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authorthorpej <thorpej@NetBSD.org>2020-12-23 04:09:32 +0000
committerthorpej <thorpej@NetBSD.org>2020-12-23 04:09:32 +0000
commit0b7cd3265056eec0a6ef1659baaaa2dc09d008e7 (patch)
tree36fbc0e705355ee6b49230bad49304712408c27c /sys
parentb27b9b1b8169bcac31da61b19cb3b5f81514aea6 (diff)
Add support for i2c-mux-gpio and i2c-mux-pinctrl I2C mux virtual
controllers.
Diffstat (limited to 'sys')
-rw-r--r--sys/arch/evbarm/conf/GENERIC5
-rw-r--r--sys/arch/evbarm/conf/GENERIC643
-rw-r--r--sys/dev/fdt/files.fdt6
-rw-r--r--sys/dev/fdt/i2cmux_fdt.c418
4 files changed, 428 insertions, 4 deletions
diff --git a/sys/arch/evbarm/conf/GENERIC b/sys/arch/evbarm/conf/GENERIC
index 7fcbe146677..a8cc8d14620 100644
--- a/sys/arch/evbarm/conf/GENERIC
+++ b/sys/arch/evbarm/conf/GENERIC
@@ -1,5 +1,5 @@
#
-# $NetBSD: GENERIC,v 1.83 2020/09/29 19:58:50 jmcneill Exp $
+# $NetBSD: GENERIC,v 1.84 2020/12/23 04:09:32 thorpej Exp $
#
# GENERIC ARM (aarch32) kernel
#
@@ -324,11 +324,12 @@ zynquart* at fdt? pass 4 # Cadence UART
options I2C_MAX_ADDR=0xfff
bsciic* at fdt? # Broadcom BCM283x Serial Control
exyoi2c* at fdt? # Samsung Exynos I2C
-imxi2c* at fdt? # i.MX I2C
+imxi2c* at fdt? pass 4 # i.MX I2C
sunxirsb* at fdt? pass 4 # Allwinner RSB
sunxitwi* at fdt? # Allwinner TWI
tegrai2c* at fdt? pass 4 # NVIDIA Tegra I2C
tiiic* at fdt? pass 4 # TI OMAP I2C
+iicmux* at fdt? pass 5 # I2C mux virtual controllers
iic* at i2cbus?
# I2C devices
diff --git a/sys/arch/evbarm/conf/GENERIC64 b/sys/arch/evbarm/conf/GENERIC64
index e8b98b7103c..8c328fc0a83 100644
--- a/sys/arch/evbarm/conf/GENERIC64
+++ b/sys/arch/evbarm/conf/GENERIC64
@@ -1,5 +1,5 @@
#
-# $NetBSD: GENERIC64,v 1.167 2020/12/13 20:40:38 jmcneill Exp $
+# $NetBSD: GENERIC64,v 1.168 2020/12/23 04:09:32 thorpej Exp $
#
# GENERIC ARM (aarch64) kernel
#
@@ -302,6 +302,7 @@ sunxitwi* at fdt? # Allwinner TWI
tegrai2c* at fdt? pass 4 # NVIDIA Tegra I2C
#sniiic* at fdt? # Socionext SC2A11 I2C
#sniiic* at acpi?
+iicmux* at fdt? pass 5 # I2C mux virtual controllers
iic* at i2cbus?
# I2C devices
diff --git a/sys/dev/fdt/files.fdt b/sys/dev/fdt/files.fdt
index b5e60dacd69..a9bd380ccd8 100644
--- a/sys/dev/fdt/files.fdt
+++ b/sys/dev/fdt/files.fdt
@@ -1,4 +1,4 @@
-# $NetBSD: files.fdt,v 1.57 2020/12/12 09:27:31 skrll Exp $
+# $NetBSD: files.fdt,v 1.58 2020/12/23 04:09:32 thorpej Exp $
include "external/bsd/libfdt/conf/files.libfdt"
@@ -54,6 +54,10 @@ device dispcon: fdt_port, drmkms, ddc_read_edid
attach dispcon at fdt with dispcon_hdmi
file dev/fdt/hdmi_connector.c dispcon_hdmi
+device iicmux: i2cbus
+attach iicmux at fdt with iicmux_fdt
+file dev/fdt/i2cmux_fdt.c iicmux_fdt
+
file dev/fdt/fdt_memory.c fdtbase
file dev/fdt/fdt_openfirm.c fdtbase
file dev/fdt/fdt_subr.c fdtbase
diff --git a/sys/dev/fdt/i2cmux_fdt.c b/sys/dev/fdt/i2cmux_fdt.c
new file mode 100644
index 00000000000..be3f80548db
--- /dev/null
+++ b/sys/dev/fdt/i2cmux_fdt.c
@@ -0,0 +1,418 @@
+/* $NetBSD: i2cmux_fdt.c,v 1.1 2020/12/23 04:09:32 thorpej Exp $ */
+
+/*-
+ * Copyright (c) 2020 The NetBSD Foundation, Inc.
+ * All rights reserved.
+ *
+ * This code is derived from software contributed to The NetBSD Foundation
+ * by Jason R. Thorpe.
+ *
+ * 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 <sys/cdefs.h>
+__KERNEL_RCSID(0, "$NetBSD: i2cmux_fdt.c,v 1.1 2020/12/23 04:09:32 thorpej Exp $");
+
+#include <sys/types.h>
+#include <sys/device.h>
+#include <sys/kernel.h>
+#include <sys/kmem.h>
+#include <sys/bus.h>
+#include <sys/gpio.h>
+
+#include <dev/fdt/fdtvar.h>
+#include <dev/i2c/i2cvar.h>
+
+/*
+ * i2c mux
+ *
+ * This works by interposing a virtual controller in front of the
+ * real i2c controller. We provide our own acquire release functions
+ * that perform the following tasks:
+ *
+ * acquire -> acquire parent controller, program mux
+ *
+ * release -> idle mux, release parent controller
+ *
+ * All of the actual I/O operations are transparently passed through.
+ *
+ * N.B. the locking order; the generic I2C layer has already acquired
+ * our virtual controller's mutex before calling our acquire function,
+ * and we will then acquire the real controller's mutex when we acquire
+ * the bus, so the order is:
+ *
+ * mux virtual controller -> parent controller
+ */
+
+struct iicmux_softc;
+struct iicmux_bus;
+
+struct iicmux_config {
+ const char *desc;
+ int (*get_mux_info)(struct iicmux_softc *);
+ int (*get_bus_info)(struct iicmux_bus *);
+ int (*acquire_bus)(struct iicmux_bus *, int);
+ void (*release_bus)(struct iicmux_bus *, int);
+};
+
+struct iicmux_bus {
+ struct i2c_controller controller;
+ struct iicmux_softc *mux;
+ int phandle;
+ int busidx;
+
+ union {
+ struct {
+ bus_addr_t value;
+ } gpio;
+
+ struct {
+ bus_addr_t idx;
+ } pinctrl;
+ };
+};
+
+struct iicmux_softc {
+ device_t sc_dev;
+ int sc_phandle;
+ const struct iicmux_config * sc_config;
+ i2c_tag_t sc_i2c_parent;
+ struct iicmux_bus * sc_busses;
+ int sc_nbusses;
+
+ union {
+ struct {
+ struct fdtbus_gpio_pin **pins;
+ int npins;
+ uint32_t idle_value;
+ bool has_idle_value;
+ } sc_gpio;
+
+ struct {
+ u_int idle_idx;
+ bool has_idle_idx;
+ } sc_pinctrl;
+ };
+};
+
+/*****************************************************************************/
+
+static int
+iicmux_acquire_bus(void * const v, int const flags)
+{
+ struct iicmux_bus * const bus = v;
+ struct iicmux_softc * const sc = bus->mux;
+ int error;
+
+ error = iic_acquire_bus(sc->sc_i2c_parent, flags);
+ if (error) {
+ return error;
+ }
+
+ error = sc->sc_config->acquire_bus(bus, flags);
+ if (error) {
+ iic_release_bus(sc->sc_i2c_parent, flags);
+ }
+
+ return error;
+}
+
+static void
+iicmux_release_bus(void * const v, int const flags)
+{
+ struct iicmux_bus * const bus = v;
+ struct iicmux_softc * const sc = bus->mux;
+
+ sc->sc_config->release_bus(bus, flags);
+ iic_release_bus(sc->sc_i2c_parent, flags);
+}
+
+static int
+iicmux_exec(void * const v, i2c_op_t const op, i2c_addr_t const addr,
+ const void * const cmdbuf, size_t const cmdlen, void * const databuf,
+ size_t const datalen, int const flags)
+{
+ struct iicmux_bus * const bus = v;
+ struct iicmux_softc * const sc = bus->mux;
+
+ return iic_exec(sc->sc_i2c_parent, op, addr, cmdbuf, cmdlen,
+ databuf, datalen, flags);
+}
+
+/*****************************************************************************/
+
+static int
+iicmux_gpio_get_mux_info(struct iicmux_softc * const sc)
+{
+ int i;
+
+ sc->sc_gpio.npins = fdtbus_gpio_count(sc->sc_phandle, "mux-gpios");
+ if (sc->sc_gpio.npins == 0) {
+ aprint_error_dev(sc->sc_dev,
+ "unable to get mux-gpios property\n");
+ return ENXIO;
+ }
+
+ sc->sc_gpio.pins =
+ kmem_zalloc(sizeof(*sc->sc_gpio.pins) * sc->sc_gpio.npins,
+ KM_SLEEP);
+ for (i = 0; i < sc->sc_gpio.npins; i++) {
+ sc->sc_gpio.pins[i] = fdtbus_gpio_acquire_index(sc->sc_phandle,
+ "mux-gpios", i, GPIO_PIN_OUTPUT);
+ if (sc->sc_gpio.pins[i] == NULL) {
+ aprint_error_dev(sc->sc_dev,
+ "unable to acquire gpio #%d\n", i);
+ return ENXIO;
+ }
+ }
+
+ sc->sc_gpio.has_idle_value =
+ of_getprop_uint32(sc->sc_phandle, "idle-state",
+ &sc->sc_gpio.idle_value) == 0;
+
+ return 0;
+}
+
+static int
+iicmux_gpio_get_bus_info(struct iicmux_bus * const bus)
+{
+ struct iicmux_softc * const sc = bus->mux;
+ int error;
+
+ error = fdtbus_get_reg(bus->phandle, 0, &bus->gpio.value, NULL);
+ if (error) {
+ aprint_error_dev(sc->sc_dev,
+ "unable to get reg property for bus %d\n", bus->busidx);
+ }
+
+ return error;
+}
+
+static void
+iicmux_gpio_set_value(struct iicmux_softc * const sc, bus_addr_t value)
+{
+ int i;
+
+ for (i = 0; i < sc->sc_gpio.npins; i++, value >>= 1) {
+ fdtbus_gpio_write(sc->sc_gpio.pins[i], value & 1);
+ }
+}
+
+static int
+iicmux_gpio_acquire_bus(struct iicmux_bus * const bus, int const flags __unused)
+{
+ iicmux_gpio_set_value(bus->mux, bus->gpio.value);
+
+ return 0;
+}
+
+static void
+iicmux_gpio_release_bus(struct iicmux_bus * const bus, int const flags __unused)
+{
+ struct iicmux_softc *sc = bus->mux;
+
+ if (sc->sc_gpio.has_idle_value) {
+ iicmux_gpio_set_value(sc, sc->sc_gpio.idle_value);
+ }
+}
+
+static const struct iicmux_config iicmux_gpio_config = {
+ .desc = "GPIO",
+ .get_mux_info = iicmux_gpio_get_mux_info,
+ .get_bus_info = iicmux_gpio_get_bus_info,
+ .acquire_bus = iicmux_gpio_acquire_bus,
+ .release_bus = iicmux_gpio_release_bus,
+};
+
+/*****************************************************************************/
+
+static int
+iicmux_pinctrl_get_mux_info(struct iicmux_softc * const sc)
+{
+
+ sc->sc_pinctrl.has_idle_idx =
+ fdtbus_get_index(sc->sc_phandle, "pinctrl-names", "idle",
+ &sc->sc_pinctrl.idle_idx) == 0;
+
+ return 0;
+}
+
+static int
+iicmux_pinctrl_get_bus_info(struct iicmux_bus * const bus)
+{
+ struct iicmux_softc * const sc = bus->mux;
+ int error;
+
+ error = fdtbus_get_reg(bus->phandle, 0, &bus->pinctrl.idx,
+ NULL);
+ if (error) {
+ aprint_error_dev(sc->sc_dev,
+ "unable to get reg property for bus %d\n", bus->busidx);
+ }
+
+ return error;
+}
+
+static int
+iicmux_pinctrl_acquire_bus(struct iicmux_bus * const bus,
+ int const flags __unused)
+{
+ struct iicmux_softc * const sc = bus->mux;
+
+ return fdtbus_pinctrl_set_config_index(sc->sc_phandle,
+ bus->pinctrl.idx);
+}
+
+static void
+iicmux_pinctrl_release_bus(struct iicmux_bus * const bus,
+ int const flags __unused)
+{
+ struct iicmux_softc * const sc = bus->mux;
+
+ if (sc->sc_pinctrl.has_idle_idx) {
+ (void) fdtbus_pinctrl_set_config_index(sc->sc_phandle,
+ sc->sc_pinctrl.idle_idx);
+ }
+}
+
+static const struct iicmux_config iicmux_pinctrl_config = {
+ .desc = "PinMux",
+ .get_mux_info = iicmux_pinctrl_get_mux_info,
+ .get_bus_info = iicmux_pinctrl_get_bus_info,
+ .acquire_bus = iicmux_pinctrl_acquire_bus,
+ .release_bus = iicmux_pinctrl_release_bus,
+};
+
+/*****************************************************************************/
+
+static const struct of_compat_data compat_data[] = {
+ { .compat = "i2c-mux-gpio",
+ .data = (uintptr_t)&iicmux_gpio_config },
+
+ { .compat = "i2c-mux-pinctrl",
+ .data = (uintptr_t)&iicmux_pinctrl_config },
+
+ { NULL }
+};
+
+static int
+iicmux_count_children(struct iicmux_softc * const sc)
+{
+ int child, count;
+
+ for (child = OF_child(sc->sc_phandle), count = 0; child;
+ child = OF_peer(child)) {
+ count++;
+ }
+
+ return count;
+}
+
+/* XXX iicbus_print() should be able to do this. */
+static int
+iicmux_print(void * const aux, const char * const pnp)
+{
+ i2c_tag_t const tag = aux;
+ struct iicmux_bus * const bus = tag->ic_cookie;
+ int rv;
+
+ rv = iicbus_print(aux, pnp);
+ aprint_normal(" bus %d", bus->busidx);
+
+ return rv;
+}
+
+static void
+iicmux_attach_bus(struct iicmux_softc * const sc,
+ int const phandle, int const busidx)
+{
+ struct iicmux_bus * const bus = &sc->sc_busses[busidx];
+ int error;
+
+ bus->mux = sc;
+ bus->busidx = busidx;
+ bus->phandle = phandle;
+
+ error = sc->sc_config->get_bus_info(bus);
+ if (error) {
+ aprint_error_dev(sc->sc_dev,
+ "unable to get info for bus %d, error %d\n",
+ busidx, error);
+ return;
+ }
+
+ iic_tag_init(&bus->controller);
+ bus->controller.ic_cookie = bus;
+ bus->controller.ic_acquire_bus = iicmux_acquire_bus;
+ bus->controller.ic_release_bus = iicmux_release_bus;
+ bus->controller.ic_exec = iicmux_exec;
+
+ fdtbus_attach_i2cbus(sc->sc_dev, bus->phandle, &bus->controller,
+ iicmux_print);
+}
+
+static int
+iicmux_fdt_match(device_t const parent, cfdata_t const match, void * const aux)
+{
+ struct fdt_attach_args * const faa = aux;
+
+ return of_match_compat_data(faa->faa_phandle, compat_data);
+}
+
+static void
+iicmux_fdt_attach(device_t const parent, device_t const self, void * const aux)
+{
+ struct iicmux_softc * const sc = device_private(self);
+ struct fdt_attach_args * const faa = aux;
+
+ sc->sc_dev = self;
+ sc->sc_phandle = faa->faa_phandle;
+ sc->sc_config = (const struct iicmux_config *)
+ of_search_compatible(sc->sc_phandle, compat_data)->data;
+
+ aprint_naive("\n");
+ aprint_normal(": %s I2C mux\n", sc->sc_config->desc);
+
+ sc->sc_i2c_parent = fdtbus_i2c_acquire(sc->sc_phandle, "i2c-parent");
+ if (sc->sc_i2c_parent == NULL) {
+ aprint_error_dev(sc->sc_dev, "unable to acquire i2c-parent\n");
+ return;
+ }
+
+ const int nchildren = iicmux_count_children(sc);
+ if (nchildren == 0) {
+ return;
+ }
+
+ sc->sc_busses = kmem_zalloc(sizeof(*sc->sc_busses) * nchildren,
+ KM_SLEEP);
+
+ int child, idx;
+ for (child = OF_child(sc->sc_phandle), idx = 0; child;
+ child = OF_peer(child), idx++) {
+ KASSERT(idx < nchildren);
+ iicmux_attach_bus(sc, child, idx);
+ }
+}
+
+CFATTACH_DECL_NEW(iicmux_fdt, sizeof(struct iicmux_softc),
+ iicmux_fdt_match, iicmux_fdt_attach, NULL, NULL);