/* * Copyright (c) by Jaroslav Kysela * Copyright (c) 2009 by Krzysztof Helt * Routines for control of MPU-401 in UART mode * * MPU-401 supports UART mode which is not capable generate transmit * interrupts thus output is done via polling. Also, if irq < 0, then * input is done also via polling. Do not expect good performance. * * * This program is free software; you can redistribute it and/or modify * it under the terms of the GNU General Public License as published by * the Free Software Foundation; either version 2 of the License, or * (at your option) any later version. * * This program is distributed in the hope that it will be useful, * but WITHOUT ANY WARRANTY; without even the implied warranty of * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the * GNU General Public License for more details. * * You should have received a copy of the GNU General Public License * along with this program; if not, write to the Free Software * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA * */ #include #include #include #include #include #include #include #include #include "msnd.h" #define MSNDMIDI_MODE_BIT_INPUT 0 #define MSNDMIDI_MODE_BIT_OUTPUT 1 #define MSNDMIDI_MODE_BIT_INPUT_TRIGGER 2 #define MSNDMIDI_MODE_BIT_OUTPUT_TRIGGER 3 struct snd_msndmidi { struct snd_msnd *dev; unsigned long mode; /* MSNDMIDI_MODE_XXXX */ struct snd_rawmidi_substream *substream_input; spinlock_t input_lock; }; /* * input/output open/close - protected by open_mutex in rawmidi.c */ static int snd_msndmidi_input_open(struct snd_rawmidi_substream *substream) { struct snd_msndmidi *mpu; snd_printdd("snd_msndmidi_input_open()\n"); mpu = substream->rmidi->private_data; mpu->substream_input = substream; snd_msnd_enable_irq(mpu->dev); snd_msnd_send_dsp_cmd(mpu->dev, HDEX_MIDI_IN_START); set_bit(MSNDMIDI_MODE_BIT_INPUT, &mpu->mode); return 0; } static int snd_msndmidi_input_close(struct snd_rawmidi_substream *substream) { struct snd_msndmidi *mpu; mpu = substream->rmidi->private_data; snd_msnd_send_dsp_cmd(mpu->dev, HDEX_MIDI_IN_STOP); clear_bit(MSNDMIDI_MODE_BIT_INPUT, &mpu->mode); mpu->substream_input = NULL; snd_msnd_disable_irq(mpu->dev); return 0; } static void snd_msndmidi_input_drop(struct snd_msndmidi *mpu) { u16 tail; tail = readw(mpu->dev->MIDQ + JQS_wTail); writew(tail, mpu->dev->MIDQ + JQS_wHead); } /* * trigger input */ static void snd_msndmidi_input_trigger(struct snd_rawmidi_substream *substream, int up) { unsigned long flags; struct snd_msndmidi *mpu; snd_printdd("snd_msndmidi_input_trigger(, %i)\n", up); mpu = substream->rmidi->private_data; spin_lock_irqsave(&mpu->input_lock, flags); if (up) { if (!test_and_set_bit(MSNDMIDI_MODE_BIT_INPUT_TRIGGER, &mpu->mode)) snd_msndmidi_input_drop(mpu); } else { clear_bit(MSNDMIDI_MODE_BIT_INPUT_TRIGGER, &mpu->mode); } spin_unlock_irqrestore(&mpu->input_lock, flags); if (up) snd_msndmidi_input_read(mpu); } void snd_msndmidi_input_read(void *mpuv) { unsigned long flags; struct snd_msndmidi *mpu = mpuv; void *pwMIDQData = mpu->dev->mappedbase + MIDQ_DATA_BUFF; spin_lock_irqsave(&mpu->input_lock, flags); while (readw(mpu->dev->MIDQ + JQS_wTail) != readw(mpu->dev->MIDQ + JQS_wHead)) { u16 wTmp, val; val = readw(pwMIDQData + 2 * readw(mpu->dev->MIDQ + JQS_wHead)); if (test_bit(MSNDMIDI_MODE_BIT_INPUT_TRIGGER, &mpu->mode)) snd_rawmidi_receive(mpu->substream_input, (unsigned char *)&val, 1); wTmp = readw(mpu->dev->MIDQ + JQS_wHead) + 1; if (wTmp > readw(mpu->dev->MIDQ + JQS_wSize)) writew(0, mpu->dev->MIDQ + JQS_wHead); else writew(wTmp, mpu->dev->MIDQ + JQS_wHead); } spin_unlock_irqrestore(&mpu->input_lock, flags); } EXPORT_SYMBOL(snd_msndmidi_input_read); static struct snd_rawmidi_ops snd_msndmidi_input = { .open = snd_msndmidi_input_open, .close = snd_msndmidi_input_close, .trigger = snd_msndmidi_input_trigger, }; static void snd_msndmidi_free(struct snd_rawmidi *rmidi) { struct snd_msndmidi *mpu = rmidi->private_data; kfree(mpu); } int snd_msndmidi_new(struct snd_card *card, int device) { struct snd_msnd *chip = card->private_data; struct snd_msndmidi *mpu; struct snd_rawmidi *rmidi; int err; err = snd_rawmidi_new(card, "MSND-MIDI", device, 1, 1, &rmidi); if (err < 0) return err; mpu = kzalloc(sizeof(*mpu), GFP_KERNEL); if (mpu == NULL) { snd_device_free(card, rmidi); return -ENOMEM; } mpu->dev = chip; chip->msndmidi_mpu = mpu; rmidi->private_data = mpu; rmidi->private_free = snd_msndmidi_free; spin_lock_init(&mpu->input_lock); strcpy(rmidi->name, "MSND MIDI"); snd_rawmidi_set_ops(rmidi, SNDRV_RAWMIDI_STREAM_INPUT, &snd_msndmidi_input); rmidi->info_flags |= SNDRV_RAWMIDI_INFO_INPUT; return 0; } .git/patch/sound/isa/als100.c?id=433e19cf33d34bb6751c874a9c00980552fe508c'>patch) treece6547ef2987fbb289fa28f03536328a42781651 /sound/isa/als100.c parent191e885a2e130e639bb0c8ee350d7047294f2ce6 (diff)
Drivers: hv: vmbus: finally fix hv_need_to_signal_on_read()
Commit a389fcfd2cb5 ("Drivers: hv: vmbus: Fix signaling logic in hv_need_to_signal_on_read()") added the proper mb(), but removed the test "prev_write_sz < pending_sz" when making the signal decision. As a result, the guest can signal the host unnecessarily, and then the host can throttle the guest because the host thinks the guest is buggy or malicious; finally the user running stress test can perceive intermittent freeze of the guest. This patch brings back the test, and properly handles the in-place consumption APIs used by NetVSC (see get_next_pkt_raw(), put_pkt_raw() and commit_rd_index()). Fixes: a389fcfd2cb5 ("Drivers: hv: vmbus: Fix signaling logic in hv_need_to_signal_on_read()") Signed-off-by: Dexuan Cui <decui@microsoft.com> Reported-by: Rolf Neugebauer <rolf.neugebauer@docker.com> Tested-by: Rolf Neugebauer <rolf.neugebauer@docker.com> Cc: "K. Y. Srinivasan" <kys@microsoft.com> Cc: Haiyang Zhang <haiyangz@microsoft.com> Cc: Stephen Hemminger <sthemmin@microsoft.com> Cc: <stable@vger.kernel.org> Signed-off-by: K. Y. Srinivasan <kys@microsoft.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Diffstat (limited to 'sound/isa/als100.c')