diff options
Diffstat (limited to 'target/linux/ipq806x/patches-4.4/019-4-nvmem-Add-backwards-compatibility-support-for-older-EEPROM-drivers.patch')
| -rw-r--r-- | target/linux/ipq806x/patches-4.4/019-4-nvmem-Add-backwards-compatibility-support-for-older-EEPROM-drivers.patch | 181 |
1 files changed, 181 insertions, 0 deletions
diff --git a/target/linux/ipq806x/patches-4.4/019-4-nvmem-Add-backwards-compatibility-support-for-older-EEPROM-drivers.patch b/target/linux/ipq806x/patches-4.4/019-4-nvmem-Add-backwards-compatibility-support-for-older-EEPROM-drivers.patch new file mode 100644 index 0000000000..6344d0ed03 --- /dev/null +++ b/target/linux/ipq806x/patches-4.4/019-4-nvmem-Add-backwards-compatibility-support-for-older-EEPROM-drivers.patch @@ -0,0 +1,181 @@ +From b6c217ab9be6895384cf0b284ace84ad79e5c53b Mon Sep 17 00:00:00 2001 +From: Andrew Lunn <andrew@lunn.ch> +Date: Fri, 26 Feb 2016 20:59:19 +0100 +Subject: nvmem: Add backwards compatibility support for older EEPROM drivers. + +Older drivers made an 'eeprom' file available in the /sys device +directory. Have the NVMEM core provide this to retain backwards +compatibility. + +Signed-off-by: Andrew Lunn <andrew@lunn.ch> +Acked-by: Srinivas Kandagatla <srinivas.kandagatla@linaro.org> +Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> +--- + drivers/nvmem/core.c | 84 ++++++++++++++++++++++++++++++++++++++---- + include/linux/nvmem-provider.h | 4 +- + 2 files changed, 79 insertions(+), 9 deletions(-) + +--- a/drivers/nvmem/core.c ++++ b/drivers/nvmem/core.c +@@ -38,8 +38,13 @@ struct nvmem_device { + int users; + size_t size; + bool read_only; ++ int flags; ++ struct bin_attribute eeprom; ++ struct device *base_dev; + }; + ++#define FLAG_COMPAT BIT(0) ++ + struct nvmem_cell { + const char *name; + int offset; +@@ -56,16 +61,26 @@ static DEFINE_IDA(nvmem_ida); + static LIST_HEAD(nvmem_cells); + static DEFINE_MUTEX(nvmem_cells_mutex); + ++#ifdef CONFIG_DEBUG_LOCK_ALLOC ++static struct lock_class_key eeprom_lock_key; ++#endif ++ + #define to_nvmem_device(d) container_of(d, struct nvmem_device, dev) + + static ssize_t bin_attr_nvmem_read(struct file *filp, struct kobject *kobj, + struct bin_attribute *attr, + char *buf, loff_t pos, size_t count) + { +- struct device *dev = container_of(kobj, struct device, kobj); +- struct nvmem_device *nvmem = to_nvmem_device(dev); ++ struct device *dev; ++ struct nvmem_device *nvmem; + int rc; + ++ if (attr->private) ++ dev = attr->private; ++ else ++ dev = container_of(kobj, struct device, kobj); ++ nvmem = to_nvmem_device(dev); ++ + /* Stop the user from reading */ + if (pos >= nvmem->size) + return 0; +@@ -90,10 +105,16 @@ static ssize_t bin_attr_nvmem_write(stru + struct bin_attribute *attr, + char *buf, loff_t pos, size_t count) + { +- struct device *dev = container_of(kobj, struct device, kobj); +- struct nvmem_device *nvmem = to_nvmem_device(dev); ++ struct device *dev; ++ struct nvmem_device *nvmem; + int rc; + ++ if (attr->private) ++ dev = attr->private; ++ else ++ dev = container_of(kobj, struct device, kobj); ++ nvmem = to_nvmem_device(dev); ++ + /* Stop the user from writing */ + if (pos >= nvmem->size) + return 0; +@@ -349,6 +370,43 @@ err: + return rval; + } + ++/* ++ * nvmem_setup_compat() - Create an additional binary entry in ++ * drivers sys directory, to be backwards compatible with the older ++ * drivers/misc/eeprom drivers. ++ */ ++static int nvmem_setup_compat(struct nvmem_device *nvmem, ++ const struct nvmem_config *config) ++{ ++ int rval; ++ ++ if (!config->base_dev) ++ return -EINVAL; ++ ++ if (nvmem->read_only) ++ nvmem->eeprom = bin_attr_ro_root_nvmem; ++ else ++ nvmem->eeprom = bin_attr_rw_root_nvmem; ++ nvmem->eeprom.attr.name = "eeprom"; ++ nvmem->eeprom.size = nvmem->size; ++#ifdef CONFIG_DEBUG_LOCK_ALLOC ++ nvmem->eeprom.attr.key = &eeprom_lock_key; ++#endif ++ nvmem->eeprom.private = &nvmem->dev; ++ nvmem->base_dev = config->base_dev; ++ ++ rval = device_create_bin_file(nvmem->base_dev, &nvmem->eeprom); ++ if (rval) { ++ dev_err(&nvmem->dev, ++ "Failed to create eeprom binary file %d\n", rval); ++ return rval; ++ } ++ ++ nvmem->flags |= FLAG_COMPAT; ++ ++ return 0; ++} ++ + /** + * nvmem_register() - Register a nvmem device for given nvmem_config. + * Also creates an binary entry in /sys/bus/nvmem/devices/dev-name/nvmem +@@ -416,16 +474,23 @@ struct nvmem_device *nvmem_register(cons + dev_dbg(&nvmem->dev, "Registering nvmem device %s\n", config->name); + + rval = device_add(&nvmem->dev); +- if (rval) { +- ida_simple_remove(&nvmem_ida, nvmem->id); +- kfree(nvmem); +- return ERR_PTR(rval); ++ if (rval) ++ goto out; ++ ++ if (config->compat) { ++ rval = nvmem_setup_compat(nvmem, config); ++ if (rval) ++ goto out; + } + + if (config->cells) + nvmem_add_cells(nvmem, config); + + return nvmem; ++out: ++ ida_simple_remove(&nvmem_ida, nvmem->id); ++ kfree(nvmem); ++ return ERR_PTR(rval); + } + EXPORT_SYMBOL_GPL(nvmem_register); + +@@ -445,6 +510,9 @@ int nvmem_unregister(struct nvmem_device + } + mutex_unlock(&nvmem_mutex); + ++ if (nvmem->flags & FLAG_COMPAT) ++ device_remove_bin_file(nvmem->base_dev, &nvmem->eeprom); ++ + nvmem_device_remove_all_cells(nvmem); + device_del(&nvmem->dev); + +--- a/include/linux/nvmem-provider.h ++++ b/include/linux/nvmem-provider.h +@@ -24,6 +24,9 @@ struct nvmem_config { + int ncells; + bool read_only; + bool root_only; ++ /* To be only used by old driver/misc/eeprom drivers */ ++ bool compat; ++ struct device *base_dev; + }; + + #if IS_ENABLED(CONFIG_NVMEM) +@@ -44,5 +47,4 @@ static inline int nvmem_unregister(struc + } + + #endif /* CONFIG_NVMEM */ +- + #endif /* ifndef _LINUX_NVMEM_PROVIDER_H */ |