From mboxrd@z Thu Jan 1 00:00:00 1970 From: Andy Shevchenko Subject: Re: [PATCH v5 6/7] i2c: designware: enable SLAVE in platform module Date: Wed, 28 Dec 2016 19:10:43 +0200 Message-ID: <1482945043.9552.174.camel@linux.intel.com> References: <1482939844.9552.165.camel@linux.intel.com> <20e47113-efd7-787c-b2f8-39e9fd8b83d2@synopsys.com> <1482942696.9552.172.camel@linux.intel.com> Mime-Version: 1.0 Content-Type: text/plain; charset="UTF-8" Content-Transfer-Encoding: 8bit Return-path: In-Reply-To: Sender: linux-i2c-owner@vger.kernel.org To: Luis Oliveira , wsa@the-dreams.de, robh+dt@kernel.org, mark.rutland@arm.com, jarkko.nikula@linux.intel.com, mika.westerberg@linux.intel.com, linux-i2c@vger.kernel.org, devicetree@vger.kernel.org, linux-kernel@vger.kernel.org Cc: Ramiro.Oliveira@synopsys.com, Joao.Pinto@synopsys.com, CARLOS.PALMINHA@synopsys.com List-Id: devicetree@vger.kernel.org On Wed, 2016-12-28 at 16:41 +0000, Luis Oliveira wrote: > On 28-Dec-16 16:31, Andy Shevchenko wrote: > > On Wed, 2016-12-28 at 15:53 +0000, Luis Oliveira wrote: > > > On 28-Dec-16 15:44, Andy Shevchenko wrote: > > > > On Wed, 2016-12-28 at 14:43 +0000, Luis Oliveira wrote: > > > > > - Slave mode selected in platform module (devicetree support > > > > > only) > > > > > - Check for ACPI - not supported in SLAVE mode: > > > > >   - Changed the ifndef style to the use of ACPI_HANDLE that > > > > > returns > > > > > NULL > > > > >     if the device was not enumerated from ACPI namespace. > > > > > > > > I'm not sure what is wrong with ACPI? > > > > > > I dont have a way to test it. Just that. > > > > Okay, can you provide an excerpt to see how it will look like in > > DTS? > > Yes, it looks like this now: > > i2c@0x2000 { > compatible = "snps,designware-i2c"; > #address-cells = <1>; > #size-cells = <0>; > reg = <0x2000 0x100>; > clock-frequency = <400000>; > clocks = <&i2cclk>; > interrupts = <0>; > > eeprom@64 { > compatible = "linux,slave-24c02"; > reg = <0x40000064>; > }; > }; +1 to Carlos' comment. > >   > > > > > - dev->functionality = I2C_FUNC_10BIT_ADDR | > > > > > DW_IC_DEFAULT_FUNCTIONALITY; > > > > > - > > > > > - i2c_dw_configure_master(pdev); > > > > > + if (ACPI_HANDLE(&pdev->dev) == NULL) { > > > > > > > > I don't think you need this at all. > > > > > > This is to avoid the use of the "ifdef" style I used before. > > > > My point is to drop it completely. > > > > > > > > > > > + device_for_each_child_node(&pdev->dev, child) > > > > > { > > > > > > > > This is resource agnostic. > > > > > > > > > + fwnode_property_read_u32(child, > > > > > "reg", > > > > > ®); > > > > > > > > This is as well. > > > > > > Are you suggesting I use of_ functions? > > > > Nope. See above. So, ACPI has a property to support slave mode for I2CSerialBus() macro. I would propose to create a helper function in i2c-core.c which will be responsible for mode detection ... i2c_slave_mode_detect() { ... if (IS_BUILTIN(CONFIG_OF) && dev->of_node) { ... (use of_*() here) ... } else if (IS_BUILTIN(CONFIG_ACPI) && ACPI_HANDLE(dev)) dev_dbg(..., "ACPI slave is not supported yet\n"); ... to master ... } else { ... default to master ... } } EXPORT_...(); Make it as a separate patch. -- Andy Shevchenko Intel Finland Oy