Xhci_handshake() implements the algorithm already captured by
readl_poll_timeout(). Convert the former to use the latter to avoid
repetition.
Signed-off-by: Andrey Smirnov <[email protected]>
Cc: Mathias Nyman <[email protected]>
Cc: Greg Kroah-Hartman <[email protected]>
Cc: [email protected]
Cc: [email protected]
---
drivers/usb/host/xhci.c | 22 ++++++++++------------
1 file changed, 10 insertions(+), 12 deletions(-)
diff --git a/drivers/usb/host/xhci.c b/drivers/usb/host/xhci.c
index 005e65922608..1b5306001340 100644
--- a/drivers/usb/host/xhci.c
+++ b/drivers/usb/host/xhci.c
@@ -9,6 +9,7 @@
*/
#include <linux/pci.h>
+#include <linux/iopoll.h>
#include <linux/irq.h>
#include <linux/log2.h>
#include <linux/module.h>
@@ -52,7 +53,6 @@ static bool td_on_ring(struct xhci_td *td, struct xhci_ring *ring)
return false;
}
-/* TODO: copied from ehci-hcd.c - can this be refactored? */
/*
* xhci_handshake - spin reading hc until handshake completes or fails
* @ptr: address of hc register to be read
@@ -69,18 +69,16 @@ static bool td_on_ring(struct xhci_td *td, struct xhci_ring *ring)
int xhci_handshake(void __iomem *ptr, u32 mask, u32 done, int usec)
{
u32 result;
+ int ret;
- do {
- result = readl(ptr);
- if (result == ~(u32)0) /* card removed */
- return -ENODEV;
- result &= mask;
- if (result == done)
- return 0;
- udelay(1);
- usec--;
- } while (usec > 0);
- return -ETIMEDOUT;
+ ret = readl_poll_timeout(ptr, result,
+ (result & mask) == done ||
+ result == U32_MAX,
+ 1, usec);
+ if (result == U32_MAX) /* card removed */
+ return -ENODEV;
+
+ return ret;
}
/*
--
2.20.1
On 07.02.2019 02:03, Andrey Smirnov wrote:
> Xhci_handshake() implements the algorithm already captured by
> readl_poll_timeout(). Convert the former to use the latter to avoid
> repetition.
readl_poll_timeout() doesn't really work here as it might sleep.
iopoll.h:
/**
* readx_poll_timeout - Periodically poll an address until a condition is met or a timeout occurs
*
...
* Returns 0 on success and -ETIMEDOUT upon a timeout. In either
* case, the last read value at @addr is stored in @val. Must not
* be called from atomic context if sleep_us or timeout_us are used.
-Mathias
Hi,
Mathias Nyman <[email protected]> writes:
> On 07.02.2019 02:03, Andrey Smirnov wrote:
>> Xhci_handshake() implements the algorithm already captured by
>> readl_poll_timeout(). Convert the former to use the latter to avoid
>> repetition.
>
> readl_poll_timeout() doesn't really work here as it might sleep.
>
> iopoll.h:
>
> /**
> * readx_poll_timeout - Periodically poll an address until a condition is met or a timeout occurs
> *
> ...
> * Returns 0 on success and -ETIMEDOUT upon a timeout. In either
> * case, the last read value at @addr is stored in @val. Must not
> * be called from atomic context if sleep_us or timeout_us are used.
readl_poll_timeout_atomic()?
--
balbi
On Thu, Feb 7, 2019 at 12:27 AM Mathias Nyman
<[email protected]> wrote:
>
> On 07.02.2019 02:03, Andrey Smirnov wrote:
> > Xhci_handshake() implements the algorithm already captured by
> > readl_poll_timeout(). Convert the former to use the latter to avoid
> > repetition.
>
> readl_poll_timeout() doesn't really work here as it might sleep.
>
> iopoll.h:
>
> /**
> * readx_poll_timeout - Periodically poll an address until a condition is met or a timeout occurs
> *
> ...
> * Returns 0 on success and -ETIMEDOUT upon a timeout. In either
> * case, the last read value at @addr is stored in @val. Must not
> * be called from atomic context if sleep_us or timeout_us are used.
>
> -Mathias
Shoot, missed this part. Will change to readl_poll_timeout_atomic() in v2.
Thanks,
Andrey Smirnov