Hi,
On 11/22/2017 11:33 PM, Stephen Boyd wrote:
> On 11/21/2017 01:23 AM, Manu Gautam wrote:
>> PHY must be powered on before turning ON clocks and
>> attempting to initialize it. Driver is exposing
>> separate init and power_on routines for this.
>> Apparently USB dwc3 core driver performs power-on after
>> init. Also, poweron and init for QMP PHY need to be
> Why does dwc3 driver power on after init? Seems backwards.
There are not many PHY drivers implementing power_on, rather they
rely on init to take care of complete initialization. However though
the name indicates power_on, but PHY drivers are not using it to
turn on power supplies but rather PHY register operations to enable/
start PHY - somewhat like init only.
>
>> executed together always, hence remove poweron callback
>> from phy_ops and explicitly perform this from com_init,
> Why do they need to be executed together?
Hardware programming guide requires PHY supplies to be ON before
it is initialized. And if PHY supplies were turned-off, then it must
be reset after turning them ON.
>
>> similar changes needed for poweroff. On similar lines move
>> clk_enable from init to com_init which can be called once
>> for multi lane PHYs.
> Please add parenthesis, clk_enable() for example, to functions so we
> know they're functions.
Ok.
>
>> Signed-off-by: Manu Gautam <mgautam@xxxxxxxxxxxxxx>
>> ---
>> drivers/phy/qualcomm/phy-qcom-qmp.c | 61 +++++++++++++------------------------
>> 1 file changed, 21 insertions(+), 40 deletions(-)
>>
>> diff --git a/drivers/phy/qualcomm/phy-qcom-qmp.c b/drivers/phy/qualcomm/phy-qcom-qmp.c
>> index 90794dd..2f427e3 100644
>> --- a/drivers/phy/qualcomm/phy-qcom-qmp.c
>> +++ b/drivers/phy/qualcomm/phy-qcom-qmp.c
>> @@ -720,33 +720,6 @@ static void qcom_qmp_phy_configure(void __iomem *base,
>> }
>> }
>>
>> -static int qcom_qmp_phy_poweron(struct phy *phy)
>> -{
>> - struct qmp_phy *qphy = phy_get_drvdata(phy);
>> - struct qcom_qmp *qmp = qphy->qmp;
>> - int num = qmp->cfg->num_vregs;
>> - int ret;
>> -
>> - dev_vdbg(&phy->dev, "Powering on QMP phy\n");
>> -
>> - /* turn on regulator supplies */
>> - ret = regulator_bulk_enable(num, qmp->vregs);
>> - if (ret)
>> - dev_err(qmp->dev, "failed to enable regulators, err=%d\n", ret);
>> -
>> - return ret;
>> -}
>> -
>> -static int qcom_qmp_phy_poweroff(struct phy *phy)
>> -{
>> - struct qmp_phy *qphy = phy_get_drvdata(phy);
>> - struct qcom_qmp *qmp = qphy->qmp;
>> -
>> - regulator_bulk_disable(qmp->cfg->num_vregs, qmp->vregs);
>> -
>> - return 0;
>> -}
>> -
>> static int qcom_qmp_phy_com_init(struct qcom_qmp *qmp)
>> {
>> const struct qmp_phy_cfg *cfg = qmp->cfg;
>> @@ -759,6 +732,19 @@ static int qcom_qmp_phy_com_init(struct qcom_qmp *qmp)
>> return 0;
>> }
>>
>> + /* turn on regulator supplies */
>> + ret = regulator_bulk_enable(cfg->num_vregs, qmp->vregs);
>> + if (ret) {
>> + mutex_unlock(&qmp->phy_mutex);
>> + return ret;
> This could also be a goto.
Yes, I can replace with goto here.
>
>> + }
>> +
>> + ret = clk_bulk_prepare_enable(cfg->num_clks, qmp->clks);
>> + if (ret) {
>> + dev_err(qmp->dev, "failed to enable clks, err=%d\n", ret);
>> + goto err_clk_enable;
>> + }
>> +
>> for (i = 0; i < cfg->num_resets; i++) {
>> ret = reset_control_deassert(qmp->resets[i]);
>> if (ret) {
--
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