From patchwork Thu Feb 16 20:38:28 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Biju Das X-Patchwork-Id: 13143786 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 DCB0BC6379F for ; Thu, 16 Feb 2023 20:39:03 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S229834AbjBPUjC (ORCPT ); Thu, 16 Feb 2023 15:39:02 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:53046 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229556AbjBPUjB (ORCPT ); Thu, 16 Feb 2023 15:39:01 -0500 Received: from relmlie6.idc.renesas.com (relmlor2.renesas.com [210.160.252.172]) by lindbergh.monkeyblade.net (Postfix) with ESMTP id 46C111ADE6; Thu, 16 Feb 2023 12:38:57 -0800 (PST) X-IronPort-AV: E=Sophos;i="5.97,302,1669042800"; d="scan'208";a="153127622" Received: from unknown (HELO relmlir5.idc.renesas.com) ([10.200.68.151]) by relmlie6.idc.renesas.com with ESMTP; 17 Feb 2023 05:38:56 +0900 Received: from localhost.localdomain (unknown [10.226.93.2]) by relmlir5.idc.renesas.com (Postfix) with ESMTP id 159DE40121D0; Fri, 17 Feb 2023 05:38:52 +0900 (JST) From: Biju Das To: William Breathitt Gray Cc: Biju Das , linux-iio@vger.kernel.org, Lee Jones , "Daniel Lezcano" , "Thierry Reding" , =?utf-8?q?Uwe_Kleine-K=C3=B6ni?= =?utf-8?q?g?= , Geert Uytterhoeven , Chris Paterson , Prabhakar Mahadev Lad , linux-renesas-soc@vger.kernel.org Subject: [PATCH v13 4/6] counter: Add Renesas RZ/G2L MTU3a counter driver Date: Thu, 16 Feb 2023 20:38:28 +0000 Message-Id: <20230216203830.196632-5-biju.das.jz@bp.renesas.com> X-Mailer: git-send-email 2.25.1 In-Reply-To: <20230216203830.196632-1-biju.das.jz@bp.renesas.com> References: <20230216203830.196632-1-biju.das.jz@bp.renesas.com> MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: linux-iio@vger.kernel.org Add RZ/G2L MTU3a counter driver. This IP supports the following phase counting modes on MTU1 and MTU2 channels 1) 16-bit phase counting modes on MTU1 and MTU2 channels. 2) 32-bit phase counting mode by cascading MTU1 and MTU2 channels. This patch adds 3 counter value channels. count0: 16-bit phase counter value channel on MTU1 count1: 16-bit phase counter value channel on MTU2 count2: 32-bit phase counter value channel by cascading MTU1 and MTU2 channels. The external input phase clock pin for the counter value channels are as follows: count0: "MTCLKA-MTCLKB" count1: "MTCLKA-MTCLKB" or "MTCLKC-MTCLKD" count2: "MTCLKA-MTCLKB" or "MTCLKC-MTCLKD" Use the sysfs variable "external_input_phase_clock_select" to select the external input phase clock pin and "cascade_counts_enable" to enable/ disable cascading of channels. Signed-off-by: Biju Das Reviewed-by: William Breathitt Gray Acked-by: William Breathitt Gray --- v12->v13: * No change. v11->v12: * Updated header file to as core driver is moved to MFD. v10->v11: * Added Rb tag from William Breathitt Gray * Replaced count2 channel name from "combined"->"cascaded", as channels are cascaded * Simplified the locking by adding the helper functions rz_mtu3_lock_if_counter_is_valid, rz_mtu3_lock_if_count_is_enabled, and rz_mtu3_lock_if_ch0_is_enabled. v9->v10: * Added helper function for rz_mtu3_count_{action,function}_read * Added priv->lock in rz_mtu3_count_function_read and rz_mtu3_count_ direction_read. * Added ch->is_busy check for rz_mtu3_action_read() * Added rz_mtu3_is_ch0_enabled() for device specific sysfs variables. * Added ch->is_busy check for device specific sysfs variables. v8->v9: * Added count_is_enabled variable to struct rz_mtu3_cnt * Added check for ch->is_busy and count_is_enabled before every Counter callback to ensure we do not try to access a busy channel used by other subsystem(eg: pwm). * Removed id parameter from rz_mtu3_32bit_cnt_setting() * Made definition of rz_mtu3_get_ch() in single line. * Replaced break->return in rz_mtu3_32bit_cnt_setting(), rz_mtu3_count_function_read() and rz_mtu3_initialize_counter() and removed redundant return 0. * Simplified synapse signal check for rz_mtu3_action_read(). v7->v8: * Simplified rz_mtu3_initialize_counter by calling rz_mtu3_request_ channel() and release the acquired sibling channel in case of error. * Simplified rz_mtu3_terminate_counter by calling rz_mtu3_release_ channel(). * Removed unused ceiling and ch_id from rz_mtu3_count_write() * Replaced the error -EINVAL->-EBUSY for rz_mtu3_is_counter_invalid() * Avoided race between rz_mtu3_count_{read, write} with rz_mtu3_ cascade_counts_enable_set() by adding locks and moved the lock before rz_mtu3_is_counter_invalid() * Protected the rz_mtu3_count_ceiling_read() function with a lock to make sure the cascade operation mode doesn't not change and that the priv data structure accesses don't race when they are changed in the ceiling_write() callback. * Added lock in rz_mtu3_cascade_enable_set() to make sure the other callbacks don't try to read the LWA state while updating LWA. * Added lock in rz_mtu3_ext_input_phase_clock_select_set() to ensure the other callbacks don't try to read the PHCKSEL state while updating PHCKSEL. * Added lock to avoid race between rz_mtu3_count_function_write() and rz_mtu3_action_read() * Updated rz_mtu3_action_read to return 0, if Synapse is in COUNTER_SYNAPSE _ACTION_NONE state. * Replaced sysfs variable cascade_enable->cascade_counts_enable * Renamed rz_mtu3_cascade_enable_get->rz_mtu3_cascade_counts_enable_get * Renamed rz_mtu3_cascade_enable_set->rz_mtu3_cascade_counts_enable_set * Removed redundent ceiling assignment from rz_mtu3_count_ceiling_read() * Removed unused ceiling and ch_id from rz_mtu3_count_write(). v6->v7: * Updated commit description * Added Register descriptions * Opimized size of cache variable by using union * Used test_bit() in rz_mtu3_is_counter_invalid() * Replaced val->timer_mode in rz_mtu3_count_function_{read,write} * Added TODO comment phase3 and phase5 modes. * replaced if-else with ternary expression in rz_mtu3_count_direction_read() * Used switch statement in rz_mtu3_count_ceiling_read to consistent with write * Provided default case for all switch statement. * Add mutex lock for avoiding races with other devices * Updated comments in rz_mtu3_action_read * Replaced COUNTER_COMP_DEVICE_BOOL->COUNTER_COMP_DEVICE_BOOL for cascade_enable * Replaced RZ_MTU3_GET_HW_CH->rz_mtu3_get_hw_ch * Added rz_mtu3_get_ch() to get channels * used rz_mtu3_shared_reg_update_bit for cascade_enable and selecting phase input clock. * Added rz_mtu3_is_counter_invalid() check in rz_mtu3_count_ceiling_read() v5->v6: * Updated KConfig and commit description * Sorted header * Fixed RZ_MTU3_GET_HW_CH Macro for argument reuse 'id' - possible side-effects? * Replaced SET_RUNTIME_PM_OPS->DEFINE_RUNTIME_DEV_PM_OPS and removed __maybe_unused from suspend/resume() v4->v5: * Updated the Kconfig with SoC vendor name * Introduced rz_mtu3_is_counter_invalid() * replaced pointer to an array of struct rz_mtu3_channel with a simple pointer to struct rz_mtu3_channel. * Added long_word_access_ctrl_mode sysfs entry for 16-bit and 32-bit access * Added external_input_phase_clock_select sysfs entry for selecting input clocks. * used preprocessor defines represent SIGNAL_{A,B,C,D}_ID instead of signal ids. v3->v4: * There is no resource associated with "rz-mtu3-counter" compatible and moved the code to mfd subsystem as it binds against "rz-mtu". * Removed struct platform_driver rz_mtu3_cnt_driver. * Updated commit description * Updated Kconfig description * Added macros RZ_MTU3_16_BIT_MTU{1,2}_CH for MTU1 and MTU2 channels * Added RZ_MTU3_GET_HW_CH macro for getting channel ID. * replaced priv->ch[id]->priv->ch[0] in rz_mtu3_count_read() * Cached counter max values * replaced cnt->tsr in rz_mtu3_count_direction_read() * Added comments for RZ_MTU3_TCR_CCLR_NONE * Replaced if with switch in rz_mtu3_initialize_counter() and rz_mtu3_count_ceiling_write() * Added locks in initialize, terminate and enable_read to prevent races. * Updated rz_mtu3_action_read to take care of MTU2 signals. * Added separate distinct array for each group of Synapse. * Moved pm handling to parent. v1->v3: * Modelled as a counter device supporting 3 counters(2 16-bit and 32-bit) * Add kernel-doc comments to document struct rz_mtu3_cnt * Removed mmio variable from struct rz_mtu3_cnt * Removed cnt local variable from rz_mtu3_count_read() * Replaced -EINVAL->-ERANGE for out of range error conditions. * Removed explicit cast from write functions. * Removed local variable val from rz_mtu3_count_ceiling_read() * Added lock for RMW for counter/ceiling updates. * Added different synapses for counter0 and counter{1,2} * Used ARRAY for assigning num_counts. * Added PM runtime for managing clocks. * Add MODULE_IMPORT_NS(COUNTER) to import the COUNTER namespace. --- drivers/counter/Kconfig | 11 + drivers/counter/Makefile | 1 + drivers/counter/rz-mtu3-cnt.c | 902 ++++++++++++++++++++++++++++++++++ 3 files changed, 914 insertions(+) create mode 100644 drivers/counter/rz-mtu3-cnt.c diff --git a/drivers/counter/Kconfig b/drivers/counter/Kconfig index b5ba8fb02cf7..4228be917038 100644 --- a/drivers/counter/Kconfig +++ b/drivers/counter/Kconfig @@ -73,6 +73,17 @@ config MICROCHIP_TCB_CAPTURE To compile this driver as a module, choose M here: the module will be called microchip-tcb-capture. +config RZ_MTU3_CNT + tristate "Renesas RZ/G2L MTU3a counter driver" + depends on RZ_MTU3 || COMPILE_TEST + help + Enable support for MTU3a counter driver found on Renesas RZ/G2L alike + SoCs. This IP supports both 16-bit and 32-bit phase counting mode + support. + + To compile this driver as a module, choose M here: the + module will be called rz-mtu3-cnt. + config STM32_LPTIMER_CNT tristate "STM32 LP Timer encoder counter driver" depends on MFD_STM32_LPTIMER || COMPILE_TEST diff --git a/drivers/counter/Makefile b/drivers/counter/Makefile index b9a369e0d4fc..933fdd50b3e4 100644 --- a/drivers/counter/Makefile +++ b/drivers/counter/Makefile @@ -8,6 +8,7 @@ counter-y := counter-core.o counter-sysfs.o counter-chrdev.o obj-$(CONFIG_104_QUAD_8) += 104-quad-8.o obj-$(CONFIG_INTERRUPT_CNT) += interrupt-cnt.o +obj-$(CONFIG_RZ_MTU3_CNT) += rz-mtu3-cnt.o obj-$(CONFIG_STM32_TIMER_CNT) += stm32-timer-cnt.o obj-$(CONFIG_STM32_LPTIMER_CNT) += stm32-lptimer-cnt.o obj-$(CONFIG_TI_EQEP) += ti-eqep.o diff --git a/drivers/counter/rz-mtu3-cnt.c b/drivers/counter/rz-mtu3-cnt.c new file mode 100644 index 000000000000..c4b5440da878 --- /dev/null +++ b/drivers/counter/rz-mtu3-cnt.c @@ -0,0 +1,902 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * Renesas RZ/G2L MTU3a Counter driver + * + * Copyright (C) 2022 Renesas Electronics Corporation + */ + +#include +#include +#include +#include +#include +#include +#include + +/* + * Register descriptions + * TSR: Timer Status Register + * TMDR1: Timer Mode Register 1 + * TMDR3: Timer Mode Register 3 + * TIOR: Timer I/O Control Register + * TCR: Timer Control Register + * TCNT: Timer Counter + * TGRA: Timer general register A + * TCNTLW: Timer Longword Counter + * TGRALW: Timer longword general register A + */ + +#define RZ_MTU3_TSR_TCFD BIT(7) /* Count Direction Flag */ + +#define RZ_MTU3_TMDR1_PH_CNT_MODE_1 (4) /* Phase counting mode 1 */ +#define RZ_MTU3_TMDR1_PH_CNT_MODE_2 (5) /* Phase counting mode 2 */ +#define RZ_MTU3_TMDR1_PH_CNT_MODE_3 (6) /* Phase counting mode 3 */ +#define RZ_MTU3_TMDR1_PH_CNT_MODE_4 (7) /* Phase counting mode 4 */ +#define RZ_MTU3_TMDR1_PH_CNT_MODE_5 (9) /* Phase counting mode 5 */ +#define RZ_MTU3_TMDR1_PH_CNT_MODE_MASK (0xf) + +/* + * LWA: MTU1/MTU2 Combination Longword Access Control + * 0: 16-bit, 1: 32-bit + */ +#define RZ_MTU3_TMDR3_LWA (0) + +/* + * PHCKSEL: External Input Phase Clock Select + * 0: MTCLKA and MTCLKB, 1: MTCLKC and MTCLKD + */ +#define RZ_MTU3_TMDR3_PHCKSEL (1) + +#define RZ_MTU3_16_BIT_MTU1_CH (0) +#define RZ_MTU3_16_BIT_MTU2_CH (1) +#define RZ_MTU3_32_BIT_CH (2) + +#define RZ_MTU3_TIOR_NO_OUTPUT (0) /* Output prohibited */ +#define RZ_MTU3_TIOR_IC_BOTH (10) /* Input capture at both edges */ + +#define SIGNAL_A_ID (0) +#define SIGNAL_B_ID (1) +#define SIGNAL_C_ID (2) +#define SIGNAL_D_ID (3) + +#define RZ_MTU3_MAX_HW_CNTR_CHANNELS (2) +#define RZ_MTU3_MAX_LOGICAL_CNTR_CHANNELS (3) + +/** + * struct rz_mtu3_cnt - MTU3 counter private data + * + * @clk: MTU3 module clock + * @lock: Lock to prevent concurrent access for ceiling and count + * @ch: HW channels for the counters + * @count_is_enabled: Enabled state of Counter value channel + * @mtu_16bit_max: Cache for 16-bit counters + * @mtu_32bit_max: Cache for 32-bit counters + */ +struct rz_mtu3_cnt { + struct clk *clk; + struct mutex lock; + struct rz_mtu3_channel *ch; + bool count_is_enabled[RZ_MTU3_MAX_LOGICAL_CNTR_CHANNELS]; + union { + u16 mtu_16bit_max[RZ_MTU3_MAX_HW_CNTR_CHANNELS]; + u32 mtu_32bit_max; + }; +}; + +static const enum counter_function rz_mtu3_count_functions[] = { + COUNTER_FUNCTION_QUADRATURE_X4, + COUNTER_FUNCTION_PULSE_DIRECTION, + COUNTER_FUNCTION_QUADRATURE_X2_B, +}; + +static inline size_t rz_mtu3_get_hw_ch(const size_t id) +{ + return (id == RZ_MTU3_32_BIT_CH) ? 0 : id; +} + +static inline struct rz_mtu3_channel *rz_mtu3_get_ch(struct counter_device *counter, int id) +{ + struct rz_mtu3_cnt *const priv = counter_priv(counter); + const size_t ch_id = rz_mtu3_get_hw_ch(id); + + return &priv->ch[ch_id]; +} + +static bool rz_mtu3_is_counter_invalid(struct counter_device *counter, int id) +{ + struct rz_mtu3_cnt *const priv = counter_priv(counter); + unsigned long tmdr; + + pm_runtime_get_sync(priv->ch->dev); + tmdr = rz_mtu3_shared_reg_read(priv->ch, RZ_MTU3_TMDR3); + pm_runtime_put(priv->ch->dev); + + if (id == RZ_MTU3_32_BIT_CH && test_bit(RZ_MTU3_TMDR3_LWA, &tmdr)) + return false; + + if (id != RZ_MTU3_32_BIT_CH && !test_bit(RZ_MTU3_TMDR3_LWA, &tmdr)) + return false; + + return true; +} + +static int rz_mtu3_lock_if_counter_is_valid(struct counter_device *counter, + struct rz_mtu3_channel *const ch, + struct rz_mtu3_cnt *const priv, + int id) +{ + mutex_lock(&priv->lock); + + if (ch->is_busy && !priv->count_is_enabled[id]) { + mutex_unlock(&priv->lock); + return -EINVAL; + } + + if (rz_mtu3_is_counter_invalid(counter, id)) { + mutex_unlock(&priv->lock); + return -EBUSY; + } + + return 0; +} + +static int rz_mtu3_lock_if_count_is_enabled(struct rz_mtu3_channel *const ch, + struct rz_mtu3_cnt *const priv, + int id) +{ + mutex_lock(&priv->lock); + + if (ch->is_busy && !priv->count_is_enabled[id]) { + mutex_unlock(&priv->lock); + return -EINVAL; + } + + return 0; +} + +static int rz_mtu3_count_read(struct counter_device *counter, + struct counter_count *count, u64 *val) +{ + struct rz_mtu3_channel *const ch = rz_mtu3_get_ch(counter, count->id); + struct rz_mtu3_cnt *const priv = counter_priv(counter); + int ret; + + ret = rz_mtu3_lock_if_counter_is_valid(counter, ch, priv, count->id); + if (ret) + return ret; + + pm_runtime_get_sync(ch->dev); + if (count->id == RZ_MTU3_32_BIT_CH) + *val = rz_mtu3_32bit_ch_read(ch, RZ_MTU3_TCNTLW); + else + *val = rz_mtu3_16bit_ch_read(ch, RZ_MTU3_TCNT); + pm_runtime_put(ch->dev); + mutex_unlock(&priv->lock); + + return 0; +} + +static int rz_mtu3_count_write(struct counter_device *counter, + struct counter_count *count, const u64 val) +{ + struct rz_mtu3_channel *const ch = rz_mtu3_get_ch(counter, count->id); + struct rz_mtu3_cnt *const priv = counter_priv(counter); + int ret; + + ret = rz_mtu3_lock_if_counter_is_valid(counter, ch, priv, count->id); + if (ret) + return ret; + + pm_runtime_get_sync(ch->dev); + if (count->id == RZ_MTU3_32_BIT_CH) + rz_mtu3_32bit_ch_write(ch, RZ_MTU3_TCNTLW, val); + else + rz_mtu3_16bit_ch_write(ch, RZ_MTU3_TCNT, val); + pm_runtime_put(ch->dev); + mutex_unlock(&priv->lock); + + return 0; +} + +static int rz_mtu3_count_function_read_helper(struct rz_mtu3_channel *const ch, + struct rz_mtu3_cnt *const priv, + enum counter_function *function) +{ + u8 timer_mode; + + pm_runtime_get_sync(ch->dev); + timer_mode = rz_mtu3_8bit_ch_read(ch, RZ_MTU3_TMDR1); + pm_runtime_put(ch->dev); + + switch (timer_mode & RZ_MTU3_TMDR1_PH_CNT_MODE_MASK) { + case RZ_MTU3_TMDR1_PH_CNT_MODE_1: + *function = COUNTER_FUNCTION_QUADRATURE_X4; + return 0; + case RZ_MTU3_TMDR1_PH_CNT_MODE_2: + *function = COUNTER_FUNCTION_PULSE_DIRECTION; + return 0; + case RZ_MTU3_TMDR1_PH_CNT_MODE_4: + *function = COUNTER_FUNCTION_QUADRATURE_X2_B; + return 0; + default: + /* + * TODO: + * - need to add RZ_MTU3_TMDR1_PH_CNT_MODE_3 + * - need to add RZ_MTU3_TMDR1_PH_CNT_MODE_5 + */ + return -EINVAL; + } +} + +static int rz_mtu3_count_function_read(struct counter_device *counter, + struct counter_count *count, + enum counter_function *function) +{ + struct rz_mtu3_channel *const ch = rz_mtu3_get_ch(counter, count->id); + struct rz_mtu3_cnt *const priv = counter_priv(counter); + int ret; + + ret = rz_mtu3_lock_if_count_is_enabled(ch, priv, count->id); + if (ret) + return ret; + + ret = rz_mtu3_count_function_read_helper(ch, priv, function); + mutex_unlock(&priv->lock); + + return ret; +} + +static int rz_mtu3_count_function_write(struct counter_device *counter, + struct counter_count *count, + enum counter_function function) +{ + struct rz_mtu3_channel *const ch = rz_mtu3_get_ch(counter, count->id); + struct rz_mtu3_cnt *const priv = counter_priv(counter); + u8 timer_mode; + int ret; + + ret = rz_mtu3_lock_if_count_is_enabled(ch, priv, count->id); + if (ret) + return ret; + + switch (function) { + case COUNTER_FUNCTION_QUADRATURE_X4: + timer_mode = RZ_MTU3_TMDR1_PH_CNT_MODE_1; + break; + case COUNTER_FUNCTION_PULSE_DIRECTION: + timer_mode = RZ_MTU3_TMDR1_PH_CNT_MODE_2; + break; + case COUNTER_FUNCTION_QUADRATURE_X2_B: + timer_mode = RZ_MTU3_TMDR1_PH_CNT_MODE_4; + break; + default: + /* + * TODO: + * - need to add RZ_MTU3_TMDR1_PH_CNT_MODE_3 + * - need to add RZ_MTU3_TMDR1_PH_CNT_MODE_5 + */ + mutex_unlock(&priv->lock); + return -EINVAL; + } + + pm_runtime_get_sync(ch->dev); + rz_mtu3_8bit_ch_write(ch, RZ_MTU3_TMDR1, timer_mode); + pm_runtime_put(ch->dev); + mutex_unlock(&priv->lock); + + return 0; +} + +static int rz_mtu3_count_direction_read(struct counter_device *counter, + struct counter_count *count, + enum counter_count_direction *direction) +{ + struct rz_mtu3_channel *const ch = rz_mtu3_get_ch(counter, count->id); + struct rz_mtu3_cnt *const priv = counter_priv(counter); + int ret; + u8 tsr; + + ret = rz_mtu3_lock_if_count_is_enabled(ch, priv, count->id); + if (ret) + return ret; + + pm_runtime_get_sync(ch->dev); + tsr = rz_mtu3_8bit_ch_read(ch, RZ_MTU3_TSR); + pm_runtime_put(ch->dev); + + *direction = (tsr & RZ_MTU3_TSR_TCFD) ? + COUNTER_COUNT_DIRECTION_FORWARD : COUNTER_COUNT_DIRECTION_BACKWARD; + mutex_unlock(&priv->lock); + + return 0; +} + +static int rz_mtu3_count_ceiling_read(struct counter_device *counter, + struct counter_count *count, + u64 *ceiling) +{ + struct rz_mtu3_channel *const ch = rz_mtu3_get_ch(counter, count->id); + struct rz_mtu3_cnt *const priv = counter_priv(counter); + const size_t ch_id = rz_mtu3_get_hw_ch(count->id); + int ret; + + ret = rz_mtu3_lock_if_counter_is_valid(counter, ch, priv, count->id); + if (ret) + return ret; + + switch (count->id) { + case RZ_MTU3_16_BIT_MTU1_CH: + case RZ_MTU3_16_BIT_MTU2_CH: + *ceiling = priv->mtu_16bit_max[ch_id]; + break; + case RZ_MTU3_32_BIT_CH: + *ceiling = priv->mtu_32bit_max; + break; + default: + /* should never reach this path */ + mutex_unlock(&priv->lock); + return -EINVAL; + } + + mutex_unlock(&priv->lock); + return 0; +} + +static int rz_mtu3_count_ceiling_write(struct counter_device *counter, + struct counter_count *count, + u64 ceiling) +{ + struct rz_mtu3_channel *const ch = rz_mtu3_get_ch(counter, count->id); + struct rz_mtu3_cnt *const priv = counter_priv(counter); + const size_t ch_id = rz_mtu3_get_hw_ch(count->id); + int ret; + + ret = rz_mtu3_lock_if_counter_is_valid(counter, ch, priv, count->id); + if (ret) + return ret; + + switch (count->id) { + case RZ_MTU3_16_BIT_MTU1_CH: + case RZ_MTU3_16_BIT_MTU2_CH: + if (ceiling > U16_MAX) + return -ERANGE; + priv->mtu_16bit_max[ch_id] = ceiling; + break; + case RZ_MTU3_32_BIT_CH: + if (ceiling > U32_MAX) + return -ERANGE; + priv->mtu_32bit_max = ceiling; + break; + default: + /* should never reach this path */ + mutex_unlock(&priv->lock); + return -EINVAL; + } + + pm_runtime_get_sync(ch->dev); + if (count->id == RZ_MTU3_32_BIT_CH) + rz_mtu3_32bit_ch_write(ch, RZ_MTU3_TGRALW, ceiling); + else + rz_mtu3_16bit_ch_write(ch, RZ_MTU3_TGRA, ceiling); + + rz_mtu3_8bit_ch_write(ch, RZ_MTU3_TCR, RZ_MTU3_TCR_CCLR_TGRA); + pm_runtime_put(ch->dev); + mutex_unlock(&priv->lock); + + return 0; +} + +static void rz_mtu3_32bit_cnt_setting(struct counter_device *counter) +{ + struct rz_mtu3_channel *const ch1 = rz_mtu3_get_ch(counter, 0); + struct rz_mtu3_channel *const ch2 = rz_mtu3_get_ch(counter, 1); + + /* Phase counting mode 1 is used as default in initialization. */ + rz_mtu3_8bit_ch_write(ch1, RZ_MTU3_TMDR1, RZ_MTU3_TMDR1_PH_CNT_MODE_1); + + rz_mtu3_8bit_ch_write(ch1, RZ_MTU3_TCR, RZ_MTU3_TCR_CCLR_TGRA); + rz_mtu3_8bit_ch_write(ch1, RZ_MTU3_TIOR, RZ_MTU3_TIOR_IC_BOTH); + + rz_mtu3_enable(ch1); + rz_mtu3_enable(ch2); +} + +static void rz_mtu3_16bit_cnt_setting(struct counter_device *counter, int id) +{ + struct rz_mtu3_channel *const ch = rz_mtu3_get_ch(counter, id); + + /* Phase counting mode 1 is used as default in initialization. */ + rz_mtu3_8bit_ch_write(ch, RZ_MTU3_TMDR1, RZ_MTU3_TMDR1_PH_CNT_MODE_1); + + rz_mtu3_8bit_ch_write(ch, RZ_MTU3_TCR, RZ_MTU3_TCR_CCLR_TGRA); + rz_mtu3_8bit_ch_write(ch, RZ_MTU3_TIOR, RZ_MTU3_TIOR_NO_OUTPUT); + rz_mtu3_enable(ch); +} + +static int rz_mtu3_initialize_counter(struct counter_device *counter, int id) +{ + struct rz_mtu3_channel *const ch = rz_mtu3_get_ch(counter, id); + struct rz_mtu3_channel *const ch1 = rz_mtu3_get_ch(counter, 0); + struct rz_mtu3_channel *const ch2 = rz_mtu3_get_ch(counter, 1); + + switch (id) { + case RZ_MTU3_16_BIT_MTU1_CH: + case RZ_MTU3_16_BIT_MTU2_CH: + if (!rz_mtu3_request_channel(ch)) + return -EBUSY; + + rz_mtu3_16bit_cnt_setting(counter, id); + return 0; + case RZ_MTU3_32_BIT_CH: + /* + * 32-bit phase counting need MTU1 and MTU2 to create 32-bit + * cascade counter. + */ + if (!rz_mtu3_request_channel(ch1)) + return -EBUSY; + + if (!rz_mtu3_request_channel(ch2)) { + rz_mtu3_release_channel(ch1); + return -EBUSY; + } + + rz_mtu3_32bit_cnt_setting(counter); + return 0; + default: + /* should never reach this path */ + return -EINVAL; + } +} + +static void rz_mtu3_terminate_counter(struct counter_device *counter, int id) +{ + struct rz_mtu3_channel *const ch = rz_mtu3_get_ch(counter, id); + struct rz_mtu3_channel *const ch1 = rz_mtu3_get_ch(counter, 0); + struct rz_mtu3_channel *const ch2 = rz_mtu3_get_ch(counter, 1); + + if (id == RZ_MTU3_32_BIT_CH) { + rz_mtu3_release_channel(ch2); + rz_mtu3_release_channel(ch1); + rz_mtu3_disable(ch2); + rz_mtu3_disable(ch1); + } else { + rz_mtu3_release_channel(ch); + rz_mtu3_disable(ch); + } +} + +static int rz_mtu3_count_enable_read(struct counter_device *counter, + struct counter_count *count, u8 *enable) +{ + struct rz_mtu3_channel *const ch = rz_mtu3_get_ch(counter, count->id); + struct rz_mtu3_channel *const ch1 = rz_mtu3_get_ch(counter, 0); + struct rz_mtu3_channel *const ch2 = rz_mtu3_get_ch(counter, 1); + struct rz_mtu3_cnt *const priv = counter_priv(counter); + int ret; + + ret = rz_mtu3_lock_if_count_is_enabled(ch, priv, count->id); + if (ret) + return ret; + + if (count->id == RZ_MTU3_32_BIT_CH) + *enable = rz_mtu3_is_enabled(ch1) && rz_mtu3_is_enabled(ch2); + else + *enable = rz_mtu3_is_enabled(ch); + + mutex_unlock(&priv->lock); + + return 0; +} + +static int rz_mtu3_count_enable_write(struct counter_device *counter, + struct counter_count *count, u8 enable) +{ + struct rz_mtu3_channel *const ch = rz_mtu3_get_ch(counter, count->id); + struct rz_mtu3_cnt *const priv = counter_priv(counter); + int ret = 0; + + if (enable) { + pm_runtime_get_sync(ch->dev); + mutex_lock(&priv->lock); + ret = rz_mtu3_initialize_counter(counter, count->id); + if (ret == 0) + priv->count_is_enabled[count->id] = true; + mutex_unlock(&priv->lock); + } else { + mutex_lock(&priv->lock); + rz_mtu3_terminate_counter(counter, count->id); + priv->count_is_enabled[count->id] = false; + mutex_unlock(&priv->lock); + pm_runtime_put(ch->dev); + } + + return ret; +} + +static int rz_mtu3_lock_if_ch0_is_enabled(struct rz_mtu3_cnt *const priv) +{ + mutex_lock(&priv->lock); + if (priv->ch->is_busy && !(priv->count_is_enabled[RZ_MTU3_16_BIT_MTU1_CH] || + priv->count_is_enabled[RZ_MTU3_32_BIT_CH])) { + mutex_unlock(&priv->lock); + return -EINVAL; + } + + return 0; +} + +static int rz_mtu3_cascade_counts_enable_get(struct counter_device *counter, + u8 *cascade_enable) +{ + struct rz_mtu3_cnt *const priv = counter_priv(counter); + unsigned long tmdr; + int ret; + + ret = rz_mtu3_lock_if_ch0_is_enabled(priv); + if (ret) + return ret; + + pm_runtime_get_sync(priv->ch->dev); + tmdr = rz_mtu3_shared_reg_read(priv->ch, RZ_MTU3_TMDR3); + pm_runtime_put(priv->ch->dev); + *cascade_enable = test_bit(RZ_MTU3_TMDR3_LWA, &tmdr); + mutex_unlock(&priv->lock); + + return 0; +} + +static int rz_mtu3_cascade_counts_enable_set(struct counter_device *counter, + u8 cascade_enable) +{ + struct rz_mtu3_cnt *const priv = counter_priv(counter); + int ret; + + ret = rz_mtu3_lock_if_ch0_is_enabled(priv); + if (ret) + return ret; + + pm_runtime_get_sync(priv->ch->dev); + rz_mtu3_shared_reg_update_bit(priv->ch, RZ_MTU3_TMDR3, + RZ_MTU3_TMDR3_LWA, cascade_enable); + pm_runtime_put(priv->ch->dev); + mutex_unlock(&priv->lock); + + return 0; +} + +static int rz_mtu3_ext_input_phase_clock_select_get(struct counter_device *counter, + u32 *ext_input_phase_clock_select) +{ + struct rz_mtu3_cnt *const priv = counter_priv(counter); + unsigned long tmdr; + int ret; + + ret = rz_mtu3_lock_if_ch0_is_enabled(priv); + if (ret) + return ret; + + pm_runtime_get_sync(priv->ch->dev); + tmdr = rz_mtu3_shared_reg_read(priv->ch, RZ_MTU3_TMDR3); + pm_runtime_put(priv->ch->dev); + *ext_input_phase_clock_select = test_bit(RZ_MTU3_TMDR3_PHCKSEL, &tmdr); + mutex_unlock(&priv->lock); + + return 0; +} + +static int rz_mtu3_ext_input_phase_clock_select_set(struct counter_device *counter, + u32 ext_input_phase_clock_select) +{ + struct rz_mtu3_cnt *const priv = counter_priv(counter); + int ret; + + ret = rz_mtu3_lock_if_ch0_is_enabled(priv); + if (ret) + return ret; + + pm_runtime_get_sync(priv->ch->dev); + rz_mtu3_shared_reg_update_bit(priv->ch, RZ_MTU3_TMDR3, + RZ_MTU3_TMDR3_PHCKSEL, + ext_input_phase_clock_select); + pm_runtime_put(priv->ch->dev); + mutex_unlock(&priv->lock); + + return 0; +} + +static struct counter_comp rz_mtu3_count_ext[] = { + COUNTER_COMP_DIRECTION(rz_mtu3_count_direction_read), + COUNTER_COMP_ENABLE(rz_mtu3_count_enable_read, + rz_mtu3_count_enable_write), + COUNTER_COMP_CEILING(rz_mtu3_count_ceiling_read, + rz_mtu3_count_ceiling_write), +}; + +static const enum counter_synapse_action rz_mtu3_synapse_actions[] = { + COUNTER_SYNAPSE_ACTION_BOTH_EDGES, + COUNTER_SYNAPSE_ACTION_RISING_EDGE, + COUNTER_SYNAPSE_ACTION_NONE, +}; + +static int rz_mtu3_action_read(struct counter_device *counter, + struct counter_count *count, + struct counter_synapse *synapse, + enum counter_synapse_action *action) +{ + const bool is_signal_ab = (synapse->signal->id == SIGNAL_A_ID) || + (synapse->signal->id == SIGNAL_B_ID); + struct rz_mtu3_channel *const ch = rz_mtu3_get_ch(counter, count->id); + struct rz_mtu3_cnt *const priv = counter_priv(counter); + enum counter_function function; + bool mtclkc_mtclkd; + unsigned long tmdr; + int ret; + + ret = rz_mtu3_lock_if_count_is_enabled(ch, priv, count->id); + if (ret) + return ret; + + ret = rz_mtu3_count_function_read_helper(ch, priv, &function); + if (ret) { + mutex_unlock(&priv->lock); + return ret; + } + + /* Default action mode */ + *action = COUNTER_SYNAPSE_ACTION_NONE; + + if (count->id != RZ_MTU3_16_BIT_MTU1_CH) { + tmdr = rz_mtu3_shared_reg_read(priv->ch, RZ_MTU3_TMDR3); + mtclkc_mtclkd = test_bit(RZ_MTU3_TMDR3_PHCKSEL, &tmdr); + if ((mtclkc_mtclkd && is_signal_ab) || + (!mtclkc_mtclkd && !is_signal_ab)) { + mutex_unlock(&priv->lock); + return 0; + } + } + + switch (function) { + case COUNTER_FUNCTION_PULSE_DIRECTION: + /* + * Rising edges on signal A (signal C) updates the respective + * count. The input level of signal B (signal D) determines + * direction. + */ + if (synapse->signal->id == SIGNAL_A_ID || + synapse->signal->id == SIGNAL_C_ID) + *action = COUNTER_SYNAPSE_ACTION_RISING_EDGE; + break; + case COUNTER_FUNCTION_QUADRATURE_X2_B: + /* + * Any state transition on quadrature pair signal B (signal D) + * updates the respective count. + */ + if (synapse->signal->id == SIGNAL_B_ID || + synapse->signal->id == SIGNAL_D_ID) + *action = COUNTER_SYNAPSE_ACTION_BOTH_EDGES; + break; + case COUNTER_FUNCTION_QUADRATURE_X4: + /* counts up/down on both edges of A (C) and B (D) signal */ + *action = COUNTER_SYNAPSE_ACTION_BOTH_EDGES; + break; + default: + /* should never reach this path */ + mutex_unlock(&priv->lock); + return -EINVAL; + } + + mutex_unlock(&priv->lock); + + return 0; +} + +static const struct counter_ops rz_mtu3_cnt_ops = { + .count_read = rz_mtu3_count_read, + .count_write = rz_mtu3_count_write, + .function_read = rz_mtu3_count_function_read, + .function_write = rz_mtu3_count_function_write, + .action_read = rz_mtu3_action_read, +}; + +#define RZ_MTU3_PHASE_SIGNAL(_id, _name) { \ + .id = (_id), \ + .name = (_name), \ +} + +static struct counter_signal rz_mtu3_signals[] = { + RZ_MTU3_PHASE_SIGNAL(SIGNAL_A_ID, "MTU1 MTCLKA"), + RZ_MTU3_PHASE_SIGNAL(SIGNAL_B_ID, "MTU1 MTCLKB"), + RZ_MTU3_PHASE_SIGNAL(SIGNAL_C_ID, "MTU2 MTCLKC"), + RZ_MTU3_PHASE_SIGNAL(SIGNAL_D_ID, "MTU2 MTCLKD"), +}; + +static struct counter_synapse rz_mtu3_mtu1_count_synapses[] = { + { + .actions_list = rz_mtu3_synapse_actions, + .num_actions = ARRAY_SIZE(rz_mtu3_synapse_actions), + .signal = rz_mtu3_signals, + }, + { + .actions_list = rz_mtu3_synapse_actions, + .num_actions = ARRAY_SIZE(rz_mtu3_synapse_actions), + .signal = rz_mtu3_signals + 1, + } +}; + +static struct counter_synapse rz_mtu3_mtu2_count_synapses[] = { + { + .actions_list = rz_mtu3_synapse_actions, + .num_actions = ARRAY_SIZE(rz_mtu3_synapse_actions), + .signal = rz_mtu3_signals, + }, + { + .actions_list = rz_mtu3_synapse_actions, + .num_actions = ARRAY_SIZE(rz_mtu3_synapse_actions), + .signal = rz_mtu3_signals + 1, + }, + { + .actions_list = rz_mtu3_synapse_actions, + .num_actions = ARRAY_SIZE(rz_mtu3_synapse_actions), + .signal = rz_mtu3_signals + 2, + }, + { + .actions_list = rz_mtu3_synapse_actions, + .num_actions = ARRAY_SIZE(rz_mtu3_synapse_actions), + .signal = rz_mtu3_signals + 3, + } +}; + +static struct counter_count rz_mtu3_counts[] = { + { + .id = RZ_MTU3_16_BIT_MTU1_CH, + .name = "Channel 1 Count", + .functions_list = rz_mtu3_count_functions, + .num_functions = ARRAY_SIZE(rz_mtu3_count_functions), + .synapses = rz_mtu3_mtu1_count_synapses, + .num_synapses = ARRAY_SIZE(rz_mtu3_mtu1_count_synapses), + .ext = rz_mtu3_count_ext, + .num_ext = ARRAY_SIZE(rz_mtu3_count_ext), + }, + { + .id = RZ_MTU3_16_BIT_MTU2_CH, + .name = "Channel 2 Count", + .functions_list = rz_mtu3_count_functions, + .num_functions = ARRAY_SIZE(rz_mtu3_count_functions), + .synapses = rz_mtu3_mtu2_count_synapses, + .num_synapses = ARRAY_SIZE(rz_mtu3_mtu2_count_synapses), + .ext = rz_mtu3_count_ext, + .num_ext = ARRAY_SIZE(rz_mtu3_count_ext), + }, + { + .id = RZ_MTU3_32_BIT_CH, + .name = "Channel 1 and 2 (cascaded) Count", + .functions_list = rz_mtu3_count_functions, + .num_functions = ARRAY_SIZE(rz_mtu3_count_functions), + .synapses = rz_mtu3_mtu2_count_synapses, + .num_synapses = ARRAY_SIZE(rz_mtu3_mtu2_count_synapses), + .ext = rz_mtu3_count_ext, + .num_ext = ARRAY_SIZE(rz_mtu3_count_ext), + } +}; + +static const char *const rz_mtu3_ext_input_phase_clock_select[] = { + "MTCLKA-MTCLKB", + "MTCLKC-MTCLKD", +}; + +static DEFINE_COUNTER_ENUM(rz_mtu3_ext_input_phase_clock_select_enum, + rz_mtu3_ext_input_phase_clock_select); + +static struct counter_comp rz_mtu3_device_ext[] = { + COUNTER_COMP_DEVICE_BOOL("cascade_counts_enable", + rz_mtu3_cascade_counts_enable_get, + rz_mtu3_cascade_counts_enable_set), + COUNTER_COMP_DEVICE_ENUM("external_input_phase_clock_select", + rz_mtu3_ext_input_phase_clock_select_get, + rz_mtu3_ext_input_phase_clock_select_set, + rz_mtu3_ext_input_phase_clock_select_enum), +}; + +static int rz_mtu3_cnt_pm_runtime_suspend(struct device *dev) +{ + struct clk *const clk = dev_get_drvdata(dev); + + clk_disable_unprepare(clk); + + return 0; +} + +static int rz_mtu3_cnt_pm_runtime_resume(struct device *dev) +{ + struct clk *const clk = dev_get_drvdata(dev); + + clk_prepare_enable(clk); + + return 0; +} + +static DEFINE_RUNTIME_DEV_PM_OPS(rz_mtu3_cnt_pm_ops, + rz_mtu3_cnt_pm_runtime_suspend, + rz_mtu3_cnt_pm_runtime_resume, NULL); + +static void rz_mtu3_cnt_pm_disable(void *data) +{ + struct device *dev = data; + + pm_runtime_disable(dev); + pm_runtime_set_suspended(dev); +} + +static int rz_mtu3_cnt_probe(struct platform_device *pdev) +{ + struct rz_mtu3 *ddata = dev_get_drvdata(pdev->dev.parent); + struct device *dev = &pdev->dev; + struct counter_device *counter; + struct rz_mtu3_channel *ch; + struct rz_mtu3_cnt *priv; + unsigned int i; + int ret; + + counter = devm_counter_alloc(dev, sizeof(*priv)); + if (!counter) + return -ENOMEM; + + priv = counter_priv(counter); + priv->clk = ddata->clk; + priv->mtu_32bit_max = U32_MAX; + priv->ch = &ddata->channels[RZ_MTU1]; + ch = &priv->ch[0]; + for (i = 0; i < RZ_MTU3_MAX_HW_CNTR_CHANNELS; i++) { + ch->dev = dev; + priv->mtu_16bit_max[i] = U16_MAX; + ch++; + } + + mutex_init(&priv->lock); + platform_set_drvdata(pdev, priv->clk); + clk_prepare_enable(priv->clk); + pm_runtime_set_active(&pdev->dev); + pm_runtime_enable(&pdev->dev); + ret = devm_add_action_or_reset(&pdev->dev, rz_mtu3_cnt_pm_disable, dev); + if (ret < 0) + goto disable_clock; + + counter->name = dev_name(dev); + counter->parent = dev; + counter->ops = &rz_mtu3_cnt_ops; + counter->counts = rz_mtu3_counts; + counter->num_counts = ARRAY_SIZE(rz_mtu3_counts); + counter->signals = rz_mtu3_signals; + counter->num_signals = ARRAY_SIZE(rz_mtu3_signals); + counter->ext = rz_mtu3_device_ext; + counter->num_ext = ARRAY_SIZE(rz_mtu3_device_ext); + + /* Register Counter device */ + ret = devm_counter_add(dev, counter); + if (ret < 0) { + dev_err_probe(dev, ret, "Failed to add counter\n"); + goto disable_clock; + } + + return 0; + +disable_clock: + clk_disable_unprepare(priv->clk); + + return ret; +} + +static struct platform_driver rz_mtu3_cnt_driver = { + .probe = rz_mtu3_cnt_probe, + .driver = { + .name = "rz-mtu3-counter", + .pm = pm_ptr(&rz_mtu3_cnt_pm_ops), + }, +}; +module_platform_driver(rz_mtu3_cnt_driver); + +MODULE_AUTHOR("Biju Das "); +MODULE_ALIAS("platform:rz-mtu3-counter"); +MODULE_DESCRIPTION("Renesas RZ/G2L MTU3a counter driver"); +MODULE_LICENSE("GPL"); +MODULE_IMPORT_NS(COUNTER);