Message ID | 1475464365-18437-9-git-send-email-sjg@chromium.org |
---|---|
State | Superseded |
Delegated to: | Bin Meng |
Headers | show |
Hi Simon, On Mon, Oct 3, 2016 at 11:12 AM, Simon Glass <sjg@chromium.org> wrote: > At present all video devices are probed on start-up. It would be better to > probe a device only when it is needed. This can happen if it is referenced > in the stdout environment variable, for example. > > Add support for this by searching for a suitable device when needed, probing > it, and finding the stdio device it creates. > > Signed-off-by: Simon Glass <sjg@chromium.org> > --- > > common/stdio.c | 67 ++++++++++++++++++++++++++++++++++++++++++++++++++++++---- > 1 file changed, 63 insertions(+), 4 deletions(-) > > diff --git a/common/stdio.c b/common/stdio.c > index f99cfe7..b58b3c7 100644 > --- a/common/stdio.c > +++ b/common/stdio.c > @@ -121,19 +121,76 @@ struct list_head* stdio_get_list(void) > return &(devs.list); > } > > +#ifdef CONFIG_DM_VIDEO > +/** > + * stdio_probe_device() - Find a device which provides the given stdio device > + * > + * This looks for a device of the given uclass which provides a particular > + * stdio device. It is currently really only useful for UCLASS_VIDEO. > + * > + * Ultimately we want to be able to probe a device by its stdio name. At > + * present devices register in their probe function (for video devices this > + * is done in vidconsole_post_probe()) and we don't know what name they will > + * use until they do so. > + * TODO(sjg@chromium.org): We should be able to determine the name before > + * probing, and probe the required device. > + * > + * @name: stdio device name (e.g. "vidconsole") > + * id: Uclass ID of device to look for (e.g. UCLASS_VIDEO) > + * @sdevp: Returns stdout device, if found, else NULL > + * @return 0 if found, -ENOENT if no device found with that name, other -ve > + * on other error > + */ > +static int stdio_probe_device(const char *name, enum uclass_id id, > + struct stdio_dev **sdevp) > +{ > + struct stdio_dev *sdev; > + struct udevice *dev; > + int seq, ret; > + > + *sdevp = NULL; > + seq = trailing_strtoln(name, NULL); > + if (seq == -1) > + ret = uclass_first_device_err(id, &dev); > + else > + ret = uclass_get_device_by_seq(id, seq, &dev); > + if (ret) { > + debug("No %s device for seq %d (%s)\n", uclass_get_name(id), > + seq, name); > + return ret; > + } > + /* The device should be be the last one registered */ > + sdev = list_empty(&devs.list) ? NULL : > + list_last_entry(&devs.list, struct stdio_dev, list); > + if (!sdev || strcmp(sdev->name, name)) { > + debug("Device '%s' did not register with stdio as '%s'\n", > + dev->name, name); > + return -ENOENT; > + } > + *sdevp = sdev; > + > + return 0; > +} > +#endif > + > struct stdio_dev* stdio_get_by_name(const char *name) > { > struct list_head *pos; > - struct stdio_dev *dev; > + struct stdio_dev *sdev; > > if(!name) > return NULL; > > list_for_each(pos, &(devs.list)) { > - dev = list_entry(pos, struct stdio_dev, list); > - if(strcmp(dev->name, name) == 0) > - return dev; > + sdev = list_entry(pos, struct stdio_dev, list); > + if (strcmp(sdev->name, name) == 0) > + return sdev; > } > +#ifdef CONFIG_DM_VIDEO > + if (!strncmp(name, "vidconsole", 10) && !strchr(name, ',') && Why is strchr(name, ',') needed? > + !stdio_probe_device(name, UCLASS_VIDEO, &sdev)) > + return sdev; > +#endif > > return NULL; > } > @@ -282,6 +339,7 @@ int stdio_add_devices(void) > #endif > #endif > #ifdef CONFIG_DM_VIDEO > +#ifndef CONFIG_SYS_CONSOLE_IS_IN_ENV Wy adding CONFIG_SYS_CONSOLE_IS_IN_ENV check? > struct udevice *vdev; > # ifndef CONFIG_DM_KEYBOARD > int ret; > @@ -293,6 +351,7 @@ int stdio_add_devices(void) > ; > if (ret) > printf("%s: Video device failed (ret=%d)\n", __func__, ret); > +#endif /* !CONFIG_SYS_CONSOLE_IS_IN_ENV */ > #else > # if defined(CONFIG_LCD) > drv_lcd_init (); > -- Regards, Bin
diff --git a/common/stdio.c b/common/stdio.c index f99cfe7..b58b3c7 100644 --- a/common/stdio.c +++ b/common/stdio.c @@ -121,19 +121,76 @@ struct list_head* stdio_get_list(void) return &(devs.list); } +#ifdef CONFIG_DM_VIDEO +/** + * stdio_probe_device() - Find a device which provides the given stdio device + * + * This looks for a device of the given uclass which provides a particular + * stdio device. It is currently really only useful for UCLASS_VIDEO. + * + * Ultimately we want to be able to probe a device by its stdio name. At + * present devices register in their probe function (for video devices this + * is done in vidconsole_post_probe()) and we don't know what name they will + * use until they do so. + * TODO(sjg@chromium.org): We should be able to determine the name before + * probing, and probe the required device. + * + * @name: stdio device name (e.g. "vidconsole") + * id: Uclass ID of device to look for (e.g. UCLASS_VIDEO) + * @sdevp: Returns stdout device, if found, else NULL + * @return 0 if found, -ENOENT if no device found with that name, other -ve + * on other error + */ +static int stdio_probe_device(const char *name, enum uclass_id id, + struct stdio_dev **sdevp) +{ + struct stdio_dev *sdev; + struct udevice *dev; + int seq, ret; + + *sdevp = NULL; + seq = trailing_strtoln(name, NULL); + if (seq == -1) + ret = uclass_first_device_err(id, &dev); + else + ret = uclass_get_device_by_seq(id, seq, &dev); + if (ret) { + debug("No %s device for seq %d (%s)\n", uclass_get_name(id), + seq, name); + return ret; + } + /* The device should be be the last one registered */ + sdev = list_empty(&devs.list) ? NULL : + list_last_entry(&devs.list, struct stdio_dev, list); + if (!sdev || strcmp(sdev->name, name)) { + debug("Device '%s' did not register with stdio as '%s'\n", + dev->name, name); + return -ENOENT; + } + *sdevp = sdev; + + return 0; +} +#endif + struct stdio_dev* stdio_get_by_name(const char *name) { struct list_head *pos; - struct stdio_dev *dev; + struct stdio_dev *sdev; if(!name) return NULL; list_for_each(pos, &(devs.list)) { - dev = list_entry(pos, struct stdio_dev, list); - if(strcmp(dev->name, name) == 0) - return dev; + sdev = list_entry(pos, struct stdio_dev, list); + if (strcmp(sdev->name, name) == 0) + return sdev; } +#ifdef CONFIG_DM_VIDEO + if (!strncmp(name, "vidconsole", 10) && !strchr(name, ',') && + !stdio_probe_device(name, UCLASS_VIDEO, &sdev)) + return sdev; +#endif return NULL; } @@ -282,6 +339,7 @@ int stdio_add_devices(void) #endif #endif #ifdef CONFIG_DM_VIDEO +#ifndef CONFIG_SYS_CONSOLE_IS_IN_ENV struct udevice *vdev; # ifndef CONFIG_DM_KEYBOARD int ret; @@ -293,6 +351,7 @@ int stdio_add_devices(void) ; if (ret) printf("%s: Video device failed (ret=%d)\n", __func__, ret); +#endif /* !CONFIG_SYS_CONSOLE_IS_IN_ENV */ #else # if defined(CONFIG_LCD) drv_lcd_init ();
At present all video devices are probed on start-up. It would be better to probe a device only when it is needed. This can happen if it is referenced in the stdout environment variable, for example. Add support for this by searching for a suitable device when needed, probing it, and finding the stdio device it creates. Signed-off-by: Simon Glass <sjg@chromium.org> --- common/stdio.c | 67 ++++++++++++++++++++++++++++++++++++++++++++++++++++++---- 1 file changed, 63 insertions(+), 4 deletions(-)