kernel.git/drivers/usb/gadget, branch linux-3.13.y

tty: Fix low_latency BUG

2014-04-22T23:49:20Z

commit a9c3f68f3cd8d55f809fbdb0c138ed061ea1bd25 upstream. The user-settable knob, low_latency, has been the source of several BUG reports which stem from flush_to_ldisc() running in interrupt context. Since 3.12, which added several sleeping locks (termios_rwsem and buf->lock) to the input processing path, the frequency of these BUG reports has increased. Note that changes in 3.12 did not introduce this regression; sleeping locks were first added to the input processing path with the removal of the BKL from N_TTY in commit a88a69c91256418c5907c2f1f8a0ec0a36f9e6cc, 'n_tty: Fix loss of echoed characters and remove bkl from n_tty' and later in commit 38db89799bdf11625a831c5af33938dcb11908b6, 'tty: throttling race fix'. Since those changes, executing flush_to_ldisc() in interrupt_context (ie, low_latency set), is unsafe. However, since most devices do not validate if the low_latency setting is appropriate for the context (process or interrupt) in which they receive data, some reports are due to misconfiguration. Further, serial dma devices for which dma fails, resort to interrupt receiving as a backup without resetting low_latency. Historically, low_latency was used to force wake-up the reading process rather than wait for the next scheduler tick. The effect was to trim multiple milliseconds of latency from when the process would receive new data. Recent tests [1] have shown that the reading process now receives data with only 10's of microseconds latency without low_latency set. Remove the low_latency rx steering from tty_flip_buffer_push(); however, leave the knob as an optional hint to drivers that can tune their rx fifos and such like. Cleanup stale code comments regarding low_latency. [1] https://lkml.org/lkml/2014/2/20/434 "Yay.. thats an annoying historical pain in the butt gone." -- Alan Cox Reported-by: Beat Bolli Reported-by: Pavel Roskin Acked-by: David Sterba Cc: Grant Edwards Cc: Stanislaw Gruszka Cc: Hal Murray Signed-off-by: Peter Hurley Signed-off-by: Alan Cox Signed-off-by: Greg Kroah-Hartman

usb: gadget: bcm63xx_udc: fix build failure on DMA channel code

2014-03-07T06:06:24Z

commit 2d1f7af3d60dd09794e0738a915d272c6c27abc5 upstream. Commit 3dc6475 ("bcm63xx_enet: add support Broadcom BCM6345 Ethernet") changed the ENETDMA[CS] macros such that they are no longer macros, but actual register offset definitions. The bcm63xx_udc driver was not updated, and as a result, causes the following build error to pop up: CC drivers/usb/gadget/u_ether.o drivers/usb/gadget/bcm63xx_udc.c: In function 'iudma_write': drivers/usb/gadget/bcm63xx_udc.c:642:24: error: called object '0' is not a function drivers/usb/gadget/bcm63xx_udc.c: In function 'iudma_reset_channel': drivers/usb/gadget/bcm63xx_udc.c:698:46: error: called object '0' is not a function drivers/usb/gadget/bcm63xx_udc.c:700:49: error: called object '0' is not a function Fix this by updating usb_dmac_{read,write}l and usb_dmas_{read,write}l to take an extra channel argument, and use the channel width (ENETDMA_CHAN_WIDTH) to offset the register we want to access, hence doing again what the macro implicitely did for us. Cc: Kevin Cernekee Cc: Jonas Gorski Signed-off-by: Florian Fainelli Signed-off-by: Felipe Balbi Signed-off-by: Greg Kroah-Hartman

usb: gadget: f_mass_storage: call try_to_freeze only when its safe

2013-11-25T17:34:09Z

Call try_to_freeze() in sleep_thread() only when it's safe to sleep. do_read() and do_write() calls sleep_thread with lock held. Make sure these won't call try_to_freeze() by passing can_freeze flag to sleep_thread. Calling try_to_freeze() with a lock hold was done since day one in f_mass_storage but since commit 0f9548ca1 ("lockdep: check that no locks held at freeze time") lockdep complains about it. Signed-off-by: George Cherian Acked-by: Sebastian Andrzej Siewior Acked-by: Alan Stern Signed-off-by: Felipe Balbi

usb: gadget: tcm_usb_gadget: mark bot_cleanup_old_alt static

2013-11-25T17:19:41Z

that symbol is only used inside this function driver, we should mark it static. Fixes sparse's: drivers/usb/gadget/tcm_usb_gadget.c:373:6: warning: symbol \ 'bot_cleanup_old_alt' was not declared. Should it \ be static? Signed-off-by: Felipe Balbi

usb: gadget: ffs: fix sparse warning

2013-11-25T17:16:49Z

use NULL instead of 0 as pointer. Signed-off-by: Felipe Balbi

usb: gadget: zero: module parameters can be static

2013-11-25T17:12:15Z

g_zero's module parameters can, and should, be static. This fixes sparse warnings. Cc: Peter Chen Signed-off-by: Fengguang Wu Signed-off-by: Felipe Balbi

usb: gadget: storage: fix sparse warning

2013-11-25T17:07:46Z

fsg_common_set_inquiry_string() expects pointers as second and third argument. Let's fix that by passing NULL instead of plain 0 just so we silence sparse's: drivers/usb/gadget/f_mass_storage.c:3114:60: warning: \ Using plain integer as NULL pointer drivers/usb/gadget/f_mass_storage.c:3114:63: warning: \ Using plain integer as NULL pointer Signed-off-by: Felipe Balbi

usb: gadget: mass storage: fix return of delayed status

2013-11-25T16:56:33Z

Mass storage gadget returns DELAYED_STATUS in stead of USB_GADGET_DELAYED_STATUS while handling bulk reset request. Since peripheral driver uses USB_GADGET_DELAYED_STATUS for delayed status handling, therefore replace DELAYED_STATUS by USB_GADGET_DELAYED_STATUS in mass storage driver. Since, DELAYED_STATUS and hence EP0_BUFSIZE will no longer be used now, so remove them. Signed-off-by: Pratyush Anand Cc: Paul Zimmerman Cc: Alan Stern Signed-off-by: Felipe Balbi

usb: gadget: f_mass_storage: fix mass storage dependency

2013-11-25T16:54:31Z

Legacy gadgets supporting mass storage (g_mass_storage, g_acm_ms, g_multi) all depend on BLOCK. Make the standalone compilation of f_mass_storage (without any legacy gadget) dependent no BLOCK, too. Signed-off-by: Andrzej Pietrasiewicz Signed-off-by: Kyungmin Park Signed-off-by: Felipe Balbi

usb: gadget: composite: reset delayed_status on reset_config

2013-11-25T16:54:17Z

The delayed_status value is used to keep track of status response packets on ep0. It needs to be reset or the set_config function would still delay the answer, if the usb device got unplugged while waiting for setup_continue to be called. Cc: stable@vger.kernel.org Signed-off-by: Michael Grzeschik Signed-off-by: Felipe Balbi