lkml.org 
[lkml]   [2022]   [Aug]   [16]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
    Patch in this message
    /
    From
    Subject[PATCH 5.19 0613/1157] usb: host: ohci-at91: add support to enter suspend using SMC
    Date
    From: Clément Léger <clement.leger@bootlin.com>

    [ Upstream commit 1e073e3ed9ff9ec14e7e360ed89a81256d895588 ]

    When Linux is running under OP-TEE, the SFR is set as secured and thus
    the AT91_OHCIICR_USB_SUSPEND register isn't accessible. Add a SMC to
    do the appropriate call to suspend the controller.
    The SMC id is fetched from the device-tree property
    "microchip,suspend-smc-id". if present, then the syscon regmap is not
    used to enter suspend and a SMC is issued.

    Reviewed-by: Claudiu Beznea <claudiu.beznea@microchip.com>
    Acked-by: Alan Stern <stern@rowland.harvard.edu>
    Signed-off-by: Clément Léger <clement.leger@bootlin.com>
    Link: https://lore.kernel.org/r/20220607133454.727063-1-clement.leger@bootlin.com
    Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
    Signed-off-by: Sasha Levin <sashal@kernel.org>
    ---
    drivers/usb/host/ohci-at91.c | 69 ++++++++++++++++++++++++------------
    1 file changed, 46 insertions(+), 23 deletions(-)

    diff --git a/drivers/usb/host/ohci-at91.c b/drivers/usb/host/ohci-at91.c
    index a24aea3d2759..98326465e2dc 100644
    --- a/drivers/usb/host/ohci-at91.c
    +++ b/drivers/usb/host/ohci-at91.c
    @@ -13,6 +13,7 @@
    * This file is licenced under the GPL.
    */

    +#include <linux/arm-smccc.h>
    #include <linux/clk.h>
    #include <linux/dma-mapping.h>
    #include <linux/gpio/consumer.h>
    @@ -55,6 +56,7 @@ struct ohci_at91_priv {
    bool clocked;
    bool wakeup; /* Saved wake-up state for resume */
    struct regmap *sfr_regmap;
    + u32 suspend_smc_id;
    };
    /* interface and function clocks; sometimes also an AHB clock */

    @@ -135,6 +137,19 @@ static void at91_stop_hc(struct platform_device *pdev)

    static void usb_hcd_at91_remove (struct usb_hcd *, struct platform_device *);

    +static u32 at91_dt_suspend_smc(struct device *dev)
    +{
    + u32 suspend_smc_id;
    +
    + if (!dev->of_node)
    + return 0;
    +
    + if (of_property_read_u32(dev->of_node, "microchip,suspend-smc-id", &suspend_smc_id))
    + return 0;
    +
    + return suspend_smc_id;
    +}
    +
    static struct regmap *at91_dt_syscon_sfr(void)
    {
    struct regmap *regmap;
    @@ -215,9 +230,13 @@ static int usb_hcd_at91_probe(const struct hc_driver *driver,
    goto err;
    }

    - ohci_at91->sfr_regmap = at91_dt_syscon_sfr();
    - if (!ohci_at91->sfr_regmap)
    - dev_dbg(dev, "failed to find sfr node\n");
    + ohci_at91->suspend_smc_id = at91_dt_suspend_smc(dev);
    + if (!ohci_at91->suspend_smc_id) {
    + dev_dbg(dev, "failed to find sfr suspend smc id, using regmap\n");
    + ohci_at91->sfr_regmap = at91_dt_syscon_sfr();
    + if (!ohci_at91->sfr_regmap)
    + dev_dbg(dev, "failed to find sfr node\n");
    + }

    board = hcd->self.controller->platform_data;
    ohci = hcd_to_ohci(hcd);
    @@ -303,24 +322,30 @@ static int ohci_at91_hub_status_data(struct usb_hcd *hcd, char *buf)
    return length;
    }

    -static int ohci_at91_port_suspend(struct regmap *regmap, u8 set)
    +static int ohci_at91_port_suspend(struct ohci_at91_priv *ohci_at91, u8 set)
    {
    + struct regmap *regmap = ohci_at91->sfr_regmap;
    u32 regval;
    int ret;

    - if (!regmap)
    - return 0;
    + if (ohci_at91->suspend_smc_id) {
    + struct arm_smccc_res res;

    - ret = regmap_read(regmap, AT91_SFR_OHCIICR, &regval);
    - if (ret)
    - return ret;
    + arm_smccc_smc(ohci_at91->suspend_smc_id, set, 0, 0, 0, 0, 0, 0, &res);
    + if (res.a0)
    + return -EINVAL;
    + } else if (regmap) {
    + ret = regmap_read(regmap, AT91_SFR_OHCIICR, &regval);
    + if (ret)
    + return ret;

    - if (set)
    - regval |= AT91_OHCIICR_USB_SUSPEND;
    - else
    - regval &= ~AT91_OHCIICR_USB_SUSPEND;
    + if (set)
    + regval |= AT91_OHCIICR_USB_SUSPEND;
    + else
    + regval &= ~AT91_OHCIICR_USB_SUSPEND;

    - regmap_write(regmap, AT91_SFR_OHCIICR, regval);
    + regmap_write(regmap, AT91_SFR_OHCIICR, regval);
    + }

    return 0;
    }
    @@ -357,9 +382,8 @@ static int ohci_at91_hub_control(struct usb_hcd *hcd, u16 typeReq, u16 wValue,

    case USB_PORT_FEAT_SUSPEND:
    dev_dbg(hcd->self.controller, "SetPortFeat: SUSPEND\n");
    - if (valid_port(wIndex) && ohci_at91->sfr_regmap) {
    - ohci_at91_port_suspend(ohci_at91->sfr_regmap,
    - 1);
    + if (valid_port(wIndex)) {
    + ohci_at91_port_suspend(ohci_at91, 1);
    return 0;
    }
    break;
    @@ -400,9 +424,8 @@ static int ohci_at91_hub_control(struct usb_hcd *hcd, u16 typeReq, u16 wValue,

    case USB_PORT_FEAT_SUSPEND:
    dev_dbg(hcd->self.controller, "ClearPortFeature: SUSPEND\n");
    - if (valid_port(wIndex) && ohci_at91->sfr_regmap) {
    - ohci_at91_port_suspend(ohci_at91->sfr_regmap,
    - 0);
    + if (valid_port(wIndex)) {
    + ohci_at91_port_suspend(ohci_at91, 0);
    return 0;
    }
    break;
    @@ -630,10 +653,10 @@ ohci_hcd_at91_drv_suspend(struct device *dev)
    /* flush the writes */
    (void) ohci_readl (ohci, &ohci->regs->control);
    msleep(1);
    - ohci_at91_port_suspend(ohci_at91->sfr_regmap, 1);
    + ohci_at91_port_suspend(ohci_at91, 1);
    at91_stop_clock(ohci_at91);
    } else {
    - ohci_at91_port_suspend(ohci_at91->sfr_regmap, 1);
    + ohci_at91_port_suspend(ohci_at91, 1);
    }

    return ret;
    @@ -645,7 +668,7 @@ ohci_hcd_at91_drv_resume(struct device *dev)
    struct usb_hcd *hcd = dev_get_drvdata(dev);
    struct ohci_at91_priv *ohci_at91 = hcd_to_ohci_at91_priv(hcd);

    - ohci_at91_port_suspend(ohci_at91->sfr_regmap, 0);
    + ohci_at91_port_suspend(ohci_at91, 0);

    if (ohci_at91->wakeup)
    disable_irq_wake(hcd->irq);
    --
    2.35.1


    \
     
     \ /
      Last update: 2022-08-16 06:34    [W:4.094 / U:0.356 seconds]
    ©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site