Hi,
Felipe Balbi <felipe.balbi@xxxxxxxxxxxxxxx> writes:
> Felipe Balbi <felipe.balbi@xxxxxxxxxxxxxxx> writes:
>> Synopsys Databook 2.60a has a note that if we're
>> sending a Start Transfer command we _must_ make sure
>> that DWC3_GUSB2PHY(n).SUSPHY bit is cleared.
>>
>> This patch implements that particular detail.
>>
>> Signed-off-by: Felipe Balbi <felipe.balbi@xxxxxxxxxxxxxxx>
>> ---
>> drivers/usb/dwc3/gadget.c | 25 +++++++++++++++++++++++++
>> 1 file changed, 25 insertions(+)
>>
>> diff --git a/drivers/usb/dwc3/gadget.c b/drivers/usb/dwc3/gadget.c
>> index 0967b5d8fb75..8b3a676db346 100644
>> --- a/drivers/usb/dwc3/gadget.c
>> +++ b/drivers/usb/dwc3/gadget.c
>> @@ -227,10 +227,29 @@ int dwc3_send_gadget_ep_cmd(struct dwc3 *dwc, unsigned ep,
>> struct dwc3_ep *dep = dwc->eps[ep];
>> u32 timeout = 500;
>> u32 reg;
>> +
>> + int susphy = false;
>> int ret = -EINVAL;
>>
>> trace_dwc3_gadget_ep_cmd(dep, cmd, params);
>>
>> + /*
>> + * Synopsys Databook 2.60a states, on section 6.3.2.5.5, that if we're
>> + * issuing a Start Transfer command, we must check if GUSB2PHYCFG.SUSPHY
>> + * bit is set. If it is, then we need to clear it.
>> + *
>> + * We will also set SUSPHY bit to what it was before returning as stated
>> + * by the same section on Synopsys databook.
>> + */
>> + if (cmd == DWC3_DEPCMD_STARTTRANSFER) {
>
> After digging a little deeper, every command needs this, not only Start
> Transfer. I'll remove this check.
Here's v2, I've pushed it to testing/next:
8<----------------------------------------------------------------
From 81b72307545522bb962f2ebbb49be8fef1ffa547 Mon Sep 17 00:00:00 2001
From: Felipe Balbi <felipe.balbi@xxxxxxxxxxxxxxx>
Date: Mon, 4 Apr 2016 09:19:17 +0300
Subject: [PATCH v2] usb: dwc3: gadget: clear SUSPHY bit before ep cmds
Synopsys Databook 2.60a has a note that if we're
sending an endpoint command we _must_ make sure that
DWC3_GUSB2PHY(n).SUSPHY bit is cleared.
This patch implements that particular detail.
Signed-off-by: Felipe Balbi <felipe.balbi@xxxxxxxxxxxxxxx>
---
changes since v1:
- clear SUSPHY for all endpoint commands
drivers/usb/dwc3/gadget.c | 23 +++++++++++++++++++++++
1 file changed, 23 insertions(+)
diff --git a/drivers/usb/dwc3/gadget.c b/drivers/usb/dwc3/gadget.c
index 0967b5d8fb75..7b8c1c8574f9 100644
--- a/drivers/usb/dwc3/gadget.c
+++ b/drivers/usb/dwc3/gadget.c
@@ -227,10 +227,27 @@ int dwc3_send_gadget_ep_cmd(struct dwc3 *dwc, unsigned ep,
struct dwc3_ep *dep = dwc->eps[ep];
u32 timeout = 500;
u32 reg;
+
+ int susphy = false;
int ret = -EINVAL;
trace_dwc3_gadget_ep_cmd(dep, cmd, params);
+ /*
+ * Synopsys Databook 2.60a states, on section 6.3.2.5.[1-8], that if
+ * we're issuing an endpoint command, we must check if
+ * GUSB2PHYCFG.SUSPHY bit is set. If it is, then we need to clear it.
+ *
+ * We will also set SUSPHY bit to what it was before returning as stated
+ * by the same section on Synopsys databook.
+ */
+ reg = dwc3_readl(dwc->regs, DWC3_GUSB2PHYCFG(0));
+ if (unlikely(reg & DWC3_GUSB2PHYCFG_SUSPHY)) {
+ susphy = true;
+ reg &= ~DWC3_GUSB2PHYCFG_SUSPHY;
+ dwc3_writel(dwc->regs, DWC3_GUSB2PHYCFG(0), reg);
+ }
+
dwc3_writel(dwc->regs, DWC3_DEPCMDPAR0(ep), params->param0);
dwc3_writel(dwc->regs, DWC3_DEPCMDPAR1(ep), params->param1);
dwc3_writel(dwc->regs, DWC3_DEPCMDPAR2(ep), params->param2);
@@ -263,6 +280,12 @@ int dwc3_send_gadget_ep_cmd(struct dwc3 *dwc, unsigned ep,
udelay(1);
} while (1);
+ if (unlikely(susphy)) {
+ reg = dwc3_readl(dwc->regs, DWC3_GUSB2PHYCFG(0));
+ reg |= DWC3_GUSB2PHYCFG_SUSPHY;
+ dwc3_writel(dwc->regs, DWC3_GUSB2PHYCFG(0), reg);
+ }
+
return ret;
}
--
2.8.0.rc2
--
balbi
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