| Message ID | 20191002124749.7503-2-jjhiblot@ti.com |
|---|---|
| State | Changes Requested |
| Delegated to: | Tom Rini |
| Headers | show |
| Series | drivers: Add a framework for MUX drivers | expand |
Hi Jean-Jacques, On Wed, 2 Oct 2019 at 06:47, Jean-Jacques Hiblot <jjhiblot@ti.com> wrote: > > Add a new subsystem that handles multiplexer controllers. The API is the > same as in Linux. > > Signed-off-by: Jean-Jacques Hiblot <jjhiblot@ti.com> > --- > > drivers/Kconfig | 2 + > drivers/Makefile | 1 + > drivers/mux/Kconfig | 7 + > drivers/mux/Makefile | 6 + > drivers/mux/mux-uclass.c | 296 ++++++++++++++++++++++++++++++++++ > include/dm/uclass-id.h | 1 + > include/dt-bindings/mux/mux.h | 17 ++ > include/mux-internal.h | 80 +++++++++ > include/mux.h | 114 +++++++++++++ > 9 files changed, 524 insertions(+) > create mode 100644 drivers/mux/Kconfig > create mode 100644 drivers/mux/Makefile > create mode 100644 drivers/mux/mux-uclass.c > create mode 100644 include/dt-bindings/mux/mux.h > create mode 100644 include/mux-internal.h > create mode 100644 include/mux.h > I feel this needs more documentation. What is a multiplexer? > diff --git a/drivers/Kconfig b/drivers/Kconfig > index 350acf81f3..5334974ad4 100644 > --- a/drivers/Kconfig > +++ b/drivers/Kconfig > @@ -60,6 +60,8 @@ source "drivers/mmc/Kconfig" > > source "drivers/mtd/Kconfig" > > +source "drivers/mux/Kconfig" > + > source "drivers/net/Kconfig" > > source "drivers/nvme/Kconfig" > diff --git a/drivers/Makefile b/drivers/Makefile > index a4bb5e4975..f4d71f3b3c 100644 > --- a/drivers/Makefile > +++ b/drivers/Makefile > @@ -12,6 +12,7 @@ obj-$(CONFIG_$(SPL_TPL_)INPUT) += input/ > obj-$(CONFIG_$(SPL_TPL_)LED) += led/ > obj-$(CONFIG_$(SPL_TPL_)MMC_SUPPORT) += mmc/ > obj-$(CONFIG_$(SPL_TPL_)NAND_SUPPORT) += mtd/nand/raw/ > +obj-$(CONFIG_$(SPl_)MULTIPLEXER) += mux/ SPL? > obj-$(CONFIG_$(SPL_TPL_)PCH_SUPPORT) += pch/ > obj-$(CONFIG_$(SPL_TPL_)PCI) += pci/ > obj-$(CONFIG_$(SPL_TPL_)PHY) += phy/ > diff --git a/drivers/mux/Kconfig b/drivers/mux/Kconfig > new file mode 100644 > index 0000000000..ad0199c058 > --- /dev/null > +++ b/drivers/mux/Kconfig > @@ -0,0 +1,7 @@ > +menu "Multiplexer drivers" > + > +config MULTIPLEXER > + bool "Multiplexer Support" > + depends on DM > + > +endmenu > diff --git a/drivers/mux/Makefile b/drivers/mux/Makefile > new file mode 100644 > index 0000000000..351e4363d3 > --- /dev/null > +++ b/drivers/mux/Makefile > @@ -0,0 +1,6 @@ > +# SPDX-License-Identifier: GPL-2.0+ > +# > +# (C) Copyright 2019 > +# Jean-Jacques Hiblot <jjhiblot@ti.com> > + > +obj-$(CONFIG_$(SPL_)MULTIPLEXER) += mux-uclass.o > diff --git a/drivers/mux/mux-uclass.c b/drivers/mux/mux-uclass.c > new file mode 100644 > index 0000000000..58998af29c > --- /dev/null > +++ b/drivers/mux/mux-uclass.c > @@ -0,0 +1,296 @@ > +// SPDX-License-Identifier: GPL-2.0 > +/* > + * Multiplexer subsystem > + * > + * Based on the linux multiplexer framework > + * > + * Copyright (C) 2017 Axentia Technologies AB > + * Author: Peter Rosin <peda@axentia.se> > + * > + * Copyright (C) 2017-2018 Texas Instruments Incorporated - http://www.ti.com/ > + * Jean-Jacques Hiblot <jjhiblot@ti.com> > + */ > + > +#include <common.h> > +#include <mux-internal.h> should go above the dm/device-internal > +#include <dm.h> > +#include <dt-structs.h> Shouldn't need this > +#include <errno.h> Shouldn't need this > +#include <dm/device-internal.h> > +#include <dm/lists.h> > +#include <dm/read.h> Shouldn't need this > +#include <dt-bindings/mux/mux.h> > + > +/* > + * The idle-as-is "state" is not an actual state that may be selected, it > + * only implies that the state should not be changed. So, use that state > + * as indication that the cached state of the multiplexer is unknown. > + */ > +#define MUX_CACHE_UNKNOWN MUX_IDLE_AS_IS > + > +static inline const struct mux_control_ops *mux_dev_ops(struct udevice *dev) > +{ > + return (const struct mux_control_ops *)dev->driver->ops; > +} > + > +static int mux_control_set(struct mux_control *mux, int state) > +{ > + int ret = mux_dev_ops(mux->dev)->set(mux, state); > + > + mux->cached_state = ret < 0 ? MUX_CACHE_UNKNOWN : state; > + > + return ret; > +} > + > +unsigned int mux_control_states(struct mux_control *mux) > +{ > + return mux->states; > +} > + > +static int __mux_control_select(struct mux_control *mux, int state) > +{ > + int ret; > + > + if (WARN_ON(state < 0 || state >= mux->states)) > + return -EINVAL; > + > + if (mux->cached_state == state) > + return 0; > + > + ret = mux_control_set(mux, state); > + if (ret >= 0) > + return 0; > + > + /* The mux update failed, try to revert if appropriate... */ > + if (mux->idle_state != MUX_IDLE_AS_IS) > + mux_control_set(mux, mux->idle_state); > + > + return ret; > +} > + > +int mux_control_select(struct mux_control *mux, unsigned int state) > +{ > + int ret; > + > + if (mux->in_use) > + return -EBUSY; > + > + ret = __mux_control_select(mux, state); > + > + if (ret < 0) > + return ret; > + > + mux->in_use = true; > + > + return 0; > +} > + > +int mux_control_deselect(struct mux_control *mux) > +{ > + int ret = 0; > + > + if (mux->idle_state != MUX_IDLE_AS_IS && > + mux->idle_state != mux->cached_state) > + ret = mux_control_set(mux, mux->idle_state); > + > + mux->in_use = false; > + > + return ret; > +} > + > +static int mux_of_xlate_default(struct mux_chip *mux_chip, > + struct ofnode_phandle_args *args, > + struct mux_control **muxp) > +{ > + struct mux_control *mux; > + int id; > + > + debug("%s(mux=%p)\n", __func__, mux); > + > + if (args->args_count > 1) { > + debug("Invaild args_count: %d\n", args->args_count); > + return -EINVAL; > + } > + > + if (args->args_count) > + id = args->args[0]; > + else > + id = 0; > + > + if (id >= mux_chip->controllers) { > + dev_err(dev, "bad mux controller %u specified in %s\n", > + id, ofnode_get_name(args->node)); > + return -ERANGE; > + } > + > + mux = &mux_chip->mux[id]; > + mux->id = id; > + *muxp = mux; > + return 0; > +} > + > +static int mux_get_by_indexed_prop(struct udevice *dev, const char *prop_name, > + int index, struct mux_control **mux) > +{ > + int ret; > + struct ofnode_phandle_args args; > + struct udevice *dev_mux; > + const struct mux_control_ops *ops; > + struct mux_chip *mux_chip; > + > + debug("%s(dev=%p, index=%d, mux=%p)\n", __func__, dev, index, mux); > + > + ret = dev_read_phandle_with_args(dev, prop_name, "#mux-control-cells", > + 0, index, &args); > + if (ret) { > + debug("%s: fdtdec_parse_phandle_with_args failed: err=%d\n", > + __func__, ret); > + return ret; > + } > + > + ret = uclass_get_device_by_ofnode(UCLASS_MUX, args.node, &dev_mux); > + if (ret) { > + debug("%s: uclass_get_device_by_ofnode failed: err=%d\n", > + __func__, ret); > + return ret; > + } > + > + mux_chip = dev_get_uclass_priv(dev_mux); > + > + ops = mux_dev_ops(dev_mux); > + if (ops->of_xlate) > + ret = ops->of_xlate(mux_chip, &args, mux); > + else > + ret = mux_of_xlate_default(mux_chip, &args, mux); > + if (ret) { > + debug("of_xlate() failed: %d\n", ret); > + return ret; > + } > + (*mux)->dev = dev_mux; > + > + return 0; > +} > + > +int mux_get_by_index(struct udevice *dev, int index, struct mux_control **mux) > +{ > + return mux_get_by_indexed_prop(dev, "mux-controls", index, mux); > +} > + > +int mux_control_get(struct udevice *dev, const char *name, > + struct mux_control **mux) > +{ > + int index; > + > + debug("%s(dev=%p, name=%s, mux=%p)\n", __func__, dev, name, mux); > + > + index = dev_read_stringlist_search(dev, "mux-control-names", name); > + if (index < 0) { > + debug("fdt_stringlist_search() failed: %d\n", index); > + return index; > + } > + > + return mux_get_by_index(dev, index, mux); > +} > + > +void mux_control_put(struct mux_control *mux) > +{ > + mux_control_deselect(mux); > +} > + > +static void devm_mux_control_release(struct udevice *dev, void *res) > +{ > + mux_control_put(*(struct mux_control **)res); > +} > + > +struct mux_control *devm_mux_control_get(struct udevice *dev, const char *id) > +{ > + int rc; > + struct mux_control **mux; > + > + mux = devres_alloc(devm_mux_control_release, > + sizeof(struct mux_control *), __GFP_ZERO); > + if (unlikely(!mux)) > + return ERR_PTR(-ENOMEM); > + > + rc = mux_control_get(dev, id, mux); > + if (rc) > + return ERR_PTR(rc); > + > + devres_add(dev, mux); > + return *mux; > +} > + > +int mux_alloc_controllers(struct udevice *dev, unsigned int controllers) > +{ > + int i; > + struct mux_chip *mux_chip = dev_get_uclass_priv(dev); > + > + mux_chip->mux = devm_kmalloc(dev, > + sizeof(struct mux_control) * controllers, > + __GFP_ZERO); > + if (!mux_chip->mux) > + return -ENOMEM; > + > + mux_chip->controllers = controllers; > + > + for (i = 0; i < mux_chip->controllers; ++i) { > + struct mux_control *mux = &mux_chip->mux[i]; > + > + mux->dev = dev; > + mux->cached_state = MUX_CACHE_UNKNOWN; > + mux->idle_state = MUX_IDLE_AS_IS; > + mux->in_use = false; > + mux->id = i; > + } > + > + return 0; > +} > + > +int mux_uclass_post_probe(struct udevice *dev) > +{ > + int i, ret; > + struct mux_chip *mux_chip = dev_get_uclass_priv(dev); > + > + for (i = 0; i < mux_chip->controllers; ++i) { > + struct mux_control *mux = &mux_chip->mux[i]; > + > + if (mux->idle_state == mux->cached_state) > + continue; > + > + ret = mux_control_set(mux, mux->idle_state); > + if (ret < 0) { > + dev_err(&mux_chip->dev, "unable to set idle state\n"); > + return ret; > + } > + } > + return 0; > +} > + > +void dm_mux_init(void) > +{ > + struct uclass *uc; > + struct udevice *dev; > + int ret; > + > + ret = uclass_get(UCLASS_MUX, &uc); > + if (ret < 0) { > + debug("unable to get MUX uclass\n"); > + return; > + } > + uclass_foreach_dev(dev, uc) { > + if (dev_read_bool(dev, "u-boot,mux-autoprobe")) { > + ret = device_probe(dev); > + if (ret) > + debug("unable to probe device %s\n", dev->name); > + } else { > + printf("not found for dev %s\n", dev->name); > + } > + } > +} > + > +UCLASS_DRIVER(mux) = { > + .id = UCLASS_MUX, > + .name = "mux", > + .post_probe = mux_uclass_post_probe, > + .per_device_auto_alloc_size = sizeof(struct mux_chip), > +}; > diff --git a/include/dm/uclass-id.h b/include/dm/uclass-id.h > index d4d96106b3..869c0616bd 100644 > --- a/include/dm/uclass-id.h > +++ b/include/dm/uclass-id.h > @@ -64,6 +64,7 @@ enum uclass_id { > UCLASS_MMC, /* SD / MMC card or chip */ > UCLASS_MOD_EXP, /* RSA Mod Exp device */ > UCLASS_MTD, /* Memory Technology Device (MTD) device */ > + UCLASS_MUX, /* Multiplexer device */ > UCLASS_NOP, /* No-op devices */ > UCLASS_NORTHBRIDGE, /* Intel Northbridge / SDRAM controller */ > UCLASS_NVME, /* NVM Express device */ > diff --git a/include/dt-bindings/mux/mux.h b/include/dt-bindings/mux/mux.h > new file mode 100644 > index 0000000000..042719218d > --- /dev/null > +++ b/include/dt-bindings/mux/mux.h > @@ -0,0 +1,17 @@ > +/* SPDX-License-Identifier: GPL-2.0 */ > +/* > + * This header provides constants for most Multiplexer bindings. > + * > + * Most Multiplexer bindings specify an idle state. In most cases, the > + * the multiplexer can be left as is when idle, and in some cases it can > + * disconnect the input/output and leave the multiplexer in a high > + * impedance state. <add more details...what is a mux?> How do I use this API? > + */ > + > +#ifndef _DT_BINDINGS_MUX_MUX_H > +#define _DT_BINDINGS_MUX_MUX_H > + > +#define MUX_IDLE_AS_IS (-1) > +#define MUX_IDLE_DISCONNECT (-2) > + > +#endif > diff --git a/include/mux-internal.h b/include/mux-internal.h > new file mode 100644 > index 0000000000..63444f4c3d > --- /dev/null > +++ b/include/mux-internal.h > @@ -0,0 +1,80 @@ > +/* SPDX-License-Identifier: GPL-2.0+ */ > +/* > + * Based on the linux multiplexer framework > + * > + * Copyright (C) 2017 Axentia Technologies AB > + * Author: Peter Rosin <peda@axentia.se> > + * > + * Copyright (C) 2017-2018 Texas Instruments Incorporated - http://www.ti.com/ > + * Jean-Jacques Hiblot <jjhiblot@ti.com> > + */ > + > +#ifndef _MUX_UCLASS_H > +#define _MUX_UCLASS_H > + > +/* See mux.h for background documentation. */ > + > +#include <mux.h> > + > +struct ofnode_phandle_args; > + > +/** > + * struct mux_chip - Represents a chip holding mux controllers. > + * @controllers: Number of mux controllers handled by the chip. > + * @mux: Array of mux controllers that are handled. > + * @dev: Device structure. > + * @ops: Mux controller operations. Mention that this is per-device uclass-private data. > + */ > +struct mux_chip { > + unsigned int controllers; > + struct mux_control *mux; > +}; > + > +/** > + * struct mux_control_ops - Mux controller operations for a mux chip. > + * @set: Set the state of the given mux controller. > + */ > +struct mux_control_ops { > + int (*set)(struct mux_control *mux, int state); > + int (*of_xlate)(struct mux_chip *dev_mux, > + struct ofnode_phandle_args *args, > + struct mux_control **mux); Function comments > +}; > + > +/** > + * struct mux_control - Represents a mux controller. > + * @chip: The mux chip that is handling this mux controller. > + * @cached_state: The current mux controller state, or -1 if none. > + * @states: The number of mux controller states. > + * @idle_state: The mux controller state to use when inactive, or one > + * of MUX_IDLE_AS_IS and MUX_IDLE_DISCONNECT. > + * > + * Mux drivers may only change @states and @idle_state, and may only do so > + * between allocation and registration of the mux controller. Specifically, > + * @cached_state is internal to the mux core and should never be written by > + * mux drivers. How do I get from a struct udevice * to this struct? Is it private data? > + */ > +struct mux_control { > + bool in_use; > + struct udevice *dev; > + int cached_state; > + unsigned int states; > + int idle_state; > + int id; > +}; > + > +/** > + * mux_control_get_index() - Get the index of the given mux controller > + * @mux: The mux-control to get the index for. > + * > + * Return: The index of the mux controller within the mux chip the mux > + * controller is a part of. > + */ > +static inline unsigned int mux_control_get_index(struct mux_control *mux) > +{ > + return mux->id; > +} > + > +int mux_alloc_controllers(struct udevice *dev, unsigned int controllers); > + > +#endif [..] Regards, Simon
Hi Simon, Thank for the review. On 30/10/2019 02:48, Simon Glass wrote: > Hi Jean-Jacques, > > On Wed, 2 Oct 2019 at 06:47, Jean-Jacques Hiblot <jjhiblot@ti.com> wrote: >> Add a new subsystem that handles multiplexer controllers. The API is the >> same as in Linux. >> >> Signed-off-by: Jean-Jacques Hiblot <jjhiblot@ti.com> >> --- >> >> drivers/Kconfig | 2 + >> drivers/Makefile | 1 + >> drivers/mux/Kconfig | 7 + >> drivers/mux/Makefile | 6 + >> drivers/mux/mux-uclass.c | 296 ++++++++++++++++++++++++++++++++++ >> include/dm/uclass-id.h | 1 + >> include/dt-bindings/mux/mux.h | 17 ++ >> include/mux-internal.h | 80 +++++++++ >> include/mux.h | 114 +++++++++++++ >> 9 files changed, 524 insertions(+) >> create mode 100644 drivers/mux/Kconfig >> create mode 100644 drivers/mux/Makefile >> create mode 100644 drivers/mux/mux-uclass.c >> create mode 100644 include/dt-bindings/mux/mux.h >> create mode 100644 include/mux-internal.h >> create mode 100644 include/mux.h >> > I feel this needs more documentation. What is a multiplexer? I'll add a description of what a mux is in include/mux.h > >> diff --git a/drivers/Kconfig b/drivers/Kconfig >> index 350acf81f3..5334974ad4 100644 >> --- a/drivers/Kconfig >> +++ b/drivers/Kconfig >> @@ -60,6 +60,8 @@ source "drivers/mmc/Kconfig" >> >> source "drivers/mtd/Kconfig" >> >> +source "drivers/mux/Kconfig" >> + >> source "drivers/net/Kconfig" >> >> source "drivers/nvme/Kconfig" >> diff --git a/drivers/Makefile b/drivers/Makefile >> index a4bb5e4975..f4d71f3b3c 100644 >> --- a/drivers/Makefile >> +++ b/drivers/Makefile >> @@ -12,6 +12,7 @@ obj-$(CONFIG_$(SPL_TPL_)INPUT) += input/ >> obj-$(CONFIG_$(SPL_TPL_)LED) += led/ >> obj-$(CONFIG_$(SPL_TPL_)MMC_SUPPORT) += mmc/ >> obj-$(CONFIG_$(SPL_TPL_)NAND_SUPPORT) += mtd/nand/raw/ >> +obj-$(CONFIG_$(SPl_)MULTIPLEXER) += mux/ > SPL? good catch > >> obj-$(CONFIG_$(SPL_TPL_)PCH_SUPPORT) += pch/ >> obj-$(CONFIG_$(SPL_TPL_)PCI) += pci/ >> obj-$(CONFIG_$(SPL_TPL_)PHY) += phy/ >> diff --git a/drivers/mux/Kconfig b/drivers/mux/Kconfig >> new file mode 100644 >> index 0000000000..ad0199c058 >> --- /dev/null >> +++ b/drivers/mux/Kconfig >> @@ -0,0 +1,7 @@ >> +menu "Multiplexer drivers" >> + >> +config MULTIPLEXER >> + bool "Multiplexer Support" >> + depends on DM >> + >> +endmenu >> diff --git a/drivers/mux/Makefile b/drivers/mux/Makefile >> new file mode 100644 >> index 0000000000..351e4363d3 >> --- /dev/null >> +++ b/drivers/mux/Makefile >> @@ -0,0 +1,6 @@ >> +# SPDX-License-Identifier: GPL-2.0+ >> +# >> +# (C) Copyright 2019 >> +# Jean-Jacques Hiblot <jjhiblot@ti.com> >> + >> +obj-$(CONFIG_$(SPL_)MULTIPLEXER) += mux-uclass.o >> diff --git a/drivers/mux/mux-uclass.c b/drivers/mux/mux-uclass.c >> new file mode 100644 >> index 0000000000..58998af29c >> --- /dev/null >> +++ b/drivers/mux/mux-uclass.c >> @@ -0,0 +1,296 @@ >> +// SPDX-License-Identifier: GPL-2.0 >> +/* >> + * Multiplexer subsystem >> + * >> + * Based on the linux multiplexer framework >> + * >> + * Copyright (C) 2017 Axentia Technologies AB >> + * Author: Peter Rosin <peda@axentia.se> >> + * >> + * Copyright (C) 2017-2018 Texas Instruments Incorporated - http://www.ti.com/ >> + * Jean-Jacques Hiblot <jjhiblot@ti.com> >> + */ >> + >> +#include <common.h> >> +#include <mux-internal.h> > should go above the dm/device-internal > >> +#include <dm.h> >> +#include <dt-structs.h> > Shouldn't need this >> +#include <errno.h> > Shouldn't need this > >> +#include <dm/device-internal.h> >> +#include <dm/lists.h> >> +#include <dm/read.h> > Shouldn't need this I'll cleanup the headers in v2. > >> +#include <dt-bindings/mux/mux.h> >> + >> +/* >> + * The idle-as-is "state" is not an actual state that may be selected, it >> + * only implies that the state should not be changed. So, use that state >> + * as indication that the cached state of the multiplexer is unknown. >> + */ >> +#define MUX_CACHE_UNKNOWN MUX_IDLE_AS_IS >> + >> +static inline const struct mux_control_ops *mux_dev_ops(struct udevice *dev) >> +{ >> + return (const struct mux_control_ops *)dev->driver->ops; >> +} >> + >> +static int mux_control_set(struct mux_control *mux, int state) >> +{ >> + int ret = mux_dev_ops(mux->dev)->set(mux, state); >> + >> + mux->cached_state = ret < 0 ? MUX_CACHE_UNKNOWN : state; >> + >> + return ret; >> +} >> + >> +unsigned int mux_control_states(struct mux_control *mux) >> +{ >> + return mux->states; >> +} >> + >> +static int __mux_control_select(struct mux_control *mux, int state) >> +{ >> + int ret; >> + >> + if (WARN_ON(state < 0 || state >= mux->states)) >> + return -EINVAL; >> + >> + if (mux->cached_state == state) >> + return 0; >> + >> + ret = mux_control_set(mux, state); >> + if (ret >= 0) >> + return 0; >> + >> + /* The mux update failed, try to revert if appropriate... */ >> + if (mux->idle_state != MUX_IDLE_AS_IS) >> + mux_control_set(mux, mux->idle_state); >> + >> + return ret; >> +} >> + >> +int mux_control_select(struct mux_control *mux, unsigned int state) >> +{ >> + int ret; >> + >> + if (mux->in_use) >> + return -EBUSY; >> + >> + ret = __mux_control_select(mux, state); >> + >> + if (ret < 0) >> + return ret; >> + >> + mux->in_use = true; >> + >> + return 0; >> +} >> + >> +int mux_control_deselect(struct mux_control *mux) >> +{ >> + int ret = 0; >> + >> + if (mux->idle_state != MUX_IDLE_AS_IS && >> + mux->idle_state != mux->cached_state) >> + ret = mux_control_set(mux, mux->idle_state); >> + >> + mux->in_use = false; >> + >> + return ret; >> +} >> + >> +static int mux_of_xlate_default(struct mux_chip *mux_chip, >> + struct ofnode_phandle_args *args, >> + struct mux_control **muxp) >> +{ >> + struct mux_control *mux; >> + int id; >> + >> + debug("%s(mux=%p)\n", __func__, mux); >> + >> + if (args->args_count > 1) { >> + debug("Invaild args_count: %d\n", args->args_count); >> + return -EINVAL; >> + } >> + >> + if (args->args_count) >> + id = args->args[0]; >> + else >> + id = 0; >> + >> + if (id >= mux_chip->controllers) { >> + dev_err(dev, "bad mux controller %u specified in %s\n", >> + id, ofnode_get_name(args->node)); >> + return -ERANGE; >> + } >> + >> + mux = &mux_chip->mux[id]; >> + mux->id = id; >> + *muxp = mux; >> + return 0; >> +} >> + >> +static int mux_get_by_indexed_prop(struct udevice *dev, const char *prop_name, >> + int index, struct mux_control **mux) >> +{ >> + int ret; >> + struct ofnode_phandle_args args; >> + struct udevice *dev_mux; >> + const struct mux_control_ops *ops; >> + struct mux_chip *mux_chip; >> + >> + debug("%s(dev=%p, index=%d, mux=%p)\n", __func__, dev, index, mux); >> + >> + ret = dev_read_phandle_with_args(dev, prop_name, "#mux-control-cells", >> + 0, index, &args); >> + if (ret) { >> + debug("%s: fdtdec_parse_phandle_with_args failed: err=%d\n", >> + __func__, ret); >> + return ret; >> + } >> + >> + ret = uclass_get_device_by_ofnode(UCLASS_MUX, args.node, &dev_mux); >> + if (ret) { >> + debug("%s: uclass_get_device_by_ofnode failed: err=%d\n", >> + __func__, ret); >> + return ret; >> + } >> + >> + mux_chip = dev_get_uclass_priv(dev_mux); >> + >> + ops = mux_dev_ops(dev_mux); >> + if (ops->of_xlate) >> + ret = ops->of_xlate(mux_chip, &args, mux); >> + else >> + ret = mux_of_xlate_default(mux_chip, &args, mux); >> + if (ret) { >> + debug("of_xlate() failed: %d\n", ret); >> + return ret; >> + } >> + (*mux)->dev = dev_mux; >> + >> + return 0; >> +} >> + >> +int mux_get_by_index(struct udevice *dev, int index, struct mux_control **mux) >> +{ >> + return mux_get_by_indexed_prop(dev, "mux-controls", index, mux); >> +} >> + >> +int mux_control_get(struct udevice *dev, const char *name, >> + struct mux_control **mux) >> +{ >> + int index; >> + >> + debug("%s(dev=%p, name=%s, mux=%p)\n", __func__, dev, name, mux); >> + >> + index = dev_read_stringlist_search(dev, "mux-control-names", name); >> + if (index < 0) { >> + debug("fdt_stringlist_search() failed: %d\n", index); >> + return index; >> + } >> + >> + return mux_get_by_index(dev, index, mux); >> +} >> + >> +void mux_control_put(struct mux_control *mux) >> +{ >> + mux_control_deselect(mux); >> +} >> + >> +static void devm_mux_control_release(struct udevice *dev, void *res) >> +{ >> + mux_control_put(*(struct mux_control **)res); >> +} >> + >> +struct mux_control *devm_mux_control_get(struct udevice *dev, const char *id) >> +{ >> + int rc; >> + struct mux_control **mux; >> + >> + mux = devres_alloc(devm_mux_control_release, >> + sizeof(struct mux_control *), __GFP_ZERO); >> + if (unlikely(!mux)) >> + return ERR_PTR(-ENOMEM); >> + >> + rc = mux_control_get(dev, id, mux); >> + if (rc) >> + return ERR_PTR(rc); >> + >> + devres_add(dev, mux); >> + return *mux; >> +} >> + >> +int mux_alloc_controllers(struct udevice *dev, unsigned int controllers) >> +{ >> + int i; >> + struct mux_chip *mux_chip = dev_get_uclass_priv(dev); >> + >> + mux_chip->mux = devm_kmalloc(dev, >> + sizeof(struct mux_control) * controllers, >> + __GFP_ZERO); >> + if (!mux_chip->mux) >> + return -ENOMEM; >> + >> + mux_chip->controllers = controllers; >> + >> + for (i = 0; i < mux_chip->controllers; ++i) { >> + struct mux_control *mux = &mux_chip->mux[i]; >> + >> + mux->dev = dev; >> + mux->cached_state = MUX_CACHE_UNKNOWN; >> + mux->idle_state = MUX_IDLE_AS_IS; >> + mux->in_use = false; >> + mux->id = i; >> + } >> + >> + return 0; >> +} >> + >> +int mux_uclass_post_probe(struct udevice *dev) >> +{ >> + int i, ret; >> + struct mux_chip *mux_chip = dev_get_uclass_priv(dev); >> + >> + for (i = 0; i < mux_chip->controllers; ++i) { >> + struct mux_control *mux = &mux_chip->mux[i]; >> + >> + if (mux->idle_state == mux->cached_state) >> + continue; >> + >> + ret = mux_control_set(mux, mux->idle_state); >> + if (ret < 0) { >> + dev_err(&mux_chip->dev, "unable to set idle state\n"); >> + return ret; >> + } >> + } >> + return 0; >> +} >> + >> +void dm_mux_init(void) >> +{ >> + struct uclass *uc; >> + struct udevice *dev; >> + int ret; >> + >> + ret = uclass_get(UCLASS_MUX, &uc); >> + if (ret < 0) { >> + debug("unable to get MUX uclass\n"); >> + return; >> + } >> + uclass_foreach_dev(dev, uc) { >> + if (dev_read_bool(dev, "u-boot,mux-autoprobe")) { >> + ret = device_probe(dev); >> + if (ret) >> + debug("unable to probe device %s\n", dev->name); >> + } else { >> + printf("not found for dev %s\n", dev->name); >> + } >> + } >> +} >> + >> +UCLASS_DRIVER(mux) = { >> + .id = UCLASS_MUX, >> + .name = "mux", >> + .post_probe = mux_uclass_post_probe, >> + .per_device_auto_alloc_size = sizeof(struct mux_chip), >> +}; >> diff --git a/include/dm/uclass-id.h b/include/dm/uclass-id.h >> index d4d96106b3..869c0616bd 100644 >> --- a/include/dm/uclass-id.h >> +++ b/include/dm/uclass-id.h >> @@ -64,6 +64,7 @@ enum uclass_id { >> UCLASS_MMC, /* SD / MMC card or chip */ >> UCLASS_MOD_EXP, /* RSA Mod Exp device */ >> UCLASS_MTD, /* Memory Technology Device (MTD) device */ >> + UCLASS_MUX, /* Multiplexer device */ >> UCLASS_NOP, /* No-op devices */ >> UCLASS_NORTHBRIDGE, /* Intel Northbridge / SDRAM controller */ >> UCLASS_NVME, /* NVM Express device */ >> diff --git a/include/dt-bindings/mux/mux.h b/include/dt-bindings/mux/mux.h >> new file mode 100644 >> index 0000000000..042719218d >> --- /dev/null >> +++ b/include/dt-bindings/mux/mux.h >> @@ -0,0 +1,17 @@ >> +/* SPDX-License-Identifier: GPL-2.0 */ >> +/* >> + * This header provides constants for most Multiplexer bindings. >> + * >> + * Most Multiplexer bindings specify an idle state. In most cases, the >> + * the multiplexer can be left as is when idle, and in some cases it can >> + * disconnect the input/output and leave the multiplexer in a high >> + * impedance state. > <add more details...what is a mux?> > > How do I use this API? The API is described by the comments in include/mux.h > >> + */ >> + >> +#ifndef _DT_BINDINGS_MUX_MUX_H >> +#define _DT_BINDINGS_MUX_MUX_H >> + >> +#define MUX_IDLE_AS_IS (-1) >> +#define MUX_IDLE_DISCONNECT (-2) >> + >> +#endif >> diff --git a/include/mux-internal.h b/include/mux-internal.h >> new file mode 100644 >> index 0000000000..63444f4c3d >> --- /dev/null >> +++ b/include/mux-internal.h >> @@ -0,0 +1,80 @@ >> +/* SPDX-License-Identifier: GPL-2.0+ */ >> +/* >> + * Based on the linux multiplexer framework >> + * >> + * Copyright (C) 2017 Axentia Technologies AB >> + * Author: Peter Rosin <peda@axentia.se> >> + * >> + * Copyright (C) 2017-2018 Texas Instruments Incorporated - http://www.ti.com/ >> + * Jean-Jacques Hiblot <jjhiblot@ti.com> >> + */ >> + >> +#ifndef _MUX_UCLASS_H >> +#define _MUX_UCLASS_H >> + >> +/* See mux.h for background documentation. */ >> + >> +#include <mux.h> >> + >> +struct ofnode_phandle_args; >> + >> +/** >> + * struct mux_chip - Represents a chip holding mux controllers. >> + * @controllers: Number of mux controllers handled by the chip. >> + * @mux: Array of mux controllers that are handled. >> + * @dev: Device structure. >> + * @ops: Mux controller operations. > Mention that this is per-device uclass-private data. > >> + */ >> +struct mux_chip { >> + unsigned int controllers; >> + struct mux_control *mux; >> +}; >> + >> +/** >> + * struct mux_control_ops - Mux controller operations for a mux chip. >> + * @set: Set the state of the given mux controller. >> + */ >> +struct mux_control_ops { >> + int (*set)(struct mux_control *mux, int state); >> + int (*of_xlate)(struct mux_chip *dev_mux, >> + struct ofnode_phandle_args *args, >> + struct mux_control **mux); > Function comments > >> +}; >> + >> +/** >> + * struct mux_control - Represents a mux controller. >> + * @chip: The mux chip that is handling this mux controller. >> + * @cached_state: The current mux controller state, or -1 if none. >> + * @states: The number of mux controller states. >> + * @idle_state: The mux controller state to use when inactive, or one >> + * of MUX_IDLE_AS_IS and MUX_IDLE_DISCONNECT. >> + * >> + * Mux drivers may only change @states and @idle_state, and may only do so >> + * between allocation and registration of the mux controller. Specifically, >> + * @cached_state is internal to the mux core and should never be written by >> + * mux drivers. > How do I get from a struct udevice * to this struct? Is it private data? This is not private data per-se. It is intended to be used by a client device. You get a mux_control* with mux_control_get() and devm_mux_control_get(). JJ > >> + */ >> +struct mux_control { >> + bool in_use; >> + struct udevice *dev; >> + int cached_state; >> + unsigned int states; >> + int idle_state; >> + int id; >> +}; >> + >> +/** >> + * mux_control_get_index() - Get the index of the given mux controller >> + * @mux: The mux-control to get the index for. >> + * >> + * Return: The index of the mux controller within the mux chip the mux >> + * controller is a part of. >> + */ >> +static inline unsigned int mux_control_get_index(struct mux_control *mux) >> +{ >> + return mux->id; >> +} >> + >> +int mux_alloc_controllers(struct udevice *dev, unsigned int controllers); >> + >> +#endif > [..] > > Regards, > Simon >
+Alex who once worked in MUX on LS1028 IIRC. On Wed, Oct 2, 2019 at 8:47 PM Jean-Jacques Hiblot <jjhiblot@ti.com> wrote: > > Add a new subsystem that handles multiplexer controllers. The API is the > same as in Linux. > > Signed-off-by: Jean-Jacques Hiblot <jjhiblot@ti.com> > --- > > drivers/Kconfig | 2 + > drivers/Makefile | 1 + > drivers/mux/Kconfig | 7 + > drivers/mux/Makefile | 6 + > drivers/mux/mux-uclass.c | 296 ++++++++++++++++++++++++++++++++++ > include/dm/uclass-id.h | 1 + > include/dt-bindings/mux/mux.h | 17 ++ > include/mux-internal.h | 80 +++++++++ > include/mux.h | 114 +++++++++++++ > 9 files changed, 524 insertions(+) > create mode 100644 drivers/mux/Kconfig > create mode 100644 drivers/mux/Makefile > create mode 100644 drivers/mux/mux-uclass.c > create mode 100644 include/dt-bindings/mux/mux.h > create mode 100644 include/mux-internal.h > create mode 100644 include/mux.h > Regards, Bin
diff --git a/drivers/Kconfig b/drivers/Kconfig index 350acf81f3..5334974ad4 100644 --- a/drivers/Kconfig +++ b/drivers/Kconfig @@ -60,6 +60,8 @@ source "drivers/mmc/Kconfig" source "drivers/mtd/Kconfig" +source "drivers/mux/Kconfig" + source "drivers/net/Kconfig" source "drivers/nvme/Kconfig" diff --git a/drivers/Makefile b/drivers/Makefile index a4bb5e4975..f4d71f3b3c 100644 --- a/drivers/Makefile +++ b/drivers/Makefile @@ -12,6 +12,7 @@ obj-$(CONFIG_$(SPL_TPL_)INPUT) += input/ obj-$(CONFIG_$(SPL_TPL_)LED) += led/ obj-$(CONFIG_$(SPL_TPL_)MMC_SUPPORT) += mmc/ obj-$(CONFIG_$(SPL_TPL_)NAND_SUPPORT) += mtd/nand/raw/ +obj-$(CONFIG_$(SPl_)MULTIPLEXER) += mux/ obj-$(CONFIG_$(SPL_TPL_)PCH_SUPPORT) += pch/ obj-$(CONFIG_$(SPL_TPL_)PCI) += pci/ obj-$(CONFIG_$(SPL_TPL_)PHY) += phy/ diff --git a/drivers/mux/Kconfig b/drivers/mux/Kconfig new file mode 100644 index 0000000000..ad0199c058 --- /dev/null +++ b/drivers/mux/Kconfig @@ -0,0 +1,7 @@ +menu "Multiplexer drivers" + +config MULTIPLEXER + bool "Multiplexer Support" + depends on DM + +endmenu diff --git a/drivers/mux/Makefile b/drivers/mux/Makefile new file mode 100644 index 0000000000..351e4363d3 --- /dev/null +++ b/drivers/mux/Makefile @@ -0,0 +1,6 @@ +# SPDX-License-Identifier: GPL-2.0+ +# +# (C) Copyright 2019 +# Jean-Jacques Hiblot <jjhiblot@ti.com> + +obj-$(CONFIG_$(SPL_)MULTIPLEXER) += mux-uclass.o diff --git a/drivers/mux/mux-uclass.c b/drivers/mux/mux-uclass.c new file mode 100644 index 0000000000..58998af29c --- /dev/null +++ b/drivers/mux/mux-uclass.c @@ -0,0 +1,296 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * Multiplexer subsystem + * + * Based on the linux multiplexer framework + * + * Copyright (C) 2017 Axentia Technologies AB + * Author: Peter Rosin <peda@axentia.se> + * + * Copyright (C) 2017-2018 Texas Instruments Incorporated - http://www.ti.com/ + * Jean-Jacques Hiblot <jjhiblot@ti.com> + */ + +#include <common.h> +#include <mux-internal.h> +#include <dm.h> +#include <dt-structs.h> +#include <errno.h> +#include <dm/device-internal.h> +#include <dm/lists.h> +#include <dm/read.h> +#include <dt-bindings/mux/mux.h> + +/* + * The idle-as-is "state" is not an actual state that may be selected, it + * only implies that the state should not be changed. So, use that state + * as indication that the cached state of the multiplexer is unknown. + */ +#define MUX_CACHE_UNKNOWN MUX_IDLE_AS_IS + +static inline const struct mux_control_ops *mux_dev_ops(struct udevice *dev) +{ + return (const struct mux_control_ops *)dev->driver->ops; +} + +static int mux_control_set(struct mux_control *mux, int state) +{ + int ret = mux_dev_ops(mux->dev)->set(mux, state); + + mux->cached_state = ret < 0 ? MUX_CACHE_UNKNOWN : state; + + return ret; +} + +unsigned int mux_control_states(struct mux_control *mux) +{ + return mux->states; +} + +static int __mux_control_select(struct mux_control *mux, int state) +{ + int ret; + + if (WARN_ON(state < 0 || state >= mux->states)) + return -EINVAL; + + if (mux->cached_state == state) + return 0; + + ret = mux_control_set(mux, state); + if (ret >= 0) + return 0; + + /* The mux update failed, try to revert if appropriate... */ + if (mux->idle_state != MUX_IDLE_AS_IS) + mux_control_set(mux, mux->idle_state); + + return ret; +} + +int mux_control_select(struct mux_control *mux, unsigned int state) +{ + int ret; + + if (mux->in_use) + return -EBUSY; + + ret = __mux_control_select(mux, state); + + if (ret < 0) + return ret; + + mux->in_use = true; + + return 0; +} + +int mux_control_deselect(struct mux_control *mux) +{ + int ret = 0; + + if (mux->idle_state != MUX_IDLE_AS_IS && + mux->idle_state != mux->cached_state) + ret = mux_control_set(mux, mux->idle_state); + + mux->in_use = false; + + return ret; +} + +static int mux_of_xlate_default(struct mux_chip *mux_chip, + struct ofnode_phandle_args *args, + struct mux_control **muxp) +{ + struct mux_control *mux; + int id; + + debug("%s(mux=%p)\n", __func__, mux); + + if (args->args_count > 1) { + debug("Invaild args_count: %d\n", args->args_count); + return -EINVAL; + } + + if (args->args_count) + id = args->args[0]; + else + id = 0; + + if (id >= mux_chip->controllers) { + dev_err(dev, "bad mux controller %u specified in %s\n", + id, ofnode_get_name(args->node)); + return -ERANGE; + } + + mux = &mux_chip->mux[id]; + mux->id = id; + *muxp = mux; + return 0; +} + +static int mux_get_by_indexed_prop(struct udevice *dev, const char *prop_name, + int index, struct mux_control **mux) +{ + int ret; + struct ofnode_phandle_args args; + struct udevice *dev_mux; + const struct mux_control_ops *ops; + struct mux_chip *mux_chip; + + debug("%s(dev=%p, index=%d, mux=%p)\n", __func__, dev, index, mux); + + ret = dev_read_phandle_with_args(dev, prop_name, "#mux-control-cells", + 0, index, &args); + if (ret) { + debug("%s: fdtdec_parse_phandle_with_args failed: err=%d\n", + __func__, ret); + return ret; + } + + ret = uclass_get_device_by_ofnode(UCLASS_MUX, args.node, &dev_mux); + if (ret) { + debug("%s: uclass_get_device_by_ofnode failed: err=%d\n", + __func__, ret); + return ret; + } + + mux_chip = dev_get_uclass_priv(dev_mux); + + ops = mux_dev_ops(dev_mux); + if (ops->of_xlate) + ret = ops->of_xlate(mux_chip, &args, mux); + else + ret = mux_of_xlate_default(mux_chip, &args, mux); + if (ret) { + debug("of_xlate() failed: %d\n", ret); + return ret; + } + (*mux)->dev = dev_mux; + + return 0; +} + +int mux_get_by_index(struct udevice *dev, int index, struct mux_control **mux) +{ + return mux_get_by_indexed_prop(dev, "mux-controls", index, mux); +} + +int mux_control_get(struct udevice *dev, const char *name, + struct mux_control **mux) +{ + int index; + + debug("%s(dev=%p, name=%s, mux=%p)\n", __func__, dev, name, mux); + + index = dev_read_stringlist_search(dev, "mux-control-names", name); + if (index < 0) { + debug("fdt_stringlist_search() failed: %d\n", index); + return index; + } + + return mux_get_by_index(dev, index, mux); +} + +void mux_control_put(struct mux_control *mux) +{ + mux_control_deselect(mux); +} + +static void devm_mux_control_release(struct udevice *dev, void *res) +{ + mux_control_put(*(struct mux_control **)res); +} + +struct mux_control *devm_mux_control_get(struct udevice *dev, const char *id) +{ + int rc; + struct mux_control **mux; + + mux = devres_alloc(devm_mux_control_release, + sizeof(struct mux_control *), __GFP_ZERO); + if (unlikely(!mux)) + return ERR_PTR(-ENOMEM); + + rc = mux_control_get(dev, id, mux); + if (rc) + return ERR_PTR(rc); + + devres_add(dev, mux); + return *mux; +} + +int mux_alloc_controllers(struct udevice *dev, unsigned int controllers) +{ + int i; + struct mux_chip *mux_chip = dev_get_uclass_priv(dev); + + mux_chip->mux = devm_kmalloc(dev, + sizeof(struct mux_control) * controllers, + __GFP_ZERO); + if (!mux_chip->mux) + return -ENOMEM; + + mux_chip->controllers = controllers; + + for (i = 0; i < mux_chip->controllers; ++i) { + struct mux_control *mux = &mux_chip->mux[i]; + + mux->dev = dev; + mux->cached_state = MUX_CACHE_UNKNOWN; + mux->idle_state = MUX_IDLE_AS_IS; + mux->in_use = false; + mux->id = i; + } + + return 0; +} + +int mux_uclass_post_probe(struct udevice *dev) +{ + int i, ret; + struct mux_chip *mux_chip = dev_get_uclass_priv(dev); + + for (i = 0; i < mux_chip->controllers; ++i) { + struct mux_control *mux = &mux_chip->mux[i]; + + if (mux->idle_state == mux->cached_state) + continue; + + ret = mux_control_set(mux, mux->idle_state); + if (ret < 0) { + dev_err(&mux_chip->dev, "unable to set idle state\n"); + return ret; + } + } + return 0; +} + +void dm_mux_init(void) +{ + struct uclass *uc; + struct udevice *dev; + int ret; + + ret = uclass_get(UCLASS_MUX, &uc); + if (ret < 0) { + debug("unable to get MUX uclass\n"); + return; + } + uclass_foreach_dev(dev, uc) { + if (dev_read_bool(dev, "u-boot,mux-autoprobe")) { + ret = device_probe(dev); + if (ret) + debug("unable to probe device %s\n", dev->name); + } else { + printf("not found for dev %s\n", dev->name); + } + } +} + +UCLASS_DRIVER(mux) = { + .id = UCLASS_MUX, + .name = "mux", + .post_probe = mux_uclass_post_probe, + .per_device_auto_alloc_size = sizeof(struct mux_chip), +}; diff --git a/include/dm/uclass-id.h b/include/dm/uclass-id.h index d4d96106b3..869c0616bd 100644 --- a/include/dm/uclass-id.h +++ b/include/dm/uclass-id.h @@ -64,6 +64,7 @@ enum uclass_id { UCLASS_MMC, /* SD / MMC card or chip */ UCLASS_MOD_EXP, /* RSA Mod Exp device */ UCLASS_MTD, /* Memory Technology Device (MTD) device */ + UCLASS_MUX, /* Multiplexer device */ UCLASS_NOP, /* No-op devices */ UCLASS_NORTHBRIDGE, /* Intel Northbridge / SDRAM controller */ UCLASS_NVME, /* NVM Express device */ diff --git a/include/dt-bindings/mux/mux.h b/include/dt-bindings/mux/mux.h new file mode 100644 index 0000000000..042719218d --- /dev/null +++ b/include/dt-bindings/mux/mux.h @@ -0,0 +1,17 @@ +/* SPDX-License-Identifier: GPL-2.0 */ +/* + * This header provides constants for most Multiplexer bindings. + * + * Most Multiplexer bindings specify an idle state. In most cases, the + * the multiplexer can be left as is when idle, and in some cases it can + * disconnect the input/output and leave the multiplexer in a high + * impedance state. + */ + +#ifndef _DT_BINDINGS_MUX_MUX_H +#define _DT_BINDINGS_MUX_MUX_H + +#define MUX_IDLE_AS_IS (-1) +#define MUX_IDLE_DISCONNECT (-2) + +#endif diff --git a/include/mux-internal.h b/include/mux-internal.h new file mode 100644 index 0000000000..63444f4c3d --- /dev/null +++ b/include/mux-internal.h @@ -0,0 +1,80 @@ +/* SPDX-License-Identifier: GPL-2.0+ */ +/* + * Based on the linux multiplexer framework + * + * Copyright (C) 2017 Axentia Technologies AB + * Author: Peter Rosin <peda@axentia.se> + * + * Copyright (C) 2017-2018 Texas Instruments Incorporated - http://www.ti.com/ + * Jean-Jacques Hiblot <jjhiblot@ti.com> + */ + +#ifndef _MUX_UCLASS_H +#define _MUX_UCLASS_H + +/* See mux.h for background documentation. */ + +#include <mux.h> + +struct ofnode_phandle_args; + +/** + * struct mux_chip - Represents a chip holding mux controllers. + * @controllers: Number of mux controllers handled by the chip. + * @mux: Array of mux controllers that are handled. + * @dev: Device structure. + * @ops: Mux controller operations. + */ +struct mux_chip { + unsigned int controllers; + struct mux_control *mux; +}; + +/** + * struct mux_control_ops - Mux controller operations for a mux chip. + * @set: Set the state of the given mux controller. + */ +struct mux_control_ops { + int (*set)(struct mux_control *mux, int state); + int (*of_xlate)(struct mux_chip *dev_mux, + struct ofnode_phandle_args *args, + struct mux_control **mux); +}; + +/** + * struct mux_control - Represents a mux controller. + * @chip: The mux chip that is handling this mux controller. + * @cached_state: The current mux controller state, or -1 if none. + * @states: The number of mux controller states. + * @idle_state: The mux controller state to use when inactive, or one + * of MUX_IDLE_AS_IS and MUX_IDLE_DISCONNECT. + * + * Mux drivers may only change @states and @idle_state, and may only do so + * between allocation and registration of the mux controller. Specifically, + * @cached_state is internal to the mux core and should never be written by + * mux drivers. + */ +struct mux_control { + bool in_use; + struct udevice *dev; + int cached_state; + unsigned int states; + int idle_state; + int id; +}; + +/** + * mux_control_get_index() - Get the index of the given mux controller + * @mux: The mux-control to get the index for. + * + * Return: The index of the mux controller within the mux chip the mux + * controller is a part of. + */ +static inline unsigned int mux_control_get_index(struct mux_control *mux) +{ + return mux->id; +} + +int mux_alloc_controllers(struct udevice *dev, unsigned int controllers); + +#endif diff --git a/include/mux.h b/include/mux.h new file mode 100644 index 0000000000..d9d7728fea --- /dev/null +++ b/include/mux.h @@ -0,0 +1,114 @@ +/* SPDX-License-Identifier: GPL-2.0+ */ +/* + * Based on the linux multiplexer framework + * + * Copyright (C) 2017 Axentia Technologies AB + * Author: Peter Rosin <peda@axentia.se> + * + * Copyright (C) 2017-2018 Texas Instruments Incorporated - http://www.ti.com/ + * Jean-Jacques Hiblot <jjhiblot@ti.com> + */ + +#ifndef _MUX_H_ +#define _MUX_H_ + +#include <linux/errno.h> +#include <linux/types.h> + +struct udevice; +struct mux_control; + +#if CONFIG_IS_ENABLED(MULTIPLEXER) +/** + * mux_control_states() - Query the number of multiplexer states. + * @mux: The mux-control to query. + * + * Return: The number of multiplexer states. + */ +unsigned int mux_control_states(struct mux_control *mux); + +/** + * mux_control_select() - Select the given multiplexer state. + * @mux: The mux-control to request a change of state from. + * @state: The new requested state. + * + * On successfully selecting the mux-control state, it will be locked until + * there is a call to mux_control_deselect(). If the mux-control is already + * selected when mux_control_select() is called, the function will indicate + * -EBUSY + * + * Therefore, make sure to call mux_control_deselect() when the operation is + * complete and the mux-control is free for others to use, but do not call + * mux_control_deselect() if mux_control_select() fails. + * + * Return: 0 when the mux-control state has the requested state or a negative + * errno on error. + */ +int __must_check mux_control_select(struct mux_control *mux, + unsigned int state); +#define mux_control_try_select(mux) mux_control_select(mux) + +/** + * mux_control_deselect() - Deselect the previously selected multiplexer state. + * @mux: The mux-control to deselect. + * + * It is required that a single call is made to mux_control_deselect() for + * each and every successful call made to either of mux_control_select() or + * mux_control_try_select(). + * + * Return: 0 on success and a negative errno on error. An error can only + * occur if the mux has an idle state. Note that even if an error occurs, the + * mux-control is unlocked and is thus free for the next access. + */ +int mux_control_deselect(struct mux_control *mux); + +int mux_get_by_index(struct udevice *dev, int index, struct mux_control **mux); +int mux_control_get(struct udevice *dev, const char *name, + struct mux_control **mux); + +void mux_control_put(struct mux_control *mux); + +struct mux_control *devm_mux_control_get(struct udevice *dev, + const char *mux_name); + +void dm_mux_init(void); +#else +unsigned int mux_control_states(struct mux_control *mux) +{ + return -ENOSYS; +} + +int __must_check mux_control_select(struct mux_control *mux, + unsigned int state) +{ + return -ENOSYS; +} + +#define mux_control_try_select(mux) mux_control_select(mux) + +int mux_control_deselect(struct mux_control *mux) +{ + return -ENOSYS; +} + +struct mux_control *mux_control_get(struct udevice *dev, const char *mux_name) +{ + return NULL; +} + +void mux_control_put(struct mux_control *mux) +{ +} + +struct mux_control *devm_mux_control_get(struct udevice *dev, + const char *mux_name) +{ + return NULL; +} + +void dm_mux_init(void) +{ +} +#endif + +#endif
Add a new subsystem that handles multiplexer controllers. The API is the same as in Linux. Signed-off-by: Jean-Jacques Hiblot <jjhiblot@ti.com> --- drivers/Kconfig | 2 + drivers/Makefile | 1 + drivers/mux/Kconfig | 7 + drivers/mux/Makefile | 6 + drivers/mux/mux-uclass.c | 296 ++++++++++++++++++++++++++++++++++ include/dm/uclass-id.h | 1 + include/dt-bindings/mux/mux.h | 17 ++ include/mux-internal.h | 80 +++++++++ include/mux.h | 114 +++++++++++++ 9 files changed, 524 insertions(+) create mode 100644 drivers/mux/Kconfig create mode 100644 drivers/mux/Makefile create mode 100644 drivers/mux/mux-uclass.c create mode 100644 include/dt-bindings/mux/mux.h create mode 100644 include/mux-internal.h create mode 100644 include/mux.h