From c2cdb7e4d16394fc51dc5c2c5b3e7c3733bdfaac Mon Sep 17 00:00:00 2001 From: Guennadi Liakhovetski Date: Thu, 5 Jul 2012 12:29:41 +0200 Subject: [PATCH] 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(-) 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); -- 2.20.1