lkml.org 
[lkml]   [2014]   [Oct]   [30]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
    Patch in this message
    /
    From
    Subject[PATCH v4 14/20] usb: dwc3: add Tx de-emphasis quirk
    Date
    This patch adds Tx de-emphasis quirk, and the Tx de-emphasis value is
    configurable according to PIPE3 specification.

    Value Description
    0 -6dB de-emphasis
    1 -3.5dB de-emphasis
    2 No de-emphasis
    3 Reserved

    It can be configured on DT or platform data.

    Signed-off-by: Huang Rui <ray.huang@amd.com>
    ---
    Documentation/devicetree/bindings/usb/dwc3.txt | 3 +++
    drivers/usb/dwc3/core.c | 17 +++++++++++++++++
    drivers/usb/dwc3/core.h | 11 +++++++++++
    drivers/usb/dwc3/platform_data.h | 3 +++
    4 files changed, 34 insertions(+)

    diff --git a/Documentation/devicetree/bindings/usb/dwc3.txt b/Documentation/devicetree/bindings/usb/dwc3.txt
    index 38bac28..a9e54ae 100644
    --- a/Documentation/devicetree/bindings/usb/dwc3.txt
    +++ b/Documentation/devicetree/bindings/usb/dwc3.txt
    @@ -29,6 +29,9 @@ Optional properties:
    - snps,lfps_filter_quirk: when set core will filter LFPS reception.
    - snps,rx_detect_poll_quirk: when set core will disable a 400us delay to start
    Polling LFPS after RX.Detect.
    + - snps,tx_de_emphasis_quirk: when set core will set Tx de-emphasis value.
    + - snps,tx_de_emphasis: the value driven to the PHY is controlled by the
    + LTSSM during USB3 Compliance mode.

    This is usually a subnode to DWC3 glue to which it is connected.

    diff --git a/drivers/usb/dwc3/core.c b/drivers/usb/dwc3/core.c
    index e02c3b0..b55fa5b 100644
    --- a/drivers/usb/dwc3/core.c
    +++ b/drivers/usb/dwc3/core.c
    @@ -401,6 +401,9 @@ static void dwc3_phy_setup(struct dwc3 *dwc)
    if (dwc->rx_detect_poll_quirk)
    reg |= DWC3_GUSB3PIPECTL_RX_DETOPOLL;

    + if (dwc->tx_de_emphasis_quirk)
    + reg |= DWC3_GUSB3PIPECTL_TX_DEEPH(dwc->tx_de_emphasis);
    +
    dwc3_writel(dwc->regs, DWC3_GUSB3PIPECTL(0), reg);

    mdelay(100);
    @@ -717,6 +720,7 @@ static int dwc3_probe(struct platform_device *pdev)
    struct resource *res;
    struct dwc3 *dwc;
    u8 lpm_nyet_threshold;
    + u8 tx_de_emphasis;

    int ret;

    @@ -775,6 +779,9 @@ static int dwc3_probe(struct platform_device *pdev)
    /* default to highest possible threshold */
    lpm_nyet_threshold = 0xff;

    + /* default to -3.5dB de-emphasis */
    + tx_de_emphasis = 1;
    +
    if (node) {
    dwc->maximum_speed = of_usb_get_maximum_speed(node);
    dwc->has_lpm_erratum = of_property_read_bool(node,
    @@ -802,6 +809,11 @@ static int dwc3_probe(struct platform_device *pdev)
    "snps,lfps_filter_quirk");
    dwc->rx_detect_poll_quirk = of_property_read_bool(node,
    "snps,rx_detect_poll_quirk");
    +
    + dwc->tx_de_emphasis_quirk = of_property_read_bool(node,
    + "snps,tx_de_emphasis_quirk");
    + of_property_read_u8(node, "snps,tx_de_emphasis",
    + &tx_de_emphasis);
    } else if (pdata) {
    dwc->maximum_speed = pdata->maximum_speed;
    dwc->has_lpm_erratum = pdata->has_lpm_erratum;
    @@ -819,6 +831,10 @@ static int dwc3_probe(struct platform_device *pdev)
    dwc->del_phy_power_chg_quirk = pdata->del_phy_power_chg_quirk;
    dwc->lfps_filter_quirk = pdata->lfps_filter_quirk;
    dwc->rx_detect_poll_quirk = pdata->rx_detect_poll_quirk;
    +
    + dwc->tx_de_emphasis_quirk = pdata->tx_de_emphasis_quirk;
    + if (pdata->tx_de_emphasis)
    + tx_de_emphasis = pdata->tx_de_emphasis;
    }

    /* default to superspeed if no maximum_speed passed */
    @@ -826,6 +842,7 @@ static int dwc3_probe(struct platform_device *pdev)
    dwc->maximum_speed = USB_SPEED_SUPER;

    dwc->lpm_nyet_threshold = lpm_nyet_threshold;
    + dwc->tx_de_emphasis = tx_de_emphasis;

    ret = dwc3_core_get_phy(dwc);
    if (ret)
    diff --git a/drivers/usb/dwc3/core.h b/drivers/usb/dwc3/core.h
    index eeef976..469ee13 100644
    --- a/drivers/usb/dwc3/core.h
    +++ b/drivers/usb/dwc3/core.h
    @@ -185,6 +185,8 @@
    #define DWC3_GUSB3PIPECTL_SUSPHY (1 << 17)
    #define DWC3_GUSB3PIPECTL_LFPSFILT (1 << 9)
    #define DWC3_GUSB3PIPECTL_RX_DETOPOLL (1 << 8)
    +#define DWC3_GUSB3PIPECTL_TX_DEEPH_MASK DWC3_GUSB3PIPECTL_TX_DEEPH(3)
    +#define DWC3_GUSB3PIPECTL_TX_DEEPH(n) ((n) << 1)

    /* Global TX Fifo Size Register */
    #define DWC3_GTXFIFOSIZ_TXFDEF(n) ((n) & 0xffff)
    @@ -695,6 +697,12 @@ struct dwc3_scratchpad_array {
    * @del_phy_power_chg_quirk: set if we enable delay phy power change quirk
    * @lfps_filter_quirk: set if we enable LFPS filter quirk
    * @rx_detect_poll_quirk: set if we enable rx_detect to polling LFPS quirk
    + * @tx_de_emphasis_quirk: set if we enable Tx de-emphasis quirk
    + * @tx_de_emphasis: Tx de-emphasis value
    + * 0 - -6dB de-emphasis
    + * 1 - -3.5dB de-emphasis
    + * 2 - No de-emphasis
    + * 3 - Reserved
    */
    struct dwc3 {
    struct usb_ctrlrequest *ctrl_req;
    @@ -810,6 +818,9 @@ struct dwc3 {
    unsigned del_phy_power_chg_quirk:1;
    unsigned lfps_filter_quirk:1;
    unsigned rx_detect_poll_quirk:1;
    +
    + unsigned tx_de_emphasis_quirk:1;
    + unsigned tx_de_emphasis:2;
    };

    /* -------------------------------------------------------------------------- */
    diff --git a/drivers/usb/dwc3/platform_data.h b/drivers/usb/dwc3/platform_data.h
    index 4a0f06b..e1ab900 100644
    --- a/drivers/usb/dwc3/platform_data.h
    +++ b/drivers/usb/dwc3/platform_data.h
    @@ -36,4 +36,7 @@ struct dwc3_platform_data {
    unsigned del_phy_power_chg_quirk:1;
    unsigned lfps_filter_quirk:1;
    unsigned rx_detect_poll_quirk:1;
    +
    + unsigned tx_de_emphasis_quirk:1;
    + unsigned tx_de_emphasis:2;
    };
    --
    1.9.1


    \
     
     \ /
      Last update: 2014-10-30 11:21    [W:4.555 / U:0.028 seconds]
    ©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site