On Wed, 2015-07-08 at 12:34 +0300, Andy Shevchenko wrote:
> All hardware accesses are done under virtual channel lock. That's why
> specific
> channel lock is excessive and can be removed safely. This has been
> tested on
> Intel Medfield and Merrifield.
Please, ignore this.
It's an old version.
>
> Signed-off-by: Andy Shevchenko <andriy.shevchenko@xxxxxxxxxxxxxxx>
> ---
> drivers/dma/hsu/hsu.c | 52 +++--------------------------------------
> ----------
> drivers/dma/hsu/hsu.h | 1 -
> 2 files changed, 3 insertions(+), 50 deletions(-)
>
> diff --git a/drivers/dma/hsu/hsu.c b/drivers/dma/hsu/hsu.c
> index f42f71e..729bcc9 100644
> --- a/drivers/dma/hsu/hsu.c
> +++ b/drivers/dma/hsu/hsu.c
> @@ -99,21 +99,13 @@ static void hsu_dma_chan_start(struct
> hsu_dma_chan *hsuc)
>
> static void hsu_dma_stop_channel(struct hsu_dma_chan *hsuc)
> {
> - unsigned long flags;
> -
> - spin_lock_irqsave(&hsuc->lock, flags);
> hsu_chan_disable(hsuc);
> hsu_chan_writel(hsuc, HSU_CH_DCR, 0);
> - spin_unlock_irqrestore(&hsuc->lock, flags);
> }
>
> static void hsu_dma_start_channel(struct hsu_dma_chan *hsuc)
> {
> - unsigned long flags;
> -
> - spin_lock_irqsave(&hsuc->lock, flags);
> hsu_dma_chan_start(hsuc);
> - spin_unlock_irqrestore(&hsuc->lock, flags);
> }
>
> static void hsu_dma_start_transfer(struct hsu_dma_chan *hsuc)
> @@ -134,23 +126,10 @@ static void hsu_dma_start_transfer(struct
> hsu_dma_chan *hsuc)
> hsu_dma_start_channel(hsuc);
> }
>
> -static u32 hsu_dma_chan_get_sr(struct hsu_dma_chan *hsuc)
> -{
> - unsigned long flags;
> - u32 sr;
> -
> - spin_lock_irqsave(&hsuc->lock, flags);
> - sr = hsu_chan_readl(hsuc, HSU_CH_SR);
> - spin_unlock_irqrestore(&hsuc->lock, flags);
> -
> - return sr;
> -}
> -
> irqreturn_t hsu_dma_irq(struct hsu_dma_chip *chip, unsigned short
> nr)
> {
> struct hsu_dma_chan *hsuc;
> struct hsu_dma_desc *desc;
> - unsigned long flags;
> u32 sr;
>
> /* Sanity check */
> @@ -163,7 +142,7 @@ irqreturn_t hsu_dma_irq(struct hsu_dma_chip
> *chip, unsigned short nr)
> * No matter what situation, need read clear the IRQ status
> * There is a bug, see Errata 5, HSD 2900918
> */
> - sr = hsu_dma_chan_get_sr(hsuc);
> + sr = hsu_chan_readl(hsuc, HSU_CH_SR);
> if (!sr)
> return IRQ_NONE;
>
> @@ -175,7 +154,6 @@ irqreturn_t hsu_dma_irq(struct hsu_dma_chip
> *chip, unsigned short nr)
> if (!sr)
> return IRQ_HANDLED;
>
> - spin_lock_irqsave(&hsuc->vchan.lock, flags);
> desc = hsuc->desc;
> if (desc) {
> if (sr & HSU_CH_SR_CHE) {
> @@ -188,7 +166,6 @@ irqreturn_t hsu_dma_irq(struct hsu_dma_chip
> *chip, unsigned short nr)
> hsu_dma_start_transfer(hsuc);
> }
> }
> - spin_unlock_irqrestore(&hsuc->vchan.lock, flags);
>
> return IRQ_HANDLED;
> }
> @@ -273,14 +250,11 @@ static size_t hsu_dma_active_desc_size(struct
> hsu_dma_chan *hsuc)
> struct hsu_dma_desc *desc = hsuc->desc;
> size_t bytes = hsu_dma_desc_size(desc);
> int i;
> - unsigned long flags;
>
> - spin_lock_irqsave(&hsuc->lock, flags);
> i = desc->active % HSU_DMA_CHAN_NR_DESC;
> do {
> bytes += hsu_chan_readl(hsuc, HSU_CH_DxTSR(i));
> } while (--i >= 0);
> - spin_unlock_irqrestore(&hsuc->lock, flags);
>
> return bytes;
> }
> @@ -327,24 +301,6 @@ static int hsu_dma_slave_config(struct dma_chan
> *chan,
> return 0;
> }
>
> -static void hsu_dma_chan_deactivate(struct hsu_dma_chan *hsuc)
> -{
> - unsigned long flags;
> -
> - spin_lock_irqsave(&hsuc->lock, flags);
> - hsu_chan_disable(hsuc);
> - spin_unlock_irqrestore(&hsuc->lock, flags);
> -}
> -
> -static void hsu_dma_chan_activate(struct hsu_dma_chan *hsuc)
> -{
> - unsigned long flags;
> -
> - spin_lock_irqsave(&hsuc->lock, flags);
> - hsu_chan_enable(hsuc);
> - spin_unlock_irqrestore(&hsuc->lock, flags);
> -}
> -
> static int hsu_dma_pause(struct dma_chan *chan)
> {
> struct hsu_dma_chan *hsuc = to_hsu_dma_chan(chan);
> @@ -352,7 +308,7 @@ static int hsu_dma_pause(struct dma_chan *chan)
>
> spin_lock_irqsave(&hsuc->vchan.lock, flags);
> if (hsuc->desc && hsuc->desc->status == DMA_IN_PROGRESS) {
> - hsu_dma_chan_deactivate(hsuc);
> + hsu_chan_disable(hsuc);
> hsuc->desc->status = DMA_PAUSED;
> }
> spin_unlock_irqrestore(&hsuc->vchan.lock, flags);
> @@ -368,7 +324,7 @@ static int hsu_dma_resume(struct dma_chan *chan)
> spin_lock_irqsave(&hsuc->vchan.lock, flags);
> if (hsuc->desc && hsuc->desc->status == DMA_PAUSED) {
> hsuc->desc->status = DMA_IN_PROGRESS;
> - hsu_dma_chan_activate(hsuc);
> + hsu_chan_enable(hsuc);
> }
> spin_unlock_irqrestore(&hsuc->vchan.lock, flags);
>
> @@ -441,8 +397,6 @@ int hsu_dma_probe(struct hsu_dma_chip *chip)
>
> hsuc->direction = (i & 0x1) ? DMA_DEV_TO_MEM :
> DMA_MEM_TO_DEV;
> hsuc->reg = addr + i * HSU_DMA_CHAN_LENGTH;
> -
> - spin_lock_init(&hsuc->lock);
> }
>
> dma_cap_set(DMA_SLAVE, hsu->dma.cap_mask);
> diff --git a/drivers/dma/hsu/hsu.h b/drivers/dma/hsu/hsu.h
> index 0275233..eeb9fff 100644
> --- a/drivers/dma/hsu/hsu.h
> +++ b/drivers/dma/hsu/hsu.h
> @@ -78,7 +78,6 @@ struct hsu_dma_chan {
> struct virt_dma_chan vchan;
>
> void __iomem *reg;
> - spinlock_t lock;
>
> /* hardware configuration */
> enum dma_transfer_direction direction;
--
Andy Shevchenko <andriy.shevchenko@xxxxxxxxxxxxxxx>
Intel Finland Oy
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