+++ /dev/null
-From 61d471c8da972c7ebbaf63779bf8100ee1ec54eb Mon Sep 17 00:00:00 2001
-From: Ran Wang <ran.wang_1@nxp.com>
-Date: Wed, 16 Jan 2019 13:23:17 +0800
-Subject: [PATCH] usb: dwc3: Add workaround for host mode VBUS glitch when boot
-
-When DWC3 is set to host mode by programming register DWC3_GCTL, VBUS
-(or its control signal) will be turned on immediately on related Root Hub
-ports. Then, the VBUS is turned off for a little while(15us) when do xhci
-reset (conducted by xhci driver) and back to normal finally, we can
-observe a negative glitch of related signal happen.
-
-This VBUS glitch might cause some USB devices enumeration fail if kernel
-boot with them connected. Such as LS1012AFWRY/LS1043ARDB/LX2160AQDS
-/LS1088ARDB with Kingston 16GB USB2.0/Kingston USB3.0/JetFlash Transcend
-4GB USB2.0 drives. The fail cases include enumerated as full-speed device
-or report wrong device descriptor, etc.
-
-One SW workaround which can fix this is by programing all xhci PORTSC[PP]
-to 0 to turn off VBUS immediately after setting host mode in DWC3 driver
-(per signal measurement result, it will be too late to do it in
-xhci-plat.c or xhci.c). Then, after xhci reset complete in xhci driver,
-PORTSC[PP]s' value will back to 1 automatically and VBUS on at that time,
-no glitch happen and normal enumeration process has no impact.
-
-Signed-off-by: Ran Wang <ran.wang_1@nxp.com>
-Reviewed-by: Peter Chen <peter.chen@nxp.com>
----
- drivers/usb/dwc3/core.c | 3 +++
- drivers/usb/dwc3/core.h | 3 +++
- drivers/usb/dwc3/host.c | 48 ++++++++++++++++++++++++++++++++++++++++++++++++
- 3 files changed, 54 insertions(+)
-
---- a/drivers/usb/dwc3/core.c
-+++ b/drivers/usb/dwc3/core.c
-@@ -1364,6 +1364,9 @@ static void dwc3_get_properties(struct d
- dwc->dis_split_quirk = device_property_read_bool(dev,
- "snps,dis-split-quirk");
-
-+ dwc->host_vbus_glitches = device_property_read_bool(dev,
-+ "snps,host-vbus-glitches");
-+
- dwc->lpm_nyet_threshold = lpm_nyet_threshold;
- dwc->tx_de_emphasis = tx_de_emphasis;
-
---- a/drivers/usb/dwc3/core.h
-+++ b/drivers/usb/dwc3/core.h
-@@ -1048,6 +1048,8 @@ struct dwc3_scratchpad_array {
- * 3 - Reserved
- * @dis_metastability_quirk: set to disable metastability quirk.
- * @dis_split_quirk: set to disable split boundary.
-+ * @host_vbus_glitches: set to avoid vbus glitch during
-+ * xhci reset.
- * @imod_interval: set the interrupt moderation interval in 250ns
- * increments or 0 to disable.
- */
-@@ -1243,6 +1245,8 @@ struct dwc3 {
-
- unsigned dis_split_quirk:1;
-
-+ unsigned host_vbus_glitches:1;
-+
- u16 imod_interval;
- };
-
---- a/drivers/usb/dwc3/host.c
-+++ b/drivers/usb/dwc3/host.c
-@@ -9,8 +9,49 @@
-
- #include <linux/platform_device.h>
-
-+#include "../host/xhci.h"
-+
- #include "core.h"
-
-+
-+#define XHCI_HCSPARAMS1 0x4
-+#define XHCI_PORTSC_BASE 0x400
-+
-+/*
-+ * dwc3_power_off_all_roothub_ports - Power off all Root hub ports
-+ * @dwc3: Pointer to our controller context structure
-+ */
-+static void dwc3_power_off_all_roothub_ports(struct dwc3 *dwc)
-+{
-+ int i, port_num;
-+ u32 reg, op_regs_base, offset;
-+ void __iomem *xhci_regs;
-+
-+ /* xhci regs is not mapped yet, do it temperary here */
-+ if (dwc->xhci_resources[0].start) {
-+ xhci_regs = ioremap(dwc->xhci_resources[0].start,
-+ DWC3_XHCI_REGS_END);
-+ if (IS_ERR(xhci_regs)) {
-+ dev_err(dwc->dev, "Failed to ioremap xhci_regs\n");
-+ return;
-+ }
-+
-+ op_regs_base = HC_LENGTH(readl(xhci_regs));
-+ reg = readl(xhci_regs + XHCI_HCSPARAMS1);
-+ port_num = HCS_MAX_PORTS(reg);
-+
-+ for (i = 1; i <= port_num; i++) {
-+ offset = op_regs_base + XHCI_PORTSC_BASE + 0x10*(i-1);
-+ reg = readl(xhci_regs + offset);
-+ reg &= ~PORT_POWER;
-+ writel(reg, xhci_regs + offset);
-+ }
-+
-+ iounmap(xhci_regs);
-+ } else
-+ dev_err(dwc->dev, "xhci base reg invalid\n");
-+}
-+
- static int dwc3_host_get_irq(struct dwc3 *dwc)
- {
- struct platform_device *dwc3_pdev = to_platform_device(dwc->dev);
-@@ -50,6 +91,13 @@ int dwc3_host_init(struct dwc3 *dwc)
- struct platform_device *dwc3_pdev = to_platform_device(dwc->dev);
- int prop_idx = 0;
-
-+ /*
-+ * We have to power off all Root hub ports immediately after DWC3 set
-+ * to host mode to avoid VBUS glitch happen when xhci get reset later.
-+ */
-+ if (dwc->host_vbus_glitches)
-+ dwc3_power_off_all_roothub_ports(dwc);
-+
- irq = dwc3_host_get_irq(dwc);
- if (irq < 0)
- return irq;
projects / openwrt / staging / chunkeey.git / blobdiff