/*- * SPDX-License-Identifier: BSD-2-Clause-FreeBSD * * Copyright (c) 2006 M. Warner Losh * * 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 AUTHOR ``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 AUTHOR 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 __FBSDID("$FreeBSD$"); /* * Generic IIC eeprom support, modeled after the AT24C family of products. */ #include "opt_platform.h" #include #include #include #include #include #include #include #include #include #include #include #ifdef FDT #include #include #endif #include #include #include "iicbus_if.h" /* * AT24 parts have a "write page size" that differs per-device, and a "read page * size" that is always equal to the full device size. We define maximum values * here to limit how long we occupy the bus with a single transfer, and because * there are temporary buffers of these sizes allocated on the stack. */ #define MAX_RD_SZ 256 /* Largest read size we support */ #define MAX_WR_SZ 256 /* Largest write size we support */ struct icee_softc { device_t dev; /* Myself */ struct cdev *cdev; /* user interface */ int addr; /* Slave address on the bus */ int size; /* How big am I? */ int type; /* What address type 8 or 16 bit? */ int wr_sz; /* What's the write page size */ }; #ifdef FDT struct eeprom_desc { int type; int size; int wr_sz; const char *name; }; static struct eeprom_desc type_desc[] = { { 8, 128, 8, "AT24C01"}, { 8, 256, 8, "AT24C02"}, { 8, 512, 16, "AT24C04"}, { 8, 1024, 16, "AT24C08"}, { 8, 2 * 1024, 16, "AT24C16"}, {16, 4 * 1024, 32, "AT24C32"}, {16, 8 * 1024, 32, "AT24C64"}, {16, 16 * 1024, 64, "AT24C128"}, {16, 32 * 1024, 64, "AT24C256"}, {16, 64 * 1024, 128, "AT24C512"}, {16, 128 * 1024, 256, "AT24CM01"}, }; static struct ofw_compat_data compat_data[] = { {"atmel,24c01", (uintptr_t)(&type_desc[0])}, {"atmel,24c02", (uintptr_t)(&type_desc[1])}, {"atmel,24c04", (uintptr_t)(&type_desc[2])}, {"atmel,24c08", (uintptr_t)(&type_desc[3])}, {"atmel,24c16", (uintptr_t)(&type_desc[4])}, {"atmel,24c32", (uintptr_t)(&type_desc[5])}, {"atmel,24c64", (uintptr_t)(&type_desc[6])}, {"atmel,24c128", (uintptr_t)(&type_desc[7])}, {"atmel,24c256", (uintptr_t)(&type_desc[8])}, {"atmel,24c512", (uintptr_t)(&type_desc[9])}, {"atmel,24c1024", (uintptr_t)(&type_desc[10])}, {NULL, (uintptr_t)NULL}, }; #endif #define CDEV2SOFTC(dev) ((dev)->si_drv1) /* cdev routines */ static d_read_t icee_read; static d_write_t icee_write; static struct cdevsw icee_cdevsw = { .d_version = D_VERSION, .d_read = icee_read, .d_write = icee_write }; static int icee_probe(device_t dev) { #ifdef FDT struct eeprom_desc *d; if (!ofw_bus_status_okay(dev)) return (ENXIO); d = (struct eeprom_desc *) ofw_bus_search_compatible(dev, compat_data)->ocd_data; if (d != NULL) { device_set_desc(dev, d->name); return (BUS_PROBE_DEFAULT); } #endif device_set_desc(dev, "I2C EEPROM"); return (BUS_PROBE_NOWILDCARD); } static int icee_init(struct icee_softc *sc) { const char *dname; int dunit; #ifdef FDT struct eeprom_desc *d; d = (struct eeprom_desc *) ofw_bus_search_compatible(sc->dev, compat_data)->ocd_data; if (d != NULL) { sc->size = d->size; sc->type = d->type; sc->wr_sz = d->wr_sz; return (0); } #endif dname = device_get_name(sc->dev); dunit = device_get_unit(sc->dev); if (resource_int_value(dname, dunit, "type", &sc->type) != 0) return (ENOENT); if (resource_int_value(dname, dunit, "size", &sc->size) != 0) return (ENOENT); if (resource_int_value(dname, dunit, "wr_sz", &sc->wr_sz) != 0) return (ENOENT); return (0); } static int icee_attach(device_t dev) { struct icee_softc *sc = device_get_softc(dev); struct sysctl_ctx_list *ctx; struct sysctl_oid_list *tree; sc->dev = dev; sc->addr = iicbus_get_addr(dev); if (icee_init(sc) != 0) return (EINVAL); if (bootverbose) device_printf(dev, "size: %d bytes, addressing: %d-bits\n", sc->size, sc->type); sc->cdev = make_dev(&icee_cdevsw, device_get_unit(dev), UID_ROOT, GID_WHEEL, 0600, "icee%d", device_get_unit(dev)); if (sc->cdev == NULL) { return (ENOMEM); } sc->cdev->si_drv1 = sc; ctx = device_get_sysctl_ctx(dev); tree = SYSCTL_CHILDREN(device_get_sysctl_tree(dev)); SYSCTL_ADD_INT(ctx, tree, OID_AUTO, "address_size", CTLFLAG_RD, &sc->type, 0, "Memory array address size in bits"); SYSCTL_ADD_INT(ctx, tree, OID_AUTO, "device_size", CTLFLAG_RD, &sc->size, 0, "Memory array capacity in bytes"); SYSCTL_ADD_INT(ctx, tree, OID_AUTO, "write_size", CTLFLAG_RD, &sc->wr_sz, 0, "Memory array page write size in bytes"); return (0); } static int icee_detach(device_t dev) { struct icee_softc *sc = device_get_softc(dev); destroy_dev(sc->cdev); return (0); } static int icee_read(struct cdev *dev, struct uio *uio, int ioflag) { struct icee_softc *sc; uint8_t addr[2]; uint8_t data[MAX_RD_SZ]; int error, i, len, slave; struct iic_msg msgs[2] = { { 0, IIC_M_WR, 1, addr }, { 0, IIC_M_RD, 0, data }, }; sc = CDEV2SOFTC(dev); if (uio->uio_offset == sc->size) return (0); if (uio->uio_offset > sc->size) return (EIO); if (sc->type != 8 && sc->type != 16) return (EINVAL); slave = error = 0; while (uio->uio_resid > 0) { if (uio->uio_offset >= sc->size) break; len = MIN(MAX_RD_SZ - (uio->uio_offset & (MAX_RD_SZ - 1)), uio->uio_resid); switch (sc->type) { case 8: slave = (uio->uio_offset >> 7) | sc->addr; msgs[0].len = 1; msgs[1].len = len; addr[0] = uio->uio_offset & 0xff; break; case 16: slave = sc->addr | (uio->uio_offset >> 15); msgs[0].len = 2; msgs[1].len = len; addr[0] = (uio->uio_offset >> 8) & 0xff; addr[1] = uio->uio_offset & 0xff; break; } for (i = 0; i < 2; i++) msgs[i].slave = slave; error = iicbus_transfer_excl(sc->dev, msgs, 2, IIC_INTRWAIT); if (error) { error = iic2errno(error); break; } error = uiomove(data, len, uio); if (error) break; } return (error); } /* * Write to the part. We use three transfers here since we're actually * doing a write followed by a read to make sure that the write finished. * It is easier to encode the dummy read here than to break things up * into smaller chunks... */ static int icee_write(struct cdev *dev, struct uio *uio, int ioflag) { struct icee_softc *sc; int error, len, slave, waitlimit; uint8_t data[MAX_WR_SZ + 2]; struct iic_msg wr[1] = { { 0, IIC_M_WR, 0, data }, }; struct iic_msg rd[1] = { { 0, IIC_M_RD, 1, data }, }; sc = CDEV2SOFTC(dev); if (uio->uio_offset >= sc->size) return (EIO); if (sc->type != 8 && sc->type != 16) return (EINVAL); slave = error = 0; while (uio->uio_resid > 0) { if (uio->uio_offset >= sc->size) break; len = MIN(sc->wr_sz - (uio->uio_offset & (sc->wr_sz - 1)), uio->uio_resid); switch (sc->type) { case 8: slave = (uio->uio_offset >> 7) | sc->addr; wr[0].len = 1 + len; data[0] = uio->uio_offset & 0xff; break; case 16: slave = sc->addr | (uio->uio_offset >> 15); wr[0].len = 2 + len; data[0] = (uio->uio_offset >> 8) & 0xff; data[1] = uio->uio_offset & 0xff; break; } wr[0].slave = slave; error = uiomove(data + sc->type / 8, len, uio); if (error) break; error = iicbus_transfer_excl(sc->dev, wr, 1, IIC_INTRWAIT); if (error) { error = iic2errno(error); break; } /* Read after write to wait for write-done. */ waitlimit = 10000; rd[0].slave = slave; do { error = iicbus_transfer_excl(sc->dev, rd, 1, IIC_INTRWAIT); } while (waitlimit-- > 0 && error != 0); if (error) { error = iic2errno(error); break; } } return error; } static device_method_t icee_methods[] = { DEVMETHOD(device_probe, icee_probe), DEVMETHOD(device_attach, icee_attach), DEVMETHOD(device_detach, icee_detach), DEVMETHOD_END }; static driver_t icee_driver = { "icee", icee_methods, sizeof(struct icee_softc), }; static devclass_t icee_devclass; DRIVER_MODULE(icee, iicbus, icee_driver, icee_devclass, 0, 0); MODULE_VERSION(icee, 1); MODULE_DEPEND(icee, iicbus, 1, 1, 1); IICBUS_FDT_PNP_INFO(compat_data);