From mboxrd@z Thu Jan 1 00:00:00 1970 From: Sascha Hauer Subject: Re: [PATCH v2 5/7] [PATCH 5/8] can: SJA1000 generic platform bus driver Date: Fri, 15 May 2009 14:07:12 +0200 Message-ID: <20090515120711.GE26519@pengutronix.de> References: <20090512092757.048938233@denx.de> <20090512092757.894204198@denx.de> <20090514064633.GT29278@pengutronix.de> <4A0D374A.8080006@grandegger.com> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Cc: netdev@vger.kernel.org, linux-kernel@vger.kernel.org, Marc Kleine-Budde , Oliver Hartkopp To: Wolfgang Grandegger Return-path: Received: from metis.ext.pengutronix.de ([92.198.50.35]:49075 "EHLO metis.ext.pengutronix.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752625AbZEOMHN (ORCPT ); Fri, 15 May 2009 08:07:13 -0400 Content-Disposition: inline In-Reply-To: <4A0D374A.8080006@grandegger.com> Sender: netdev-owner@vger.kernel.org List-ID: On Fri, May 15, 2009 at 11:35:06AM +0200, Wolfgang Grandegger wrote: > Hi Sascha, > > Sascha Hauer wrote: > > Hi Wolfgang, > > > > some comments inline. > > > > Sascha > > > > On Tue, May 12, 2009 at 11:28:02AM +0200, Wolfgang Grandegger wrote: > >> This driver adds support for the SJA1000 chips connected to the > >> "platform bus", which can be found on various embedded systems. > >> > >> Signed-off-by: Sascha Hauer > >> Signed-off-by: Wolfgang Grandegger > >> Signed-off-by: Marc Kleine-Budde > >> Signed-off-by: Oliver Hartkopp > >> --- > >> drivers/net/can/Kconfig | 10 + > >> drivers/net/can/sja1000/Makefile | 1 > >> drivers/net/can/sja1000/sja1000_platform.c | 169 +++++++++++++++++++++++++++++ > >> include/linux/can/platform/sja1000.h | 32 +++++ > >> 4 files changed, 212 insertions(+) > >> create mode 100644 drivers/net/can/sja1000/sja1000_platform.c > >> create mode 100644 include/linux/can/platform/sja1000.h > >> > >> Index: net-next-2.6/drivers/net/can/Kconfig > >> =================================================================== > >> --- net-next-2.6.orig/drivers/net/can/Kconfig 2009-05-12 10:47:25.747720647 +0200 > >> +++ net-next-2.6/drivers/net/can/Kconfig 2009-05-12 10:47:26.411720627 +0200 > >> @@ -41,6 +41,16 @@ > >> ---help--- > >> Driver for the SJA1000 CAN controllers from Philips or NXP > >> > >> +config CAN_SJA1000_PLATFORM > >> + depends on CAN_SJA1000 > >> + tristate "Generic Platform Bus based SJA1000 driver" > >> + ---help--- > >> + This driver adds support for the SJA1000 chips connected to > >> + the "platform bus" (Linux abstraction for directly to the > >> + processor attached devices). Which can be found on various > >> + boards from Phytec (http://www.phytec.de) like the PCM027, > >> + PCM038. > >> + > >> config CAN_DEBUG_DEVICES > >> bool "CAN devices debugging messages" > >> depends on CAN > >> Index: net-next-2.6/drivers/net/can/sja1000/Makefile > >> =================================================================== > >> --- net-next-2.6.orig/drivers/net/can/sja1000/Makefile 2009-05-12 10:47:25.753720385 +0200 > >> +++ net-next-2.6/drivers/net/can/sja1000/Makefile 2009-05-12 10:47:26.412720490 +0200 > >> @@ -3,5 +3,6 @@ > >> # > >> > >> obj-$(CONFIG_CAN_SJA1000) += sja1000.o > >> +obj-$(CONFIG_CAN_SJA1000_PLATFORM) += sja1000_platform.o > >> > >> ccflags-$(CONFIG_CAN_DEBUG_DEVICES) := -DDEBUG > >> Index: net-next-2.6/drivers/net/can/sja1000/sja1000_platform.c > >> =================================================================== > >> --- /dev/null 1970-01-01 00:00:00.000000000 +0000 > >> +++ net-next-2.6/drivers/net/can/sja1000/sja1000_platform.c 2009-05-12 10:47:26.416720502 +0200 > >> @@ -0,0 +1,169 @@ > >> +/* > >> + * Copyright (C) 2005 Sascha Hauer, Pengutronix > >> + * Copyright (C) 2007 Wolfgang Grandegger > >> + * > >> + * This program is free software; you can redistribute it and/or modify > >> + * it under the terms of the version 2 of the GNU General Public License > >> + * as published by the Free Software Foundation > >> + * > >> + * 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., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA > >> + */ > >> + > >> +#include > >> +#include > >> +#include > >> +#include > >> +#include > >> +#include > >> +#include > >> +#include > >> +#include > >> +#include > >> +#include > >> +#include > >> + > >> +#include "sja1000.h" > >> + > >> +#define DRV_NAME "sja1000_platform" > >> + > >> +MODULE_AUTHOR("Sascha Hauer "); > >> +MODULE_DESCRIPTION("Socket-CAN driver for SJA1000 on the platform bus"); > >> +MODULE_LICENSE("GPL v2"); > >> + > >> +static u8 sp_read_reg(const struct net_device *dev, int reg) > >> +{ > >> + return ioread8((void __iomem *)(dev->base_addr + reg)); > >> +} > >> + > >> +static void sp_write_reg(const struct net_device *dev, int reg, u8 val) > >> +{ > >> + iowrite8(val, (void __iomem *)(dev->base_addr + reg)); > >> +} > >> + > >> +static int sp_probe(struct platform_device *pdev) > >> +{ > >> + int err, irq; > >> + void __iomem *addr; > >> + struct net_device *dev; > >> + struct sja1000_priv *priv; > >> + struct resource *res_mem, *res_irq; > >> + struct sja1000_platform_data *pdata; > >> + > >> + pdata = pdev->dev.platform_data; > >> + if (!pdata) { > >> + dev_err(&pdev->dev, "No platform data provided!\n"); > >> + err = -ENODEV; > >> + goto exit; > >> + } > >> + > >> + res_mem = platform_get_resource(pdev, IORESOURCE_MEM, 0); > >> + res_irq = platform_get_resource(pdev, IORESOURCE_IRQ, 0); > >> + if (!res_mem || !res_irq) { > >> + err = -ENODEV; > >> + goto exit; > >> + } > >> + > >> + if (!request_mem_region(res_mem->start, > >> + res_mem->end - res_mem->start + 1, > >> + DRV_NAME)) { > > > > resource_size(res_mem) please, also for the other occurrences in this > > file > > OK. > > >> + err = -EBUSY; > >> + goto exit; > >> + } > >> + > >> + addr = ioremap_nocache(res_mem->start, > >> + res_mem->end - res_mem->start + 1); > >> + if (!addr) { > >> + err = -ENOMEM; > >> + goto exit_release; > >> + } > >> + > >> + irq = res_irq->start; > >> + if (res_irq->flags & IRQF_TRIGGER_MASK) > >> + set_irq_type(irq, res_irq->flags & IRQF_TRIGGER_MASK); > > > > You shouldn't use set_irq_type on not yet requested irqs but instead > > pass the flags to the real driver and pass them in request_irq. > > Why? I would require an extra member in the struct sja1000_priv. You change a resource you do not own. What if request_irq returns with -EBUSY? You already screwed up any other potential user. Sascha -- Pengutronix e.K. | | Industrial Linux Solutions | http://www.pengutronix.de/ | Peiner Str. 6-8, 31137 Hildesheim, Germany | Phone: +49-5121-206917-0 | Amtsgericht Hildesheim, HRA 2686 | Fax: +49-5121-206917-5555 |