From mboxrd@z Thu Jan 1 00:00:00 1970 From: Shawn Guo Subject: Re: [PATCH v2 6/9] misc: Generic on-chip SRAM allocation driver Date: Mon, 3 Sep 2012 10:19:53 +0800 Message-ID: <20120903021950.GD2362@S2101-09.ap.freescale.net> References: <1346405224-20399-1-git-send-email-p.zabel@pengutronix.de> <1346405224-20399-7-git-send-email-p.zabel@pengutronix.de> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Return-path: Content-Disposition: inline In-Reply-To: <1346405224-20399-7-git-send-email-p.zabel@pengutronix.de> Sender: linux-kernel-owner@vger.kernel.org To: Philipp Zabel Cc: linux-kernel@vger.kernel.org, linux-arm-kernel@lists.infradead.org, Grant Likely , Rob Herring , Paul Gortmaker , Richard Zhao , Huang Shijie , Dong Aisheng , kernel@pengutronix.de, devicetree-discuss@lists.ozlabs.org List-Id: devicetree@vger.kernel.org On Fri, Aug 31, 2012 at 11:27:01AM +0200, Philipp Zabel wrote: > This driver requests and remaps a memory region as configured in the > device tree. It serves memory from this region via the genalloc API. > > Other drivers can retrieve the genalloc pool from a phandle pointing > to this drivers' device node in the device tree. > > Signed-off-by: Philipp Zabel > --- > drivers/misc/Kconfig | 8 ++++ > drivers/misc/Makefile | 1 + > drivers/misc/sram.c | 105 +++++++++++++++++++++++++++++++++++++++++++++++++ > 3 files changed, 114 insertions(+) > create mode 100644 drivers/misc/sram.c > > diff --git a/drivers/misc/Kconfig b/drivers/misc/Kconfig > index 98a442d..8a55284 100644 > --- a/drivers/misc/Kconfig > +++ b/drivers/misc/Kconfig > @@ -509,6 +509,14 @@ config USB_SWITCH_FSA9480 > stereo and mono audio, video, microphone and UART data to use > a common connector port. > > +config SRAM > + bool "Generic on-chip SRAM driver\n" Remove the "\n". And "depends on HAS_IOMEM"? > + select GENERIC_ALLOCATOR > + help > + This driver allows to declare a memory region to be managed > + by the genalloc API. It is supposed to be used for small > + on-chip SRAM areas found on many ARM SoCs. > + > source "drivers/misc/c2port/Kconfig" > source "drivers/misc/eeprom/Kconfig" > source "drivers/misc/cb710/Kconfig" > diff --git a/drivers/misc/Makefile b/drivers/misc/Makefile > index b88df7a..ccc759a 100644 > --- a/drivers/misc/Makefile > +++ b/drivers/misc/Makefile > @@ -50,3 +50,4 @@ obj-y += carma/ > obj-$(CONFIG_USB_SWITCH_FSA9480) += fsa9480.o > obj-$(CONFIG_ALTERA_STAPL) +=altera-stapl/ > obj-$(CONFIG_INTEL_MEI) += mei/ > +obj-$(CONFIG_SRAM) += sram.o > diff --git a/drivers/misc/sram.c b/drivers/misc/sram.c > new file mode 100644 > index 0000000..c5cf67e > --- /dev/null > +++ b/drivers/misc/sram.c > @@ -0,0 +1,105 @@ > +/* > + * Generic on-chip SRAM allocation driver > + * > + * Copyright (C) 2012 Philipp Zabel, Pengutronix > + * > + * This program is free software; you can redistribute it and/or > + * modify it under the terms of the GNU General Public License > + * as published by the Free Software Foundation; either version 2 > + * of the License, or (at your option) any later version. > + * This program is distributed in the hope that it will be useful, > + * but WITHOUT ANY WARRANTY; without even the implied warranty of > + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the > + * GNU General Public License for more details. > + * > + * You should have received a copy of the GNU General Public License > + * along with this program; if not, write to the Free Software > + * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, > + * MA 02110-1301, USA. > + */ > + > +#include > +#include > +#include > +#include > +#include > +#include > +#include > + > +struct sram_dev { > + struct gen_pool *pool; > +}; > + > +static int __devinit sram_probe(struct platform_device *pdev) > +{ > + void __iomem *virt_base; > + struct sram_dev *sram; > + struct resource *res; > + unsigned long size; > + int ret; > + > + res = platform_get_resource(pdev, IORESOURCE_MEM, 0); > + if (!res) > + return -EINVAL; > + > + size = resource_size(res); > + > + virt_base = devm_request_and_ioremap(&pdev->dev, res); > + if (!virt_base) > + return -ENOMEM; The kerneldoc of devm_request_and_ioremap suggests -EADDRNOTAVAIL. Regards, Shawn > + > + sram = devm_kzalloc(&pdev->dev, sizeof(*sram), GFP_KERNEL); > + if (!sram) > + return -ENOMEM; > + > + sram->pool = gen_pool_create(PAGE_SHIFT, -1); > + if (!sram->pool) > + return -ENOMEM; > + > + ret = gen_pool_add_virt(sram->pool, (unsigned long)virt_base, > + res->start, size, -1); > + if (ret < 0) { > + gen_pool_destroy(sram->pool); > + return ret; > + } > + > + platform_set_drvdata(pdev, sram); > + > + dev_dbg(&pdev->dev, "SRAM pool: %ld KiB @ 0x%p\n", size / 1024, virt_base); > + > + return 0; > +} > + > +static int __devexit sram_remove(struct platform_device *pdev) > +{ > + struct sram_dev *sram = platform_get_drvdata(pdev); > + > + if (gen_pool_avail(sram->pool) < gen_pool_size(sram->pool)) > + dev_dbg(&pdev->dev, "removed while SRAM allocated\n"); > + > + gen_pool_destroy(sram->pool); > + > + return 0; > +} > + > +#ifdef CONFIG_OF > +static struct of_device_id sram_dt_ids[] = { > + { .compatible = "sram" }, > + { /* sentinel */ } > +}; > +#endif > + > +static struct platform_driver sram_driver = { > + .driver = { > + .name = "sram", > + .of_match_table = of_match_ptr(sram_dt_ids), > + }, > + .probe = sram_probe, > + .remove = __devexit_p(sram_remove), > +}; > + > +module_platform_driver(sram_driver); > + > +MODULE_LICENSE("GPL"); > +MODULE_AUTHOR("Philipp Zabel, Pengutronix"); > +MODULE_DESCRIPTION("Generic SRAM allocator driver"); > -- > 1.7.10.4 >