Add a simple driver which implements the standard PWM uclass interface.
Signed-off-by: Simon Glass sjg@chromium.org ---
Changes in v2: None
arch/arm/include/asm/arch-rockchip/pwm.h | 41 ++++++++++++ drivers/pwm/Kconfig | 9 +++ drivers/pwm/Makefile | 1 + drivers/pwm/rk_pwm.c | 103 +++++++++++++++++++++++++++++++ 4 files changed, 154 insertions(+) create mode 100644 arch/arm/include/asm/arch-rockchip/pwm.h create mode 100644 drivers/pwm/rk_pwm.c
diff --git a/arch/arm/include/asm/arch-rockchip/pwm.h b/arch/arm/include/asm/arch-rockchip/pwm.h new file mode 100644 index 0000000..08ff945 --- /dev/null +++ b/arch/arm/include/asm/arch-rockchip/pwm.h @@ -0,0 +1,41 @@ +/* + * (C) Copyright 2016 Google, Inc + * (C) Copyright 2008-2014 Rockchip Electronics + * + * SPDX-License-Identifier: GPL-2.0+ + */ + +#ifndef _ASM_ARCH_PWM_H +#define _ASM_ARCH_PWM_H + +struct rk3288_pwm { + u32 cnt; + u32 period_hpr; + u32 duty_lpr; + u32 ctrl; +}; +check_member(rk3288_pwm, ctrl, 0xc); + +#define RK_PWM_DISABLE (0 << 0) +#define RK_PWM_ENABLE (1 << 0) + +#define PWM_ONE_SHOT (0 << 1) +#define PWM_CONTINUOUS (1 << 1) +#define RK_PWM_CAPTURE (1 << 2) + +#define PWM_DUTY_POSTIVE (1 << 3) +#define PWM_DUTY_NEGATIVE (0 << 3) + +#define PWM_INACTIVE_POSTIVE (1 << 4) +#define PWM_INACTIVE_NEGATIVE (0 << 4) + +#define PWM_OUTPUT_LEFT (0 << 5) +#define PWM_OUTPUT_CENTER (1 << 5) + +#define PWM_LP_ENABLE (1 << 8) +#define PWM_LP_DISABLE (0 << 8) + +#define PWM_SEL_SCALE_CLK (1 << 9) +#define PWM_SEL_SRC_CLK (0 << 9) + +#endif diff --git a/drivers/pwm/Kconfig b/drivers/pwm/Kconfig index bd47159..cd8f357 100644 --- a/drivers/pwm/Kconfig +++ b/drivers/pwm/Kconfig @@ -8,3 +8,12 @@ config DM_PWM spends in the 'high' state, the higher the voltage. The PWM's frequency/period can be controlled along with the proportion of that time that the signal is high. + +config PWM_ROCKCHIP + bool "Enable support for the Rockchip PWM" + depends on DM_PWM + help + This PWM is found on RK3288 and other Rockchip SoCs. It supports a + programmable period and duty cycle. A 32-bit counter is used. + Various options provided in the hardware (such as capture mode and + continuous/single-shot) are not supported by the driver. diff --git a/drivers/pwm/Makefile b/drivers/pwm/Makefile index d1b15e5..b6d8c16 100644 --- a/drivers/pwm/Makefile +++ b/drivers/pwm/Makefile @@ -11,4 +11,5 @@ #ccflags-y += -DDEBUG
obj-$(CONFIG_DM_PWM) += pwm-uclass.o +obj-$(CONFIG_PWM_ROCKCHIP) += rk_pwm.o obj-$(CONFIG_PWM_IMX) += pwm-imx.o pwm-imx-util.o diff --git a/drivers/pwm/rk_pwm.c b/drivers/pwm/rk_pwm.c new file mode 100644 index 0000000..2d289a4 --- /dev/null +++ b/drivers/pwm/rk_pwm.c @@ -0,0 +1,103 @@ +/* + * Copyright (c) 2016 Google, Inc + * Written by Simon Glass sjg@chromium.org + * + * SPDX-License-Identifier: GPL-2.0+ + */ + +#include <common.h> +#include <div64.h> +#include <dm.h> +#include <pwm.h> +#include <regmap.h> +#include <syscon.h> +#include <asm/io.h> +#include <asm/arch/clock.h> +#include <asm/arch/cru_rk3288.h> +#include <asm/arch/grf_rk3288.h> +#include <asm/arch/pwm.h> +#include <power/regulator.h> + +DECLARE_GLOBAL_DATA_PTR; + +struct rk_pwm_priv { + struct rk3288_pwm *regs; + struct rk3288_grf *grf; +}; + +static int rk_pwm_set_config(struct udevice *dev, uint channel, uint period_ns, + uint duty_ns) +{ + struct rk_pwm_priv *priv = dev_get_priv(dev); + struct rk3288_pwm *regs = priv->regs; + unsigned long period, duty; + + debug("%s: period_ns=%u, duty_ns=%u\n", __func__, period_ns, duty_ns); + writel(PWM_SEL_SRC_CLK | PWM_OUTPUT_LEFT | PWM_LP_DISABLE | + PWM_CONTINUOUS | PWM_DUTY_POSTIVE | PWM_INACTIVE_POSTIVE | + RK_PWM_DISABLE, + ®s->ctrl); + + period = lldiv((uint64_t)(PD_BUS_PCLK_HZ / 1000) * period_ns, 1000000); + duty = lldiv((uint64_t)(PD_BUS_PCLK_HZ / 1000) * duty_ns, 1000000); + + writel(period, ®s->period_hpr); + writel(duty, ®s->duty_lpr); + debug("%s: period=%lu, duty=%lu\n", __func__, period, duty); + + return 0; +} + +static int rk_pwm_set_enable(struct udevice *dev, uint channel, bool enable) +{ + struct rk_pwm_priv *priv = dev_get_priv(dev); + struct rk3288_pwm *regs = priv->regs; + + debug("%s: Enable '%s'\n", __func__, dev->name); + clrsetbits_le32(®s->ctrl, RK_PWM_ENABLE, enable ? RK_PWM_ENABLE : 0); + + return 0; +} + +static int rk_pwm_ofdata_to_platdata(struct udevice *dev) +{ + struct rk_pwm_priv *priv = dev_get_priv(dev); + struct regmap *map; + + priv->regs = (struct rk3288_pwm *)dev_get_addr(dev); + map = syscon_get_regmap_by_driver_data(ROCKCHIP_SYSCON_GRF); + if (IS_ERR(map)) + return PTR_ERR(map); + priv->grf = regmap_get_range(map, 0); + + return 0; +} + +static int rk_pwm_probe(struct udevice *dev) +{ + struct rk_pwm_priv *priv = dev_get_priv(dev); + + rk_setreg(&priv->grf->soc_con2, 1 << 0); + + return 0; +} + +static const struct pwm_ops rk_pwm_ops = { + .set_config = rk_pwm_set_config, + .set_enable = rk_pwm_set_enable, +}; + +static const struct udevice_id rk_pwm_ids[] = { + { .compatible = "rockchip,rk3288-pwm" }, + { } +}; + +U_BOOT_DRIVER(rk_pwm) = { + .name = "rk_pwm", + .id = UCLASS_PWM, + .of_match = rk_pwm_ids, + .ops = &rk_pwm_ops, + .ofdata_to_platdata = rk_pwm_ofdata_to_platdata, + .probe = rk_pwm_probe, + .priv_auto_alloc_size = sizeof(struct rk_pwm_priv), +};