linux/drivers/usb/musb/musbhsdma.c
Greg Kroah-Hartman 21b650c236 USB: musb: Remove redundant license text
Now that the SPDX tag is in all USB files, that identifies the license
in a specific and legally-defined manner.  So the extra GPL text wording
can be removed as it is no longer needed at all.

This is done on a quest to remove the 700+ different ways that files in
the kernel describe the GPL license text.  And there's unneeded stuff
like the address (sometimes incorrect) for the FSF which is never
needed.

No copyright headers or other non-license-description text was removed.

Cc: Maxime Ripard <maxime.ripard@free-electrons.com>
Cc: Chen-Yu Tsai <wens@csie.org>
Acked-by: Bin Liu <b-liu@ti.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-11-07 15:45:01 +01:00

388 lines
10 KiB
C

// SPDX-License-Identifier: GPL-2.0
/*
* MUSB OTG driver - support for Mentor's DMA controller
*
* Copyright 2005 Mentor Graphics Corporation
* Copyright (C) 2005-2007 by Texas Instruments
*/
#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;
}
}
}
}
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;
}
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;
}
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;
musb_dbg(musb, "%p, pkt_sz %d, addr %pad, len %d, mode %d",
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);
}
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;
musb_dbg(musb, "ep%d-%s pkt_sz %d, dma_addr %pad length %d, mode %d",
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;
}
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;
}
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) {
musb_dbg(musb, "spurious DMA irq");
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);
}
}
musb_dbg(musb, "int_hsdma = 0x%x", 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;
musb_dbg(musb, "ch %p, 0x%x -> 0x%x (%zu / %d) %s",
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;
}
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);
}
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;
}
EXPORT_SYMBOL_GPL(musbhs_dma_controller_create);