1 files changed, 134 insertions, 61 deletions

diff --git a/drivers/net/can/sun4i_can.c b/drivers/net/can/sun4i_can.c
index 68ef0a4cd821..af52285d5a4e 100644
--- a/drivers/net/can/sun4i_can.c
+++ b/drivers/net/can/sun4i_can.c
@@ -51,16 +51,16 @@
 #include <linux/can.h>
 #include <linux/can/dev.h>
 #include <linux/can/error.h>
-#include <linux/can/led.h>
 #include <linux/clk.h>
 #include <linux/delay.h>
+#include <linux/ethtool.h>
 #include <linux/interrupt.h>
 #include <linux/init.h>
 #include <linux/io.h>
 #include <linux/module.h>
 #include <linux/of.h>
-#include <linux/of_device.h>
 #include <linux/platform_device.h>
+#include <linux/reset.h>
 
 #define DRV_NAME "sun4i_can"
 
@@ -90,6 +90,8 @@
 #define SUN4I_REG_BUF12_ADDR	0x0070	/* CAN Tx/Rx Buffer 12 */
 #define SUN4I_REG_ACPC_ADDR	0x0040	/* CAN Acceptance Code 0 */
 #define SUN4I_REG_ACPM_ADDR	0x0044	/* CAN Acceptance Mask 0 */
+#define SUN4I_REG_ACPC_ADDR_D1	0x0028	/* CAN Acceptance Code 0 on the D1 */
+#define SUN4I_REG_ACPM_ADDR_D1	0x002C	/* CAN Acceptance Mask 0 on the D1 */
 #define SUN4I_REG_RBUF_RBACK_START_ADDR	0x0180	/* CAN transmit buffer start */
 #define SUN4I_REG_RBUF_RBACK_END_ADDR	0x01b0	/* CAN transmit buffer end */
 
@@ -200,11 +202,24 @@
 #define SUN4I_CAN_MAX_IRQ	20
 #define SUN4I_MODE_MAX_RETRIES	100
 
+/**
+ * struct sun4ican_quirks - Differences between SoC variants.
+ *
+ * @has_reset: SoC needs reset deasserted.
+ * @acp_offset: Offset of ACPC and ACPM registers
+ */
+struct sun4ican_quirks {
+	bool has_reset;
+	int acp_offset;
+};
+
 struct sun4ican_priv {
 	struct can_priv can;
 	void __iomem *base;
 	struct clk *clk;
+	struct reset_control *reset;
 	spinlock_t cmdreg_lock;	/* lock for concurrent cmd register writes */
+	int acp_offset;
 };
 
 static const struct can_bittiming_const sun4ican_bittiming_const = {
@@ -327,8 +342,8 @@ static int sun4i_can_start(struct net_device *dev)
 	}
 
 	/* set filters - we accept all */
-	writel(0x00000000, priv->base + SUN4I_REG_ACPC_ADDR);
-	writel(0xFFFFFFFF, priv->base + SUN4I_REG_ACPM_ADDR);
+	writel(0x00000000, priv->base + SUN4I_REG_ACPC_ADDR + priv->acp_offset);
+	writel(0xFFFFFFFF, priv->base + SUN4I_REG_ACPM_ADDR + priv->acp_offset);
 
 	/* clear error counters and error code capture */
 	writel(0, priv->base + SUN4I_REG_ERRC_ADDR);
@@ -342,7 +357,7 @@ static int sun4i_can_start(struct net_device *dev)
 
 	/* enter the selected mode */
 	mod_reg_val = readl(priv->base + SUN4I_REG_MSEL_ADDR);
-	if (priv->can.ctrlmode & CAN_CTRLMODE_PRESUME_ACK)
+	if (priv->can.ctrlmode & CAN_CTRLMODE_LOOPBACK)
 		mod_reg_val |= SUN4I_MSEL_LOOPBACK_MODE;
 	else if (priv->can.ctrlmode & CAN_CTRLMODE_LISTENONLY)
 		mod_reg_val |= SUN4I_MSEL_LISTEN_ONLY_MODE;
@@ -409,7 +424,7 @@ static int sun4ican_set_mode(struct net_device *dev, enum can_mode mode)
  * xx xx xx xx         ff         ll 00 11 22 33 44 55 66 77
  * [ can_id ] [flags] [len] [can data (up to 8 bytes]
  */
-static int sun4ican_start_xmit(struct sk_buff *skb, struct net_device *dev)
+static netdev_tx_t sun4ican_start_xmit(struct sk_buff *skb, struct net_device *dev)
 {
 	struct sun4ican_priv *priv = netdev_priv(dev);
 	struct can_frame *cf = (struct can_frame *)skb->data;
@@ -418,13 +433,13 @@ static int sun4ican_start_xmit(struct sk_buff *skb, struct net_device *dev)
 	canid_t id;
 	int i;
 
-	if (can_dropped_invalid_skb(dev, skb))
+	if (can_dev_dropped_skb(dev, skb))
 		return NETDEV_TX_OK;
 
 	netif_stop_queue(dev);
 
 	id = cf->can_id;
-	dlc = cf->can_dlc;
+	dlc = cf->len;
 	msg_flag_n = dlc;
 
 	if (id & CAN_RTR_FLAG)
@@ -448,7 +463,7 @@ static int sun4ican_start_xmit(struct sk_buff *skb, struct net_device *dev)
 
 	writel(msg_flag_n, priv->base + SUN4I_REG_BUF0_ADDR);
 
-	can_put_echo_skb(skb, dev, 0);
+	can_put_echo_skb(skb, dev, 0, 0);
 
 	if (priv->can.ctrlmode & CAN_CTRLMODE_LOOPBACK)
 		sun4i_can_write_cmdreg(priv, SUN4I_CMD_SELF_RCV_REQ);
@@ -475,7 +490,7 @@ static void sun4i_can_rx(struct net_device *dev)
 		return;
 
 	fi = readl(priv->base + SUN4I_REG_BUF0_ADDR);
-	cf->can_dlc = get_can_dlc(fi & 0x0F);
+	cf->len = can_cc_dlc2len(fi & 0x0F);
 	if (fi & SUN4I_MSG_EFF_FLAG) {
 		dreg = SUN4I_REG_BUF5_ADDR;
 		id = (readl(priv->base + SUN4I_REG_BUF1_ADDR) << 21) |
@@ -490,21 +505,21 @@ static void sun4i_can_rx(struct net_device *dev)
 	}
 
 	/* remote frame ? */
-	if (fi & SUN4I_MSG_RTR_FLAG)
+	if (fi & SUN4I_MSG_RTR_FLAG) {
 		id |= CAN_RTR_FLAG;
-	else
-		for (i = 0; i < cf->can_dlc; i++)
+	} else {
+		for (i = 0; i < cf->len; i++)
 			cf->data[i] = readl(priv->base + dreg + i * 4);
 
+		stats->rx_bytes += cf->len;
+	}
+	stats->rx_packets++;
+
 	cf->can_id = id;
 
 	sun4i_can_write_cmdreg(priv, SUN4I_CMD_RELEASE_RBUF);
 
-	stats->rx_packets++;
-	stats->rx_bytes += cf->can_dlc;
 	netif_rx(skb);
-
-	can_led_event(dev, CAN_LED_EVENT_RX);
 }
 
 static int sun4i_can_err(struct net_device *dev, u8 isrc, u8 status)
@@ -525,11 +540,6 @@ static int sun4i_can_err(struct net_device *dev, u8 isrc, u8 status)
 	rxerr = (errc >> 16) & 0xFF;
 	txerr = errc & 0xFF;
 
-	if (skb) {
-		cf->data[6] = txerr;
-		cf->data[7] = rxerr;
-	}
-
 	if (isrc & SUN4I_INT_DATA_OR) {
 		/* data overrun interrupt */
 		netdev_dbg(dev, "data overrun interrupt\n");
@@ -539,6 +549,13 @@ static int sun4i_can_err(struct net_device *dev, u8 isrc, u8 status)
 		}
 		stats->rx_over_errors++;
 		stats->rx_errors++;
+
+		/* reset the CAN IP by entering reset mode
+		 * ignoring timeout error
+		 */
+		set_reset_mode(dev);
+		set_normal_mode(dev);
+
 		/* clear bit */
 		sun4i_can_write_cmdreg(priv, SUN4I_CMD_CLEAR_OR_FLAG);
 	}
@@ -553,15 +570,18 @@ static int sun4i_can_err(struct net_device *dev, u8 isrc, u8 status)
 		else
 			state = CAN_STATE_ERROR_ACTIVE;
 	}
+	if (likely(skb) && state != CAN_STATE_BUS_OFF) {
+		cf->can_id |= CAN_ERR_CNT;
+		cf->data[6] = txerr;
+		cf->data[7] = rxerr;
+	}
 	if (isrc & SUN4I_INT_BUS_ERR) {
 		/* bus error interrupt */
 		netdev_dbg(dev, "bus error interrupt\n");
 		priv->can.can_stats.bus_error++;
-		stats->rx_errors++;
+		ecc = readl(priv->base + SUN4I_REG_STA_ADDR);
 
 		if (likely(skb)) {
-			ecc = readl(priv->base + SUN4I_REG_STA_ADDR);
-
 			cf->can_id |= CAN_ERR_PROT | CAN_ERR_BUSERROR;
 
 			switch (ecc & SUN4I_STA_MASK_ERR) {
@@ -579,9 +599,15 @@ static int sun4i_can_err(struct net_device *dev, u8 isrc, u8 status)
 					       >> 16;
 				break;
 			}
-			/* error occurred during transmission? */
-			if ((ecc & SUN4I_STA_ERR_DIR) == 0)
+		}
+
+		/* error occurred during transmission? */
+		if ((ecc & SUN4I_STA_ERR_DIR) == 0) {
+			if (likely(skb))
 				cf->data[2] |= CAN_ERR_PROT_TX;
+			stats->tx_errors++;
+		} else {
+			stats->rx_errors++;
 		}
 	}
 	if (isrc & SUN4I_INT_ERR_PASSIVE) {
@@ -597,7 +623,6 @@ static int sun4i_can_err(struct net_device *dev, u8 isrc, u8 status)
 		netdev_dbg(dev, "arbitration lost interrupt\n");
 		alc = readl(priv->base + SUN4I_REG_STA_ADDR);
 		priv->can.can_stats.arbitration_lost++;
-		stats->tx_errors++;
 		if (likely(skb)) {
 			cf->can_id |= CAN_ERR_LOSTARB;
 			cf->data[0] = (alc >> 8) & 0x1f;
@@ -608,21 +633,18 @@ static int sun4i_can_err(struct net_device *dev, u8 isrc, u8 status)
 		tx_state = txerr >= rxerr ? state : 0;
 		rx_state = txerr <= rxerr ? state : 0;
 
-		if (likely(skb))
-			can_change_state(dev, cf, tx_state, rx_state);
-		else
-			priv->can.state = state;
+		/* The skb allocation might fail, but can_change_state()
+		 * handles cf == NULL.
+		 */
+		can_change_state(dev, cf, tx_state, rx_state);
 		if (state == CAN_STATE_BUS_OFF)
 			can_bus_off(dev);
 	}
 
-	if (likely(skb)) {
-		stats->rx_packets++;
-		stats->rx_bytes += cf->can_dlc;
+	if (likely(skb))
 		netif_rx(skb);
-	} else {
+	else
 		return -ENOMEM;
-	}
 
 	return 0;
 }
@@ -635,8 +657,8 @@ static irqreturn_t sun4i_can_interrupt(int irq, void *dev_id)
 	u8 isrc, status;
 	int n = 0;
 
-	while ((isrc = readl(priv->base + SUN4I_REG_INT_ADDR)) &&
-	       (n < SUN4I_CAN_MAX_IRQ)) {
+	while ((n < SUN4I_CAN_MAX_IRQ) &&
+	       (isrc = readl(priv->base + SUN4I_REG_INT_ADDR))) {
 		n++;
 		status = readl(priv->base + SUN4I_REG_STA_ADDR);
 
@@ -645,16 +667,13 @@ static irqreturn_t sun4i_can_interrupt(int irq, void *dev_id)
 
 		if (isrc & SUN4I_INT_TBUF_VLD) {
 			/* transmission complete interrupt */
-			stats->tx_bytes +=
-			    readl(priv->base +
-				  SUN4I_REG_RBUF_RBACK_START_ADDR) & 0xf;
+			stats->tx_bytes += can_get_echo_skb(dev, 0, NULL);
 			stats->tx_packets++;
-			can_get_echo_skb(dev, 0);
 			netif_wake_queue(dev);
-			can_led_event(dev, CAN_LED_EVENT_TX);
 		}
-		if (isrc & SUN4I_INT_RBUF_VLD) {
-			/* receive interrupt */
+		if ((isrc & SUN4I_INT_RBUF_VLD) &&
+		    !(isrc & SUN4I_INT_DATA_OR)) {
+			/* receive interrupt - don't read if overrun occurred */
 			while (status & SUN4I_STA_RBUF_RDY) {
 				/* RX buffer is not empty */
 				sun4i_can_rx(dev);
@@ -695,6 +714,13 @@ static int sun4ican_open(struct net_device *dev)
 		goto exit_irq;
 	}
 
+	/* software reset deassert */
+	err = reset_control_deassert(priv->reset);
+	if (err) {
+		netdev_err(dev, "could not deassert CAN reset\n");
+		goto exit_soft_reset;
+	}
+
 	/* turn on clocking for CAN peripheral block */
 	err = clk_prepare_enable(priv->clk);
 	if (err) {
@@ -708,7 +734,6 @@ static int sun4ican_open(struct net_device *dev)
 		goto exit_can_start;
 	}
 
-	can_led_event(dev, CAN_LED_EVENT_OPEN);
 	netif_start_queue(dev);
 
 	return 0;
@@ -716,6 +741,8 @@ static int sun4ican_open(struct net_device *dev)
 exit_can_start:
 	clk_disable_unprepare(priv->clk);
 exit_clock:
+	reset_control_assert(priv->reset);
+exit_soft_reset:
 	free_irq(dev->irq, dev);
 exit_irq:
 	close_candev(dev);
@@ -729,10 +756,10 @@ static int sun4ican_close(struct net_device *dev)
 	netif_stop_queue(dev);
 	sun4i_can_stop(dev);
 	clk_disable_unprepare(priv->clk);
+	reset_control_assert(priv->reset);
 
 	free_irq(dev->irq, dev);
 	close_candev(dev);
-	can_led_event(dev, CAN_LED_EVENT_STOP);
 
 	return 0;
 }
@@ -743,32 +770,79 @@ static const struct net_device_ops sun4ican_netdev_ops = {
 	.ndo_start_xmit = sun4ican_start_xmit,
 };
 
+static const struct ethtool_ops sun4ican_ethtool_ops = {
+	.get_ts_info = ethtool_op_get_ts_info,
+};
+
+static const struct sun4ican_quirks sun4ican_quirks_a10 = {
+	.has_reset = false,
+	.acp_offset = 0,
+};
+
+static const struct sun4ican_quirks sun4ican_quirks_r40 = {
+	.has_reset = true,
+	.acp_offset = 0,
+};
+
+static const struct sun4ican_quirks sun4ican_quirks_d1 = {
+	.has_reset = true,
+	.acp_offset = (SUN4I_REG_ACPC_ADDR_D1 - SUN4I_REG_ACPC_ADDR),
+};
+
 static const struct of_device_id sun4ican_of_match[] = {
-	{.compatible = "allwinner,sun4i-a10-can"},
-	{},
+	{
+		.compatible = "allwinner,sun4i-a10-can",
+		.data = &sun4ican_quirks_a10
+	}, {
+		.compatible = "allwinner,sun7i-a20-can",
+		.data = &sun4ican_quirks_a10
+	}, {
+		.compatible = "allwinner,sun8i-r40-can",
+		.data = &sun4ican_quirks_r40
+	}, {
+		.compatible = "allwinner,sun20i-d1-can",
+		.data = &sun4ican_quirks_d1
+	}, {
+		/* sentinel */
+	},
 };
 
 MODULE_DEVICE_TABLE(of, sun4ican_of_match);
 
-static int sun4ican_remove(struct platform_device *pdev)
+static void sun4ican_remove(struct platform_device *pdev)
 {
 	struct net_device *dev = platform_get_drvdata(pdev);
 
 	unregister_netdev(dev);
 	free_candev(dev);
-
-	return 0;
 }
 
 static int sun4ican_probe(struct platform_device *pdev)
 {
 	struct device_node *np = pdev->dev.of_node;
-	struct resource *mem;
 	struct clk *clk;
+	struct reset_control *reset = NULL;
 	void __iomem *addr;
 	int err, irq;
 	struct net_device *dev;
 	struct sun4ican_priv *priv;
+	const struct sun4ican_quirks *quirks;
+
+	quirks = of_device_get_match_data(&pdev->dev);
+	if (!quirks) {
+		dev_err(&pdev->dev, "failed to determine the quirks to use\n");
+		err = -ENODEV;
+		goto exit;
+	}
+
+	if (quirks->has_reset) {
+		reset = devm_reset_control_get_exclusive(&pdev->dev, NULL);
+		if (IS_ERR(reset)) {
+			dev_err(&pdev->dev, "unable to request reset\n");
+			err = PTR_ERR(reset);
+			goto exit;
+		}
+	}
 
 	clk = of_clk_get(np, 0);
 	if (IS_ERR(clk)) {
@@ -779,15 +853,13 @@ static int sun4ican_probe(struct platform_device *pdev)
 
 	irq = platform_get_irq(pdev, 0);
 	if (irq < 0) {
-		dev_err(&pdev->dev, "could not get a valid irq\n");
 		err = -ENODEV;
 		goto exit;
 	}
 
-	mem = platform_get_resource(pdev, IORESOURCE_MEM, 0);
-	addr = devm_ioremap_resource(&pdev->dev, mem);
+	addr = devm_platform_ioremap_resource(pdev, 0);
 	if (IS_ERR(addr)) {
-		err = -EBUSY;
+		err = PTR_ERR(addr);
 		goto exit;
 	}
 
@@ -800,6 +872,7 @@ static int sun4ican_probe(struct platform_device *pdev)
 	}
 
 	dev->netdev_ops = &sun4ican_netdev_ops;
+	dev->ethtool_ops = &sun4ican_ethtool_ops;
 	dev->irq = irq;
 	dev->flags |= IFF_ECHO;
 
@@ -811,10 +884,11 @@ static int sun4ican_probe(struct platform_device *pdev)
 	priv->can.ctrlmode_supported = CAN_CTRLMODE_BERR_REPORTING |
 				       CAN_CTRLMODE_LISTENONLY |
 				       CAN_CTRLMODE_LOOPBACK |
-				       CAN_CTRLMODE_PRESUME_ACK |
 				       CAN_CTRLMODE_3_SAMPLES;
 	priv->base = addr;
 	priv->clk = clk;
+	priv->reset = reset;
+	priv->acp_offset = quirks->acp_offset;
 	spin_lock_init(&priv->cmdreg_lock);
 
 	platform_set_drvdata(pdev, dev);
@@ -826,7 +900,6 @@ static int sun4ican_probe(struct platform_device *pdev)
 			DRV_NAME, err);
 		goto exit_free;
 	}
-	devm_can_led_init(dev);
 
 	dev_info(&pdev->dev, "device registered (base=%p, irq=%d)\n",
 		 priv->base, dev->irq);
@@ -853,4 +926,4 @@ module_platform_driver(sun4i_can_driver);
 MODULE_AUTHOR("Peter Chen <xingkongcp@gmail.com>");
 MODULE_AUTHOR("Gerhard Bertelsmann <info@gerhard-bertelsmann.de>");
 MODULE_LICENSE("Dual BSD/GPL");
-MODULE_DESCRIPTION("CAN driver for Allwinner SoCs (A10/A20)");
+MODULE_DESCRIPTION("CAN driver for Allwinner SoCs (A10/A20/D1)");