Hi Simon, On Thu, Sep 07, 2023 at 06:23:05AM -0600, Simon Glass wrote: > Hi AKASHI, > > On Tue, 5 Sept 2023 at 20:41, AKASHI Takahiro > <takahiro.aka...@linaro.org> wrote: > > > > This DM-compliant driver deals with SCMI pinctrl protocol and presents > > gpio devices exposed by SCMI firmware (server). > > > > Signed-off-by: AKASHI Takahiro <takahiro.aka...@linaro.org> > > --- > > drivers/pinctrl/pinctrl-scmi.c | 544 ++++++++++++++++++++++++++++++++- > > 1 file changed, 539 insertions(+), 5 deletions(-) > > > > diff --git a/drivers/pinctrl/pinctrl-scmi.c b/drivers/pinctrl/pinctrl-scmi.c > > index 3ebdad57b86c..73d385bdbfcc 100644 > > --- a/drivers/pinctrl/pinctrl-scmi.c > > +++ b/drivers/pinctrl/pinctrl-scmi.c > > @@ -11,21 +11,20 @@ > > #include <malloc.h> > > #include <scmi_agent.h> > > #include <scmi_protocols.h> > > +#include <asm-generic/gpio.h> > > #include <dm/device_compat.h> > > +#include <dm/device-internal.h> > > +#include <dm/lists.h> > > #include <dm/pinctrl.h> > > > [..] > > > + > > +U_BOOT_DRIVER(scmi_gpio) = { > > + .name = "scmi_gpio", > > + .id = UCLASS_GPIO, > > + .of_match = scmi_gpio_ids, > > + .of_to_plat = scmi_gpio_probe, > > + .ops = &scmi_gpio_ops, > > + .plat_auto = sizeof(struct scmi_pinctrl_gpio_plat), > > +}; > > + > > +/** > > + * scmi_gpiochip_register - Create a pinctrl-controlled gpio device > > + * @parent: SCMI pinctrl device > > + * > > + * Create a pinctrl-controlled gpio device > > + * > > + * Return: 0 on success, error code on failure > > + */ > > +static int scmi_gpiochip_register(struct udevice *parent) > > +{ > > + ofnode node; > > + struct driver *drv; > > + struct udevice *gpio_dev; > > + int ret; > > + > > + /* TODO: recovery if failed */ > > + dev_for_each_subnode(node, parent) { > > + if (!ofnode_is_enabled(node)) > > + continue; > > Can we not rely on the normal driver model binding to bind these > devices? Why does it need to be done manually here?
First, please take a look at the cover letter. In this RFC, I basically assume two patterns of DT bindings, (A) and (B) in the cover letter (or sandbox's test.dts in patch#5). In (B), a DT node as a gpio device, which is essentially a child of pinctrl device, is located *under* a pinctrl device. It need to be probed manually as there is no implicit method to enumerate it as a DM device automatically. On the other hand, in (A), the same node can be put anywhere in a DT as it contains a "compatible" property to identify itself. So if we want to only support (A), scmi_gpiochip_register() and scmi_pinctrl_bind() are not necessary. Since there is no discussion about bindings for GPIO managed by SCMI pinctrl device yet on the kernel side, I have left two solutions in this RFC. Thanks, -Takakahiro Akashi > > + > > + if (!ofnode_read_prop(node, "gpio-controller", NULL)) > > + /* not a GPIO node */ > > + continue; > > + > > + drv = DM_DRIVER_GET(scmi_gpio); > > + if (!drv) { > > + dev_err(parent, "No gpio driver?\n"); > > + return -ENODEV; > > + } > > + > > + ret = device_bind(parent, drv, ofnode_get_name(node), NULL, > > + node, &gpio_dev); > > + if (ret) { > > + dev_err(parent, "failed to bind %s to gpio (%d)\n", > > + ofnode_get_name(node), ret); > > + return -ENODEV; > > + } > > + > > + return 0; > > + } > > + > > + return -ENODEV; > > +} > > + > > Regards, > Simon