[PATCH] Input: cyttsp - Verbose error on soft reset

The first thing the Cypress driver does when starting
up is to try a soft reset. This is the first point where
the driver SPI/I2C communication can fail, so put out some
nice debug text:

  cyttsp-spi spi2.0: failed to send soft reset

Instead of just:

  cyttsp-spi: probe of spi2.0 failed with error -5

This is more helpful.

Cc: Ferruh Yigit <redacted>
Signed-off-by: Linus Walleij <redacted>
---
 drivers/input/touchscreen/cyttsp_core.c | 6 +++++-
 1 file changed, 5 insertions(+), 1 deletion(-)

diff --git a/drivers/input/touchscreen/cyttsp_core.c b/drivers/input/touchscreen/cyttsp_core.c
index 73c854f35f33..b9772192b5ea 100644
--- a/drivers/input/touchscreen/cyttsp_core.c
+++ b/drivers/input/touchscreen/cyttsp_core.c

@@ -248,12 +248,16 @@ static int cyttsp_soft_reset(struct cyttsp *ts)
 	enable_irq(ts->irq);
 
 	retval = ttsp_send_command(ts, CY_SOFT_RESET_MODE);
-	if (retval)
+	if (retval) {
+		dev_err(ts->dev, "failed to send soft reset\n");
 		goto out;
+	}
 
 	timeout = wait_for_completion_timeout(&ts->bl_ready,
 			msecs_to_jiffies(CY_DELAY_DFLT * CY_DELAY_MAX));
 	retval = timeout ? 0 : -EIO;
+	if (retval)
+		dev_err(ts->dev, "timeout waiting for soft reset\n");
 
 out:
 	ts->state = CY_IDLE_STATE;

-- 
2.29.2

Hi Linus,

On Mon, Mar 22, 2021 at 11:13:49PM +0100, Linus Walleij wrote:

I think if we have conditional for the error message then having ternary
above does not make sense. I changed this to:

	if (!wait_for_completion_timeout(&ts->bl_ready,
			msecs_to_jiffies(CY_DELAY_DFLT * CY_DELAY_MAX))) {
		dev_err(ts->dev, "timeout waiting for soft reset\n");
		retval = -EIO;
	}

Thanks.

-- 
Dmitry

On Tue, Mar 23, 2021 at 4:57 AM Dmitry Torokhov
[off-list ref] wrote:

On Mon, Mar 22, 2021 at 11:13:49PM +0100, Linus Walleij wrote:

quoted

      retval = timeout ? 0 : -EIO;
+     if (retval)
+             dev_err(ts->dev, "timeout waiting for soft reset\n");

I think if we have conditional for the error message then having ternary
above does not make sense. I changed this to:

Ah nice.

I'm starting to get this driver to work on a machine, so I hope I
will be able to make a few more serious improvements.

Yours,
Linus Walleij