From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 9BC7EC433EF for ; Tue, 23 Nov 2021 08:13:06 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S231743AbhKWIQM (ORCPT ); Tue, 23 Nov 2021 03:16:12 -0500 Received: from fllv0015.ext.ti.com ([198.47.19.141]:51108 "EHLO fllv0015.ext.ti.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229504AbhKWIQJ (ORCPT ); Tue, 23 Nov 2021 03:16:09 -0500 Received: from fllv0034.itg.ti.com ([10.64.40.246]) by fllv0015.ext.ti.com (8.15.2/8.15.2) with ESMTP id 1AN8CiV0018369; Tue, 23 Nov 2021 02:12:44 -0600 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=ti.com; s=ti-com-17Q1; t=1637655164; bh=67aIcOkswqKyrdq+H++ZQwtZJ3cXkK9R7dfy3beKjOU=; h=From:To:CC:Subject:Date:In-Reply-To:References; b=TMIKs8kbol1j5aZo0E3JOldXLmOnfnvWDiXxFJcvAEGbRzPQuM1AFsAqLeZP1mdAR 1kwOmpAnEXIkOr1rPmPLwGrtw4HSYiJpBSrCSKegrp3z9dmR7fhCCMI8F7q6PUxUI5 qQdeYkAhumGVZEhpDTpvxox1sS/Ut1+fCtouFpAQ= Received: from DLEE108.ent.ti.com (dlee108.ent.ti.com [157.170.170.38]) by fllv0034.itg.ti.com (8.15.2/8.15.2) with ESMTPS id 1AN8CijD017209 (version=TLSv1.2 cipher=AES256-GCM-SHA384 bits=256 verify=FAIL); Tue, 23 Nov 2021 02:12:44 -0600 Received: from DLEE113.ent.ti.com (157.170.170.24) by DLEE108.ent.ti.com (157.170.170.38) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_128_CBC_SHA256_P256) id 15.1.2308.14; Tue, 23 Nov 2021 02:12:43 -0600 Received: from lelv0326.itg.ti.com (10.180.67.84) by DLEE113.ent.ti.com (157.170.170.24) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_128_CBC_SHA256_P256) id 15.1.2308.14 via Frontend Transport; Tue, 23 Nov 2021 02:12:43 -0600 Received: from gsaswath-HP-ProBook-640-G5.dal.design.ti.com (ileax41-snat.itg.ti.com [10.172.224.153]) by lelv0326.itg.ti.com (8.15.2/8.15.2) with ESMTP id 1AN8CNe1101399; Tue, 23 Nov 2021 02:12:39 -0600 From: Aswath Govindraju CC: Vignesh Raghavendra , Nishanth Menon , Aswath Govindraju , Peter Rosin , Rob Herring , Wolfgang Grandegger , Marc Kleine-Budde , Kishon Vijay Abraham I , Vinod Koul , , , , Subject: [PATCH RFC v3 3/4] mux: Add support for reading mux enable state from DT Date: Tue, 23 Nov 2021 13:42:20 +0530 Message-ID: <20211123081222.27979-4-a-govindraju@ti.com> X-Mailer: git-send-email 2.17.1 In-Reply-To: <20211123081222.27979-1-a-govindraju@ti.com> References: <20211123081222.27979-1-a-govindraju@ti.com> MIME-Version: 1.0 Content-Type: text/plain X-EXCLAIMER-MD-CONFIG: e1e8a2fd-e40a-4ac6-ac9b-f7e9cc9ee180 To: unlisted-recipients:; (no To-header on input) Precedence: bulk List-ID: X-Mailing-List: devicetree@vger.kernel.org In some cases, we might need to provide the state of the mux to be set for the operation of a given peripheral. Therefore, pass this information using the second argument of the mux-controls property. Signed-off-by: Aswath Govindraju --- drivers/mux/core.c | 146 ++++++++++++++++++++++++++++++++++- include/linux/mux/consumer.h | 19 ++++- include/linux/mux/driver.h | 13 ++++ 3 files changed, 173 insertions(+), 5 deletions(-) diff --git a/drivers/mux/core.c b/drivers/mux/core.c index 22f4709768d1..9622b98f9818 100644 --- a/drivers/mux/core.c +++ b/drivers/mux/core.c @@ -370,6 +370,29 @@ int mux_control_select_delay(struct mux_control *mux, unsigned int state, } EXPORT_SYMBOL_GPL(mux_control_select_delay); +/** + * mux_state_select_delay() - Select the enable state in mux-state + * @mux: The mux-state to request a change of state from. + * @delay_us: The time to delay (in microseconds) if the mux state is changed. + * + * On successfully selecting the enable state, it will be locked until + * there is a call to mux_state_deselect(). If the mux-control is already + * selected when mux_state_select() is called, the caller will be blocked + * until mux_state_deselect() is called (by someone else). + * + * Therefore, make sure to call mux_state_deselect() when the operation is + * complete and the mux-control is free for others to use, but do not call + * mux_state_deselect() if mux_state_select() fails. + * + * Return: 0 when the mux-state has the enable state or a negative + * errno on error. + */ +int mux_state_select_delay(struct mux_state *mux, unsigned int delay_us) +{ + return mux_control_select_delay(mux->mux, mux->enable_state, delay_us); +} +EXPORT_SYMBOL_GPL(mux_state_select_delay); + /** * mux_control_try_select_delay() - Try to select the given multiplexer state. * @mux: The mux-control to request a change of state from. @@ -405,6 +428,27 @@ int mux_control_try_select_delay(struct mux_control *mux, unsigned int state, } EXPORT_SYMBOL_GPL(mux_control_try_select_delay); +/** + * mux_state_try_select_delay() - Try to select the multiplexer enable state. + * @mux: The mux-control to request a change of state from. + * @delay_us: The time to delay (in microseconds) if the mux state is changed. + * + * On successfully selecting the enable state, it will be locked until + * mux_state_deselect() called. + * + * Therefore, make sure to call mux_state_deselect() when the operation is + * complete and the mux-control is free for others to use, but do not call + * mux_state_deselect() if mux_state_try_select() fails. + * + * Return: 0 when the mux-control state has the requested state or a negative + * errno on error. Specifically -EBUSY if the mux-control is contended. + */ +int mux_state_try_select_delay(struct mux_state *mux, unsigned int delay_us) +{ + return mux_control_try_select_delay(mux->mux, mux->enable_state, delay_us); +} +EXPORT_SYMBOL_GPL(mux_state_try_select_delay); + /** * mux_control_deselect() - Deselect the previously selected multiplexer state. * @mux: The mux-control to deselect. @@ -431,6 +475,24 @@ int mux_control_deselect(struct mux_control *mux) } EXPORT_SYMBOL_GPL(mux_control_deselect); +/** + * mux_state_deselect() - Deselect the previously selected multiplexer state. + * @mux: The mux-state to deselect. + * + * It is required that a single call is made to mux_state_deselect() for + * each and every successful call made to either of mux_state_select() or + * mux_state_try_select(). + * + * Return: 0 on success and a negative errno on error. An error can only + * occur if the mux has an idle state. Note that even if an error occurs, the + * mux-control is unlocked and is thus free for the next access. + */ +int mux_state_deselect(struct mux_state *mux) +{ + return mux_control_deselect(mux->mux); +} +EXPORT_SYMBOL_GPL(mux_state_deselect); + /* Note this function returns a reference to the mux_chip dev. */ static struct mux_chip *of_find_mux_chip_by_node(struct device_node *np) { @@ -442,13 +504,15 @@ static struct mux_chip *of_find_mux_chip_by_node(struct device_node *np) } /** - * mux_control_get() - Get the mux-control for a device. + * mux_get() - Get the mux-control for a device. * @dev: The device that needs a mux-control. * @mux_name: The name identifying the mux-control. + * @enable_state: The variable to store the enable state for the requested device * * Return: A pointer to the mux-control, or an ERR_PTR with a negative errno. */ -struct mux_control *mux_control_get(struct device *dev, const char *mux_name) +static struct mux_control *mux_get(struct device *dev, const char *mux_name, + unsigned int *enable_state) { struct device_node *np = dev->of_node; struct of_phandle_args args; @@ -481,8 +545,7 @@ struct mux_control *mux_control_get(struct device *dev, const char *mux_name) if (!mux_chip) return ERR_PTR(-EPROBE_DEFER); - if (args.args_count > 1 || - (!args.args_count && (mux_chip->controllers > 1))) { + if (!args.args_count && mux_chip->controllers > 1) { dev_err(dev, "%pOF: wrong #mux-control-cells for %pOF\n", np, args.np); put_device(&mux_chip->dev); @@ -500,8 +563,25 @@ struct mux_control *mux_control_get(struct device *dev, const char *mux_name) return ERR_PTR(-EINVAL); } + if (args.args_count == 2) + *enable_state = args.args[1]; + return &mux_chip->mux[controller]; } + +/** + * mux_control_get() - Get the mux-control for a device. + * @dev: The device that needs a mux-control. + * @mux_name: The name identifying the mux-control. + * + * Return: A pointer to the mux-control, or an ERR_PTR with a negative errno. + */ +struct mux_control *mux_control_get(struct device *dev, const char *mux_name) +{ + int state; + + return mux_get(dev, mux_name, &state); +} EXPORT_SYMBOL_GPL(mux_control_get); /** @@ -523,6 +603,26 @@ static void devm_mux_control_release(struct device *dev, void *res) mux_control_put(mux); } +/** + * mux_state_put() - Put away the mux-state for good. + * @mux: The mux-state to put away. + * + * mux_control_put() reverses the effects of mux_control_get(). + */ +void mux_state_put(struct mux_state *mux_state) +{ + mux_control_put(mux_state->mux); + kfree(mux_state); +} +EXPORT_SYMBOL_GPL(mux_state_put); + +static void devm_mux_state_release(struct device *dev, void *res) +{ + struct mux_state *mux = *(struct mux_state **)res; + + mux_state_put(mux); +} + /** * devm_mux_control_get() - Get the mux-control for a device, with resource * management. @@ -553,6 +653,44 @@ struct mux_control *devm_mux_control_get(struct device *dev, } EXPORT_SYMBOL_GPL(devm_mux_control_get); +/** + * devm_mux_state_get() - Get the mux-state for a device, with resource + * management. + * @dev: The device that needs a mux-control. + * @mux_name: The name identifying the mux-control. + * + * Return: Pointer to the mux-state, or an ERR_PTR with a negative errno. + */ +struct mux_state *devm_mux_state_get(struct device *dev, + const char *mux_name) +{ + struct mux_state **ptr, *mux_state; + struct mux_control *mux_ctrl; + int enable_state; + + mux_state = devm_kzalloc(dev, sizeof(struct mux_state), GFP_KERNEL); + if (!mux_state) + return ERR_PTR(-ENOMEM); + + ptr = devres_alloc(devm_mux_state_release, sizeof(*ptr), GFP_KERNEL); + if (!ptr) + return ERR_PTR(-ENOMEM); + + mux_ctrl = mux_get(dev, mux_name, &enable_state); + if (IS_ERR(mux_ctrl)) { + devres_free(ptr); + return (struct mux_state *)mux_ctrl; + } + + mux_state->mux = mux_ctrl; + mux_state->enable_state = enable_state; + *ptr = mux_state; + devres_add(dev, ptr); + + return mux_state; +} +EXPORT_SYMBOL_GPL(devm_mux_state_get); + /* * Using subsys_initcall instead of module_init here to try to ensure - for * the non-modular case - that the subsystem is initialized when mux consumers diff --git a/include/linux/mux/consumer.h b/include/linux/mux/consumer.h index 7a09b040ac39..d0f3242e148d 100644 --- a/include/linux/mux/consumer.h +++ b/include/linux/mux/consumer.h @@ -14,33 +14,50 @@ struct device; struct mux_control; +struct mux_state; unsigned int mux_control_states(struct mux_control *mux); int __must_check mux_control_select_delay(struct mux_control *mux, unsigned int state, unsigned int delay_us); +int __must_check mux_state_select_delay(struct mux_state *mux, + unsigned int delay_us); int __must_check mux_control_try_select_delay(struct mux_control *mux, unsigned int state, unsigned int delay_us); - +int __must_check mux_state_try_select_delay(struct mux_state *mux, + unsigned int delay_us); static inline int __must_check mux_control_select(struct mux_control *mux, unsigned int state) { return mux_control_select_delay(mux, state, 0); } +static inline int __must_check mux_state_select(struct mux_state *mux) +{ + return mux_state_select_delay(mux, 0); +} static inline int __must_check mux_control_try_select(struct mux_control *mux, unsigned int state) { return mux_control_try_select_delay(mux, state, 0); } +static inline int __must_check mux_state_try_select(struct mux_state *mux) +{ + return mux_state_try_select_delay(mux, 0); +} + int mux_control_deselect(struct mux_control *mux); +int mux_state_deselect(struct mux_state *mux); struct mux_control *mux_control_get(struct device *dev, const char *mux_name); void mux_control_put(struct mux_control *mux); +void mux_state_put(struct mux_state *mux); struct mux_control *devm_mux_control_get(struct device *dev, const char *mux_name); +struct mux_state *devm_mux_state_get(struct device *dev, + const char *mux_name); #endif /* _LINUX_MUX_CONSUMER_H */ diff --git a/include/linux/mux/driver.h b/include/linux/mux/driver.h index 18824064f8c0..c7236f307fbd 100644 --- a/include/linux/mux/driver.h +++ b/include/linux/mux/driver.h @@ -53,6 +53,19 @@ struct mux_control { ktime_t last_change; }; +/** + * struct mux_state - Represents a mux controller specific to a given device + * @mux: Pointer to a mux controller + * @enable_state State of the mux to be set for enabling a device + * + * This structure is specific to a device that acquires it and has information + * specific to the device. + */ +struct mux_state { + struct mux_control *mux; + unsigned int enable_state; +}; + /** * struct mux_chip - Represents a chip holding mux controllers. * @controllers: Number of mux controllers handled by the chip. -- 2.17.1