From: Anders Berg <anders.b...@avagotech.com>
If the device tree does not specify an interrupt property, the device driver
falls back to polling the controller status. This is needed to support
simulator models without interrupt capabilities.
Signed-off-by: Anders Berg <anders.b...@avagotech.com>
---
drivers/i2c/busses/i2c-axxia.c | 71 ++++++++++++++++++++++++----------------
1 file changed, 42 insertions(+), 29 deletions(-)
diff --git a/drivers/i2c/busses/i2c-axxia.c b/drivers/i2c/busses/i2c-axxia.c
index 15d5f0d..6ea1593 100644
--- a/drivers/i2c/busses/i2c-axxia.c
+++ b/drivers/i2c/busses/i2c-axxia.c
@@ -332,21 +332,11 @@ status_str(u32 status)
return buf;
}
-static irqreturn_t
-axxia_i2c_isr(int irq, void *_dev)
+static void
+axxia_i2c_service_irq(struct axxia_i2c_dev *idev)
{
- struct axxia_i2c_dev *idev = _dev;
u32 status = readl(&idev->regs->mst_int_status);
- if ((readl(&idev->regs->interrupt_status) & 0x1) == 0)
- return IRQ_NONE;
-
- if (!idev->msg)
- return IRQ_NONE;
-
- /* Clear interrupt */
- writel(0x01, &idev->regs->interrupt_status);
-
/* RX FIFO needs service? */
if (i2c_m_rd(idev->msg) && (status & MST_STATUS_RFL))
axxia_i2c_empty_rx_fifo(idev);
@@ -381,6 +371,23 @@ axxia_i2c_isr(int irq, void *_dev)
readl(&idev->regs->mst_tx_xfer));
complete(&idev->msg_complete);
}
+}
+
+static irqreturn_t
+axxia_i2c_isr(int irq, void *_dev)
+{
+ struct axxia_i2c_dev *idev = _dev;
+
+ if ((readl(&idev->regs->interrupt_status) & 0x1) == 0)
+ return IRQ_NONE;
+
+ if (!idev->msg)
+ return IRQ_NONE;
+
+ axxia_i2c_service_irq(idev);
+
+ /* Clear interrupt */
+ writel(0x01, &idev->regs->interrupt_status);
return IRQ_HANDLED;
}
@@ -447,14 +454,21 @@ axxia_i2c_xfer_msg(struct axxia_i2c_dev *idev, struct
i2c_msg *msg)
/* Start manual mode */
writel(0x8, &idev->regs->mst_command);
- i2c_int_enable(idev, int_mask);
-
- ret = wait_for_completion_timeout(&idev->msg_complete,
- I2C_XFER_TIMEOUT);
-
- i2c_int_disable(idev, int_mask);
+ if (idev->irq > 0) {
+ i2c_int_enable(idev, int_mask);
+ ret = wait_for_completion_timeout(&idev->msg_complete,
+ I2C_XFER_TIMEOUT);
+ i2c_int_disable(idev, int_mask);
+ WARN_ON(readl(&idev->regs->mst_command) & 0x8);
+ } else {
+ unsigned long tmo = jiffies + I2C_XFER_TIMEOUT;
- WARN_ON(readl(&idev->regs->mst_command) & 0x8);
+ do {
+ /* Poll interrupt status */
+ axxia_i2c_service_irq(idev);
+ ret = try_wait_for_completion(&idev->msg_complete);
+ } while (!ret && time_before(jiffies, tmo));
+ }
if (ret == 0) {
dev_warn(idev->dev, "xfer timeout (%#x)\n", msg->addr);
@@ -546,11 +560,8 @@ axxia_i2c_probe(struct platform_device *pdev)
}
irq = irq_of_parse_and_map(np, 0);
- if (irq == 0) {
- dev_err(&pdev->dev, "no irq property\n");
- ret = -EINVAL;
- goto err_cleanup;
- }
+ if (irq == 0)
+ dev_info(&pdev->dev, "No IRQ specified, using polling mode\n");
i2c_clk = clk_get(&pdev->dev, "i2c");
if (IS_ERR(i2c_clk)) {
@@ -589,12 +600,14 @@ axxia_i2c_probe(struct platform_device *pdev)
goto err_cleanup;
}
- ret = request_irq(irq, axxia_i2c_isr, 0, pdev->name, idev);
- if (ret) {
- dev_err(&pdev->dev, "Failed to request irq %i\n", idev->irq);
- goto err_cleanup;
+ if (irq) {
+ ret = request_irq(irq, axxia_i2c_isr, 0, pdev->name, idev);
+ if (ret) {
+ dev_err(&pdev->dev, "Failed to request irq %i\n", irq);
+ goto err_cleanup;
+ }
+ idev->irq = irq;
}
- idev->irq = irq;
clk_enable(idev->i2c_clk);
--
1.7.9.5
--
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