/* $NetBSD: tcagpio.c,v 1.8 2021/01/27 02:29:48 thorpej Exp $ */ /*- * Copyright (c) 2017 Jared McNeill * 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 NETBSD FOUNDATION, INC. 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 FOUNDATION 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. */ #include __KERNEL_RCSID(0, "$NetBSD: tcagpio.c,v 1.8 2021/01/27 02:29:48 thorpej Exp $"); #include #include #include #include #include #include #include #include #include #include #define PORT_BANK(pin) (pin / 8) #define PORT_BIT(pin) __BIT(pin % 8) #define PORT_IN(pin) (0x00 + PORT_BANK(pin)) #define PORT_OUT(pin) (0x02 + PORT_BANK(pin)) #define PORT_POLARITY(pin) (0x04 + PORT_BANK(pin)) #define PORT_CFG(pin) (0x06 + PORT_BANK(pin)) #define TCA_PIN_COUNT 16 struct tcagpio_softc { device_t sc_dev; i2c_tag_t sc_i2c; i2c_addr_t sc_addr; int sc_phandle; int sc_npins; }; struct tcagpio_pin { struct tcagpio_softc *pin_sc; int pin_num; int pin_flags; bool pin_actlo; }; static const struct device_compatible_entry compat_data[] = { { .compat = "ti,tca9539" }, DEVICE_COMPAT_EOL }; static uint8_t tcagpio_read(struct tcagpio_softc *sc, uint8_t reg, int flags) { uint8_t val = 0; int error; error = iic_exec(sc->sc_i2c, I2C_OP_READ_WITH_STOP, sc->sc_addr, ®, 1, &val, 1, flags); if (error != 0) aprint_error_dev(sc->sc_dev, "error reading reg %#x: %d\n", reg, error); return val; } static void tcagpio_write(struct tcagpio_softc *sc, uint8_t reg, uint8_t val, int flags) { uint8_t buf[2]; int error; buf[0] = reg; buf[1] = val; error = iic_exec(sc->sc_i2c, I2C_OP_WRITE_WITH_STOP, sc->sc_addr, NULL, 0, buf, 2, flags); if (error != 0) aprint_error_dev(sc->sc_dev, "error writing reg %#x: %d\n", reg, error); } #define I2C_READ(sc, reg) tcagpio_read((sc), (reg), 0) #define I2C_WRITE(sc, reg, val) tcagpio_write((sc), (reg), (val), 0) #define I2C_LOCK(sc) iic_acquire_bus((sc)->sc_i2c, 0) #define I2C_UNLOCK(sc) iic_release_bus((sc)->sc_i2c, 0) static int tcagpio_gpio_config(struct tcagpio_softc *sc, int pin, int flags) { uint16_t gpio; KASSERT(pin >= 0 && pin < sc->sc_npins); gpio = I2C_READ(sc, PORT_CFG(pin)); switch (flags & (GPIO_PIN_INPUT|GPIO_PIN_OUTPUT)) { case GPIO_PIN_INPUT: gpio |= PORT_BIT(pin); break; case GPIO_PIN_OUTPUT: gpio &= ~PORT_BIT(pin); break; default: return EINVAL; } I2C_WRITE(sc, PORT_CFG(pin), gpio); return 0; } static void * tcagpio_gpio_acquire(device_t dev, const void *data, size_t len, int flags) { struct tcagpio_softc * const sc = device_private(dev); struct tcagpio_pin *gpin; const u_int *gpio = data; int error; if (len != 12) return NULL; const uint8_t pin = be32toh(gpio[1]) & 0xff; const bool actlo = (be32toh(gpio[2]) & __BIT(0)) != 0; if (pin >= sc->sc_npins) return NULL; I2C_LOCK(sc); error = tcagpio_gpio_config(sc, pin, flags); I2C_UNLOCK(sc); if (error != 0) { device_printf(dev, "bad pin %d config %#x\n", pin, flags); return NULL; } gpin = kmem_zalloc(sizeof(*gpin), KM_SLEEP); gpin->pin_sc = sc; gpin->pin_num = pin; gpin->pin_flags = flags; gpin->pin_actlo = actlo; return gpin; } static void tcagpio_gpio_release(device_t dev, void *priv) { struct tcagpio_softc * const sc = device_private(dev); struct tcagpio_pin *gpin = priv; I2C_LOCK(sc); tcagpio_gpio_config(sc, gpin->pin_num, GPIO_PIN_INPUT); I2C_UNLOCK(sc); kmem_free(gpin, sizeof(*gpin)); } static int tcagpio_gpio_read(device_t dev, void *priv, bool raw) { struct tcagpio_softc * const sc = device_private(dev); struct tcagpio_pin *gpin = priv; uint8_t gpio; int val; I2C_LOCK(sc); gpio = I2C_READ(sc, PORT_IN(gpin->pin_num)); I2C_UNLOCK(sc); val = __SHIFTOUT(gpio, PORT_BIT(gpin->pin_num)); if (!raw && gpin->pin_actlo) val = !val; #ifdef TCAGPIO_DEBUG device_printf(sc->sc_dev, "GPIO%d rd %02x (%d %d)\n", gpin->pin_num, gpio, (int)__SHIFTOUT(gpio, PORT_BIT(gpin->pin_num)), val); #endif return val; } static void tcagpio_gpio_write(device_t dev, void *priv, int val, bool raw) { struct tcagpio_softc * const sc = device_private(dev); struct tcagpio_pin *gpin = priv; uint8_t gpio; if (!raw && gpin->pin_actlo) val = !val; I2C_LOCK(sc); gpio = I2C_READ(sc, PORT_OUT(gpin->pin_num)); gpio &= ~PORT_BIT(gpin->pin_num); gpio |= __SHIFTIN(val, PORT_BIT(gpin->pin_num)); #ifdef TCAGPIO_DEBUG device_printf(sc->sc_dev, "GPIO%d wr %02x -> %02x\n", gpin->pin_num, I2C_READ(sc, PORT_OUT(gpin->pin_num)), gpio); #endif I2C_WRITE(sc, PORT_OUT(gpin->pin_num), gpio); I2C_UNLOCK(sc); } static struct fdtbus_gpio_controller_func tcagpio_gpio_funcs = { .acquire = tcagpio_gpio_acquire, .release = tcagpio_gpio_release, .read = tcagpio_gpio_read, .write = tcagpio_gpio_write, }; static void tcagpio_gpio_attach(struct tcagpio_softc *sc) { fdtbus_register_gpio_controller(sc->sc_dev, sc->sc_phandle, &tcagpio_gpio_funcs); } static int tcagpio_match(device_t parent, cfdata_t match, void *aux) { struct i2c_attach_args *ia = aux; int match_result; if (iic_use_direct_match(ia, match, compat_data, &match_result)) return match_result; return 0; } static void tcagpio_attach(device_t parent, device_t self, void *aux) { struct tcagpio_softc * const sc = device_private(self); struct i2c_attach_args *ia = aux; sc->sc_dev = self; sc->sc_i2c = ia->ia_tag; sc->sc_addr = ia->ia_addr; sc->sc_phandle = ia->ia_cookie; sc->sc_npins = TCA_PIN_COUNT; aprint_naive("\n"); aprint_normal(": I2C/SMBus I/O Expander\n"); tcagpio_gpio_attach(sc); } CFATTACH_DECL_NEW(tcagpio, sizeof(struct tcagpio_softc), tcagpio_match, tcagpio_attach, NULL, NULL);