diff options
Diffstat (limited to 'drivers/dma/timb_dma.c')
| -rw-r--r-- | drivers/dma/timb_dma.c | 853 |
1 files changed, 853 insertions, 0 deletions
diff --git a/drivers/dma/timb_dma.c b/drivers/dma/timb_dma.c new file mode 100644 index 000000000000..4dd710246c79 --- /dev/null +++ b/drivers/dma/timb_dma.c @@ -0,0 +1,853 @@ +/* + * timb_dma.c timberdale FPGA DMA driver + * Copyright (c) 2010 Intel Corporation + * + * 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., 675 Mass Ave, Cambridge, MA 02139, USA. + */ + +/* Supports: + * Timberdale FPGA DMA engine + */ + +#include <linux/dmaengine.h> +#include <linux/dma-mapping.h> +#include <linux/init.h> +#include <linux/interrupt.h> +#include <linux/io.h> +#include <linux/module.h> +#include <linux/platform_device.h> + +#include <linux/timb_dma.h> + +#define DRIVER_NAME "timb-dma" + +/* Global DMA registers */ +#define TIMBDMA_ACR 0x34 +#define TIMBDMA_32BIT_ADDR 0x01 + +#define TIMBDMA_ISR 0x080000 +#define TIMBDMA_IPR 0x080004 +#define TIMBDMA_IER 0x080008 + +/* Channel specific registers */ +/* RX instances base addresses are 0x00, 0x40, 0x80 ... + * TX instances base addresses are 0x18, 0x58, 0x98 ... + */ +#define TIMBDMA_INSTANCE_OFFSET 0x40 +#define TIMBDMA_INSTANCE_TX_OFFSET 0x18 + +/* RX registers, relative the instance base */ +#define TIMBDMA_OFFS_RX_DHAR 0x00 +#define TIMBDMA_OFFS_RX_DLAR 0x04 +#define TIMBDMA_OFFS_RX_LR 0x0C +#define TIMBDMA_OFFS_RX_BLR 0x10 +#define TIMBDMA_OFFS_RX_ER 0x14 +#define TIMBDMA_RX_EN 0x01 +/* bytes per Row, video specific register + * which is placed after the TX registers... + */ +#define TIMBDMA_OFFS_RX_BPRR 0x30 + +/* TX registers, relative the instance base */ +#define TIMBDMA_OFFS_TX_DHAR 0x00 +#define TIMBDMA_OFFS_TX_DLAR 0x04 +#define TIMBDMA_OFFS_TX_BLR 0x0C +#define TIMBDMA_OFFS_TX_LR 0x14 + + +#define TIMB_DMA_DESC_SIZE 8 + +struct timb_dma_desc { + struct list_head desc_node; + struct dma_async_tx_descriptor txd; + u8 *desc_list; + unsigned int desc_list_len; + bool interrupt; +}; + +struct timb_dma_chan { + struct dma_chan chan; + void __iomem *membase; + spinlock_t lock; /* Used for mutual exclusion */ + dma_cookie_t last_completed_cookie; + bool ongoing; + struct list_head active_list; + struct list_head queue; + struct list_head free_list; + unsigned int bytes_per_line; + enum dma_data_direction direction; + unsigned int descs; /* Descriptors to allocate */ + unsigned int desc_elems; /* number of elems per descriptor */ +}; + +struct timb_dma { + struct dma_device dma; + void __iomem *membase; + struct tasklet_struct tasklet; + struct timb_dma_chan channels[0]; +}; + +static struct device *chan2dev(struct dma_chan *chan) +{ + return &chan->dev->device; +} +static struct device *chan2dmadev(struct dma_chan *chan) +{ + return chan2dev(chan)->parent->parent; +} + +static struct timb_dma *tdchantotd(struct timb_dma_chan *td_chan) +{ + int id = td_chan->chan.chan_id; + return (struct timb_dma *)((u8 *)td_chan - + id * sizeof(struct timb_dma_chan) - sizeof(struct timb_dma)); +} + +/* Must be called with the spinlock held */ +static void __td_enable_chan_irq(struct timb_dma_chan *td_chan) +{ + int id = td_chan->chan.chan_id; + struct timb_dma *td = tdchantotd(td_chan); + u32 ier; + + /* enable interrupt for this channel */ + ier = ioread32(td->membase + TIMBDMA_IER); + ier |= 1 << id; + dev_dbg(chan2dev(&td_chan->chan), "Enabling irq: %d, IER: 0x%x\n", id, + ier); + iowrite32(ier, td->membase + TIMBDMA_IER); +} + +/* Should be called with the spinlock held */ +static bool __td_dma_done_ack(struct timb_dma_chan *td_chan) +{ + int id = td_chan->chan.chan_id; + struct timb_dma *td = (struct timb_dma *)((u8 *)td_chan - + id * sizeof(struct timb_dma_chan) - sizeof(struct timb_dma)); + u32 isr; + bool done = false; + + dev_dbg(chan2dev(&td_chan->chan), "Checking irq: %d, td: %p\n", id, td); + + isr = ioread32(td->membase + TIMBDMA_ISR) & (1 << id); + if (isr) { + iowrite32(isr, td->membase + TIMBDMA_ISR); + done = true; + } + + return done; +} + +static void __td_unmap_desc(struct timb_dma_chan *td_chan, const u8 *dma_desc, + bool single) +{ + dma_addr_t addr; + int len; + + addr = (dma_desc[7] << 24) | (dma_desc[6] << 16) | (dma_desc[5] << 8) | + dma_desc[4]; + + len = (dma_desc[3] << 8) | dma_desc[2]; + + if (single) + dma_unmap_single(chan2dev(&td_chan->chan), addr, len, + td_chan->direction); + else + dma_unmap_page(chan2dev(&td_chan->chan), addr, len, + td_chan->direction); +} + +static void __td_unmap_descs(struct timb_dma_desc *td_desc, bool single) +{ + struct timb_dma_chan *td_chan = container_of(td_desc->txd.chan, + struct timb_dma_chan, chan); + u8 *descs; + + for (descs = td_desc->desc_list; ; descs += TIMB_DMA_DESC_SIZE) { + __td_unmap_desc(td_chan, descs, single); + if (descs[0] & 0x02) + break; + } +} + +static int td_fill_desc(struct timb_dma_chan *td_chan, u8 *dma_desc, + struct scatterlist *sg, bool last) +{ + if (sg_dma_len(sg) > USHORT_MAX) { + dev_err(chan2dev(&td_chan->chan), "Too big sg element\n"); + return -EINVAL; + } + + /* length must be word aligned */ + if (sg_dma_len(sg) % sizeof(u32)) { + dev_err(chan2dev(&td_chan->chan), "Incorrect length: %d\n", + sg_dma_len(sg)); + return -EINVAL; + } + + dev_dbg(chan2dev(&td_chan->chan), "desc: %p, addr: %p\n", + dma_desc, (void *)(int)sg_dma_address(sg)); + + dma_desc[7] = (sg_dma_address(sg) >> 24) & 0xff; + dma_desc[6] = (sg_dma_address(sg) >> 16) & 0xff; + dma_desc[5] = (sg_dma_address(sg) >> 8) & 0xff; + dma_desc[4] = (sg_dma_address(sg) >> 0) & 0xff; + + dma_desc[3] = (sg_dma_len(sg) >> 8) & 0xff; + dma_desc[2] = (sg_dma_len(sg) >> 0) & 0xff; + + dma_desc[1] = 0x00; + dma_desc[0] = 0x21 | (last ? 0x02 : 0); /* tran, valid */ + + return 0; +} + +/* Must be called with the spinlock held */ +static void __td_start_dma(struct timb_dma_chan *td_chan) +{ + struct timb_dma_desc *td_desc; + + if (td_chan->ongoing) { + dev_err(chan2dev(&td_chan->chan), + "Transfer already ongoing\n"); + return; + } + + td_desc = list_entry(td_chan->active_list.next, struct timb_dma_desc, + desc_node); + + dev_dbg(chan2dev(&td_chan->chan), + "td_chan: %p, chan: %d, membase: %p\n", + td_chan, td_chan->chan.chan_id, td_chan->membase); + + if (td_chan->direction == DMA_FROM_DEVICE) { + + /* descriptor address */ + iowrite32(0, td_chan->membase + TIMBDMA_OFFS_RX_DHAR); + iowrite32(td_desc->txd.phys, td_chan->membase + + TIMBDMA_OFFS_RX_DLAR); + /* Bytes per line */ + iowrite32(td_chan->bytes_per_line, td_chan->membase + + TIMBDMA_OFFS_RX_BPRR); + /* enable RX */ + iowrite32(TIMBDMA_RX_EN, td_chan->membase + TIMBDMA_OFFS_RX_ER); + } else { + /* address high */ + iowrite32(0, td_chan->membase + TIMBDMA_OFFS_TX_DHAR); + iowrite32(td_desc->txd.phys, td_chan->membase + + TIMBDMA_OFFS_TX_DLAR); + } + + td_chan->ongoing = true; + + if (td_desc->interrupt) + __td_enable_chan_irq(td_chan); +} + +static void __td_finish(struct timb_dma_chan *td_chan) +{ + dma_async_tx_callback callback; + void *param; + struct dma_async_tx_descriptor *txd; + struct timb_dma_desc *td_desc; + + /* can happen if the descriptor is canceled */ + if (list_empty(&td_chan->active_list)) + return; + + td_desc = list_entry(td_chan->active_list.next, struct timb_dma_desc, + desc_node); + txd = &td_desc->txd; + + dev_dbg(chan2dev(&td_chan->chan), "descriptor %u complete\n", + txd->cookie); + + /* make sure to stop the transfer */ + if (td_chan->direction == DMA_FROM_DEVICE) + iowrite32(0, td_chan->membase + TIMBDMA_OFFS_RX_ER); +/* Currently no support for stopping DMA transfers + else + iowrite32(0, td_chan->membase + TIMBDMA_OFFS_TX_DLAR); +*/ + td_chan->last_completed_cookie = txd->cookie; + td_chan->ongoing = false; + + callback = txd->callback; + param = txd->callback_param; + + list_move(&td_desc->desc_node, &td_chan->free_list); + + if (!(txd->flags & DMA_COMPL_SKIP_SRC_UNMAP)) + __td_unmap_descs(td_desc, + txd->flags & DMA_COMPL_SRC_UNMAP_SINGLE); + + /* + * The API requires that no submissions are done from a + * callback, so we don't need to drop the lock here + */ + if (callback) + callback(param); +} + +static u32 __td_ier_mask(struct timb_dma *td) +{ + int i; + u32 ret = 0; + + for (i = 0; i < td->dma.chancnt; i++) { + struct timb_dma_chan *td_chan = td->channels + i; + if (td_chan->ongoing) { + struct timb_dma_desc *td_desc = + list_entry(td_chan->active_list.next, + struct timb_dma_desc, desc_node); + if (td_desc->interrupt) + ret |= 1 << i; + } + } + + return ret; +} + +static void __td_start_next(struct timb_dma_chan *td_chan) +{ + struct timb_dma_desc *td_desc; + + BUG_ON(list_empty(&td_chan->queue)); + BUG_ON(td_chan->ongoing); + + td_desc = list_entry(td_chan->queue.next, struct timb_dma_desc, + desc_node); + + dev_dbg(chan2dev(&td_chan->chan), "%s: started %u\n", + __func__, td_desc->txd.cookie); + + list_move(&td_desc->desc_node, &td_chan->active_list); + __td_start_dma(td_chan); +} + +static dma_cookie_t td_tx_submit(struct dma_async_tx_descriptor *txd) +{ + struct timb_dma_desc *td_desc = container_of(txd, struct timb_dma_desc, + txd); + struct timb_dma_chan *td_chan = container_of(txd->chan, + struct timb_dma_chan, chan); + dma_cookie_t cookie; + + spin_lock_bh(&td_chan->lock); + + cookie = txd->chan->cookie; + if (++cookie < 0) + cookie = 1; + txd->chan->cookie = cookie; + txd->cookie = cookie; + + if (list_empty(&td_chan->active_list)) { + dev_dbg(chan2dev(txd->chan), "%s: started %u\n", __func__, + txd->cookie); + list_add_tail(&td_desc->desc_node, &td_chan->active_list); + __td_start_dma(td_chan); + } else { + dev_dbg(chan2dev(txd->chan), "tx_submit: queued %u\n", + txd->cookie); + + list_add_tail(&td_desc->desc_node, &td_chan->queue); + } + + spin_unlock_bh(&td_chan->lock); + + return cookie; +} + +static struct timb_dma_desc *td_alloc_init_desc(struct timb_dma_chan *td_chan) +{ + struct dma_chan *chan = &td_chan->chan; + struct timb_dma_desc *td_desc; + int err; + + td_desc = kzalloc(sizeof(struct timb_dma_desc), GFP_KERNEL); + if (!td_desc) { + dev_err(chan2dev(chan), "Failed to alloc descriptor\n"); + goto err; + } + + td_desc->desc_list_len = td_chan->desc_elems * TIMB_DMA_DESC_SIZE; + + td_desc->desc_list = kzalloc(td_desc->desc_list_len, GFP_KERNEL); + if (!td_desc->desc_list) { + dev_err(chan2dev(chan), "Failed to alloc descriptor\n"); + goto err; + } + + dma_async_tx_descriptor_init(&td_desc->txd, chan); + td_desc->txd.tx_submit = td_tx_submit; + td_desc->txd.flags = DMA_CTRL_ACK; + + td_desc->txd.phys = dma_map_single(chan2dmadev(chan), + td_desc->desc_list, td_desc->desc_list_len, DMA_TO_DEVICE); + + err = dma_mapping_error(chan2dmadev(chan), td_desc->txd.phys); + if (err) { + dev_err(chan2dev(chan), "DMA mapping error: %d\n", err); + goto err; + } + + return td_desc; +err: + kfree(td_desc->desc_list); + kfree(td_desc); + + return NULL; + +} + +static void td_free_desc(struct timb_dma_desc *td_desc) +{ + dev_dbg(chan2dev(td_desc->txd.chan), "Freeing desc: %p\n", td_desc); + dma_unmap_single(chan2dmadev(td_desc->txd.chan), td_desc->txd.phys, + td_desc->desc_list_len, DMA_TO_DEVICE); + + kfree(td_desc->desc_list); + kfree(td_desc); +} + +static void td_desc_put(struct timb_dma_chan *td_chan, + struct timb_dma_desc *td_desc) +{ + dev_dbg(chan2dev(&td_chan->chan), "Putting desc: %p\n", td_desc); + + spin_lock_bh(&td_chan->lock); + list_add(&td_desc->desc_node, &td_chan->free_list); + spin_unlock_bh(&td_chan->lock); +} + +static struct timb_dma_desc *td_desc_get(struct timb_dma_chan *td_chan) +{ + struct timb_dma_desc *td_desc, *_td_desc; + struct timb_dma_desc *ret = NULL; + + spin_lock_bh(&td_chan->lock); + list_for_each_entry_safe(td_desc, _td_desc, &td_chan->free_list, + desc_node) { + if (async_tx_test_ack(&td_desc->txd)) { + list_del(&td_desc->desc_node); + ret = td_desc; + break; + } + dev_dbg(chan2dev(&td_chan->chan), "desc %p not ACKed\n", + td_desc); + } + spin_unlock_bh(&td_chan->lock); + + return ret; +} + +static int td_alloc_chan_resources(struct dma_chan *chan) +{ + struct timb_dma_chan *td_chan = + container_of(chan, struct timb_dma_chan, chan); + int i; + + dev_dbg(chan2dev(chan), "%s: entry\n", __func__); + + BUG_ON(!list_empty(&td_chan->free_list)); + for (i = 0; i < td_chan->descs; i++) { + struct timb_dma_desc *td_desc = td_alloc_init_desc(td_chan); + if (!td_desc) { + if (i) + break; + else { + dev_err(chan2dev(chan), + "Couldnt allocate any descriptors\n"); + return -ENOMEM; + } + } + + td_desc_put(td_chan, td_desc); + } + + spin_lock_bh(&td_chan->lock); + td_chan->last_completed_cookie = 1; + chan->cookie = 1; + spin_unlock_bh(&td_chan->lock); + + return 0; +} + +static void td_free_chan_resources(struct dma_chan *chan) +{ + struct timb_dma_chan *td_chan = + container_of(chan, struct timb_dma_chan, chan); + struct timb_dma_desc *td_desc, *_td_desc; + LIST_HEAD(list); + + dev_dbg(chan2dev(chan), "%s: Entry\n", __func__); + + /* check that all descriptors are free */ + BUG_ON(!list_empty(&td_chan->active_list)); + BUG_ON(!list_empty(&td_chan->queue)); + + spin_lock_bh(&td_chan->lock); + list_splice_init(&td_chan->free_list, &list); + spin_unlock_bh(&td_chan->lock); + + list_for_each_entry_safe(td_desc, _td_desc, &list, desc_node) { + dev_dbg(chan2dev(chan), "%s: Freeing desc: %p\n", __func__, + td_desc); + td_free_desc(td_desc); + } +} + +static enum dma_status td_is_tx_complete(struct dma_chan *chan, + dma_cookie_t cookie, dma_cookie_t *done, dma_cookie_t *used) +{ + struct timb_dma_chan *td_chan = + container_of(chan, struct timb_dma_chan, chan); + dma_cookie_t last_used; + dma_cookie_t last_complete; + int ret; + + dev_dbg(chan2dev(chan), "%s: Entry\n", __func__); + + last_complete = td_chan->last_completed_cookie; + last_used = chan->cookie; + + ret = dma_async_is_complete(cookie, last_complete, last_used); + + if (done) + *done = last_complete; + if (used) + *used = last_used; + + dev_dbg(chan2dev(chan), + "%s: exit, ret: %d, last_complete: %d, last_used: %d\n", + __func__, ret, last_complete, last_used); + + return ret; +} + +static void td_issue_pending(struct dma_chan *chan) +{ + struct timb_dma_chan *td_chan = + container_of(chan, struct timb_dma_chan, chan); + + dev_dbg(chan2dev(chan), "%s: Entry\n", __func__); + spin_lock_bh(&td_chan->lock); + + if (!list_empty(&td_chan->active_list)) + /* transfer ongoing */ + if (__td_dma_done_ack(td_chan)) + __td_finish(td_chan); + + if (list_empty(&td_chan->active_list) && !list_empty(&td_chan->queue)) + __td_start_next(td_chan); + + spin_unlock_bh(&td_chan->lock); +} + +static struct dma_async_tx_descriptor *td_prep_slave_sg(struct dma_chan *chan, + struct scatterlist *sgl, unsigned int sg_len, + enum dma_data_direction direction, unsigned long flags) +{ + struct timb_dma_chan *td_chan = + container_of(chan, struct timb_dma_chan, chan); + struct timb_dma_desc *td_desc; + struct scatterlist *sg; + unsigned int i; + unsigned int desc_usage = 0; + + if (!sgl || !sg_len) { + dev_err(chan2dev(chan), "%s: No SG list\n", __func__); + return NULL; + } + + /* even channels are for RX, odd for TX */ + if (td_chan->direction != direction) { + dev_err(chan2dev(chan), + "Requesting channel in wrong direction\n"); + return NULL; + } + + td_desc = td_desc_get(td_chan); + if (!td_desc) { + dev_err(chan2dev(chan), "Not enough descriptors available\n"); + return NULL; + } + + td_desc->interrupt = (flags & DMA_PREP_INTERRUPT) != 0; + + for_each_sg(sgl, sg, sg_len, i) { + int err; + if (desc_usage > td_desc->desc_list_len) { + dev_err(chan2dev(chan), "No descriptor space\n"); + return NULL; + } + + err = td_fill_desc(td_chan, td_desc->desc_list + desc_usage, sg, + i == (sg_len - 1)); + if (err) { + dev_err(chan2dev(chan), "Failed to update desc: %d\n", + err); + td_desc_put(td_chan, td_desc); + return NULL; + } + desc_usage += TIMB_DMA_DESC_SIZE; + } + + dma_sync_single_for_device(chan2dmadev(chan), td_desc->txd.phys, + td_desc->desc_list_len, DMA_TO_DEVICE); + + return &td_desc->txd; +} + +static void td_terminate_all(struct dma_chan *chan) +{ + struct timb_dma_chan *td_chan = + container_of(chan, struct timb_dma_chan, chan); + struct timb_dma_desc *td_desc, *_td_desc; + + dev_dbg(chan2dev(chan), "%s: Entry\n", __func__); + + /* first the easy part, put the queue into the free list */ + spin_lock_bh(&td_chan->lock); + list_for_each_entry_safe(td_desc, _td_desc, &td_chan->queue, + desc_node) + list_move(&td_desc->desc_node, &td_chan->free_list); + + /* now tear down the runnning */ + __td_finish(td_chan); + spin_unlock_bh(&td_chan->lock); +} + +static void td_tasklet(unsigned long data) +{ + struct timb_dma *td = (struct timb_dma *)data; + u32 isr; + u32 ipr; + u32 ier; + int i; + + isr = ioread32(td->membase + TIMBDMA_ISR); + ipr = isr & __td_ier_mask(td); + + /* ack the interrupts */ + iowrite32(ipr, td->membase + TIMBDMA_ISR); + + for (i = 0; i < td->dma.chancnt; i++) + if (ipr & (1 << i)) { + struct timb_dma_chan *td_chan = td->channels + i; + spin_lock(&td_chan->lock); + __td_finish(td_chan); + if (!list_empty(&td_chan->queue)) + __td_start_next(td_chan); + spin_unlock(&td_chan->lock); + } + + ier = __td_ier_mask(td); + iowrite32(ier, td->membase + TIMBDMA_IER); +} + + +static irqreturn_t td_irq(int irq, void *devid) +{ + struct timb_dma *td = devid; + u32 ipr = ioread32(td->membase + TIMBDMA_IPR); + + if (ipr) { + /* disable interrupts, will be re-enabled in tasklet */ + iowrite32(0, td->membase + TIMBDMA_IER); + + tasklet_schedule(&td->tasklet); + + return IRQ_HANDLED; + } else + return IRQ_NONE; +} + + +static int __devinit td_probe(struct platform_device *pdev) +{ + struct timb_dma_platform_data *pdata = pdev->dev.platform_data; + struct timb_dma *td; + struct resource *iomem; + int irq; + int err; + int i; + + if (!pdata) { + dev_err(&pdev->dev, "No platform data\n"); + return -EINVAL; + } + + iomem = platform_get_resource(pdev, IORESOURCE_MEM, 0); + if (!iomem) + return -EINVAL; + + irq = platform_get_irq(pdev, 0); + if (irq < 0) + return irq; + + if (!request_mem_region(iomem->start, resource_size(iomem), + DRIVER_NAME)) + return -EBUSY; + + td = kzalloc(sizeof(struct timb_dma) + + sizeof(struct timb_dma_chan) * pdata->nr_channels, GFP_KERNEL); + if (!td) { + err = -ENOMEM; + goto err_release_region; + } + + dev_dbg(&pdev->dev, "Allocated TD: %p\n", td); + + td->membase = ioremap(iomem->start, resource_size(iomem)); + if (!td->membase) { + dev_err(&pdev->dev, "Failed to remap I/O memory\n"); + err = -ENOMEM; + goto err_free_mem; + } + + /* 32bit addressing */ + iowrite32(TIMBDMA_32BIT_ADDR, td->membase + TIMBDMA_ACR); + + /* disable and clear any interrupts */ + iowrite32(0x0, td->membase + TIMBDMA_IER); + iowrite32(0xFFFFFFFF, td->membase + TIMBDMA_ISR); + + tasklet_init(&td->tasklet, td_tasklet, (unsigned long)td); + + err = request_irq(irq, td_irq, IRQF_SHARED, DRIVER_NAME, td); + if (err) { + dev_err(&pdev->dev, "Failed to request IRQ\n"); + goto err_tasklet_kill; + } + + td->dma.device_alloc_chan_resources = td_alloc_chan_resources; + td->dma.device_free_chan_resources = td_free_chan_resources; + td->dma.device_is_tx_complete = td_is_tx_complete; + td->dma.device_issue_pending = td_issue_pending; + + dma_cap_set(DMA_SLAVE, td->dma.cap_mask); + dma_cap_set(DMA_PRIVATE, td->dma.cap_mask); + td->dma.device_prep_slave_sg = td_prep_slave_sg; + td->dma.device_terminate_all = td_terminate_all; + + td->dma.dev = &pdev->dev; + + INIT_LIST_HEAD(&td->dma.channels); + + for (i = 0; i < pdata->nr_channels; i++, td->dma.chancnt++) { + struct timb_dma_chan *td_chan = &td->channels[i]; + struct timb_dma_platform_data_channel *pchan = + pdata->channels + i; + + /* even channels are RX, odd are TX */ + if (((i % 2) && pchan->rx) || (!(i % 2) && !pchan->rx)) { + dev_err(&pdev->dev, "Wrong channel configuration\n"); + err = -EINVAL; + goto err_tasklet_kill; + } + + td_chan->chan.device = &td->dma; + td_chan->chan.cookie = 1; + td_chan->chan.chan_id = i; + spin_lock_init(&td_chan->lock); + INIT_LIST_HEAD(&td_chan->active_list); + INIT_LIST_HEAD(&td_chan->queue); + INIT_LIST_HEAD(&td_chan->free_list); + + td_chan->descs = pchan->descriptors; + td_chan->desc_elems = pchan->descriptor_elements; + td_chan->bytes_per_line = pchan->bytes_per_line; + td_chan->direction = pchan->rx ? DMA_FROM_DEVICE : + DMA_TO_DEVICE; + + td_chan->membase = td->membase + + (i / 2) * TIMBDMA_INSTANCE_OFFSET + + (pchan->rx ? 0 : TIMBDMA_INSTANCE_TX_OFFSET); + + dev_dbg(&pdev->dev, "Chan: %d, membase: %p\n", + i, td_chan->membase); + + list_add_tail(&td_chan->chan.device_node, &td->dma.channels); + } + + err = dma_async_device_register(&td->dma); + if (err) { + dev_err(&pdev->dev, "Failed to register async device\n"); + goto err_free_irq; + } + + platform_set_drvdata(pdev, td); + + dev_dbg(&pdev->dev, "Probe result: %d\n", err); + return err; + +err_free_irq: + free_irq(irq, td); +err_tasklet_kill: + tasklet_kill(&td->tasklet); + iounmap(td->membase); +err_free_mem: + kfree(td); +err_release_region: + release_mem_region(iomem->start, resource_size(iomem)); + + return err; + +} + +static int __devexit td_remove(struct platform_device *pdev) +{ + struct timb_dma *td = platform_get_drvdata(pdev); + struct resource *iomem = platform_get_resource(pdev, IORESOURCE_MEM, 0); + int irq = platform_get_irq(pdev, 0); + + dma_async_device_unregister(&td->dma); + free_irq(irq, td); + tasklet_kill(&td->tasklet); + iounmap(td->membase); + kfree(td); + release_mem_region(iomem->start, resource_size(iomem)); + + platform_set_drvdata(pdev, NULL); + + dev_dbg(&pdev->dev, "Removed...\n"); + return 0; +} + +static struct platform_driver td_driver = { + .driver = { + .name = DRIVER_NAME, + .owner = THIS_MODULE, + }, + .probe = td_probe, + .remove = __exit_p(td_remove), +}; + +static int __init td_init(void) +{ + return platform_driver_register(&td_driver); +} +module_init(td_init); + +static void __exit td_exit(void) +{ + platform_driver_unregister(&td_driver); +} +module_exit(td_exit); + +MODULE_LICENSE("GPL v2"); +MODULE_DESCRIPTION("Timberdale DMA controller driver"); +MODULE_AUTHOR("Pelagicore AB <info@pelagicore.com>"); +MODULE_ALIAS("platform:"DRIVER_NAME); |