From patchwork Mon Apr 6 15:58:04 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Kamel BOUHARA X-Patchwork-Id: 207969 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-9.8 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH, MAILING_LIST_MULTI, SIGNED_OFF_BY, SPF_HELO_NONE, SPF_PASS, URIBL_BLOCKED, USER_AGENT_GIT autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id ABB4DC2BA17 for ; Mon, 6 Apr 2020 15:58:29 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 6AF29248EA for ; Mon, 6 Apr 2020 15:58:29 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1729178AbgDFP63 (ORCPT ); Mon, 6 Apr 2020 11:58:29 -0400 Received: from relay1-d.mail.gandi.net ([217.70.183.193]:39715 "EHLO relay1-d.mail.gandi.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1728817AbgDFP62 (ORCPT ); Mon, 6 Apr 2020 11:58:28 -0400 X-Originating-IP: 78.193.40.249 Received: from localhost (unknown [78.193.40.249]) (Authenticated sender: kamel.bouhara@bootlin.com) by relay1-d.mail.gandi.net (Postfix) with ESMTPSA id C8941240004; Mon, 6 Apr 2020 15:58:24 +0000 (UTC) From: Kamel Bouhara To: Dmitry Torokhov , William Breathitt Gray , Rob Herring , Mark Rutland Cc: Nicolas Ferre , Alexandre Belloni , Ludovic Desroches , linux-arm-kernel@lists.infradead.org, Thomas Petazzoni , linux-input@vger.kernel.org, devicetree@vger.kernel.org, linux-kernel@vger.kernel.org, linux-iio@vger.kernel.org, Kamel Bouhara Subject: [PATCH 1/3] counter: add an inkernel API Date: Mon, 6 Apr 2020 17:58:04 +0200 Message-Id: <20200406155806.1295169-2-kamel.bouhara@bootlin.com> X-Mailer: git-send-email 2.25.0 In-Reply-To: <20200406155806.1295169-1-kamel.bouhara@bootlin.com> References: <20200406155806.1295169-1-kamel.bouhara@bootlin.com> MIME-Version: 1.0 Sender: linux-input-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-input@vger.kernel.org Currently, counter devices are exposed directly to user-space through a sysfs interface. However, there are situations where it might makes sense for another kernel driver to use a counter handled by the counter subsystem. An example is the implementation of an input driver for a rotary encoder that is connected to hardware counters handled by the counter subsystem. This is very much like what happens with IIO subsystem, where ADC channels are directly accessible by user-space through sysfs, or can be used through the IIO in-kernel API by other kernel drivers, such as the adc-keys input keyboard driver. The proposed API is fairly simple: - devm_counter_get() allows a driver to get a reference to a counter device. From a Device Tree point of view, a counter-phandle property allows to indicate which counter device should be used. devm_counter_get() returns a reference to the counter_device structure. - counter_count_get() and counter_count_set() allow respectively to read and set a count value. - counter_function_get() and counter_function_set() allow to read and set the current count function. - counter_action_get() and counter_action_set allow to read and set the current count action/synapse. Signed-off-by: Kamel Bouhara --- drivers/counter/counter.c | 213 ++++++++++++++++++++++++++++++++++++++ include/linux/counter.h | 27 +++++ 2 files changed, 240 insertions(+) diff --git a/drivers/counter/counter.c b/drivers/counter/counter.c index 6a683d086008..f81d2d1dbca7 100644 --- a/drivers/counter/counter.c +++ b/drivers/counter/counter.c @@ -19,6 +19,7 @@ #include #include #include +#include const char *const counter_count_direction_str[2] = { [COUNTER_COUNT_DIRECTION_FORWARD] = "forward", @@ -1460,6 +1461,218 @@ static int devm_counter_match(struct device *dev, void *res, void *data) return *r == data; } +static int match(struct device *dev, const void *data) +{ + return (dev->of_node == data) && + (dev->type == &counter_device_type); +} + +/* Internal counter request function */ +static struct counter_device *counter_get(struct device *dev) +{ + struct device_node *np; + struct device *counter_dev; + struct counter_device_state *counter_ds; + struct counter_device *counter; + + /* Try DT lookup */ + np = of_parse_phandle(dev->of_node, "counter", 0); + if (!np) { + dev_dbg(dev, + "Looking up from device tree %pOF failed\n", np); + return ERR_PTR(-ENODEV); + } + + counter_dev = bus_find_device(&counter_bus_type, NULL, np, match); + of_node_put(np); + if (!counter_dev) + return ERR_PTR(-EPROBE_DEFER); + + counter_ds = to_counter_device_state(counter_dev); + + counter = dev_get_drvdata(&counter_ds->dev); + if (!counter) + return ERR_PTR(-ENODEV); + + /* Check if device is already owned otherwise set the busy bit */ + if (test_and_set_bit(COUNTER_BUSY_BIT_POS, &counter->flags)) { + pr_info("counter is busy\n"); + return ERR_PTR(-EBUSY); + } + + pr_info("counter acquired\n"); + get_device(&counter_ds->dev); + + return counter; +} + +static void devm_counter_release(struct device *dev, void *res) +{ + struct counter_device *counter = *(struct counter_device **)res; + + if (!counter) + return; + clear_bit(COUNTER_BUSY_BIT_POS, &counter->flags); + put_device(&counter->device_state->dev); +} + +/* + * devm_counter_get - Obtain an exclusive access to a counter. + * @dev: device for counter "consumer" + * + * Returns a struct counter_device matching the counter producer, or + * IS_ERR() condition containing errno. + * + */ +struct counter_device *devm_counter_get(struct device *dev) +{ + struct counter_device **ptr, *counter; + + ptr = devres_alloc(devm_counter_release, sizeof(*ptr), GFP_KERNEL); + if (!ptr) + return ERR_PTR(-ENOMEM); + + counter = counter_get(dev); + if (IS_ERR(counter)) { + devres_free(ptr); + return counter; + } + + *ptr = counter; + devres_add(dev, ptr); + + return counter; +} +EXPORT_SYMBOL_GPL(devm_counter_get); + +/* + * counter_action_get - get counter synapse mode + * @counter: counter device to operate with + * @action: pointer to store the current counter synapse mode + * returns: + * 0 on success, error code on failure. + */ +int counter_action_get(struct counter_device *counter, int *mode) +{ + struct counter_synapse *synapse = counter->counts->synapses; + size_t action_index; + int err; + + err = counter->ops->action_get(counter, counter->counts, synapse, + &action_index); + if (err) + return err; + + *mode = synapse->actions_list[action_index]; + + return 0; +} +EXPORT_SYMBOL_GPL(counter_action_get); + +/* + * counter_action_set - set counter device synapse + * @counter: counter device to operate with + * @action: enum of the synapse mode + * returns: + * 0 on success, error code on failure. + */ +int counter_action_set(struct counter_device *counter, + enum counter_synapse_action action) +{ + struct counter_synapse *synapse = counter->counts->synapses; + const size_t num_actions = synapse->num_actions; + size_t action_index; + + /* Find requested action mode */ + for (action_index = 0; action_index < num_actions; action_index++) { + if (action == synapse->actions_list[action_index]) + break; + } + + if (action_index >= num_actions) + return -EINVAL; + + return counter->ops->action_set(counter, counter->counts, synapse, + action_index); +} +EXPORT_SYMBOL_GPL(counter_action_set); + +/* + * counter_function_get - get the count function + * @counter: pointer to counter device to operate with + * @mode: pointer to store the current counter function mode + * returns: + * 0 on success, error code on failure. + */ +int counter_function_get(struct counter_device *counter, int *mode) +{ + size_t func_index; + int err; + + err = counter->ops->function_get(counter, counter->counts, + &func_index); + if (err) + return err; + + *mode = counter->counts->functions_list[func_index]; + + return 0; +} +EXPORT_SYMBOL_GPL(counter_function_get); + +/* + * counter_function_set - set a count function + * @counter: pointer to a counter device to operate with + * @function: enum of the function mode + * returns: + * 0 on success, error code on failure. + */ +int counter_function_set(struct counter_device *counter, + enum counter_count_function function) +{ + const size_t num_functions = counter->counts->num_functions; + size_t func_index; + + for (func_index = 0; func_index < num_functions; func_index++) { + if (function == counter->counts->functions_list[func_index]) + break; + } + + if (func_index >= num_functions) + return -EINVAL; + + return counter->ops->function_set(counter, counter->counts, func_index); +} +EXPORT_SYMBOL_GPL(counter_function_set); + +/* + * counter_count_set - set a count value + * @counter: pointer to the counter device to operate with + * @val: count value to write into the counter + * @len: length of the value written to the counter + * returns: + * bytes length of the value on success, error code on failure. + */ +size_t counter_count_set(struct counter_device *counter, + unsigned long val, size_t len) +{ + return counter->ops->count_write(counter, counter->counts, val); +} +EXPORT_SYMBOL_GPL(counter_count_set); + +/* + * counter_count_get - read the count value + * @counter: pointer to the counter device to operate with + * @val: pointer to store the count value + * returns: + * 0 on success, error code on failure. + */ +int counter_count_get(struct counter_device *counter, unsigned long *val) +{ + return counter->ops->count_read(counter, counter->counts, val); +} +EXPORT_SYMBOL_GPL(counter_count_get); + /** * devm_counter_unregister - Resource-managed counter_unregister * @dev: device this counter_device belongs to diff --git a/include/linux/counter.h b/include/linux/counter.h index 9dbd5df4cd34..81f63479be55 100644 --- a/include/linux/counter.h +++ b/include/linux/counter.h @@ -10,6 +10,8 @@ #include #include +#define COUNTER_BUSY_BIT_POS 1 + enum counter_count_direction { COUNTER_COUNT_DIRECTION_FORWARD = 0, COUNTER_COUNT_DIRECTION_BACKWARD @@ -290,6 +292,15 @@ struct counter_device_state { const struct attribute_group **groups; }; +/** + * to_counter_device_state - Returns a &struct counter_device_state + * from the &struct device embedded in it. + * + * @d:pointer to &struct device + */ +#define to_counter_device_state(d) \ + container_of(d, struct counter_device_state, dev) + enum counter_signal_value { COUNTER_SIGNAL_LOW = 0, COUNTER_SIGNAL_HIGH @@ -424,6 +435,7 @@ struct counter_device_enum_ext { * @num_counts: number of Counts specified in @counts * @ext: optional array of Counter device extensions * @num_ext: number of Counter device extensions specified in @ext + * @flags: internal device flags including a busy flag. * @priv: optional private data supplied by driver */ struct counter_device { @@ -440,6 +452,7 @@ struct counter_device { const struct counter_device_ext *ext; size_t num_ext; + unsigned long flags; void *priv; }; @@ -450,5 +463,19 @@ int devm_counter_register(struct device *dev, struct counter_device *const counter); void devm_counter_unregister(struct device *dev, struct counter_device *const counter); +/* inkernel interface */ +int __must_check counter_count_get(struct counter_device *counter, + unsigned long *val); +size_t __must_check counter_count_set(struct counter_device *counter, + unsigned long val, size_t len); +int __must_check counter_function_get(struct counter_device *counter, + int *mode); +int __must_check counter_function_set(struct counter_device *counter, + enum counter_count_function function); +int __must_check counter_action_get(struct counter_device *counter, + int *mode); +int __must_check counter_action_set(struct counter_device *counter, + enum counter_synapse_action action); +struct counter_device *__must_check devm_counter_get(struct device *dev); #endif /* _COUNTER_H_ */ From patchwork Mon Apr 6 15:58:05 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Kamel BOUHARA X-Patchwork-Id: 207968 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-9.8 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH, MAILING_LIST_MULTI, SIGNED_OFF_BY, SPF_HELO_NONE, SPF_PASS, URIBL_BLOCKED, USER_AGENT_GIT autolearn=unavailable autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id E6870C2BABC for ; Mon, 6 Apr 2020 15:58:36 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id C4BB2248EA for ; Mon, 6 Apr 2020 15:58:36 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1729211AbgDFP6a (ORCPT ); Mon, 6 Apr 2020 11:58:30 -0400 Received: from relay12.mail.gandi.net ([217.70.178.232]:36043 "EHLO relay12.mail.gandi.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1729174AbgDFP63 (ORCPT ); Mon, 6 Apr 2020 11:58:29 -0400 Received: from localhost (unknown [78.193.40.249]) (Authenticated sender: kamel.bouhara@bootlin.com) by relay12.mail.gandi.net (Postfix) with ESMTPSA id D216B20000E; Mon, 6 Apr 2020 15:58:26 +0000 (UTC) From: Kamel Bouhara To: Dmitry Torokhov , William Breathitt Gray , Rob Herring , Mark Rutland Cc: Nicolas Ferre , Alexandre Belloni , Ludovic Desroches , linux-arm-kernel@lists.infradead.org, Thomas Petazzoni , linux-input@vger.kernel.org, devicetree@vger.kernel.org, linux-kernel@vger.kernel.org, linux-iio@vger.kernel.org, Kamel Bouhara Subject: [PATCH 2/3] Input: rotary-encoder-counter: add DT bindings Date: Mon, 6 Apr 2020 17:58:05 +0200 Message-Id: <20200406155806.1295169-3-kamel.bouhara@bootlin.com> X-Mailer: git-send-email 2.25.0 In-Reply-To: <20200406155806.1295169-1-kamel.bouhara@bootlin.com> References: <20200406155806.1295169-1-kamel.bouhara@bootlin.com> MIME-Version: 1.0 Sender: linux-input-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-input@vger.kernel.org Add dt binding for the counter variant of the rotary encoder driver. Signed-off-by: Kamel Bouhara --- .../input/rotary-encoder-counter.yaml | 67 +++++++++++++++++++ 1 file changed, 67 insertions(+) create mode 100644 Documentation/devicetree/bindings/input/rotary-encoder-counter.yaml diff --git a/Documentation/devicetree/bindings/input/rotary-encoder-counter.yaml b/Documentation/devicetree/bindings/input/rotary-encoder-counter.yaml new file mode 100644 index 000000000000..a59f7c1faf0c --- /dev/null +++ b/Documentation/devicetree/bindings/input/rotary-encoder-counter.yaml @@ -0,0 +1,67 @@ +# SPDX-License-Identifier: GPL-2.0 +%YAML 1.2 +--- +$id: http://devicetree.org/schemas/input/rotary-encoder-counter.yaml# +$schema: http://devicetree.org/meta-schemas/core.yaml# + +title: Rotary Encoder Counter + +maintainers: + - Kamel Bouhara + +description: + Registers a Rotary encoder connected through a counter device. + +properties: + compatible: + const: rotary-encoder-counter + + counter: + description: Phandle for the counter device providing rotary position. + + linux-axis: + description: The input subsystem axis to map to this rotary encoder. + type: boolean + + qdec-mode: + description: | + Quadrature decoder function to set in the counter device. + 3: x1-PHA + 4: x1-PHB + 5: x2-PHA + 6: x2-PHB + 7: x4-PHA and PHB + + steps: + description: Number of steps in a full turnaround of the encoder. + Only relevant for absolute axis. Defaults to 24 which is a typical + value for such devices. + + relative-axis: + description: Register a relative axis rather than an absolute one. + type: boolean + + rollover: + description: Automatic rollover when the rotary value becomes greater + than the specified steps or smaller than 0. For absolute axis only. + type: boolean + + poll-interval: + description: Poll interval at which the position is read from the counter + device (default 500ms). + +required: + - compatible + - counter + - qdec-mode + +examples: + - | + rotary@0 { + compatible = "rotary-encoder-counter"; + + counter =<&qdec>; + qdec-mode = <7>; + relative-axis; + }; +... From patchwork Mon Apr 6 15:53:20 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Kamel BOUHARA X-Patchwork-Id: 207970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-9.8 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH, MAILING_LIST_MULTI, SIGNED_OFF_BY, SPF_HELO_NONE, SPF_PASS, URIBL_BLOCKED, USER_AGENT_GIT autolearn=unavailable autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 04B61C2BB1D for ; Mon, 6 Apr 2020 15:54:19 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id D1A3C21D94 for ; Mon, 6 Apr 2020 15:54:18 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1729208AbgDFPyS (ORCPT ); Mon, 6 Apr 2020 11:54:18 -0400 Received: from relay9-d.mail.gandi.net ([217.70.183.199]:39607 "EHLO relay9-d.mail.gandi.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1729195AbgDFPyR (ORCPT ); Mon, 6 Apr 2020 11:54:17 -0400 X-Originating-IP: 78.193.40.249 Received: from localhost (unknown [78.193.40.249]) (Authenticated sender: kamel.bouhara@bootlin.com) by relay9-d.mail.gandi.net (Postfix) with ESMTPSA id A6C5DFF809; Mon, 6 Apr 2020 15:54:14 +0000 (UTC) From: Kamel Bouhara To: William Breathitt Gray , Rob Herring , Mark Rutland , Nicolas Ferre , Alexandre Belloni , Ludovic Desroches , linux-arm-kernel@lists.infradead.org Cc: Thomas Petazzoni , linux-input@vger.kernel.org, devicetree@vger.kernel.org, linux-iio@vger.kernel.org, Kamel Bouhara Subject: [PATCH 3/3] counter: Add atmel TCB capture counter Date: Mon, 6 Apr 2020 17:53:20 +0200 Message-Id: <20200406155320.1291701-4-kamel.bouhara@bootlin.com> X-Mailer: git-send-email 2.25.0 In-Reply-To: <20200406155320.1291701-1-kamel.bouhara@bootlin.com> References: <20200406155320.1291701-1-kamel.bouhara@bootlin.com> MIME-Version: 1.0 Sender: linux-input-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-input@vger.kernel.org This drivers allows to use the capture mode of the Timer Counter Block hardware block available in Atmel SoCs through the counter subsystem. Two functions of the counter are supported for the moment: period capture and quadrature decoder. The latter is only supported by the SAMA5 series of SoCs. For the period capture mode a basic setup has been chosen that will reset the counter each time the period is actually reached. Of course the device offers much more possibilities. For quadrature mode, both channel 0 and 1 must be configured even if we only capture the position (no revolution/rotation). Signed-off-by: Kamel Bouhara --- drivers/counter/Kconfig | 11 + drivers/counter/Makefile | 1 + drivers/counter/atmel-tcb-capture.c | 388 ++++++++++++++++++++++++++++ 3 files changed, 400 insertions(+) create mode 100644 drivers/counter/atmel-tcb-capture.c diff --git a/drivers/counter/Kconfig b/drivers/counter/Kconfig index c80fa76bb531..c50d7453ec33 100644 --- a/drivers/counter/Kconfig +++ b/drivers/counter/Kconfig @@ -70,4 +70,15 @@ config FTM_QUADDEC To compile this driver as a module, choose M here: the module will be called ftm-quaddec. +config ATMEL_TCB_CAPTURE + tristate "Atmel Timer Counter Capture driver" + depends on HAS_IOMEM && OF + select REGMAP_MMIO + help + Select this option to enable the Atmel Timer Counter Block + capture driver. + + To compile this driver as a module, choose M here: the + module will be called atmel-tcb-capture. + endif # COUNTER diff --git a/drivers/counter/Makefile b/drivers/counter/Makefile index 55142d1f4c43..70c5b8924588 100644 --- a/drivers/counter/Makefile +++ b/drivers/counter/Makefile @@ -10,3 +10,4 @@ obj-$(CONFIG_STM32_TIMER_CNT) += stm32-timer-cnt.o obj-$(CONFIG_STM32_LPTIMER_CNT) += stm32-lptimer-cnt.o obj-$(CONFIG_TI_EQEP) += ti-eqep.o obj-$(CONFIG_FTM_QUADDEC) += ftm-quaddec.o +obj-$(CONFIG_ATMEL_TCB_CAPTURE) += atmel-tcb-capture.o diff --git a/drivers/counter/atmel-tcb-capture.c b/drivers/counter/atmel-tcb-capture.c new file mode 100644 index 000000000000..6ac809503f90 --- /dev/null +++ b/drivers/counter/atmel-tcb-capture.c @@ -0,0 +1,388 @@ +// SPDX-License-Identifier: GPL-2.0-only +/** + * Copyright (C) 2020 Atmel + * + * Author: Kamel Bouhara + * + */ +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include + +#define ATMEL_TC_CMR_MASK (ATMEL_TC_LDRA_RISING | ATMEL_TC_LDRB_FALLING | \ + ATMEL_TC_ETRGEDG_RISING | ATMEL_TC_LDBDIS | \ + ATMEL_TC_LDBSTOP) + +#define ATMEL_TC_QDEN BIT(8) +#define ATMEL_TC_POSEN BIT(9) + +struct atmel_tc_data { + const struct atmel_tcb_config *tc_cfg; + struct counter_device counter; + struct regmap *regmap; + int qdec_mode; + int num_channels; + int channel[2]; + bool trig_inverted; +}; + +enum atmel_tc_count_function { + ATMEL_TC_FUNCTION_INCREASE, + ATMEL_TC_FUNCTION_QUADRATURE, +}; + +static enum counter_count_function atmel_tc_count_functions[] = { + [ATMEL_TC_FUNCTION_INCREASE] = COUNTER_COUNT_FUNCTION_INCREASE, + [ATMEL_TC_FUNCTION_QUADRATURE] = COUNTER_COUNT_FUNCTION_QUADRATURE_X4, +}; + +enum atmel_tc_synapse_action { + ATMEL_TC_SYNAPSE_ACTION_NONE = 0, + ATMEL_TC_SYNAPSE_ACTION_RISING_EDGE, + ATMEL_TC_SYNAPSE_ACTION_FALLING_EDGE, + ATMEL_TC_SYNAPSE_ACTION_BOTH_EDGE +}; + +static enum counter_synapse_action atmel_tc_synapse_actions[] = { + [ATMEL_TC_SYNAPSE_ACTION_NONE] = COUNTER_SYNAPSE_ACTION_NONE, + [ATMEL_TC_SYNAPSE_ACTION_RISING_EDGE] = COUNTER_SYNAPSE_ACTION_RISING_EDGE, + [ATMEL_TC_SYNAPSE_ACTION_FALLING_EDGE] = COUNTER_SYNAPSE_ACTION_FALLING_EDGE, + [ATMEL_TC_SYNAPSE_ACTION_BOTH_EDGE] = COUNTER_SYNAPSE_ACTION_BOTH_EDGES, +}; + +static struct counter_signal atmel_tc_count_signals[] = { + { + .id = 0, + .name = "Channel A", + }, + { + .id = 1, + .name = "Channel B", + } +}; + +static struct counter_synapse atmel_tc_count_synapses[] = { + { + .actions_list = atmel_tc_synapse_actions, + .num_actions = ARRAY_SIZE(atmel_tc_synapse_actions), + .signal = &atmel_tc_count_signals[0] + }, + { + .actions_list = atmel_tc_synapse_actions, + .num_actions = ARRAY_SIZE(atmel_tc_synapse_actions), + .signal = &atmel_tc_count_signals[1] + } +}; + +static int atmel_tc_count_function_get(struct counter_device *counter, + struct counter_count *count, + size_t *function) +{ + struct atmel_tc_data *const priv = counter->priv; + + if (priv->qdec_mode) + *function = ATMEL_TC_FUNCTION_QUADRATURE; + else + *function = ATMEL_TC_FUNCTION_INCREASE; + + return 0; +} + +static int atmel_tc_count_function_set(struct counter_device *counter, + struct counter_count *count, + size_t function) +{ + struct atmel_tc_data *const priv = counter->priv; + u32 bmr, cmr; + + regmap_read(priv->regmap, ATMEL_TC_BMR, &bmr); + regmap_read(priv->regmap, ATMEL_TC_REG(priv->channel[0], CMR), &cmr); + + /* Set capture mode */ + cmr &= ~ATMEL_TC_WAVE; + + switch (function) { + case ATMEL_TC_FUNCTION_INCREASE: + priv->qdec_mode = 0; + /* Set highest rate based on whether soc has gclk or not */ + bmr &= ~(ATMEL_TC_QDEN | ATMEL_TC_POSEN); + if (priv->tc_cfg->has_gclk) + cmr |= ATMEL_TC_TIMER_CLOCK2; + else + cmr |= ATMEL_TC_TIMER_CLOCK1; + /* Setup the period capture mode */ + cmr |= ATMEL_TC_CMR_MASK; + cmr &= ~(ATMEL_TC_ABETRG | ATMEL_TC_XC0); + break; + case ATMEL_TC_FUNCTION_QUADRATURE: + if (!priv->tc_cfg->has_qdec) + return -ENODEV; + /* In QDEC mode settings both channels 0 and 1 are required */ + if (priv->num_channels < 2 || priv->channel[0] != 0 || + priv->channel[1] != 1) { + pr_err("Invalid channels number or id for quadrature mode\n"); + return -EINVAL; + } + priv->qdec_mode = 1; + bmr |= ATMEL_TC_QDEN | ATMEL_TC_POSEN; + cmr |= ATMEL_TC_ETRGEDG_RISING | ATMEL_TC_ABETRG | ATMEL_TC_XC0; + break; + } + + regmap_write(priv->regmap, ATMEL_TC_BMR, bmr); + regmap_write(priv->regmap, ATMEL_TC_REG(priv->channel[0], CMR), cmr); + + /* Enable clock and trigger counter */ + regmap_write(priv->regmap, ATMEL_TC_REG(priv->channel[0], CCR), + ATMEL_TC_CLKEN | ATMEL_TC_SWTRG); + + if (priv->qdec_mode) { + regmap_write(priv->regmap, + ATMEL_TC_REG(priv->channel[1], CMR), cmr); + regmap_write(priv->regmap, + ATMEL_TC_REG(priv->channel[1], CCR), + ATMEL_TC_CLKEN | ATMEL_TC_SWTRG); + } + + return 0; +} + +static int atmel_tc_count_signal_read(struct counter_device *counter, + struct counter_signal *signal, + enum counter_signal_value *val) +{ + struct atmel_tc_data *const priv = counter->priv; + bool sigstatus; + u32 sr; + + regmap_read(priv->regmap, ATMEL_TC_REG(priv->channel[0], SR), &sr); + + if (priv->trig_inverted) + sigstatus = (sr & ATMEL_TC_MTIOB); + else + sigstatus = (sr & ATMEL_TC_MTIOA); + + *val = sigstatus ? COUNTER_SIGNAL_HIGH : COUNTER_SIGNAL_LOW; + + return 0; +} + +static int atmel_tc_count_action_get(struct counter_device *counter, + struct counter_count *count, + struct counter_synapse *synapse, + size_t *action) +{ + struct atmel_tc_data *const priv = counter->priv; + u32 cmr; + + regmap_read(priv->regmap, ATMEL_TC_REG(priv->channel[0], CMR), &cmr); + + *action = ATMEL_TC_SYNAPSE_ACTION_NONE; + + if (cmr & ATMEL_TC_ETRGEDG_NONE) + *action = ATMEL_TC_SYNAPSE_ACTION_NONE; + else if (cmr & ATMEL_TC_ETRGEDG_RISING) + *action = ATMEL_TC_SYNAPSE_ACTION_RISING_EDGE; + else if (cmr & ATMEL_TC_ETRGEDG_FALLING) + *action = ATMEL_TC_SYNAPSE_ACTION_FALLING_EDGE; + else if (cmr & ATMEL_TC_ETRGEDG_BOTH) + *action = ATMEL_TC_SYNAPSE_ACTION_BOTH_EDGE; + + return 0; +} + +static int atmel_tc_count_action_set(struct counter_device *counter, + struct counter_count *count, + struct counter_synapse *synapse, + size_t action) +{ + struct atmel_tc_data *const priv = counter->priv; + u32 edge = ATMEL_TC_ETRGEDG_NONE; + + switch (action) { + case ATMEL_TC_SYNAPSE_ACTION_NONE: + edge = ATMEL_TC_ETRGEDG_NONE; + break; + case ATMEL_TC_SYNAPSE_ACTION_RISING_EDGE: + edge = ATMEL_TC_ETRGEDG_RISING; + break; + case ATMEL_TC_SYNAPSE_ACTION_FALLING_EDGE: + edge = ATMEL_TC_ETRGEDG_FALLING; + break; + case ATMEL_TC_SYNAPSE_ACTION_BOTH_EDGE: + edge = ATMEL_TC_ETRGEDG_BOTH; + break; + } + + return regmap_write_bits(priv->regmap, + ATMEL_TC_REG(priv->channel[0], CMR), + ATMEL_TC_ETRGEDG, edge); +} + +static int atmel_tc_count_read(struct counter_device *counter, + struct counter_count *count, + unsigned long *val) +{ + struct atmel_tc_data *const priv = counter->priv; + u32 cnt; + + regmap_read(priv->regmap, ATMEL_TC_REG(priv->channel[0], CV), &cnt); + *val = cnt; + + return 0; +} + +static struct counter_count atmel_tc_count = { + .id = 0, + .name = "Timer Counter", + .functions_list = atmel_tc_count_functions, + .num_functions = ARRAY_SIZE(atmel_tc_count_functions), + .synapses = atmel_tc_count_synapses, + .num_synapses = ARRAY_SIZE(atmel_tc_count_synapses), +}; + +static struct counter_ops atmel_tc_ops = { + .signal_read = atmel_tc_count_signal_read, + .count_read = atmel_tc_count_read, + .count_write = NULL, + .function_get = atmel_tc_count_function_get, + .function_set = atmel_tc_count_function_set, + .action_get = atmel_tc_count_action_get, + .action_set = atmel_tc_count_action_set +}; + +static const struct atmel_tcb_config tcb_rm9200_config = { + .counter_width = 16, +}; + +static const struct atmel_tcb_config tcb_sam9x5_config = { + .counter_width = 32, +}; + +static const struct atmel_tcb_config tcb_sama5d2_config = { + .counter_width = 32, + .has_gclk = true, + .has_qdec = true, +}; + +static const struct atmel_tcb_config tcb_sama5d3_config = { + .counter_width = 32, + .has_qdec = true, +}; + +static const struct of_device_id atmel_tc_of_match[] = { + { .compatible = "atmel,at91rm9200-tcb", .data = &tcb_rm9200_config, }, + { .compatible = "atmel,at91sam9x5-tcb", .data = &tcb_sam9x5_config, }, + { .compatible = "atmel,sama5d2-tcb", .data = &tcb_sama5d2_config, }, + { .compatible = "atmel,sama5d3-tcb", .data = &tcb_sama5d3_config, }, + { /* sentinel */ } +}; + +static int atmel_tc_probe(struct platform_device *pdev) +{ + struct device_node *np = pdev->dev.of_node; + const struct atmel_tcb_config *tcb_config; + const struct of_device_id *match; + struct atmel_tc_data *priv; + char clk_name[] = "t0_clk"; + struct regmap *regmap; + struct clk *clk[3]; + int channel; + int ret, i; + + priv = devm_kzalloc(&pdev->dev, sizeof(*priv), GFP_KERNEL); + if (!priv) + return -ENOMEM; + + platform_set_drvdata(pdev, priv); + + match = of_match_node(atmel_tc_of_match, np->parent); + tcb_config = match->data; + if (!tcb_config) { + dev_err(&pdev->dev, "No matching parent node found\n"); + return -ENODEV; + } + + regmap = syscon_node_to_regmap(np->parent); + if (IS_ERR(priv->regmap)) + return PTR_ERR(priv->regmap); + + /* max. channels number is 2 when in QDEC mode */ + priv->num_channels = of_property_count_u32_elems(np, "reg"); + if (priv->num_channels < 0) { + dev_err(&pdev->dev, "Invalid or missing channel\n"); + return -EINVAL; + } + + /* Register channels and initialize clocks */ + for (i = 0; i < priv->num_channels; i++) { + ret = of_property_read_u32_index(np, "reg", i, &channel); + if (ret < 0 || channel > 2) + return -ENODEV; + + priv->channel[i] = channel; + + clk_name[1] += channel; + clk[i] = of_clk_get_by_name(np->parent, clk_name); + if (IS_ERR(clk[i])) { + /* Fallback to t0_clk */ + clk[i] = of_clk_get_by_name(np->parent, "t0_clk"); + if (IS_ERR(clk[i])) + return PTR_ERR(clk[i]); + } + + ret = clk_prepare_enable(clk[i]); + if (ret) + return ret; + + dev_info(&pdev->dev, + "Initialized capture mode on channel %d\n", + channel); + } + + priv->tc_cfg = tcb_config; + priv->regmap = regmap; + priv->counter.name = dev_name(&pdev->dev); + priv->counter.parent = &pdev->dev; + priv->counter.ops = &atmel_tc_ops; + priv->counter.num_counts = 1; + priv->counter.counts = &atmel_tc_count; + priv->counter.num_signals = ARRAY_SIZE(atmel_tc_count_signals); + priv->counter.signals = atmel_tc_count_signals; + priv->counter.priv = priv; + + ret = devm_counter_register(&pdev->dev, &priv->counter); + if (ret < 0) { + for (i = 0; i < priv->num_channels; i++) + clk_disable_unprepare(clk[i]); + return ret; + } + + return 0; +} + +static const struct of_device_id atmel_tc_dt_ids[] = { + { .compatible = "atmel,tcb-capture", }, + { /* sentinel */ }, +}; +MODULE_DEVICE_TABLE(of, atmel_tc_dt_ids); + +static struct platform_driver atmel_tc_driver = { + .probe = atmel_tc_probe, + .driver = { + .name = "atmel-tcb-capture", + .of_match_table = atmel_tc_dt_ids, + }, +}; +module_platform_driver(atmel_tc_driver); + +MODULE_AUTHOR("Kamel Bouhara "); +MODULE_DESCRIPTION("Atmel TCB Capture driver"); +MODULE_LICENSE("GPL v2");