From mboxrd@z Thu Jan 1 00:00:00 1970 From: Lee Jones Subject: Re: [PATCH v4 1/3] mfd: add support for Diolan DLN-2 devices Date: Wed, 17 Sep 2014 08:56:15 -0700 Message-ID: <20140917155615.GG30918@lee--X1> References: <1410290686-6680-1-git-send-email-octavian.purdila@intel.com> <1410290686-6680-2-git-send-email-octavian.purdila@intel.com> <20140916232149.GB30918@lee--X1> Mime-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: QUOTED-PRINTABLE Return-path: Content-Disposition: inline In-Reply-To: Sender: linux-kernel-owner@vger.kernel.org To: Octavian Purdila Cc: Greg Kroah-Hartman , Linus Walleij , Alexandre Courbot , wsa@the-dreams.de, Samuel Ortiz , Arnd Bergmann , Johan Hovold , Daniel Baluta , Laurentiu Palcu , linux-usb@vger.kernel.org, lkml , linux-gpio@vger.kernel.org, linux-i2c@vger.kernel.org List-Id: linux-gpio@vger.kernel.org On Wed, 17 Sep 2014, Octavian Purdila wrote: > On Wed, Sep 17, 2014 at 2:21 AM, Lee Jones wro= te: > > > > On Tue, 09 Sep 2014, Octavian Purdila wrote: > > > > > This patch implements the USB part of the Diolan USB-I2C/SPI/GPIO > > > Master Adapter DLN-2. Details about the device can be found here: > > > > > > https://www.diolan.com/i2c/i2c_interface.html. > > > > > > Information about the USB protocol can be found in the Programmer= 's > > > Reference Manual [1], see section 1.7. > > > > > > Because the hardware has a single transmit endpoint and a single > > > receive endpoint the communication between the various DLN2 drive= rs > > > and the hardware will be muxed/demuxed by this driver. > > > > > > Each DLN2 module will be identified by the handle field within th= e DLN2 > > > message header. If a DLN2 module issues multiple commands in para= llel > > > they will be identified by the echo counter field in the message = header. > > > > > > The DLN2 modules can use the dln2_transfer() function to issue a > > > command and wait for its response. They can also register a callb= ack > > > that is going to be called when a specific event id is generated = by > > > the device (e.g. GPIO interrupts). The device uses handle 0 for > > > sending events. > > > > > > [1] https://www.diolan.com/downloads/dln-api-manual.pdf > > > > > > Signed-off-by: Octavian Purdila > > > --- > > > drivers/mfd/Kconfig | 9 + > > > drivers/mfd/Makefile | 1 + > > > drivers/mfd/dln2.c | 681 +++++++++++++++++++++++++++++++++= ++++++++++++++ > > > include/linux/mfd/dln2.h | 71 +++++ > > > 4 files changed, 762 insertions(+) > > > create mode 100644 drivers/mfd/dln2.c > > > create mode 100644 include/linux/mfd/dln2.h [...] > > > diff --git a/include/linux/mfd/dln2.h b/include/linux/mfd/dln2.h > > > new file mode 100644 > > > index 0000000..197565d > > > --- /dev/null > > > +++ b/include/linux/mfd/dln2.h > > > @@ -0,0 +1,71 @@ > > > +#ifndef __LINUX_USB_DLN2_H > > > +#define __LINUX_USB_DLN2_H > > > + > > > +#define DLN2_CMD(cmd, id) ((cmd) | ((id) << 8)) > > > + > > > +struct dln2_platform_data { > > > + u16 handle; > > > + union { > > > + struct { > > > + u8 port; > > > + } i2c; > > > + }; > > > +}; > > > > Why this complexity? >=20 > There is also an SPI interface on this adapter which will probably th= e > port information and maybe some additional information. Would you > prefer to add the union later, when we add the SPI driver? Yes please. --=20 Lee Jones Linaro STMicroelectronics Landing Team Lead Linaro.org =E2=94=82 Open source software for ARM SoCs =46ollow Linaro: Facebook | Twitter | Blog