Re: [PATCH 03/20] Staging: ipack/bridges/tpci200: provide new callbacks to tpci200

[Jens Taprogge <jens.taprogge@taprogge.org>]

On Tue, Sep 11, 2012 at 11:47:02AM +0300, Dan Carpenter wrote:
> 
> I had a few style comments on this patchset.  Nothing that couldn't
> be fixed later.
> 
> On Mon, Sep 10, 2012 at 10:51:41AM +0200, Samuel Iglesias Gonsálvez wrote:
> > From: Jens Taprogge <jens.taprogge@taprogge.org>
> > 
> > Provide get_clockrate, set_clockrate, get_error, get_timeout and reset_timeout
> > callbacks.
> > 
> > Signed-off-by: Jens Taprogge <jens.taprogge@taprogge.org>
> > Signed-off-by: Samuel Iglesias Gonsálvez <siglesias@igalia.com>
> > ---
> >  drivers/staging/ipack/bridges/tpci200.c |  107 +++++++++++++++++++++++++++++++
> >  1 file changed, 107 insertions(+)
> > 
> > diff --git a/drivers/staging/ipack/bridges/tpci200.c b/drivers/staging/ipack/bridges/tpci200.c
> > index 4383953..861b00d 100644
> > --- a/drivers/staging/ipack/bridges/tpci200.c
> > +++ b/drivers/staging/ipack/bridges/tpci200.c
> > @@ -14,6 +14,20 @@
> >  #include <linux/module.h>
> >  #include "tpci200.h"
> >  
> > +static u16 tpci200_status_timeout[] = {
> > +	TPCI200_A_TIMEOUT,
> > +	TPCI200_B_TIMEOUT,
> > +	TPCI200_C_TIMEOUT,
> > +	TPCI200_D_TIMEOUT,
> > +};
> > +
> > +static u16 tpci200_status_error[] = {
> > +	TPCI200_A_ERROR,
> > +	TPCI200_B_ERROR,
> > +	TPCI200_C_ERROR,
> > +	TPCI200_D_ERROR,
> > +};
> > +
> >  static struct ipack_bus_ops tpci200_bus_ops;
> >  
> >  static int tpci200_slot_unregister(struct ipack_device *dev);
> > @@ -507,6 +521,94 @@ out_unlock:
> >  	return res;
> >  }
> >  
> > +static int tpci200_get_clockrate(struct ipack_device *dev)
> > +{
> > +	struct tpci200_board *tpci200 = check_slot(dev);
> > +	__le16 __iomem *addr;
> 
> The point of the underscores in the __le16 is that you don't want to
> pollute user space headers in glibc with a bunch of kernel typedefs.
> It is not needed here.  (Or if it is, then we would need to replace
> the u16 uses as well).

I was under the impression that "__le16" is used to indicate the
byteorder of the pointed to memory.  As far as I can see that
information is lost when we use u16.  Am I missing something?

Which u16 uses are you referring to?

> 
> > +
> > +	if (!tpci200)
> > +		return -ENODEV;
> > +
> > +	addr = &tpci200->info->interface_regs->control[dev->slot];
> > +	return (ioread16(addr) & TPCI200_CLK32) ? 32 : 8;
> > +}
> > +
> > +static int tpci200_set_clockrate(struct ipack_device *dev, int mherz)
> > +{
> > +	struct tpci200_board *tpci200 = check_slot(dev);
> > +	__le16 __iomem *addr;
> > +	u16 reg;
> > +
> > +	if (!tpci200)
> > +		return -ENODEV;
> > +
> > +	addr = &tpci200->info->interface_regs->control[dev->slot];
> > +
> > +	/* Ensure the control register is not changed by another task after we
> > +	 * have read it. */
> > +	mutex_lock(&tpci200->mutex);
> > +	reg = ioread16(addr);
> > +	switch (mherz) {
> > +	case 8:
> > +		reg &= ~(TPCI200_CLK32); break;
> > +	case 32:
> > +		reg |= TPCI200_CLK32; break;
> 
> Put the breaks on the next line so that we can see them.  At first I
> thought it fell through.
> 
> > +	default:
> > +		mutex_unlock(&tpci200->mutex);
> > +		return -EINVAL;
> > +	}
> > +	iowrite16(reg, addr);
> > +	mutex_unlock(&tpci200->mutex);
> > +	return 0;
> > +}
> > +
> > +static int tpci200_get_error(struct ipack_device *dev)
> > +{
> > +	struct tpci200_board *tpci200 = check_slot(dev);
> > +	__le16 __iomem *addr;
> > +	u16 mask;
> > +
> > +	if (!tpci200)
> > +		return -ENODEV;
> > +
> > +	addr = &tpci200->info->interface_regs->status;
> > +	mask = tpci200_status_error[dev->slot];
> > +	return (ioread16(addr) & mask) ? 1 : 0;
> > +}
> > +
> > +static int tpci200_get_timeout(struct ipack_device *dev)
> > +{
> > +	struct tpci200_board *tpci200 = check_slot(dev);
> > +	__le16 __iomem *addr;
> > +	u16 mask;
> > +
> > +	if (!tpci200)
> > +		return -ENODEV;
> > +
> > +	addr = &tpci200->info->interface_regs->status;
> > +	mask = tpci200_status_timeout[dev->slot];
> > +
> > +	return (ioread16(addr) & mask) ? 1 : 0;
> > +}
> > +
> > +static int tpci200_reset_timeout(struct ipack_device *dev)
> > +{
> > +	struct tpci200_board *tpci200 = check_slot(dev);
> > +	__le16 __iomem *addr;
> > +	u16 mask;
> > +
> > +	if (!tpci200)
> > +		return -ENODEV;
> > +
> > +	addr = &tpci200->info->interface_regs->status;
> > +	mask = tpci200_status_timeout[dev->slot];
> > +
> > +	iowrite16(mask, addr);
> > +	return 0;
> > +}
> > +
> > +
> > +
> 
> Only one blank line is here.
> 
> >  static void tpci200_uninstall(struct tpci200_board *tpci200)
> >  {
> >  	int i;
> > @@ -524,6 +626,11 @@ static struct ipack_bus_ops tpci200_bus_ops = {
> >  	.request_irq = tpci200_request_irq,
> >  	.free_irq = tpci200_free_irq,
> >  	.remove_device = tpci200_slot_unregister,
> > +	.get_clockrate = tpci200_get_clockrate,
> > +	.set_clockrate = tpci200_set_clockrate,
> > +	.get_error     = tpci200_get_error,
> > +	.get_timeout   = tpci200_get_timeout,
> > +	.reset_timeout = tpci200_reset_timeout,
> >  };
> >  
> >  static int tpci200_install(struct tpci200_board *tpci200)
> > -- 
> > 1.7.10.4
> > 
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