[linux-yocto] [PATCH 2/6] dmaengine: dw: apply both HS interfaces and remove slave_id usage

wan.ahmad.zainie.wan.mohamad at intel.com wan.ahmad.zainie.wan.mohamad at intel.com
Mon Nov 16 18:54:15 PST 2015


From: Andy Shevchenko <andriy.shevchenko at linux.intel.com>

Instead of one request line member let's use both source and destination ones.
Usually we have no such hardware except Atmel MMC controller found on AVR32
platform (see arch/avr32/mach-at32ap/at32ap700x.c and
drivers/mmc/host/atmel-mci.c).

This patch removes slave_id usage since it'll be removed from the generic
structure in later. This breaks the non-ACPI / non-DT cases for the users of
the driver, i.e. SPI and HSUART. However, these cases mean only PCI enumerated
devices for now, which is anyway broken (considering more than one DMA
controller in the system) and this patch series is intended to fix that
eventually.

The ACPI and DT cases shall be aware of the channel direction when setting
request lines, but this is a minor problem that would be addressed in future.

Suggested-by: Arnd Bergmann <arnd at arndb.de>
Signed-off-by: Andy Shevchenko <andriy.shevchenko at linux.intel.com>
Signed-off-by: Vinod Koul <vinod.koul at intel.com>
(cherry picked from commit 8950052029874a6738552debb45077c596e90e6b)

Signed-off-by: Maurice Petallo <mauricex.r.petallo at intel.com>
Change-Id: I611f2804bd956a32c718e730a5eccac4018448cc
Reviewed-on: https://git-gar-1.devtools.intel.com/gerrit/4362
Reviewed-by: Wan Mohamad, Wan Ahmad Zainie <wan.ahmad.zainie.wan.mohamad at intel.com>
---
 drivers/dma/dw/core.c     | 32 ++------------------------------
 drivers/dma/dw/platform.c |  6 ++++--
 drivers/dma/dw/regs.h     |  7 ++++---
 3 files changed, 10 insertions(+), 35 deletions(-)

diff --git a/drivers/dma/dw/core.c b/drivers/dma/dw/core.c
index 1030070..2896d16 100644
--- a/drivers/dma/dw/core.c
+++ b/drivers/dma/dw/core.c
@@ -37,24 +37,6 @@
  * which does not support descriptor writeback.
  */
 
-static inline bool is_request_line_unset(struct dw_dma_chan *dwc)
-{
-	return dwc->request_line == (typeof(dwc->request_line))~0;
-}
-
-static inline void dwc_set_masters(struct dw_dma_chan *dwc)
-{
-	struct dw_dma *dw = to_dw_dma(dwc->chan.device);
-	struct dw_dma_slave *dws = dwc->chan.private;
-	unsigned char mmax = dw->nr_masters - 1;
-
-	if (!is_request_line_unset(dwc))
-		return;
-
-	dwc->src_master = min_t(unsigned char, mmax, dwc_get_sms(dws));
-	dwc->dst_master = min_t(unsigned char, mmax, dwc_get_dms(dws));
-}
-
 #define DWC_DEFAULT_CTLLO(_chan) ({				\
 		struct dw_dma_chan *_dwc = to_dw_dma_chan(_chan);	\
 		struct dma_slave_config	*_sconfig = &_dwc->dma_sconfig;	\
@@ -162,10 +144,8 @@ static void dwc_initialize(struct dw_dma_chan *dwc)
 		cfghi |= DWC_CFGH_DST_PER(dws->dst_id);
 		cfghi |= DWC_CFGH_SRC_PER(dws->src_id);
 	} else {
-		if (dwc->direction == DMA_MEM_TO_DEV)
-			cfghi = DWC_CFGH_DST_PER(dwc->request_line);
-		else if (dwc->direction == DMA_DEV_TO_MEM)
-			cfghi = DWC_CFGH_SRC_PER(dwc->request_line);
+		cfghi |= DWC_CFGH_DST_PER(dwc->dst_id);
+		cfghi |= DWC_CFGH_SRC_PER(dwc->src_id);
 	}
 
 	channel_writel(dwc, CFG_LO, cfglo);
@@ -987,10 +967,6 @@ set_runtime_config(struct dma_chan *chan, struct dma_slave_config *sconfig)
 	memcpy(&dwc->dma_sconfig, sconfig, sizeof(*sconfig));
 	dwc->direction = sconfig->direction;
 
-	/* Take the request line from slave_id member */
-	if (is_request_line_unset(dwc))
-		dwc->request_line = sconfig->slave_id;
-
 	convert_burst(&dwc->dma_sconfig.src_maxburst);
 	convert_burst(&dwc->dma_sconfig.dst_maxburst);
 
@@ -1143,8 +1119,6 @@ static int dwc_alloc_chan_resources(struct dma_chan *chan)
 	 * doesn't mean what you think it means), and status writeback.
 	 */
 
-	dwc_set_masters(dwc);
-
 	spin_lock_irqsave(&dwc->lock, flags);
 	i = dwc->descs_allocated;
 	while (dwc->descs_allocated < NR_DESCS_PER_CHANNEL) {
@@ -1202,7 +1176,6 @@ static void dwc_free_chan_resources(struct dma_chan *chan)
 	list_splice_init(&dwc->free_list, &list);
 	dwc->descs_allocated = 0;
 	dwc->initialized = false;
-	dwc->request_line = ~0;
 
 	/* Disable interrupts */
 	channel_clear_bit(dw, MASK.XFER, dwc->mask);
@@ -1612,7 +1585,6 @@ int dw_dma_probe(struct dw_dma_chip *chip, struct dw_dma_platform_data *pdata)
 		channel_clear_bit(dw, CH_EN, dwc->mask);
 
 		dwc->direction = DMA_TRANS_NONE;
-		dwc->request_line = ~0;
 
 		/* Hardware configuration */
 		if (autocfg) {
diff --git a/drivers/dma/dw/platform.c b/drivers/dma/dw/platform.c
index e35d975..3b71768 100644
--- a/drivers/dma/dw/platform.c
+++ b/drivers/dma/dw/platform.c
@@ -41,7 +41,8 @@ static bool dw_dma_of_filter(struct dma_chan *chan, void *param)
 	if (chan->device != &fargs->dw->dma)
 		return false;
 
-	dwc->request_line = fargs->req;
+	dwc->src_id = fargs->req;
+	dwc->dst_id = fargs->req;
 	dwc->src_master	= fargs->src;
 	dwc->dst_master	= fargs->dst;
 
@@ -86,7 +87,8 @@ static bool dw_dma_acpi_filter(struct dma_chan *chan, void *param)
 	    chan->chan_id != dma_spec->chan_id)
 		return false;
 
-	dwc->request_line = dma_spec->slave_id;
+	dwc->src_id = dma_spec->slave_id;
+	dwc->dst_id = dma_spec->slave_id;
 	dwc->src_master = dwc_get_sms(NULL);
 	dwc->dst_master = dwc_get_dms(NULL);
 
diff --git a/drivers/dma/dw/regs.h b/drivers/dma/dw/regs.h
index f6c2caf..73df90d 100644
--- a/drivers/dma/dw/regs.h
+++ b/drivers/dma/dw/regs.h
@@ -221,9 +221,10 @@ struct dw_dma_chan {
 	bool			nollp;
 
 	/* custom slave configuration */
-	unsigned int		request_line;
-	unsigned char		src_master;
-	unsigned char		dst_master;
+	u8			src_id;
+	u8			dst_id;
+	u8			src_master;
+	u8			dst_master;
 
 	/* configuration passed via DMA_SLAVE_CONFIG */
 	struct dma_slave_config dma_sconfig;
-- 
1.9.1



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