cregit-Linux how code gets into the kernel

Release 4.7 drivers/usb/musb/musbhsdma.c

Directory: drivers/usb/musb
/*
 * MUSB OTG driver - support for Mentor's DMA controller
 *
 * Copyright 2005 Mentor Graphics Corporation
 * Copyright (C) 2005-2007 by Texas Instruments
 *
 * This program is free software; you can redistribute it and/or
 * modify it under the terms of the GNU General Public License
 * version 2 as published by the Free Software Foundation.
 *
 * 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., 51 Franklin St, Fifth Floor, Boston, MA
 * 02110-1301 USA
 *
 * THIS SOFTWARE IS PROVIDED "AS IS" AND ANY EXPRESS OR IMPLIED
 * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF
 * MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.  IN
 * NO EVENT SHALL THE AUTHORS BE LIABLE FOR ANY DIRECT, INDIRECT,
 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF
 * USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON
 * ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 *
 */
#include <linux/device.h>
#include <linux/interrupt.h>
#include <linux/platform_device.h>
#include <linux/slab.h>
#include "musb_core.h"
#include "musbhsdma.h"

static void dma_channel_release(struct dma_channel *channel);


static void dma_controller_stop(struct musb_dma_controller *controller) { struct musb *musb = controller->private_data; struct dma_channel *channel; u8 bit; if (controller->used_channels != 0) { dev_err(musb->controller, "Stopping DMA controller while channel active\n"); for (bit = 0; bit < MUSB_HSDMA_CHANNELS; bit++) { if (controller->used_channels & (1 << bit)) { channel = &controller->channel[bit].channel; dma_channel_release(channel); if (!controller->used_channels) break; } } } }

Contributors

PersonTokensPropCommitsCommitProp
felipe balbifelipe balbi9897.03%266.67%
sebastian andrzej siewiorsebastian andrzej siewior32.97%133.33%
Total101100.00%3100.00%


static struct dma_channel *dma_channel_allocate(struct dma_controller *c, struct musb_hw_ep *hw_ep, u8 transmit) { struct musb_dma_controller *controller = container_of(c, struct musb_dma_controller, controller); struct musb_dma_channel *musb_channel = NULL; struct dma_channel *channel = NULL; u8 bit; for (bit = 0; bit < MUSB_HSDMA_CHANNELS; bit++) { if (!(controller->used_channels & (1 << bit))) { controller->used_channels |= (1 << bit); musb_channel = &(controller->channel[bit]); musb_channel->controller = controller; musb_channel->idx = bit; musb_channel->epnum = hw_ep->epnum; musb_channel->transmit = transmit; channel = &(musb_channel->channel); channel->private_data = musb_channel; channel->status = MUSB_DMA_STATUS_FREE; channel->max_len = 0x100000; /* Tx => mode 1; Rx => mode 0 */ channel->desired_mode = transmit; channel->actual_len = 0; break; } } return channel; }

Contributors

PersonTokensPropCommitsCommitProp
felipe balbifelipe balbi17699.44%266.67%
anil shettyanil shetty10.56%133.33%
Total177100.00%3100.00%


static void dma_channel_release(struct dma_channel *channel) { struct musb_dma_channel *musb_channel = channel->private_data; channel->actual_len = 0; musb_channel->start_addr = 0; musb_channel->len = 0; musb_channel->controller->used_channels &= ~(1 << musb_channel->idx); channel->status = MUSB_DMA_STATUS_UNKNOWN; }

Contributors

PersonTokensPropCommitsCommitProp
felipe balbifelipe balbi59100.00%2100.00%
Total59100.00%2100.00%


static void configure_channel(struct dma_channel *channel, u16 packet_sz, u8 mode, dma_addr_t dma_addr, u32 len) { struct musb_dma_channel *musb_channel = channel->private_data; struct musb_dma_controller *controller = musb_channel->controller; struct musb *musb = controller->private_data; void __iomem *mbase = controller->base; u8 bchannel = musb_channel->idx; u16 csr = 0; dev_dbg(musb->controller, "%p, pkt_sz %d, addr %pad, len %d, mode %d\n", channel, packet_sz, &dma_addr, len, mode); if (mode) { csr |= 1 << MUSB_HSDMA_MODE1_SHIFT; BUG_ON(len < packet_sz); } csr |= MUSB_HSDMA_BURSTMODE_INCR16 << MUSB_HSDMA_BURSTMODE_SHIFT; csr |= (musb_channel->epnum << MUSB_HSDMA_ENDPOINT_SHIFT) | (1 << MUSB_HSDMA_ENABLE_SHIFT) | (1 << MUSB_HSDMA_IRQENABLE_SHIFT) | (musb_channel->transmit ? (1 << MUSB_HSDMA_TRANSMIT_SHIFT) : 0); /* address/count */ musb_write_hsdma_addr(mbase, bchannel, dma_addr); musb_write_hsdma_count(mbase, bchannel, len); /* control (this should start things) */ musb_writew(mbase, MUSB_HSDMA_CHANNEL_OFFSET(bchannel, MUSB_HSDMA_CONTROL), csr); }

Contributors

PersonTokensPropCommitsCommitProp
felipe balbifelipe balbi18197.31%350.00%
bryan wubryan wu21.08%116.67%
arnd bergmannarnd bergmann21.08%116.67%
hema kalliguddihema kalliguddi10.54%116.67%
Total186100.00%6100.00%


static int dma_channel_program(struct dma_channel *channel, u16 packet_sz, u8 mode, dma_addr_t dma_addr, u32 len) { struct musb_dma_channel *musb_channel = channel->private_data; struct musb_dma_controller *controller = musb_channel->controller; struct musb *musb = controller->private_data; dev_dbg(musb->controller, "ep%d-%s pkt_sz %d, dma_addr %pad length %d, mode %d\n", musb_channel->epnum, musb_channel->transmit ? "Tx" : "Rx", packet_sz, &dma_addr, len, mode); BUG_ON(channel->status == MUSB_DMA_STATUS_UNKNOWN || channel->status == MUSB_DMA_STATUS_BUSY); /* Let targets check/tweak the arguments */ if (musb->ops->adjust_channel_params) { int ret = musb->ops->adjust_channel_params(channel, packet_sz, &mode, &dma_addr, &len); if (ret) return ret; } /* * The DMA engine in RTL1.8 and above cannot handle * DMA addresses that are not aligned to a 4 byte boundary. * It ends up masking the last two bits of the address * programmed in DMA_ADDR. * * Fail such DMA transfers, so that the backup PIO mode * can carry out the transfer */ if ((musb->hwvers >= MUSB_HWVERS_1800) && (dma_addr % 4)) return false; channel->actual_len = 0; musb_channel->start_addr = dma_addr; musb_channel->len = len; musb_channel->max_packet_sz = packet_sz; channel->status = MUSB_DMA_STATUS_BUSY; configure_channel(channel, packet_sz, mode, dma_addr, len); return true; }

Contributors

PersonTokensPropCommitsCommitProp
felipe balbifelipe balbi12059.41%342.86%
mike frysingermike frysinger4120.30%114.29%
anand gadiyaranand gadiyar3919.31%228.57%
arnd bergmannarnd bergmann20.99%114.29%
Total202100.00%7100.00%


static int dma_channel_abort(struct dma_channel *channel) { struct musb_dma_channel *musb_channel = channel->private_data; void __iomem *mbase = musb_channel->controller->base; struct musb *musb = musb_channel->controller->private_data; u8 bchannel = musb_channel->idx; int offset; u16 csr; if (channel->status == MUSB_DMA_STATUS_BUSY) { if (musb_channel->transmit) { offset = musb->io.ep_offset(musb_channel->epnum, MUSB_TXCSR); /* * The programming guide says that we must clear * the DMAENAB bit before the DMAMODE bit... */ csr = musb_readw(mbase, offset); csr &= ~(MUSB_TXCSR_AUTOSET | MUSB_TXCSR_DMAENAB); musb_writew(mbase, offset, csr); csr &= ~MUSB_TXCSR_DMAMODE; musb_writew(mbase, offset, csr); } else { offset = musb->io.ep_offset(musb_channel->epnum, MUSB_RXCSR); csr = musb_readw(mbase, offset); csr &= ~(MUSB_RXCSR_AUTOCLEAR | MUSB_RXCSR_DMAENAB | MUSB_RXCSR_DMAMODE); musb_writew(mbase, offset, csr); } musb_writew(mbase, MUSB_HSDMA_CHANNEL_OFFSET(bchannel, MUSB_HSDMA_CONTROL), 0); musb_write_hsdma_addr(mbase, bchannel, 0); musb_write_hsdma_count(mbase, bchannel, 0); channel->status = MUSB_DMA_STATUS_FREE; } return 0; }

Contributors

PersonTokensPropCommitsCommitProp
felipe balbifelipe balbi15972.94%240.00%
sergei shtylyovsergei shtylyov3616.51%120.00%
tony lindgrentony lindgren219.63%120.00%
bryan wubryan wu20.92%120.00%
Total218100.00%5100.00%


static irqreturn_t dma_controller_irq(int irq, void *private_data) { struct musb_dma_controller *controller = private_data; struct musb *musb = controller->private_data; struct musb_dma_channel *musb_channel; struct dma_channel *channel; void __iomem *mbase = controller->base; irqreturn_t retval = IRQ_NONE; unsigned long flags; u8 bchannel; u8 int_hsdma; u32 addr, count; u16 csr; spin_lock_irqsave(&musb->lock, flags); int_hsdma = musb_readb(mbase, MUSB_HSDMA_INTR); #ifdef CONFIG_BLACKFIN /* Clear DMA interrupt flags */ musb_writeb(mbase, MUSB_HSDMA_INTR, int_hsdma); #endif if (!int_hsdma) { dev_dbg(musb->controller, "spurious DMA irq\n"); for (bchannel = 0; bchannel < MUSB_HSDMA_CHANNELS; bchannel++) { musb_channel = (struct musb_dma_channel *) &(controller->channel[bchannel]); channel = &musb_channel->channel; if (channel->status == MUSB_DMA_STATUS_BUSY) { count = musb_read_hsdma_count(mbase, bchannel); if (count == 0) int_hsdma |= (1 << bchannel); } } dev_dbg(musb->controller, "int_hsdma = 0x%x\n", int_hsdma); if (!int_hsdma) goto done; } for (bchannel = 0; bchannel < MUSB_HSDMA_CHANNELS; bchannel++) { if (int_hsdma & (1 << bchannel)) { musb_channel = (struct musb_dma_channel *) &(controller->channel[bchannel]); channel = &musb_channel->channel; csr = musb_readw(mbase, MUSB_HSDMA_CHANNEL_OFFSET(bchannel, MUSB_HSDMA_CONTROL)); if (csr & (1 << MUSB_HSDMA_BUSERROR_SHIFT)) { musb_channel->channel.status = MUSB_DMA_STATUS_BUS_ABORT; } else { u8 devctl; addr = musb_read_hsdma_addr(mbase, bchannel); channel->actual_len = addr - musb_channel->start_addr; dev_dbg(musb->controller, "ch %p, 0x%x -> 0x%x (%zu / %d) %s\n", channel, musb_channel->start_addr, addr, channel->actual_len, musb_channel->len, (channel->actual_len < musb_channel->len) ? "=> reconfig 0" : "=> complete"); devctl = musb_readb(mbase, MUSB_DEVCTL); channel->status = MUSB_DMA_STATUS_FREE; /* completed */ if ((devctl & MUSB_DEVCTL_HM) && (musb_channel->transmit) && ((channel->desired_mode == 0) || (channel->actual_len & (musb_channel->max_packet_sz - 1))) ) { u8 epnum = musb_channel->epnum; int offset = musb->io.ep_offset(epnum, MUSB_TXCSR); u16 txcsr; /* * The programming guide says that we * must clear DMAENAB before DMAMODE. */ musb_ep_select(mbase, epnum); txcsr = musb_readw(mbase, offset); txcsr &= ~(MUSB_TXCSR_DMAENAB | MUSB_TXCSR_AUTOSET); musb_writew(mbase, offset, txcsr); /* Send out the packet */ txcsr &= ~MUSB_TXCSR_DMAMODE; txcsr |= MUSB_TXCSR_TXPKTRDY; musb_writew(mbase, offset, txcsr); } musb_dma_completion(musb, musb_channel->epnum, musb_channel->transmit); } } } retval = IRQ_HANDLED; done: spin_unlock_irqrestore(&musb->lock, flags); return retval; }

Contributors

PersonTokensPropCommitsCommitProp
felipe balbifelipe balbi34765.84%333.33%
anand gadiyaranand gadiyar10119.17%111.11%
sergei shtylyovsergei shtylyov5710.82%111.11%
cliff caicliff cai152.85%111.11%
tony lindgrentony lindgren50.95%111.11%
bryan wubryan wu10.19%111.11%
mike frysingermike frysinger10.19%111.11%
Total527100.00%9100.00%


void musbhs_dma_controller_destroy(struct dma_controller *c) { struct musb_dma_controller *controller = container_of(c, struct musb_dma_controller, controller); dma_controller_stop(controller); if (controller->irq) free_irq(controller->irq, c); kfree(controller); }

Contributors

PersonTokensPropCommitsCommitProp
felipe balbifelipe balbi4488.00%250.00%
sebastian andrzej siewiorsebastian andrzej siewior510.00%125.00%
tony lindgrentony lindgren12.00%125.00%
Total50100.00%4100.00%

EXPORT_SYMBOL_GPL(musbhs_dma_controller_destroy);
struct dma_controller *musbhs_dma_controller_create(struct musb *musb, void __iomem *base) { struct musb_dma_controller *controller; struct device *dev = musb->controller; struct platform_device *pdev = to_platform_device(dev); int irq = platform_get_irq_byname(pdev, "dma"); if (irq <= 0) { dev_err(dev, "No DMA interrupt line!\n"); return NULL; } controller = kzalloc(sizeof(*controller), GFP_KERNEL); if (!controller) return NULL; controller->channel_count = MUSB_HSDMA_CHANNELS; controller->private_data = musb; controller->base = base; controller->controller.channel_alloc = dma_channel_allocate; controller->controller.channel_release = dma_channel_release; controller->controller.channel_program = dma_channel_program; controller->controller.channel_abort = dma_channel_abort; if (request_irq(irq, dma_controller_irq, 0, dev_name(musb->controller), &controller->controller)) { dev_err(dev, "request_irq %d failed!\n", irq); musb_dma_controller_destroy(&controller->controller); return NULL; } controller->irq = irq; return &controller->controller; }

Contributors

PersonTokensPropCommitsCommitProp
felipe balbifelipe balbi18895.43%228.57%
kay sieverskay sievers31.52%114.29%
tony lindgrentony lindgren21.02%114.29%
hema kalliguddihema kalliguddi21.02%114.29%
sergei shtylyovsergei shtylyov10.51%114.29%
yong zhangyong zhang10.51%114.29%
Total197100.00%7100.00%

EXPORT_SYMBOL_GPL(musbhs_dma_controller_create);

Overall Contributors

PersonTokensPropCommitsCommitProp
felipe balbifelipe balbi139779.56%313.64%
anand gadiyaranand gadiyar1407.97%313.64%
sergei shtylyovsergei shtylyov945.35%29.09%
mike frysingermike frysinger422.39%29.09%
tony lindgrentony lindgren392.22%29.09%
cliff caicliff cai150.85%14.55%
sebastian andrzej siewiorsebastian andrzej siewior80.46%14.55%
bryan wubryan wu60.34%14.55%
arnd bergmannarnd bergmann40.23%14.55%
kay sieverskay sievers30.17%14.55%
tejun heotejun heo30.17%14.55%
hema kalliguddihema kalliguddi30.17%29.09%
anil shettyanil shetty10.06%14.55%
yong zhangyong zhang10.06%14.55%
Total1756100.00%22100.00%
Directory: drivers/usb/musb
Information contained on this website is for historical information purposes only and does not indicate or represent copyright ownership.
{% endraw %}