Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754258Ab1DGPDb (ORCPT ); Thu, 7 Apr 2011 11:03:31 -0400 Received: from mga03.intel.com ([143.182.124.21]:40727 "EHLO mga03.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751019Ab1DGPD3 (ORCPT ); Thu, 7 Apr 2011 11:03:29 -0400 X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="4.63,317,1299484800"; d="scan'208";a="415449785" Date: Thu, 7 Apr 2011 17:03:23 +0200 From: Samuel Ortiz To: Grant Likely Cc: Felipe Balbi , Greg KH , Andres Salomon , linux-kernel@vger.kernel.org, Mark Brown , khali@linux-fr.org, ben-linux@fluff.org, Peter Korsgaard , Mauro Carvalho Chehab , David Brownell , linux-i2c@vger.kernel.org, linux-media@vger.kernel.org, netdev@vger.kernel.org, spi-devel-general@lists.sourceforge.net, Mocean Laboratories Subject: Re: [PATCH 07/19] timberdale: mfd_cell is now implicitly available to drivers Message-ID: <20110407150322.GB3923@sortiz-mobl> References: <20110404100314.GC2751@sortiz-mobl> <20110405030428.GB29522@ponder.secretlab.ca> <20110406152322.GA2757@sortiz-mobl> <20110406155805.GA20095@suse.de> <20110406170537.GB2757@sortiz-mobl> <20110406175647.GA8048@suse.de> <20110406184733.GD2757@sortiz-mobl> <20110406185902.GN25654@legolas.emea.dhcp.ti.com> <20110407133717.GA3923@sortiz-mobl> <20110407143515.GC26452@angua.secretlab.ca> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20110407143515.GC26452@angua.secretlab.ca> User-Agent: Mutt/1.5.20 (2009-06-14) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 5408 Lines: 139 On Thu, Apr 07, 2011 at 07:35:15AM -0700, Grant Likely wrote: > > Below is a patch for the Xilinx SPI example. Although this would fix the > > issue, we'd still have to do that on device per device basis. I had a similar > > solution where MFD drivers would set a flag for sub drivers that don't need > > any of the MFD bits. In that case the MFD core code would just forward the > > platform data, instead of embedding it through an MFD cell. > > platform_data is already a fiddly bit where you don't know what > structure type platform_data points at; it is implicitly known and > easy to get wrong. This solution makes me *very* nervous > because it would become even easier to get a mismatch on the > platform_data pointer type. How would that be more error prone than say a board file instantiating a platform device after having set the platform_data pointer to point to an implicitely know structure reference ? Cheers, Samuel. P.S.: Would you be ok with something like the patch below ? > > --- > > drivers/mfd/timberdale.c | 8 ++++---- > > drivers/spi/xilinx_spi.c | 19 ++++++++++++++++++- > > include/linux/mfd/core.h | 3 +++ > > 3 files changed, 25 insertions(+), 5 deletions(-) > > > > diff --git a/drivers/mfd/timberdale.c b/drivers/mfd/timberdale.c > > index 94c6c8a..c9220ce 100644 > > --- a/drivers/mfd/timberdale.c > > +++ b/drivers/mfd/timberdale.c > > @@ -416,7 +416,7 @@ static __devinitdata struct mfd_cell timberdale_cells_bar0_cfg0[] = { > > .mfd_data = &timberdale_radio_platform_data, > > }, > > { > > - .name = "xilinx_spi", > > + .name = "mfd_xilinx_spi", > > .num_resources = ARRAY_SIZE(timberdale_spi_resources), > > .resources = timberdale_spi_resources, > > .mfd_data = &timberdale_xspi_platform_data, > > @@ -476,7 +476,7 @@ static __devinitdata struct mfd_cell timberdale_cells_bar0_cfg1[] = { > > .mfd_data = &timberdale_radio_platform_data, > > }, > > { > > - .name = "xilinx_spi", > > + .name = "mfd_xilinx_spi", > > .num_resources = ARRAY_SIZE(timberdale_spi_resources), > > .resources = timberdale_spi_resources, > > .mfd_data = &timberdale_xspi_platform_data, > > @@ -526,7 +526,7 @@ static __devinitdata struct mfd_cell timberdale_cells_bar0_cfg2[] = { > > .mfd_data = &timberdale_radio_platform_data, > > }, > > { > > - .name = "xilinx_spi", > > + .name = "mfd_xilinx_spi", > > .num_resources = ARRAY_SIZE(timberdale_spi_resources), > > .resources = timberdale_spi_resources, > > .mfd_data = &timberdale_xspi_platform_data, > > @@ -570,7 +570,7 @@ static __devinitdata struct mfd_cell timberdale_cells_bar0_cfg3[] = { > > .mfd_data = &timberdale_radio_platform_data, > > }, > > { > > - .name = "xilinx_spi", > > + .name = "mfd_xilinx_spi", > > .num_resources = ARRAY_SIZE(timberdale_spi_resources), > > .resources = timberdale_spi_resources, > > .mfd_data = &timberdale_xspi_platform_data, > > diff --git a/drivers/spi/xilinx_spi.c b/drivers/spi/xilinx_spi.c > > index c69c6f2..3287b84 100644 > > --- a/drivers/spi/xilinx_spi.c > > +++ b/drivers/spi/xilinx_spi.c > > @@ -471,7 +471,11 @@ static int __devinit xilinx_spi_probe(struct platform_device *dev) > > struct spi_master *master; > > u8 i; > > > > - pdata = mfd_get_data(dev); > > + if (platform_get_device_id(dev) && > > + platform_get_device_id(dev)->driver_data & MFD_PLATFORM_DEVICE) > > + pdata = mfd_get_data(dev); > > + else > > + pdata = dev->dev.platform_data; > > if (pdata) { > > num_cs = pdata->num_chipselect; > > little_endian = pdata->little_endian; > > @@ -530,6 +534,18 @@ static int __devexit xilinx_spi_remove(struct platform_device *dev) > > /* work with hotplug and coldplug */ > > MODULE_ALIAS("platform:" XILINX_SPI_NAME); > > > > +static const struct platform_device_id xilinx_spi_id_table[] = { > > + { > > + .name = XILINX_SPI_NAME, > > + }, > > + { > > + .name = "mfd_xilinx_spi", > > + .driver_data = MFD_PLATFORM_DEVICE, > > + }, > > + { }, /* Terminating Entry */ > > +}; > > +MODULE_DEVICE_TABLE(platform, xilinx_spi_id_table); > > + > > static struct platform_driver xilinx_spi_driver = { > > .probe = xilinx_spi_probe, > > .remove = __devexit_p(xilinx_spi_remove), > > @@ -538,6 +554,7 @@ static struct platform_driver xilinx_spi_driver = { > > .owner = THIS_MODULE, > > .of_match_table = xilinx_spi_of_match, > > }, > > + .id_table = xilinx_spi_id_table, > > }; > > > > static int __init xilinx_spi_pltfm_init(void) > > diff --git a/include/linux/mfd/core.h b/include/linux/mfd/core.h > > index ad1b19a..13f31f4 100644 > > --- a/include/linux/mfd/core.h > > +++ b/include/linux/mfd/core.h > > @@ -89,6 +89,9 @@ static inline const struct mfd_cell *mfd_get_cell(struct platform_device *pdev) > > return pdev->dev.platform_data; > > } > > > > +/* */ > > +#define MFD_PLATFORM_DEVICE BIT(0) > > + > > /* > > * Given a platform device that's been created by mfd_add_devices(), fetch > > * the .mfd_data entry from the mfd_cell that created it. > > > > > > -- > > Intel Open Source Technology Centre > > http://oss.intel.com/ -- Intel Open Source Technology Centre http://oss.intel.com/ -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/