On Thu, Sep 10, 2020 at 04:21:45PM +0800, Chunfeng Yun wrote:
> Use readl_poll_timeout_atomic() to simplify code
>
> Cc: Mathias Nyman <mathias.nyman@xxxxxxxxxxxxxxx>
> Cc: Yoshihiro Shimoda <yoshihiro.shimoda.uh@xxxxxxxxxxx>
> Signed-off-by: Chunfeng Yun <chunfeng.yun@xxxxxxxxxxxx>
> ---
> v2~v3: no changes
> ---
> drivers/usb/host/xhci-rcar.c | 43 ++++++++++++-------------------------------
> 1 file changed, 12 insertions(+), 31 deletions(-)
>
> diff --git a/drivers/usb/host/xhci-rcar.c b/drivers/usb/host/xhci-rcar.c
> index c1025d3..74f836f 100644
> --- a/drivers/usb/host/xhci-rcar.c
> +++ b/drivers/usb/host/xhci-rcar.c
> @@ -6,6 +6,7 @@
> */
>
> #include <linux/firmware.h>
> +#include <linux/iopoll.h>
> #include <linux/module.h>
> #include <linux/platform_device.h>
> #include <linux/of.h>
> @@ -127,8 +128,7 @@ static int xhci_rcar_download_firmware(struct usb_hcd *hcd)
> void __iomem *regs = hcd->regs;
> struct xhci_plat_priv *priv = hcd_to_xhci_priv(hcd);
> const struct firmware *fw;
> - int retval, index, j, time;
> - int timeout = 10000;
> + int retval, index, j;
> u32 data, val, temp;
> u32 quirks = 0;
> const struct soc_device_attribute *attr;
> @@ -166,32 +166,19 @@ static int xhci_rcar_download_firmware(struct usb_hcd *hcd)
> temp |= RCAR_USB3_DL_CTRL_FW_SET_DATA0;
> writel(temp, regs + RCAR_USB3_DL_CTRL);
>
> - for (time = 0; time < timeout; time++) {
> - val = readl(regs + RCAR_USB3_DL_CTRL);
> - if ((val & RCAR_USB3_DL_CTRL_FW_SET_DATA0) == 0)
> - break;
> - udelay(1);
> - }
> - if (time == timeout) {
> - retval = -ETIMEDOUT;
> + retval = readl_poll_timeout_atomic(regs + RCAR_USB3_DL_CTRL,
> + val, !(val & RCAR_USB3_DL_CTRL_FW_SET_DATA0),
> + 1, 10000);
> + if (retval < 0)
> break;
> - }
> }
>
> temp = readl(regs + RCAR_USB3_DL_CTRL);
> temp &= ~RCAR_USB3_DL_CTRL_ENABLE;
> writel(temp, regs + RCAR_USB3_DL_CTRL);
>
> - for (time = 0; time < timeout; time++) {
> - val = readl(regs + RCAR_USB3_DL_CTRL);
> - if (val & RCAR_USB3_DL_CTRL_FW_SUCCESS) {
> - retval = 0;
> - break;
> - }
> - udelay(1);
> - }
> - if (time == timeout)
> - retval = -ETIMEDOUT;
> + retval = readl_poll_timeout_atomic((regs + RCAR_USB3_DL_CTRL),
> + val, (val & RCAR_USB3_DL_CTRL_FW_SUCCESS), 1, 10000);
Directly assigning to retval at this point will clobber a previous
-ETIMEDOUT error.
In other words if there is a timeout waiting for FW_SET_DATA0, but not for
DW_SUCCESS, then we will return the wrong return value.
Daniel.
>
> release_firmware(fw);
>
> @@ -200,18 +187,12 @@ static int xhci_rcar_download_firmware(struct usb_hcd *hcd)
>
> static bool xhci_rcar_wait_for_pll_active(struct usb_hcd *hcd)
> {
> - int timeout = 1000;
> + int retval;
> u32 val, mask = RCAR_USB3_AXH_STA_PLL_ACTIVE_MASK;
>
> - while (timeout > 0) {
> - val = readl(hcd->regs + RCAR_USB3_AXH_STA);
> - if ((val & mask) == mask)
> - return true;
> - udelay(1);
> - timeout--;
> - }
> -
> - return false;
> + retval = readl_poll_timeout_atomic(hcd->regs + RCAR_USB3_AXH_STA,
> + val, ((val & mask) == mask), 1, 1000);
> + return !!retval;
This function returns a bool so !! is either wrong or redundant... I
think in this case it is wrong and should be a single ! .
Daniel.
