commit d078cd1b4185134fe861e2b16a40ba14efb307b7
author Zidan Wang <zidan.wang@freescale.com> Thu Jul 23 11:40:49 2015 +0800
committer Vinod Koul <vinod.koul@intel.com> Wed Aug 19 21:28:55 2015 +0530
tree afd375b22c6a533c77ef61cce371bcbc148a2c38
parent e900c30dc1bb0cbc07708e9be1188f531632b2ef

dmaengine: imx-sdma: Add imx6sx platform support

The new Solo X has more requirements for SDMA events. So it creates
a event mux to remap most of event numbers in GPR (General Purpose
Register). If we want to use SDMA support for those module who do
not get the even number as default, we need to configure GPR first.

Thus this patch adds this support of GPR event remapping configuration
to the SDMA driver.

Signed-off-by: Zidan Wang <zidan.wang@freescale.com>
Signed-off-by: Vinod Koul <vinod.koul@intel.com>

drivers/dma/imx-sdma.c

diff --git a/drivers/dma/imx-sdma.c b/drivers/dma/imx-sdma.c
index 34dece3..acf1e2f 100644
--- a/drivers/dma/imx-sdma.c
+++ b/drivers/dma/imx-sdma.c
@@ -42,6 +42,9 @@
 #include <asm/irq.h>
 #include <linux/platform_data/dma-imx-sdma.h>
 #include <linux/platform_data/dma-imx.h>
+#include <linux/regmap.h>
+#include <linux/mfd/syscon.h>
+#include <linux/mfd/syscon/imx6q-iomuxc-gpr.h>
 
 #include "dmaengine.h"
 
@@ -1447,6 +1450,72 @@
 	release_firmware(fw);
 }
 
+#define EVENT_REMAP_CELLS 3
+
+static int __init sdma_event_remap(struct sdma_engine *sdma)
+{
+	struct device_node *np = sdma->dev->of_node;
+	struct device_node *gpr_np = of_parse_phandle(np, "gpr", 0);
+	struct property *event_remap;
+	struct regmap *gpr;
+	char propname[] = "fsl,sdma-event-remap";
+	u32 reg, val, shift, num_map, i;
+	int ret = 0;
+
+	if (IS_ERR(np) || IS_ERR(gpr_np))
+		goto out;
+
+	event_remap = of_find_property(np, propname, NULL);
+	num_map = event_remap ? (event_remap->length / sizeof(u32)) : 0;
+	if (!num_map) {
+		dev_warn(sdma->dev, "no event needs to be remapped\n");
+		goto out;
+	} else if (num_map % EVENT_REMAP_CELLS) {
+		dev_err(sdma->dev, "the property %s must modulo %d\n",
+				propname, EVENT_REMAP_CELLS);
+		ret = -EINVAL;
+		goto out;
+	}
+
+	gpr = syscon_node_to_regmap(gpr_np);
+	if (IS_ERR(gpr)) {
+		dev_err(sdma->dev, "failed to get gpr regmap\n");
+		ret = PTR_ERR(gpr);
+		goto out;
+	}
+
+	for (i = 0; i < num_map; i += EVENT_REMAP_CELLS) {
+		ret = of_property_read_u32_index(np, propname, i, &reg);
+		if (ret) {
+			dev_err(sdma->dev, "failed to read property %s index %d\n",
+					propname, i);
+			goto out;
+		}
+
+		ret = of_property_read_u32_index(np, propname, i + 1, &shift);
+		if (ret) {
+			dev_err(sdma->dev, "failed to read property %s index %d\n",
+					propname, i + 1);
+			goto out;
+		}
+
+		ret = of_property_read_u32_index(np, propname, i + 2, &val);
+		if (ret) {
+			dev_err(sdma->dev, "failed to read property %s index %d\n",
+					propname, i + 2);
+			goto out;
+		}
+
+		regmap_update_bits(gpr, reg, BIT(shift), val << shift);
+	}
+
+out:
+	if (!IS_ERR(gpr_np))
+		of_node_put(gpr_np);
+
+	return ret;
+}
+
 static int sdma_get_firmware(struct sdma_engine *sdma,
 		const char *fw_name)
 {
@@ -1671,6 +1740,10 @@
 	if (ret)
 		goto err_init;
 
+	ret = sdma_event_remap(sdma);
+	if (ret)
+		goto err_init;
+
 	if (sdma->drvdata->script_addrs)
 		sdma_add_scripts(sdma, sdma->drvdata->script_addrs);
 	if (pdata && pdata->script_addrs)