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

From: Jens Taprogge
Date: Wed Sep 12 2012 - 05:28:52 EST


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@xxxxxxxxxxxx>
> >
> > Provide get_clockrate, set_clockrate, get_error, get_timeout and reset_timeout
> > callbacks.
> >
> > Signed-off-by: Jens Taprogge <jens.taprogge@xxxxxxxxxxxx>
> > Signed-off-by: Samuel Iglesias Gonsálvez <siglesias@xxxxxxxxxx>
> > ---
> > 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
> >
> > _______________________________________________
> > devel mailing list
> > devel@xxxxxxxxxxxxxxxxxxxxxx
> > http://driverdev.linuxdriverproject.org/mailman/listinfo/devel
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