From 0c28233903b5af9a7f41b3200993cfa197b35719 Mon Sep 17 00:00:00 2001 From: Neil Armstrong Date: Tue, 3 Apr 2018 11:40:50 +0200 Subject: 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 Reviewed-by: Simon Glass --- drivers/reset/reset-uclass.c | 60 +++++++++++++++++++++++++++ include/reset.h | 99 ++++++++++++++++++++++++++++++++++++++++++++ 2 files changed, 159 insertions(+) diff --git a/drivers/reset/reset-uclass.c b/drivers/reset/reset-uclass.c index 307a29705f..9a5c9c91b9 100644 --- a/drivers/reset/reset-uclass.c +++ b/drivers/reset/reset-uclass.c @@ -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; diff --git a/include/reset.h b/include/reset.h index 7185ade7ac..d38f1765ec 100644 --- a/include/reset.h +++ b/include/reset.h @@ -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 -- cgit