diff options
-rw-r--r-- | drivers/nvmem/Kconfig | 1 | ||||
-rw-r--r-- | drivers/nvmem/Makefile | 2 | ||||
-rw-r--r-- | drivers/nvmem/core.c | 170 | ||||
-rw-r--r-- | drivers/nvmem/internals.h | 21 | ||||
-rw-r--r-- | drivers/nvmem/layouts.c | 201 | ||||
-rw-r--r-- | drivers/nvmem/layouts/Kconfig | 8 | ||||
-rw-r--r-- | drivers/nvmem/layouts/onie-tlv.c | 24 | ||||
-rw-r--r-- | drivers/nvmem/layouts/sl28vpd.c | 24 | ||||
-rw-r--r-- | include/linux/nvmem-provider.h | 38 |
9 files changed, 354 insertions, 135 deletions
diff --git a/drivers/nvmem/Kconfig b/drivers/nvmem/Kconfig index 5bc9c4874fe3..283134498fbc 100644 --- a/drivers/nvmem/Kconfig +++ b/drivers/nvmem/Kconfig @@ -1,6 +1,7 @@ # SPDX-License-Identifier: GPL-2.0-only menuconfig NVMEM bool "NVMEM Support" + imply NVMEM_LAYOUTS help Support for NVMEM(Non Volatile Memory) devices like EEPROM, EFUSES... diff --git a/drivers/nvmem/Makefile b/drivers/nvmem/Makefile index 423baf089515..cdd01fbf1313 100644 --- a/drivers/nvmem/Makefile +++ b/drivers/nvmem/Makefile @@ -5,6 +5,8 @@ obj-$(CONFIG_NVMEM) += nvmem_core.o nvmem_core-y := core.o +obj-$(CONFIG_NVMEM_LAYOUTS) += nvmem_layouts.o +nvmem_layouts-y := layouts.o obj-y += layouts/ # Devices diff --git a/drivers/nvmem/core.c b/drivers/nvmem/core.c index a885713d6b4b..4c2154ddf8a7 100644 --- a/drivers/nvmem/core.c +++ b/drivers/nvmem/core.c @@ -55,9 +55,6 @@ static LIST_HEAD(nvmem_lookup_list); static BLOCKING_NOTIFIER_HEAD(nvmem_notifier); -static DEFINE_SPINLOCK(nvmem_layout_lock); -static LIST_HEAD(nvmem_layouts); - static int __nvmem_reg_read(struct nvmem_device *nvmem, unsigned int offset, void *val, size_t bytes) { @@ -740,97 +737,22 @@ static int nvmem_add_cells_from_fixed_layout(struct nvmem_device *nvmem) return err; } -int __nvmem_layout_register(struct nvmem_layout *layout, struct module *owner) +int nvmem_layout_register(struct nvmem_layout *layout) { - layout->owner = owner; - - spin_lock(&nvmem_layout_lock); - list_add(&layout->node, &nvmem_layouts); - spin_unlock(&nvmem_layout_lock); - - blocking_notifier_call_chain(&nvmem_notifier, NVMEM_LAYOUT_ADD, layout); + if (!layout->add_cells) + return -EINVAL; - return 0; + /* Populate the cells */ + return layout->add_cells(&layout->nvmem->dev, layout->nvmem); } -EXPORT_SYMBOL_GPL(__nvmem_layout_register); +EXPORT_SYMBOL_GPL(nvmem_layout_register); void nvmem_layout_unregister(struct nvmem_layout *layout) { - blocking_notifier_call_chain(&nvmem_notifier, NVMEM_LAYOUT_REMOVE, layout); - - spin_lock(&nvmem_layout_lock); - list_del(&layout->node); - spin_unlock(&nvmem_layout_lock); + /* Keep the API even with an empty stub in case we need it later */ } EXPORT_SYMBOL_GPL(nvmem_layout_unregister); -static struct nvmem_layout *nvmem_layout_get(struct nvmem_device *nvmem) -{ - struct device_node *layout_np; - struct nvmem_layout *l, *layout = ERR_PTR(-EPROBE_DEFER); - - layout_np = of_nvmem_layout_get_container(nvmem); - if (!layout_np) - return NULL; - - /* Fixed layouts don't have a matching driver */ - if (of_device_is_compatible(layout_np, "fixed-layout")) { - of_node_put(layout_np); - return NULL; - } - - /* - * In case the nvmem device was built-in while the layout was built as a - * module, we shall manually request the layout driver loading otherwise - * we'll never have any match. - */ - of_request_module(layout_np); - - spin_lock(&nvmem_layout_lock); - - list_for_each_entry(l, &nvmem_layouts, node) { - if (of_match_node(l->of_match_table, layout_np)) { - if (try_module_get(l->owner)) - layout = l; - - break; - } - } - - spin_unlock(&nvmem_layout_lock); - of_node_put(layout_np); - - return layout; -} - -static void nvmem_layout_put(struct nvmem_layout *layout) -{ - if (layout) - module_put(layout->owner); -} - -static int nvmem_add_cells_from_layout(struct nvmem_device *nvmem) -{ - struct nvmem_layout *layout = nvmem->layout; - int ret; - - if (layout && layout->add_cells) { - ret = layout->add_cells(&nvmem->dev, nvmem); - if (ret) - return ret; - } - - return 0; -} - -#if IS_ENABLED(CONFIG_OF) -struct device_node *of_nvmem_layout_get_container(struct nvmem_device *nvmem) -{ - return of_get_child_by_name(nvmem->dev.of_node, "nvmem-layout"); -} -EXPORT_SYMBOL_GPL(of_nvmem_layout_get_container); -#endif - const void *nvmem_layout_get_match_data(struct nvmem_device *nvmem, struct nvmem_layout *layout) { @@ -838,7 +760,7 @@ const void *nvmem_layout_get_match_data(struct nvmem_device *nvmem, const struct of_device_id *match; layout_np = of_nvmem_layout_get_container(nvmem); - match = of_match_node(layout->of_match_table, layout_np); + match = of_match_node(layout->dev.driver->of_match_table, layout_np); return match ? match->data : NULL; } @@ -950,19 +872,6 @@ struct nvmem_device *nvmem_register(const struct nvmem_config *config) goto err_put_device; } - /* - * If the driver supplied a layout by config->layout, the module - * pointer will be NULL and nvmem_layout_put() will be a noop. - */ - nvmem->layout = config->layout ?: nvmem_layout_get(nvmem); - if (IS_ERR(nvmem->layout)) { - rval = PTR_ERR(nvmem->layout); - nvmem->layout = NULL; - - if (rval == -EPROBE_DEFER) - goto err_teardown_compat; - } - if (config->cells) { rval = nvmem_add_cells(nvmem, config->cells, config->ncells); if (rval) @@ -983,24 +892,24 @@ struct nvmem_device *nvmem_register(const struct nvmem_config *config) if (rval) goto err_remove_cells; - rval = nvmem_add_cells_from_layout(nvmem); - if (rval) - goto err_remove_cells; - dev_dbg(&nvmem->dev, "Registering nvmem device %s\n", config->name); rval = device_add(&nvmem->dev); if (rval) goto err_remove_cells; + rval = nvmem_populate_layout(nvmem); + if (rval) + goto err_remove_dev; + blocking_notifier_call_chain(&nvmem_notifier, NVMEM_ADD, nvmem); return nvmem; +err_remove_dev: + device_del(&nvmem->dev); err_remove_cells: nvmem_device_remove_all_cells(nvmem); - nvmem_layout_put(nvmem->layout); -err_teardown_compat: if (config->compat) nvmem_sysfs_remove_compat(nvmem, config); err_put_device: @@ -1022,7 +931,7 @@ static void nvmem_device_release(struct kref *kref) device_remove_bin_file(nvmem->base_dev, &nvmem->eeprom); nvmem_device_remove_all_cells(nvmem); - nvmem_layout_put(nvmem->layout); + nvmem_destroy_layout(nvmem); device_unregister(&nvmem->dev); } @@ -1324,6 +1233,12 @@ nvmem_cell_get_from_lookup(struct device *dev, const char *con_id) return cell; } +static void nvmem_layout_module_put(struct nvmem_device *nvmem) +{ + if (nvmem->layout && nvmem->layout->dev.driver) + module_put(nvmem->layout->dev.driver->owner); +} + #if IS_ENABLED(CONFIG_OF) static struct nvmem_cell_entry * nvmem_find_cell_entry_by_node(struct nvmem_device *nvmem, struct device_node *np) @@ -1342,6 +1257,18 @@ nvmem_find_cell_entry_by_node(struct nvmem_device *nvmem, struct device_node *np return cell; } +static int nvmem_layout_module_get_optional(struct nvmem_device *nvmem) +{ + if (!nvmem->layout) + return 0; + + if (!nvmem->layout->dev.driver || + !try_module_get(nvmem->layout->dev.driver->owner)) + return -EPROBE_DEFER; + + return 0; +} + /** * of_nvmem_cell_get() - Get a nvmem cell from given device node and cell id * @@ -1404,16 +1331,29 @@ struct nvmem_cell *of_nvmem_cell_get(struct device_node *np, const char *id) return ERR_CAST(nvmem); } + ret = nvmem_layout_module_get_optional(nvmem); + if (ret) { + of_node_put(cell_np); + __nvmem_device_put(nvmem); + return ERR_PTR(ret); + } + cell_entry = nvmem_find_cell_entry_by_node(nvmem, cell_np); of_node_put(cell_np); if (!cell_entry) { __nvmem_device_put(nvmem); - return ERR_PTR(-ENOENT); + nvmem_layout_module_put(nvmem); + if (nvmem->layout) + return ERR_PTR(-EPROBE_DEFER); + else + return ERR_PTR(-ENOENT); } cell = nvmem_create_cell(cell_entry, id, cell_index); - if (IS_ERR(cell)) + if (IS_ERR(cell)) { __nvmem_device_put(nvmem); + nvmem_layout_module_put(nvmem); + } return cell; } @@ -1527,6 +1467,7 @@ void nvmem_cell_put(struct nvmem_cell *cell) kfree(cell); __nvmem_device_put(nvmem); + nvmem_layout_module_put(nvmem); } EXPORT_SYMBOL_GPL(nvmem_cell_put); @@ -2104,11 +2045,22 @@ EXPORT_SYMBOL_GPL(nvmem_dev_name); static int __init nvmem_init(void) { - return bus_register(&nvmem_bus_type); + int ret; + + ret = bus_register(&nvmem_bus_type); + if (ret) + return ret; + + ret = nvmem_layout_bus_register(); + if (ret) + bus_unregister(&nvmem_bus_type); + + return ret; } static void __exit nvmem_exit(void) { + nvmem_layout_bus_unregister(); bus_unregister(&nvmem_bus_type); } diff --git a/drivers/nvmem/internals.h b/drivers/nvmem/internals.h index 893553fbdf51..4946456c76c7 100644 --- a/drivers/nvmem/internals.h +++ b/drivers/nvmem/internals.h @@ -34,4 +34,25 @@ struct nvmem_device { void *priv; }; +#if IS_ENABLED(CONFIG_OF) +int nvmem_layout_bus_register(void); +void nvmem_layout_bus_unregister(void); +int nvmem_populate_layout(struct nvmem_device *nvmem); +void nvmem_destroy_layout(struct nvmem_device *nvmem); +#else /* CONFIG_OF */ +static inline int nvmem_layout_bus_register(void) +{ + return 0; +} + +static inline void nvmem_layout_bus_unregister(void) {} + +static inline int nvmem_populate_layout(struct nvmem_device *nvmem) +{ + return 0; +} + +static inline void nvmem_destroy_layout(struct nvmem_device *nvmem) { } +#endif /* CONFIG_OF */ + #endif /* ifndef _LINUX_NVMEM_INTERNALS_H */ diff --git a/drivers/nvmem/layouts.c b/drivers/nvmem/layouts.c new file mode 100644 index 000000000000..6a6aa58369ff --- /dev/null +++ b/drivers/nvmem/layouts.c @@ -0,0 +1,201 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * NVMEM layout bus handling + * + * Copyright (C) 2023 Bootlin + * Author: Miquel Raynal <miquel.raynal@bootlin.com + */ + +#include <linux/device.h> +#include <linux/dma-mapping.h> +#include <linux/nvmem-consumer.h> +#include <linux/nvmem-provider.h> +#include <linux/of.h> +#include <linux/of_device.h> +#include <linux/of_irq.h> + +#include "internals.h" + +#define to_nvmem_layout_driver(drv) \ + (container_of((drv), struct nvmem_layout_driver, driver)) +#define to_nvmem_layout_device(_dev) \ + container_of((_dev), struct nvmem_layout, dev) + +static int nvmem_layout_bus_match(struct device *dev, struct device_driver *drv) +{ + return of_driver_match_device(dev, drv); +} + +static int nvmem_layout_bus_probe(struct device *dev) +{ + struct nvmem_layout_driver *drv = to_nvmem_layout_driver(dev->driver); + struct nvmem_layout *layout = to_nvmem_layout_device(dev); + + if (!drv->probe || !drv->remove) + return -EINVAL; + + return drv->probe(layout); +} + +static void nvmem_layout_bus_remove(struct device *dev) +{ + struct nvmem_layout_driver *drv = to_nvmem_layout_driver(dev->driver); + struct nvmem_layout *layout = to_nvmem_layout_device(dev); + + return drv->remove(layout); +} + +static struct bus_type nvmem_layout_bus_type = { + .name = "nvmem-layout", + .match = nvmem_layout_bus_match, + .probe = nvmem_layout_bus_probe, + .remove = nvmem_layout_bus_remove, +}; + +int nvmem_layout_driver_register(struct nvmem_layout_driver *drv) +{ + drv->driver.bus = &nvmem_layout_bus_type; + + return driver_register(&drv->driver); +} +EXPORT_SYMBOL_GPL(nvmem_layout_driver_register); + +void nvmem_layout_driver_unregister(struct nvmem_layout_driver *drv) +{ + driver_unregister(&drv->driver); +} +EXPORT_SYMBOL_GPL(nvmem_layout_driver_unregister); + +static void nvmem_layout_release_device(struct device *dev) +{ + struct nvmem_layout *layout = to_nvmem_layout_device(dev); + + of_node_put(layout->dev.of_node); + kfree(layout); +} + +static int nvmem_layout_create_device(struct nvmem_device *nvmem, + struct device_node *np) +{ + struct nvmem_layout *layout; + struct device *dev; + int ret; + + layout = kzalloc(sizeof(*layout), GFP_KERNEL); + if (!layout) + return -ENOMEM; + + /* Create a bidirectional link */ + layout->nvmem = nvmem; + nvmem->layout = layout; + + /* Device model registration */ + dev = &layout->dev; + device_initialize(dev); + dev->parent = &nvmem->dev; + dev->bus = &nvmem_layout_bus_type; + dev->release = nvmem_layout_release_device; + dev->coherent_dma_mask = DMA_BIT_MASK(32); + dev->dma_mask = &dev->coherent_dma_mask; + device_set_node(dev, of_fwnode_handle(of_node_get(np))); + of_device_make_bus_id(dev); + of_msi_configure(dev, dev->of_node); + + ret = device_add(dev); + if (ret) { + put_device(dev); + return ret; + } + + return 0; +} + +static const struct of_device_id of_nvmem_layout_skip_table[] = { + { .compatible = "fixed-layout", }, + {} +}; + +static int nvmem_layout_bus_populate(struct nvmem_device *nvmem, + struct device_node *layout_dn) +{ + int ret; + + /* Make sure it has a compatible property */ + if (!of_get_property(layout_dn, "compatible", NULL)) { + pr_debug("%s() - skipping %pOF, no compatible prop\n", + __func__, layout_dn); + return 0; + } + + /* Fixed layouts are parsed manually somewhere else for now */ + if (of_match_node(of_nvmem_layout_skip_table, layout_dn)) { + pr_debug("%s() - skipping %pOF node\n", __func__, layout_dn); + return 0; + } + + if (of_node_check_flag(layout_dn, OF_POPULATED_BUS)) { + pr_debug("%s() - skipping %pOF, already populated\n", + __func__, layout_dn); + + return 0; + } + + /* NVMEM layout buses expect only a single device representing the layout */ + ret = nvmem_layout_create_device(nvmem, layout_dn); + if (ret) + return ret; + + of_node_set_flag(layout_dn, OF_POPULATED_BUS); + + return 0; +} + +struct device_node *of_nvmem_layout_get_container(struct nvmem_device *nvmem) +{ + return of_get_child_by_name(nvmem->dev.of_node, "nvmem-layout"); +} +EXPORT_SYMBOL_GPL(of_nvmem_layout_get_container); + +/* + * Returns the number of devices populated, 0 if the operation was not relevant + * for this nvmem device, an error code otherwise. + */ +int nvmem_populate_layout(struct nvmem_device *nvmem) +{ + struct device_node *layout_dn; + int ret; + + layout_dn = of_nvmem_layout_get_container(nvmem); + if (!layout_dn) + return 0; + + /* Populate the layout device */ + device_links_supplier_sync_state_pause(); + ret = nvmem_layout_bus_populate(nvmem, layout_dn); + device_links_supplier_sync_state_resume(); + + of_node_put(layout_dn); + return ret; +} + +void nvmem_destroy_layout(struct nvmem_device *nvmem) +{ + struct device *dev; + + if (!nvmem->layout) + return; + + dev = &nvmem->layout->dev; + of_node_clear_flag(dev->of_node, OF_POPULATED_BUS); + device_unregister(dev); +} + +int nvmem_layout_bus_register(void) +{ + return bus_register(&nvmem_layout_bus_type); +} + +void nvmem_layout_bus_unregister(void) +{ + bus_unregister(&nvmem_layout_bus_type); +} diff --git a/drivers/nvmem/layouts/Kconfig b/drivers/nvmem/layouts/Kconfig index 7ff1ee1c1f05..9c6e672fc350 100644 --- a/drivers/nvmem/layouts/Kconfig +++ b/drivers/nvmem/layouts/Kconfig @@ -1,5 +1,11 @@ # SPDX-License-Identifier: GPL-2.0 +config NVMEM_LAYOUTS + bool + depends on OF + +if NVMEM_LAYOUTS + menu "Layout Types" config NVMEM_LAYOUT_SL28_VPD @@ -21,3 +27,5 @@ config NVMEM_LAYOUT_ONIE_TLV If unsure, say N. endmenu + +endif diff --git a/drivers/nvmem/layouts/onie-tlv.c b/drivers/nvmem/layouts/onie-tlv.c index defd42d4375c..b24cc5dcc6ee 100644 --- a/drivers/nvmem/layouts/onie-tlv.c +++ b/drivers/nvmem/layouts/onie-tlv.c @@ -225,16 +225,32 @@ static int onie_tlv_parse_table(struct device *dev, struct nvmem_device *nvmem) return 0; } +static int onie_tlv_probe(struct nvmem_layout *layout) +{ + layout->add_cells = onie_tlv_parse_table; + + return nvmem_layout_register(layout); +} + +static void onie_tlv_remove(struct nvmem_layout *layout) +{ + nvmem_layout_unregister(layout); +} + static const struct of_device_id onie_tlv_of_match_table[] = { { .compatible = "onie,tlv-layout", }, {}, }; MODULE_DEVICE_TABLE(of, onie_tlv_of_match_table); -static struct nvmem_layout onie_tlv_layout = { - .name = "ONIE tlv layout", - .of_match_table = onie_tlv_of_match_table, - .add_cells = onie_tlv_parse_table, +static struct nvmem_layout_driver onie_tlv_layout = { + .driver = { + .owner = THIS_MODULE, + .name = "onie-tlv-layout", + .of_match_table = onie_tlv_of_match_table, + }, + .probe = onie_tlv_probe, + .remove = onie_tlv_remove, }; module_nvmem_layout_driver(onie_tlv_layout); diff --git a/drivers/nvmem/layouts/sl28vpd.c b/drivers/nvmem/layouts/sl28vpd.c index 26c7cf21b523..b8ffae646cc2 100644 --- a/drivers/nvmem/layouts/sl28vpd.c +++ b/drivers/nvmem/layouts/sl28vpd.c @@ -134,16 +134,32 @@ static int sl28vpd_add_cells(struct device *dev, struct nvmem_device *nvmem) return 0; } +static int sl28vpd_probe(struct nvmem_layout *layout) +{ + layout->add_cells = sl28vpd_add_cells; + + return nvmem_layout_register(layout); +} + +static void sl28vpd_remove(struct nvmem_layout *layout) +{ + nvmem_layout_unregister(layout); +} + static const struct of_device_id sl28vpd_of_match_table[] = { { .compatible = "kontron,sl28-vpd" }, {}, }; MODULE_DEVICE_TABLE(of, sl28vpd_of_match_table); -static struct nvmem_layout sl28vpd_layout = { - .name = "sl28-vpd", - .of_match_table = sl28vpd_of_match_table, - .add_cells = sl28vpd_add_cells, +static struct nvmem_layout_driver sl28vpd_layout = { + .driver = { + .owner = THIS_MODULE, + .name = "kontron-sl28vpd-layout", + .of_match_table = sl28vpd_of_match_table, + }, + .probe = sl28vpd_probe, + .remove = sl28vpd_remove, }; module_nvmem_layout_driver(sl28vpd_layout); diff --git a/include/linux/nvmem-provider.h b/include/linux/nvmem-provider.h index 36415a602d9e..6fe65b35ea97 100644 --- a/include/linux/nvmem-provider.h +++ b/include/linux/nvmem-provider.h @@ -9,6 +9,7 @@ #ifndef _LINUX_NVMEM_PROVIDER_H #define _LINUX_NVMEM_PROVIDER_H +#include <linux/device.h> #include <linux/device/driver.h> #include <linux/err.h> #include <linux/errno.h> @@ -158,12 +159,11 @@ struct nvmem_cell_table { /** * struct nvmem_layout - NVMEM layout definitions * - * @name: Layout name. - * @of_match_table: Open firmware match table. - * @add_cells: Called to populate the layout using - * nvmem_add_one_cell(). - * @owner: Pointer to struct module. - * @node: List node. + * @dev: Device-model layout device. + * @nvmem: The underlying NVMEM device + * @add_cells: Will be called if a nvmem device is found which + * has this layout. The function will add layout + * specific cells with nvmem_add_one_cell(). * * A nvmem device can hold a well defined structure which can just be * evaluated during runtime. For example a TLV list, or a list of "name=val" @@ -171,13 +171,15 @@ struct nvmem_cell_table { * cells. */ struct nvmem_layout { - const char *name; - const struct of_device_id *of_match_table; + struct device dev; + struct nvmem_device *nvmem; int (*add_cells)(struct device *dev, struct nvmem_device *nvmem); +}; - /* private */ - struct module *owner; - struct list_head node; +struct nvmem_layout_driver { + struct device_driver driver; + int (*probe)(struct nvmem_layout *layout); + void (*remove)(struct nvmem_layout *layout); }; #if IS_ENABLED(CONFIG_NVMEM) @@ -194,11 +196,15 @@ void nvmem_del_cell_table(struct nvmem_cell_table *table); int nvmem_add_one_cell(struct nvmem_device *nvmem, const struct nvmem_cell_info *info); -int __nvmem_layout_register(struct nvmem_layout *layout, struct module *owner); -#define nvmem_layout_register(layout) \ - __nvmem_layout_register(layout, THIS_MODULE) +int nvmem_layout_register(struct nvmem_layout *layout); void nvmem_layout_unregister(struct nvmem_layout *layout); +int nvmem_layout_driver_register(struct nvmem_layout_driver *drv); +void nvmem_layout_driver_unregister(struct nvmem_layout_driver *drv); +#define module_nvmem_layout_driver(__nvmem_layout_driver) \ + module_driver(__nvmem_layout_driver, nvmem_layout_driver_register, \ + nvmem_layout_driver_unregister) + const void *nvmem_layout_get_match_data(struct nvmem_device *nvmem, struct nvmem_layout *layout); @@ -262,8 +268,4 @@ static inline struct device_node *of_nvmem_layout_get_container(struct nvmem_dev #endif /* CONFIG_NVMEM && CONFIG_OF */ -#define module_nvmem_layout_driver(__layout_driver) \ - module_driver(__layout_driver, nvmem_layout_register, \ - nvmem_layout_unregister) - #endif /* ifndef _LINUX_NVMEM_PROVIDER_H */ |