diff mbox series

[v3] usb: misc: ljca: Fix enumeration error on Dell Latitude 9420

Message ID 20231121203205.223047-1-hdegoede@redhat.com (mailing list archive)
State Accepted
Commit 372ee6a3368ec6ff46ee4e6ff4ffe2fe1e059dbb
Headers show
Series [v3] usb: misc: ljca: Fix enumeration error on Dell Latitude 9420 | expand

Commit Message

Hans de Goede Nov. 21, 2023, 8:32 p.m. UTC
Not all LJCA chips implement SPI and on chips without SPI reading
the SPI descriptors will timeout.

On laptop models like the Dell Latitude 9420, this is expected behavior
and not an error.

Modify the driver to continue without instantiating a SPI auxbus child,
instead of failing to probe() the whole LJCA chip.

Fixes: acd6199f195d ("usb: Add support for Intel LJCA device")
Cc: stable@vger.kernel.org
Signed-off-by: Hans de Goede <hdegoede@redhat.com>
Reviewed-by: Wentong Wu <wentong.wu@intel.com>
Link: https://lore.kernel.org/r/20231104175104.38786-1-hdegoede@redhat.com
---
Changes in v3:
- Fix commit-id in fixes tag

Changes in v2:
- Small commit msg + comment fixes
- Add Fixes tag + Cc: stable
---
 drivers/usb/misc/usb-ljca.c | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

Comments

Greg KH Nov. 22, 2023, 12:11 p.m. UTC | #1
On Tue, Nov 21, 2023 at 09:32:05PM +0100, Hans de Goede wrote:
> Not all LJCA chips implement SPI and on chips without SPI reading
> the SPI descriptors will timeout.
> 
> On laptop models like the Dell Latitude 9420, this is expected behavior
> and not an error.
> 
> Modify the driver to continue without instantiating a SPI auxbus child,
> instead of failing to probe() the whole LJCA chip.
> 
> Fixes: acd6199f195d ("usb: Add support for Intel LJCA device")
> Cc: stable@vger.kernel.org

Nit, stable is not needed as the above commit only ended up in 6.7-rc1,
nothing older.  I'll drop it when I queue this up, thanks!

greg k-h
Andi Shyti Nov. 22, 2023, 9:40 p.m. UTC | #2
Hi Hans,

On Tue, Nov 21, 2023 at 09:32:05PM +0100, Hans de Goede wrote:
> Not all LJCA chips implement SPI and on chips without SPI reading
> the SPI descriptors will timeout.
> 
> On laptop models like the Dell Latitude 9420, this is expected behavior
> and not an error.
> 
> Modify the driver to continue without instantiating a SPI auxbus child,
> instead of failing to probe() the whole LJCA chip.
> 
> Fixes: acd6199f195d ("usb: Add support for Intel LJCA device")
> Cc: stable@vger.kernel.org

did this already make it to stable? I think it is not needed.

> Signed-off-by: Hans de Goede <hdegoede@redhat.com>
> Reviewed-by: Wentong Wu <wentong.wu@intel.com>
> Link: https://lore.kernel.org/r/20231104175104.38786-1-hdegoede@redhat.com

Reviewed-by: Andi Shyti <andi.shyti@linux.intel.com>

Thanks,
Andi

> ---
> Changes in v3:
> - Fix commit-id in fixes tag
> 
> Changes in v2:
> - Small commit msg + comment fixes
> - Add Fixes tag + Cc: stable
> ---
>  drivers/usb/misc/usb-ljca.c | 3 ++-
>  1 file changed, 2 insertions(+), 1 deletion(-)
> 
> diff --git a/drivers/usb/misc/usb-ljca.c b/drivers/usb/misc/usb-ljca.c
> index c9decd0396d4..a280d3a54b18 100644
> --- a/drivers/usb/misc/usb-ljca.c
> +++ b/drivers/usb/misc/usb-ljca.c
> @@ -656,10 +656,11 @@ static int ljca_enumerate_spi(struct ljca_adapter *adap)
>  	unsigned int i;
>  	int ret;
>  
> +	/* Not all LJCA chips implement SPI, a timeout reading the descriptors is normal */
>  	ret = ljca_send(adap, LJCA_CLIENT_MNG, LJCA_MNG_ENUM_SPI, NULL, 0, buf,
>  			sizeof(buf), true, LJCA_ENUM_CLIENT_TIMEOUT_MS);
>  	if (ret < 0)
> -		return ret;
> +		return (ret == -ETIMEDOUT) ? 0 : ret;
>  
>  	/* check firmware response */
>  	desc = (struct ljca_spi_descriptor *)buf;
> -- 
> 2.41.0
diff mbox series

Patch

diff --git a/drivers/usb/misc/usb-ljca.c b/drivers/usb/misc/usb-ljca.c
index c9decd0396d4..a280d3a54b18 100644
--- a/drivers/usb/misc/usb-ljca.c
+++ b/drivers/usb/misc/usb-ljca.c
@@ -656,10 +656,11 @@  static int ljca_enumerate_spi(struct ljca_adapter *adap)
 	unsigned int i;
 	int ret;
 
+	/* Not all LJCA chips implement SPI, a timeout reading the descriptors is normal */
 	ret = ljca_send(adap, LJCA_CLIENT_MNG, LJCA_MNG_ENUM_SPI, NULL, 0, buf,
 			sizeof(buf), true, LJCA_ENUM_CLIENT_TIMEOUT_MS);
 	if (ret < 0)
-		return ret;
+		return (ret == -ETIMEDOUT) ? 0 : ret;
 
 	/* check firmware response */
 	desc = (struct ljca_spi_descriptor *)buf;