diff mbox series

spi: pl022: add a message state STATE_TIMEOUT for timeout transfer

Message ID 20190118033229.22553-1-jiwei.sun@windriver.com (mailing list archive)
State Accepted
Commit 7aef2b646b24247d880a353e09d4e10614a61cd6
Headers show
Series spi: pl022: add a message state STATE_TIMEOUT for timeout transfer | expand

Commit Message

Jiwei Sun Jan. 18, 2019, 3:32 a.m. UTC 
When transfer timeout, give -EAGAIN to the message's status, and it can
make the spi device driver choose repeated transimation or not. And if
transfer timeout, output some useful information for tracing the issue.

Signed-off-by: Jiwei Sun <jiwei.sun@windriver.com>
---
 drivers/spi/spi-pl022.c | 30 +++++++++++++++++++++++++++++-
 1 file changed, 29 insertions(+), 1 deletion(-)

Comments

Linus Walleij Jan. 21, 2019, 1:57 p.m. UTC | #1 
On Fri, Jan 18, 2019 at 4:33 AM Jiwei Sun <jiwei.sun@windriver.com> wrote:

> When transfer timeout, give -EAGAIN to the message's status, and it can
> make the spi device driver choose repeated transimation or not. And if
> transfer timeout, output some useful information for tracing the issue.
>
> Signed-off-by: Jiwei Sun <jiwei.sun@windriver.com>

This looks very good and helpful!

Reviewed-by: Linus Walleij <linus.walleij@linaro.org>

Yours,
Linus Walleij
diff mbox series

Patch

diff --git a/drivers/spi/spi-pl022.c b/drivers/spi/spi-pl022.c
index 0c793e31d60f..26684178786f 100644
--- a/drivers/spi/spi-pl022.c
+++ b/drivers/spi/spi-pl022.c
@@ -253,6 +253,7 @@ 
 #define STATE_RUNNING			((void *) 1)
 #define STATE_DONE			((void *) 2)
 #define STATE_ERROR			((void *) -1)
+#define STATE_TIMEOUT			((void *) -2)
 
 /*
  * SSP State - Whether Enabled or Disabled
@@ -1484,6 +1485,30 @@  static void do_interrupt_dma_transfer(struct pl022 *pl022)
 	writew(irqflags, SSP_IMSC(pl022->virtbase));
 }
 
+static void print_current_status(struct pl022 *pl022)
+{
+	u32 read_cr0;
+	u16 read_cr1, read_dmacr, read_sr;
+
+	if (pl022->vendor->extended_cr)
+		read_cr0 = readl(SSP_CR0(pl022->virtbase));
+	else
+		read_cr0 = readw(SSP_CR0(pl022->virtbase));
+	read_cr1 = readw(SSP_CR1(pl022->virtbase));
+	read_dmacr = readw(SSP_DMACR(pl022->virtbase));
+	read_sr = readw(SSP_SR(pl022->virtbase));
+
+	dev_warn(&pl022->adev->dev, "spi-pl022 CR0: %x\n", read_cr0);
+	dev_warn(&pl022->adev->dev, "spi-pl022 CR1: %x\n", read_cr1);
+	dev_warn(&pl022->adev->dev, "spi-pl022 DMACR: %x\n", read_dmacr);
+	dev_warn(&pl022->adev->dev, "spi-pl022 SR: %x\n", read_sr);
+	dev_warn(&pl022->adev->dev,
+			"spi-pl022 exp_fifo_level/fifodepth: %u/%d\n",
+			pl022->exp_fifo_level,
+			pl022->vendor->fifodepth);
+
+}
+
 static void do_polling_transfer(struct pl022 *pl022)
 {
 	struct spi_message *message = NULL;
@@ -1535,7 +1560,8 @@  static void do_polling_transfer(struct pl022 *pl022)
 			if (time_after(time, timeout)) {
 				dev_warn(&pl022->adev->dev,
 				"%s: timeout!\n", __func__);
-				message->state = STATE_ERROR;
+				message->state = STATE_TIMEOUT;
+				print_current_status(pl022);
 				goto out;
 			}
 			cpu_relax();
@@ -1553,6 +1579,8 @@  static void do_polling_transfer(struct pl022 *pl022)
 	/* Handle end of message */
 	if (message->state == STATE_DONE)
 		message->status = 0;
+	else if (message->state == STATE_TIMEOUT)
+		message->status = -EAGAIN;
 	else
 		message->status = -EIO;