The ADC can support some channels signal-ended some bits Successive Approximation Register (SAR) A/D Converter, like 6-channel and 10-bit. It converts the analog input signal into some bits binary digital codes.
Signed-off-by: David Wu david.wu@rock-chips.com Acked-by: Philipp Tomsich philipp.tomsich@theobroma-systems.com Reviewed-by: Philipp Tomsich philipp.tomsich@theobroma-systems.com ---
Changes in v2: - Order the the include file. - Use structures for I/O access. - Use dev_read_add.
drivers/adc/Kconfig | 9 +++ drivers/adc/Makefile | 1 + drivers/adc/rockchip-saradc.c | 183 ++++++++++++++++++++++++++++++++++++++++++ 3 files changed, 193 insertions(+) create mode 100644 drivers/adc/rockchip-saradc.c
diff --git a/drivers/adc/Kconfig b/drivers/adc/Kconfig index e5335f7..8094420 100644 --- a/drivers/adc/Kconfig +++ b/drivers/adc/Kconfig @@ -28,3 +28,12 @@ config ADC_SANDBOX - 4 analog input channels - 16-bit resolution - single and multi-channel conversion mode + +config SARADC_ROCKCHIP + bool "Enable Rockchip SARADC driver" + help + This enables driver for Rockchip SARADC. + It provides: + - 2~6 analog input channels + - 1O or 12 bits resolution + - Up to 1MSPS of sample rate diff --git a/drivers/adc/Makefile b/drivers/adc/Makefile index cebf26d..4b5aa69 100644 --- a/drivers/adc/Makefile +++ b/drivers/adc/Makefile @@ -8,3 +8,4 @@ obj-$(CONFIG_ADC) += adc-uclass.o obj-$(CONFIG_ADC_EXYNOS) += exynos-adc.o obj-$(CONFIG_ADC_SANDBOX) += sandbox.o +obj-$(CONFIG_SARADC_ROCKCHIP) += rockchip-saradc.o diff --git a/drivers/adc/rockchip-saradc.c b/drivers/adc/rockchip-saradc.c new file mode 100644 index 0000000..0e6271d --- /dev/null +++ b/drivers/adc/rockchip-saradc.c @@ -0,0 +1,183 @@ +/* + * (C) Copyright 2017, Fuzhou Rockchip Electronics Co., Ltd + * + * SPDX-License-Identifier: GPL-2.0+ + * + * Rockchip SARADC driver for U-Boot + */ + +#include <common.h> +#include <adc.h> +#include <clk.h> +#include <dm.h> +#include <errno.h> +#include <asm/io.h> + +#define SARADC_CTRL_CHN_MASK GENMASK(2, 0) +#define SARADC_CTRL_POWER_CTRL BIT(3) +#define SARADC_CTRL_IRQ_ENABLE BIT(5) +#define SARADC_CTRL_IRQ_STATUS BIT(6) + +#define SARADC_TIMEOUT (100 * 1000) + +struct rockchip_saradc_regs { + unsigned int data; + unsigned int stas; + unsigned int ctrl; + unsigned int dly_pu_soc; +}; + +struct rockchip_saradc_data { + int num_bits; + int num_channels; + unsigned long clk_rate; +}; + +struct rockchip_saradc_priv { + struct rockchip_saradc_regs *regs; + int active_channel; + const struct rockchip_saradc_data *data; +}; + +int rockchip_saradc_channel_data(struct udevice *dev, int channel, + unsigned int *data) +{ + struct rockchip_saradc_priv *priv = dev_get_priv(dev); + struct adc_uclass_platdata *uc_pdata = dev_get_uclass_platdata(dev); + + if (channel != priv->active_channel) { + error("Requested channel is not active!"); + return -EINVAL; + } + + if ((readl(&priv->regs->ctrl) & SARADC_CTRL_IRQ_STATUS) != + SARADC_CTRL_IRQ_STATUS) + return -EBUSY; + + /* Read value */ + *data = readl(&priv->regs->data); + *data &= uc_pdata->data_mask; + + /* Power down adc */ + writel(0, &priv->regs->ctrl); + + return 0; +} + +int rockchip_saradc_start_channel(struct udevice *dev, int channel) +{ + struct rockchip_saradc_priv *priv = dev_get_priv(dev); + + if (channel < 0 || channel >= priv->data->num_channels) { + error("Requested channel is invalid!"); + return -EINVAL; + } + + /* 8 clock periods as delay between power up and start cmd */ + writel(8, &priv->regs->dly_pu_soc); + + /* Select the channel to be used and trigger conversion */ + writel(SARADC_CTRL_POWER_CTRL | (channel & SARADC_CTRL_CHN_MASK) | + SARADC_CTRL_IRQ_ENABLE, &priv->regs->ctrl); + + priv->active_channel = channel; + + return 0; +} + +int rockchip_saradc_stop(struct udevice *dev) +{ + struct rockchip_saradc_priv *priv = dev_get_priv(dev); + + /* Power down adc */ + writel(0, &priv->regs->ctrl); + + priv->active_channel = -1; + + return 0; +} + +int rockchip_saradc_probe(struct udevice *dev) +{ + struct rockchip_saradc_priv *priv = dev_get_priv(dev); + struct clk clk; + int ret; + + ret = clk_get_by_index(dev, 0, &clk); + if (ret) + return ret; + + ret = clk_set_rate(&clk, priv->data->clk_rate); + if (IS_ERR_VALUE(ret)) + return ret; + + priv->active_channel = -1; + + return 0; +} + +int rockchip_saradc_ofdata_to_platdata(struct udevice *dev) +{ + struct adc_uclass_platdata *uc_pdata = dev_get_uclass_platdata(dev); + struct rockchip_saradc_priv *priv = dev_get_priv(dev); + struct rockchip_saradc_data *data; + + data = (struct rockchip_saradc_data *)dev_get_driver_data(dev); + priv->regs = (struct rockchip_saradc_regs *)dev_read_addr(dev); + if (priv->regs == (struct rockchip_saradc_regs *)FDT_ADDR_T_NONE) { + error("Dev: %s - can't get address!", dev->name); + return -ENODATA; + } + + priv->data = data; + uc_pdata->data_mask = (1 << priv->data->num_bits) - 1;; + uc_pdata->data_format = ADC_DATA_FORMAT_BIN; + uc_pdata->data_timeout_us = SARADC_TIMEOUT / 5; + uc_pdata->channel_mask = (1 << priv->data->num_channels) - 1; + + return 0; +} + +static const struct adc_ops rockchip_saradc_ops = { + .start_channel = rockchip_saradc_start_channel, + .channel_data = rockchip_saradc_channel_data, + .stop = rockchip_saradc_stop, +}; + +static const struct rockchip_saradc_data saradc_data = { + .num_bits = 10, + .num_channels = 3, + .clk_rate = 1000000, +}; + +static const struct rockchip_saradc_data rk3066_tsadc_data = { + .num_bits = 12, + .num_channels = 2, + .clk_rate = 50000, +}; + +static const struct rockchip_saradc_data rk3399_saradc_data = { + .num_bits = 10, + .num_channels = 6, + .clk_rate = 1000000, +}; + +static const struct udevice_id rockchip_saradc_ids[] = { + { .compatible = "rockchip,saradc", + .data = (ulong)&saradc_data }, + { .compatible = "rockchip,rk3066-tsadc", + .data = (ulong)&rk3066_tsadc_data }, + { .compatible = "rockchip,rk3399-saradc", + .data = (ulong)&rk3399_saradc_data }, + { } +}; + +U_BOOT_DRIVER(rockchip_saradc) = { + .name = "rockchip_saradc", + .id = UCLASS_ADC, + .of_match = rockchip_saradc_ids, + .ops = &rockchip_saradc_ops, + .probe = rockchip_saradc_probe, + .ofdata_to_platdata = rockchip_saradc_ofdata_to_platdata, + .priv_auto_alloc_size = sizeof(struct rockchip_saradc_priv), +};