Commit 0e23fd81 authored by Simon Glass's avatar Simon Glass
Browse files

pwm: rockchip: Add a PWM driver for Rockchip SoCs



Add a simple driver which implements the standard PWM uclass interface.
Signed-off-by: default avatarSimon Glass <sjg@chromium.org>
parent fc760cb8
/*
* (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
......@@ -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.
......@@ -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
/*
* 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,
&regs->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, &regs->period_hpr);
writel(duty, &regs->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(&regs->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),
};
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