I can't find any erratas this is in refernce to, but apparently external changer detector needs to be disabled to prevent poor USB data signal quality. The problem manifest itself as a intermittent USB transfer corruption that happens to some device under and only under specific circumstances.
In my case the failure was observed with Transcent SD/micro-SD card reader (05e3:0745 Genesys Logic, Inc. Logilink CR0012) when connected directly to front panel USB of ZII RDU2 board (the problem would go away if device was conntecte via a hub/USB-analyzer/male-female type A extender cable). Note that this fix is present in Linux kernel as well as some abandoned Barebox code removed in the next patch. Signed-off-by: Andrey Smirnov <[email protected]> --- drivers/usb/imx/imx-usb-phy.c | 37 +++++++++++++++++++++++++++++++++++ 1 file changed, 37 insertions(+) diff --git a/drivers/usb/imx/imx-usb-phy.c b/drivers/usb/imx/imx-usb-phy.c index 306f84374..d4562285c 100644 --- a/drivers/usb/imx/imx-usb-phy.c +++ b/drivers/usb/imx/imx-usb-phy.c @@ -24,6 +24,7 @@ #include <linux/clk.h> #include <linux/err.h> #include <stmp-device.h> +#include <mfd/syscon.h> #define HW_USBPHY_PWD 0x00 #define HW_USBPHY_TX 0x10 @@ -35,12 +36,19 @@ #define BM_USBPHY_CTRL_ENUTMILEVEL2 BIT(14) #define BM_USBPHY_CTRL_ENHOSTDISCONDETECT BIT(1) +#define ANADIG_USB1_CHRG_DETECT_SET 0x1b4 +#define ANADIG_USB2_CHRG_DETECT_SET 0x214 +#define ANADIG_USB1_CHRG_DETECT_EN_B BIT(20) +#define ANADIG_USB1_CHRG_DETECT_CHK_CHRG_B BIT(19) + struct imx_usbphy { struct usb_phy usb_phy; struct phy *phy; void __iomem *base; + void __iomem *anatop; struct clk *clk; struct phy_provider *provider; + int port_id; }; static int imx_usbphy_phy_init(struct phy *phy) @@ -61,6 +69,19 @@ static int imx_usbphy_phy_init(struct phy *phy) writel(BM_USBPHY_CTRL_ENUTMILEVEL3 | BM_USBPHY_CTRL_ENUTMILEVEL2, imxphy->base + HW_USBPHY_CTRL_SET); + if (imxphy->anatop) { + unsigned int reg = imxphy->port_id ? + ANADIG_USB1_CHRG_DETECT_SET : + ANADIG_USB2_CHRG_DETECT_SET; + /* + * The external charger detector needs to be disabled, + * or the signal at DP will be poor + */ + writel(ANADIG_USB1_CHRG_DETECT_EN_B | + ANADIG_USB1_CHRG_DETECT_CHK_CHRG_B, + imxphy->anatop + reg); + } + return 0; } @@ -113,11 +134,27 @@ static const struct phy_ops imx_phy_ops = { static int imx_usbphy_probe(struct device_d *dev) { struct resource *iores; + struct device_node *np = dev->device_node; int ret; struct imx_usbphy *imxphy; imxphy = xzalloc(sizeof(*imxphy)); + ret = of_alias_get_id(np, "usbphy"); + if (ret < 0) { + dev_dbg(dev, "failed to get alias id, errno %d\n", ret); + goto err_free; + } + imxphy->port_id = ret; + + if (of_get_property(np, "fsl,anatop", NULL)) { + imxphy->anatop = + syscon_base_lookup_by_phandle(np, "fsl,anatop"); + ret = PTR_ERR_OR_ZERO(imxphy->anatop); + if (ret) + goto err_free; + } + iores = dev_request_mem_resource(dev, 0); if (IS_ERR(iores)) { ret = PTR_ERR(iores); -- 2.21.0 _______________________________________________ barebox mailing list [email protected] http://lists.infradead.org/mailman/listinfo/barebox
