linux-kernel - Re: [PATCH v1 1/5] mfd: lpc

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Date:	Mon, 01 Sep 2014 13:21:43 +0300
From:	Andy Shevchenko <andriy.shevchenko@...ux.intel.com>
To:	Lee Jones <lee.jones@...aro.org>
Cc:	Bjorn Helgaas <bhelgaas@...gle.com>, linux-kernel@...r.kernel.org,
	Samuel Ortiz <sameo@...ux.intel.com>,
	Chang Rebecca Swee Fun <rebecca.swee.fun.chang@...el.com>
Subject: Re: [PATCH v1 1/5] mfd: lpc_sch: reduce duplicate code

On Mon, 2014-09-01 at 10:13 +0100, Lee Jones wrote:
> On Fri, 22 Aug 2014, Andy Shevchenko wrote:
> 
> > This patch refactors the driver to use helper functions instead of
> > copy'n'pasted pieces of code.
> > 
> > Tested-by: Chang Rebecca Swee Fun <rebecca.swee.fun.chang@...el.com>
> > Signed-off-by: Andy Shevchenko <andriy.shevchenko@...ux.intel.com>
> > ---
> >  drivers/mfd/lpc_sch.c | 146 ++++++++++++++++++++++----------------------------
> >  1 file changed, 64 insertions(+), 82 deletions(-)
> > 
> > diff --git a/drivers/mfd/lpc_sch.c b/drivers/mfd/lpc_sch.c
> > index 4ee7550..0f01ef0 100644
> > --- a/drivers/mfd/lpc_sch.c
> > +++ b/drivers/mfd/lpc_sch.c
> > @@ -40,41 +40,6 @@
> 
> [...]

Thanks for review, my answers below.

> 
> > -static int lpc_sch_probe(struct pci_dev *dev,
> > -				const struct pci_device_id *id)
> > +static int lpc_sch_get_io(struct pci_dev *pdev, int where, const char *name,
> > +			  struct resource *res, int size)
> >  {
> >  	unsigned int base_addr_cfg;
> >  	unsigned short base_addr;
> > -	int i, cells = 0;
> > -	int ret;
> >  
> > -	pci_read_config_dword(dev, SMBASE, &base_addr_cfg);
> > +	pci_read_config_dword(pdev, where, &base_addr_cfg);
> >  	base_addr = 0;
> >  	if (!(base_addr_cfg & (1 << 31)))
> > -		dev_warn(&dev->dev, "Decode of the SMBus I/O range disabled\n");
> > +		dev_warn(&pdev->dev, "Decode of the %s I/O range disabled\n",
> > +			 name);
> >  	else
> >  		base_addr = (unsigned short)base_addr_cfg;
> >  
> >  	if (base_addr == 0) {
> > -		dev_warn(&dev->dev, "I/O space for SMBus uninitialized\n");
> > -	} else {
> > -		lpc_sch_cells[cells++] = isch_smbus_cell;
> > -		smbus_sch_resource.start = base_addr;
> > -		smbus_sch_resource.end = base_addr + SMBUS_IO_SIZE - 1;
> > +		dev_warn(&pdev->dev, "I/O space for %s uninitialized\n", name);
> > +		return -ENODEV;
> 
> If you're going to return an error, you need to use dev_err() above.

Okay.

> >  	}
> >  
> > -	pci_read_config_dword(dev, GPIOBASE, &base_addr_cfg);
> > -	base_addr = 0;
> > -	if (!(base_addr_cfg & (1 << 31)))
> > -		dev_warn(&dev->dev, "Decode of the GPIO I/O range disabled\n");
> > +	res->start = base_addr;
> > +	res->end = base_addr + size - 1;
> > +	res->flags = IORESOURCE_IO;
> > +
> > +	return 0;
> > +}
> > +
> > +static int lpc_sch_populate_cell(struct pci_dev *pdev, int where,
> > +				 const char *name, int size, int id,
> > +				 struct mfd_cell *cell)
> > +{
> > +	struct resource *res;
> > +	int ret;
> > +
> > +	res = devm_kzalloc(&pdev->dev, sizeof(*res), GFP_KERNEL);
> > +	if (!res)
> > +		return -ENOMEM;
> > +
> > +	ret = lpc_sch_get_io(pdev, where, name, res, size);
> > +	if (ret)
> > +		return ret;
> > +
> > +	memset(cell, 0, sizeof(*cell));
> > +
> > +	cell->name = name;
> > +	cell->resources = res;
> > +	cell->num_resources = 1;
> > +	cell->ignore_resource_conflicts = true;
> > +	cell->id = id;
> > +
> > +	return 0;
> > +}
> > +
> > +static int lpc_sch_probe(struct pci_dev *dev,
> > +			 const struct pci_device_id *id)
> > +{
> > +	struct mfd_cell lpc_sch_cells[3];
> > +	int size, cells = 0;
> > +	int ret;
> > +
> > +	ret = lpc_sch_populate_cell(dev, SMBASE, "isch_smbus", SMBUS_IO_SIZE,
> > +				    id->device, &lpc_sch_cells[cells]);
> > +	if (!ret)
> > +		cells++;
> 
> You're masking errors here.  You need to return on error.

No, I don't. It's a local error, I just need to understand if the HW has
or hasn't the IP part we're looking for.

I could, let's say, return true or false, if you prefer, with the above
meaning.


-- 
Andy Shevchenko <andriy.shevchenko@...el.com>
Intel Finland Oy

--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@...r.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/