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];elseid = 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);elseret = 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