[RFC PATCH 3/3] OMAP: omap_device: Add a method to build an omap_device from a DT node
Kevin Hilman
khilman at ti.com
Thu Sep 1 19:40:39 EDT 2011
Benoit Cousson <b-cousson at ti.com> writes:
> Add a notifier called during device_add phase. If a of_node is present,
> retrieve the hwmod entry in order to populate propely the omap_device
> structure.
> For the moment the resource from the device-tree are overloaded.
> DT does not support named resource yet, and thus, most driver
> will not work without that information.
>
> Signed-off-by: Benoit Cousson <b-cousson at ti.com>
> Cc: Kevin Hilman <khilman at ti.com>
Nice, minor comment below...
> ---
> arch/arm/plat-omap/omap_device.c | 102 ++++++++++++++++++++++++++++++++++++++
> 1 files changed, 102 insertions(+), 0 deletions(-)
>
> diff --git a/arch/arm/plat-omap/omap_device.c b/arch/arm/plat-omap/omap_device.c
> index 70361f8..0ae9e7f 100644
> --- a/arch/arm/plat-omap/omap_device.c
> +++ b/arch/arm/plat-omap/omap_device.c
> @@ -85,6 +85,8 @@
> #include <linux/clk.h>
> #include <linux/clkdev.h>
> #include <linux/pm_runtime.h>
> +#include <linux/of_platform.h>
> +#include <linux/notifier.h>
>
> #include <plat/omap_device.h>
> #include <plat/omap_hwmod.h>
> @@ -94,6 +96,8 @@
> #define USE_WAKEUP_LAT 0
> #define IGNORE_WAKEUP_LAT 1
>
> +#define MAX_HWMOD_NAME_SIZE 32
> +
> static int omap_device_register(struct platform_device *pdev);
> static int omap_early_device_register(struct platform_device *pdev);
> static struct omap_device *omap_device_alloc(struct platform_device *pdev,
> @@ -354,6 +358,100 @@ static int _dt_get_property(const char *prop, int len, int index, char *output,
> return -ENODEV;
> }
>
> +static struct dev_pm_domain omap_device_pm_domain;
> +
> +/**
> + * omap_device_build_from_dt - build an omap_device with multiple hwmods
> + * @pdev_name: name of the platform_device driver to use
> + * @pdev_id: this platform_device's connection ID
> + * @oh: ptr to the single omap_hwmod that backs this omap_device
> + * @pdata: platform_data ptr to associate with the platform_device
> + * @pdata_len: amount of memory pointed to by @pdata
> + * @pm_lats: pointer to a omap_device_pm_latency array for this device
> + * @pm_lats_cnt: ARRAY_SIZE() of @pm_lats
> + * @is_early_device: should the device be registered as an early device or not
> + *
> + * Function for building an omap_device already registered from device-tree
> + *
> + * Returns 0 or PTR_ERR() on error.
> + */
> +static int omap_device_build_from_dt(struct platform_device *pdev)
> +{
> + struct omap_hwmod **hwmods;
> + struct omap_device *od;
> + struct omap_hwmod *oh;
> + char oh_name[MAX_HWMOD_NAME_SIZE];
> + const char *prop;
> + int oh_cnt, i, prop_len;
> + int ret = 0;
> +
> + prop = of_get_property(pdev->dev.of_node, "hwmods", &prop_len);
> + oh_cnt = _dt_count_property_string(prop, prop_len);
> + if (!oh_cnt || IS_ERR_VALUE(oh_cnt)) {
> + dev_warn(&pdev->dev, "No 'hwmods' to build omap_device\n");
> + return -ENODEV;
> + }
> +
> + hwmods = kzalloc(sizeof(struct omap_hwmod *) * oh_cnt, GFP_KERNEL);
> + if (!hwmods) {
> + ret = -ENOMEM;
> + goto odbfd_exit;
> + }
> +
> + for (i = 0; i < oh_cnt; i++) {
> + _dt_get_property(prop, prop_len, i, oh_name,
> + MAX_HWMOD_NAME_SIZE);
> +
> + oh = omap_hwmod_lookup(oh_name);
> + if (!oh) {
> + dev_err(&pdev->dev, "Cannot lookup hwmod '%s'\n",
> + oh_name);
> + ret = -EINVAL;
> + goto odbfd_exit1;
> + }
> + hwmods[i] = oh;
> + }
> +
> + od = omap_device_alloc(pdev, hwmods, oh_cnt, NULL, 0);
> + if (!od) {
> + dev_err(&pdev->dev, "Cannot allocate omap_device for :%s\n",
> + oh_name);
> + ret = PTR_ERR(od);
> + goto odbfd_exit1;
> + }
> +
> + if (of_get_property(pdev->dev.of_node, "no_idle_on_suspend", NULL))
> + omap_device_disable_idle_on_suspend(pdev);
> +
> + pdev->dev.pm_domain = &omap_device_pm_domain;
> +
> +odbfd_exit1:
> + kfree(hwmods);
> +odbfd_exit:
> + return ret;
> +}
> +
> +static int _omap_device_notifier_call(struct notifier_block *nb,
> + unsigned long event, void *dev)
> +{
> + struct platform_device *pdev = to_platform_device(dev);
> +
> + switch (event) {
> + case BUS_NOTIFY_ADD_DEVICE:
> + if (pdev->dev.of_node) {
> + dev_dbg(&pdev->dev, "add_device with DT bindings\n");
> + omap_device_build_from_dt(pdev);
> + }
> + break;
> +
> + case BUS_NOTIFY_DEL_DEVICE:
> + dev_dbg(&pdev->dev, "del_device\n");
Need a delete/cleanup here.
Looks like all all it needs to do is call omap_device_delete()?
Kevin
> + break;
> + }
> +
> + return NOTIFY_DONE;
> +}
> +
>
> /* Public functions for use by core code */
>
> @@ -1064,8 +1162,12 @@ struct device omap_device_parent = {
> .parent = &platform_bus,
> };
>
> +static struct notifier_block platform_nb;
> +
> static int __init omap_device_init(void)
> {
> + platform_nb.notifier_call = _omap_device_notifier_call;
> + bus_register_notifier(&platform_bus_type, &platform_nb);
> return device_register(&omap_device_parent);
> }
> core_initcall(omap_device_init);
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