usb: dwc2: Move gadget settings into core_params

Move the gadget devicetree settings into the core_params structure and
document them. Then set and check them in params.c, with the addition of
some helper functions, and remove the equivalent code in gadget.c.

Because these parameters came from the standalone s3c driver, they have
a fixed default value rather than an autodetected one. Preserve and
document this behavior to avoid any compatibility issues.

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

3 files changed, 296 insertions, 91 deletions

diff --git a/drivers/usb/dwc2/core.h b/drivers/usb/dwc2/core.h
index b94d80810530..935ef365fece 100644
--- a/drivers/usb/dwc2/core.h
+++ b/drivers/usb/dwc2/core.h
@@ -418,6 +418,21 @@ enum dwc2_ep0_state {
  *			needed.
  *			0 - No (default)
  *			1 - Yes
+ * @g_dma:              If true, enables dma usage on the device. This
+ *                      setting is not auto-detected. It must be
+ *                      explicitly enabled (default: false).
+ * @g_rx_fifo_size:	The periodic rx fifo size for the device, in
+ *			DWORDS from 16-32768 (default: 2048 if
+ *			possible, otherwise autodetect).
+ * @g_np_tx_fifo_size:	The non-periodic tx fifo size for the device in
+ *			DWORDS from 16-32768 (default: 1024 if
+ *			possible, otherwise autodetect).
+ * @g_tx_fifo_size:	An array of TX fifo sizes in dedicated fifo
+ *			mode. Each value corresponds to one EP
+ *			starting from EP1 (max 15 values). Sizes are
+ *			in DWORDS with possible values from from
+ *			16-32768 (default: 256, 256, 256, 256, 768,
+ *			768, 768, 768, 0, 0, 0, 0, 0, 0, 0).
  *
  * The following parameters may be specified when starting the module. These
  * parameters define how the DWC_otg controller should be configured. A
@@ -475,6 +490,15 @@ struct dwc2_core_params {
 	int uframe_sched;
 	int external_id_pin_ctl;
 	int hibernation;
+
+	/*
+	 * The following parameters are *only* set via device
+	 * properties and cannot be set directly in this structure.
+	 */
+	bool g_dma;
+	u16 g_rx_fifo_size;
+	u16 g_np_tx_fifo_size;
+	u32 g_tx_fifo_size[MAX_EPS_CHANNELS];
 };
 
 /**
@@ -857,10 +881,6 @@ struct dwc2_hregs_backup {
  * @ep0_state:          EP0 control transfers state
  * @test_mode:          USB test mode requested by the host
  * @eps:                The endpoints being supplied to the gadget framework
- * @g_using_dma:          Indicate if dma usage is enabled
- * @g_rx_fifo_sz:         Contains rx fifo size value
- * @g_np_g_tx_fifo_sz:      Contains Non-Periodic tx fifo size value
- * @g_tx_fifo_sz:         Contains tx fifo size value per endpoints
  */
 struct dwc2_hsotg {
 	struct device *dev;
@@ -1008,10 +1028,6 @@ struct dwc2_hsotg {
 	unsigned int connected:1;
 	struct dwc2_hsotg_ep *eps_in[MAX_EPS_CHANNELS];
 	struct dwc2_hsotg_ep *eps_out[MAX_EPS_CHANNELS];
-	u32 g_using_dma;
-	u32 g_rx_fifo_sz;
-	u32 g_np_g_tx_fifo_sz;
-	u32 g_tx_fifo_sz[MAX_EPS_CHANNELS];
 #endif /* CONFIG_USB_DWC2_PERIPHERAL || CONFIG_USB_DWC2_DUAL_ROLE */
 };
 
diff --git a/drivers/usb/dwc2/gadget.c b/drivers/usb/dwc2/gadget.c
index 54f69275b61e..8a7fd73721d7 100644
--- a/drivers/usb/dwc2/gadget.c
+++ b/drivers/usb/dwc2/gadget.c
@@ -93,7 +93,7 @@ static void dwc2_hsotg_dump(struct dwc2_hsotg *hsotg);
  */
 static inline bool using_dma(struct dwc2_hsotg *hsotg)
 {
-	return hsotg->g_using_dma;
+	return hsotg->params.g_dma;
 }
 
 /**
@@ -190,16 +190,17 @@ static void dwc2_hsotg_init_fifo(struct dwc2_hsotg *hsotg)
 	unsigned int addr;
 	int timeout;
 	u32 val;
+	u32 *txfsz = hsotg->params.g_tx_fifo_size;
 
 	/* Reset fifo map if not correctly cleared during previous session */
 	WARN_ON(hsotg->fifo_map);
 	hsotg->fifo_map = 0;
 
 	/* set RX/NPTX FIFO sizes */
-	dwc2_writel(hsotg->g_rx_fifo_sz, hsotg->regs + GRXFSIZ);
-	dwc2_writel((hsotg->g_rx_fifo_sz << FIFOSIZE_STARTADDR_SHIFT) |
-		(hsotg->g_np_g_tx_fifo_sz << FIFOSIZE_DEPTH_SHIFT),
-		hsotg->regs + GNPTXFSIZ);
+	dwc2_writel(hsotg->params.g_rx_fifo_size, hsotg->regs + GRXFSIZ);
+	dwc2_writel((hsotg->params.g_rx_fifo_size << FIFOSIZE_STARTADDR_SHIFT) |
+		    (hsotg->params.g_np_tx_fifo_size << FIFOSIZE_DEPTH_SHIFT),
+		    hsotg->regs + GNPTXFSIZ);
 
 	/*
 	 * arange all the rest of the TX FIFOs, as some versions of this
@@ -209,7 +210,7 @@ static void dwc2_hsotg_init_fifo(struct dwc2_hsotg *hsotg)
 	 */
 
 	/* start at the end of the GNPTXFSIZ, rounded up */
-	addr = hsotg->g_rx_fifo_sz + hsotg->g_np_g_tx_fifo_sz;
+	addr = hsotg->params.g_rx_fifo_size + hsotg->params.g_np_tx_fifo_size;
 
 	/*
 	 * Configure fifos sizes from provided configuration and assign
@@ -217,15 +218,16 @@ static void dwc2_hsotg_init_fifo(struct dwc2_hsotg *hsotg)
 	 * given endpoint.
 	 */
 	for (ep = 1; ep < MAX_EPS_CHANNELS; ep++) {
-		if (!hsotg->g_tx_fifo_sz[ep])
+		if (!txfsz[ep])
 			continue;
 		val = addr;
-		val |= hsotg->g_tx_fifo_sz[ep] << FIFOSIZE_DEPTH_SHIFT;
-		WARN_ONCE(addr + hsotg->g_tx_fifo_sz[ep] > hsotg->fifo_mem,
+		val |= txfsz[ep] << FIFOSIZE_DEPTH_SHIFT;
+		WARN_ONCE(addr + txfsz[ep] > hsotg->fifo_mem,
 			  "insufficient fifo memory");
-		addr += hsotg->g_tx_fifo_sz[ep];
+		addr += txfsz[ep];
 
 		dwc2_writel(val, hsotg->regs + DPTXFSIZN(ep));
+		val = dwc2_readl(hsotg->regs + DPTXFSIZN(ep));
 	}
 
 	/*
@@ -3800,51 +3802,6 @@ static void dwc2_hsotg_dump(struct dwc2_hsotg *hsotg)
 #endif
 }
 
-#ifdef CONFIG_OF
-static void dwc2_hsotg_of_probe(struct dwc2_hsotg *hsotg)
-{
-	struct device_node *np = hsotg->dev->of_node;
-	u32 len = 0;
-	u32 i = 0;
-
-	/* Enable dma if requested in device tree */
-	hsotg->g_using_dma = of_property_read_bool(np, "g-use-dma");
-
-	/*
-	* Register TX periodic fifo size per endpoint.
-	* EP0 is excluded since it has no fifo configuration.
-	*/
-	if (!of_find_property(np, "g-tx-fifo-size", &len))
-		goto rx_fifo;
-
-	len /= sizeof(u32);
-
-	/* Read tx fifo sizes other than ep0 */
-	if (of_property_read_u32_array(np, "g-tx-fifo-size",
-						&hsotg->g_tx_fifo_sz[1], len))
-		goto rx_fifo;
-
-	/* Add ep0 */
-	len++;
-
-	/* Make remaining TX fifos unavailable */
-	if (len < MAX_EPS_CHANNELS) {
-		for (i = len; i < MAX_EPS_CHANNELS; i++)
-			hsotg->g_tx_fifo_sz[i] = 0;
-	}
-
-rx_fifo:
-	/* Register RX fifo size */
-	of_property_read_u32(np, "g-rx-fifo-size", &hsotg->g_rx_fifo_sz);
-
-	/* Register NPTX fifo size */
-	of_property_read_u32(np, "g-np-tx-fifo-size",
-						&hsotg->g_np_g_tx_fifo_sz);
-}
-#else
-static inline void dwc2_hsotg_of_probe(struct dwc2_hsotg *hsotg) { }
-#endif
-
 /**
  * dwc2_gadget_init - init function for gadget
  * @dwc2: The data structure for the DWC2 driver.
@@ -3855,33 +3812,11 @@ int dwc2_gadget_init(struct dwc2_hsotg *hsotg, int irq)
 	struct device *dev = hsotg->dev;
 	int epnum;
 	int ret;
-	int i;
-	u32 p_tx_fifo[] = DWC2_G_P_LEGACY_TX_FIFO_SIZE;
-
-	/* Initialize to legacy fifo configuration values */
-	hsotg->g_rx_fifo_sz = 2048;
-	hsotg->g_np_g_tx_fifo_sz = 1024;
-	memcpy(&hsotg->g_tx_fifo_sz[1], p_tx_fifo, sizeof(p_tx_fifo));
-	/* Device tree specific probe */
-	dwc2_hsotg_of_probe(hsotg);
-
-	/* Check against largest possible value. */
-	if (hsotg->g_np_g_tx_fifo_sz >
-	    hsotg->hw_params.dev_nperio_tx_fifo_size) {
-		dev_warn(dev, "Specified GNPTXFDEP=%d > %d\n",
-			 hsotg->g_np_g_tx_fifo_sz,
-			 hsotg->hw_params.dev_nperio_tx_fifo_size);
-		hsotg->g_np_g_tx_fifo_sz =
-			hsotg->hw_params.dev_nperio_tx_fifo_size;
-	}
 
 	/* Dump fifo information */
 	dev_dbg(dev, "NonPeriodic TXFIFO size: %d\n",
-						hsotg->g_np_g_tx_fifo_sz);
-	dev_dbg(dev, "RXFIFO size: %d\n", hsotg->g_rx_fifo_sz);
-	for (i = 0; i < MAX_EPS_CHANNELS; i++)
-		dev_dbg(dev, "Periodic TXFIFO%2d size: %d\n", i,
-						hsotg->g_tx_fifo_sz[i]);
+		hsotg->params.g_np_tx_fifo_size);
+	dev_dbg(dev, "RXFIFO size: %d\n", hsotg->params.g_rx_fifo_size);
 
 	hsotg->gadget.max_speed = USB_SPEED_HIGH;
 	hsotg->gadget.ops = &dwc2_hsotg_gadget_ops;
diff --git a/drivers/usb/dwc2/params.c b/drivers/usb/dwc2/params.c
index 719205ab09a2..c96ae72f4f0e 100644
--- a/drivers/usb/dwc2/params.c
+++ b/drivers/usb/dwc2/params.c
@@ -249,6 +249,187 @@ const struct of_device_id dwc2_of_match_table[] = {
 };
 MODULE_DEVICE_TABLE(of, dwc2_of_match_table);
 
+static void dwc2_get_device_property(struct dwc2_hsotg *hsotg,
+				     char *property, u8 size, u64 *value)
+{
+	u8 val8;
+	u16 val16;
+	u32 val32;
+
+	switch (size) {
+	case 0:
+		*value = device_property_read_bool(hsotg->dev, property);
+		break;
+	case 1:
+		if (device_property_read_u8(hsotg->dev, property, &val8))
+			return;
+
+		*value = val8;
+		break;
+	case 2:
+		if (device_property_read_u16(hsotg->dev, property, &val16))
+			return;
+
+		*value = val16;
+		break;
+	case 4:
+		if (device_property_read_u32(hsotg->dev, property, &val32))
+			return;
+
+		*value = val32;
+		break;
+	case 8:
+		if (device_property_read_u64(hsotg->dev, property, value))
+			return;
+
+		break;
+	default:
+		/*
+		 * The size is checked by the only function that calls
+		 * this so this should never happen.
+		 */
+		WARN_ON(1);
+		return;
+	}
+}
+
+static void dwc2_set_core_param(void *param, u8 size, u64 value)
+{
+	switch (size) {
+	case 0:
+		*((bool *)param) = !!value;
+		break;
+	case 1:
+		*((u8 *)param) = (u8)value;
+		break;
+	case 2:
+		*((u16 *)param) = (u16)value;
+		break;
+	case 4:
+		*((u32 *)param) = (u32)value;
+		break;
+	case 8:
+		*((u64 *)param) = (u64)value;
+		break;
+	default:
+		/*
+		 * The size is checked by the only function that calls
+		 * this so this should never happen.
+		 */
+		WARN_ON(1);
+		return;
+	}
+}
+
+/**
+ * dwc2_set_param() - Set a core parameter
+ *
+ * @hsotg: Programming view of the DWC_otg controller
+ * @param: Pointer to the parameter to set
+ * @lookup: True if the property should be looked up
+ * @property: The device property to read
+ * @legacy: The param value to set if @property is not available. This
+ *          will typically be the legacy value set in the static
+ *          params structure.
+ * @def: The default value
+ * @min: The minimum value
+ * @max: The maximum value
+ * @size: The size of the core parameter in bytes, or 0 for bool.
+ *
+ * This function looks up @property and sets the @param to that value.
+ * If the property doesn't exist it uses the passed-in @value. It will
+ * verify that the value falls between @min and @max. If it doesn't,
+ * it will output an error and set the parameter to either @def or,
+ * failing that, to @min.
+ *
+ * The @size is used to write to @param and to query the device
+ * properties so that this same function can be used with different
+ * types of parameters.
+ */
+static void dwc2_set_param(struct dwc2_hsotg *hsotg, void *param,
+			   bool lookup, char *property, u64 legacy,
+			   u64 def, u64 min, u64 max, u8 size)
+{
+	u64 sizemax;
+	u64 value;
+
+	if (WARN_ON(!hsotg || !param || !property))
+		return;
+
+	if (WARN((size > 8) || ((size & (size - 1)) != 0),
+		 "Invalid size %d for %s\n", size, property))
+		return;
+
+	dev_vdbg(hsotg->dev, "%s: Setting %s: legacy=%llu, def=%llu, min=%llu, max=%llu, size=%d\n",
+		 __func__, property, legacy, def, min, max, size);
+
+	sizemax = (1ULL << (size * 8)) - 1;
+	value = legacy;
+
+	/* Override legacy settings. */
+	if (lookup)
+		dwc2_get_device_property(hsotg, property, size, &value);
+
+	/*
+	 * While the value is not valid, try setting it to the default
+	 * value, and failing that, set it to the minimum.
+	 */
+	while ((value < min) || (value > max)) {
+		/* Print an error unless the value is set to auto. */
+		if (value != sizemax)
+			dev_err(hsotg->dev, "Invalid value %llu for param %s\n",
+				value, property);
+
+		/*
+		 * If we are already the default, just set it to the
+		 * minimum.
+		 */
+		if (value == def) {
+			dev_vdbg(hsotg->dev, "%s: setting value to min=%llu\n",
+				 __func__, min);
+			value = min;
+			break;
+		}
+
+		/* Try the default value */
+		dev_vdbg(hsotg->dev, "%s: setting value to default=%llu\n",
+			 __func__, def);
+		value = def;
+	}
+
+	dev_dbg(hsotg->dev, "Setting %s to %llu\n", property, value);
+	dwc2_set_core_param(param, size, value);
+}
+
+/**
+ * dwc2_set_param_u16() - Set a u16 parameter
+ *
+ * See dwc2_set_param().
+ */
+static void dwc2_set_param_u16(struct dwc2_hsotg *hsotg, u16 *param,
+			       bool lookup, char *property, u16 legacy,
+			       u16 def, u16 min, u16 max)
+{
+	dwc2_set_param(hsotg, param, lookup, property,
+		       legacy, def, min, max, 2);
+}
+
+/**
+ * dwc2_set_param_bool() - Set a bool parameter
+ *
+ * See dwc2_set_param().
+ *
+ * Note: there is no 'legacy' argument here because there is no legacy
+ * source of bool params.
+ */
+static void dwc2_set_param_bool(struct dwc2_hsotg *hsotg, bool *param,
+				bool lookup, char *property,
+				bool def, bool min, bool max)
+{
+	dwc2_set_param(hsotg, param, lookup, property,
+		       def, def, min, max, 0);
+}
+
 #define DWC2_OUT_OF_BOUNDS(a, b, c)	((a) < (b) || (a) > (c))
 
 /* Parameter access functions */
@@ -897,14 +1078,52 @@ static void dwc2_set_param_hibernation(struct dwc2_hsotg *hsotg,
 	hsotg->params.hibernation = val;
 }
 
-/*
- * This function is called during module intialization to pass module parameters
- * for the DWC_otg core.
+static void dwc2_set_param_tx_fifo_sizes(struct dwc2_hsotg *hsotg)
+{
+	int i;
+	int num;
+	char *property = "g-tx-fifo-size";
+	struct dwc2_core_params *p = &hsotg->params;
+
+	memset(p->g_tx_fifo_size, 0, sizeof(p->g_tx_fifo_size));
+
+	/* Read tx fifo sizes */
+	num = device_property_read_u32_array(hsotg->dev, property, NULL, 0);
+
+	if (num > 0) {
+		device_property_read_u32_array(hsotg->dev, property,
+					       &p->g_tx_fifo_size[1],
+					       num);
+	} else {
+		u32 p_tx_fifo[] = DWC2_G_P_LEGACY_TX_FIFO_SIZE;
+
+		memcpy(&p->g_tx_fifo_size[1],
+		       p_tx_fifo,
+		       sizeof(p_tx_fifo));
+
+		num = ARRAY_SIZE(p_tx_fifo);
+	}
+
+	for (i = 0; i < num; i++) {
+		if ((i + 1) >= ARRAY_SIZE(p->g_tx_fifo_size))
+			break;
+
+		dev_dbg(hsotg->dev, "Setting %s[%d] to %d\n",
+			property, i + 1, p->g_tx_fifo_size[i + 1]);
+	}
+}
+
+/**
+ * dwc2_set_parameters() - Set all core parameters.
+ *
+ * @hsotg: Programming view of the DWC_otg controller
+ * @params: The parameters to set
  */
 static void dwc2_set_parameters(struct dwc2_hsotg *hsotg,
 				const struct dwc2_core_params *params)
 {
-	dev_dbg(hsotg->dev, "%s()\n", __func__);
+	struct dwc2_hw_params *hw = &hsotg->hw_params;
+	struct dwc2_core_params *p = &hsotg->params;
 
 	dwc2_set_param_otg_cap(hsotg, params->otg_cap);
 	dwc2_set_param_dma_enable(hsotg, params->dma_enable);
@@ -944,6 +1163,41 @@ static void dwc2_set_parameters(struct dwc2_hsotg *hsotg,
 	dwc2_set_param_uframe_sched(hsotg, params->uframe_sched);
 	dwc2_set_param_external_id_pin_ctl(hsotg, params->external_id_pin_ctl);
 	dwc2_set_param_hibernation(hsotg, params->hibernation);
+
+	/*
+	 * Set devicetree-only parameters. These parameters do not
+	 * take any values from @params.
+	 */
+	if ((hsotg->dr_mode == USB_DR_MODE_PERIPHERAL) ||
+	    (hsotg->dr_mode == USB_DR_MODE_OTG)) {
+		dev_dbg(hsotg->dev, "Setting peripheral device properties\n");
+
+		dwc2_set_param_bool(hsotg, &p->g_dma, true, "g-use-dma",
+				    false, false,
+				    hsotg->hw_params.arch !=
+				    GHWCFG2_SLAVE_ONLY_ARCH);
+
+		/*
+		 * The values for g_rx_fifo_size (2048) and
+		 * g_np_tx_fifo_size (1024) come from the legacy s3c
+		 * gadget driver. These defaults have been hard-coded
+		 * for some time so many platforms depend on these
+		 * values. Leave them as defaults for now and only
+		 * auto-detect if the hardware does not support the
+		 * default.
+		 */
+		dwc2_set_param_u16(hsotg, &p->g_rx_fifo_size,
+				   true, "g-rx-fifo-size", 2048,
+				   hw->rx_fifo_size,
+				   16, hw->rx_fifo_size);
+
+		dwc2_set_param_u16(hsotg, &p->g_np_tx_fifo_size,
+				   true, "g-np-tx-fifo-size", 1024,
+				   hw->dev_nperio_tx_fifo_size,
+				   16, hw->dev_nperio_tx_fifo_size);
+
+		dwc2_set_param_tx_fifo_sizes(hsotg);
+	}
 }
 
 /*