It is easy to forget to call qcom_smem_state_put() after a qcom_smem_state_get(). Introduce a devm_qcom_smem_state_get() helper function that automates this so that qcom_smem_state_put() is automatically called when a device is removed. Signed-off-by: Stephan Gerhold <stephan@xxxxxxxxxxx> --- I use this in my WIP bam-dmux driver, so it might simplify coordination later if we can somehow get this in for 5.14 (if it isn't too late yet). Similar code can be found in clk-devres.c for example: https://elixir.bootlin.com/linux/v5.13-rc6/source/drivers/clk/clk-devres.c#L7 --- drivers/soc/qcom/smem_state.c | 36 +++++++++++++++++++++++++++++ include/linux/soc/qcom/smem_state.h | 7 ++++++ 2 files changed, 43 insertions(+) diff --git a/drivers/soc/qcom/smem_state.c b/drivers/soc/qcom/smem_state.c index d2b558438deb..31faf4aa868e 100644 --- a/drivers/soc/qcom/smem_state.c +++ b/drivers/soc/qcom/smem_state.c @@ -151,6 +151,42 @@ void qcom_smem_state_put(struct qcom_smem_state *state) } EXPORT_SYMBOL_GPL(qcom_smem_state_put); +static void devm_qcom_smem_state_release(struct device *dev, void *res) +{ + qcom_smem_state_put(*(struct qcom_smem_state **)res); +} + +/** + * devm_qcom_smem_state_get() - acquire handle to a devres managed state + * @dev: client device pointer + * @con_id: name of the state to lookup + * @bit: flags from the state reference, indicating which bit's affected + * + * Returns handle to the state, or ERR_PTR(). qcom_smem_state_put() is called + * automatically when @dev is removed. + */ +struct qcom_smem_state *devm_qcom_smem_state_get(struct device *dev, + const char *con_id, + unsigned *bit) +{ + struct qcom_smem_state **ptr, *state; + + ptr = devres_alloc(devm_qcom_smem_state_release, sizeof(*ptr), GFP_KERNEL); + if (!ptr) + return ERR_PTR(-ENOMEM); + + state = qcom_smem_state_get(dev, con_id, bit); + if (!IS_ERR(state)) { + *ptr = state; + devres_add(dev, ptr); + } else { + devres_free(ptr); + } + + return state; +} +EXPORT_SYMBOL_GPL(devm_qcom_smem_state_get); + /** * qcom_smem_state_register() - register a new state * @of_node: of_node used for matching client lookups diff --git a/include/linux/soc/qcom/smem_state.h b/include/linux/soc/qcom/smem_state.h index 63ad8cddad14..17c56a50302f 100644 --- a/include/linux/soc/qcom/smem_state.h +++ b/include/linux/soc/qcom/smem_state.h @@ -14,6 +14,7 @@ struct qcom_smem_state_ops { #ifdef CONFIG_QCOM_SMEM_STATE struct qcom_smem_state *qcom_smem_state_get(struct device *dev, const char *con_id, unsigned *bit); +struct qcom_smem_state *devm_qcom_smem_state_get(struct device *dev, const char *con_id, unsigned *bit); void qcom_smem_state_put(struct qcom_smem_state *); int qcom_smem_state_update_bits(struct qcom_smem_state *state, u32 mask, u32 value); @@ -29,6 +30,12 @@ static inline struct qcom_smem_state *qcom_smem_state_get(struct device *dev, return ERR_PTR(-EINVAL); } +static inline struct qcom_smem_state *devm_qcom_smem_state_get(struct device *dev, + const char *con_id, unsigned *bit) +{ + return ERR_PTR(-EINVAL); +} + static inline void qcom_smem_state_put(struct qcom_smem_state *state) { } -- 2.32.0
