net: dsa: b53: Make SRAB driver manage port interrupts

Update the SRAB driver to manage per-port interrupts. Since we cannot
sleep during b53_io_ops, schedule a workqueue whenever we get a port
specific interrupt. We will later make use of this to call back into
PHYLINK when there is e.g: a link state change.

Signed-off-by: Florian Fainelli <f.fainelli@gmail.com>
Reviewed-by: Andrew Lunn <andrew@lunn.ch>
Signed-off-by: David S. Miller <davem@davemloft.net>

diff --git a/drivers/net/dsa/b53/b53_srab.c b/drivers/net/dsa/b53/b53_srab.c
index 91de2ba..645dde0 100644 (file)
--- a/drivers/net/dsa/b53/b53_srab.c
+++ b/drivers/net/dsa/b53/b53_srab.c
@@ -19,6 +19,7 @@
 #include <linux/kernel.h>
 #include <linux/module.h>
 #include <linux/delay.h>
+#include <linux/interrupt.h>
 #include <linux/platform_device.h>
 #include <linux/platform_data/b53.h>
 #include <linux/of.h>
@@ -47,6 +48,7 @@
 
 /* command and status register of the SRAB */
 #define B53_SRAB_CTRLS                 0x40
+#define  B53_SRAB_CTRLS_HOST_INTR      BIT(1)
 #define  B53_SRAB_CTRLS_RCAREQ         BIT(3)
 #define  B53_SRAB_CTRLS_RCAGNT         BIT(4)
 #define  B53_SRAB_CTRLS_SW_INIT_DONE   BIT(6)
@@ -60,8 +62,16 @@
 #define  B53_SRAB_P7_SLEEP_TIMER       BIT(11)
 #define  B53_SRAB_IMP0_SLEEP_TIMER     BIT(12)
 
+struct b53_srab_port_priv {
+       int irq;
+       bool irq_enabled;
+       struct b53_device *dev;
+       unsigned int num;
+};
+
 struct b53_srab_priv {
        void __iomem *regs;
+       struct b53_srab_port_priv port_intrs[B53_N_PORTS];
 };
 
 static int b53_srab_request_grant(struct b53_device *dev)
@@ -344,6 +354,49 @@ err:
        return ret;
 }
 
+static irqreturn_t b53_srab_port_thread(int irq, void *dev_id)
+{
+       return IRQ_HANDLED;
+}
+
+static irqreturn_t b53_srab_port_isr(int irq, void *dev_id)
+{
+       struct b53_srab_port_priv *port = dev_id;
+       struct b53_device *dev = port->dev;
+       struct b53_srab_priv *priv = dev->priv;
+
+       /* Acknowledge the interrupt */
+       writel(BIT(port->num), priv->regs + B53_SRAB_INTR);
+
+       return IRQ_WAKE_THREAD;
+}
+
+static int b53_srab_irq_enable(struct b53_device *dev, int port)
+{
+       struct b53_srab_priv *priv = dev->priv;
+       struct b53_srab_port_priv *p = &priv->port_intrs[port];
+       int ret;
+
+       ret = request_threaded_irq(p->irq, b53_srab_port_isr,
+                                  b53_srab_port_thread, 0,
+                                  dev_name(dev->dev), p);
+       if (!ret)
+               p->irq_enabled = true;
+
+       return ret;
+}
+
+static void b53_srab_irq_disable(struct b53_device *dev, int port)
+{
+       struct b53_srab_priv *priv = dev->priv;
+       struct b53_srab_port_priv *p = &priv->port_intrs[port];
+
+       if (p->irq_enabled) {
+               free_irq(p->irq, p);
+               p->irq_enabled = false;
+       }
+}
+
 static const struct b53_io_ops b53_srab_ops = {
        .read8 = b53_srab_read8,
        .read16 = b53_srab_read16,
@@ -355,6 +408,8 @@ static const struct b53_io_ops b53_srab_ops = {
        .write32 = b53_srab_write32,
        .write48 = b53_srab_write48,
        .write64 = b53_srab_write64,
+       .irq_enable = b53_srab_irq_enable,
+       .irq_disable = b53_srab_irq_disable,
 };
 
 static const struct of_device_id b53_srab_of_match[] = {
@@ -379,6 +434,52 @@ static const struct of_device_id b53_srab_of_match[] = {
 };
 MODULE_DEVICE_TABLE(of, b53_srab_of_match);
 
+static void b53_srab_intr_set(struct b53_srab_priv *priv, bool set)
+{
+       u32 reg;
+
+       reg = readl(priv->regs + B53_SRAB_CTRLS);
+       if (set)
+               reg |= B53_SRAB_CTRLS_HOST_INTR;
+       else
+               reg &= ~B53_SRAB_CTRLS_HOST_INTR;
+       writel(reg, priv->regs + B53_SRAB_CTRLS);
+}
+
+static void b53_srab_prepare_irq(struct platform_device *pdev)
+{
+       struct b53_device *dev = platform_get_drvdata(pdev);
+       struct b53_srab_priv *priv = dev->priv;
+       struct b53_srab_port_priv *port;
+       unsigned int i;
+       char *name;
+
+       /* Clear all pending interrupts */
+       writel(0xffffffff, priv->regs + B53_SRAB_INTR);
+
+       if (dev->pdata && dev->pdata->chip_id != BCM58XX_DEVICE_ID)
+               return;
+
+       for (i = 0; i < B53_N_PORTS; i++) {
+               port = &priv->port_intrs[i];
+
+               /* There is no port 6 */
+               if (i == 6)
+                       continue;
+
+               name = kasprintf(GFP_KERNEL, "link_state_p%d", i);
+               if (!name)
+                       return;
+
+               port->num = i;
+               port->dev = dev;
+               port->irq = platform_get_irq_byname(pdev, name);
+               kfree(name);
+       }
+
+       b53_srab_intr_set(priv, true);
+}
+
 static int b53_srab_probe(struct platform_device *pdev)
 {
        struct b53_platform_data *pdata = pdev->dev.platform_data;
@@ -417,13 +518,17 @@ static int b53_srab_probe(struct platform_device *pdev)
 
        platform_set_drvdata(pdev, dev);
 
+       b53_srab_prepare_irq(pdev);
+
        return b53_switch_register(dev);
 }
 
 static int b53_srab_remove(struct platform_device *pdev)
 {
        struct b53_device *dev = platform_get_drvdata(pdev);
+       struct b53_srab_priv *priv = dev->priv;
 
+       b53_srab_intr_set(priv, false);
        if (dev)
                b53_switch_remove(dev);