Subject: Re: [PATCH v2 5/7] [PATCH 5/8] can: SJA1000 generic platform bus driver

From: Wolfgang Grandegger <[email-masked]>
Date: Fri, 15 May 2009 11:35:06 +0200

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 <[email-masked]>
>> Signed-off-by: Wolfgang Grandegger <[email-masked]>
>> Signed-off-by: Marc Kleine-Budde <[email-masked]>
>> Signed-off-by: Oliver Hartkopp <[email-masked]>
>> ---
>>  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 <[email-masked]>
>> + *
>> + * 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 <linux/kernel.h>
>> +#include <linux/module.h>
>> +#include <linux/interrupt.h>
>> +#include <linux/netdevice.h>
>> +#include <linux/delay.h>
>> +#include <linux/pci.h>
>> +#include <linux/platform_device.h>
>> +#include <linux/irq.h>
>> +#include <linux/can.h>
>> +#include <linux/can/dev.h>
>> +#include <linux/can/platform/sja1000.h>
>> +#include <linux/io.h>
>> +
>> +#include "sja1000.h"
>> +
>> +#define DRV_NAME "sja1000_platform"
>> +
>> +MODULE_AUTHOR("Sascha Hauer <[email-masked]>");
>> +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.

Wolfgang.