usb: dwc2: Get host DMA device properties

The driver will automatically enable host DMA and use it if available.
This is consistent with the behavior of all existing platforms.

Read in the "snps,host-dma-disable" device property to disable it.

Signed-off-by: John Youn <johnyoun@synopsys.com>
Signed-off-by: Felipe Balbi <felipe.balbi@linux.intel.com>

drivers/usb/dwc2/core.h

@@ -451,7 +451,6 @@ struct dwc2_core_params {
 #define DWC2_CAP_PARAM_NO_HNP_SRP_CAPABLE	2
 
 	int otg_ver;
-	int host_dma;
 	int dma_desc_enable;
 	int dma_desc_fs_enable;
 	int speed;
@@ -495,6 +494,11 @@ struct dwc2_core_params {
 	 * The following parameters are *only* set via device
 	 * properties and cannot be set directly in this structure.
 	 */
+
+	/* Host parameters */
+	bool host_dma;
+
+	/* Gadget parameters */
 	bool g_dma;
 	u16 g_rx_fifo_size;
 	u16 g_np_tx_fifo_size;

drivers/usb/dwc2/params.c

@@ -41,7 +41,6 @@
 static const struct dwc2_core_params params_hi6220 = {
 	.otg_cap			= 2,	/* No HNP/SRP capable */
 	.otg_ver			= 0,	/* 1.3 */
-	.host_dma			= 1,
 	.dma_desc_enable		= 0,
 	.dma_desc_fs_enable		= 0,
 	.speed				= 0,	/* High Speed */
@@ -73,7 +72,6 @@ static const struct dwc2_core_params params_hi6220 = {
 static const struct dwc2_core_params params_bcm2835 = {
 	.otg_cap			= 0,	/* HNP/SRP capable */
 	.otg_ver			= 0,	/* 1.3 */
-	.host_dma			= 1,
 	.dma_desc_enable		= 0,
 	.dma_desc_fs_enable		= 0,
 	.speed				= 0,	/* High Speed */
@@ -104,7 +102,6 @@ static const struct dwc2_core_params params_bcm2835 = {
 static const struct dwc2_core_params params_rk3066 = {
 	.otg_cap			= 2,	/* non-HNP/non-SRP */
 	.otg_ver			= -1,
-	.host_dma			= -1,
 	.dma_desc_enable		= 0,
 	.dma_desc_fs_enable		= 0,
 	.speed				= -1,
@@ -136,7 +133,6 @@ static const struct dwc2_core_params params_rk3066 = {
 static const struct dwc2_core_params params_ltq = {
 	.otg_cap			= 2,	/* non-HNP/non-SRP */
 	.otg_ver			= -1,
-	.host_dma			= -1,
 	.dma_desc_enable		= -1,
 	.dma_desc_fs_enable		= -1,
 	.speed				= -1,
@@ -168,7 +164,6 @@ static const struct dwc2_core_params params_ltq = {
 static const struct dwc2_core_params params_amlogic = {
 	.otg_cap			= DWC2_CAP_PARAM_NO_HNP_SRP_CAPABLE,
 	.otg_ver			= -1,
-	.host_dma			= 1,
 	.dma_desc_enable		= 0,
 	.dma_desc_fs_enable		= 0,
 	.speed				= DWC2_SPEED_PARAM_HIGH,
@@ -200,7 +195,6 @@ static const struct dwc2_core_params params_amlogic = {
 static const struct dwc2_core_params params_default = {
 	.otg_cap			= -1,
 	.otg_ver			= -1,
-	.host_dma			= -1,
 
 	/*
 	 * Disable descriptor dma mode by default as the HW can support
@@ -486,27 +480,6 @@ static void dwc2_set_param_otg_cap(struct dwc2_hsotg *hsotg, int val)
 	hsotg->params.otg_cap = val;
 }
 
-static void dwc2_set_param_host_dma(struct dwc2_hsotg *hsotg, int val)
-{
-	int valid = 1;
-
-	if (val > 0 && hsotg->hw_params.arch == GHWCFG2_SLAVE_ONLY_ARCH)
-		valid = 0;
-	if (val < 0)
-		valid = 0;
-
-	if (!valid) {
-		if (val >= 0)
-			dev_err(hsotg->dev,
-				"%d invalid for host_dma parameter. Check HW configuration.\n",
-				val);
-		val = hsotg->hw_params.arch != GHWCFG2_SLAVE_ONLY_ARCH;
-		dev_dbg(hsotg->dev, "Setting host_dma to %d\n", val);
-	}
-
-	hsotg->params.host_dma = val;
-}
-
 static void dwc2_set_param_dma_desc_enable(struct dwc2_hsotg *hsotg, int val)
 {
 	int valid = 1;
@@ -1124,11 +1097,27 @@ static void dwc2_set_parameters(struct dwc2_hsotg *hsotg,
 {
 	struct dwc2_hw_params *hw = &hsotg->hw_params;
 	struct dwc2_core_params *p = &hsotg->params;
+	bool dma_capable = !(hw->arch == GHWCFG2_SLAVE_ONLY_ARCH);
 
 	dwc2_set_param_otg_cap(hsotg, params->otg_cap);
-	dwc2_set_param_host_dma(hsotg, params->host_dma);
 	dwc2_set_param_dma_desc_enable(hsotg, params->dma_desc_enable);
 	dwc2_set_param_dma_desc_fs_enable(hsotg, params->dma_desc_fs_enable);
+
+	if ((hsotg->dr_mode == USB_DR_MODE_HOST) ||
+	    (hsotg->dr_mode == USB_DR_MODE_OTG)) {
+		bool disable;
+
+		dev_dbg(hsotg->dev, "Setting HOST parameters\n");
+
+		disable = device_property_read_bool(hsotg->dev,
+						    "snps,host-dma-disable");
+
+		dwc2_set_param_bool(hsotg, &p->host_dma,
+				    false, "host-dma",
+				    !disable, false,
+				    dma_capable);
+	}
+
 	dwc2_set_param_host_support_fs_ls_low_power(hsotg,
 			params->host_support_fs_ls_low_power);
 	dwc2_set_param_enable_dynamic_fifo(hsotg,
@@ -1174,8 +1163,7 @@ static void dwc2_set_parameters(struct dwc2_hsotg *hsotg,
 
 		dwc2_set_param_bool(hsotg, &p->g_dma, true, "g-use-dma",
 				    false, false,
-				    hsotg->hw_params.arch !=
-				    GHWCFG2_SLAVE_ONLY_ARCH);
+				    dma_capable);
 
 		/*
 		 * The values for g_rx_fifo_size (2048) and