[U-Boot] [PATCH 07/37] pwm: rockchip: Add a PWM driver for Rockchip SoCs
Simon Glass
sjg at chromium.org
Thu Jan 14 16:57:50 CET 2016
Add a simple driver which implements the standard PWM uclass interface.
Signed-off-by: Simon Glass <sjg at chromium.org>
---
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 at 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),
+};
--
2.6.0.rc2.230.g3dd15c0
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