From patchwork Wed Sep 11 19:50:05 2024 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Lorenzo Bianconi X-Patchwork-Id: 827526 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-1.web.codeaurora.org [10.30.226.201]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 77F4A17DFFC; Wed, 11 Sep 2024 19:51:19 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=10.30.226.201 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1726084279; cv=none; b=MYE/hUFFvj5f1GkDkTXcZlYaQsIAo3LezCnlHY/ekh3cpxMny7IKZnfR40DbK+h3ZMN/yP0s/5KapD17r0YfFho6eERQfliDc0QTMLW2JKOG53FSkZ9izYq4Kv+z957EgzsmkE8DymDPXdrUByAupgDZqfkZPdEY9inT+fFXhyY= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1726084279; c=relaxed/simple; bh=4I4G8bZBqDJ2HsWRC0P9SVr2iP8mE3fCk30nlYLxnKc=; h=From:Date:Subject:MIME-Version:Content-Type:Message-Id:References: In-Reply-To:To:Cc; b=rD6uZV44LcMAgu/p5cFtkkLbNMVvvvC7juo5NVSvXaUb4zjsJjLH/E+dRn1eOTZKfasGxSQjRuGDMa2FiDViJUKM+3ukrtHBD+s7yj34QWgp2bhHvq/ECdt+0YmQBBdb26S3JkDh8ZaxUm8E7OrWI9WxmqUVCxxe1Y92b8yucBQ= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=JCf5aaxs; arc=none smtp.client-ip=10.30.226.201 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b="JCf5aaxs" Received: by smtp.kernel.org (Postfix) with ESMTPSA id B42B2C4CEC0; Wed, 11 Sep 2024 19:51:18 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1726084279; bh=4I4G8bZBqDJ2HsWRC0P9SVr2iP8mE3fCk30nlYLxnKc=; h=From:Date:Subject:References:In-Reply-To:To:Cc:From; b=JCf5aaxsRemFEDlhKvBg69NH+at3ESY2n23wLNZ8/LT7posxFDm8zcMBMZlM3FzyY tIz91yaFWZH8gP8sEXAMv70y6sl8ty7OQaeUSQF3wXfIgzYDrf9tRxe0fMawOQ8kNS WcKQhYZWaEQdxchrfshuxI2Jn0EfDTXZyl9xGD7WFrfkaZSnfHsT5Gn8sNdfv2nAcU 3ev3OhrR739ZdkGGLCK7JpiieesZta6Je+9Z4oTjsPGuQY1VVcVq3fYajkp9K4gBh1 AvUmlpueXxw8I7IqAvDXU4UnS1shcKMhwudTWtneM8jOCpEtRoMqHStKT0PH/02Mws 5d/bFBeQCdiOQ== From: Lorenzo Bianconi Date: Wed, 11 Sep 2024 21:50:05 +0200 Subject: [PATCH v4 5/5] pwm: airoha: Add support for EN7581 SoC Precedence: bulk X-Mailing-List: linux-gpio@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Message-Id: <20240911-en7581-pinctrl-v4-5-60ac93d760bb@kernel.org> References: <20240911-en7581-pinctrl-v4-0-60ac93d760bb@kernel.org> In-Reply-To: <20240911-en7581-pinctrl-v4-0-60ac93d760bb@kernel.org> To: Lorenzo Bianconi , Linus Walleij , Rob Herring , Krzysztof Kozlowski , Conor Dooley , Sean Wang , Matthias Brugger , AngeloGioacchino Del Regno , Lee Jones , =?utf-8?q?Uwe_Kleine-K=C3=B6nig?= Cc: linux-mediatek@lists.infradead.org, linux-gpio@vger.kernel.org, devicetree@vger.kernel.org, linux-arm-kernel@lists.infradead.org, upstream@airoha.com, benjamin.larsson@genexis.eu, ansuelsmth@gmail.com, linux-pwm@vger.kernel.org X-Mailer: b4 0.14.1 From: Benjamin Larsson Introduce driver for PWM module available on EN7581 SoC. Signed-off-by: Benjamin Larsson Co-developed-by: Lorenzo Bianconi Signed-off-by: Lorenzo Bianconi --- drivers/pwm/Kconfig | 10 ++ drivers/pwm/Makefile | 1 + drivers/pwm/pwm-airoha.c | 414 +++++++++++++++++++++++++++++++++++++++++++++++ 3 files changed, 425 insertions(+) diff --git a/drivers/pwm/Kconfig b/drivers/pwm/Kconfig index 3e53838990f5..0a78bda0707d 100644 --- a/drivers/pwm/Kconfig +++ b/drivers/pwm/Kconfig @@ -47,6 +47,16 @@ config PWM_AB8500 To compile this driver as a module, choose M here: the module will be called pwm-ab8500. +config PWM_AIROHA + tristate "Airoha PWM support" + depends on ARCH_AIROHA || COMPILE_TEST + depends on OF + help + Generic PWM framework driver for Airoha SoC. + + To compile this driver as a module, choose M here: the module + will be called pwm-airoha. + config PWM_APPLE tristate "Apple SoC PWM support" depends on ARCH_APPLE || COMPILE_TEST diff --git a/drivers/pwm/Makefile b/drivers/pwm/Makefile index 0be4f3e6dd43..7ee61822d88d 100644 --- a/drivers/pwm/Makefile +++ b/drivers/pwm/Makefile @@ -1,6 +1,7 @@ # SPDX-License-Identifier: GPL-2.0 obj-$(CONFIG_PWM) += core.o obj-$(CONFIG_PWM_AB8500) += pwm-ab8500.o +obj-$(CONFIG_PWM_AIROHA) += pwm-airoha.o obj-$(CONFIG_PWM_APPLE) += pwm-apple.o obj-$(CONFIG_PWM_ATMEL) += pwm-atmel.o obj-$(CONFIG_PWM_ATMEL_HLCDC_PWM) += pwm-atmel-hlcdc.o diff --git a/drivers/pwm/pwm-airoha.c b/drivers/pwm/pwm-airoha.c new file mode 100644 index 000000000000..bab2e15e06e7 --- /dev/null +++ b/drivers/pwm/pwm-airoha.c @@ -0,0 +1,414 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * Copyright 2022 Markus Gothe + * + * Limitations: + * - No disable bit, so a disabled PWM is simulated by setting duty_cycle to 0 + * - Only 8 concurrent waveform generators are available for 8 combinations of + * duty_cycle and period. Waveform generators are shared between 16 GPIO + * pins and 17 SIPO GPIO pins. + * - Supports only normal polarity. + * - On configuration the currently running period is completed. + */ + +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include + +#define REG_SGPIO_LED_DATA 0x0024 +#define SGPIO_LED_DATA_SHIFT_FLAG BIT(31) +#define SGPIO_LED_DATA_DATA GENMASK(16, 0) + +#define REG_SGPIO_CLK_DIVR 0x0028 +#define REG_SGPIO_CLK_DLY 0x002c + +#define REG_SIPO_FLASH_MODE_CFG 0x0030 +#define SERIAL_GPIO_FLASH_MODE BIT(1) +#define SERIAL_GPIO_MODE BIT(0) + +#define REG_GPIO_FLASH_PRD_SET(_n) (0x003c + ((_n) << 2)) +#define GPIO_FLASH_PRD_MASK(_n) GENMASK(15 + ((_n) << 4), ((_n) << 4)) + +#define REG_GPIO_FLASH_MAP(_n) (0x004c + ((_n) << 2)) +#define GPIO_FLASH_SETID_MASK(_n) GENMASK(2 + ((_n) << 2), ((_n) << 2)) +#define GPIO_FLASH_EN(_n) BIT(3 + ((_n) << 2)) + +#define REG_SIPO_FLASH_MAP(_n) (0x0054 + ((_n) << 2)) + +#define REG_CYCLE_CFG_VALUE(_n) (0x0098 + ((_n) << 2)) +#define WAVE_GEN_CYCLE_MASK(_n) GENMASK(7 + ((_n) << 3), ((_n) << 3)) + +struct airoha_pwm { + void __iomem *base; + + struct device_node *np; + u64 initialized; + + struct { + /* Bitmask of PWM channels using this bucket */ + u64 used; + u64 period_ns; + u64 duty_ns; + } bucket[8]; +}; + +/* + * The first 16 GPIO pins, GPIO0-GPIO15, are mapped into 16 PWM channels, 0-15. + * The SIPO GPIO pins are 17 pins which are mapped into 17 PWM channels, 16-32. + * However, we've only got 8 concurrent waveform generators and can therefore + * only use up to 8 different combinations of duty cycle and period at a time. + */ +#define PWM_NUM_GPIO 16 +#define PWM_NUM_SIPO 17 + +/* The PWM hardware supports periods between 4 ms and 1 s */ +#define PERIOD_MIN_NS (4 * NSEC_PER_MSEC) +#define PERIOD_MAX_NS (1 * NSEC_PER_SEC) +/* It is represented internally as 1/250 s between 1 and 250 */ +#define PERIOD_MIN 1 +#define PERIOD_MAX 250 +/* Duty cycle is relative with 255 corresponding to 100% */ +#define DUTY_FULL 255 + +static u32 airoha_pwm_rmw(struct airoha_pwm *pc, u32 addr, u32 mask, u32 val) +{ + val |= (readl(pc->base + addr) & ~mask); + writel(val, pc->base + addr); + + return val; +} + +#define airoha_pwm_set_bits(pc, addr, val) \ + airoha_pwm_rmw((pc), (addr), (val), (val)) + +#define airoha_pwm_clear_bit(pc, addr, mask) \ + airoha_pwm_rmw(pc, addr, mask, 0) + +static int airoha_pwm_get_generator(struct airoha_pwm *pc, u64 duty_ns, + u64 period_ns) +{ + int i; + + for (i = 0; i < ARRAY_SIZE(pc->bucket); i++) { + if (!pc->bucket[i].used) + continue; + + if (duty_ns == pc->bucket[i].duty_ns && + period_ns == pc->bucket[i].period_ns) + return i; + + /* + * Unlike duty cycle zero, which can be handled by + * disabling PWM, a generator is needed for full duty + * cycle but it can be reused regardless of period + */ + if (duty_ns == DUTY_FULL && pc->bucket[i].duty_ns == DUTY_FULL) + return i; + } + + return -1; +} + +static void airoha_pwm_release_bucket_config(struct airoha_pwm *pc, + unsigned int hwpwm) +{ + int i; + + for (i = 0; i < ARRAY_SIZE(pc->bucket); i++) + pc->bucket[i].used &= ~BIT_ULL(hwpwm); +} + +static int airoha_pwm_consume_generator(struct airoha_pwm *pc, + u64 duty_ns, u64 period_ns, + unsigned int hwpwm) +{ + int id = airoha_pwm_get_generator(pc, duty_ns, period_ns); + + if (id < 0) { + int i; + + /* find an unused waveform generator */ + for (i = 0; i < ARRAY_SIZE(pc->bucket); i++) { + if (!(pc->bucket[i].used & ~BIT_ULL(hwpwm))) { + id = i; + break; + } + } + } + + if (id >= 0) { + airoha_pwm_release_bucket_config(pc, hwpwm); + pc->bucket[id].used |= BIT_ULL(hwpwm); + pc->bucket[id].period_ns = period_ns; + pc->bucket[id].duty_ns = duty_ns; + } + + return id; +} + +static int airoha_pwm_sipo_init(struct airoha_pwm *pc) +{ + u32 clk_divr_val = 3, sipo_clock_delay = 1; + u32 val, sipo_clock_divisor = 32; + + if (!(pc->initialized >> PWM_NUM_GPIO)) + return 0; + + /* Select the right shift register chip */ + if (of_property_read_bool(pc->np, "hc74595")) + airoha_pwm_set_bits(pc, REG_SIPO_FLASH_MODE_CFG, + SERIAL_GPIO_MODE); + else + airoha_pwm_clear_bit(pc, REG_SIPO_FLASH_MODE_CFG, + SERIAL_GPIO_MODE); + + if (!of_property_read_u32(pc->np, "sipo-clock-divisor", + &sipo_clock_divisor)) { + switch (sipo_clock_divisor) { + case 4: + clk_divr_val = 0; + break; + case 8: + clk_divr_val = 1; + break; + case 16: + clk_divr_val = 2; + break; + case 32: + clk_divr_val = 3; + break; + default: + return -EINVAL; + } + } + /* Configure shift register timings */ + writel(clk_divr_val, pc->base + REG_SGPIO_CLK_DIVR); + + of_property_read_u32(pc->np, "sipo-clock-delay", &sipo_clock_delay); + if (sipo_clock_delay < 1 || sipo_clock_delay > sipo_clock_divisor / 2) + return -EINVAL; + + /* + * The actual delay is sclkdly + 1 so subtract 1 from + * sipo-clock-delay to calculate the register value + */ + sipo_clock_delay--; + writel(sipo_clock_delay, pc->base + REG_SGPIO_CLK_DLY); + + /* + * It it necessary to after muxing explicitly shift out all + * zeroes to initialize the shift register before enabling PWM + * mode because in PWM mode SIPO will not start shifting until + * it needs to output a non-zero value (bit 31 of led_data + * indicates shifting in progress and it must return to zero + * before led_data can be written or PWM mode can be set) + */ + if (readl_poll_timeout(pc->base + REG_SGPIO_LED_DATA, val, + !(val & SGPIO_LED_DATA_SHIFT_FLAG), 10, + 200 * USEC_PER_MSEC)) + return -ETIMEDOUT; + + airoha_pwm_clear_bit(pc, REG_SGPIO_LED_DATA, SGPIO_LED_DATA_DATA); + if (readl_poll_timeout(pc->base + REG_SGPIO_LED_DATA, val, + !(val & SGPIO_LED_DATA_SHIFT_FLAG), 10, + 200 * USEC_PER_MSEC)) + return -ETIMEDOUT; + + /* Set SIPO in PWM mode */ + airoha_pwm_set_bits(pc, REG_SIPO_FLASH_MODE_CFG, + SERIAL_GPIO_FLASH_MODE); + + return 0; +} + +static void airoha_pwm_calc_bucket_config(struct airoha_pwm *pc, int index, + u64 duty_ns, u64 period_ns) +{ + u32 period, duty, mask, val; + u64 tmp; + + tmp = duty_ns * DUTY_FULL; + duty = clamp_val(div64_u64(tmp, period_ns), 0, DUTY_FULL); + tmp = period_ns * 25; + period = clamp_val(div64_u64(tmp, 100000000), PERIOD_MIN, PERIOD_MAX); + + /* Configure frequency divisor */ + mask = WAVE_GEN_CYCLE_MASK(index % 4); + val = (period << __ffs(mask)) & mask; + airoha_pwm_rmw(pc, REG_CYCLE_CFG_VALUE(index / 4), mask, val); + + /* Configure duty cycle */ + duty = ((DUTY_FULL - duty) << 8) | duty; + mask = GPIO_FLASH_PRD_MASK(index % 2); + val = (duty << __ffs(mask)) & mask; + airoha_pwm_rmw(pc, REG_GPIO_FLASH_PRD_SET(index / 2), mask, val); +} + +static void airoha_pwm_config_flash_map(struct airoha_pwm *pc, + unsigned int hwpwm, int index) +{ + u32 addr, mask, val; + + if (hwpwm < PWM_NUM_GPIO) { + addr = REG_GPIO_FLASH_MAP(hwpwm / 8); + } else { + addr = REG_SIPO_FLASH_MAP(hwpwm / 8); + hwpwm -= PWM_NUM_GPIO; + } + + if (index < 0) { + /* + * Change of waveform takes effect immediately but + * disabling has some delay so to prevent glitching + * only the enable bit is touched when disabling + */ + airoha_pwm_clear_bit(pc, addr, GPIO_FLASH_EN(hwpwm % 8)); + return; + } + + mask = GPIO_FLASH_SETID_MASK(hwpwm % 8); + val = ((index & 7) << __ffs(mask)) & mask; + airoha_pwm_rmw(pc, addr, mask, val); + airoha_pwm_set_bits(pc, addr, GPIO_FLASH_EN(hwpwm % 8)); +} + +static int airoha_pwm_config(struct airoha_pwm *pc, struct pwm_device *pwm, + u64 duty_ns, u64 period_ns) +{ + int index = -1; + + index = airoha_pwm_consume_generator(pc, duty_ns, period_ns, + pwm->hwpwm); + if (index < 0) + return -EBUSY; + + if (!(pc->initialized & BIT_ULL(pwm->hwpwm)) && + pwm->hwpwm >= PWM_NUM_GPIO) + airoha_pwm_sipo_init(pc); + + if (index >= 0) { + airoha_pwm_calc_bucket_config(pc, index, duty_ns, period_ns); + airoha_pwm_config_flash_map(pc, pwm->hwpwm, index); + } else { + airoha_pwm_config_flash_map(pc, pwm->hwpwm, index); + airoha_pwm_release_bucket_config(pc, pwm->hwpwm); + } + + pc->initialized |= BIT_ULL(pwm->hwpwm); + + return 0; +} + +static void airoha_pwm_disable(struct pwm_chip *chip, struct pwm_device *pwm) +{ + struct airoha_pwm *pc = pwmchip_get_drvdata(chip); + + /* Disable PWM and release the waveform */ + airoha_pwm_config_flash_map(pc, pwm->hwpwm, -1); + airoha_pwm_release_bucket_config(pc, pwm->hwpwm); + + pc->initialized &= ~BIT_ULL(pwm->hwpwm); + if (!(pc->initialized >> PWM_NUM_GPIO)) + airoha_pwm_clear_bit(pc, REG_SIPO_FLASH_MODE_CFG, + SERIAL_GPIO_FLASH_MODE); +} + +static int airoha_pwm_apply(struct pwm_chip *chip, struct pwm_device *pwm, + const struct pwm_state *state) +{ + struct airoha_pwm *pc = pwmchip_get_drvdata(chip); + u64 duty = state->enabled ? state->duty_cycle : 0; + u64 period = state->period; + + /* Only normal polarity is supported */ + if (state->polarity == PWM_POLARITY_INVERSED) + return -EINVAL; + + if (!state->enabled) { + airoha_pwm_disable(chip, pwm); + return 0; + } + + if (period < PERIOD_MIN_NS) + return -EINVAL; + + if (period > PERIOD_MAX_NS) + period = PERIOD_MAX_NS; + + return airoha_pwm_config(pc, pwm, duty, period); +} + +static int airoha_pwm_get_state(struct pwm_chip *chip, struct pwm_device *pwm, + struct pwm_state *state) +{ + struct airoha_pwm *pc = pwmchip_get_drvdata(chip); + int i; + + /* find hwpwm in waveform generator bucket */ + for (i = 0; i < ARRAY_SIZE(pc->bucket); i++) { + if (pc->bucket[i].used & BIT_ULL(pwm->hwpwm)) { + state->enabled = pc->initialized & BIT_ULL(pwm->hwpwm); + state->polarity = PWM_POLARITY_NORMAL; + state->period = pc->bucket[i].period_ns; + state->duty_cycle = pc->bucket[i].duty_ns; + break; + } + } + + if (i == ARRAY_SIZE(pc->bucket)) + state->enabled = false; + + return 0; +} + +static const struct pwm_ops airoha_pwm_ops = { + .get_state = airoha_pwm_get_state, + .apply = airoha_pwm_apply, +}; + +static int airoha_pwm_probe(struct platform_device *pdev) +{ + struct device *dev = &pdev->dev; + struct airoha_mfd *mfd; + struct airoha_pwm *pc; + struct pwm_chip *chip; + + /* Assign parent MFD of_node to dev */ + device_set_of_node_from_dev(dev, dev->parent); + mfd = dev_get_drvdata(dev->parent); + + chip = devm_pwmchip_alloc(dev, PWM_NUM_GPIO + PWM_NUM_SIPO, + sizeof(*pc)); + if (IS_ERR(chip)) + return PTR_ERR(chip); + + pc = pwmchip_get_drvdata(chip); + pc->np = dev->of_node; + pc->base = mfd->base; + chip->ops = &airoha_pwm_ops; + + return devm_pwmchip_add(&pdev->dev, chip); +} + +static struct platform_driver airoha_pwm_driver = { + .driver = { + .name = "pwm-airoha", + }, + .probe = airoha_pwm_probe, +}; +module_platform_driver(airoha_pwm_driver); + +MODULE_AUTHOR("Lorenzo Bianconi "); +MODULE_AUTHOR("Markus Gothe "); +MODULE_AUTHOR("Benjamin Larsson "); +MODULE_DESCRIPTION("Airoha EN7581 PWM driver"); +MODULE_LICENSE("GPL");