 123 return EINVAL; 124 } 125 126 switch (flags & (GPIO_PIN_PUSHPULL|GPIO_PIN_OPENDRAIN)) { 127 case GPIO_PIN_PUSHPULL: 128 gpio |= MAX_GPIO_DRV; 129 break; 130 case GPIO_PIN_OPENDRAIN: 131 gpio &= ~MAX_GPIO_DRV; 132 break; 133 default: 134 return EINVAL; 135 } 136 137 I2C_WRITE(sc, MAX_GPIO_REG(pin), gpio); 138 139 return 0; 140 } 141 142 static void * 143 max77620_gpio_acquire(device_t dev, const void *data, size_t len, int flags) 144 { 145 struct max77620_softc * const sc = device_private(dev); 146 struct max77620_pin *gpin; 147 const u_int *gpio = data; 148 int error; 149 150 if (len != 12) 151 return NULL; 152 153 const uint8_t pin = be32toh(gpio[1]) & 0xff; 154 const bool actlo = (be32toh(gpio[2]) & __BIT(0)) != 0; 155 const bool pushpull = (be32toh(gpio[2]) & __BIT(1)) == 0; 156 const bool opendrain = (be32toh(gpio[2]) & __BIT(2)) != 0; 157 158 if (pushpull) 159 flags |= GPIO_PIN_PUSHPULL; 160 if (opendrain) 161 flags |= GPIO_PIN_OPENDRAIN; 162 163 if (pin >= MAX_GPIO_COUNT) 164 return NULL; 165 166 I2C_LOCK(sc); 167 error = max77620_gpio_config(sc, pin, flags); 168 I2C_UNLOCK(sc); 169 170 if (error != 0) { 171 device_printf(dev, "bad pin %d config %#x\n", pin, flags); 172 return NULL; 173 } 174 175 gpin = kmem_zalloc(sizeof(*gpin), KM_SLEEP); 176 gpin->pin_sc = sc; 177 gpin->pin_num = pin; 178 gpin->pin_flags = flags; 179 gpin->pin_actlo = actlo; 180 181 return gpin; 182 } 183 184 static void 185 max77620_gpio_release(device_t dev, void *priv) 186 { 187 struct max77620_softc * const sc = device_private(dev); 188 struct max77620_pin *gpin = priv; 189 190 I2C_LOCK(sc); 191 max77620_gpio_config(sc, gpin->pin_num, GPIO_PIN_INPUT|GPIO_PIN_OPENDRAIN); 192 I2C_UNLOCK(sc); 193 194 kmem_free(gpin, sizeof(*gpin)); 195 } 196 197 static int 198 max77620_gpio_read(device_t dev, void *priv, bool raw) 199 { 200 struct max77620_softc * const sc = device_private(dev); 201 struct max77620_pin *gpin = priv; 202 uint8_t gpio; 203 int val; 204 205 /* 206 * Performing a register read only; no need to acquire 207 * the max77620 lock. 208 */ 209 210 I2C_LOCK(sc); 211 gpio = I2C_READ(sc, MAX_GPIO_REG(gpin->pin_num)); 212 I2C_UNLOCK(sc); 213 214 val = __SHIFTOUT(gpio, MAX_GPIO_INPUT_VAL); 215 if (!raw && gpin->pin_actlo) 216 val = !val; 217 218 #ifdef MAX77620_DEBUG 219 device_printf(sc->sc_dev, "GPIO%d rd %02x (%d %d)\n", 220 gpin->pin_num, gpio, 221 (int)__SHIFTOUT(gpio, MAX_GPIO_INPUT_VAL), val); 222 #endif 223 224 return val; 225 } 226 227 static void 228 max77620_gpio_write(device_t dev, void *priv, int val, bool raw) 229 { 230 struct max77620_softc * const sc = device_private(dev); 231 struct max77620_pin *gpin = priv; 232 uint8_t gpio; 233 234 if (!raw && gpin->pin_actlo) 235 val = !val; 236 237 I2C_LOCK(sc); 238 gpio = I2C_READ(sc, MAX_GPIO_REG(gpin->pin_num)); 239 gpio &= ~MAX_GPIO_OUTPUT_VAL; 240 gpio |= __SHIFTIN(val, MAX_GPIO_OUTPUT_VAL); 241 #ifdef MAX77620_DEBUG 242 device_printf(sc->sc_dev, "GPIO%d wr %02x -> %02x\n", 243 gpin->pin_num, 244 I2C_READ(sc, MAX_GPIO_REG(gpin->pin_num)), gpio); 245 #endif 246 I2C_WRITE(sc, MAX_GPIO_REG(gpin->pin_num), gpio); 247 I2C_UNLOCK(sc); 248 } 249 250 static struct fdtbus_gpio_controller_func max77620_gpio_funcs = { 251 .acquire = max77620_gpio_acquire, 252 .release = max77620_gpio_release, 253 .read = max77620_gpio_read, 254 .write = max77620_gpio_write, 255 }; 256 257 static void 258 max77620_gpio_attach(struct max77620_softc *sc) 259 { 260 fdtbus_register_gpio_controller(sc->sc_dev, sc->sc_phandle, 261 &max77620_gpio_funcs); 262 } 263 264 static int 265 max77620_match(device_t parent, cfdata_t match, void *aux) 266 { 267 struct i2c_attach_args *ia = aux; 268 int match_result; 269 270 if (iic_use_direct_match(ia, match, compat_data, &match_result)) 271 return match_result; 272 273 return 0; 274 } 275 276 static void 277 max77620_attach(device_t parent, device_t self, void *aux) 278 { 279 struct max77620_softc * const sc = device_private(self); 280 struct i2c_attach_args *ia = aux; 281 282 sc->sc_dev = self; 283 sc->sc_i2c = ia->ia_tag; 284 sc->sc_addr = ia->ia_addr; 285 sc->sc_phandle = ia->ia_cookie; 286 287 aprint_naive("\n"); 288 aprint_normal(": MAX77620 Power Management IC\n"); 289 290 max77620_gpio_attach(sc); 291 } 292 293 CFATTACH_DECL_NEW(max77620pmic, sizeof(struct max77620_softc), 294 max77620_match, max77620_attach, NULL, NULL); 295
Indexes created Tue Sep 30 06:09:59 GMT 2025