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Release 4.15 drivers/usb/musb/tusb6010_omap.c

Directory: drivers/usb/musb
// SPDX-License-Identifier: GPL-2.0
/*
 * TUSB6010 USB 2.0 OTG Dual Role controller OMAP DMA interface
 *
 * Copyright (C) 2006 Nokia Corporation
 * Tony Lindgren <tony@atomide.com>
 */
#include <linux/module.h>
#include <linux/kernel.h>
#include <linux/errno.h>
#include <linux/usb.h>
#include <linux/platform_device.h>
#include <linux/dma-mapping.h>
#include <linux/slab.h>
#include <linux/dmaengine.h>

#include "musb_core.h"
#include "tusb6010.h"


#define to_chdat(c)		((struct tusb_omap_dma_ch *)(c)->private_data)


#define MAX_DMAREQ		5	
/* REVISIT: Really 6, but req5 not OK */


struct tusb_dma_data {
	
s8			dmareq;
	
struct dma_chan		*chan;
};


struct tusb_omap_dma_ch {
	
struct musb		*musb;
	
void __iomem		*tbase;
	
unsigned long		phys_offset;
	
int			epnum;
	
u8			tx;
	
struct musb_hw_ep	*hw_ep;

	
struct tusb_dma_data	*dma_data;

	
struct tusb_omap_dma	*tusb_dma;

	
dma_addr_t		dma_addr;

	
u32			len;
	
u16			packet_sz;
	
u16			transfer_packet_sz;
	
u32			transfer_len;
	
u32			completed_len;
};


struct tusb_omap_dma {
	
struct dma_controller		controller;
	
void __iomem			*tbase;

	
struct tusb_dma_data		dma_pool[MAX_DMAREQ];
	
unsigned			multichannel:1;
};

/*
 * Allocate dmareq0 to the current channel unless it's already taken
 */

static inline int tusb_omap_use_shared_dmareq(struct tusb_omap_dma_ch *chdat) { u32 reg = musb_readl(chdat->tbase, TUSB_DMA_EP_MAP); if (reg != 0) { dev_dbg(chdat->musb->controller, "ep%i dmareq0 is busy for ep%i\n", chdat->epnum, reg & 0xf); return -EAGAIN; } if (chdat->tx) reg = (1 << 4) | chdat->epnum; else reg = chdat->epnum; musb_writel(chdat->tbase, TUSB_DMA_EP_MAP, reg); return 0; }

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Felipe Balbi9297.87%266.67%
Sergei Trofimovich22.13%133.33%
Total94100.00%3100.00%


static inline void tusb_omap_free_shared_dmareq(struct tusb_omap_dma_ch *chdat) { u32 reg = musb_readl(chdat->tbase, TUSB_DMA_EP_MAP); if ((reg & 0xf) != chdat->epnum) { printk(KERN_ERR "ep%i trying to release dmareq0 for ep%i\n", chdat->epnum, reg & 0xf); return; } musb_writel(chdat->tbase, TUSB_DMA_EP_MAP, 0); }

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Felipe Balbi64100.00%1100.00%
Total64100.00%1100.00%

/* * See also musb_dma_completion in plat_uds.c and musb_g_[tx|rx]() in * musb_gadget.c. */
static void tusb_omap_dma_cb(void *data) { struct dma_channel *channel = (struct dma_channel *)data; struct tusb_omap_dma_ch *chdat = to_chdat(channel); struct tusb_omap_dma *tusb_dma = chdat->tusb_dma; struct musb *musb = chdat->musb; struct device *dev = musb->controller; struct musb_hw_ep *hw_ep = chdat->hw_ep; void __iomem *ep_conf = hw_ep->conf; void __iomem *mbase = musb->mregs; unsigned long remaining, flags, pio; spin_lock_irqsave(&musb->lock, flags); dev_dbg(musb->controller, "ep%i %s dma callback\n", chdat->epnum, chdat->tx ? "tx" : "rx"); if (chdat->tx) remaining = musb_readl(ep_conf, TUSB_EP_TX_OFFSET); else remaining = musb_readl(ep_conf, TUSB_EP_RX_OFFSET); remaining = TUSB_EP_CONFIG_XFR_SIZE(remaining); /* HW issue #10: XFR_SIZE may get corrupt on DMA (both async & sync) */ if (unlikely(remaining > chdat->transfer_len)) { dev_dbg(musb->controller, "Corrupt %s XFR_SIZE: 0x%08lx\n", chdat->tx ? "tx" : "rx", remaining); remaining = 0; } channel->actual_len = chdat->transfer_len - remaining; pio = chdat->len - channel->actual_len; dev_dbg(musb->controller, "DMA remaining %lu/%u\n", remaining, chdat->transfer_len); /* Transfer remaining 1 - 31 bytes */ if (pio > 0 && pio < 32) { u8 *buf; dev_dbg(musb->controller, "Using PIO for remaining %lu bytes\n", pio); buf = phys_to_virt((u32)chdat->dma_addr) + chdat->transfer_len; if (chdat->tx) { dma_unmap_single(dev, chdat->dma_addr, chdat->transfer_len, DMA_TO_DEVICE); musb_write_fifo(hw_ep, pio, buf); } else { dma_unmap_single(dev, chdat->dma_addr, chdat->transfer_len, DMA_FROM_DEVICE); musb_read_fifo(hw_ep, pio, buf); } channel->actual_len += pio; } if (!tusb_dma->multichannel) tusb_omap_free_shared_dmareq(chdat); channel->status = MUSB_DMA_STATUS_FREE; musb_dma_completion(musb, chdat->epnum, chdat->tx); /* We must terminate short tx transfers manually by setting TXPKTRDY. * REVISIT: This same problem may occur with other MUSB dma as well. * Easy to test with g_ether by pinging the MUSB board with ping -s54. */ if ((chdat->transfer_len < chdat->packet_sz) || (chdat->transfer_len % chdat->packet_sz != 0)) { u16 csr; if (chdat->tx) { dev_dbg(musb->controller, "terminating short tx packet\n"); musb_ep_select(mbase, chdat->epnum); csr = musb_readw(hw_ep->regs, MUSB_TXCSR); csr |= MUSB_TXCSR_MODE | MUSB_TXCSR_TXPKTRDY | MUSB_TXCSR_P_WZC_BITS; musb_writew(hw_ep->regs, MUSB_TXCSR, csr); } } spin_unlock_irqrestore(&musb->lock, flags); }

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Felipe Balbi44094.62%250.00%
Tony Lindgren234.95%125.00%
Peter Ujfalusi20.43%125.00%
Total465100.00%4100.00%


static int tusb_omap_dma_program(struct dma_channel *channel, u16 packet_sz, u8 rndis_mode, dma_addr_t dma_addr, u32 len) { struct tusb_omap_dma_ch *chdat = to_chdat(channel); struct tusb_omap_dma *tusb_dma = chdat->tusb_dma; struct musb *musb = chdat->musb; struct device *dev = musb->controller; struct musb_hw_ep *hw_ep = chdat->hw_ep; void __iomem *mbase = musb->mregs; void __iomem *ep_conf = hw_ep->conf; dma_addr_t fifo_addr = hw_ep->fifo_sync; u32 dma_remaining; u16 csr; u32 psize; struct tusb_dma_data *dma_data; struct dma_async_tx_descriptor *dma_desc; struct dma_slave_config dma_cfg; enum dma_transfer_direction dma_dir; u32 port_window; int ret; if (unlikely(dma_addr & 0x1) || (len < 32) || (len > packet_sz)) return false; /* * HW issue #10: Async dma will eventually corrupt the XFR_SIZE * register which will cause missed DMA interrupt. We could try to * use a timer for the callback, but it is unsafe as the XFR_SIZE * register is corrupt, and we won't know if the DMA worked. */ if (dma_addr & 0x2) return false; /* * Because of HW issue #10, it seems like mixing sync DMA and async * PIO access can confuse the DMA. Make sure XFR_SIZE is reset before * using the channel for DMA. */ if (chdat->tx) dma_remaining = musb_readl(ep_conf, TUSB_EP_TX_OFFSET); else dma_remaining = musb_readl(ep_conf, TUSB_EP_RX_OFFSET); dma_remaining = TUSB_EP_CONFIG_XFR_SIZE(dma_remaining); if (dma_remaining) { dev_dbg(musb->controller, "Busy %s dma, not using: %08x\n", chdat->tx ? "tx" : "rx", dma_remaining); return false; } chdat->transfer_len = len & ~0x1f; if (len < packet_sz) chdat->transfer_packet_sz = chdat->transfer_len; else chdat->transfer_packet_sz = packet_sz; dma_data = chdat->dma_data; if (!tusb_dma->multichannel) { if (tusb_omap_use_shared_dmareq(chdat) != 0) { dev_dbg(musb->controller, "could not get dma for ep%i\n", chdat->epnum); return false; } if (dma_data->dmareq < 0) { /* REVISIT: This should get blocked earlier, happens * with MSC ErrorRecoveryTest */ WARN_ON(1); return false; } } chdat->packet_sz = packet_sz; chdat->len = len; channel->actual_len = 0; chdat->dma_addr = dma_addr; channel->status = MUSB_DMA_STATUS_BUSY; /* Since we're recycling dma areas, we need to clean or invalidate */ if (chdat->tx) { dma_dir = DMA_MEM_TO_DEV; dma_map_single(dev, phys_to_virt(dma_addr), len, DMA_TO_DEVICE); } else { dma_dir = DMA_DEV_TO_MEM; dma_map_single(dev, phys_to_virt(dma_addr), len, DMA_FROM_DEVICE); } memset(&dma_cfg, 0, sizeof(dma_cfg)); /* Use 16-bit transfer if dma_addr is not 32-bit aligned */ if ((dma_addr & 0x3) == 0) { dma_cfg.src_addr_width = DMA_SLAVE_BUSWIDTH_4_BYTES; dma_cfg.dst_addr_width = DMA_SLAVE_BUSWIDTH_4_BYTES; port_window = 8; } else { dma_cfg.src_addr_width = DMA_SLAVE_BUSWIDTH_2_BYTES; dma_cfg.dst_addr_width = DMA_SLAVE_BUSWIDTH_2_BYTES; port_window = 16; fifo_addr = hw_ep->fifo_async; } dev_dbg(musb->controller, "ep%i %s dma: %pad len: %u(%u) packet_sz: %i(%i)\n", chdat->epnum, chdat->tx ? "tx" : "rx", &dma_addr, chdat->transfer_len, len, chdat->transfer_packet_sz, packet_sz); dma_cfg.src_addr = fifo_addr; dma_cfg.dst_addr = fifo_addr; dma_cfg.src_port_window_size = port_window; dma_cfg.src_maxburst = port_window; dma_cfg.dst_port_window_size = port_window; dma_cfg.dst_maxburst = port_window; ret = dmaengine_slave_config(dma_data->chan, &dma_cfg); if (ret) { dev_err(musb->controller, "DMA slave config failed: %d\n", ret); return false; } dma_desc = dmaengine_prep_slave_single(dma_data->chan, dma_addr, chdat->transfer_len, dma_dir, DMA_PREP_INTERRUPT | DMA_CTRL_ACK); if (!dma_desc) { dev_err(musb->controller, "DMA prep_slave_single failed\n"); return false; } dma_desc->callback = tusb_omap_dma_cb; dma_desc->callback_param = channel; dmaengine_submit(dma_desc); dev_dbg(musb->controller, "ep%i %s using %i-bit %s dma from %pad to %pad\n", chdat->epnum, chdat->tx ? "tx" : "rx", dma_cfg.src_addr_width * 8, ((dma_addr & 0x3) == 0) ? "sync" : "async", (dma_dir == DMA_MEM_TO_DEV) ? &dma_addr : &fifo_addr, (dma_dir == DMA_MEM_TO_DEV) ? &fifo_addr : &dma_addr); /* * Prepare MUSB for DMA transfer */ musb_ep_select(mbase, chdat->epnum); if (chdat->tx) { csr = musb_readw(hw_ep->regs, MUSB_TXCSR); csr |= (MUSB_TXCSR_AUTOSET | MUSB_TXCSR_DMAENAB | MUSB_TXCSR_DMAMODE | MUSB_TXCSR_MODE); csr &= ~MUSB_TXCSR_P_UNDERRUN; musb_writew(hw_ep->regs, MUSB_TXCSR, csr); } else { csr = musb_readw(hw_ep->regs, MUSB_RXCSR); csr |= MUSB_RXCSR_DMAENAB; csr &= ~(MUSB_RXCSR_AUTOCLEAR | MUSB_RXCSR_DMAMODE); musb_writew(hw_ep->regs, MUSB_RXCSR, csr | MUSB_RXCSR_P_WZC_BITS); } /* Start DMA transfer */ dma_async_issue_pending(dma_data->chan); if (chdat->tx) { /* Send transfer_packet_sz packets at a time */ psize = musb_readl(ep_conf, TUSB_EP_MAX_PACKET_SIZE_OFFSET); psize &= ~0x7ff; psize |= chdat->transfer_packet_sz; musb_writel(ep_conf, TUSB_EP_MAX_PACKET_SIZE_OFFSET, psize); musb_writel(ep_conf, TUSB_EP_TX_OFFSET, TUSB_EP_CONFIG_XFR_SIZE(chdat->transfer_len)); } else { /* Receive transfer_packet_sz packets at a time */ psize = musb_readl(ep_conf, TUSB_EP_MAX_PACKET_SIZE_OFFSET); psize &= ~(0x7ff << 16); psize |= (chdat->transfer_packet_sz << 16); musb_writel(ep_conf, TUSB_EP_MAX_PACKET_SIZE_OFFSET, psize); musb_writel(ep_conf, TUSB_EP_RX_OFFSET, TUSB_EP_CONFIG_XFR_SIZE(chdat->transfer_len)); } return true; }

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PersonTokensPropCommitsCommitProp
Felipe Balbi61868.74%222.22%
Peter Ujfalusi26529.48%555.56%
Tony Lindgren151.67%111.11%
Arnd Bergmann10.11%111.11%
Total899100.00%9100.00%


static int tusb_omap_dma_abort(struct dma_channel *channel) { struct tusb_omap_dma_ch *chdat = to_chdat(channel); if (chdat->dma_data) dmaengine_terminate_all(chdat->dma_data->chan); channel->status = MUSB_DMA_STATUS_FREE; return 0; }

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Felipe Balbi3986.67%125.00%
Peter Ujfalusi613.33%375.00%
Total45100.00%4100.00%


static inline int tusb_omap_dma_allocate_dmareq(struct tusb_omap_dma_ch *chdat) { u32 reg = musb_readl(chdat->tbase, TUSB_DMA_EP_MAP); int i, dmareq_nr = -1; for (i = 0; i < MAX_DMAREQ; i++) { int cur = (reg & (0xf << (i * 5))) >> (i * 5); if (cur == 0) { dmareq_nr = i; break; } } if (dmareq_nr == -1) return -EAGAIN; reg |= (chdat->epnum << (dmareq_nr * 5)); if (chdat->tx) reg |= ((1 << 4) << (dmareq_nr * 5)); musb_writel(chdat->tbase, TUSB_DMA_EP_MAP, reg); chdat->dma_data = &chdat->tusb_dma->dma_pool[dmareq_nr]; return 0; }

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Felipe Balbi15296.20%133.33%
Peter Ujfalusi63.80%266.67%
Total158100.00%3100.00%


static inline void tusb_omap_dma_free_dmareq(struct tusb_omap_dma_ch *chdat) { u32 reg; if (!chdat || !chdat->dma_data || chdat->dma_data->dmareq < 0) return; reg = musb_readl(chdat->tbase, TUSB_DMA_EP_MAP); reg &= ~(0x1f << (chdat->dma_data->dmareq * 5)); musb_writel(chdat->tbase, TUSB_DMA_EP_MAP, reg); chdat->dma_data = NULL; }

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Felipe Balbi6886.08%133.33%
Peter Ujfalusi1113.92%266.67%
Total79100.00%3100.00%

static struct dma_channel *dma_channel_pool[MAX_DMAREQ];
static struct dma_channel * tusb_omap_dma_allocate(struct dma_controller *c, struct musb_hw_ep *hw_ep, u8 tx) { int ret, i; struct tusb_omap_dma *tusb_dma; struct musb *musb; struct dma_channel *channel = NULL; struct tusb_omap_dma_ch *chdat = NULL; struct tusb_dma_data *dma_data = NULL; tusb_dma = container_of(c, struct tusb_omap_dma, controller); musb = tusb_dma->controller.musb; /* REVISIT: Why does dmareq5 not work? */ if (hw_ep->epnum == 0) { dev_dbg(musb->controller, "Not allowing DMA for ep0 %s\n", tx ? "tx" : "rx"); return NULL; } for (i = 0; i < MAX_DMAREQ; i++) { struct dma_channel *ch = dma_channel_pool[i]; if (ch->status == MUSB_DMA_STATUS_UNKNOWN) { ch->status = MUSB_DMA_STATUS_FREE; channel = ch; chdat = ch->private_data; break; } } if (!channel) return NULL; chdat->musb = tusb_dma->controller.musb; chdat->tbase = tusb_dma->tbase; chdat->hw_ep = hw_ep; chdat->epnum = hw_ep->epnum; chdat->completed_len = 0; chdat->tusb_dma = tusb_dma; if (tx) chdat->tx = 1; else chdat->tx = 0; channel->max_len = 0x7fffffff; channel->desired_mode = 0; channel->actual_len = 0; if (!chdat->dma_data) { if (tusb_dma->multichannel) { ret = tusb_omap_dma_allocate_dmareq(chdat); if (ret != 0) goto free_dmareq; } else { chdat->dma_data = &tusb_dma->dma_pool[0]; } } dma_data = chdat->dma_data; dev_dbg(musb->controller, "ep%i %s dma: %s dmareq%i\n", chdat->epnum, chdat->tx ? "tx" : "rx", tusb_dma->multichannel ? "shared" : "dedicated", dma_data->dmareq); return channel; free_dmareq: tusb_omap_dma_free_dmareq(chdat); dev_dbg(musb->controller, "ep%i: Could not get a DMA channel\n", chdat->epnum); channel->status = MUSB_DMA_STATUS_UNKNOWN; return NULL; }

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Felipe Balbi30383.24%233.33%
Peter Ujfalusi5715.66%350.00%
Alexandre Bailon41.10%116.67%
Total364100.00%6100.00%


static void tusb_omap_dma_release(struct dma_channel *channel) { struct tusb_omap_dma_ch *chdat = to_chdat(channel); struct musb *musb = chdat->musb; dev_dbg(musb->controller, "Release for ep%i\n", chdat->epnum); channel->status = MUSB_DMA_STATUS_UNKNOWN; dmaengine_terminate_sync(chdat->dma_data->chan); tusb_omap_dma_free_dmareq(chdat); channel = NULL; }

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Felipe Balbi6394.03%250.00%
Peter Ujfalusi45.97%250.00%
Total67100.00%4100.00%


void tusb_dma_controller_destroy(struct dma_controller *c) { struct tusb_omap_dma *tusb_dma; int i; tusb_dma = container_of(c, struct tusb_omap_dma, controller); for (i = 0; i < MAX_DMAREQ; i++) { struct dma_channel *ch = dma_channel_pool[i]; if (ch) { kfree(ch->private_data); kfree(ch); } /* Free up the DMA channels */ if (tusb_dma && tusb_dma->dma_pool[i].chan) dma_release_channel(tusb_dma->dma_pool[i].chan); } kfree(tusb_dma); }

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Felipe Balbi8682.69%116.67%
Peter Ujfalusi1514.42%350.00%
Roel Kluin21.92%116.67%
Tony Lindgren10.96%116.67%
Total104100.00%6100.00%

EXPORT_SYMBOL_GPL(tusb_dma_controller_destroy);
static int tusb_omap_allocate_dma_pool(struct tusb_omap_dma *tusb_dma) { struct musb *musb = tusb_dma->controller.musb; int i; int ret = 0; for (i = 0; i < MAX_DMAREQ; i++) { struct tusb_dma_data *dma_data = &tusb_dma->dma_pool[i]; /* * Request DMA channels: * - one channel in case of non multichannel mode * - MAX_DMAREQ number of channels in multichannel mode */ if (i == 0 || tusb_dma->multichannel) { char ch_name[8]; sprintf(ch_name, "dmareq%d", i); dma_data->chan = dma_request_chan(musb->controller, ch_name); if (IS_ERR(dma_data->chan)) { dev_err(musb->controller, "Failed to request %s\n", ch_name); ret = PTR_ERR(dma_data->chan); goto dma_error; } dma_data->dmareq = i; } else { dma_data->dmareq = -1; } } return 0; dma_error: for (; i >= 0; i--) { struct tusb_dma_data *dma_data = &tusb_dma->dma_pool[i]; if (dma_data->dmareq >= 0) dma_release_channel(dma_data->chan); } return ret; }

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Peter Ujfalusi197100.00%2100.00%
Total197100.00%2100.00%


struct dma_controller * tusb_dma_controller_create(struct musb *musb, void __iomem *base) { void __iomem *tbase = musb->ctrl_base; struct tusb_omap_dma *tusb_dma; int i; /* REVISIT: Get dmareq lines used from board-*.c */ musb_writel(musb->ctrl_base, TUSB_DMA_INT_MASK, 0x7fffffff); musb_writel(musb->ctrl_base, TUSB_DMA_EP_MAP, 0); musb_writel(tbase, TUSB_DMA_REQ_CONF, TUSB_DMA_REQ_CONF_BURST_SIZE(2) | TUSB_DMA_REQ_CONF_DMA_REQ_EN(0x3f) | TUSB_DMA_REQ_CONF_DMA_REQ_ASSER(2)); tusb_dma = kzalloc(sizeof(struct tusb_omap_dma), GFP_KERNEL); if (!tusb_dma) goto out; tusb_dma->controller.musb = musb; tusb_dma->tbase = musb->ctrl_base; tusb_dma->controller.channel_alloc = tusb_omap_dma_allocate; tusb_dma->controller.channel_release = tusb_omap_dma_release; tusb_dma->controller.channel_program = tusb_omap_dma_program; tusb_dma->controller.channel_abort = tusb_omap_dma_abort; if (musb->tusb_revision >= TUSB_REV_30) tusb_dma->multichannel = 1; for (i = 0; i < MAX_DMAREQ; i++) { struct dma_channel *ch; struct tusb_omap_dma_ch *chdat; ch = kzalloc(sizeof(struct dma_channel), GFP_KERNEL); if (!ch) goto cleanup; dma_channel_pool[i] = ch; chdat = kzalloc(sizeof(struct tusb_omap_dma_ch), GFP_KERNEL); if (!chdat) goto cleanup; ch->status = MUSB_DMA_STATUS_UNKNOWN; ch->private_data = chdat; } if (tusb_omap_allocate_dma_pool(tusb_dma)) goto cleanup; return &tusb_dma->controller; cleanup: musb_dma_controller_destroy(&tusb_dma->controller); out: return NULL; }

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Felipe Balbi26093.19%116.67%
Peter Ujfalusi103.58%116.67%
Huzaifa Sidhpurwala31.08%116.67%
Matwey V. Kornilov20.72%116.67%
Tony Lindgren20.72%116.67%
Alexandre Bailon20.72%116.67%
Total279100.00%6100.00%

EXPORT_SYMBOL_GPL(tusb_dma_controller_create);

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PersonTokensPropCommitsCommitProp
Felipe Balbi230777.49%315.79%
Peter Ujfalusi59720.05%526.32%
Tony Lindgren521.75%210.53%
Alexandre Bailon60.20%15.26%
Huzaifa Sidhpurwala30.10%15.26%
Tejun Heo30.10%15.26%
Roel Kluin20.07%15.26%
Greg Kroah-Hartman20.07%210.53%
Matwey V. Kornilov20.07%15.26%
Sergei Trofimovich20.07%15.26%
Arnd Bergmann10.03%15.26%
Total2977100.00%19100.00%
Directory: drivers/usb/musb
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