linux-kernel - [PATCH 3/6] usb: dwc3: Calculate REFCLKPER based on reference clock

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Date:   Fri, 14 Jan 2022 18:39:01 -0500
From:   Sean Anderson <sean.anderson@...o.com>
To:     Greg Kroah-Hartman <gregkh@...uxfoundation.org>,
        linux-usb@...r.kernel.org
Cc:     linux-kernel@...r.kernel.org,
        Robert Hancock <robert.hancock@...ian.com>,
        Baruch Siach <baruch@...s.co.il>,
        Felipe Balbi <balbi@...nel.org>,
        Balaji Prakash J <bjagadee@...eaurora.org>,
        Sean Anderson <sean.anderson@...o.com>
Subject: [PATCH 3/6] usb: dwc3: Calculate REFCLKPER based on reference clock

Instead of using a special property to determine the reference clock
period, use the rate of the reference clock. When we have a legacy
snps,ref-clock-period-ns property and no reference clock, use it
instead. Fractional clocks are not currently supported, and will be
dealt with in the next commit.

Signed-off-by: Sean Anderson <sean.anderson@...o.com>
---

 drivers/usb/dwc3/core.c | 13 +++++++++++--
 1 file changed, 11 insertions(+), 2 deletions(-)

diff --git a/drivers/usb/dwc3/core.c b/drivers/usb/dwc3/core.c
index 699ab9abdc47..5214daceda86 100644
--- a/drivers/usb/dwc3/core.c
+++ b/drivers/usb/dwc3/core.c
@@ -348,13 +348,22 @@ static void dwc3_frame_length_adjustment(struct dwc3 *dwc)
 static void dwc3_ref_clk_period(struct dwc3 *dwc)
 {
 	u32 reg;
+	unsigned long rate, period;
 
-	if (dwc->ref_clk_per == 0)
+	if (dwc->ref_clk) {
+		rate = clk_get_rate(dwc->ref_clk);
+		if (!rate)
+			return;
+		period = NSEC_PER_SEC / rate;
+	} else if (dwc->ref_clk_per) {
+		period = dwc->ref_clk_per;
+	} else {
 		return;
+	}
 
 	reg = dwc3_readl(dwc->regs, DWC3_GUCTL);
 	reg &= ~DWC3_GUCTL_REFCLKPER_MASK;
-	reg |=  FIELD_PREP(DWC3_GUCTL_REFCLKPER_MASK, dwc->ref_clk_per);
+	reg |=  FIELD_PREP(DWC3_GUCTL_REFCLKPER_MASK, period);
 	dwc3_writel(dwc->regs, DWC3_GUCTL, reg);
 }
 
-- 
2.25.1