diff options
author | Sean Anderson <seanga2@gmail.com> | 2020-06-24 13:41:12 +0300 |
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committer | Andes <uboot@andestech.com> | 2020-07-01 10:01:21 +0300 |
commit | 4a3390f1d3b71f0645eb281176f00cd0d5ac2dcb (patch) | |
tree | 373138fe61aea783757084532eb3c7c3111ee285 /drivers/core/simple-pm-bus.c | |
parent | f9c7d4f99f51ac9c1cf513111c21395f93d2dd53 (diff) | |
download | u-boot-4a3390f1d3b71f0645eb281176f00cd0d5ac2dcb.tar.xz |
dm: Add support for simple-pm-bus
This type of bus is used in Linux to designate buses which have power
domains and/or clocks which need to be enabled before their child devices
can be used. Because power domains are automatically enabled before probing
in U-Boot, we just need to enable any clocks present.
Signed-off-by: Sean Anderson <seanga2@gmail.com>
Reviewed-by: Simon Glass <sjg@chromium.org>
Diffstat (limited to 'drivers/core/simple-pm-bus.c')
-rw-r--r-- | drivers/core/simple-pm-bus.c | 56 |
1 files changed, 56 insertions, 0 deletions
diff --git a/drivers/core/simple-pm-bus.c b/drivers/core/simple-pm-bus.c new file mode 100644 index 0000000000..51dc9b206f --- /dev/null +++ b/drivers/core/simple-pm-bus.c @@ -0,0 +1,56 @@ +// SPDX-License-Identifier: GPL-2.0+ +/* + * Copyright (C) 2020 Sean Anderson <seanga2@gmail.com> + */ + +#include <common.h> +#include <clk.h> +#include <dm.h> + +/* + * Power domains are taken care of by driver_probe, so we just have to enable + * clocks + */ +static int simple_pm_bus_probe(struct udevice *dev) +{ + int ret; + struct clk_bulk *bulk = dev_get_priv(dev); + + ret = clk_get_bulk(dev, bulk); + if (ret) + return ret; + + ret = clk_enable_bulk(bulk); + if (ret && ret != -ENOSYS && ret != -ENOTSUPP) { + clk_release_bulk(bulk); + return ret; + } + return 0; +} + +static int simple_pm_bus_remove(struct udevice *dev) +{ + int ret; + struct clk_bulk *bulk = dev_get_priv(dev); + + ret = clk_release_bulk(bulk); + if (ret && ret != -ENOSYS && ret != -ENOTSUPP) + return ret; + else + return 0; +} + +static const struct udevice_id simple_pm_bus_ids[] = { + { .compatible = "simple-pm-bus" }, + { } +}; + +U_BOOT_DRIVER(simple_pm_bus_drv) = { + .name = "simple_pm_bus", + .id = UCLASS_SIMPLE_BUS, + .of_match = simple_pm_bus_ids, + .probe = simple_pm_bus_probe, + .remove = simple_pm_bus_remove, + .priv_auto_alloc_size = sizeof(struct clk_bulk), + .flags = DM_FLAG_PRE_RELOC, +}; |