From mboxrd@z Thu Jan 1 00:00:00 1970 From: Tao Ren Date: Wed, 11 Mar 2020 17:09:31 -0700 Subject: [PATCH v2] usb: gadget: aspeed: improve vhub port irq handling In-Reply-To: <481e9b7d40c51505518a34ddc2515d3200dbf158.camel@kernel.crashing.org> References: <20200305234746.1002-1-rentao.bupt@gmail.com> <481e9b7d40c51505518a34ddc2515d3200dbf158.camel@kernel.crashing.org> Message-ID: <20200312000930.GA3956@taoren-ubuntu-R90MNF91> List-Id: To: linux-aspeed@lists.ozlabs.org MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Hi Ben, On Wed, Mar 11, 2020 at 12:31:22PM +1100, Benjamin Herrenschmidt wrote: > On Thu, 2020-03-05 at 15:47 -0800, rentao.bupt at gmail.com wrote: > > From: Tao Ren > > > > This patch evaluates vhub ports' irq mask before going through per-port > > irq handling one by one, which helps to speed up irq handling in case > > there is no port interrupt. > > > > Signed-off-by: Tao Ren > > --- > > Changes in v2: > > - use "for_each_set_bit" to speed up port irq handling. > > > > drivers/usb/gadget/udc/aspeed-vhub/core.c | 11 ++++++++--- > > drivers/usb/gadget/udc/aspeed-vhub/vhub.h | 8 +++----- > > 2 files changed, 11 insertions(+), 8 deletions(-) > > > > diff --git a/drivers/usb/gadget/udc/aspeed-vhub/core.c b/drivers/usb/gadget/udc/aspeed-vhub/core.c > > index f8d35dd60c34..af2dbd405361 100644 > > --- a/drivers/usb/gadget/udc/aspeed-vhub/core.c > > +++ b/drivers/usb/gadget/udc/aspeed-vhub/core.c > > @@ -134,11 +134,14 @@ static irqreturn_t ast_vhub_irq(int irq, void *data) > > } > > > > /* Handle device interrupts */ > > - for (i = 0; i < vhub->max_ports; i++) { > > - u32 dev_mask = VHUB_IRQ_DEVICE1 << i; > > + if (istat & vhub->port_irq_mask) { > > + int offset = VHUB_IRQ_DEV1_BIT; > > + int size = VHUB_IRQ_DEV1_BIT + vhub->max_ports; > > > > - if (istat & dev_mask) > > + for_each_set_bit_from(offset, (unsigned long *)&istat, size) > > That type cast is very bad. It will not work on big endian for example > (yes this driver isn't used on big endian today but still). > > Please assign istat to an unsigned long (or make it unsigned long to > begin with). Thanks for pointing it out. Will fix it in v3. Cheers, Tao