1 /* $NetBSD: max77620.c,v 1.11 2021/01/27 02:29:48 thorpej Exp $ */ 2 3 /*- 4 * Copyright (c) 2017 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: max77620.c,v 1.11 2021/01/27 02:29:48 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 DEVICE_COMPAT_EOL 73 }; 74 75 static uint8_t 76 max77620_read(struct max77620_softc *sc, uint8_t reg, int flags) 77 { 78 uint8_t val = 0; 79 int error; 80 81 error = iic_exec(sc->sc_i2c, I2C_OP_READ_WITH_STOP, sc->sc_addr, 82 ®, 1, &val, 1, flags); 83 if (error != 0) 84 aprint_error_dev(sc->sc_dev, "error reading reg %#x: %d\n", reg, error); 85 86 return val; 87 } 88 89 static void 90 max77620_write(struct max77620_softc *sc, uint8_t reg, uint8_t val, int flags) 91 { 92 int error; 93 94 error = iic_exec(sc->sc_i2c, I2C_OP_WRITE_WITH_STOP, sc->sc_addr, 95 ®, 1, &val, 1, flags); 96 if (error != 0) 97 aprint_error_dev(sc->sc_dev, "error writing reg %#x: %d\n", reg, error); 98 } 99 100 #define I2C_READ(sc, reg) max77620_read((sc), (reg), 0) 101 #define I2C_WRITE(sc, reg, val) max77620_write((sc), (reg), (val), 0) 102 #define I2C_LOCK(sc) iic_acquire_bus((sc)->sc_i2c, 0) 103 #define I2C_UNLOCK(sc) iic_release_bus((sc)->sc_i2c, 0) 104 105 static int 106 max77620_gpio_config(struct max77620_softc *sc, int pin, int flags) 107 { 108 uint32_t gpio; 109 110 KASSERT(pin >= 0 && pin < MAX_GPIO_COUNT); 111 112 gpio = I2C_READ(sc, MAX_GPIO_REG(pin)); 113 114 switch (flags & (GPIO_PIN_INPUT|GPIO_PIN_OUTPUT)) { 115 case GPIO_PIN_INPUT: 116 gpio |= MAX_GPIO_DIR; 117 break; 118 case GPIO_PIN_OUTPUT: 119 gpio &= ~MAX_GPIO_DIR; 120 break; 121 default: 122 return EINVAL; 123 } 124 125 switch (flags & (GPIO_PIN_PUSHPULL|GPIO_PIN_OPENDRAIN)) { 126 case GPIO_PIN_PUSHPULL: 127 gpio |= MAX_GPIO_DRV; 128 break; 129 case GPIO_PIN_OPENDRAIN: 130 gpio &= ~MAX_GPIO_DRV; 131 break; 132 default: 133 return EINVAL; 134 } 135 136 I2C_WRITE(sc, MAX_GPIO_REG(pin), gpio); 137 138 return 0; 139 } 140 141 static void * 142 max77620_gpio_acquire(device_t dev, const void *data, size_t len, int flags) 143 { 144 struct max77620_softc * const sc = device_private(dev); 145 struct max77620_pin *gpin; 146 const u_int *gpio = data; 147 int error; 148 149 if (len != 12) 150 return NULL; 151 152 const uint8_t pin = be32toh(gpio[1]) & 0xff; 153 const bool actlo = (be32toh(gpio[2]) & __BIT(0)) != 0; 154 const bool pushpull = (be32toh(gpio[2]) & __BIT(1)) == 0; 155 const bool opendrain = (be32toh(gpio[2]) & __BIT(2)) != 0; 156 157 if (pushpull) 158 flags |= GPIO_PIN_PUSHPULL; 159 if (opendrain) 160 flags |= GPIO_PIN_OPENDRAIN; 161 162 if (pin >= MAX_GPIO_COUNT) 163 return NULL; 164 165 I2C_LOCK(sc); 166 error = max77620_gpio_config(sc, pin, flags); 167 I2C_UNLOCK(sc); 168 169 if (error != 0) { 170 device_printf(dev, "bad pin %d config %#x\n", pin, flags); 171 return NULL; 172 } 173 174 gpin = kmem_zalloc(sizeof(*gpin), KM_SLEEP); 175 gpin->pin_sc = sc; 176 gpin->pin_num = pin; 177 gpin->pin_flags = flags; 178 gpin->pin_actlo = actlo; 179 180 return gpin; 181 } 182 183 static void 184 max77620_gpio_release(device_t dev, void *priv) 185 { 186 struct max77620_softc * const sc = device_private(dev); 187 struct max77620_pin *gpin = priv; 188 189 I2C_LOCK(sc); 190 max77620_gpio_config(sc, gpin->pin_num, GPIO_PIN_INPUT|GPIO_PIN_OPENDRAIN); 191 I2C_UNLOCK(sc); 192 193 kmem_free(gpin, sizeof(*gpin)); 194 } 195 196 static int 197 max77620_gpio_read(device_t dev, void *priv, bool raw) 198 { 199 struct max77620_softc * const sc = device_private(dev); 200 struct max77620_pin *gpin = priv; 201 uint8_t gpio; 202 int val; 203 204 /* 205 * Performing a register read only; no need to acquire 206 * the max77620 lock. 207 */ 208 209 I2C_LOCK(sc); 210 gpio = I2C_READ(sc, MAX_GPIO_REG(gpin->pin_num)); 211 I2C_UNLOCK(sc); 212 213 val = __SHIFTOUT(gpio, MAX_GPIO_INPUT_VAL); 214 if (!raw && gpin->pin_actlo) 215 val = !val; 216 217 #ifdef MAX77620_DEBUG 218 device_printf(sc->sc_dev, "GPIO%d rd %02x (%d %d)\n", 219 gpin->pin_num, gpio, 220 (int)__SHIFTOUT(gpio, MAX_GPIO_INPUT_VAL), val); 221 #endif 222 223 return val; 224 } 225 226 static void 227 max77620_gpio_write(device_t dev, void *priv, int val, bool raw) 228 { 229 struct max77620_softc * const sc = device_private(dev); 230 struct max77620_pin *gpin = priv; 231 uint8_t gpio; 232 233 if (!raw && gpin->pin_actlo) 234 val = !val; 235 236 I2C_LOCK(sc); 237 gpio = I2C_READ(sc, MAX_GPIO_REG(gpin->pin_num)); 238 gpio &= ~MAX_GPIO_OUTPUT_VAL; 239 gpio |= __SHIFTIN(val, MAX_GPIO_OUTPUT_VAL); 240 #ifdef MAX77620_DEBUG 241 device_printf(sc->sc_dev, "GPIO%d wr %02x -> %02x\n", 242 gpin->pin_num, 243 I2C_READ(sc, MAX_GPIO_REG(gpin->pin_num)), gpio); 244 #endif 245 I2C_WRITE(sc, MAX_GPIO_REG(gpin->pin_num), gpio); 246 I2C_UNLOCK(sc); 247 } 248 249 static struct fdtbus_gpio_controller_func max77620_gpio_funcs = { 250 .acquire = max77620_gpio_acquire, 251 .release = max77620_gpio_release, 252 .read = max77620_gpio_read, 253 .write = max77620_gpio_write, 254 }; 255 256 static void 257 max77620_gpio_attach(struct max77620_softc *sc) 258 { 259 fdtbus_register_gpio_controller(sc->sc_dev, sc->sc_phandle, 260 &max77620_gpio_funcs); 261 } 262 263 static int 264 max77620_match(device_t parent, cfdata_t match, void *aux) 265 { 266 struct i2c_attach_args *ia = aux; 267 int match_result; 268 269 if (iic_use_direct_match(ia, match, compat_data, &match_result)) 270 return match_result; 271 272 return 0; 273 } 274 275 static void 276 max77620_attach(device_t parent, device_t self, void *aux) 277 { 278 struct max77620_softc * const sc = device_private(self); 279 struct i2c_attach_args *ia = aux; 280 281 sc->sc_dev = self; 282 sc->sc_i2c = ia->ia_tag; 283 sc->sc_addr = ia->ia_addr; 284 sc->sc_phandle = ia->ia_cookie; 285 286 aprint_naive("\n"); 287 aprint_normal(": MAX77620 Power Management IC\n"); 288 289 max77620_gpio_attach(sc); 290 } 291 292 CFATTACH_DECL_NEW(max77620pmic, sizeof(struct max77620_softc), 293 max77620_match, max77620_attach, NULL, NULL); 294