From mboxrd@z Thu Jan 1 00:00:00 1970 From: Florian Fainelli Subject: Re: [PATCH v3 1/2] of_net: Implement of_get_nvmem_mac_address helper Date: Tue, 27 Mar 2018 15:50:27 -0700 Message-ID: <8623d20b-5a01-b2bd-39f2-900177f96595@gmail.com> References: <1522144346-32367-1-git-send-email-mike.looijmans@topic.nl> <1522144346-32367-2-git-send-email-mike.looijmans@topic.nl> Mime-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: 7bit Cc: linux-kernel@vger.kernel.org, devicetree@vger.kernel.org, andrew@lunn.ch, robh+dt@kernel.org, frowand.list@gmail.com To: Mike Looijmans , netdev@vger.kernel.org Return-path: In-Reply-To: <1522144346-32367-2-git-send-email-mike.looijmans@topic.nl> Content-Language: en-US Sender: linux-kernel-owner@vger.kernel.org List-Id: netdev.vger.kernel.org On 03/27/2018 02:52 AM, Mike Looijmans wrote: > It's common practice to store MAC addresses for network interfaces into > nvmem devices. However the code to actually do this in the kernel lacks, > so this patch adds of_get_nvmem_mac_address() for drivers to obtain the > address from an nvmem cell provider. > > This is particulary useful on devices where the ethernet interface cannot > be configured by the bootloader, for example because it's in an FPGA. > > Signed-off-by: Mike Looijmans > --- > Documentation/devicetree/bindings/net/ethernet.txt | 2 ++ > drivers/of/of_net.c | 40 ++++++++++++++++++++++ > include/linux/of_net.h | 6 ++++ > 3 files changed, 48 insertions(+) > > diff --git a/Documentation/devicetree/bindings/net/ethernet.txt b/Documentation/devicetree/bindings/net/ethernet.txt > index 2974e63..cfc376b 100644 > --- a/Documentation/devicetree/bindings/net/ethernet.txt > +++ b/Documentation/devicetree/bindings/net/ethernet.txt > @@ -10,6 +10,8 @@ Documentation/devicetree/bindings/phy/phy-bindings.txt. > the boot program; should be used in cases where the MAC address assigned to > the device by the boot program is different from the "local-mac-address" > property; > +- nvmem-cells: phandle, reference to an nvmem node for the MAC address; > +- nvmem-cell-names: string, should be "mac-address" if nvmem is to be used; > - max-speed: number, specifies maximum speed in Mbit/s supported by the device; > - max-frame-size: number, maximum transfer unit (IEEE defined MTU), rather than > the maximum frame size (there's contradiction in the Devicetree > diff --git a/drivers/of/of_net.c b/drivers/of/of_net.c > index d820f3e..1c5d372 100644 > --- a/drivers/of/of_net.c > +++ b/drivers/of/of_net.c > @@ -7,6 +7,7 @@ > */ > #include > #include > +#include > #include > #include > #include > @@ -80,3 +81,42 @@ const void *of_get_mac_address(struct device_node *np) > return of_get_mac_addr(np, "address"); > } > EXPORT_SYMBOL(of_get_mac_address); > + > +/** > + * Obtain the MAC address from an nvmem provider named 'mac-address' through > + * device tree. > + * On success, copies the new address into memory pointed to by addr and > + * returns 0. Returns a negative error code otherwise. > + * @np: Device tree node containing the nvmem-cells phandle > + * @addr: Pointer to receive the MAC address using ether_addr_copy() > + */ > +int of_get_nvmem_mac_address(struct device_node *np, void *addr) > +{ > + struct nvmem_cell *cell; > + const void *mac; > + size_t len; > + int ret; > + > + cell = of_nvmem_cell_get(np, "mac-address"); > + if (IS_ERR(cell)) > + return PTR_ERR(cell); > + > + mac = nvmem_cell_read(cell, &len); > + > + nvmem_cell_put(cell); > + > + if (IS_ERR(mac)) > + return PTR_ERR(mac); > + > + if (len < 6 || !is_valid_ether_addr(mac)) { > + ret = -EINVAL; Just one nit here, can you use ETH_ALEN instead of 6? With that fixed: Reviewed-by: Florian Fainelli -- Florian