[PATCH v2 2/2] drm: bridge: Move HPD handling to PHY operations
Neil Armstrong
narmstrong at baylibre.com
Fri Mar 3 09:07:11 UTC 2017
On 03/02/2017 05:18 PM, Laurent Pinchart wrote:
> Hi Neil,
>
> Thank you for the patch.
>
> On Thursday 02 Mar 2017 16:29:32 Neil Armstrong wrote:
>> The HDMI TX controller support HPD and RXSENSE signaling from the PHY
>> via it's STAT0 PHY interface, but some vendor PHYs can manage these
>> signals independently from the controller, thus these STAT0 handling
>> should be moved to PHY specific operations and become optional.
>>
>> The existing STAT0 HPD and RXSENSE handling code is refactored into
>> a supplementaty set of default PHY operations that are used automatically
>> when the platform glue doesn't provide its own operations.
>>
>> Signed-off-by: Neil Armstrong <narmstrong at baylibre.com>
>> ---
>> drivers/gpu/drm/bridge/dw-hdmi.c | 134 +++++++++++++++++++++++++-----------
>> include/drm/bridge/dw_hdmi.h | 8 +++
>> 2 files changed, 104 insertions(+), 38 deletions(-)
>>
>> diff --git a/drivers/gpu/drm/bridge/dw-hdmi.c
>> b/drivers/gpu/drm/bridge/dw-hdmi.c index 653ecd7..58dcf7d 100644
>> --- a/drivers/gpu/drm/bridge/dw-hdmi.c
>> +++ b/drivers/gpu/drm/bridge/dw-hdmi.c
>> @@ -1098,10 +1098,50 @@ static enum drm_connector_status
>> dw_hdmi_phy_read_hpd(struct dw_hdmi *hdmi, connector_status_connected :
>> connector_status_disconnected;
>> }
>>
>> +static void dw_hdmi_phy_update_hpd(struct dw_hdmi *hdmi, void *data,
>> + bool force, bool disabled, bool rxsense)
>> +{
>> + if (force || disabled || !rxsense)
>> + hdmi->phy_mask |= HDMI_PHY_RX_SENSE;
>> + else
>> + hdmi->phy_mask &= ~HDMI_PHY_RX_SENSE;
>> +}
>> +
>> +static void dw_hdmi_phy_setup_hpd(struct dw_hdmi *hdmi, void *data)
>> +{
>> + /* setup HPD and RXSENSE interrupt polarity */
>> + hdmi_writeb(hdmi, HDMI_PHY_HPD | HDMI_PHY_RX_SENSE, HDMI_PHY_POL0);
>> +}
>> +
>> +static void dw_hdmi_phy_configure_hpd(struct dw_hdmi *hdmi, void *data)
>> +{
>> + /* enable cable hot plug irq */
>> + hdmi_writeb(hdmi, hdmi->phy_mask, HDMI_PHY_MASK0);
>> +}
>> +
>> +static void dw_hdmi_phy_clear_hpd(struct dw_hdmi *hdmi, void *data)
>> +{
>> + /* Clear Hotplug interrupts */
>> + hdmi_writeb(hdmi, HDMI_IH_PHY_STAT0_HPD | HDMI_IH_PHY_STAT0_RX_SENSE,
>> + HDMI_IH_PHY_STAT0);
>> +}
>> +
>> +static void dw_hdmi_phy_unmute_hpd(struct dw_hdmi *hdmi, void *data)
>> +{
>> + /* Unmute Hotplug interrupts */
>> + hdmi_writeb(hdmi, ~(HDMI_IH_PHY_STAT0_HPD |
> HDMI_IH_PHY_STAT0_RX_SENSE),
>> + HDMI_IH_MUTE_PHY_STAT0);
>> +}
>
> Do we really need all those new operations ? It looks to me like a bit of
> refactoring could help lowering the number of operations. We essentially need
>
> - an init function called at probe time (or likely rather at runtime PM resume
> time when we'll implement runtime PM)
>
> - an interrupt enable/disable function roughly equivalent to
> dw_hdmi_update_phy_mask()
>
> - a read function to report the detection results called from
> dw_hdmi_connector_detect()
Well, I strictly copied the 5 different operations involved in the HPD handling,
if you reduce to these 3 it will change the functional behavior of the driver regarding HPD/RxSenSe...
I do not have enough documentation and HW to actually experiment these changes !
For Amlogic I need setup, read, configure and clear. Only the unmute is specific to Synopsys PHY.
>
>> static const struct dw_hdmi_phy_ops dw_hdmi_synopsys_phy_ops = {
>> .init = dw_hdmi_phy_init,
>> .disable = dw_hdmi_phy_disable,
>> .read_hpd = dw_hdmi_phy_read_hpd,
>> + .update_hpd = dw_hdmi_phy_update_hpd,
>> + .setup_hpd = dw_hdmi_phy_setup_hpd,
>> + .configure_hpd = dw_hdmi_phy_configure_hpd,
>> + .clear_hpd = dw_hdmi_phy_clear_hpd,
>> + .unmute_hpd = dw_hdmi_phy_unmute_hpd,
>> };
>>
>> /* ------------------------------------------------------------------------
>> @@ -1507,11 +1547,12 @@ static int dw_hdmi_fb_registered(struct dw_hdmi
>> *hdmi) HDMI_PHY_I2CM_CTLINT_ADDR);
>>
>> /* enable cable hot plug irq */
>> - hdmi_writeb(hdmi, hdmi->phy_mask, HDMI_PHY_MASK0);
>> + if (hdmi->phy.ops->configure_hpd)
>> + hdmi->phy.ops->configure_hpd(hdmi, hdmi->phy.data);
>>
>> /* Clear Hotplug interrupts */
>> - hdmi_writeb(hdmi, HDMI_IH_PHY_STAT0_HPD | HDMI_IH_PHY_STAT0_RX_SENSE,
>> - HDMI_IH_PHY_STAT0);
>> + if (hdmi->phy.ops->clear_hpd)
>> + hdmi->phy.ops->clear_hpd(hdmi, hdmi->phy.data);
>
> The probe function contains the same code. Let's inline this function into
> probe, group all HPD-related initialization together and extract that into a
> function to keep probe easy to read. I think you can do that in a separate
> patch.
>
>> return 0;
>> }
>> @@ -1622,13 +1663,14 @@ static void dw_hdmi_update_phy_mask(struct dw_hdmi
>> *hdmi) {
>> u8 old_mask = hdmi->phy_mask;
>>
>> - if (hdmi->force || hdmi->disabled || !hdmi->rxsense)
>> - hdmi->phy_mask |= HDMI_PHY_RX_SENSE;
>> - else
>> - hdmi->phy_mask &= ~HDMI_PHY_RX_SENSE;
>> + if (hdmi->phy.ops->update_hpd)
>> + hdmi->phy.ops->update_hpd(hdmi, hdmi->phy.data,
>> + hdmi->force, hdmi->disabled,
>> + hdmi->rxsense);
>>
>> - if (old_mask != hdmi->phy_mask)
>> - hdmi_writeb(hdmi, hdmi->phy_mask, HDMI_PHY_MASK0);
>> + if (old_mask != hdmi->phy_mask &&
>
> phy_mask isn't accessible to glue code, so this test will never be true with
> vendor PHYs.
The problem is that the HPD/RxSense is tied to this phy_mask and glued into the
dw-hdmi driver.
The *real* solution would be to completely separate the HPD/RxSense irq handling to
a separate driver as a shared irq...
If Jose is willing to give me some documentation and Freescale some boards, I'll be
happy to do it !
>
>> + hdmi->phy.ops->configure_hpd)
>> + hdmi->phy.ops->configure_hpd(hdmi, hdmi->phy.data);
>> }
>>
>> static enum drm_connector_status
>> @@ -1820,6 +1862,41 @@ static irqreturn_t dw_hdmi_hardirq(int irq, void
>> *dev_id) return ret;
>> }
>>
>> +void __dw_hdmi_setup_rx_sense(struct dw_hdmi *hdmi, bool hpd, bool
>> rx_sense)
>> +{
>> + mutex_lock(&hdmi->mutex);
>> +
>> + if (!hdmi->disabled && !hdmi->force) {
>> + /*
>> + * If the RX sense status indicates we're disconnected,
>> + * clear the software rxsense status.
>> + */
>> + if (!rx_sense)
>> + hdmi->rxsense = false;
>> +
>> + /*
>> + * Only set the software rxsense status when both
>> + * rxsense and hpd indicates we're connected.
>> + * This avoids what seems to be bad behaviour in
>> + * at least iMX6S versions of the phy.
>> + */
>> + if (hpd)
>> + hdmi->rxsense = true;
>
> This contradicts the above comment, hdmi->rxsense is set back to true solely
> based on the hpd parameter.
The "hpd" here is an HPD event indicator, not the HPD pin status, so it makes sense.
I suppose the HPD and RxSense events don't come at the same time, but RxSense comes later on.
>> +
>> + dw_hdmi_update_power(hdmi);
>> + dw_hdmi_update_phy_mask(hdmi);
>> + }
>
> I'd add a blank line here.
Ok
>
>> + mutex_unlock(&hdmi->mutex);
>> +}
>> +
>> +void dw_hdmi_setup_rx_sense(struct device *dev, bool hpd, bool rx_sense)
>> +{
>> + struct dw_hdmi *hdmi = dev_get_drvdata(dev);
>> +
>> + __dw_hdmi_setup_rx_sense(hdmi, hpd, rx_sense);
>> +}
>> +EXPORT_SYMBOL_GPL(dw_hdmi_setup_rx_sense);
>> +
>> static irqreturn_t dw_hdmi_irq(int irq, void *dev_id)
>> {
>> struct dw_hdmi *hdmi = dev_id;
>> @@ -1852,30 +1929,10 @@ static irqreturn_t dw_hdmi_irq(int irq, void
>> *dev_id) * ask the source to re-read the EDID.
>> */
>> if (intr_stat &
>> - (HDMI_IH_PHY_STAT0_RX_SENSE | HDMI_IH_PHY_STAT0_HPD)) {
>> - mutex_lock(&hdmi->mutex);
>> - if (!hdmi->disabled && !hdmi->force) {
>> - /*
>> - * If the RX sense status indicates we're
> disconnected,
>> - * clear the software rxsense status.
>> - */
>> - if (!(phy_stat & HDMI_PHY_RX_SENSE))
>> - hdmi->rxsense = false;
>> -
>> - /*
>> - * Only set the software rxsense status when both
>> - * rxsense and hpd indicates we're connected.
>> - * This avoids what seems to be bad behaviour in
>> - * at least iMX6S versions of the phy.
>> - */
>> - if (phy_stat & HDMI_PHY_HPD)
>> - hdmi->rxsense = true;
>> -
>> - dw_hdmi_update_power(hdmi);
>> - dw_hdmi_update_phy_mask(hdmi);
>> - }
>> - mutex_unlock(&hdmi->mutex);
>> - }
>> + (HDMI_IH_PHY_STAT0_RX_SENSE | HDMI_IH_PHY_STAT0_HPD))
>
> Is this right ? If your SoC implements a custom HPD mechanism, does it still
> rely on the standard RX SENSE and HPD interrupts ? In particular, this
> function still writes the HDMI_IH_MUTE_PHY_STAT0 register directly, while
> you've extracted a write to the same register in the probe function into a PHY
> operation.
It won't since the IRQ is left masked and muted, and I moved all the HDMI_IH_*_PHY
into HPD ops.
>
>> + __dw_hdmi_setup_rx_sense(hdmi,
>> + phy_stat & HDMI_PHY_HPD,
>> + phy_stat & HDMI_PHY_RX_SENSE);
>>
>> if (intr_stat & HDMI_IH_PHY_STAT0_HPD) {
>> dev_dbg(hdmi->dev, "EVENT=%s\n",
>> @@ -2146,11 +2203,12 @@ static int dw_hdmi_detect_phy(struct dw_hdmi *hdmi)
>> * Configure registers related to HDMI interrupt
>> * generation before registering IRQ.
>> */
>> - hdmi_writeb(hdmi, HDMI_PHY_HPD | HDMI_PHY_RX_SENSE, HDMI_PHY_POL0);
>> + if (hdmi->phy.ops->setup_hpd)
>> + hdmi->phy.ops->setup_hpd(hdmi, hdmi->phy.data);
>>
>> /* Clear Hotplug interrupts */
>> - hdmi_writeb(hdmi, HDMI_IH_PHY_STAT0_HPD | HDMI_IH_PHY_STAT0_RX_SENSE,
>> - HDMI_IH_PHY_STAT0);
>> + if (hdmi->phy.ops->clear_hpd)
>> + hdmi->phy.ops->clear_hpd(hdmi, hdmi->phy.data);
>>
>> hdmi->bridge.driver_private = hdmi;
>> hdmi->bridge.funcs = &dw_hdmi_bridge_funcs;
>> @@ -2163,8 +2221,8 @@ static int dw_hdmi_detect_phy(struct dw_hdmi *hdmi)
>> goto err_iahb;
>>
>> /* Unmute interrupts */
>> - hdmi_writeb(hdmi, ~(HDMI_IH_PHY_STAT0_HPD |
> HDMI_IH_PHY_STAT0_RX_SENSE),
>> - HDMI_IH_MUTE_PHY_STAT0);
>> + if (hdmi->phy.ops->unmute_hpd)
>> + hdmi->phy.ops->unmute_hpd(hdmi, hdmi->phy.data);
>>
>> memset(&pdevinfo, 0, sizeof(pdevinfo));
>> pdevinfo.parent = dev;
>> diff --git a/include/drm/bridge/dw_hdmi.h b/include/drm/bridge/dw_hdmi.h
>> index 8c0cc13..d72403f 100644
>> --- a/include/drm/bridge/dw_hdmi.h
>> +++ b/include/drm/bridge/dw_hdmi.h
>> @@ -64,6 +64,12 @@ struct dw_hdmi_phy_ops {
>> struct drm_display_mode *mode);
>> void (*disable)(struct dw_hdmi *hdmi, void *data);
>> enum drm_connector_status (*read_hpd)(struct dw_hdmi *hdmi, void
> *data);
>> + void (*update_hpd)(struct dw_hdmi *hdmi, void *data,
>> + bool force, bool disabled, bool rxsense);
>> + void (*setup_hpd)(struct dw_hdmi *hdmi, void *data);
>> + void (*configure_hpd)(struct dw_hdmi *hdmi, void *data);
>> + void (*clear_hpd)(struct dw_hdmi *hdmi, void *data);
>> + void (*unmute_hpd)(struct dw_hdmi *hdmi, void *data);
>
> That's quite a lot of new operations. I think we need documentation :-)
We need documentation on all the other ops too !
Wehat would be the recommended format ?
>
>> };
>>
>> struct dw_hdmi_plat_data {
>> @@ -93,6 +99,8 @@ int dw_hdmi_probe(struct platform_device *pdev,
>> int dw_hdmi_bind(struct platform_device *pdev, struct drm_encoder *encoder,
>> const struct dw_hdmi_plat_data *plat_data);
>>
>> +void dw_hdmi_setup_rx_sense(struct device *dev, bool hpd, bool rx_sense);
>> +
>> void dw_hdmi_set_sample_rate(struct dw_hdmi *hdmi, unsigned int rate);
>> void dw_hdmi_audio_enable(struct dw_hdmi *hdmi);
>> void dw_hdmi_audio_disable(struct dw_hdmi *hdmi);
>
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