reset: Add get/assert/deassert/release for bulk of reset signals

This patch adds a "bulk" API to the reset API in order to get/deassert/
assert/release a group of reset signals associated with a device.

This bulk API will avoid adding a copy of the same code to manage
a group of reset signals in drivers.

Signed-off-by: Neil Armstrong <narmstrong@baylibre.com>
Reviewed-by: Simon Glass <sjg@chromium.org>
This commit is contained in:
Neil Armstrong 2018-04-03 11:40:50 +02:00 committed by Tom Rini
parent b71ac16063
commit 0c28233903
2 changed files with 159 additions and 0 deletions

View File

@ -81,6 +81,40 @@ int reset_get_by_index(struct udevice *dev, int index,
return 0;
}
int reset_get_bulk(struct udevice *dev, struct reset_ctl_bulk *bulk)
{
int i, ret, err, count;
bulk->count = 0;
count = dev_count_phandle_with_args(dev, "resets", "#reset-cells");
if (!count)
return 0;
bulk->resets = devm_kcalloc(dev, count, sizeof(struct reset_ctl),
GFP_KERNEL);
if (!bulk->resets)
return -ENOMEM;
for (i = 0; i < count; i++) {
ret = reset_get_by_index(dev, i, &bulk->resets[i]);
if (ret < 0)
goto bulk_get_err;
++bulk->count;
}
return 0;
bulk_get_err:
err = reset_release_all(bulk->resets, bulk->count);
if (err)
debug("%s: could release all resets for %p\n",
__func__, dev);
return ret;
}
int reset_get_by_name(struct udevice *dev, const char *name,
struct reset_ctl *reset_ctl)
{
@ -126,6 +160,19 @@ int reset_assert(struct reset_ctl *reset_ctl)
return ops->rst_assert(reset_ctl);
}
int reset_assert_bulk(struct reset_ctl_bulk *bulk)
{
int i, ret;
for (i = 0; i < bulk->count; i++) {
ret = reset_assert(&bulk->resets[i]);
if (ret < 0)
return ret;
}
return 0;
}
int reset_deassert(struct reset_ctl *reset_ctl)
{
struct reset_ops *ops = reset_dev_ops(reset_ctl->dev);
@ -135,6 +182,19 @@ int reset_deassert(struct reset_ctl *reset_ctl)
return ops->rst_deassert(reset_ctl);
}
int reset_deassert_bulk(struct reset_ctl_bulk *bulk)
{
int i, ret;
for (i = 0; i < bulk->count; i++) {
ret = reset_deassert(&bulk->resets[i]);
if (ret < 0)
return ret;
}
return 0;
}
int reset_release_all(struct reset_ctl *reset_ctl, int count)
{
int i, ret;

View File

@ -60,6 +60,24 @@ struct reset_ctl {
unsigned long id;
};
/**
* struct reset_ctl_bulk - A handle to (allowing control of) a bulk of reset
* signals.
*
* Clients provide storage for the reset control bulk. The content of the
* structure is managed solely by the reset API. A reset control bulk struct is
* initialized by "get"ing the reset control bulk struct.
* The reset control bulk struct is passed to all other bulk reset APIs to apply
* the API to all the reset signals in the bulk struct.
*
* @resets: An array of reset signal handles handles.
* @count: The number of reset signal handles in the reset array.
*/
struct reset_ctl_bulk {
struct reset_ctl *resets;
unsigned int count;
};
#ifdef CONFIG_DM_RESET
/**
* reset_get_by_index - Get/request a reset signal by integer index.
@ -80,6 +98,22 @@ struct reset_ctl {
int reset_get_by_index(struct udevice *dev, int index,
struct reset_ctl *reset_ctl);
/**
* reset_get_bulk - Get/request all reset signals of a device.
*
* This looks up and requests all reset signals of the client device; each
* device is assumed to have n reset signals associated with it somehow,
* and this function finds and requests all of them in a separate structure.
* The mapping of client device reset signals indices to provider reset signals
* may be via device-tree properties, board-provided mapping tables, or some
* other mechanism.
*
* @dev: The client device.
* @bulk A pointer to a reset control bulk struct to initialize.
* @return 0 if OK, or a negative error code.
*/
int reset_get_bulk(struct udevice *dev, struct reset_ctl_bulk *bulk);
/**
* reset_get_by_name - Get/request a reset signal by name.
*
@ -131,6 +165,21 @@ int reset_free(struct reset_ctl *reset_ctl);
*/
int reset_assert(struct reset_ctl *reset_ctl);
/**
* reset_assert_bulk - Assert all reset signals in a reset control bulk struct.
*
* This function will assert the specified reset signals in a reset control
* bulk struct, thus resetting the affected HW module(s). Depending on the
* reset controller hardware, the reset signals will either stay asserted
* until reset_deassert_bulk() is called, or the hardware may autonomously
* clear the reset signals itself.
*
* @bulk: A reset control bulk struct that was previously successfully
* requested by reset_get_bulk().
* @return 0 if OK, or a negative error code.
*/
int reset_assert_bulk(struct reset_ctl_bulk *bulk);
/**
* reset_deassert - Deassert a reset signal.
*
@ -144,6 +193,20 @@ int reset_assert(struct reset_ctl *reset_ctl);
*/
int reset_deassert(struct reset_ctl *reset_ctl);
/**
* reset_deassert_bulk - Deassert all reset signals in a reset control bulk
* struct.
*
* This function will deassert the specified reset signals in a reset control
* bulk struct, thus releasing the affected HW modules() from reset, and
* allowing them to continue normal operation.
*
* @bulk: A reset control bulk struct that was previously successfully
* requested by reset_get_bulk().
* @return 0 if OK, or a negative error code.
*/
int reset_deassert_bulk(struct reset_ctl_bulk *bulk);
/**
* reset_release_all - Assert/Free an array of previously requested resets.
*
@ -156,6 +219,23 @@ int reset_deassert(struct reset_ctl *reset_ctl);
* @return 0 if OK, or a negative error code.
*/
int reset_release_all(struct reset_ctl *reset_ctl, int count);
/**
* reset_release_bulk - Assert/Free an array of previously requested reset
* signals in a reset control bulk struct.
*
* For each reset contained in the reset control bulk struct, this function
* will check if reset has been previously requested and then will assert
* and free it.
*
* @bulk: A reset control bulk struct that was previously successfully
* requested by reset_get_bulk().
* @return 0 if OK, or a negative error code.
*/
static inline int reset_release_bulk(struct reset_ctl_bulk *bulk)
{
return reset_release_all(bulk->resets, bulk->count);
}
#else
static inline int reset_get_by_index(struct udevice *dev, int index,
struct reset_ctl *reset_ctl)
@ -163,6 +243,11 @@ static inline int reset_get_by_index(struct udevice *dev, int index,
return -ENOTSUPP;
}
static inline int reset_get_bulk(struct udevice *dev, struct clk_bulk *bulk)
{
return -ENOTSUPP;
}
static inline int reset_get_by_name(struct udevice *dev, const char *name,
struct reset_ctl *reset_ctl)
{
@ -179,16 +264,30 @@ static inline int reset_assert(struct reset_ctl *reset_ctl)
return 0;
}
static inline int reset_assert_bulk(struct reset_ctl_bulk *bulk)
{
return 0;
}
static inline int reset_deassert(struct reset_ctl *reset_ctl)
{
return 0;
}
static inline int reset_deassert_bulk(struct reset_ctl_bulk *bulk)
{
return 0;
}
static inline int reset_release_all(struct reset_ctl *reset_ctl, int count)
{
return 0;
}
static inline int reset_release_bulk(struct clk_bulk *bulk)
{
return 0;
}
#endif
#endif