[PATCH v2 0/6] ARM: at91: move to generic DMA device tree binding

[PATCH v2 0/6] ARM: at91: move to generic DMA device tree binding

[ludovic.desroches]

From: Ludovic Desroches <ludovic.desroches@atmel.com>

Hi,

This set of patches introduces DMA device tree bindings support for the atmel
DMA controller and first driver conversions.

Patch 3/6 has already been taken by Wolfram.

v2 changes:
- update documentation about dma bindings according to Nicolas' comments
- put dtsi changes in a separate patch
- add dtb update for i2c and mci nodes

Ludovic Desroches (6):
  at_hdmac: move to generic DMA binding
  ARM: at91: dts: set #dma-cells to the correct value
  i2c: at91: convert to dma_request_slave_channel_compat()
  ARM: at91: dts: add i2c dma support
  mci: at91: convert to dma_request_slave_channel_compat()
  ARM: at91: dts: add MCI DMA support

 .../devicetree/bindings/dma/atmel-dma.txt          | 35 ++++++--
 arch/arm/boot/dts/at91sam9g45.dtsi                 |  5 ++
 arch/arm/boot/dts/at91sam9n12.dtsi                 |  9 +++
 arch/arm/boot/dts/at91sam9x5.dtsi                  | 15 ++++
 arch/arm/boot/dts/sama5d3.dtsi                     | 19 ++++-
 drivers/dma/at_hdmac.c                             | 93 ++++++++++++++++++++--
 drivers/dma/at_hdmac_regs.h                        |  4 +
 drivers/i2c/busses/i2c-at91.c                      | 49 ++++++------
 drivers/mmc/host/atmel-mci.c                       | 25 +++---
 9 files changed, 204 insertions(+), 50 deletions(-)

-- 
1.7.11.3

[PATCH 1/6] at_hdmac: move to generic DMA binding

[ludovic.desroches-AIFe0yeh4nAAvxtiuMwx3w]

From: Ludovic Desroches <ludovic.desroches-AIFe0yeh4nAAvxtiuMwx3w@public.gmane.org>

Update at_hdmac driver to support generic DMA device tree binding. Devices
can still request channel with dma_request_channel() then it doesn't break
DMA for non DT boards.

Signed-off-by: Ludovic Desroches <ludovic.desroches-AIFe0yeh4nAAvxtiuMwx3w@public.gmane.org>
Acked-by: Nicolas Ferre <nicolas.ferre-AIFe0yeh4nAAvxtiuMwx3w@public.gmane.org>
Acked-by: Jean-Christophe PLAGNIOL-VILLARD <plagnioj-sclMFOaUSTBWk0Htik3J/w@public.gmane.org>
---
 .../devicetree/bindings/dma/atmel-dma.txt          | 35 ++++++--
 drivers/dma/at_hdmac.c                             | 93 ++++++++++++++++++++--
 drivers/dma/at_hdmac_regs.h                        |  4 +
 3 files changed, 121 insertions(+), 11 deletions(-)

diff --git a/Documentation/devicetree/bindings/dma/atmel-dma.txt b/Documentation/devicetree/bindings/dma/atmel-dma.txt
index 3c046ee..c80e8a3 100644
--- a/Documentation/devicetree/bindings/dma/atmel-dma.txt
+++ b/Documentation/devicetree/bindings/dma/atmel-dma.txt
@@ -1,14 +1,39 @@
 * Atmel Direct Memory Access Controller (DMA)
 
 Required properties:
-- compatible: Should be "atmel,<chip>-dma"
-- reg: Should contain DMA registers location and length
-- interrupts: Should contain DMA interrupt
+- compatible: Should be "atmel,<chip>-dma".
+- reg: Should contain DMA registers location and length.
+- interrupts: Should contain DMA interrupt.
+- #dma-cells: Must be <2>, used to represent the number of integer cells in
+the dmas property of client devices.
 
-Examples:
+Example:
 
-dma@ffffec00 {
+dma0: dma@ffffec00 {
 	compatible = "atmel,at91sam9g45-dma";
 	reg = <0xffffec00 0x200>;
 	interrupts = <21>;
+	#dma-cells = <2>;
+};
+
+DMA clients connected to the Atmel DMA controller must use the format
+described in the dma.txt file, using a three-cell specifier for each channel:
+a phandle plus two interger cells.
+The three cells in order are:
+
+1. A phandle pointing to the DMA controller.
+2. The memory interface (16 most significant bits), the peripheral interface
+(16 less significant bits).
+3. The peripheral identifier for the hardware handshaking interface. The
+identifier can be different for tx and rx.
+
+Example:
+
+i2c0@i2c@f8010000 {
+	compatible = "atmel,at91sam9x5-i2c";
+	reg = <0xf8010000 0x100>;
+	interrupts = <9 4 6>;
+	dmas = <&dma0 1 7>,
+	       <&dma0 1 8>;
+	dma-names = "tx", "rx";
 };
diff --git a/drivers/dma/at_hdmac.c b/drivers/dma/at_hdmac.c
index de4e930..2a63dbe 100644
--- a/drivers/dma/at_hdmac.c
+++ b/drivers/dma/at_hdmac.c
@@ -24,6 +24,7 @@
 #include <linux/slab.h>
 #include <linux/of.h>
 #include <linux/of_device.h>
+#include <linux/of_dma.h>
 
 #include "at_hdmac_regs.h"
 #include "dmaengine.h"
@@ -677,7 +678,7 @@ atc_prep_slave_sg(struct dma_chan *chan, struct scatterlist *sgl,
 		ctrlb |=  ATC_DST_ADDR_MODE_FIXED
 			| ATC_SRC_ADDR_MODE_INCR
 			| ATC_FC_MEM2PER
-			| ATC_SIF(AT_DMA_MEM_IF) | ATC_DIF(AT_DMA_PER_IF);
+			| ATC_SIF(atchan->mem_if) | ATC_DIF(atchan->per_if);
 		reg = sconfig->dst_addr;
 		for_each_sg(sgl, sg, sg_len, i) {
 			struct at_desc	*desc;
@@ -716,7 +717,7 @@ atc_prep_slave_sg(struct dma_chan *chan, struct scatterlist *sgl,
 		ctrlb |=  ATC_DST_ADDR_MODE_INCR
 			| ATC_SRC_ADDR_MODE_FIXED
 			| ATC_FC_PER2MEM
-			| ATC_SIF(AT_DMA_PER_IF) | ATC_DIF(AT_DMA_MEM_IF);
+			| ATC_SIF(atchan->per_if) | ATC_DIF(atchan->mem_if);
 
 		reg = sconfig->src_addr;
 		for_each_sg(sgl, sg, sg_len, i) {
@@ -822,8 +823,8 @@ atc_dma_cyclic_fill_desc(struct dma_chan *chan, struct at_desc *desc,
 		desc->lli.ctrlb = ATC_DST_ADDR_MODE_FIXED
 				| ATC_SRC_ADDR_MODE_INCR
 				| ATC_FC_MEM2PER
-				| ATC_SIF(AT_DMA_MEM_IF)
-				| ATC_DIF(AT_DMA_PER_IF);
+				| ATC_SIF(atchan->mem_if)
+				| ATC_DIF(atchan->per_if);
 		break;
 
 	case DMA_DEV_TO_MEM:
@@ -833,8 +834,8 @@ atc_dma_cyclic_fill_desc(struct dma_chan *chan, struct at_desc *desc,
 		desc->lli.ctrlb = ATC_DST_ADDR_MODE_INCR
 				| ATC_SRC_ADDR_MODE_FIXED
 				| ATC_FC_PER2MEM
-				| ATC_SIF(AT_DMA_PER_IF)
-				| ATC_DIF(AT_DMA_MEM_IF);
+				| ATC_SIF(atchan->per_if)
+				| ATC_DIF(atchan->mem_if);
 		break;
 
 	default:
@@ -1190,6 +1191,67 @@ static void atc_free_chan_resources(struct dma_chan *chan)
 	dev_vdbg(chan2dev(chan), "free_chan_resources: done\n");
 }
 
+static bool at_dma_filter(struct dma_chan *chan, void *slave)
+{
+	struct at_dma_slave *atslave = slave;
+
+	if (atslave->dma_dev == chan->device->dev) {
+		chan->private = atslave;
+		return true;
+	} else {
+		return false;
+	}
+}
+
+#ifdef CONFIG_OF
+static struct dma_chan *at_dma_xlate(struct of_phandle_args *dma_spec,
+				     struct of_dma *of_dma)
+{
+	struct dma_chan *chan;
+	struct at_dma_chan *atchan;
+	struct at_dma_slave *atslave;
+	dma_cap_mask_t mask;
+	unsigned int per_id;
+	struct platform_device *dmac_pdev;
+
+	if (dma_spec->args_count != 2)
+		return NULL;
+
+	dmac_pdev = of_find_device_by_node(dma_spec->np);
+
+	dma_cap_zero(mask);
+	dma_cap_set(DMA_SLAVE, mask);
+
+	atslave = devm_kzalloc(&dmac_pdev->dev, sizeof(*atslave), GFP_KERNEL);
+	if (!atslave)
+		return NULL;
+	/*
+	 * We can fill both SRC_PER and DST_PER, one of these fields will be
+	 * ignored depending on DMA transfer direction.
+	 */
+	per_id = dma_spec->args[1];
+	atslave->cfg = ATC_FIFOCFG_HALFFIFO | ATC_DST_H2SEL_HW
+		      | ATC_SRC_H2SEL_HW | ATC_DST_PER(per_id)
+		      | ATC_SRC_PER(per_id);
+	atslave->dma_dev = &dmac_pdev->dev;
+
+	chan = dma_request_channel(mask, at_dma_filter, atslave);
+	if (!chan)
+		return NULL;
+
+	atchan = to_at_dma_chan(chan);
+	atchan->per_if = dma_spec->args[0] & 0xff;
+	atchan->mem_if = (dma_spec->args[0] >> 16) & 0xff;
+
+	return chan;
+}
+#else
+static struct dma_chan *at_dma_xlate(struct of_phandle_args *dma_spec,
+				     struct of_dma *of_dma)
+{
+	return NULL;
+}
+#endif
 
 /*--  Module Management  -----------------------------------------------*/
 
@@ -1344,6 +1406,8 @@ static int __init at_dma_probe(struct platform_device *pdev)
 	for (i = 0; i < plat_dat->nr_channels; i++) {
 		struct at_dma_chan	*atchan = &atdma->chan[i];
 
+		atchan->mem_if = AT_DMA_MEM_IF;
+		atchan->per_if = AT_DMA_PER_IF;
 		atchan->chan_common.device = &atdma->dma_common;
 		dma_cookie_init(&atchan->chan_common);
 		list_add_tail(&atchan->chan_common.device_node,
@@ -1390,8 +1454,25 @@ static int __init at_dma_probe(struct platform_device *pdev)
 
 	dma_async_device_register(&atdma->dma_common);
 
+	/*
+	 * Do not return an error if the dmac node is not present in order to
+	 * not break the existing way of requesting channel with
+	 * dma_request_channel().
+	 */
+	if (pdev->dev.of_node) {
+		err = of_dma_controller_register(pdev->dev.of_node,
+						 at_dma_xlate, atdma);
+		if (err) {
+			dev_err(&pdev->dev, "could not register of_dma_controller\n");
+			goto err_of_dma_controller_register;
+		}
+	}
+
 	return 0;
 
+err_of_dma_controller_register:
+	dma_async_device_unregister(&atdma->dma_common);
+	dma_pool_destroy(atdma->dma_desc_pool);
 err_pool_create:
 	platform_set_drvdata(pdev, NULL);
 	free_irq(platform_get_irq(pdev, 0), atdma);
diff --git a/drivers/dma/at_hdmac_regs.h b/drivers/dma/at_hdmac_regs.h
index 0eb3c13..c604d26 100644
--- a/drivers/dma/at_hdmac_regs.h
+++ b/drivers/dma/at_hdmac_regs.h
@@ -220,6 +220,8 @@ enum atc_status {
  * @device: parent device
  * @ch_regs: memory mapped register base
  * @mask: channel index in a mask
+ * @per_if: peripheral interface
+ * @mem_if: memory interface
  * @status: transmit status information from irq/prep* functions
  *                to tasklet (use atomic operations)
  * @tasklet: bottom half to finish transaction work
@@ -238,6 +240,8 @@ struct at_dma_chan {
 	struct at_dma		*device;
 	void __iomem		*ch_regs;
 	u8			mask;
+	u8			per_if;
+	u8			mem_if;
 	unsigned long		status;
 	struct tasklet_struct	tasklet;
 	u32			save_cfg;
-- 
1.7.11.3

[PATCH 2/6] ARM: at91: dts: set #dma-cells to the correct value

[ludovic.desroches-AIFe0yeh4nAAvxtiuMwx3w]

From: Ludovic Desroches <ludovic.desroches-AIFe0yeh4nAAvxtiuMwx3w@public.gmane.org>

Moving to generic DMA DT binding involves to set #dma-cells to 2.

Signed-off-by: Ludovic Desroches <ludovic.desroches-AIFe0yeh4nAAvxtiuMwx3w@public.gmane.org>
---
 arch/arm/boot/dts/at91sam9g45.dtsi | 1 +
 arch/arm/boot/dts/at91sam9n12.dtsi | 1 +
 arch/arm/boot/dts/at91sam9x5.dtsi  | 2 ++
 arch/arm/boot/dts/sama5d3.dtsi     | 4 ++--
 4 files changed, 6 insertions(+), 2 deletions(-)

diff --git a/arch/arm/boot/dts/at91sam9g45.dtsi b/arch/arm/boot/dts/at91sam9g45.dtsi
index 6b1d4ca..275e768 100644
--- a/arch/arm/boot/dts/at91sam9g45.dtsi
+++ b/arch/arm/boot/dts/at91sam9g45.dtsi
@@ -108,6 +108,7 @@
 				compatible = "atmel,at91sam9g45-dma";
 				reg = <0xffffec00 0x200>;
 				interrupts = <21 4 0>;
+				#dma-cells = <2>;
 			};
 
 			pinctrl@fffff200 {
diff --git a/arch/arm/boot/dts/at91sam9n12.dtsi b/arch/arm/boot/dts/at91sam9n12.dtsi
index 7750f98..acc4526 100644
--- a/arch/arm/boot/dts/at91sam9n12.dtsi
+++ b/arch/arm/boot/dts/at91sam9n12.dtsi
@@ -110,6 +110,7 @@
 				compatible = "atmel,at91sam9g45-dma";
 				reg = <0xffffec00 0x200>;
 				interrupts = <20 4 0>;
+				#dma-cells = <2>;
 			};
 
 			pinctrl@fffff400 {
diff --git a/arch/arm/boot/dts/at91sam9x5.dtsi b/arch/arm/boot/dts/at91sam9x5.dtsi
index 3870322..8e83d87 100644
--- a/arch/arm/boot/dts/at91sam9x5.dtsi
+++ b/arch/arm/boot/dts/at91sam9x5.dtsi
@@ -104,12 +104,14 @@
 				compatible = "atmel,at91sam9g45-dma";
 				reg = <0xffffec00 0x200>;
 				interrupts = <20 4 0>;
+				#dma-cells = <2>;
 			};
 
 			dma1: dma-controller@ffffee00 {
 				compatible = "atmel,at91sam9g45-dma";
 				reg = <0xffffee00 0x200>;
 				interrupts = <21 4 0>;
+				#dma-cells = <2>;
 			};
 
 			pinctrl@fffff400 {
diff --git a/arch/arm/boot/dts/sama5d3.dtsi b/arch/arm/boot/dts/sama5d3.dtsi
index 39b0458..95c00a3 100644
--- a/arch/arm/boot/dts/sama5d3.dtsi
+++ b/arch/arm/boot/dts/sama5d3.dtsi
@@ -348,14 +348,14 @@
 				compatible = "atmel,at91sam9g45-dma";
 				reg = <0xffffe600 0x200>;
 				interrupts = <30 4 0>;
-				#dma-cells = <1>;
+				#dma-cells = <2>;
 			};
 
 			dma1: dma-controller@ffffe800 {
 				compatible = "atmel,at91sam9g45-dma";
 				reg = <0xffffe800 0x200>;
 				interrupts = <31 4 0>;
-				#dma-cells = <1>;
+				#dma-cells = <2>;
 			};
 
 			ramc0: ramc@ffffea00 {
-- 
1.7.11.3

[PATCH 3/6] i2c: at91: convert to dma_request_slave_channel_compat()

[ludovic.desroches-AIFe0yeh4nAAvxtiuMwx3w]

From: Ludovic Desroches <ludovic.desroches-AIFe0yeh4nAAvxtiuMwx3w@public.gmane.org>

Use generic DMA DT helper. Platforms booting with or without DT populated are
both supported.

Signed-off-by: Ludovic Desroches <ludovic.desroches-AIFe0yeh4nAAvxtiuMwx3w@public.gmane.org>
---
 drivers/i2c/busses/i2c-at91.c | 49 ++++++++++++++++++++++---------------------
 1 file changed, 25 insertions(+), 24 deletions(-)

diff --git a/drivers/i2c/busses/i2c-at91.c b/drivers/i2c/busses/i2c-at91.c
index 75195e3..7ffd544 100644
--- a/drivers/i2c/busses/i2c-at91.c
+++ b/drivers/i2c/busses/i2c-at91.c
@@ -607,11 +607,16 @@ MODULE_DEVICE_TABLE(of, atmel_twi_dt_ids);
 #define atmel_twi_dt_ids NULL
 #endif
 
-static bool filter(struct dma_chan *chan, void *slave)
+static bool filter(struct dma_chan *chan, void *pdata)
 {
-	struct at_dma_slave *sl = slave;
+	struct at91_twi_pdata *sl_pdata = pdata;
+	struct at_dma_slave *sl;
 
-	if (sl->dma_dev == chan->device->dev) {
+	if (!sl_pdata)
+		return false;
+
+	sl = &sl_pdata->dma_slave;
+	if (sl && (sl->dma_dev == chan->device->dev)) {
 		chan->private = sl;
 		return true;
 	} else {
@@ -622,11 +627,10 @@ static bool filter(struct dma_chan *chan, void *slave)
 static int at91_twi_configure_dma(struct at91_twi_dev *dev, u32 phy_addr)
 {
 	int ret = 0;
-	struct at_dma_slave *sdata;
+	struct at91_twi_pdata *pdata = dev->pdata;
 	struct dma_slave_config slave_config;
 	struct at91_twi_dma *dma = &dev->dma;
-
-	sdata = &dev->pdata->dma_slave;
+	dma_cap_mask_t mask;
 
 	memset(&slave_config, 0, sizeof(slave_config));
 	slave_config.src_addr = (dma_addr_t)phy_addr + AT91_TWI_RHR;
@@ -637,25 +641,22 @@ static int at91_twi_configure_dma(struct at91_twi_dev *dev, u32 phy_addr)
 	slave_config.dst_maxburst = 1;
 	slave_config.device_fc = false;
 
-	if (sdata && sdata->dma_dev) {
-		dma_cap_mask_t mask;
+	dma_cap_zero(mask);
+	dma_cap_set(DMA_SLAVE, mask);
 
-		dma_cap_zero(mask);
-		dma_cap_set(DMA_SLAVE, mask);
-		dma->chan_tx = dma_request_channel(mask, filter, sdata);
-		if (!dma->chan_tx) {
-			dev_err(dev->dev, "no DMA channel available for tx\n");
-			ret = -EBUSY;
-			goto error;
-		}
-		dma->chan_rx = dma_request_channel(mask, filter, sdata);
-		if (!dma->chan_rx) {
-			dev_err(dev->dev, "no DMA channel available for rx\n");
-			ret = -EBUSY;
-			goto error;
-		}
-	} else {
-		ret = -EINVAL;
+	dma->chan_tx = dma_request_slave_channel_compat(mask, filter, pdata,
+							dev->dev, "tx");
+	if (!dma->chan_tx) {
+		dev_err(dev->dev, "can't get a DMA channel for tx\n");
+		ret = -EBUSY;
+		goto error;
+	}
+
+	dma->chan_rx = dma_request_slave_channel_compat(mask, filter, pdata,
+							dev->dev, "rx");
+	if (!dma->chan_rx) {
+		dev_err(dev->dev, "can't get a DMA channel for rx\n");
+		ret = -EBUSY;
 		goto error;
 	}
 
-- 
1.7.11.3

[PATCH 4/6] ARM: at91: dts: add i2c dma support

[ludovic.desroches]

From: Ludovic Desroches <ludovic.desroches@atmel.com>

Add DMA resources to i2c nodes.

Signed-off-by: Ludovic Desroches <ludovic.desroches@atmel.com>
---
 arch/arm/boot/dts/at91sam9n12.dtsi | 6 ++++++
 arch/arm/boot/dts/at91sam9x5.dtsi  | 9 +++++++++
 arch/arm/boot/dts/sama5d3.dtsi     | 9 +++++++++
 3 files changed, 24 insertions(+)

diff --git a/arch/arm/boot/dts/at91sam9n12.dtsi b/arch/arm/boot/dts/at91sam9n12.dtsi
index acc4526..f912124 100644
--- a/arch/arm/boot/dts/at91sam9n12.dtsi
+++ b/arch/arm/boot/dts/at91sam9n12.dtsi
@@ -361,6 +361,9 @@
 				compatible = "atmel,at91sam9x5-i2c";
 				reg = <0xf8010000 0x100>;
 				interrupts = <9 4 6>;
+				dmas = <&dma0 1 13>,
+				       <&dma0 1 14>;
+				dma-names = "tx", "rx";
 				#address-cells = <1>;
 				#size-cells = <0>;
 				status = "disabled";
@@ -370,6 +373,9 @@
 				compatible = "atmel,at91sam9x5-i2c";
 				reg = <0xf8014000 0x100>;
 				interrupts = <10 4 6>;
+				dmas = <&dma0 1 15>,
+				       <&dma0 1 16>;
+				dma-names = "tx", "rx";
 				#address-cells = <1>;
 				#size-cells = <0>;
 				status = "disabled";
diff --git a/arch/arm/boot/dts/at91sam9x5.dtsi b/arch/arm/boot/dts/at91sam9x5.dtsi
index 8e83d87..16c9b81 100644
--- a/arch/arm/boot/dts/at91sam9x5.dtsi
+++ b/arch/arm/boot/dts/at91sam9x5.dtsi
@@ -519,6 +519,9 @@
 				compatible = "atmel,at91sam9x5-i2c";
 				reg = <0xf8010000 0x100>;
 				interrupts = <9 4 6>;
+				dmas = <&dma0 1 7>,
+				       <&dma0 1 8>;
+				dma-names = "tx", "rx";
 				#address-cells = <1>;
 				#size-cells = <0>;
 				pinctrl-names = "default";
@@ -530,6 +533,9 @@
 				compatible = "atmel,at91sam9x5-i2c";
 				reg = <0xf8014000 0x100>;
 				interrupts = <10 4 6>;
+				dmas = <&dma1 1 5>,
+				       <&dma1 1 6>;
+				dma-names = "tx", "rx";
 				#address-cells = <1>;
 				#size-cells = <0>;
 				pinctrl-names = "default";
@@ -541,6 +547,9 @@
 				compatible = "atmel,at91sam9x5-i2c";
 				reg = <0xf8018000 0x100>;
 				interrupts = <11 4 6>;
+				dmas = <&dma0 1 9>,
+				       <&dma0 1 10>;
+				dma-names = "tx", "rx";
 				#address-cells = <1>;
 				#size-cells = <0>;
 				pinctrl-names = "default";
diff --git a/arch/arm/boot/dts/sama5d3.dtsi b/arch/arm/boot/dts/sama5d3.dtsi
index 95c00a3..8e87277 100644
--- a/arch/arm/boot/dts/sama5d3.dtsi
+++ b/arch/arm/boot/dts/sama5d3.dtsi
@@ -111,6 +111,9 @@
 				compatible = "atmel,at91sam9x5-i2c";
 				reg = <0xf0014000 0x4000>;
 				interrupts = <18 4 6>;
+				dmas = <&dma0 2 7>,
+				       <&dma0 2 8>;
+				dma-names = "tx", "rx";
 				pinctrl-names = "default";
 				pinctrl-0 = <&pinctrl_i2c0>;
 				#address-cells = <1>;
@@ -122,6 +125,9 @@
 				compatible = "atmel,at91sam9x5-i2c";
 				reg = <0xf0018000 0x4000>;
 				interrupts = <19 4 6>;
+				dmas = <&dma0 2 9>,
+				       <&dma0 2 10>;
+				dma-names = "tx", "rx";
 				pinctrl-names = "default";
 				pinctrl-0 = <&pinctrl_i2c1>;
 				#address-cells = <1>;
@@ -294,6 +300,9 @@
 				compatible = "atmel,at91sam9x5-i2c";
 				reg = <0xf801c000 0x4000>;
 				interrupts = <20 4 6>;
+				dmas = <&dma1 2 11>,
+				       <&dma1 2 12>;
+				dma-names = "tx", "rx";
 				#address-cells = <1>;
 				#size-cells = <0>;
 				status = "disabled";
-- 
1.7.11.3

[PATCH 5/6] mci: at91: convert to dma_request_slave_channel_compat()

[ludovic.desroches]

From: Ludovic Desroches <ludovic.desroches@atmel.com>

Use generic DMA DT helper. Platforms booting with or without DT populated are
both supported.

Signed-off-by: Ludovic Desroches <ludovic.desroches@atmel.com>
Acked-by: Jean-Christophe PLAGNIOL-VILLARD <plagnioj@jcrosoft.com>
Acked-by: Nicolas Ferre <nicolas.ferre@atmel.com>
---
 drivers/mmc/host/atmel-mci.c | 25 ++++++++++++-------------
 1 file changed, 12 insertions(+), 13 deletions(-)

diff --git a/drivers/mmc/host/atmel-mci.c b/drivers/mmc/host/atmel-mci.c
index 10f8b73..73d5d24 100644
--- a/drivers/mmc/host/atmel-mci.c
+++ b/drivers/mmc/host/atmel-mci.c
@@ -2224,10 +2224,15 @@ static void __exit atmci_cleanup_slot(struct atmel_mci_slot *slot,
 	mmc_free_host(slot->mmc);
 }
 
-static bool atmci_filter(struct dma_chan *chan, void *slave)
+static bool atmci_filter(struct dma_chan *chan, void *pdata)
 {
-	struct mci_dma_data	*sl = slave;
+	struct mci_platform_data *sl_pdata = pdata;
+	struct mci_dma_data *sl;
 
+	if (!sl_pdata)
+		return false;
+
+	sl = sl_pdata->dma_slave;
 	if (sl && find_slave_dev(sl) == chan->device->dev) {
 		chan->private = slave_data_ptr(sl);
 		return true;
@@ -2239,24 +2244,18 @@ static bool atmci_filter(struct dma_chan *chan, void *slave)
 static bool atmci_configure_dma(struct atmel_mci *host)
 {
 	struct mci_platform_data	*pdata;
+	dma_cap_mask_t mask;
 
 	if (host == NULL)
 		return false;
 
 	pdata = host->pdev->dev.platform_data;
 
-	if (!pdata)
-		return false;
+	dma_cap_zero(mask);
+	dma_cap_set(DMA_SLAVE, mask);
 
-	if (pdata->dma_slave && find_slave_dev(pdata->dma_slave)) {
-		dma_cap_mask_t mask;
-
-		/* Try to grab a DMA channel */
-		dma_cap_zero(mask);
-		dma_cap_set(DMA_SLAVE, mask);
-		host->dma.chan =
-			dma_request_channel(mask, atmci_filter, pdata->dma_slave);
-	}
+	host->dma.chan = dma_request_slave_channel_compat(mask, atmci_filter, pdata,
+						   	  &host->pdev->dev, "rxtx");
 	if (!host->dma.chan) {
 		dev_warn(&host->pdev->dev, "no DMA channel available\n");
 		return false;
-- 
1.7.11.3

[PATCH 6/6] ARM: at91: dts: add MCI DMA support

[ludovic.desroches-AIFe0yeh4nAAvxtiuMwx3w]

From: Ludovic Desroches <ludovic.desroches-AIFe0yeh4nAAvxtiuMwx3w@public.gmane.org>

Add DMA resources to MCI nodes.

Signed-off-by: Ludovic Desroches <ludovic.desroches-AIFe0yeh4nAAvxtiuMwx3w@public.gmane.org>
---
 arch/arm/boot/dts/at91sam9g45.dtsi | 4 ++++
 arch/arm/boot/dts/at91sam9n12.dtsi | 2 ++
 arch/arm/boot/dts/at91sam9x5.dtsi  | 4 ++++
 arch/arm/boot/dts/sama5d3.dtsi     | 6 ++++++
 4 files changed, 16 insertions(+)

diff --git a/arch/arm/boot/dts/at91sam9g45.dtsi b/arch/arm/boot/dts/at91sam9g45.dtsi
index 275e768..de2abc0 100644
--- a/arch/arm/boot/dts/at91sam9g45.dtsi
+++ b/arch/arm/boot/dts/at91sam9g45.dtsi
@@ -513,6 +513,8 @@
 				compatible = "atmel,hsmci";
 				reg = <0xfff80000 0x600>;
 				interrupts = <11 4 0>;
+				dmas = <&dma0 1 0>;
+				dma-names = "rxtx";
 				#address-cells = <1>;
 				#size-cells = <0>;
 				status = "disabled";
@@ -522,6 +524,8 @@
 				compatible = "atmel,hsmci";
 				reg = <0xfffd0000 0x600>;
 				interrupts = <29 4 0>;
+				dmas = <&dma0 1 13>;
+				dma-names = "rxtx";
 				#address-cells = <1>;
 				#size-cells = <0>;
 				status = "disabled";
diff --git a/arch/arm/boot/dts/at91sam9n12.dtsi b/arch/arm/boot/dts/at91sam9n12.dtsi
index f912124..0b61c41 100644
--- a/arch/arm/boot/dts/at91sam9n12.dtsi
+++ b/arch/arm/boot/dts/at91sam9n12.dtsi
@@ -89,6 +89,8 @@
 				compatible = "atmel,hsmci";
 				reg = <0xf0008000 0x600>;
 				interrupts = <12 4 0>;
+				dmas = <&dma0 1 0>
+				dma-names = "rxtx";
 				#address-cells = <1>;
 				#size-cells = <0>;
 				status = "disabled";
diff --git a/arch/arm/boot/dts/at91sam9x5.dtsi b/arch/arm/boot/dts/at91sam9x5.dtsi
index 16c9b81..5f42e7a 100644
--- a/arch/arm/boot/dts/at91sam9x5.dtsi
+++ b/arch/arm/boot/dts/at91sam9x5.dtsi
@@ -449,6 +449,8 @@
 				compatible = "atmel,hsmci";
 				reg = <0xf0008000 0x600>;
 				interrupts = <12 4 0>;
+				dmas = <&dma0 1 0>;
+				dma-names = "rxtx";
 				#address-cells = <1>;
 				#size-cells = <0>;
 				status = "disabled";
@@ -458,6 +460,8 @@
 				compatible = "atmel,hsmci";
 				reg = <0xf000c000 0x600>;
 				interrupts = <26 4 0>;
+				dmas = <&dma1 1 0>;
+				dma-names = "rxtx";
 				#address-cells = <1>;
 				#size-cells = <0>;
 				status = "disabled";
diff --git a/arch/arm/boot/dts/sama5d3.dtsi b/arch/arm/boot/dts/sama5d3.dtsi
index 8e87277..2e643ea 100644
--- a/arch/arm/boot/dts/sama5d3.dtsi
+++ b/arch/arm/boot/dts/sama5d3.dtsi
@@ -60,6 +60,8 @@
 				compatible = "atmel,hsmci";
 				reg = <0xf0000000 0x600>;
 				interrupts = <21 4 0>;
+				dmas = <&dma0 2 0>;
+				dma-names = "rxtx";
 				pinctrl-names = "default";
 				pinctrl-0 = <&pinctrl_mmc0_clk_cmd_dat0 &pinctrl_mmc0_dat1_3 &pinctrl_mmc0_dat4_7>;
 				status = "disabled";
@@ -173,6 +175,8 @@
 				compatible = "atmel,hsmci";
 				reg = <0xf8000000 0x600>;
 				interrupts = <22 4 0>;
+				dmas = <&dma1 2 0>;
+				dma-names = "rxtx";
 				pinctrl-names = "default";
 				pinctrl-0 = <&pinctrl_mmc1_clk_cmd_dat0 &pinctrl_mmc1_dat1_3>;
 				status = "disabled";
@@ -184,6 +188,8 @@
 				compatible = "atmel,hsmci";
 				reg = <0xf8004000 0x600>;
 				interrupts = <23 4 0>;
+				dmas = <&dma1 2 1>;
+				dma-names = "rxtx";
 				pinctrl-names = "default";
 				pinctrl-0 = <&pinctrl_mmc2_clk_cmd_dat0 &pinctrl_mmc2_dat1_3>;
 				status = "disabled";
-- 
1.7.11.3

Re: [PATCH 1/6] at_hdmac: move to generic DMA binding

[Nicolas Ferre]

On 04/16/2013 03:03 PM, ludovic.desroches-AIFe0yeh4nAAvxtiuMwx3w@public.gmane.org :
> From: Ludovic Desroches <ludovic.desroches-AIFe0yeh4nAAvxtiuMwx3w@public.gmane.org>
> 
> Update at_hdmac driver to support generic DMA device tree binding. Devices
> can still request channel with dma_request_channel() then it doesn't break
> DMA for non DT boards.
> 
> Signed-off-by: Ludovic Desroches <ludovic.desroches-AIFe0yeh4nAAvxtiuMwx3w@public.gmane.org>
> Acked-by: Nicolas Ferre <nicolas.ferre-AIFe0yeh4nAAvxtiuMwx3w@public.gmane.org>
> Acked-by: Jean-Christophe PLAGNIOL-VILLARD <plagnioj-sclMFOaUSTBWk0Htik3J/w@public.gmane.org>

I plan to make this whole series go forward for 3.10 because of the
sensitive nature of DMA bindings and the expectations of everybody on
this topic ;-)

Arnd,
Do you feel like giving your "Acked-by" to this patch? I think that you
were pretty in line with Ludovic's RFC, so it may be interesting to have
your support on this...

Vinod,
This series touches several sub-systems, I plan to split it so everyone
can take its corresponding code. Does it seem sensible to send you this
patch alone, extracted from this series, when it is ready?

Thanks, best regards.


> ---
>  .../devicetree/bindings/dma/atmel-dma.txt          | 35 ++++++--
>  drivers/dma/at_hdmac.c                             | 93 ++++++++++++++++++++--
>  drivers/dma/at_hdmac_regs.h                        |  4 +
>  3 files changed, 121 insertions(+), 11 deletions(-)
> 
> diff --git a/Documentation/devicetree/bindings/dma/atmel-dma.txt b/Documentation/devicetree/bindings/dma/atmel-dma.txt
> index 3c046ee..c80e8a3 100644
> --- a/Documentation/devicetree/bindings/dma/atmel-dma.txt
> +++ b/Documentation/devicetree/bindings/dma/atmel-dma.txt
> @@ -1,14 +1,39 @@
>  * Atmel Direct Memory Access Controller (DMA)
>  
>  Required properties:
> -- compatible: Should be "atmel,<chip>-dma"
> -- reg: Should contain DMA registers location and length
> -- interrupts: Should contain DMA interrupt
> +- compatible: Should be "atmel,<chip>-dma".
> +- reg: Should contain DMA registers location and length.
> +- interrupts: Should contain DMA interrupt.
> +- #dma-cells: Must be <2>, used to represent the number of integer cells in
> +the dmas property of client devices.
>  
> -Examples:
> +Example:
>  
> -dma@ffffec00 {
> +dma0: dma@ffffec00 {
>  	compatible = "atmel,at91sam9g45-dma";
>  	reg = <0xffffec00 0x200>;
>  	interrupts = <21>;
> +	#dma-cells = <2>;
> +};
> +
> +DMA clients connected to the Atmel DMA controller must use the format
> +described in the dma.txt file, using a three-cell specifier for each channel:
> +a phandle plus two interger cells.
> +The three cells in order are:
> +
> +1. A phandle pointing to the DMA controller.
> +2. The memory interface (16 most significant bits), the peripheral interface
> +(16 less significant bits).
> +3. The peripheral identifier for the hardware handshaking interface. The
> +identifier can be different for tx and rx.
> +
> +Example:
> +
> +i2c0@i2c@f8010000 {
> +	compatible = "atmel,at91sam9x5-i2c";
> +	reg = <0xf8010000 0x100>;
> +	interrupts = <9 4 6>;
> +	dmas = <&dma0 1 7>,
> +	       <&dma0 1 8>;
> +	dma-names = "tx", "rx";
>  };
> diff --git a/drivers/dma/at_hdmac.c b/drivers/dma/at_hdmac.c
> index de4e930..2a63dbe 100644
> --- a/drivers/dma/at_hdmac.c
> +++ b/drivers/dma/at_hdmac.c
> @@ -24,6 +24,7 @@
>  #include <linux/slab.h>
>  #include <linux/of.h>
>  #include <linux/of_device.h>
> +#include <linux/of_dma.h>
>  
>  #include "at_hdmac_regs.h"
>  #include "dmaengine.h"
> @@ -677,7 +678,7 @@ atc_prep_slave_sg(struct dma_chan *chan, struct scatterlist *sgl,
>  		ctrlb |=  ATC_DST_ADDR_MODE_FIXED
>  			| ATC_SRC_ADDR_MODE_INCR
>  			| ATC_FC_MEM2PER
> -			| ATC_SIF(AT_DMA_MEM_IF) | ATC_DIF(AT_DMA_PER_IF);
> +			| ATC_SIF(atchan->mem_if) | ATC_DIF(atchan->per_if);
>  		reg = sconfig->dst_addr;
>  		for_each_sg(sgl, sg, sg_len, i) {
>  			struct at_desc	*desc;
> @@ -716,7 +717,7 @@ atc_prep_slave_sg(struct dma_chan *chan, struct scatterlist *sgl,
>  		ctrlb |=  ATC_DST_ADDR_MODE_INCR
>  			| ATC_SRC_ADDR_MODE_FIXED
>  			| ATC_FC_PER2MEM
> -			| ATC_SIF(AT_DMA_PER_IF) | ATC_DIF(AT_DMA_MEM_IF);
> +			| ATC_SIF(atchan->per_if) | ATC_DIF(atchan->mem_if);
>  
>  		reg = sconfig->src_addr;
>  		for_each_sg(sgl, sg, sg_len, i) {
> @@ -822,8 +823,8 @@ atc_dma_cyclic_fill_desc(struct dma_chan *chan, struct at_desc *desc,
>  		desc->lli.ctrlb = ATC_DST_ADDR_MODE_FIXED
>  				| ATC_SRC_ADDR_MODE_INCR
>  				| ATC_FC_MEM2PER
> -				| ATC_SIF(AT_DMA_MEM_IF)
> -				| ATC_DIF(AT_DMA_PER_IF);
> +				| ATC_SIF(atchan->mem_if)
> +				| ATC_DIF(atchan->per_if);
>  		break;
>  
>  	case DMA_DEV_TO_MEM:
> @@ -833,8 +834,8 @@ atc_dma_cyclic_fill_desc(struct dma_chan *chan, struct at_desc *desc,
>  		desc->lli.ctrlb = ATC_DST_ADDR_MODE_INCR
>  				| ATC_SRC_ADDR_MODE_FIXED
>  				| ATC_FC_PER2MEM
> -				| ATC_SIF(AT_DMA_PER_IF)
> -				| ATC_DIF(AT_DMA_MEM_IF);
> +				| ATC_SIF(atchan->per_if)
> +				| ATC_DIF(atchan->mem_if);
>  		break;
>  
>  	default:
> @@ -1190,6 +1191,67 @@ static void atc_free_chan_resources(struct dma_chan *chan)
>  	dev_vdbg(chan2dev(chan), "free_chan_resources: done\n");
>  }
>  
> +static bool at_dma_filter(struct dma_chan *chan, void *slave)
> +{
> +	struct at_dma_slave *atslave = slave;
> +
> +	if (atslave->dma_dev == chan->device->dev) {
> +		chan->private = atslave;
> +		return true;
> +	} else {
> +		return false;
> +	}
> +}
> +
> +#ifdef CONFIG_OF
> +static struct dma_chan *at_dma_xlate(struct of_phandle_args *dma_spec,
> +				     struct of_dma *of_dma)
> +{
> +	struct dma_chan *chan;
> +	struct at_dma_chan *atchan;
> +	struct at_dma_slave *atslave;
> +	dma_cap_mask_t mask;
> +	unsigned int per_id;
> +	struct platform_device *dmac_pdev;
> +
> +	if (dma_spec->args_count != 2)
> +		return NULL;
> +
> +	dmac_pdev = of_find_device_by_node(dma_spec->np);
> +
> +	dma_cap_zero(mask);
> +	dma_cap_set(DMA_SLAVE, mask);
> +
> +	atslave = devm_kzalloc(&dmac_pdev->dev, sizeof(*atslave), GFP_KERNEL);
> +	if (!atslave)
> +		return NULL;
> +	/*
> +	 * We can fill both SRC_PER and DST_PER, one of these fields will be
> +	 * ignored depending on DMA transfer direction.
> +	 */
> +	per_id = dma_spec->args[1];
> +	atslave->cfg = ATC_FIFOCFG_HALFFIFO | ATC_DST_H2SEL_HW
> +		      | ATC_SRC_H2SEL_HW | ATC_DST_PER(per_id)
> +		      | ATC_SRC_PER(per_id);
> +	atslave->dma_dev = &dmac_pdev->dev;
> +
> +	chan = dma_request_channel(mask, at_dma_filter, atslave);
> +	if (!chan)
> +		return NULL;
> +
> +	atchan = to_at_dma_chan(chan);
> +	atchan->per_if = dma_spec->args[0] & 0xff;
> +	atchan->mem_if = (dma_spec->args[0] >> 16) & 0xff;
> +
> +	return chan;
> +}
> +#else
> +static struct dma_chan *at_dma_xlate(struct of_phandle_args *dma_spec,
> +				     struct of_dma *of_dma)
> +{
> +	return NULL;
> +}
> +#endif
>  
>  /*--  Module Management  -----------------------------------------------*/
>  
> @@ -1344,6 +1406,8 @@ static int __init at_dma_probe(struct platform_device *pdev)
>  	for (i = 0; i < plat_dat->nr_channels; i++) {
>  		struct at_dma_chan	*atchan = &atdma->chan[i];
>  
> +		atchan->mem_if = AT_DMA_MEM_IF;
> +		atchan->per_if = AT_DMA_PER_IF;
>  		atchan->chan_common.device = &atdma->dma_common;
>  		dma_cookie_init(&atchan->chan_common);
>  		list_add_tail(&atchan->chan_common.device_node,
> @@ -1390,8 +1454,25 @@ static int __init at_dma_probe(struct platform_device *pdev)
>  
>  	dma_async_device_register(&atdma->dma_common);
>  
> +	/*
> +	 * Do not return an error if the dmac node is not present in order to
> +	 * not break the existing way of requesting channel with
> +	 * dma_request_channel().
> +	 */
> +	if (pdev->dev.of_node) {
> +		err = of_dma_controller_register(pdev->dev.of_node,
> +						 at_dma_xlate, atdma);
> +		if (err) {
> +			dev_err(&pdev->dev, "could not register of_dma_controller\n");
> +			goto err_of_dma_controller_register;
> +		}
> +	}
> +
>  	return 0;
>  
> +err_of_dma_controller_register:
> +	dma_async_device_unregister(&atdma->dma_common);
> +	dma_pool_destroy(atdma->dma_desc_pool);
>  err_pool_create:
>  	platform_set_drvdata(pdev, NULL);
>  	free_irq(platform_get_irq(pdev, 0), atdma);
> diff --git a/drivers/dma/at_hdmac_regs.h b/drivers/dma/at_hdmac_regs.h
> index 0eb3c13..c604d26 100644
> --- a/drivers/dma/at_hdmac_regs.h
> +++ b/drivers/dma/at_hdmac_regs.h
> @@ -220,6 +220,8 @@ enum atc_status {
>   * @device: parent device
>   * @ch_regs: memory mapped register base
>   * @mask: channel index in a mask
> + * @per_if: peripheral interface
> + * @mem_if: memory interface
>   * @status: transmit status information from irq/prep* functions
>   *                to tasklet (use atomic operations)
>   * @tasklet: bottom half to finish transaction work
> @@ -238,6 +240,8 @@ struct at_dma_chan {
>  	struct at_dma		*device;
>  	void __iomem		*ch_regs;
>  	u8			mask;
> +	u8			per_if;
> +	u8			mem_if;
>  	unsigned long		status;
>  	struct tasklet_struct	tasklet;
>  	u32			save_cfg;
> 


-- 
Nicolas Ferre

Re: [PATCH 1/6] at_hdmac: move to generic DMA binding

[Arnd Bergmann]

On Thursday 18 April 2013, Nicolas Ferre wrote:
> Arnd,
> Do you feel like giving your "Acked-by" to this patch? I think that you
> were pretty in line with Ludovic's RFC, so it may be interesting to have
> your support on this...

Yes, it's fine.

Acked-by: Arnd Bergmann <arnd@arndb.de>