Commit d0cc3d41 authored by Martin Fuzzey's avatar Martin Fuzzey Committed by Greg Kroah-Hartman
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USB: imx21-hcd accept arbitary transfer buffer alignement. 



The hardware can only do DMA to 4 byte aligned addresses.
When this requirement is not met use PIO or a bounce buffer.

PIO is used when the buffer is small enough to directly
use the hardware data memory (2*maxpacket).

A bounce buffer is used for larger transfers.

Signed-off-by: default avatarMartin Fuzzey <mfuzzey@gmail.com>
Signed-off-by: default avatarGreg Kroah-Hartman <gregkh@suse.de>
parent 1dae423d

drivers/usb/host/imx21-hcd.c

+163 −33
Original line number Diff line number Diff line
@@ -57,6 +57,7 @@ 
#include <linux/slab.h>

#include <linux/usb.h>

#include <linux/usb/hcd.h>

#include <linux/dma-mapping.h>



#include "imx21-hcd.h"
@@ -136,9 +137,18 @@ static int imx21_hc_get_frame(struct usb_hcd *hcd) 
	return wrap_frame(readl(imx21->regs + USBH_FRMNUB));

}



static inline bool unsuitable_for_dma(dma_addr_t addr)

{

	return (addr & 3) != 0;

}



#include "imx21-dbg.c"



static void nonisoc_urb_completed_for_etd(

	struct imx21 *imx21, struct etd_priv *etd, int status);

static void schedule_nonisoc_etd(struct imx21 *imx21, struct urb *urb);

static void free_dmem(struct imx21 *imx21, struct etd_priv *etd);



/* =========================================== */

/* ETD management				*/

/* ===========================================	*/
@@ -185,7 +195,8 @@ static void reset_etd(struct imx21 *imx21, int num) 
		etd_writel(imx21, num, i, 0);

	etd->urb = NULL;

	etd->ep = NULL;

	etd->td = NULL;;

	etd->td = NULL;

	etd->bounce_buffer = NULL;

}



static void free_etd(struct imx21 *imx21, int num)
@@ -221,26 +232,94 @@ static void setup_etd_dword0(struct imx21 *imx21, 
		((u32) maxpacket << DW0_MAXPKTSIZ));

}



static void activate_etd(struct imx21 *imx21,

	int etd_num, dma_addr_t dma, u8 dir)

/**

 * Copy buffer to data controller data memory.

 * We cannot use memcpy_toio() because the hardware requires 32bit writes

 */

static void copy_to_dmem(

	struct imx21 *imx21, int dmem_offset, void *src, int count)

{

	void __iomem *dmem = imx21->regs + USBOTG_DMEM + dmem_offset;

	u32 word = 0;

	u8 *p = src;

	int byte = 0;

	int i;



	for (i = 0; i < count; i++) {

		byte = i % 4;

		word += (*p++ << (byte * 8));

		if (byte == 3) {

			writel(word, dmem);

			dmem += 4;

			word = 0;

		}

	}



	if (count && byte != 3)

		writel(word, dmem);

}



static void activate_etd(struct imx21 *imx21, int etd_num, u8 dir)

{

	u32 etd_mask = 1 << etd_num;

	struct etd_priv *etd = &imx21->etd[etd_num];



	if (etd->dma_handle && unsuitable_for_dma(etd->dma_handle)) {

		/* For non aligned isoc the condition below is always true */

		if (etd->len <= etd->dmem_size) {

			/* Fits into data memory, use PIO */

			if (dir != TD_DIR_IN) {

				copy_to_dmem(imx21,

						etd->dmem_offset,

						etd->cpu_buffer, etd->len);

			}

			etd->dma_handle = 0;



		} else {

			/* Too big for data memory, use bounce buffer */

			enum dma_data_direction dmadir;



			if (dir == TD_DIR_IN) {

				dmadir = DMA_FROM_DEVICE;

				etd->bounce_buffer = kmalloc(etd->len,

								GFP_ATOMIC);

			} else {

				dmadir = DMA_TO_DEVICE;

				etd->bounce_buffer = kmemdup(etd->cpu_buffer,

								etd->len,

								GFP_ATOMIC);

			}

			if (!etd->bounce_buffer) {

				dev_err(imx21->dev, "failed bounce alloc\n");

				goto err_bounce_alloc;

			}



			etd->dma_handle =

				dma_map_single(imx21->dev,

						etd->bounce_buffer,

						etd->len,

						dmadir);

			if (dma_mapping_error(imx21->dev, etd->dma_handle)) {

				dev_err(imx21->dev, "failed bounce map\n");

				goto err_bounce_map;

			}

		}

	}



	clear_toggle_bit(imx21, USBH_ETDDONESTAT, etd_mask);

	set_register_bits(imx21, USBH_ETDDONEEN, etd_mask);

	clear_toggle_bit(imx21, USBH_XFILLSTAT, etd_mask);

	clear_toggle_bit(imx21, USBH_YFILLSTAT, etd_mask);



	if (dma) {

	if (etd->dma_handle) {

		set_register_bits(imx21, USB_ETDDMACHANLCLR, etd_mask);

		clear_toggle_bit(imx21, USBH_XBUFSTAT, etd_mask);

		clear_toggle_bit(imx21, USBH_YBUFSTAT, etd_mask);

		writel(dma, imx21->regs + USB_ETDSMSA(etd_num));

		writel(etd->dma_handle, imx21->regs + USB_ETDSMSA(etd_num));

		set_register_bits(imx21, USB_ETDDMAEN, etd_mask);

	} else {

		if (dir != TD_DIR_IN) {

			/* need to set for ZLP */

			/* need to set for ZLP and PIO */

			set_toggle_bit(imx21, USBH_XFILLSTAT, etd_mask);

			set_toggle_bit(imx21, USBH_YFILLSTAT, etd_mask);

		}
@@ -263,6 +342,14 @@ static void activate_etd(struct imx21 *imx21, 


	etd->active_count = 1;

	writel(etd_mask, imx21->regs + USBH_ETDENSET);

	return;



err_bounce_map:

	kfree(etd->bounce_buffer);



err_bounce_alloc:

	free_dmem(imx21, etd);

	nonisoc_urb_completed_for_etd(imx21, etd, -ENOMEM);

}



/* ===========================================	*/
@@ -325,7 +412,7 @@ static void activate_queued_etd(struct imx21 *imx21, 


	etd->dmem_offset = dmem_offset;

	urb_priv->active = 1;

	activate_etd(imx21, etd_num, etd->dma_handle, dir);

	activate_etd(imx21, etd_num, dir);

}



static void free_dmem(struct imx21 *imx21, struct etd_priv *etd)
@@ -385,7 +472,6 @@ static void free_epdmem(struct imx21 *imx21, struct usb_host_endpoint *ep) 
/* ===========================================	*/

/* End handling 				*/

/* ===========================================	*/

static void schedule_nonisoc_etd(struct imx21 *imx21, struct urb *urb);



/* Endpoint now idle - release it's ETD(s) or asssign to queued request */

static void ep_idle(struct imx21 *imx21, struct ep_priv *ep_priv)
@@ -448,6 +534,24 @@ __acquires(imx21->lock) 
		ep_idle(imx21, ep_priv);

}



static void nonisoc_urb_completed_for_etd(

	struct imx21 *imx21, struct etd_priv *etd, int status)

{

	struct usb_host_endpoint *ep = etd->ep;



	urb_done(imx21->hcd, etd->urb, status);

	etd->urb = NULL;



	if (!list_empty(&ep->urb_list)) {

		struct urb *urb = list_first_entry(

					&ep->urb_list, struct urb, urb_list);



		dev_vdbg(imx21->dev, "next URB %p\n", urb);

		schedule_nonisoc_etd(imx21, urb);

	}

}





/* ===========================================	*/

/* ISOC Handling ... 				*/

/* ===========================================	*/
@@ -500,6 +604,8 @@ too_late: 
		etd->ep = td->ep;

		etd->urb = td->urb;

		etd->len = td->len;

		etd->dma_handle = td->dma_handle;

		etd->cpu_buffer = td->cpu_buffer;



		debug_isoc_submitted(imx21, cur_frame, td);
@@ -513,16 +619,17 @@ too_late: 
			(TD_NOTACCESSED << DW3_COMPCODE0) |

			(td->len << DW3_PKTLEN0));



		activate_etd(imx21, etd_num, td->data, dir);

		activate_etd(imx21, etd_num, dir);

	}

}



static void isoc_etd_done(struct usb_hcd *hcd, struct urb *urb, int etd_num)

static void isoc_etd_done(struct usb_hcd *hcd, int etd_num)

{

	struct imx21 *imx21 = hcd_to_imx21(hcd);

	int etd_mask = 1 << etd_num;

	struct urb_priv *urb_priv = urb->hcpriv;

	struct etd_priv *etd = imx21->etd + etd_num;

	struct urb *urb = etd->urb;

	struct urb_priv *urb_priv = urb->hcpriv;

	struct td *td = etd->td;

	struct usb_host_endpoint *ep = etd->ep;

	int isoc_index = td->isoc_index;
@@ -556,8 +663,13 @@ static void isoc_etd_done(struct usb_hcd *hcd, struct urb *urb, int etd_num) 
			bytes_xfrd, td->len, urb, etd_num, isoc_index);

	}



	if (dir_in)

	if (dir_in) {

		clear_toggle_bit(imx21, USBH_XFILLSTAT, etd_mask);

		if (!etd->dma_handle)

			memcpy_fromio(etd->cpu_buffer,

				imx21->regs + USBOTG_DMEM + etd->dmem_offset,

				bytes_xfrd);

	}



	urb->actual_length += bytes_xfrd;

	urb->iso_frame_desc[isoc_index].actual_length = bytes_xfrd;
@@ -716,12 +828,14 @@ static int imx21_hc_urb_enqueue_isoc(struct usb_hcd *hcd, 
	/* set up transfers */

	td = urb_priv->isoc_td;

	for (i = 0; i < urb->number_of_packets; i++, td++) {

		unsigned int offset = urb->iso_frame_desc[i].offset;

		td->ep = ep;

		td->urb = urb;

		td->len = urb->iso_frame_desc[i].length;

		td->isoc_index = i;

		td->frame = wrap_frame(urb->start_frame + urb->interval * i);

		td->data = urb->transfer_dma + urb->iso_frame_desc[i].offset;

		td->dma_handle = urb->transfer_dma + offset;

		td->cpu_buffer = urb->transfer_buffer + offset;

		list_add_tail(&td->list, &ep_priv->td_list);

	}
@@ -812,13 +926,15 @@ static void schedule_nonisoc_etd(struct imx21 *imx21, struct urb *urb) 
	if (usb_pipecontrol(pipe) && (state != US_CTRL_DATA)) {

		if (state == US_CTRL_SETUP) {

			dir = TD_DIR_SETUP;

			if (unsuitable_for_dma(urb->setup_dma))

				unmap_urb_setup_for_dma(imx21->hcd, urb);

			etd->dma_handle = urb->setup_dma;

			etd->cpu_buffer = urb->setup_packet;

			bufround = 0;

			count = 8;

			datatoggle = TD_TOGGLE_DATA0;

		} else {	/* US_CTRL_ACK */

			dir = usb_pipeout(pipe) ? TD_DIR_IN : TD_DIR_OUT;

			etd->dma_handle = urb->transfer_dma;

			bufround = 0;

			count = 0;

			datatoggle = TD_TOGGLE_DATA1;
@@ -826,7 +942,11 @@ static void schedule_nonisoc_etd(struct imx21 *imx21, struct urb *urb) 
	} else {

		dir = usb_pipeout(pipe) ? TD_DIR_OUT : TD_DIR_IN;

		bufround = (dir == TD_DIR_IN) ? 1 : 0;

		if (unsuitable_for_dma(urb->transfer_dma))

			unmap_urb_for_dma(imx21->hcd, urb);



		etd->dma_handle = urb->transfer_dma;

		etd->cpu_buffer = urb->transfer_buffer;

		if (usb_pipebulk(pipe) && (state == US_BULK0))

			count = 0;

		else
@@ -901,14 +1021,15 @@ static void schedule_nonisoc_etd(struct imx21 *imx21, struct urb *urb) 
	/* enable the ETD to kick off transfer */

	dev_vdbg(imx21->dev, "Activating etd %d for %d bytes %s\n",

		etd_num, count, dir != TD_DIR_IN ? "out" : "in");

	activate_etd(imx21, etd_num, etd->dma_handle, dir);

	activate_etd(imx21, etd_num, dir);



}



static void nonisoc_etd_done(struct usb_hcd *hcd, struct urb *urb, int etd_num)

static void nonisoc_etd_done(struct usb_hcd *hcd, int etd_num)

{

	struct imx21 *imx21 = hcd_to_imx21(hcd);

	struct etd_priv *etd = &imx21->etd[etd_num];

	struct urb *urb = etd->urb;

	u32 etd_mask = 1 << etd_num;

	struct urb_priv *urb_priv = urb->hcpriv;

	int dir;
@@ -930,7 +1051,20 @@ static void nonisoc_etd_done(struct usb_hcd *hcd, struct urb *urb, int etd_num) 
	if (dir == TD_DIR_IN) {

		clear_toggle_bit(imx21, USBH_XFILLSTAT, etd_mask);

		clear_toggle_bit(imx21, USBH_YFILLSTAT, etd_mask);



		if (etd->bounce_buffer) {

			memcpy(etd->cpu_buffer, etd->bounce_buffer, bytes_xfrd);

			dma_unmap_single(imx21->dev,

				etd->dma_handle, etd->len, DMA_FROM_DEVICE);

		} else if (!etd->dma_handle && bytes_xfrd) {/* PIO */

			memcpy_fromio(etd->cpu_buffer,

				imx21->regs + USBOTG_DMEM + etd->dmem_offset,

				bytes_xfrd);

		}

	}



	kfree(etd->bounce_buffer);

	etd->bounce_buffer = NULL;

	free_dmem(imx21, etd);



	urb->error_count = 0;
@@ -988,24 +1122,15 @@ static void nonisoc_etd_done(struct usb_hcd *hcd, struct urb *urb, int etd_num) 
		break;

	}



	if (!etd_done) {

	if (etd_done)

		nonisoc_urb_completed_for_etd(imx21, etd, cc_to_error[cc]);

	else {

		dev_vdbg(imx21->dev, "next state=%d\n", urb_priv->state);

		schedule_nonisoc_etd(imx21, urb);

	} else {

		struct usb_host_endpoint *ep = urb->ep;



		urb_done(hcd, urb, cc_to_error[cc]);

		etd->urb = NULL;



		if (!list_empty(&ep->urb_list)) {

			urb = list_first_entry(&ep->urb_list,

				struct urb, urb_list);

			dev_vdbg(imx21->dev, "next URB %p\n", urb);

			schedule_nonisoc_etd(imx21, urb);

		}

	}

}





static struct ep_priv *alloc_ep(void)

{

	int i;
@@ -1146,9 +1271,13 @@ static int imx21_hc_urb_dequeue(struct usb_hcd *hcd, struct urb *urb, 
	} else if (urb_priv->active) {

		int etd_num = ep_priv->etd[0];

		if (etd_num != -1) {

			struct etd_priv *etd = &imx21->etd[etd_num];



			disactivate_etd(imx21, etd_num);

			free_dmem(imx21, &imx21->etd[etd_num]);

			imx21->etd[etd_num].urb = NULL;

			free_dmem(imx21, etd);

			etd->urb = NULL;

			kfree(etd->bounce_buffer);

			etd->bounce_buffer = NULL;

		}

	}
@@ -1248,9 +1377,9 @@ static void process_etds(struct usb_hcd *hcd, struct imx21 *imx21, int sof) 
		}



		if (usb_pipeisoc(etd->urb->pipe))

			isoc_etd_done(hcd, etd->urb, etd_num);

			isoc_etd_done(hcd, etd_num);

		else

			nonisoc_etd_done(hcd, etd->urb, etd_num);

			nonisoc_etd_done(hcd, etd_num);

	}



	/* only enable SOF interrupt if it may be needed for the kludge */
@@ -1718,6 +1847,7 @@ static int imx21_probe(struct platform_device *pdev) 
	}



	imx21 = hcd_to_imx21(hcd);

	imx21->hcd = hcd;

	imx21->dev = &pdev->dev;

	imx21->pdata = pdev->dev.platform_data;

	if (!imx21->pdata)

drivers/usb/host/imx21-hcd.h

+6 −2
Original line number Diff line number Diff line
@@ -250,6 +250,7 @@ 
#define USBCTRL_USB_BYP			(1 << 2)

#define USBCTRL_HOST1_TXEN_OE		(1 << 1)



#define USBOTG_DMEM		0x1000



/* Values in TD blocks */

#define TD_DIR_SETUP	    0
@@ -346,8 +347,8 @@ struct td { 
	struct list_head list;

	struct urb *urb;

	struct usb_host_endpoint *ep;

	dma_addr_t data;

	unsigned long buf_addr;

	dma_addr_t dma_handle;

	void *cpu_buffer;

	int len;

	int frame;

	int isoc_index;
@@ -360,6 +361,8 @@ struct etd_priv { 
	struct td *td;

	struct list_head queue;

	dma_addr_t dma_handle;

	void *cpu_buffer;

	void *bounce_buffer;

	int alloc;

	int len;

	int dmem_size;
@@ -412,6 +415,7 @@ struct debug_isoc_trace { 
struct imx21 {

	spinlock_t lock;

	struct device *dev;

	struct usb_hcd *hcd;

	struct mx21_usbh_platform_data *pdata;

	struct list_head dmem_list;

	struct list_head queue_for_etd; /* eps queued due to etd shortage */

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