Hi Marco, On Fri, Aug 09, 2019 at 02:16:06PM +0200, Marco Felsch wrote: > On 19-05-16 19:51, Laurent Pinchart wrote: > > On Tue, May 14, 2019 at 03:20:04PM -0300, Mauro Carvalho Chehab wrote: > >> Em Mon, 6 May 2019 12:10:41 +0200 Hans Verkuil escreveu: > >>> On 4/15/19 2:44 PM, Marco Felsch wrote: > >>>> The patch adds the initial connector parsing code, so we can move from a > >>>> driver specific parsing code to a generic one. Currently only the > >>>> generic fields and the analog-connector specific fields are parsed. Parsing > >>>> the other connector specific fields can be added by a simple callbacks. > >>>> > >>>> Signed-off-by: Marco Felsch <m.felsch@xxxxxxxxxxxxxx> > >>>> Reviewed-by: Jacopo Mondi <jacopo@xxxxxxxxxx> > >>>> --- > >>>> [1] https://patchwork.kernel.org/cover/10794703/ > >>>> > >>>> v6: > >>>> - use 'unsigned int' count var > >>>> - fix comment and style issues > >>>> - place '/* fall through */' to correct places > >>>> - fix error handling and cleanup by releasing fwnode > >>>> - drop vga and dvi parsing support as those connectors are rarely used > >>>> these days > >>>> > >>>> v5: > >>>> - s/strlcpy/strscpy/ > >>>> > >>>> v2-v4: > >>>> - nothing since the patch was squashed from series [1] into this > >>>> series. > >>>> > >>>> drivers/media/v4l2-core/v4l2-fwnode.c | 111 ++++++++++++++++++++++++++ > >>>> include/media/v4l2-fwnode.h | 16 ++++ > >>>> 2 files changed, 127 insertions(+) > >>>> > >>>> diff --git a/drivers/media/v4l2-core/v4l2-fwnode.c b/drivers/media/v4l2-core/v4l2-fwnode.c > >>>> index 20571846e636..f1cca95c8fef 100644 > >>>> --- a/drivers/media/v4l2-core/v4l2-fwnode.c > >>>> +++ b/drivers/media/v4l2-core/v4l2-fwnode.c > >>>> @@ -592,6 +592,117 @@ void v4l2_fwnode_put_link(struct v4l2_fwnode_link *link) > >>>> } > >>>> EXPORT_SYMBOL_GPL(v4l2_fwnode_put_link); > >>>> > >>>> +static const struct v4l2_fwnode_connector_conv { > >>>> + enum v4l2_connector_type type; > >>>> + const char *name; > > > > Maybe compatible instead of name ? > > Okay, I can change that. > > >>>> +} connectors[] = { > >>>> + { > >>>> + .type = V4L2_CON_COMPOSITE, > >>>> + .name = "composite-video-connector", > >>>> + }, { > >>>> + .type = V4L2_CON_SVIDEO, > >>>> + .name = "svideo-connector", > >>>> + }, { > >>>> + .type = V4L2_CON_HDMI, > >>>> + .name = "hdmi-connector", > >>>> + }, > >>>> +}; > >>>> + > >>>> +static enum v4l2_connector_type > >>>> +v4l2_fwnode_string_to_connector_type(const char *con_str) > >>>> +{ > >>>> + unsigned int i; > >>>> + > >>>> + for (i = 0; i < ARRAY_SIZE(connectors); i++) > >>>> + if (!strcmp(con_str, connectors[i].name)) > >>>> + return connectors[i].type; > >>>> + > >>>> + /* no valid connector found */ > > > > The usual comment style in this file is to start with a capital letter > > and end sentences with a period. I would however drop this comment, it's > > not very useful. The other comments should be updated accordingly. > > I will change my comments and drop this one. > > >>>> + return V4L2_CON_UNKNOWN; > >>>> +} > >>>> + > >>>> +static int > >>>> +v4l2_fwnode_connector_parse_analog(struct fwnode_handle *fwnode, > >>>> + struct v4l2_fwnode_connector *vc) > >>>> +{ > >>>> + u32 tvnorms; > >>>> + int ret; > >>>> + > >>>> + ret = fwnode_property_read_u32(fwnode, "tvnorms", &tvnorms); > >>>> + > >>>> + /* tvnorms is optional */ > >>>> + vc->connector.analog.supported_tvnorms = ret ? V4L2_STD_ALL : tvnorms; > >>>> + > >>>> + return 0; > >>>> +} > >>>> + > > > > Please document all exported functions with kerneldoc. > > It is documented within the header file. To be aligned with the other > functions I wouldn't change that. It's not your fault, but this policy REALLY makes review painful and is EXTREMELY annoying. > >>>> +int v4l2_fwnode_parse_connector(struct fwnode_handle *__fwnode, > >>>> + struct v4l2_fwnode_connector *connector) > >>>> +{ > >>>> + struct fwnode_handle *fwnode; > >>>> + struct fwnode_endpoint __ep; > >>>> + const char *c_type_str, *label; > >>>> + int ret; > >>>> + > >>>> + memset(connector, 0, sizeof(*connector)); > >>>> + > >>>> + fwnode = fwnode_graph_get_remote_port_parent(__fwnode); > > > > I would rename the argument __fwnode to fwnode, and rename the fwnode > > variable to remote (or similar) to make this clearer. > > Okay. > > >>>> + if (!fwnode) > >>>> + return -EINVAL; > > > > Is EINVAL the right error here ? Wouldn't it be useful for the caller to > > differentiate between unconnected connector nodes and invalid ones ? > > Yes it would. Should I return ENOLINK instead? Good idea. > >>>> + > >>>> + /* parse all common properties first */ > >>>> + /* connector-type is stored within the compatible string */ > >>>> + ret = fwnode_property_read_string(fwnode, "compatible", &c_type_str); > > > > Prefixing or postfixing names with types is usually frowned upon. You > > could rename this to type_name for instance. > > Okay. > > >>>> + if (ret) { > >>>> + fwnode_handle_put(fwnode); > >>>> + return -EINVAL; > >>>> + } > >>>> + > >>>> + connector->type = v4l2_fwnode_string_to_connector_type(c_type_str); > >>>> + > >>>> + fwnode_graph_parse_endpoint(__fwnode, &__ep); > >>>> + connector->remote_port = __ep.port; > >>>> + connector->remote_id = __ep.id; > >>>> + > >>>> + ret = fwnode_property_read_string(fwnode, "label", &label); > >>>> + if (!ret) { > >>>> + /* ensure label doesn't exceed V4L2_CONNECTOR_MAX_LABEL size */ > >>>> + strscpy(connector->label, label, V4L2_CONNECTOR_MAX_LABEL); > >>>> + } else { > >>>> + /* > >>>> + * labels are optional, if none is given create one: > >>>> + * <connector-type-string>@port<endpoint_port>/ep<endpoint_id> > >>>> + */ > >>>> + snprintf(connector->label, V4L2_CONNECTOR_MAX_LABEL, > >>>> + "%s@port%u/ep%u", c_type_str, connector->remote_port, > >>>> + connector->remote_id); > > > > Should we really try to create labels when none is available ? If so > > this needs much more careful thoughts, we need to think about what the > > label will be used for, and create a good naming scheme accordingly. If > > the label will be displayed to the end-user I don't think the above name > > would be very useful, it would be best to leave it empty and let > > applications create a name based on the connector type and other > > information they have at their disposal. > > Hm.. I don't have a strong opinion on that. If the others are with you I > will leave it empty. > > >>>> + } > >>>> + > >>>> + /* now parse the connector specific properties */ > >>>> + switch (connector->type) { > >>>> + case V4L2_CON_COMPOSITE: > >>>> + /* fall through */ > > > > I don't think you need a fall-through comment when the two cases are > > adjacent with no line in-between. > > Hm.. I don't know the compiler behaviour. According the official > gcc documentation [1] I would not leave that. Not leave the fall-through comment, and thus remove it ? :-) I really think it's not needed (otherwise imagine how the big switch-case in v4l2-ctrls.c would look like for instance). > [1] https://gcc.gnu.org/onlinedocs/gcc/Warning-Options.html > > >>>> + case V4L2_CON_SVIDEO: > >>>> + ret = v4l2_fwnode_connector_parse_analog(fwnode, connector); > >>>> + break; > >>>> + case V4L2_CON_HDMI: > >>>> + pr_warn("Connector specific parsing is currently not supported for %s\n", > >>>> + c_type_str); > >>> > >>> Why warn? Just drop this. > >> > >> good point. I would prefer to have some warning here, in order to warn a > >> developer that might be using it that this part of the code would require > >> some change. > >> > >> perhaps pr_warn_once()? > >> > >>>> + ret = 0; > >>>> + break; > > > > If it's not supported we should warn and return an error. Otherwise we > > should be silent and return success. Combining a warning with success > > isn't a good idea, this is either a normal case or an error, not both. > > The generic part still applies and is valid. That was the reason why I > did return success. But the HDMI-specific part won't work, so the code will likely not operate correctly. I'd rather make it an error to for developers using HDMI connectors to fix it. > >>>> + case V4L2_CON_UNKNOWN: > >>>> + /* fall through */ > >>>> + default: > >>>> + pr_err("Unknown connector type\n"); > >>>> + ret = -EINVAL; > >>>> + }; > >>>> + > >>>> + fwnode_handle_put(fwnode); > >>>> + > >>>> + return ret; > >>>> +} > >>>> +EXPORT_SYMBOL_GPL(v4l2_fwnode_parse_connector); > >>>> + > >>>> static int > >>>> v4l2_async_notifier_fwnode_parse_endpoint(struct device *dev, > >>>> struct v4l2_async_notifier *notifier, > >>>> diff --git a/include/media/v4l2-fwnode.h b/include/media/v4l2-fwnode.h > >>>> index f4df1b95c5ef..e072f2915ddb 100644 > >>>> --- a/include/media/v4l2-fwnode.h > >>>> +++ b/include/media/v4l2-fwnode.h > >>>> @@ -269,6 +269,22 @@ int v4l2_fwnode_parse_link(struct fwnode_handle *fwnode, > >>>> */ > >>>> void v4l2_fwnode_put_link(struct v4l2_fwnode_link *link); > >>>> > > > > And I see here that the function is documented. One more reason to move > > kerneldoc to the .c files... > > Please check my comment above. I know, it's not your fault, I was complaining about the state of the universe in general :-) > >>>> +/** > >>>> + * v4l2_fwnode_parse_connector() - parse the connector on endpoint > >>>> + * @fwnode: pointer to the endpoint's fwnode handle where the connector is > >>>> + * connected to > > > > This is very unclear, I would interpret that as the remote endpoint, not > > the local endpoint. Could you please try to clarify the documentation ? > > Hm.. I have no good idea how I should describe it.. > > """ > The device (local) endpoint fwnode handle on which the connector is > connected to using the remote-enpoint property. > """ > > >>>> + * @connector: pointer to the V4L2 fwnode connector data structure > >>>> + * > >>>> + * Fill the connector data structure with the connector type, label and the > >>>> + * endpoint id and port where the connector belongs to. If no label is present > >>>> + * a unique one will be created. Labels with more than 40 characters are cut. > >>>> + * > >>>> + * Return: %0 on success or a negative error code on failure: > >>>> + * %-EINVAL on parsing failure > >>>> + */ > >>>> +int v4l2_fwnode_parse_connector(struct fwnode_handle *fwnode, > >>>> + struct v4l2_fwnode_connector *connector); > >>>> + > >>>> /** > >>>> * typedef parse_endpoint_func - Driver's callback function to be called on > >>>> * each V4L2 fwnode endpoint. -- Regards, Laurent Pinchart
