Message ID | 20200321202443.15352-2-tobias@waldekranz.com |
---|---|
State | Superseded |
Delegated to: | David Miller |
Headers | show |
Series | [v3,1/2] dt-bindings: net: add marvell usb to mdio bindings | expand |
On Sat, Mar 21, 2020 at 09:24:43PM +0100, Tobias Waldekranz wrote: > An MDIO controller present on development boards for Marvell switches > from the Link Street (88E6xxx) family. > > Using this module, you can use the following setup as a development > platform for switchdev and DSA related work. > > .-------. .-----------------. > | USB----USB | > | SoC | | 88E6390X-DB ETH1-10 > | ETH----ETH0 | > '-------' '-----------------' > > Signed-off-by: Tobias Waldekranz <tobias@waldekranz.com> > --- > > Hi linux-usb, > > This is my first ever USB driver, therefore I would really appreciate > it if someone could have a look at it from a USB perspective before it > is (hopefully) pulled into net-next. From a USB point of view, it looks sane, only one question: > +static int mvusb_mdio_probe(struct usb_interface *interface, > + const struct usb_device_id *id) > +{ > + struct device *dev = &interface->dev; > + struct mvusb_mdio *mvusb; > + struct mii_bus *mdio; > + > + mdio = devm_mdiobus_alloc_size(dev, sizeof(*mvusb)); You allocate a bigger buffer here than the original pointer thinks it is pointing to? > + if (!mdio) > + return -ENOMEM; > + > + mvusb = mdio->priv; And then you set this pointer here? If that's the way this is supposed to work, that's fine, just feels like the math is wrong somewhere... thanks, greg k-h
On Sun Mar 22, 2020 at 8:40 AM, Greg KH wrote: > From a USB point of view, it looks sane, only one question: Great, thanks for the review. > > +static int mvusb_mdio_probe(struct usb_interface *interface, > > + const struct usb_device_id *id) > > +{ > > + struct device *dev = &interface->dev; > > + struct mvusb_mdio *mvusb; > > + struct mii_bus *mdio; > > + > > + mdio = devm_mdiobus_alloc_size(dev, sizeof(*mvusb)); > > > You allocate a bigger buffer here than the original pointer thinks it is > pointing to? Yes. I've seen this pattern in a couple of places in the kernel, e.g. alloc_netdev also does this. The object is extended with the requested size, and the offset is stored somewhere for later use by the driver. > > + if (!mdio) > > + return -ENOMEM; > > + > > + mvusb = mdio->priv; > > > And then you set this pointer here? ...in this case in the priv member. https://code.woboq.org/linux/linux/drivers/net/phy/mdio_bus.c.html#143 Thanks
On Sun, Mar 22, 2020 at 10:09:28AM +0100, Tobias Waldekranz wrote: > On Sun Mar 22, 2020 at 8:40 AM, Greg KH wrote: > > From a USB point of view, it looks sane, only one question: > > Great, thanks for the review. > > > > +static int mvusb_mdio_probe(struct usb_interface *interface, > > > + const struct usb_device_id *id) > > > +{ > > > + struct device *dev = &interface->dev; > > > + struct mvusb_mdio *mvusb; > > > + struct mii_bus *mdio; > > > + > > > + mdio = devm_mdiobus_alloc_size(dev, sizeof(*mvusb)); > > > > > > You allocate a bigger buffer here than the original pointer thinks it is > > pointing to? > > Yes. I've seen this pattern in a couple of places in the kernel, > e.g. alloc_netdev also does this. The object is extended with the > requested size, and the offset is stored somewhere for later use by > the driver. > > > > + if (!mdio) > > > + return -ENOMEM; > > > + > > > + mvusb = mdio->priv; > > > > > > And then you set this pointer here? > > ...in this case in the priv member. > > https://code.woboq.org/linux/linux/drivers/net/phy/mdio_bus.c.html#143 Ok, just wanted to make sure :) Reviewed-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
On Sat, Mar 21, 2020 at 09:24:43PM +0100, Tobias Waldekranz wrote: > An MDIO controller present on development boards for Marvell switches > from the Link Street (88E6xxx) family. > > Using this module, you can use the following setup as a development > platform for switchdev and DSA related work. > > .-------. .-----------------. > | USB----USB | > | SoC | | 88E6390X-DB ETH1-10 > | ETH----ETH0 | > '-------' '-----------------' > > Signed-off-by: Tobias Waldekranz <tobias@waldekranz.com> Reviewed-by: Andrew Lunn <andrew@lunn.ch> Andrew
Hi Tobias, On 3/21/2020 1:24 PM, Tobias Waldekranz wrote: > An MDIO controller present on development boards for Marvell switches > from the Link Street (88E6xxx) family. > > Using this module, you can use the following setup as a development > platform for switchdev and DSA related work. > > .-------. .-----------------. > | USB----USB | > | SoC | | 88E6390X-DB ETH1-10 > | ETH----ETH0 | > '-------' '-----------------' > > Signed-off-by: Tobias Waldekranz <tobias@waldekranz.com> > --- [snip] > +config MDIO_MVUSB > + tristate "Marvell USB to MDIO Adapter" > + depends on OF_MDIO && USB You could drop OF_MDIO here since of_mdiobus_register() does default to mdiobus_register() when CONFIG_OF is disabled. Other than that, LGTM! Reviewed-by: Florian Fainelli <f.fainelli@gmail.com>
diff --git a/MAINTAINERS b/MAINTAINERS index ff35669f8712..f36023d4ee44 100644 --- a/MAINTAINERS +++ b/MAINTAINERS @@ -10105,6 +10105,7 @@ MARVELL USB MDIO CONTROLLER DRIVER M: Tobias Waldekranz <tobias@waldekranz.com> L: netdev@vger.kernel.org S: Maintained +F: drivers/net/phy/mdio-mvusb.c F: Documentation/devicetree/bindings/net/marvell,mvusb.yaml MARVELL XENON MMC/SD/SDIO HOST CONTROLLER DRIVER diff --git a/drivers/net/phy/Kconfig b/drivers/net/phy/Kconfig index cc7f1df855da..be9ae8620cd1 100644 --- a/drivers/net/phy/Kconfig +++ b/drivers/net/phy/Kconfig @@ -179,6 +179,13 @@ config MDIO_MSCC_MIIM This driver supports the MIIM (MDIO) interface found in the network switches of the Microsemi SoCs +config MDIO_MVUSB + tristate "Marvell USB to MDIO Adapter" + depends on OF_MDIO && USB + help + A USB to MDIO converter present on development boards for + Marvell's Link Street family of Ethernet switches. + config MDIO_OCTEON tristate "Octeon and some ThunderX SOCs MDIO buses" depends on (64BIT && OF_MDIO) || COMPILE_TEST diff --git a/drivers/net/phy/Makefile b/drivers/net/phy/Makefile index 70774ab474e6..2f5c7093a65b 100644 --- a/drivers/net/phy/Makefile +++ b/drivers/net/phy/Makefile @@ -40,6 +40,7 @@ obj-$(CONFIG_MDIO_I2C) += mdio-i2c.o obj-$(CONFIG_MDIO_IPQ8064) += mdio-ipq8064.o obj-$(CONFIG_MDIO_MOXART) += mdio-moxart.o obj-$(CONFIG_MDIO_MSCC_MIIM) += mdio-mscc-miim.o +obj-$(CONFIG_MDIO_MVUSB) += mdio-mvusb.o obj-$(CONFIG_MDIO_OCTEON) += mdio-octeon.o obj-$(CONFIG_MDIO_SUN4I) += mdio-sun4i.o obj-$(CONFIG_MDIO_THUNDER) += mdio-thunder.o diff --git a/drivers/net/phy/mdio-mvusb.c b/drivers/net/phy/mdio-mvusb.c new file mode 100644 index 000000000000..d5eabddfdf51 --- /dev/null +++ b/drivers/net/phy/mdio-mvusb.c @@ -0,0 +1,120 @@ +// SPDX-License-Identifier: GPL-2.0 + +#include <linux/kernel.h> +#include <linux/module.h> +#include <linux/of_mdio.h> +#include <linux/phy.h> +#include <linux/usb.h> + +#define USB_MARVELL_VID 0x1286 + +static const struct usb_device_id mvusb_mdio_table[] = { + { USB_DEVICE(USB_MARVELL_VID, 0x1fa4) }, + + {} +}; +MODULE_DEVICE_TABLE(usb, mvusb_mdio_table); + +enum { + MVUSB_CMD_PREAMBLE0, + MVUSB_CMD_PREAMBLE1, + MVUSB_CMD_ADDR, + MVUSB_CMD_VAL, +}; + +struct mvusb_mdio { + struct usb_device *udev; + struct mii_bus *mdio; + + __le16 buf[4]; +}; + +static int mvusb_mdio_read(struct mii_bus *mdio, int dev, int reg) +{ + struct mvusb_mdio *mvusb = mdio->priv; + int err, alen; + + if (dev & MII_ADDR_C45) + return -EOPNOTSUPP; + + mvusb->buf[MVUSB_CMD_ADDR] = cpu_to_le16(0xa400 | (dev << 5) | reg); + + err = usb_bulk_msg(mvusb->udev, usb_sndbulkpipe(mvusb->udev, 2), + mvusb->buf, 6, &alen, 100); + if (err) + return err; + + err = usb_bulk_msg(mvusb->udev, usb_rcvbulkpipe(mvusb->udev, 6), + &mvusb->buf[MVUSB_CMD_VAL], 2, &alen, 100); + if (err) + return err; + + return le16_to_cpu(mvusb->buf[MVUSB_CMD_VAL]); +} + +static int mvusb_mdio_write(struct mii_bus *mdio, int dev, int reg, u16 val) +{ + struct mvusb_mdio *mvusb = mdio->priv; + int alen; + + if (dev & MII_ADDR_C45) + return -EOPNOTSUPP; + + mvusb->buf[MVUSB_CMD_ADDR] = cpu_to_le16(0x8000 | (dev << 5) | reg); + mvusb->buf[MVUSB_CMD_VAL] = cpu_to_le16(val); + + return usb_bulk_msg(mvusb->udev, usb_sndbulkpipe(mvusb->udev, 2), + mvusb->buf, 8, &alen, 100); +} + +static int mvusb_mdio_probe(struct usb_interface *interface, + const struct usb_device_id *id) +{ + struct device *dev = &interface->dev; + struct mvusb_mdio *mvusb; + struct mii_bus *mdio; + + mdio = devm_mdiobus_alloc_size(dev, sizeof(*mvusb)); + if (!mdio) + return -ENOMEM; + + mvusb = mdio->priv; + mvusb->mdio = mdio; + mvusb->udev = usb_get_dev(interface_to_usbdev(interface)); + + /* Reversed from USB PCAPs, no idea what these mean. */ + mvusb->buf[MVUSB_CMD_PREAMBLE0] = cpu_to_le16(0xe800); + mvusb->buf[MVUSB_CMD_PREAMBLE1] = cpu_to_le16(0x0001); + + snprintf(mdio->id, MII_BUS_ID_SIZE, "mvusb-%s", dev_name(dev)); + mdio->name = mdio->id; + mdio->parent = dev; + mdio->read = mvusb_mdio_read; + mdio->write = mvusb_mdio_write; + + usb_set_intfdata(interface, mvusb); + return of_mdiobus_register(mdio, dev->of_node); +} + +static void mvusb_mdio_disconnect(struct usb_interface *interface) +{ + struct mvusb_mdio *mvusb = usb_get_intfdata(interface); + struct usb_device *udev = mvusb->udev; + + mdiobus_unregister(mvusb->mdio); + usb_set_intfdata(interface, NULL); + usb_put_dev(udev); +} + +static struct usb_driver mvusb_mdio_driver = { + .name = "mvusb_mdio", + .id_table = mvusb_mdio_table, + .probe = mvusb_mdio_probe, + .disconnect = mvusb_mdio_disconnect, +}; + +module_usb_driver(mvusb_mdio_driver); + +MODULE_AUTHOR("Tobias Waldekranz <tobias@waldekranz.com>"); +MODULE_DESCRIPTION("Marvell USB MDIO Adapter"); +MODULE_LICENSE("GPL");
An MDIO controller present on development boards for Marvell switches from the Link Street (88E6xxx) family. Using this module, you can use the following setup as a development platform for switchdev and DSA related work. .-------. .-----------------. | USB----USB | | SoC | | 88E6390X-DB ETH1-10 | ETH----ETH0 | '-------' '-----------------' Signed-off-by: Tobias Waldekranz <tobias@waldekranz.com> --- Hi linux-usb, This is my first ever USB driver, therefore I would really appreciate it if someone could have a look at it from a USB perspective before it is (hopefully) pulled into net-next. Thanks v2->v3: - Rename driver smi2usb -> mvusb. - Clean up unused USB references. v1->v2: - Reverse christmas tree ordering of local variables. --- MAINTAINERS | 1 + drivers/net/phy/Kconfig | 7 ++ drivers/net/phy/Makefile | 1 + drivers/net/phy/mdio-mvusb.c | 120 +++++++++++++++++++++++++++++++++++ 4 files changed, 129 insertions(+) create mode 100644 drivers/net/phy/mdio-mvusb.c