Many SoCs have a number of system controllers which are dealt with as a group by a single driver. It is a pain to have to add lots of compatible strings and/or separate drivers for each. Instead we can identify the controllers by a number and request the address of the one we want.
Add a simple implementation of this which can be used by SoC driver code.
Signed-off-by: Simon Glass sjg@chromium.org ---
Changes in v3: None Changes in v2: None
drivers/core/Makefile | 1 + drivers/core/syscon-uclass.c | 73 ++++++++++++++++++++++++++++++++++++++++++++ include/dm/uclass-id.h | 1 + include/syscon.h | 56 +++++++++++++++++++++++++++++++++ 4 files changed, 131 insertions(+) create mode 100644 drivers/core/syscon-uclass.c create mode 100644 include/syscon.h
diff --git a/drivers/core/Makefile b/drivers/core/Makefile index 7851824..54d57e5 100644 --- a/drivers/core/Makefile +++ b/drivers/core/Makefile @@ -11,3 +11,4 @@ endif obj-$(CONFIG_DM_DEVICE_REMOVE) += device-remove.o obj-$(CONFIG_DM) += dump.o obj-$(CONFIG_OF_CONTROL) += regmap.o +obj-$(CONFIG_OF_CONTROL) += syscon-uclass.o diff --git a/drivers/core/syscon-uclass.c b/drivers/core/syscon-uclass.c new file mode 100644 index 0000000..4d66bb5 --- /dev/null +++ b/drivers/core/syscon-uclass.c @@ -0,0 +1,73 @@ +/* + * Copyright (C) 2015 Google, Inc + * Written by Simon Glass sjg@chromium.org + * + * SPDX-License-Identifier: GPL-2.0+ + */ + +#include <common.h> +#include <syscon.h> +#include <dm.h> +#include <errno.h> +#include <regmap.h> +#include <dm/device-internal.h> +#include <dm/lists.h> +#include <dm/root.h> +#include <linux/err.h> + +struct regmap *syscon_get_regmap(struct udevice *dev) +{ + struct syscon_uc_info *priv = dev_get_uclass_priv(dev); + + return priv->regmap; +} + +static int syscon_pre_probe(struct udevice *dev) +{ + struct syscon_uc_info *priv = dev_get_uclass_priv(dev); + + return regmap_init_mem(dev, &priv->regmap); +} + +struct regmap *syscon_get_regmap_by_driver_data(ulong driver_data) +{ + struct udevice *dev; + struct uclass *uc; + int ret; + + ret = uclass_get(UCLASS_SYSCON, &uc); + if (ret) + return ERR_PTR(ret); + uclass_foreach_dev(dev, uc) { + if (dev->driver_data == driver_data) { + struct syscon_uc_info *priv; + int ret; + + ret = device_probe(dev); + if (ret) + return ERR_PTR(ret); + priv = dev_get_uclass_priv(dev); + + return priv->regmap; + } + } + + return ERR_PTR(-ENOENT); +} + +void *syscon_get_first_range(ulong driver_data) +{ + struct regmap *map; + + map = syscon_get_regmap_by_driver_data(driver_data); + if (IS_ERR(map)) + return map; + return regmap_get_range(map, 0); +} + +UCLASS_DRIVER(syscon) = { + .id = UCLASS_SYSCON, + .name = "syscon", + .per_device_auto_alloc_size = sizeof(struct syscon_uc_info), + .pre_probe = syscon_pre_probe, +}; diff --git a/include/dm/uclass-id.h b/include/dm/uclass-id.h index c7310d7..24baa5c 100644 --- a/include/dm/uclass-id.h +++ b/include/dm/uclass-id.h @@ -46,6 +46,7 @@ enum uclass_id { UCLASS_SPI, /* SPI bus */ UCLASS_SPI_FLASH, /* SPI flash */ UCLASS_SPI_GENERIC, /* Generic SPI flash target */ + UCLASS_SYSCON, /* System configuration device */ UCLASS_THERMAL, /* Thermal sensor */ UCLASS_USB, /* USB bus */ UCLASS_USB_DEV_GENERIC, /* USB generic device */ diff --git a/include/syscon.h b/include/syscon.h new file mode 100644 index 0000000..c62ccd6 --- /dev/null +++ b/include/syscon.h @@ -0,0 +1,56 @@ +/* + * Copyright (c) 2015 Google, Inc + * Written by Simon Glass sjg@chromium.org + * + * SPDX-License-Identifier: GPL-2.0+ + */ + +#ifndef __SYSCON_H +#define __SYSCON_H + +/** + * struct syscon_uc_info - Information stored by the syscon UCLASS_UCLASS + * + * @regmap: Register map for this controller + */ +struct syscon_uc_info { + struct regmap *regmap; +}; + +/* So far there are no ops so this is a placeholder */ +struct syscon_ops { +}; + +#define syscon_get_ops(dev) ((struct syscon_ops *)(dev)->driver->ops) + +/** + * syscon_get_regmap() - Get access to a register map + * + * @dev: Device to check (UCLASS_SCON) + * @info: Returns regmap for the device + * @return 0 if OK, -ve on error + */ +struct regmap *syscon_get_regmap(struct udevice *dev); + +/** + * syscon_get_regmap_by_driver_data() - Look up a controller by its ID + * + * Each system controller can be accessed by its driver data, which is + * assumed to be unique through the scope of all system controllers that + * are in use. This function looks up the regmap given this driver data. + * + * @driver_data: Driver data value to look up + * @return register map correponding to @driver_data, or -ve error code + */ +struct regmap *syscon_get_regmap_by_driver_data(ulong driver_data); + +/** + * syscon_get_first_range() - get the first memory range from a syscon regmap + * + * @driver_data: Driver data value to look up + * @return first region of register map correponding to @driver_data, or + * -ve error code + */ +void *syscon_get_first_range(ulong driver_data); + +#endif