diff options
Diffstat (limited to 'target/linux/bcm53xx/patches-4.4/180-usb-xhci-add-support-for-performing-fake-doorbell.patch')
| -rw-r--r-- | target/linux/bcm53xx/patches-4.4/180-usb-xhci-add-support-for-performing-fake-doorbell.patch | 155 |
1 files changed, 155 insertions, 0 deletions
diff --git a/target/linux/bcm53xx/patches-4.4/180-usb-xhci-add-support-for-performing-fake-doorbell.patch b/target/linux/bcm53xx/patches-4.4/180-usb-xhci-add-support-for-performing-fake-doorbell.patch new file mode 100644 index 0000000000..0e8a65a182 --- /dev/null +++ b/target/linux/bcm53xx/patches-4.4/180-usb-xhci-add-support-for-performing-fake-doorbell.patch @@ -0,0 +1,155 @@ +From 37df205cdb69d17d5e815385fc1af3c97d1fe20b Mon Sep 17 00:00:00 2001 +From: =?UTF-8?q?Rafa=C5=82=20Mi=C5=82ecki?= <rafal@milecki.pl> +Date: Sat, 1 Oct 2016 22:54:48 +0200 +Subject: [PATCH] usb: xhci: add support for performing fake doorbell +MIME-Version: 1.0 +Content-Type: text/plain; charset=UTF-8 +Content-Transfer-Encoding: 8bit + +Broadcom's Northstar XHCI controllers seem to need a special start +procedure to work correctly. There isn't any official documentation on +this, the problem is that controller doesn't detect any connected +devices with default setup. Moreover connecting USB device to controller +that doesn't run properly can cause SoC's watchdog issues. + +A workaround that was successfully tested on multiple devices is to +perform a fake doorbell. This patch adds code for doing that and a DT +binding enabling it. + +Signed-off-by: Rafał Miłecki <rafal@milecki.pl> +--- + Documentation/devicetree/bindings/usb/usb-xhci.txt | 2 + + drivers/usb/host/xhci-plat.c | 6 +++ + drivers/usb/host/xhci.c | 63 ++++++++++++++++++++-- + drivers/usb/host/xhci.h | 1 + + 4 files changed, 69 insertions(+), 3 deletions(-) + +--- a/Documentation/devicetree/bindings/usb/usb-xhci.txt ++++ b/Documentation/devicetree/bindings/usb/usb-xhci.txt +@@ -12,6 +12,8 @@ Required properties: + Optional properties: + - clocks: reference to a clock + - usb3-lpm-capable: determines if platform is USB3 LPM capable ++ - usb3-fake-doorbell: determines if controller requires a fake doorbell when ++ starting it + + Example: + usb@f0931000 { +--- a/drivers/usb/host/xhci-plat.c ++++ b/drivers/usb/host/xhci-plat.c +@@ -38,12 +38,18 @@ static const struct xhci_driver_override + + static void xhci_plat_quirks(struct device *dev, struct xhci_hcd *xhci) + { ++ struct platform_device *pdev = to_platform_device(dev); ++ struct device_node *node = pdev->dev.of_node; ++ + /* + * As of now platform drivers don't provide MSI support so we ensure + * here that the generic code does not try to make a pci_dev from our + * dev struct in order to setup MSI + */ + xhci->quirks |= XHCI_PLAT; ++ ++ if (node && of_property_read_bool(node, "usb3-fake-doorbell")) ++ xhci->quirks |= XHCI_FAKE_DOORBELL; + } + + /* called during probe() after chip reset completes */ +--- a/drivers/usb/host/xhci.c ++++ b/drivers/usb/host/xhci.c +@@ -152,6 +152,49 @@ static int xhci_start(struct xhci_hcd *x + return ret; + } + ++/** ++ * xhci_fake_doorbell - Perform a fake doorbell on a specified slot ++ * ++ * Some controllers require a fake doorbell to start correctly. Without that ++ * they simply don't detect any devices. ++ */ ++static int xhci_fake_doorbell(struct xhci_hcd *xhci, int slot_id) ++{ ++ u32 temp; ++ ++ /* Alloc a virt device for that slot */ ++ if (!xhci_alloc_virt_device(xhci, slot_id, NULL, GFP_NOIO)) { ++ xhci_warn(xhci, "Could not allocate xHCI USB device data structures\n"); ++ return -ENOMEM; ++ } ++ ++ /* Ring fake doorbell for slot_id ep 0 */ ++ xhci_ring_ep_doorbell(xhci, slot_id, 0, 0); ++ usleep_range(1000, 1500); ++ ++ /* Read the status to check if HSE is set or not */ ++ temp = readl(&xhci->op_regs->status); ++ ++ /* Clear HSE if set */ ++ if (temp & STS_FATAL) { ++ xhci_dbg(xhci, "HSE problem detected, status: 0x%08x\n", temp); ++ temp &= ~0x1fff; ++ temp |= STS_FATAL; ++ writel(temp, &xhci->op_regs->status); ++ usleep_range(1000, 1500); ++ readl(&xhci->op_regs->status); ++ } ++ ++ /* Free virt device */ ++ xhci_free_virt_device(xhci, slot_id); ++ ++ /* We're done if controller is already running */ ++ if (readl(&xhci->op_regs->command) & CMD_RUN) ++ return 0; ++ ++ return xhci_start(xhci); ++} ++ + /* + * Reset a halted HC. + * +@@ -568,10 +611,20 @@ int xhci_init(struct usb_hcd *hcd) + + static int xhci_run_finished(struct xhci_hcd *xhci) + { +- if (xhci_start(xhci)) { +- xhci_halt(xhci); +- return -ENODEV; ++ int err; ++ ++ err = xhci_start(xhci); ++ if (err) { ++ err = -ENODEV; ++ goto err_halt; ++ } ++ ++ if (xhci->quirks & XHCI_FAKE_DOORBELL) { ++ err = xhci_fake_doorbell(xhci, 1); ++ if (err) ++ goto err_halt; + } ++ + xhci->shared_hcd->state = HC_STATE_RUNNING; + xhci->cmd_ring_state = CMD_RING_STATE_RUNNING; + +@@ -581,6 +634,10 @@ static int xhci_run_finished(struct xhci + xhci_dbg_trace(xhci, trace_xhci_dbg_init, + "Finished xhci_run for USB3 roothub"); + return 0; ++ ++err_halt: ++ xhci_halt(xhci); ++ return err; + } + + /* +--- a/drivers/usb/host/xhci.h ++++ b/drivers/usb/host/xhci.h +@@ -1631,6 +1631,7 @@ struct xhci_hcd { + /* For controllers with a broken beyond repair streams implementation */ + #define XHCI_BROKEN_STREAMS (1 << 19) + #define XHCI_PME_STUCK_QUIRK (1 << 20) ++#define XHCI_FAKE_DOORBELL (1 << 24) + unsigned int num_active_eps; + unsigned int limit_active_eps; + /* There are two roothubs to keep track of bus suspend info for */ |