From mboxrd@z Thu Jan 1 00:00:00 1970 From: Heiko Schocher Date: Wed, 29 Oct 2014 08:31:46 +0100 Subject: [U-Boot] [RFC PATCH 0/12] RFC: dm: Add I2C support In-Reply-To: <20141024150301.GU25506@bill-the-cat> References: <1413178778-30846-1-git-send-email-sjg@chromium.org> <20141024150301.GU25506@bill-the-cat> Message-ID: <545097E2.3090508@denx.de> List-Id: MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit To: u-boot@lists.denx.de Hello Tom, Am 24.10.2014 17:03, schrieb Tom Rini: > On Sun, Oct 12, 2014 at 11:39:26PM -0600, Simon Glass wrote: > >> (Note this is RFC since the uclass interface needs discussion and also >> because only sandbox is implemented so far. But I thought it best to get >> this out there as soon as I wrote it as it may influence the PMIC library, >> etc.) >> >> This series is an initial attempt to add I2C support to driver model. It >> has become apparent that this is a high priority as it is widely used. It >> follows along to some extent from the SPI conversion. >> >> Several changes are made from the original I2C implementations. >> >> Firstly It is not necessary to specify the chip address with every call, >> since each chip knows its own address - it is stored in struct dm_i2c_chip >> which is attached to each chip on the I2C bus. However, this information >> *is* passed to the driver since I presume most drivers need it and it would >> be cumbersome to look up in every call. >> >> Secondly there is no concept of a 'current' I2C bus so all associated logic >> is removed. With driver model i2c_set_bus_num() and i2c_get_bus_num() are >> not available. Since the chip device specifies both the bus and the chip >> address, there is no need for this concept. It also causes problems when >> one driver changes the current bus and forgets to change it back. >> >> Thirdly initialisation is handled by driver model's normal probe() method >> on each device so there should be no need for i2c_init_all(), i2c_init(), >> i2c_init_board(), i2c_board_late_init() and board_i2c_init(). >> >> I2C muxes are not yet supported. To support these we will need to maintain >> state of the current mux settings to avoid resetting every mux every time. >> Probably we need to add a sandbox I2C mux driver to permit testing of this. >> This can probably be done later. >> >> Platform data is not yet supported either, only device tree. The >> U_BOOT_I2C_MKENT_COMPLETE() and U_BOOT_I2C_ADAP_COMPLETE() macros are not >> used. Also struct i2c_adapter is not defined anymore. This will need to be >> addressed, perhaps as part of converting over a board that does not use >> device tree. >> >> This series is available at u-boot-dm/i2c-working. > > Nothing jumped out at me. Heiko? Looking in this patches soon... sorry for the delay. bye, Heiko -- DENX Software Engineering GmbH, MD: Wolfgang Denk & Detlev Zundel HRB 165235 Munich, Office: Kirchenstr.5, D-82194 Groebenzell, Germany