[U-Boot] [PATCH v2 2/5] usb: host: add error path and remove callback in ehci-generic

[Simon Glass]

Hi Patrice,

On 12 May 2017 at 11:27,  <patrice.chotard at st.com> wrote:
> From: Patrice Chotard <patrice.chotard at st.com>
>
> Add error path to disable enabled clocks and to assert
> deasserted resets
> Populate the remove callback
>
> Signed-off-by: Patrice Chotard <patrice.chotard at st.com>
> ---
> v2:     _ split previous path 1, add error path and .remove callback
>
>  drivers/usb/host/ehci-generic.c | 81 +++++++++++++++++++++++++++++++++++------
>  1 file changed, 70 insertions(+), 11 deletions(-)

Reviewed-by: Simon Glass <sjg at chromium.org>

Please see below.

>
> diff --git a/drivers/usb/host/ehci-generic.c b/drivers/usb/host/ehci-generic.c
> index 2190adb..0c29f63 100644
> --- a/drivers/usb/host/ehci-generic.c
> +++ b/drivers/usb/host/ehci-generic.c
> @@ -11,6 +11,9 @@
>  #include <dm.h>
>  #include "ehci.h"
>
> +#define EHCI_MAX_CLOCKS 3
> +#define EHCI_MAX_RESETS 3
> +
>  /*
>   * Even though here we don't explicitly use "struct ehci_ctrl"
>   * ehci_register() expects it to be the first thing that resides in
> @@ -18,35 +21,74 @@
>   */
>  struct generic_ehci {
>         struct ehci_ctrl ctrl;
> +       struct clk clks[EHCI_MAX_CLOCKS];
> +       struct reset_ctl resets[EHCI_MAX_RESETS];
>  };
>
> +static void ehci_assert_resets(struct udevice *dev) {
> +       struct generic_ehci *priv = dev_get_priv(dev);

You could pass priv instead of dev to avoid this line.

> +       struct reset_ctl reset;
> +       int i;
> +
> +       for (i = EHCI_MAX_RESETS; i >= 0; --i) {
> +               reset = priv->resets[i];
> +
> +               if (reset.dev) {
> +                        reset_request(&reset);
> +                        reset_assert(&reset);
> +                        reset_free(&reset);
> +               }
> +       }
> +}
> +
> +static void ehci_disable_clocks(struct udevice *dev) {
> +       struct generic_ehci *priv = dev_get_priv(dev);
> +       struct clk clk;
> +       int i;
> +
> +       for (i = EHCI_MAX_CLOCKS; i >= 0; --i) {

Do you think it is worth adding a function in the uclass to do this to
a list of clks?

> +               clk = priv->clks[i];
> +
> +               if (clk.dev) {
> +                       clk_request(clk.dev, &clk);
> +                       clk_disable(&clk);
> +                       clk_free(&clk);
> +               }
> +       }
> +}
> +
>  static int ehci_usb_probe(struct udevice *dev)
>  {
> +       struct generic_ehci *priv = dev_get_priv(dev);
>         struct ehci_hccr *hccr;
>         struct ehci_hcor *hcor;
> -       int i;
> +       int i, ret;
>
> -       for (i = 0; ; i++) {
> -               struct clk clk;
> -               int ret;
> +       for (i = 0; i < EHCI_MAX_CLOCKS; i++) {
> +               struct clk clk = priv->clks[i];
>
>                 ret = clk_get_by_index(dev, i, &clk);
>                 if (ret < 0)
>                         break;
> -               if (clk_enable(&clk))
> +               if (clk_enable(&clk)) {
>                         printf("failed to enable clock %d\n", i);
> +                       clk_free(&clk);
> +                       goto clk_err;
> +               }
>                 clk_free(&clk);
>         }
>
> -       for (i = 0; ; i++) {
> -               struct reset_ctl reset;
> -               int ret;
> +       for (i = 0; i < EHCI_MAX_RESETS ; i++) {
> +               struct reset_ctl reset = priv->resets[i];
>
>                 ret = reset_get_by_index(dev, i, &reset);
>                 if (ret < 0)
>                         break;
> -               if (reset_deassert(&reset))
> +               if (reset_deassert(&reset)) {
>                         printf("failed to deassert reset %d\n", i);
> +                       reset_free(&reset);
> +                       goto reset_err;
> +               }
>                 reset_free(&reset);
>         }
>
> @@ -54,7 +96,24 @@ static int ehci_usb_probe(struct udevice *dev)
>         hcor = (struct ehci_hcor *)((uintptr_t)hccr +
>                                     HC_LENGTH(ehci_readl(&hccr->cr_capbase)));
>
> -       return ehci_register(dev, hccr, hcor, NULL, 0, USB_INIT_HOST);
> +       ret = ehci_register(dev, hccr, hcor, NULL, 0, USB_INIT_HOST);
> +       if (!ret)
> +               return ret;
> +
> +reset_err:
> +       ehci_assert_resets(dev);
> +clk_err:
> +       ehci_disable_clocks(dev);
> +
> +       return ret;
> +}
> +
> +static int ehci_usb_remove(struct udevice *dev) {
> +
> +       ehci_assert_resets(dev);
> +       ehci_disable_clocks(dev);
> +
> +       return ehci_deregister(dev);
>  }
>
>  static const struct udevice_id ehci_usb_ids[] = {
> @@ -67,7 +126,7 @@ U_BOOT_DRIVER(ehci_generic) = {
>         .id     = UCLASS_USB,
>         .of_match = ehci_usb_ids,
>         .probe = ehci_usb_probe,
> -       .remove = ehci_deregister,
> +       .remove = ehci_usb_remove,
>         .ops    = &ehci_usb_ops,
>         .priv_auto_alloc_size = sizeof(struct generic_ehci),
>         .flags  = DM_FLAG_ALLOC_PRIV_DMA,
> --
> 1.9.1
>

Regards,
Simon