On 11/06/2013 09:04 PM, Felipe Balbi wrote:
Hi,
On Wed, Nov 06, 2013 at 08:43:36PM +0400, Valentine wrote:
On 11/06/2013 07:45 PM, Felipe Balbi wrote:
Hi,
On Wed, Nov 06, 2013 at 12:33:26AM +0400, Valentine Barshak wrote:
This adds remove_phy flag to the HCD structure. If the flag is
set and if hcd->phy is valid, the phy is shutdown and released
whenever usb_add_hcd fails or usb_hcd_remove is called.
This can be used by the HCD drivers to auto-remove
the external USB phy when it is no longer needed.
Signed-off-by: Valentine Barshak <valentine.barshak@xxxxxxxxxxxxxxxxxx>
---
drivers/usb/core/hcd.c | 14 +++++++++++++-
include/linux/usb/hcd.h | 1 +
2 files changed, 14 insertions(+), 1 deletion(-)
diff --git a/drivers/usb/core/hcd.c b/drivers/usb/core/hcd.c
index d6a8d23..d939521 100644
--- a/drivers/usb/core/hcd.c
+++ b/drivers/usb/core/hcd.c
@@ -43,6 +43,7 @@
#include <linux/usb.h>
#include <linux/usb/hcd.h>
+#include <linux/usb/phy.h>
#include "usb.h"
@@ -2611,7 +2612,7 @@ int usb_add_hcd(struct usb_hcd *hcd,
*/
if ((retval = hcd_buffer_create(hcd)) != 0) {
dev_dbg(hcd->self.controller, "pool alloc failed\n");
- return retval;
+ goto err_remove_phy;
}
if ((retval = usb_register_bus(&hcd->self)) < 0)
@@ -2742,6 +2743,12 @@ err_allocate_root_hub:
usb_deregister_bus(&hcd->self);
err_register_bus:
hcd_buffer_destroy(hcd);
+err_remove_phy:
+ if (hcd->remove_phy && hcd->phy) {
+ usb_phy_shutdown(hcd->phy);
+ usb_put_phy(hcd->phy);
+ hcd->phy = NULL;
+ }
why do you need the flag at all ? If hcd->phy is valid, just casll
usb_phy_shutdown() followed by usb_put_phy(). Did you find any issues
with that ?
I haven't been able to test it with other platforms.
However, some drivers use devm_usb_get_phy_dev() and we may face refcounter issues
if we call usb_put_phy unconditionally.
Adding this flag seems safe enough and we doesn't affect other drivers.
then use devm_usb_get_phy_dev() here and remove the call from all other
drivers ;-)
The glue drivers may use different ways of getting the USB phy:
usb_get_phy; usb_get_phy_dev; devm_usb_get_phy_dev.
We can't consolidate phy getting here since usb_get_phy and usb_get_phy_dev are not equivalent.
So we let the glue drivers decide which way of getting/putting USB phy to use.
Thanks,
Val.
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