| Message ID | a5cb5976-1ff3-de5f-14f6-18e6e00a61d5@xs4all.nl (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
On Tue, Dec 12, 2017 at 03:37:21PM +0100, Hans Verkuil wrote: > Hi Russell, > > On 08/12/17 12:59, Russell King - ARM Linux wrote: > > On Wed, Dec 06, 2017 at 02:54:04PM +0100, Hans Verkuil wrote: > >> On 12/06/17 13:35, Russell King wrote: > >>> We no longer use the CEC client to access the CEC part itself, so we can > >>> move this later in the initialisation sequence. > >>> > >>> Signed-off-by: Russell King <rmk+kernel@armlinux.org.uk> > >>> --- > >>> drivers/gpu/drm/i2c/tda998x_drv.c | 7 ++++--- > >>> 1 file changed, 4 insertions(+), 3 deletions(-) > >>> > >>> diff --git a/drivers/gpu/drm/i2c/tda998x_drv.c b/drivers/gpu/drm/i2c/tda998x_drv.c > >>> index 7f4dbca7f7f4..4aeac2127974 100644 > >>> --- a/drivers/gpu/drm/i2c/tda998x_drv.c > >>> +++ b/drivers/gpu/drm/i2c/tda998x_drv.c > >>> @@ -1490,9 +1490,6 @@ static int tda998x_create(struct i2c_client *client, struct tda998x_priv *priv) > >>> priv->cec_addr = 0x34 + (client->addr & 0x03); > >>> priv->current_page = 0xff; > >>> priv->hdmi = client; > >>> - priv->cec = i2c_new_dummy(client->adapter, priv->cec_addr); > >>> - if (!priv->cec) > >>> - return -ENODEV; > >>> > >>> /* wake up the device: */ > >>> cec_write(priv, REG_CEC_ENAMODS, > >>> @@ -1546,6 +1543,10 @@ static int tda998x_create(struct i2c_client *client, struct tda998x_priv *priv) > >>> CEC_FRO_IM_CLK_CTRL_GHOST_DIS | CEC_FRO_IM_CLK_CTRL_IMCLK_SEL); > >>> > >>> /* initialize the optional IRQ */ > >>> + priv->cec = i2c_new_dummy(client->adapter, priv->cec_addr); > >>> + if (!priv->cec) > >>> + return -ENODEV; > >>> + > >> > >> I'd move this up to before the 'initialize the optional IRQ' comment, since > >> that should stay with the 'if (client->irq) {' line below. > > > > I've swapped the order of patches 2 and 3, and moved this further down > > near where we add the real cec device in a later patch. This is > > starting to get quite different from the patch series that I've tested, > > and as I've already mentioned, testing is not going to happen for a > > while. > > > > I added support for this to am335x-boneblack-common.dtsi (see patch below), but > it doesn't work. I suspect the calibration since I see these messages: > > gpio-57 (nxp,calib): gpiod_direction_output: tried to set a GPIO tied to an IRQ as output It's annoying that different gpiochips have different behaviours, it means you can't develop a driver using gpios and know that it'll work elsewhere. It would be nice if everywhere behaved the same so that could've been detected earlier. > Which makes sense. I had a similar case in my cec-gpio driver and I had to completely > free the interrupt before I could set the direction to output. > > I do get nice interrupts when a transmit is done, so the interrupt works correctly. > And it correctly detects Ack/Nack. > > I looked a bit closer and I see that even without calibration the timings are reasonably > OK: 2.3 ms for a bit period instead of the recommended 2.4 ms. Slightly off but within > margins. > > But receiving messages fails: I get no interrupt at all. Not sure if the lack of > calibration is the cause of that, or if it is something else. I can take another look > once the calibration is fixed. Unfortuantely NXP don't document what the allowable tolerances are for the chip. I'd suggest getting the calibration working correctly would be a good first step.
diff --git a/arch/arm/boot/dts/am335x-boneblack-common.dtsi b/arch/arm/boot/dts/am335x-boneblack-common.dtsi index 325daae40278..07e6b36d17c4 100644 --- a/arch/arm/boot/dts/am335x-boneblack-common.dtsi +++ b/arch/arm/boot/dts/am335x-boneblack-common.dtsi @@ -7,6 +7,7 @@ */ #include <dt-bindings/display/tda998x.h> +#include <dt-bindings/interrupt-controller/irq.h> &ldo3_reg { regulator-min-microvolt = <1800000>; @@ -91,6 +92,8 @@ tda19988: tda19988 { compatible = "nxp,tda998x"; reg = <0x70>; + nxp,calib-gpios = <&gpio1 25 0>; + interrupts-extended = <&gpio1 25 IRQ_TYPE_LEVEL_LOW>; pinctrl-names = "default", "off"; pinctrl-0 = <&nxp_hdmi_bonelt_pins>;