From 9a7b8e002e331d0599127f16613c32f425a14f2c Mon Sep 17 00:00:00 2001 From: Guennadi Liakhovetski Date: Wed, 9 May 2012 17:09:13 +0200 Subject: dmaengine: add an shdma-base library This patch extracts code from shdma.c, that does not directly deal with hardware implementation details and can be re-used with diverse DMA controller variants, found on SH-based SoCs. Signed-off-by: Guennadi Liakhovetski Cc: Sascha Hauer Signed-off-by: Vinod Koul --- drivers/dma/sh/shdma-base.c | 868 ++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 868 insertions(+) create mode 100644 drivers/dma/sh/shdma-base.c (limited to 'drivers/dma/sh/shdma-base.c') diff --git a/drivers/dma/sh/shdma-base.c b/drivers/dma/sh/shdma-base.c new file mode 100644 index 000000000000..ff060d0da908 --- /dev/null +++ b/drivers/dma/sh/shdma-base.c @@ -0,0 +1,868 @@ +/* + * Dmaengine driver base library for DMA controllers, found on SH-based SoCs + * + * extracted from shdma.c + * + * Copyright (C) 2011-2012 Guennadi Liakhovetski + * Copyright (C) 2009 Nobuhiro Iwamatsu + * Copyright (C) 2009 Renesas Solutions, Inc. All rights reserved. + * Copyright (C) 2007 Freescale Semiconductor, Inc. All rights reserved. + * + * This is free software; you can redistribute it and/or modify + * it under the terms of version 2 of the GNU General Public License as + * published by the Free Software Foundation. + */ + +#include +#include +#include +#include +#include +#include +#include +#include +#include + +#include "../dmaengine.h" + +/* DMA descriptor control */ +enum shdma_desc_status { + DESC_IDLE, + DESC_PREPARED, + DESC_SUBMITTED, + DESC_COMPLETED, /* completed, have to call callback */ + DESC_WAITING, /* callback called, waiting for ack / re-submit */ +}; + +#define NR_DESCS_PER_CHANNEL 32 + +#define to_shdma_chan(c) container_of(c, struct shdma_chan, dma_chan) +#define to_shdma_dev(d) container_of(d, struct shdma_dev, dma_dev) + +/* + * For slave DMA we assume, that there is a finite number of DMA slaves in the + * system, and that each such slave can only use a finite number of channels. + * We use slave channel IDs to make sure, that no such slave channel ID is + * allocated more than once. + */ +static unsigned int slave_num = 256; +module_param(slave_num, uint, 0444); + +/* A bitmask with slave_num bits */ +static unsigned long *shdma_slave_used; + +/* Called under spin_lock_irq(&schan->chan_lock") */ +static void shdma_chan_xfer_ld_queue(struct shdma_chan *schan) +{ + struct shdma_dev *sdev = to_shdma_dev(schan->dma_chan.device); + const struct shdma_ops *ops = sdev->ops; + struct shdma_desc *sdesc; + + /* DMA work check */ + if (ops->channel_busy(schan)) + return; + + /* Find the first not transferred descriptor */ + list_for_each_entry(sdesc, &schan->ld_queue, node) + if (sdesc->mark == DESC_SUBMITTED) { + ops->start_xfer(schan, sdesc); + break; + } +} + +static dma_cookie_t shdma_tx_submit(struct dma_async_tx_descriptor *tx) +{ + struct shdma_desc *chunk, *c, *desc = + container_of(tx, struct shdma_desc, async_tx), + *last = desc; + struct shdma_chan *schan = to_shdma_chan(tx->chan); + struct shdma_slave *slave = tx->chan->private; + dma_async_tx_callback callback = tx->callback; + dma_cookie_t cookie; + bool power_up; + + spin_lock_irq(&schan->chan_lock); + + power_up = list_empty(&schan->ld_queue); + + cookie = dma_cookie_assign(tx); + + /* Mark all chunks of this descriptor as submitted, move to the queue */ + list_for_each_entry_safe(chunk, c, desc->node.prev, node) { + /* + * All chunks are on the global ld_free, so, we have to find + * the end of the chain ourselves + */ + if (chunk != desc && (chunk->mark == DESC_IDLE || + chunk->async_tx.cookie > 0 || + chunk->async_tx.cookie == -EBUSY || + &chunk->node == &schan->ld_free)) + break; + chunk->mark = DESC_SUBMITTED; + /* Callback goes to the last chunk */ + chunk->async_tx.callback = NULL; + chunk->cookie = cookie; + list_move_tail(&chunk->node, &schan->ld_queue); + last = chunk; + + dev_dbg(schan->dev, "submit #%d@%p on %d\n", + tx->cookie, &last->async_tx, schan->id); + } + + last->async_tx.callback = callback; + last->async_tx.callback_param = tx->callback_param; + + if (power_up) { + int ret; + schan->pm_state = SHDMA_PM_BUSY; + + ret = pm_runtime_get(schan->dev); + + spin_unlock_irq(&schan->chan_lock); + if (ret < 0) + dev_err(schan->dev, "%s(): GET = %d\n", __func__, ret); + + pm_runtime_barrier(schan->dev); + + spin_lock_irq(&schan->chan_lock); + + /* Have we been reset, while waiting? */ + if (schan->pm_state != SHDMA_PM_ESTABLISHED) { + struct shdma_dev *sdev = + to_shdma_dev(schan->dma_chan.device); + const struct shdma_ops *ops = sdev->ops; + dev_dbg(schan->dev, "Bring up channel %d\n", + schan->id); + /* + * TODO: .xfer_setup() might fail on some platforms. + * Make it int then, on error remove chunks from the + * queue again + */ + ops->setup_xfer(schan, slave); + + if (schan->pm_state == SHDMA_PM_PENDING) + shdma_chan_xfer_ld_queue(schan); + schan->pm_state = SHDMA_PM_ESTABLISHED; + } + } else { + /* + * Tell .device_issue_pending() not to run the queue, interrupts + * will do it anyway + */ + schan->pm_state = SHDMA_PM_PENDING; + } + + spin_unlock_irq(&schan->chan_lock); + + return cookie; +} + +/* Called with desc_lock held */ +static struct shdma_desc *shdma_get_desc(struct shdma_chan *schan) +{ + struct shdma_desc *sdesc; + + list_for_each_entry(sdesc, &schan->ld_free, node) + if (sdesc->mark != DESC_PREPARED) { + BUG_ON(sdesc->mark != DESC_IDLE); + list_del(&sdesc->node); + return sdesc; + } + + return NULL; +} + +static int shdma_alloc_chan_resources(struct dma_chan *chan) +{ + struct shdma_chan *schan = to_shdma_chan(chan); + struct shdma_dev *sdev = to_shdma_dev(schan->dma_chan.device); + const struct shdma_ops *ops = sdev->ops; + struct shdma_desc *desc; + struct shdma_slave *slave = chan->private; + int ret, i; + + /* + * This relies on the guarantee from dmaengine that alloc_chan_resources + * never runs concurrently with itself or free_chan_resources. + */ + if (slave) { + if (slave->slave_id >= slave_num) { + ret = -EINVAL; + goto evalid; + } + + if (test_and_set_bit(slave->slave_id, shdma_slave_used)) { + ret = -EBUSY; + goto etestused; + } + + ret = ops->set_slave(schan, slave); + if (ret < 0) + goto esetslave; + } + + schan->desc = kcalloc(NR_DESCS_PER_CHANNEL, + sdev->desc_size, GFP_KERNEL); + if (!schan->desc) { + ret = -ENOMEM; + goto edescalloc; + } + schan->desc_num = NR_DESCS_PER_CHANNEL; + + for (i = 0; i < NR_DESCS_PER_CHANNEL; i++) { + desc = ops->embedded_desc(schan->desc, i); + dma_async_tx_descriptor_init(&desc->async_tx, + &schan->dma_chan); + desc->async_tx.tx_submit = shdma_tx_submit; + desc->mark = DESC_IDLE; + + list_add(&desc->node, &schan->ld_free); + } + + return NR_DESCS_PER_CHANNEL; + +edescalloc: + if (slave) +esetslave: + clear_bit(slave->slave_id, shdma_slave_used); +etestused: +evalid: + chan->private = NULL; + return ret; +} + +static dma_async_tx_callback __ld_cleanup(struct shdma_chan *schan, bool all) +{ + struct shdma_desc *desc, *_desc; + /* Is the "exposed" head of a chain acked? */ + bool head_acked = false; + dma_cookie_t cookie = 0; + dma_async_tx_callback callback = NULL; + void *param = NULL; + unsigned long flags; + + spin_lock_irqsave(&schan->chan_lock, flags); + list_for_each_entry_safe(desc, _desc, &schan->ld_queue, node) { + struct dma_async_tx_descriptor *tx = &desc->async_tx; + + BUG_ON(tx->cookie > 0 && tx->cookie != desc->cookie); + BUG_ON(desc->mark != DESC_SUBMITTED && + desc->mark != DESC_COMPLETED && + desc->mark != DESC_WAITING); + + /* + * queue is ordered, and we use this loop to (1) clean up all + * completed descriptors, and to (2) update descriptor flags of + * any chunks in a (partially) completed chain + */ + if (!all && desc->mark == DESC_SUBMITTED && + desc->cookie != cookie) + break; + + if (tx->cookie > 0) + cookie = tx->cookie; + + if (desc->mark == DESC_COMPLETED && desc->chunks == 1) { + if (schan->dma_chan.completed_cookie != desc->cookie - 1) + dev_dbg(schan->dev, + "Completing cookie %d, expected %d\n", + desc->cookie, + schan->dma_chan.completed_cookie + 1); + schan->dma_chan.completed_cookie = desc->cookie; + } + + /* Call callback on the last chunk */ + if (desc->mark == DESC_COMPLETED && tx->callback) { + desc->mark = DESC_WAITING; + callback = tx->callback; + param = tx->callback_param; + dev_dbg(schan->dev, "descriptor #%d@%p on %d callback\n", + tx->cookie, tx, schan->id); + BUG_ON(desc->chunks != 1); + break; + } + + if (tx->cookie > 0 || tx->cookie == -EBUSY) { + if (desc->mark == DESC_COMPLETED) { + BUG_ON(tx->cookie < 0); + desc->mark = DESC_WAITING; + } + head_acked = async_tx_test_ack(tx); + } else { + switch (desc->mark) { + case DESC_COMPLETED: + desc->mark = DESC_WAITING; + /* Fall through */ + case DESC_WAITING: + if (head_acked) + async_tx_ack(&desc->async_tx); + } + } + + dev_dbg(schan->dev, "descriptor %p #%d completed.\n", + tx, tx->cookie); + + if (((desc->mark == DESC_COMPLETED || + desc->mark == DESC_WAITING) && + async_tx_test_ack(&desc->async_tx)) || all) { + /* Remove from ld_queue list */ + desc->mark = DESC_IDLE; + + list_move(&desc->node, &schan->ld_free); + + if (list_empty(&schan->ld_queue)) { + dev_dbg(schan->dev, "Bring down channel %d\n", schan->id); + pm_runtime_put(schan->dev); + schan->pm_state = SHDMA_PM_ESTABLISHED; + } + } + } + + if (all && !callback) + /* + * Terminating and the loop completed normally: forgive + * uncompleted cookies + */ + schan->dma_chan.completed_cookie = schan->dma_chan.cookie; + + spin_unlock_irqrestore(&schan->chan_lock, flags); + + if (callback) + callback(param); + + return callback; +} + +/* + * shdma_chan_ld_cleanup - Clean up link descriptors + * + * Clean up the ld_queue of DMA channel. + */ +static void shdma_chan_ld_cleanup(struct shdma_chan *schan, bool all) +{ + while (__ld_cleanup(schan, all)) + ; +} + +/* + * shdma_free_chan_resources - Free all resources of the channel. + */ +static void shdma_free_chan_resources(struct dma_chan *chan) +{ + struct shdma_chan *schan = to_shdma_chan(chan); + struct shdma_dev *sdev = to_shdma_dev(chan->device); + const struct shdma_ops *ops = sdev->ops; + LIST_HEAD(list); + + /* Protect against ISR */ + spin_lock_irq(&schan->chan_lock); + ops->halt_channel(schan); + spin_unlock_irq(&schan->chan_lock); + + /* Now no new interrupts will occur */ + + /* Prepared and not submitted descriptors can still be on the queue */ + if (!list_empty(&schan->ld_queue)) + shdma_chan_ld_cleanup(schan, true); + + if (chan->private) { + /* The caller is holding dma_list_mutex */ + struct shdma_slave *slave = chan->private; + clear_bit(slave->slave_id, shdma_slave_used); + chan->private = NULL; + } + + spin_lock_irq(&schan->chan_lock); + + list_splice_init(&schan->ld_free, &list); + schan->desc_num = 0; + + spin_unlock_irq(&schan->chan_lock); + + kfree(schan->desc); +} + +/** + * shdma_add_desc - get, set up and return one transfer descriptor + * @schan: DMA channel + * @flags: DMA transfer flags + * @dst: destination DMA address, incremented when direction equals + * DMA_DEV_TO_MEM or DMA_MEM_TO_MEM + * @src: source DMA address, incremented when direction equals + * DMA_MEM_TO_DEV or DMA_MEM_TO_MEM + * @len: DMA transfer length + * @first: if NULL, set to the current descriptor and cookie set to -EBUSY + * @direction: needed for slave DMA to decide which address to keep constant, + * equals DMA_MEM_TO_MEM for MEMCPY + * Returns 0 or an error + * Locks: called with desc_lock held + */ +static struct shdma_desc *shdma_add_desc(struct shdma_chan *schan, + unsigned long flags, dma_addr_t *dst, dma_addr_t *src, size_t *len, + struct shdma_desc **first, enum dma_transfer_direction direction) +{ + struct shdma_dev *sdev = to_shdma_dev(schan->dma_chan.device); + const struct shdma_ops *ops = sdev->ops; + struct shdma_desc *new; + size_t copy_size = *len; + + if (!copy_size) + return NULL; + + /* Allocate the link descriptor from the free list */ + new = shdma_get_desc(schan); + if (!new) { + dev_err(schan->dev, "No free link descriptor available\n"); + return NULL; + } + + ops->desc_setup(schan, new, *src, *dst, ©_size); + + if (!*first) { + /* First desc */ + new->async_tx.cookie = -EBUSY; + *first = new; + } else { + /* Other desc - invisible to the user */ + new->async_tx.cookie = -EINVAL; + } + + dev_dbg(schan->dev, + "chaining (%u/%u)@%x -> %x with %p, cookie %d\n", + copy_size, *len, *src, *dst, &new->async_tx, + new->async_tx.cookie); + + new->mark = DESC_PREPARED; + new->async_tx.flags = flags; + new->direction = direction; + + *len -= copy_size; + if (direction == DMA_MEM_TO_MEM || direction == DMA_MEM_TO_DEV) + *src += copy_size; + if (direction == DMA_MEM_TO_MEM || direction == DMA_DEV_TO_MEM) + *dst += copy_size; + + return new; +} + +/* + * shdma_prep_sg - prepare transfer descriptors from an SG list + * + * Common routine for public (MEMCPY) and slave DMA. The MEMCPY case is also + * converted to scatter-gather to guarantee consistent locking and a correct + * list manipulation. For slave DMA direction carries the usual meaning, and, + * logically, the SG list is RAM and the addr variable contains slave address, + * e.g., the FIFO I/O register. For MEMCPY direction equals DMA_MEM_TO_MEM + * and the SG list contains only one element and points at the source buffer. + */ +static struct dma_async_tx_descriptor *shdma_prep_sg(struct shdma_chan *schan, + struct scatterlist *sgl, unsigned int sg_len, dma_addr_t *addr, + enum dma_transfer_direction direction, unsigned long flags) +{ + struct scatterlist *sg; + struct shdma_desc *first = NULL, *new = NULL /* compiler... */; + LIST_HEAD(tx_list); + int chunks = 0; + unsigned long irq_flags; + int i; + + for_each_sg(sgl, sg, sg_len, i) + chunks += DIV_ROUND_UP(sg_dma_len(sg), schan->max_xfer_len); + + /* Have to lock the whole loop to protect against concurrent release */ + spin_lock_irqsave(&schan->chan_lock, irq_flags); + + /* + * Chaining: + * first descriptor is what user is dealing with in all API calls, its + * cookie is at first set to -EBUSY, at tx-submit to a positive + * number + * if more than one chunk is needed further chunks have cookie = -EINVAL + * the last chunk, if not equal to the first, has cookie = -ENOSPC + * all chunks are linked onto the tx_list head with their .node heads + * only during this function, then they are immediately spliced + * back onto the free list in form of a chain + */ + for_each_sg(sgl, sg, sg_len, i) { + dma_addr_t sg_addr = sg_dma_address(sg); + size_t len = sg_dma_len(sg); + + if (!len) + goto err_get_desc; + + do { + dev_dbg(schan->dev, "Add SG #%d@%p[%d], dma %llx\n", + i, sg, len, (unsigned long long)sg_addr); + + if (direction == DMA_DEV_TO_MEM) + new = shdma_add_desc(schan, flags, + &sg_addr, addr, &len, &first, + direction); + else + new = shdma_add_desc(schan, flags, + addr, &sg_addr, &len, &first, + direction); + if (!new) + goto err_get_desc; + + new->chunks = chunks--; + list_add_tail(&new->node, &tx_list); + } while (len); + } + + if (new != first) + new->async_tx.cookie = -ENOSPC; + + /* Put them back on the free list, so, they don't get lost */ + list_splice_tail(&tx_list, &schan->ld_free); + + spin_unlock_irqrestore(&schan->chan_lock, irq_flags); + + return &first->async_tx; + +err_get_desc: + list_for_each_entry(new, &tx_list, node) + new->mark = DESC_IDLE; + list_splice(&tx_list, &schan->ld_free); + + spin_unlock_irqrestore(&schan->chan_lock, irq_flags); + + return NULL; +} + +static struct dma_async_tx_descriptor *shdma_prep_memcpy( + struct dma_chan *chan, dma_addr_t dma_dest, dma_addr_t dma_src, + size_t len, unsigned long flags) +{ + struct shdma_chan *schan = to_shdma_chan(chan); + struct scatterlist sg; + + if (!chan || !len) + return NULL; + + BUG_ON(!schan->desc_num); + + sg_init_table(&sg, 1); + sg_set_page(&sg, pfn_to_page(PFN_DOWN(dma_src)), len, + offset_in_page(dma_src)); + sg_dma_address(&sg) = dma_src; + sg_dma_len(&sg) = len; + + return shdma_prep_sg(schan, &sg, 1, &dma_dest, DMA_MEM_TO_MEM, flags); +} + +static struct dma_async_tx_descriptor *shdma_prep_slave_sg( + struct dma_chan *chan, struct scatterlist *sgl, unsigned int sg_len, + enum dma_transfer_direction direction, unsigned long flags, void *context) +{ + struct shdma_chan *schan = to_shdma_chan(chan); + struct shdma_dev *sdev = to_shdma_dev(schan->dma_chan.device); + const struct shdma_ops *ops = sdev->ops; + struct shdma_slave *slave = chan->private; + dma_addr_t slave_addr; + + if (!chan) + return NULL; + + BUG_ON(!schan->desc_num); + + /* Someone calling slave DMA on a generic channel? */ + if (!slave || !sg_len) { + dev_warn(schan->dev, "%s: bad parameter: %p, %d, %d\n", + __func__, slave, sg_len, slave ? slave->slave_id : -1); + return NULL; + } + + slave_addr = ops->slave_addr(schan); + + return shdma_prep_sg(schan, sgl, sg_len, &slave_addr, + direction, flags); +} + +static int shdma_control(struct dma_chan *chan, enum dma_ctrl_cmd cmd, + unsigned long arg) +{ + struct shdma_chan *schan = to_shdma_chan(chan); + struct shdma_dev *sdev = to_shdma_dev(chan->device); + const struct shdma_ops *ops = sdev->ops; + unsigned long flags; + + /* Only supports DMA_TERMINATE_ALL */ + if (cmd != DMA_TERMINATE_ALL) + return -ENXIO; + + if (!chan) + return -EINVAL; + + spin_lock_irqsave(&schan->chan_lock, flags); + + ops->halt_channel(schan); + + spin_unlock_irqrestore(&schan->chan_lock, flags); + + shdma_chan_ld_cleanup(schan, true); + + return 0; +} + +static void shdma_issue_pending(struct dma_chan *chan) +{ + struct shdma_chan *schan = to_shdma_chan(chan); + + spin_lock_irq(&schan->chan_lock); + if (schan->pm_state == SHDMA_PM_ESTABLISHED) + shdma_chan_xfer_ld_queue(schan); + else + schan->pm_state = SHDMA_PM_PENDING; + spin_unlock_irq(&schan->chan_lock); +} + +static enum dma_status shdma_tx_status(struct dma_chan *chan, + dma_cookie_t cookie, + struct dma_tx_state *txstate) +{ + struct shdma_chan *schan = to_shdma_chan(chan); + enum dma_status status; + unsigned long flags; + + shdma_chan_ld_cleanup(schan, false); + + spin_lock_irqsave(&schan->chan_lock, flags); + + status = dma_cookie_status(chan, cookie, txstate); + + /* + * If we don't find cookie on the queue, it has been aborted and we have + * to report error + */ + if (status != DMA_SUCCESS) { + struct shdma_desc *sdesc; + status = DMA_ERROR; + list_for_each_entry(sdesc, &schan->ld_queue, node) + if (sdesc->cookie == cookie) { + status = DMA_IN_PROGRESS; + break; + } + } + + spin_unlock_irqrestore(&schan->chan_lock, flags); + + return status; +} + +/* Called from error IRQ or NMI */ +bool shdma_reset(struct shdma_dev *sdev) +{ + const struct shdma_ops *ops = sdev->ops; + struct shdma_chan *schan; + unsigned int handled = 0; + int i; + + /* Reset all channels */ + shdma_for_each_chan(schan, sdev, i) { + struct shdma_desc *sdesc; + LIST_HEAD(dl); + + if (!schan) + continue; + + spin_lock(&schan->chan_lock); + + /* Stop the channel */ + ops->halt_channel(schan); + + list_splice_init(&schan->ld_queue, &dl); + + if (!list_empty(&dl)) { + dev_dbg(schan->dev, "Bring down channel %d\n", schan->id); + pm_runtime_put(schan->dev); + } + schan->pm_state = SHDMA_PM_ESTABLISHED; + + spin_unlock(&schan->chan_lock); + + /* Complete all */ + list_for_each_entry(sdesc, &dl, node) { + struct dma_async_tx_descriptor *tx = &sdesc->async_tx; + sdesc->mark = DESC_IDLE; + if (tx->callback) + tx->callback(tx->callback_param); + } + + spin_lock(&schan->chan_lock); + list_splice(&dl, &schan->ld_free); + spin_unlock(&schan->chan_lock); + + handled++; + } + + return !!handled; +} +EXPORT_SYMBOL(shdma_reset); + +static irqreturn_t chan_irq(int irq, void *dev) +{ + struct shdma_chan *schan = dev; + const struct shdma_ops *ops = + to_shdma_dev(schan->dma_chan.device)->ops; + irqreturn_t ret; + + spin_lock(&schan->chan_lock); + + ret = ops->chan_irq(schan, irq) ? IRQ_WAKE_THREAD : IRQ_NONE; + + spin_unlock(&schan->chan_lock); + + return ret; +} + +static irqreturn_t chan_irqt(int irq, void *dev) +{ + struct shdma_chan *schan = dev; + const struct shdma_ops *ops = + to_shdma_dev(schan->dma_chan.device)->ops; + struct shdma_desc *sdesc; + + spin_lock_irq(&schan->chan_lock); + list_for_each_entry(sdesc, &schan->ld_queue, node) { + if (sdesc->mark == DESC_SUBMITTED && + ops->desc_completed(schan, sdesc)) { + dev_dbg(schan->dev, "done #%d@%p\n", + sdesc->async_tx.cookie, &sdesc->async_tx); + sdesc->mark = DESC_COMPLETED; + break; + } + } + /* Next desc */ + shdma_chan_xfer_ld_queue(schan); + spin_unlock_irq(&schan->chan_lock); + + shdma_chan_ld_cleanup(schan, false); + + return IRQ_HANDLED; +} + +int shdma_request_irq(struct shdma_chan *schan, int irq, + unsigned long flags, const char *name) +{ + int ret = request_threaded_irq(irq, chan_irq, chan_irqt, + flags, name, schan); + + schan->irq = ret < 0 ? ret : irq; + + return ret; +} +EXPORT_SYMBOL(shdma_request_irq); + +void shdma_free_irq(struct shdma_chan *schan) +{ + if (schan->irq >= 0) + free_irq(schan->irq, schan); +} +EXPORT_SYMBOL(shdma_free_irq); + +void shdma_chan_probe(struct shdma_dev *sdev, + struct shdma_chan *schan, int id) +{ + schan->pm_state = SHDMA_PM_ESTABLISHED; + + /* reference struct dma_device */ + schan->dma_chan.device = &sdev->dma_dev; + dma_cookie_init(&schan->dma_chan); + + schan->dev = sdev->dma_dev.dev; + schan->id = id; + + if (!schan->max_xfer_len) + schan->max_xfer_len = PAGE_SIZE; + + spin_lock_init(&schan->chan_lock); + + /* Init descripter manage list */ + INIT_LIST_HEAD(&schan->ld_queue); + INIT_LIST_HEAD(&schan->ld_free); + + /* Add the channel to DMA device channel list */ + list_add_tail(&schan->dma_chan.device_node, + &sdev->dma_dev.channels); + sdev->schan[sdev->dma_dev.chancnt++] = schan; +} +EXPORT_SYMBOL(shdma_chan_probe); + +void shdma_chan_remove(struct shdma_chan *schan) +{ + list_del(&schan->dma_chan.device_node); +} +EXPORT_SYMBOL(shdma_chan_remove); + +int shdma_init(struct device *dev, struct shdma_dev *sdev, + int chan_num) +{ + struct dma_device *dma_dev = &sdev->dma_dev; + + /* + * Require all call-backs for now, they can trivially be made optional + * later as required + */ + if (!sdev->ops || + !sdev->desc_size || + !sdev->ops->embedded_desc || + !sdev->ops->start_xfer || + !sdev->ops->setup_xfer || + !sdev->ops->set_slave || + !sdev->ops->desc_setup || + !sdev->ops->slave_addr || + !sdev->ops->channel_busy || + !sdev->ops->halt_channel || + !sdev->ops->desc_completed) + return -EINVAL; + + sdev->schan = kcalloc(chan_num, sizeof(*sdev->schan), GFP_KERNEL); + if (!sdev->schan) + return -ENOMEM; + + INIT_LIST_HEAD(&dma_dev->channels); + + /* Common and MEMCPY operations */ + dma_dev->device_alloc_chan_resources + = shdma_alloc_chan_resources; + dma_dev->device_free_chan_resources = shdma_free_chan_resources; + dma_dev->device_prep_dma_memcpy = shdma_prep_memcpy; + dma_dev->device_tx_status = shdma_tx_status; + dma_dev->device_issue_pending = shdma_issue_pending; + + /* Compulsory for DMA_SLAVE fields */ + dma_dev->device_prep_slave_sg = shdma_prep_slave_sg; + dma_dev->device_control = shdma_control; + + dma_dev->dev = dev; + + return 0; +} +EXPORT_SYMBOL(shdma_init); + +void shdma_cleanup(struct shdma_dev *sdev) +{ + kfree(sdev->schan); +} +EXPORT_SYMBOL(shdma_cleanup); + +static int __init shdma_enter(void) +{ + shdma_slave_used = kzalloc(DIV_ROUND_UP(slave_num, BITS_PER_LONG) * + sizeof(long), GFP_KERNEL); + if (!shdma_slave_used) + return -ENOMEM; + return 0; +} +module_init(shdma_enter); + +static void __exit shdma_exit(void) +{ + kfree(shdma_slave_used); +} +module_exit(shdma_exit); + +MODULE_LICENSE("GPL v2"); +MODULE_DESCRIPTION("SH-DMA driver base library"); +MODULE_AUTHOR("Guennadi Liakhovetski "); -- cgit v1.2.3 From ecf90fbbdc66cde6f5fa25d88541112b9baac459 Mon Sep 17 00:00:00 2001 From: Guennadi Liakhovetski Date: Thu, 5 Jul 2012 12:29:40 +0200 Subject: dmaengine: shdma: prepare to stop using struct dma_chan::private Using struct dma_chan::private is deprecated. To update the shdma driver to stop using it we first have to eliminate internal runtime uses of it. After that we will also be able to stop using it for channel configuration. Signed-off-by: Guennadi Liakhovetski Signed-off-by: Vinod Koul --- drivers/dma/sh/shdma-base.c | 9 +++++---- drivers/dma/sh/shdma.c | 24 ++++++++++-------------- drivers/dma/sh/shdma.h | 2 ++ include/linux/sh_dma.h | 2 -- include/linux/shdma-base.h | 1 + 5 files changed, 18 insertions(+), 20 deletions(-) (limited to 'drivers/dma/sh/shdma-base.c') diff --git a/drivers/dma/sh/shdma-base.c b/drivers/dma/sh/shdma-base.c index ff060d0da908..f75ebfa735c0 100644 --- a/drivers/dma/sh/shdma-base.c +++ b/drivers/dma/sh/shdma-base.c @@ -76,7 +76,7 @@ static dma_cookie_t shdma_tx_submit(struct dma_async_tx_descriptor *tx) container_of(tx, struct shdma_desc, async_tx), *last = desc; struct shdma_chan *schan = to_shdma_chan(tx->chan); - struct shdma_slave *slave = tx->chan->private; + struct shdma_slave *slave = schan->slave; dma_async_tx_callback callback = tx->callback; dma_cookie_t cookie; bool power_up; @@ -208,6 +208,7 @@ static int shdma_alloc_chan_resources(struct dma_chan *chan) goto edescalloc; } schan->desc_num = NR_DESCS_PER_CHANNEL; + schan->slave = slave; for (i = 0; i < NR_DESCS_PER_CHANNEL; i++) { desc = ops->embedded_desc(schan->desc, i); @@ -365,9 +366,9 @@ static void shdma_free_chan_resources(struct dma_chan *chan) if (!list_empty(&schan->ld_queue)) shdma_chan_ld_cleanup(schan, true); - if (chan->private) { + if (schan->slave) { /* The caller is holding dma_list_mutex */ - struct shdma_slave *slave = chan->private; + struct shdma_slave *slave = schan->slave; clear_bit(slave->slave_id, shdma_slave_used); chan->private = NULL; } @@ -558,7 +559,7 @@ static struct dma_async_tx_descriptor *shdma_prep_slave_sg( struct shdma_chan *schan = to_shdma_chan(chan); struct shdma_dev *sdev = to_shdma_dev(schan->dma_chan.device); const struct shdma_ops *ops = sdev->ops; - struct shdma_slave *slave = chan->private; + struct shdma_slave *slave = schan->slave; dma_addr_t slave_addr; if (!chan) diff --git a/drivers/dma/sh/shdma.c b/drivers/dma/sh/shdma.c index f06906f281ac..9f0a2e507ac3 100644 --- a/drivers/dma/sh/shdma.c +++ b/drivers/dma/sh/shdma.c @@ -291,10 +291,8 @@ static void sh_dmae_setup_xfer(struct shdma_chan *schan, shdma_chan); if (sslave) { - struct sh_dmae_slave *slave = container_of(sslave, - struct sh_dmae_slave, shdma_slave); const struct sh_dmae_slave_config *cfg = - slave->config; + sh_chan->config; dmae_set_dmars(sh_chan, cfg->mid_rid); dmae_set_chcr(sh_chan, cfg->chcr); @@ -326,13 +324,11 @@ static int sh_dmae_set_slave(struct shdma_chan *schan, { struct sh_dmae_chan *sh_chan = container_of(schan, struct sh_dmae_chan, shdma_chan); - struct sh_dmae_slave *slave = container_of(sslave, struct sh_dmae_slave, - shdma_slave); const struct sh_dmae_slave_config *cfg = dmae_find_slave(sh_chan, sslave->slave_id); if (!cfg) return -ENODEV; - slave->config = cfg; + sh_chan->config = cfg; return 0; } @@ -579,13 +575,12 @@ static int sh_dmae_resume(struct device *dev) for (i = 0; i < shdev->pdata->channel_num; i++) { struct sh_dmae_chan *sh_chan = shdev->chan[i]; - struct sh_dmae_slave *param = sh_chan->shdma_chan.dma_chan.private; if (!sh_chan->shdma_chan.desc_num) continue; - if (param) { - const struct sh_dmae_slave_config *cfg = param->config; + if (sh_chan->shdma_chan.slave) { + const struct sh_dmae_slave_config *cfg = sh_chan->config; dmae_set_dmars(sh_chan, cfg->mid_rid); dmae_set_chcr(sh_chan, cfg->chcr); } else { @@ -609,14 +604,15 @@ const struct dev_pm_ops sh_dmae_pm = { static dma_addr_t sh_dmae_slave_addr(struct shdma_chan *schan) { - struct sh_dmae_slave *param = schan->dma_chan.private; + struct sh_dmae_chan *sh_chan = container_of(schan, + struct sh_dmae_chan, shdma_chan); /* - * Implicit BUG_ON(!param) - * if (param != NULL), this is a successfully requested slave channel, - * therefore param->config != NULL too. + * Implicit BUG_ON(!sh_chan->config) + * This is an exclusive slave DMA operation, may only be called after a + * successful slave configuration. */ - return param->config->addr; + return sh_chan->config->addr; } static struct shdma_desc *sh_dmae_embedded_desc(void *buf, int i) diff --git a/drivers/dma/sh/shdma.h b/drivers/dma/sh/shdma.h index 840e47d1c86c..9314e93225db 100644 --- a/drivers/dma/sh/shdma.h +++ b/drivers/dma/sh/shdma.h @@ -13,6 +13,7 @@ #ifndef __DMA_SHDMA_H #define __DMA_SHDMA_H +#include #include #include #include @@ -25,6 +26,7 @@ struct device; struct sh_dmae_chan { struct shdma_chan shdma_chan; + const struct sh_dmae_slave_config *config; /* Slave DMA configuration */ int xmit_shift; /* log_2(bytes_per_xfer) */ u32 __iomem *base; char dev_id[16]; /* unique name per DMAC of channel */ diff --git a/include/linux/sh_dma.h b/include/linux/sh_dma.h index 7c8ca41e60e6..a79f10a32243 100644 --- a/include/linux/sh_dma.h +++ b/include/linux/sh_dma.h @@ -20,8 +20,6 @@ struct device; /* Used by slave DMA clients to request DMA to/from a specific peripheral */ struct sh_dmae_slave { struct shdma_slave shdma_slave; /* Set by the platform */ - struct device *dma_dev; /* Set by the platform */ - const struct sh_dmae_slave_config *config; /* Set by the driver */ }; /* diff --git a/include/linux/shdma-base.h b/include/linux/shdma-base.h index 83efd1332b39..c3a19e9c20c4 100644 --- a/include/linux/shdma-base.h +++ b/include/linux/shdma-base.h @@ -66,6 +66,7 @@ struct shdma_chan { size_t max_xfer_len; /* max transfer length */ int id; /* Raw id of this channel */ int irq; /* Channel IRQ */ + struct shdma_slave *slave; /* Client data for slave DMA */ enum shdma_pm_state pm_state; }; -- cgit v1.2.3 From c2cdb7e4d16394fc51dc5c2c5b3e7c3733bdfaac Mon Sep 17 00:00:00 2001 From: Guennadi Liakhovetski Date: Thu, 5 Jul 2012 12:29:41 +0200 Subject: dma: sh: use an integer slave ID to improve API compatibility Initially struct shdma_slave has been introduced with the only member - an unsigned slave ID - to describe common properties of DMA slaves in an extensible way. However, experience shows, that a slave ID is indeed the only parameter, needed to identify DMA slaves. This is also, what is used by the core dmaengine API in struct dma_slave_config. We switch to using the slave_id directly, instead of passing a pointer to struct shdma_slave to improve compatibility with the core. We also make the slave_id signed for easier error checking. Signed-off-by: Guennadi Liakhovetski Signed-off-by: Vinod Koul --- drivers/dma/sh/shdma-base.c | 25 +++++++++++++------------ drivers/dma/sh/shdma.c | 12 ++++++------ include/linux/sh_dma.h | 8 ++++---- include/linux/shdma-base.h | 8 ++++---- 4 files changed, 27 insertions(+), 26 deletions(-) (limited to 'drivers/dma/sh/shdma-base.c') diff --git a/drivers/dma/sh/shdma-base.c b/drivers/dma/sh/shdma-base.c index f75ebfa735c0..73db282a1436 100644 --- a/drivers/dma/sh/shdma-base.c +++ b/drivers/dma/sh/shdma-base.c @@ -76,7 +76,6 @@ static dma_cookie_t shdma_tx_submit(struct dma_async_tx_descriptor *tx) container_of(tx, struct shdma_desc, async_tx), *last = desc; struct shdma_chan *schan = to_shdma_chan(tx->chan); - struct shdma_slave *slave = schan->slave; dma_async_tx_callback callback = tx->callback; dma_cookie_t cookie; bool power_up; @@ -138,7 +137,7 @@ static dma_cookie_t shdma_tx_submit(struct dma_async_tx_descriptor *tx) * Make it int then, on error remove chunks from the * queue again */ - ops->setup_xfer(schan, slave); + ops->setup_xfer(schan, schan->slave_id); if (schan->pm_state == SHDMA_PM_PENDING) shdma_chan_xfer_ld_queue(schan); @@ -186,7 +185,7 @@ static int shdma_alloc_chan_resources(struct dma_chan *chan) * never runs concurrently with itself or free_chan_resources. */ if (slave) { - if (slave->slave_id >= slave_num) { + if (slave->slave_id < 0 || slave->slave_id >= slave_num) { ret = -EINVAL; goto evalid; } @@ -196,9 +195,13 @@ static int shdma_alloc_chan_resources(struct dma_chan *chan) goto etestused; } - ret = ops->set_slave(schan, slave); + ret = ops->set_slave(schan, slave->slave_id); if (ret < 0) goto esetslave; + + schan->slave_id = slave->slave_id; + } else { + schan->slave_id = -EINVAL; } schan->desc = kcalloc(NR_DESCS_PER_CHANNEL, @@ -208,7 +211,6 @@ static int shdma_alloc_chan_resources(struct dma_chan *chan) goto edescalloc; } schan->desc_num = NR_DESCS_PER_CHANNEL; - schan->slave = slave; for (i = 0; i < NR_DESCS_PER_CHANNEL; i++) { desc = ops->embedded_desc(schan->desc, i); @@ -366,10 +368,9 @@ static void shdma_free_chan_resources(struct dma_chan *chan) if (!list_empty(&schan->ld_queue)) shdma_chan_ld_cleanup(schan, true); - if (schan->slave) { + if (schan->slave_id >= 0) { /* The caller is holding dma_list_mutex */ - struct shdma_slave *slave = schan->slave; - clear_bit(slave->slave_id, shdma_slave_used); + clear_bit(schan->slave_id, shdma_slave_used); chan->private = NULL; } @@ -559,7 +560,7 @@ static struct dma_async_tx_descriptor *shdma_prep_slave_sg( struct shdma_chan *schan = to_shdma_chan(chan); struct shdma_dev *sdev = to_shdma_dev(schan->dma_chan.device); const struct shdma_ops *ops = sdev->ops; - struct shdma_slave *slave = schan->slave; + int slave_id = schan->slave_id; dma_addr_t slave_addr; if (!chan) @@ -568,9 +569,9 @@ static struct dma_async_tx_descriptor *shdma_prep_slave_sg( BUG_ON(!schan->desc_num); /* Someone calling slave DMA on a generic channel? */ - if (!slave || !sg_len) { - dev_warn(schan->dev, "%s: bad parameter: %p, %d, %d\n", - __func__, slave, sg_len, slave ? slave->slave_id : -1); + if (slave_id < 0 || !sg_len) { + dev_warn(schan->dev, "%s: bad parameter: len=%d, id=%d\n", + __func__, sg_len, slave_id); return NULL; } diff --git a/drivers/dma/sh/shdma.c b/drivers/dma/sh/shdma.c index 9f0a2e507ac3..9a10d8bbdef2 100644 --- a/drivers/dma/sh/shdma.c +++ b/drivers/dma/sh/shdma.c @@ -285,12 +285,12 @@ static bool sh_dmae_channel_busy(struct shdma_chan *schan) } static void sh_dmae_setup_xfer(struct shdma_chan *schan, - struct shdma_slave *sslave) + int slave_id) { struct sh_dmae_chan *sh_chan = container_of(schan, struct sh_dmae_chan, shdma_chan); - if (sslave) { + if (slave_id >= 0) { const struct sh_dmae_slave_config *cfg = sh_chan->config; @@ -302,7 +302,7 @@ static void sh_dmae_setup_xfer(struct shdma_chan *schan, } static const struct sh_dmae_slave_config *dmae_find_slave( - struct sh_dmae_chan *sh_chan, unsigned int slave_id) + struct sh_dmae_chan *sh_chan, int slave_id) { struct sh_dmae_device *shdev = to_sh_dev(sh_chan); struct sh_dmae_pdata *pdata = shdev->pdata; @@ -320,11 +320,11 @@ static const struct sh_dmae_slave_config *dmae_find_slave( } static int sh_dmae_set_slave(struct shdma_chan *schan, - struct shdma_slave *sslave) + int slave_id) { struct sh_dmae_chan *sh_chan = container_of(schan, struct sh_dmae_chan, shdma_chan); - const struct sh_dmae_slave_config *cfg = dmae_find_slave(sh_chan, sslave->slave_id); + const struct sh_dmae_slave_config *cfg = dmae_find_slave(sh_chan, slave_id); if (!cfg) return -ENODEV; @@ -579,7 +579,7 @@ static int sh_dmae_resume(struct device *dev) if (!sh_chan->shdma_chan.desc_num) continue; - if (sh_chan->shdma_chan.slave) { + if (sh_chan->shdma_chan.slave_id >= 0) { const struct sh_dmae_slave_config *cfg = sh_chan->config; dmae_set_dmars(sh_chan, cfg->mid_rid); dmae_set_chcr(sh_chan, cfg->chcr); diff --git a/include/linux/sh_dma.h b/include/linux/sh_dma.h index a79f10a32243..4e83f3e034f3 100644 --- a/include/linux/sh_dma.h +++ b/include/linux/sh_dma.h @@ -27,10 +27,10 @@ struct sh_dmae_slave { * a certain peripheral */ struct sh_dmae_slave_config { - unsigned int slave_id; - dma_addr_t addr; - u32 chcr; - char mid_rid; + int slave_id; + dma_addr_t addr; + u32 chcr; + char mid_rid; }; struct sh_dmae_channel { diff --git a/include/linux/shdma-base.h b/include/linux/shdma-base.h index c3a19e9c20c4..6263ad2e7426 100644 --- a/include/linux/shdma-base.h +++ b/include/linux/shdma-base.h @@ -43,7 +43,7 @@ struct device; */ struct shdma_slave { - unsigned int slave_id; + int slave_id; }; struct shdma_desc { @@ -66,7 +66,7 @@ struct shdma_chan { size_t max_xfer_len; /* max transfer length */ int id; /* Raw id of this channel */ int irq; /* Channel IRQ */ - struct shdma_slave *slave; /* Client data for slave DMA */ + int slave_id; /* Client ID for slave DMA */ enum shdma_pm_state pm_state; }; @@ -93,8 +93,8 @@ struct shdma_ops { dma_addr_t (*slave_addr)(struct shdma_chan *); int (*desc_setup)(struct shdma_chan *, struct shdma_desc *, dma_addr_t, dma_addr_t, size_t *); - int (*set_slave)(struct shdma_chan *, struct shdma_slave *); - void (*setup_xfer)(struct shdma_chan *, struct shdma_slave *); + int (*set_slave)(struct shdma_chan *, int); + void (*setup_xfer)(struct shdma_chan *, int); void (*start_xfer)(struct shdma_chan *, struct shdma_desc *); struct shdma_desc *(*embedded_desc)(void *, int); bool (*chan_irq)(struct shdma_chan *, int); -- cgit v1.2.3 From 1ff8df4f5388ad66bd7d0199b5839a2e3345c055 Mon Sep 17 00:00:00 2001 From: Guennadi Liakhovetski Date: Thu, 5 Jul 2012 12:29:42 +0200 Subject: dma: sh: provide a migration path for slave drivers to stop using .private This patch extends the sh dmaengine driver to support the preferred channel selection and configuration method, instead of using the "private" field from struct dma_chan. We add a standard filter function to be used by slave drivers instead of implementing their own ones, and add support for the DMA_SLAVE_CONFIG control operation, which must accompany the new channel selection method. We still support the legacy .private channel allocation method to cater for a smooth driver migration. Signed-off-by: Guennadi Liakhovetski [applied a trvial checkpath fix] Signed-off-by: Vinod Koul --- drivers/dma/sh/shdma-base.c | 114 ++++++++++++++++++++++++++++++++++---------- drivers/dma/sh/shdma.c | 5 +- include/linux/sh_dma.h | 2 + include/linux/shdma-base.h | 2 +- 4 files changed, 95 insertions(+), 28 deletions(-) (limited to 'drivers/dma/sh/shdma-base.c') diff --git a/drivers/dma/sh/shdma-base.c b/drivers/dma/sh/shdma-base.c index 73db282a1436..27f5c781fd73 100644 --- a/drivers/dma/sh/shdma-base.c +++ b/drivers/dma/sh/shdma-base.c @@ -171,6 +171,65 @@ static struct shdma_desc *shdma_get_desc(struct shdma_chan *schan) return NULL; } +static int shdma_setup_slave(struct shdma_chan *schan, int slave_id) +{ + struct shdma_dev *sdev = to_shdma_dev(schan->dma_chan.device); + const struct shdma_ops *ops = sdev->ops; + int ret; + + if (slave_id < 0 || slave_id >= slave_num) + return -EINVAL; + + if (test_and_set_bit(slave_id, shdma_slave_used)) + return -EBUSY; + + ret = ops->set_slave(schan, slave_id, false); + if (ret < 0) { + clear_bit(slave_id, shdma_slave_used); + return ret; + } + + schan->slave_id = slave_id; + + return 0; +} + +/* + * This is the standard shdma filter function to be used as a replacement to the + * "old" method, using the .private pointer. If for some reason you allocate a + * channel without slave data, use something like ERR_PTR(-EINVAL) as a filter + * parameter. If this filter is used, the slave driver, after calling + * dma_request_channel(), will also have to call dmaengine_slave_config() with + * .slave_id, .direction, and either .src_addr or .dst_addr set. + * NOTE: this filter doesn't support multiple DMAC drivers with the DMA_SLAVE + * capability! If this becomes a requirement, hardware glue drivers, using this + * services would have to provide their own filters, which first would check + * the device driver, similar to how other DMAC drivers, e.g., sa11x0-dma.c, do + * this, and only then, in case of a match, call this common filter. + */ +bool shdma_chan_filter(struct dma_chan *chan, void *arg) +{ + struct shdma_chan *schan = to_shdma_chan(chan); + struct shdma_dev *sdev = to_shdma_dev(schan->dma_chan.device); + const struct shdma_ops *ops = sdev->ops; + int slave_id = (int)arg; + int ret; + + if (slave_id < 0) + /* No slave requested - arbitrary channel */ + return true; + + if (slave_id >= slave_num) + return false; + + ret = ops->set_slave(schan, slave_id, true); + if (ret < 0) + return false; + + return true; +} +EXPORT_SYMBOL(shdma_chan_filter); + static int shdma_alloc_chan_resources(struct dma_chan *chan) { struct shdma_chan *schan = to_shdma_chan(chan); @@ -185,21 +244,10 @@ static int shdma_alloc_chan_resources(struct dma_chan *chan) * never runs concurrently with itself or free_chan_resources. */ if (slave) { - if (slave->slave_id < 0 || slave->slave_id >= slave_num) { - ret = -EINVAL; - goto evalid; - } - - if (test_and_set_bit(slave->slave_id, shdma_slave_used)) { - ret = -EBUSY; - goto etestused; - } - - ret = ops->set_slave(schan, slave->slave_id); + /* Legacy mode: .private is set in filter */ + ret = shdma_setup_slave(schan, slave->slave_id); if (ret < 0) goto esetslave; - - schan->slave_id = slave->slave_id; } else { schan->slave_id = -EINVAL; } @@ -228,8 +276,6 @@ edescalloc: if (slave) esetslave: clear_bit(slave->slave_id, shdma_slave_used); -etestused: -evalid: chan->private = NULL; return ret; } @@ -587,22 +633,40 @@ static int shdma_control(struct dma_chan *chan, enum dma_ctrl_cmd cmd, struct shdma_chan *schan = to_shdma_chan(chan); struct shdma_dev *sdev = to_shdma_dev(chan->device); const struct shdma_ops *ops = sdev->ops; + struct dma_slave_config *config; unsigned long flags; - - /* Only supports DMA_TERMINATE_ALL */ - if (cmd != DMA_TERMINATE_ALL) - return -ENXIO; + int ret; if (!chan) return -EINVAL; - spin_lock_irqsave(&schan->chan_lock, flags); - - ops->halt_channel(schan); - - spin_unlock_irqrestore(&schan->chan_lock, flags); + switch (cmd) { + case DMA_TERMINATE_ALL: + spin_lock_irqsave(&schan->chan_lock, flags); + ops->halt_channel(schan); + spin_unlock_irqrestore(&schan->chan_lock, flags); - shdma_chan_ld_cleanup(schan, true); + shdma_chan_ld_cleanup(schan, true); + break; + case DMA_SLAVE_CONFIG: + /* + * So far only .slave_id is used, but the slave drivers are + * encouraged to also set a transfer direction and an address. + */ + if (!arg) + return -EINVAL; + /* + * We could lock this, but you shouldn't be configuring the + * channel, while using it... + */ + config = (struct dma_slave_config *)arg; + ret = shdma_setup_slave(schan, config->slave_id); + if (ret < 0) + return ret; + break; + default: + return -ENXIO; + } return 0; } diff --git a/drivers/dma/sh/shdma.c b/drivers/dma/sh/shdma.c index 9a10d8bbdef2..027c9be97654 100644 --- a/drivers/dma/sh/shdma.c +++ b/drivers/dma/sh/shdma.c @@ -320,7 +320,7 @@ static const struct sh_dmae_slave_config *dmae_find_slave( } static int sh_dmae_set_slave(struct shdma_chan *schan, - int slave_id) + int slave_id, bool try) { struct sh_dmae_chan *sh_chan = container_of(schan, struct sh_dmae_chan, shdma_chan); @@ -328,7 +328,8 @@ static int sh_dmae_set_slave(struct shdma_chan *schan, if (!cfg) return -ENODEV; - sh_chan->config = cfg; + if (!try) + sh_chan->config = cfg; return 0; } diff --git a/include/linux/sh_dma.h b/include/linux/sh_dma.h index 4e83f3e034f3..b64d6bec6f90 100644 --- a/include/linux/sh_dma.h +++ b/include/linux/sh_dma.h @@ -99,4 +99,6 @@ struct sh_dmae_pdata { #define CHCR_TE 0x00000002 #define CHCR_IE 0x00000004 +bool shdma_chan_filter(struct dma_chan *chan, void *arg); + #endif diff --git a/include/linux/shdma-base.h b/include/linux/shdma-base.h index 6263ad2e7426..93f9821554b6 100644 --- a/include/linux/shdma-base.h +++ b/include/linux/shdma-base.h @@ -93,7 +93,7 @@ struct shdma_ops { dma_addr_t (*slave_addr)(struct shdma_chan *); int (*desc_setup)(struct shdma_chan *, struct shdma_desc *, dma_addr_t, dma_addr_t, size_t *); - int (*set_slave)(struct shdma_chan *, int); + int (*set_slave)(struct shdma_chan *, int, bool); void (*setup_xfer)(struct shdma_chan *, int); void (*start_xfer)(struct shdma_chan *, struct shdma_desc *); struct shdma_desc *(*embedded_desc)(void *, int); -- cgit v1.2.3