On Thu, 2014-10-16 at 12:17 +0200, Maxime Ripard wrote:
> Split the device_control callback of the DesignWare DMA driver to make use
> of the newly introduced callbacks, that will eventually be used to retrieve
> slave capabilities.
I will look at the main patches in the series later, but now I would
like to comment this one.
>
> Signed-off-by: Maxime Ripard <maxime.rip...@free-electrons.com>
> ---
> drivers/dma/dw/core.c | 92
> +++++++++++++++++++++++++++------------------------
> 1 file changed, 49 insertions(+), 43 deletions(-)
>
> diff --git a/drivers/dma/dw/core.c b/drivers/dma/dw/core.c
> index 1af731b83b3f..a3d3a51387c6 100644
> --- a/drivers/dma/dw/core.c
> +++ b/drivers/dma/dw/core.c
> @@ -955,8 +955,7 @@ static inline void convert_burst(u32 *maxburst)
> *maxburst = 0;
> }
>
> -static int
> -set_runtime_config(struct dma_chan *chan, struct dma_slave_config *sconfig)
> +static int dwc_config(struct dma_chan *chan, struct dma_slave_config
> *sconfig)
> {
> struct dw_dma_chan *dwc = to_dw_dma_chan(chan);
>
> @@ -977,29 +976,54 @@ set_runtime_config(struct dma_chan *chan, struct
> dma_slave_config *sconfig)
> return 0;
> }
>
> -static inline void dwc_chan_pause(struct dw_dma_chan *dwc)
> +static inline void dwc_chan_resume(struct dw_dma_chan *dwc)
Could we keep the order of functions as previous?
> {
> u32 cfglo = channel_readl(dwc, CFG_LO);
> - unsigned int count = 20; /* timeout iterations */
>
> + channel_writel(dwc, CFG_LO, cfglo & ~DWC_CFGL_CH_SUSP);
> +
> + dwc->paused = false;
> +}
> +
> +static int dwc_pause(struct dma_chan *chan)
> +{
> + struct dw_dma_chan *dwc = to_dw_dma_chan(chan);
> + unsigned long flags;
> + unsigned int count = 20; /* timeout iterations */
> + u32 cfglo;
> +
> + spin_lock_irqsave(&dwc->lock, flags);
> +
> + cfglo = channel_readl(dwc, CFG_LO);
> channel_writel(dwc, CFG_LO, cfglo | DWC_CFGL_CH_SUSP);
> while (!(channel_readl(dwc, CFG_LO) & DWC_CFGL_FIFO_EMPTY) && count--)
> udelay(2);
>
> dwc->paused = true;
> +
> + spin_unlock_irqrestore(&dwc->lock, flags);
> +
> + return 0;
> }
>
> -static inline void dwc_chan_resume(struct dw_dma_chan *dwc)
> +static int dwc_resume(struct dma_chan *chan)
> {
> - u32 cfglo = channel_readl(dwc, CFG_LO);
> + struct dw_dma_chan *dwc = to_dw_dma_chan(chan);
> + unsigned long flags;
>
> - channel_writel(dwc, CFG_LO, cfglo & ~DWC_CFGL_CH_SUSP);
> + if (!dwc->paused)
> + return 0;
>
> - dwc->paused = false;
> + spin_lock_irqsave(&dwc->lock, flags);
> +
> + dwc_chan_resume(dwc);
> +
> + spin_unlock_irqrestore(&dwc->lock, flags);
> +
> + return 0;
> }
>
> -static int dwc_control(struct dma_chan *chan, enum dma_ctrl_cmd cmd,
> - unsigned long arg)
> +static int dwc_terminate_all(struct dma_chan *chan)
> {
> struct dw_dma_chan *dwc = to_dw_dma_chan(chan);
> struct dw_dma *dw = to_dw_dma(chan->device);
> @@ -1007,44 +1031,23 @@ static int dwc_control(struct dma_chan *chan, enum
> dma_ctrl_cmd cmd,
> unsigned long flags;
> LIST_HEAD(list);
>
> - if (cmd == DMA_PAUSE) {
> - spin_lock_irqsave(&dwc->lock, flags);
> -
> - dwc_chan_pause(dwc);
> -
> - spin_unlock_irqrestore(&dwc->lock, flags);
> - } else if (cmd == DMA_RESUME) {
> - if (!dwc->paused)
> - return 0;
> -
> - spin_lock_irqsave(&dwc->lock, flags);
> -
> - dwc_chan_resume(dwc);
> -
> - spin_unlock_irqrestore(&dwc->lock, flags);
> - } else if (cmd == DMA_TERMINATE_ALL) {
> - spin_lock_irqsave(&dwc->lock, flags);
> + spin_lock_irqsave(&dwc->lock, flags);
>
> - clear_bit(DW_DMA_IS_SOFT_LLP, &dwc->flags);
> + clear_bit(DW_DMA_IS_SOFT_LLP, &dwc->flags);
>
> - dwc_chan_disable(dw, dwc);
> + dwc_chan_disable(dw, dwc);
>
> - dwc_chan_resume(dwc);
> + dwc_chan_resume(dwc);
>
> - /* active_list entries will end up before queued entries */
> - list_splice_init(&dwc->queue, &list);
> - list_splice_init(&dwc->active_list, &list);
> + /* active_list entries will end up before queued entries */
> + list_splice_init(&dwc->queue, &list);
> + list_splice_init(&dwc->active_list, &list);
>
> - spin_unlock_irqrestore(&dwc->lock, flags);
> + spin_unlock_irqrestore(&dwc->lock, flags);
>
> - /* Flush all pending and queued descriptors */
> - list_for_each_entry_safe(desc, _desc, &list, desc_node)
> - dwc_descriptor_complete(dwc, desc, false);
> - } else if (cmd == DMA_SLAVE_CONFIG) {
> - return set_runtime_config(chan, (struct dma_slave_config *)arg);
> - } else {
> - return -ENXIO;
> - }
> + /* Flush all pending and queued descriptors */
> + list_for_each_entry_safe(desc, _desc, &list, desc_node)
> + dwc_descriptor_complete(dwc, desc, false);
>
> return 0;
> }
> @@ -1654,7 +1657,10 @@ int dw_dma_probe(struct dw_dma_chip *chip, struct
> dw_dma_platform_data *pdata)
> dw->dma.device_prep_dma_memcpy = dwc_prep_dma_memcpy;
>
> dw->dma.device_prep_slave_sg = dwc_prep_slave_sg;
> - dw->dma.device_control = dwc_control;
> + dw->dma.device_config = dwc_config;
> + dw->dma.device_pause = dwc_pause;
> + dw->dma.device_resume = dwc_resume;
> + dw->dma.device_terminate_all = dwc_terminate_all;
>
> dw->dma.device_tx_status = dwc_tx_status;
> dw->dma.device_issue_pending = dwc_issue_pending;
--
Andy Shevchenko <andriy.shevche...@intel.com>
Intel Finland Oy
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