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Wed, 24 Jan 2024 23:21:28 -0800 (PST) Received: from localhost.localdomain ([188.162.200.139]) by smtp.gmail.com with ESMTPSA id x37-20020a056512132500b0050e75f9e8c8sm2780070lfu.98.2024.01.24.23.21.26 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Wed, 24 Jan 2024 23:21:28 -0800 (PST) From: Aleksandr Shubin To: linux-kernel@vger.kernel.org Subject: [PATCH v7 1/3] dt-bindings: pwm: Add binding for Allwinner D1/T113-S3/R329 PWM controller Date: Thu, 25 Jan 2024 10:19:41 +0300 Message-Id: <20240125072032.1151383-2-privatesub2@gmail.com> X-Mailer: git-send-email 2.25.1 In-Reply-To: <20240125072032.1151383-1-privatesub2@gmail.com> References: <20240125072032.1151383-1-privatesub2@gmail.com> MIME-Version: 1.0 X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20240124_232131_207526_ECAFF5CB X-CRM114-Status: GOOD ( 15.40 ) X-BeenThere: linux-riscv@lists.infradead.org X-Mailman-Version: 2.1.34 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: devicetree@vger.kernel.org, Conor Dooley , John Watts , Krzysztof Kozlowski , linux-riscv@lists.infradead.org, Samuel Holland , Albert Ou , Jernej Skrabec , Chen-Yu Tsai , =?utf-8?q?Uwe_Kleine-K=C3=B6nig?= , linux-sunxi@lists.linux.dev, linux-pwm@vger.kernel.org, Conor Dooley , Aleksandr Shubin , Rob Herring , Marc Kleine-Budde , Paul Walmsley , Maksim Kiselev , linux-arm-kernel@lists.infradead.org, Cheo Fusi , Palmer Dabbelt , Philipp Zabel Sender: "linux-riscv" Errors-To: linux-riscv-bounces+linux-riscv=archiver.kernel.org@lists.infradead.org Allwinner's D1, T113-S3 and R329 SoCs have a new pwm controller witch is different from the previous pwm-sun4i. The D1 and T113 are identical in terms of peripherals, they differ only in the architecture of the CPU core, and even share the majority of their DT. Because of that, using the same compatible makes sense. The R329 is a different SoC though, and should have a different compatible string added, especially as there is a difference in the number of channels. D1 and T113s SoCs have one PWM controller with 8 channels. R329 SoC has two PWM controllers in both power domains, one of them has 9 channels (CPUX one) and the other has 6 (CPUS one). Add a device tree binding for them. Signed-off-by: Aleksandr Shubin Reviewed-by: Conor Dooley --- .../bindings/pwm/allwinner,sun20i-pwm.yaml | 88 +++++++++++++++++++ 1 file changed, 88 insertions(+) create mode 100644 Documentation/devicetree/bindings/pwm/allwinner,sun20i-pwm.yaml diff --git a/Documentation/devicetree/bindings/pwm/allwinner,sun20i-pwm.yaml b/Documentation/devicetree/bindings/pwm/allwinner,sun20i-pwm.yaml new file mode 100644 index 000000000000..716f75776006 --- /dev/null +++ b/Documentation/devicetree/bindings/pwm/allwinner,sun20i-pwm.yaml @@ -0,0 +1,88 @@ +# SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause) +%YAML 1.2 +--- +$id: http://devicetree.org/schemas/pwm/allwinner,sun20i-pwm.yaml# +$schema: http://devicetree.org/meta-schemas/core.yaml# + +title: Allwinner D1, T113-S3 and R329 PWM + +maintainers: + - Aleksandr Shubin + - Brandon Cheo Fusi + +properties: + compatible: + oneOf: + - const: allwinner,sun20i-d1-pwm + - items: + - const: allwinner,sun20i-r329-pwm + - const: allwinner,sun20i-d1-pwm + + reg: + maxItems: 1 + + "#pwm-cells": + const: 3 + + clocks: + items: + - description: Bus clock + - description: 24 MHz oscillator + - description: APB0 clock + + clock-names: + items: + - const: bus + - const: hosc + - const: apb0 + + resets: + maxItems: 1 + + allwinner,pwm-channels: + $ref: /schemas/types.yaml#/definitions/uint32 + description: The number of PWM channels configured for this instance + enum: [6, 9] + +allOf: + - $ref: pwm.yaml# + + - if: + properties: + compatible: + contains: + const: allwinner,sun20i-r329-pwm + + then: + required: + - allwinner,pwm-channels + + else: + properties: + allwinner,pwm-channels: false + +unevaluatedProperties: false + +required: + - compatible + - reg + - "#pwm-cells" + - clocks + - clock-names + - resets + +examples: + - | + #include + #include + + pwm: pwm@2000c00 { + compatible = "allwinner,sun20i-d1-pwm"; + reg = <0x02000c00 0x400>; + clocks = <&ccu CLK_BUS_PWM>, <&dcxo>, <&ccu CLK_APB0>; + clock-names = "bus", "hosc", "apb0"; + resets = <&ccu RST_BUS_PWM>; + #pwm-cells = <0x3>; + }; + +... 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Wed, 24 Jan 2024 23:21:41 -0800 (PST) Received: from localhost.localdomain ([188.162.200.139]) by smtp.gmail.com with ESMTPSA id x37-20020a056512132500b0050e75f9e8c8sm2780070lfu.98.2024.01.24.23.21.39 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Wed, 24 Jan 2024 23:21:41 -0800 (PST) From: Aleksandr Shubin To: linux-kernel@vger.kernel.org Subject: [PATCH v7 2/3] pwm: Add Allwinner's D1/T113-S3/R329 SoCs PWM support Date: Thu, 25 Jan 2024 10:19:42 +0300 Message-Id: <20240125072032.1151383-3-privatesub2@gmail.com> X-Mailer: git-send-email 2.25.1 In-Reply-To: <20240125072032.1151383-1-privatesub2@gmail.com> References: <20240125072032.1151383-1-privatesub2@gmail.com> MIME-Version: 1.0 X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20240124_232144_429147_26FE1F8D X-CRM114-Status: GOOD ( 31.41 ) X-BeenThere: linux-riscv@lists.infradead.org X-Mailman-Version: 2.1.34 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: devicetree@vger.kernel.org, John Watts , Krzysztof Kozlowski , linux-riscv@lists.infradead.org, Samuel Holland , Albert Ou , Jernej Skrabec , Chen-Yu Tsai , =?utf-8?q?Uwe_Kleine-K=C3=B6nig?= , linux-sunxi@lists.linux.dev, linux-pwm@vger.kernel.org, Conor Dooley , Aleksandr Shubin , Rob Herring , Marc Kleine-Budde , Paul Walmsley , Maksim Kiselev , linux-arm-kernel@lists.infradead.org, Brandon Cheo Fusi , Palmer Dabbelt , Philipp Zabel Sender: "linux-riscv" Errors-To: linux-riscv-bounces+linux-riscv=archiver.kernel.org@lists.infradead.org Allwinner's D1, T113-S3 and R329 SoCs have a quite different PWM controllers with ones supported by pwm-sun4i driver. This patch adds a PWM controller driver for Allwinner's D1, T113-S3 and R329 SoCs. The main difference between these SoCs is the number of channels defined by the DT property. Co-developed-by: Brandon Cheo Fusi Signed-off-by: Brandon Cheo Fusi Signed-off-by: Aleksandr Shubin --- drivers/pwm/Kconfig | 10 ++ drivers/pwm/Makefile | 1 + drivers/pwm/pwm-sun20i.c | 380 +++++++++++++++++++++++++++++++++++++++ 3 files changed, 391 insertions(+) create mode 100644 drivers/pwm/pwm-sun20i.c diff --git a/drivers/pwm/Kconfig b/drivers/pwm/Kconfig index 4b956d661755..d2e0a080eb3c 100644 --- a/drivers/pwm/Kconfig +++ b/drivers/pwm/Kconfig @@ -625,6 +625,16 @@ config PWM_SUN4I To compile this driver as a module, choose M here: the module will be called pwm-sun4i. +config PWM_SUN20I + tristate "Allwinner D1/T113s/R329 PWM support" + depends on ARCH_SUNXI || COMPILE_TEST + depends on COMMON_CLK + help + Generic PWM framework driver for Allwinner D1/T113s/R329 SoCs. + + To compile this driver as a module, choose M here: the module + will be called pwm-sun20i. + config PWM_SUNPLUS tristate "Sunplus PWM support" depends on ARCH_SUNPLUS || COMPILE_TEST diff --git a/drivers/pwm/Makefile b/drivers/pwm/Makefile index c5ec9e168ee7..dcad0d5a2430 100644 --- a/drivers/pwm/Makefile +++ b/drivers/pwm/Makefile @@ -58,6 +58,7 @@ obj-$(CONFIG_PWM_STM32) += pwm-stm32.o obj-$(CONFIG_PWM_STM32_LP) += pwm-stm32-lp.o obj-$(CONFIG_PWM_STMPE) += pwm-stmpe.o obj-$(CONFIG_PWM_SUN4I) += pwm-sun4i.o +obj-$(CONFIG_PWM_SUN20I) += pwm-sun20i.o obj-$(CONFIG_PWM_SUNPLUS) += pwm-sunplus.o obj-$(CONFIG_PWM_TEGRA) += pwm-tegra.o obj-$(CONFIG_PWM_TIECAP) += pwm-tiecap.o diff --git a/drivers/pwm/pwm-sun20i.c b/drivers/pwm/pwm-sun20i.c new file mode 100644 index 000000000000..d9e151f27f20 --- /dev/null +++ b/drivers/pwm/pwm-sun20i.c @@ -0,0 +1,380 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * PWM Controller Driver for sunxi platforms (D1, T113-S3 and R329) + * + * Limitations: + * - When the parameters change, current running period will not be completed + * and run new settings immediately. + * - It output HIGH-Z state when PWM channel disabled. + * + * Copyright (c) 2023 Aleksandr Shubin + */ + +#include +#include +#include +#include +#include +#include +#include +#include + +#define SUN20I_PWM_CLK_CFG(chan) (0x20 + (((chan) >> 1) * 0x4)) +#define SUN20I_PWM_CLK_CFG_SRC GENMASK(8, 7) +#define SUN20I_PWM_CLK_CFG_DIV_M GENMASK(3, 0) +#define SUN20I_PWM_CLK_DIV_M_MAX 8 + +#define SUN20I_PWM_CLK_GATE 0x40 +#define SUN20I_PWM_CLK_GATE_BYPASS(chan) BIT((chan) + 16) +#define SUN20I_PWM_CLK_GATE_GATING(chan) BIT(chan) + +#define SUN20I_PWM_ENABLE 0x80 +#define SUN20I_PWM_ENABLE_EN(chan) BIT(chan) + +#define SUN20I_PWM_CTL(chan) (0x100 + (chan) * 0x20) +#define SUN20I_PWM_CTL_ACT_STA BIT(8) +#define SUN20I_PWM_CTL_PRESCAL_K GENMASK(7, 0) +#define SUN20I_PWM_CTL_PRESCAL_K_MAX 0xff + +#define SUN20I_PWM_PERIOD(chan) (0x104 + (chan) * 0x20) +#define SUN20I_PWM_PERIOD_ENTIRE_CYCLE GENMASK(31, 16) +#define SUN20I_PWM_PERIOD_ACT_CYCLE GENMASK(15, 0) + +#define SUN20I_PWM_PCNTR_SIZE BIT(16) + +/** + * SUN20I_PWM_MAGIC is used to quickly compute the values of the clock dividers + * div_m (SUN20I_PWM_CLK_CFG_DIV_M) & prescale_k (SUN20I_PWM_CTL_PRESCAL_K) + * without using a loop. These dividers limit the # of cycles in a period + * to SUN20I_PWM_PCNTR_SIZE by applying a scaling factor of + * 1/(div_m * (prescale_k + 1)) to the clock source. + * + * SUN20I_PWM_MAGIC is derived by solving for div_m and prescale_k + * such that for a given requested period, + * + * i) div_m is minimized for any prescale_k ≤ SUN20I_PWM_CTL_PRESCAL_K_MAX, + * ii) prescale_k is minimized. + * + * The derivation proceeds as follows, with val = # of cycles for reqested + * period: + * + * for a given value of div_m we want the smallest prescale_k such that + * + * (val >> div_m) // (prescale_k + 1) ≤ 65536 (SUN20I_PWM_PCNTR_SIZE) + * + * This is equivalent to: + * + * (val >> div_m) ≤ 65536 * (prescale_k + 1) + prescale_k + * ⟺ (val >> div_m) ≤ 65537 * prescale_k + 65536 + * ⟺ (val >> div_m) - 65536 ≤ 65537 * prescale_k + * ⟺ ((val >> div_m) - 65536) / 65537 ≤ prescale_k + * + * As prescale_k is integer, this becomes + * + * ((val >> div_m) - 65536) // 65537 ≤ prescale_k + * + * And is minimized at + * + * ((val >> div_m) - 65536) // 65537 + * + * Now we pick the smallest div_m that satifies prescale_k ≤ 255 + * (i.e SUN20I_PWM_CTL_PRESCAL_K_MAX), + * + * ((val >> div_m) - 65536) // 65537 ≤ 255 + * ⟺ (val >> div_m) - 65536 ≤ 255 * 65537 + 65536 + * ⟺ val >> div_m ≤ 255 * 65537 + 2 * 65536 + * ⟺ val >> div_m < (255 * 65537 + 2 * 65536 + 1) + * ⟺ div_m = fls((val) / (255 * 65537 + 2 * 65536 + 1)) + * + * Suggested by Uwe Kleine-König + */ +#define SUN20I_PWM_MAGIC (255 * 65537 + 2 * 65536 + 1) + +struct sun20i_pwm_chip { + struct clk *clk_bus, *clk_hosc, *clk_apb0; + struct reset_control *rst; + struct pwm_chip chip; + void __iomem *base; + /* Mutex to protect pwm apply state */ + struct mutex mutex; +}; + +static inline struct sun20i_pwm_chip *to_sun20i_pwm_chip(struct pwm_chip *chip) +{ + return container_of(chip, struct sun20i_pwm_chip, chip); +} + +static inline u32 sun20i_pwm_readl(struct sun20i_pwm_chip *chip, + unsigned long offset) +{ + return readl(chip->base + offset); +} + +static inline void sun20i_pwm_writel(struct sun20i_pwm_chip *chip, + u32 val, unsigned long offset) +{ + writel(val, chip->base + offset); +} + +static int sun20i_pwm_get_state(struct pwm_chip *chip, + struct pwm_device *pwm, + struct pwm_state *state) +{ + struct sun20i_pwm_chip *sun20i_chip = to_sun20i_pwm_chip(chip); + u16 ent_cycle, act_cycle, prescale_k; + u64 clk_rate, tmp; + u8 div_m; + u32 val; + + mutex_lock(&sun20i_chip->mutex); + + val = sun20i_pwm_readl(sun20i_chip, SUN20I_PWM_CLK_CFG(pwm->hwpwm)); + div_m = FIELD_GET(SUN20I_PWM_CLK_CFG_DIV_M, val); + if (div_m > SUN20I_PWM_CLK_DIV_M_MAX) + div_m = SUN20I_PWM_CLK_DIV_M_MAX; + + if (FIELD_GET(SUN20I_PWM_CLK_CFG_SRC, val) == 0) + clk_rate = clk_get_rate(sun20i_chip->clk_hosc); + else + clk_rate = clk_get_rate(sun20i_chip->clk_apb0); + + val = sun20i_pwm_readl(sun20i_chip, SUN20I_PWM_CTL(pwm->hwpwm)); + state->polarity = (SUN20I_PWM_CTL_ACT_STA & val) ? + PWM_POLARITY_NORMAL : PWM_POLARITY_INVERSED; + + prescale_k = FIELD_GET(SUN20I_PWM_CTL_PRESCAL_K, val) + 1; + + val = sun20i_pwm_readl(sun20i_chip, SUN20I_PWM_ENABLE); + state->enabled = (SUN20I_PWM_ENABLE_EN(pwm->hwpwm) & val) ? true : false; + + val = sun20i_pwm_readl(sun20i_chip, SUN20I_PWM_PERIOD(pwm->hwpwm)); + + mutex_unlock(&sun20i_chip->mutex); + + act_cycle = FIELD_GET(SUN20I_PWM_PERIOD_ACT_CYCLE, val); + ent_cycle = FIELD_GET(SUN20I_PWM_PERIOD_ENTIRE_CYCLE, val); + + /* + * The duration of the active phase should not be longer + * than the duration of the period + */ + if (act_cycle > ent_cycle) + act_cycle = ent_cycle; + + tmp = ((u64)(act_cycle) * prescale_k << div_m) * NSEC_PER_SEC; + state->duty_cycle = DIV_ROUND_UP_ULL(tmp, clk_rate); + tmp = ((u64)(ent_cycle) * prescale_k << div_m) * NSEC_PER_SEC; + state->period = DIV_ROUND_UP_ULL(tmp, clk_rate); + + return 0; +} + +static int sun20i_pwm_apply(struct pwm_chip *chip, struct pwm_device *pwm, + const struct pwm_state *state) +{ + struct sun20i_pwm_chip *sun20i_chip = to_sun20i_pwm_chip(chip); + u64 bus_rate, hosc_rate, val, ent_cycle, act_cycle; + u32 clk_gate, clk_cfg, pwm_en, ctl, reg_period; + u32 prescale_k, div_m; + bool use_bus_clk; + int ret = 0; + + mutex_lock(&sun20i_chip->mutex); + + pwm_en = sun20i_pwm_readl(sun20i_chip, SUN20I_PWM_ENABLE); + + if (state->enabled != pwm->state.enabled) { + clk_gate = sun20i_pwm_readl(sun20i_chip, SUN20I_PWM_CLK_GATE); + + if (!state->enabled) { + clk_gate &= ~SUN20I_PWM_CLK_GATE_GATING(pwm->hwpwm); + pwm_en &= ~SUN20I_PWM_ENABLE_EN(pwm->hwpwm); + sun20i_pwm_writel(sun20i_chip, pwm_en, SUN20I_PWM_ENABLE); + sun20i_pwm_writel(sun20i_chip, clk_gate, SUN20I_PWM_CLK_GATE); + } + } + + if (state->polarity != pwm->state.polarity || + state->duty_cycle != pwm->state.duty_cycle || + state->period != pwm->state.period) { + ctl = sun20i_pwm_readl(sun20i_chip, SUN20I_PWM_CTL(pwm->hwpwm)); + clk_cfg = sun20i_pwm_readl(sun20i_chip, SUN20I_PWM_CLK_CFG(pwm->hwpwm)); + hosc_rate = clk_get_rate(sun20i_chip->clk_hosc); + bus_rate = clk_get_rate(sun20i_chip->clk_apb0); + if (pwm_en & SUN20I_PWM_ENABLE_EN(pwm->hwpwm ^ 1)) { + /* if the neighbor channel is enable, check period only */ + use_bus_clk = FIELD_GET(SUN20I_PWM_CLK_CFG_SRC, clk_cfg) != 0; + val = mul_u64_u64_div_u64(state->period, + (use_bus_clk ? bus_rate : hosc_rate), + NSEC_PER_SEC); + + div_m = FIELD_GET(SUN20I_PWM_CLK_CFG_DIV_M, clk_cfg); + } else { + /* check period and select clock source */ + use_bus_clk = false; + val = mul_u64_u64_div_u64(state->period, hosc_rate, NSEC_PER_SEC); + if (val <= 1) { + use_bus_clk = true; + val = mul_u64_u64_div_u64(state->period, bus_rate, NSEC_PER_SEC); + if (val <= 1) { + ret = -EINVAL; + goto unlock_mutex; + } + } + div_m = fls(DIV_ROUND_DOWN_ULL(val, SUN20I_PWM_MAGIC)); + if (div_m > SUN20I_PWM_CLK_DIV_M_MAX) { + ret = -EINVAL; + goto unlock_mutex; + } + + /* set up the CLK_DIV_M and clock CLK_SRC */ + clk_cfg = FIELD_PREP(SUN20I_PWM_CLK_CFG_DIV_M, div_m); + clk_cfg |= FIELD_PREP(SUN20I_PWM_CLK_CFG_SRC, use_bus_clk); + + sun20i_pwm_writel(sun20i_chip, clk_cfg, SUN20I_PWM_CLK_CFG(pwm->hwpwm)); + } + + /* calculate prescale_k, PWM entire cycle */ + ent_cycle = val >> div_m; + prescale_k = DIV_ROUND_DOWN_ULL(ent_cycle, 65537); + if (prescale_k > SUN20I_PWM_CTL_PRESCAL_K_MAX) + prescale_k = SUN20I_PWM_CTL_PRESCAL_K_MAX; + + do_div(ent_cycle, prescale_k + 1); + + /* for N cycles, PPRx.PWM_ENTIRE_CYCLE = (N-1) */ + reg_period = FIELD_PREP(SUN20I_PWM_PERIOD_ENTIRE_CYCLE, ent_cycle - 1); + + /* set duty cycle */ + val = mul_u64_u64_div_u64(state->duty_cycle, + (use_bus_clk ? bus_rate : hosc_rate), + NSEC_PER_SEC); + act_cycle = val >> div_m; + do_div(act_cycle, prescale_k + 1); + + /* + * The formula of the output period and the duty-cycle for PWM are as follows. + * T period = (PWM01_CLK / PWM0_PRESCALE_K)^-1 * (PPR0.PWM_ENTIRE_CYCLE + 1) + * T high-level = (PWM01_CLK / PWM0_PRESCALE_K)^-1 * PPR0.PWM_ACT_CYCLE + * Duty-cycle = T high-level / T period + */ + reg_period |= FIELD_PREP(SUN20I_PWM_PERIOD_ACT_CYCLE, act_cycle); + sun20i_pwm_writel(sun20i_chip, reg_period, SUN20I_PWM_PERIOD(pwm->hwpwm)); + + ctl = FIELD_PREP(SUN20I_PWM_CTL_PRESCAL_K, prescale_k); + if (state->polarity == PWM_POLARITY_NORMAL) + ctl |= SUN20I_PWM_CTL_ACT_STA; + + sun20i_pwm_writel(sun20i_chip, ctl, SUN20I_PWM_CTL(pwm->hwpwm)); + } + + if (state->enabled != pwm->state.enabled && state->enabled) { + clk_gate &= ~SUN20I_PWM_CLK_GATE_BYPASS(pwm->hwpwm); + clk_gate |= SUN20I_PWM_CLK_GATE_GATING(pwm->hwpwm); + pwm_en |= SUN20I_PWM_ENABLE_EN(pwm->hwpwm); + sun20i_pwm_writel(sun20i_chip, pwm_en, SUN20I_PWM_ENABLE); + sun20i_pwm_writel(sun20i_chip, clk_gate, SUN20I_PWM_CLK_GATE); + } + +unlock_mutex: + mutex_unlock(&sun20i_chip->mutex); + + return ret; +} + +static const struct pwm_ops sun20i_pwm_ops = { + .get_state = sun20i_pwm_get_state, + .apply = sun20i_pwm_apply, + .owner = THIS_MODULE, +}; + +static const struct of_device_id sun20i_pwm_dt_ids[] = { + { .compatible = "allwinner,sun20i-d1-pwm" }, + { }, +}; +MODULE_DEVICE_TABLE(of, sun20i_pwm_dt_ids); + +static int sun20i_pwm_probe(struct platform_device *pdev) +{ + struct sun20i_pwm_chip *sun20i_chip; + int ret; + + sun20i_chip = devm_kzalloc(&pdev->dev, sizeof(*sun20i_chip), GFP_KERNEL); + if (!sun20i_chip) + return -ENOMEM; + + sun20i_chip->base = devm_platform_ioremap_resource(pdev, 0); + if (IS_ERR(sun20i_chip->base)) + return PTR_ERR(sun20i_chip->base); + + sun20i_chip->clk_bus = devm_clk_get_enabled(&pdev->dev, "bus"); + if (IS_ERR(sun20i_chip->clk_bus)) + return dev_err_probe(&pdev->dev, PTR_ERR(sun20i_chip->clk_bus), + "failed to get bus clock\n"); + + sun20i_chip->clk_hosc = devm_clk_get_enabled(&pdev->dev, "hosc"); + if (IS_ERR(sun20i_chip->clk_hosc)) + return dev_err_probe(&pdev->dev, PTR_ERR(sun20i_chip->clk_hosc), + "failed to get hosc clock\n"); + + sun20i_chip->clk_apb0 = devm_clk_get_enabled(&pdev->dev, "apb0"); + if (IS_ERR(sun20i_chip->clk_apb0)) + return dev_err_probe(&pdev->dev, PTR_ERR(sun20i_chip->clk_apb0), + "failed to get apb0 clock\n"); + + sun20i_chip->rst = devm_reset_control_get_exclusive(&pdev->dev, NULL); + if (IS_ERR(sun20i_chip->rst)) + return dev_err_probe(&pdev->dev, PTR_ERR(sun20i_chip->rst), + "failed to get bus reset\n"); + + ret = of_property_read_u32(pdev->dev.of_node, "allwinner,pwm-channels", + &sun20i_chip->chip.npwm); + if (ret) + sun20i_chip->chip.npwm = 8; + + if (sun20i_chip->chip.npwm > 16) + sun20i_chip->chip.npwm = 16; + + /* Deassert reset */ + ret = reset_control_deassert(sun20i_chip->rst); + if (ret) + return dev_err_probe(&pdev->dev, ret, "failed to deassert reset\n"); + + sun20i_chip->chip.dev = &pdev->dev; + sun20i_chip->chip.ops = &sun20i_pwm_ops; + + mutex_init(&sun20i_chip->mutex); + + ret = pwmchip_add(&sun20i_chip->chip); + if (ret < 0) { + reset_control_assert(sun20i_chip->rst); + return dev_err_probe(&pdev->dev, ret, "failed to add PWM chip\n"); + } + + platform_set_drvdata(pdev, sun20i_chip); + + return 0; +} + +static void sun20i_pwm_remove(struct platform_device *pdev) +{ + struct sun20i_pwm_chip *sun20i_chip = platform_get_drvdata(pdev); + + pwmchip_remove(&sun20i_chip->chip); 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Wed, 24 Jan 2024 23:21:54 -0800 (PST) From: Aleksandr Shubin To: linux-kernel@vger.kernel.org Subject: [PATCH v7 3/3] riscv: dts: allwinner: d1: Add pwm node Date: Thu, 25 Jan 2024 10:19:43 +0300 Message-Id: <20240125072032.1151383-4-privatesub2@gmail.com> X-Mailer: git-send-email 2.25.1 In-Reply-To: <20240125072032.1151383-1-privatesub2@gmail.com> References: <20240125072032.1151383-1-privatesub2@gmail.com> MIME-Version: 1.0 X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20240124_232209_399764_C7EA6851 X-CRM114-Status: GOOD ( 11.17 ) X-BeenThere: linux-riscv@lists.infradead.org X-Mailman-Version: 2.1.34 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: devicetree@vger.kernel.org, John Watts , Krzysztof Kozlowski , linux-riscv@lists.infradead.org, Samuel Holland , Albert Ou , Jernej Skrabec , Chen-Yu Tsai , =?utf-8?q?Uwe_Kleine-K=C3=B6nig?= , linux-sunxi@lists.linux.dev, linux-pwm@vger.kernel.org, Conor Dooley , Aleksandr Shubin , Rob Herring , Marc Kleine-Budde , Paul Walmsley , Maksim Kiselev , linux-arm-kernel@lists.infradead.org, Cheo Fusi , Palmer Dabbelt , Philipp Zabel Sender: "linux-riscv" Errors-To: linux-riscv-bounces+linux-riscv=archiver.kernel.org@lists.infradead.org D1 and T113s contain a pwm controller with 8 channels. This controller is supported by the sun20i-pwm driver. Add a device tree node for it. Signed-off-by: Aleksandr Shubin --- arch/riscv/boot/dts/allwinner/sunxi-d1s-t113.dtsi | 12 ++++++++++++ 1 file changed, 12 insertions(+) diff --git a/arch/riscv/boot/dts/allwinner/sunxi-d1s-t113.dtsi b/arch/riscv/boot/dts/allwinner/sunxi-d1s-t113.dtsi index 5a9d7f5a75b4..435a1e66aa6a 100644 --- a/arch/riscv/boot/dts/allwinner/sunxi-d1s-t113.dtsi +++ b/arch/riscv/boot/dts/allwinner/sunxi-d1s-t113.dtsi @@ -145,6 +145,18 @@ uart3_pb_pins: uart3-pb-pins { }; }; + pwm: pwm@2000c00 { + compatible = "allwinner,sun20i-d1-pwm"; + reg = <0x02000c00 0x400>; + clocks = <&ccu CLK_BUS_PWM>, + <&dcxo>, + <&ccu CLK_APB0>; + clock-names = "bus", "hosc", "apb0"; + resets = <&ccu RST_BUS_PWM>; + status = "disabled"; + #pwm-cells = <0x3>; + }; + ccu: clock-controller@2001000 { compatible = "allwinner,sun20i-d1-ccu"; reg = <0x2001000 0x1000>;